Glomerular filtration rate (GFR) is an important clinical indicator of kidney function. It can be used as an independent predictor of long-term survival after cardiac surgery. Definition, methods of measurement, and corrected value by body surface area are briefly introduced in this paper. Details of the calculation of estimated GFR (eGFR) by Levey's formula with serum creatinine, age, gender, and race are offered. The relationship between estimated GFR and the four factors is shown graphically and discussed. An eGFR/creatinine conversion table for individual patients derived from the eGFR equation with clinically significant cutpoints is given, which can be used by physicians as a pragmatic reference.
]]>Estimated glomerular filtration rate (eGFR) before coronary artery bypass graft (CABG) surgery is a key risk factor of in-hospital mortality. However, in patients with normal renal function before CABG, acute kidney injury develops after the procedure, making postoperative renal function assessment necessary for evaluation. Postoperative eGFR and its association with long-term survival have not been well studied.
We studied 13,593 consecutive CABG patients in northern New England from 2001 to 2006. Patients with preoperative dialysis were excluded. Data were linked to the Social Security Association Death Master File to assess long-term survival. Kaplan-Meier and log-rank techniques were used. Patients were stratified by established categories of postoperative eGFR (90 or greater, 60 to 89, 30 to 59, 15 to 29, and less than 15 mL · min–1 · 1.73 m–2).
Median follow-up was 2.8 years (mean, 2.7; range, 0 to 5.5). Patients with moderate to severe acute kidney injury (less than 60) after CABG had significantly worse survival than patients with little or no acute kidney injury (90 or greater).
Patients having moderate to severe acute kidney injury after CABG surgery had worse 5-year survival compared with patients who had normal or near-normal renal function.
Studies on the safety of aprotinin in coronary artery surgery have given conflicting results. Therefore, we studied the possible link between perioperative aprotinin treatment and renal dysfunction in patients undergoing first-time coronary surgery with a high risk of bleeding.
We performed a matched cohort study, comparing 200 patients receiving high-dose aprotinin with 200 patients receiving tranexamic acid during primary isolated coronary surgery. Patients were matched according to age, sex, and presence of acute coronary syndrome. Primary outcome was fractional change in creatinine clearance. Secondary outcomes were other evaluations of postoperative renal function, mortality, stroke, reoperation for bleeding, and transfusion requirements.
The groups were similar in baseline characteristics except that triple-vessel disease and history of myocardial infarction were more prevalent in the aprotinin group. No significant differences were found in fractional change in creatinine clearance (-11% versus –12%, medians, p = 0.75) or any other assessments of postoperative renal function between the tranexamic acid and the aprotinin group. Adverse event rates were similar: early mortality (3.5% versus 4.5%, p = 0.80), stroke (1.5% versus 2%, p = 1.0), reoperation for bleeding (3.5% versus 2.5%, p = 0.77), and 5-year survival (87% versus 84%, p = 0.17). Patients in the aprotinin group received fewer transfusions (48% versus 60.5%, p = 0.02), fewer units of packed red blood cells (2.0 versus 1.4, p = 0.02) and plasma (1.3 versus 0.5, p < 0.001), but more units of platelets (0.1 versus 0.2, p = 0.02).
Aprotinin treatment during primary coronary surgery was not associated with impaired postoperative renal function in comparison with patients treated with tranexamic acid.
Cardiac surgery with cardiopulmonary bypass (CPB) induces an acute phase reaction that is implicated in the pathogenesis of several postoperative complications. Studies have shown that proinflammatory cytokines are increased by acute hyperglycemia. Recent evidence suggests that insulin has antiinflammatory properties. Therefore, we hypothesized that high-dose insulin therapy would attenuate the systemic inflammatory response to cardiopulmonary bypass and surgery in coronary artery bypass patients while maintaining normoglycemia.
A total of 52 patients who presented for elective coronary artery bypass were randomized to receive intraoperative intravenous insulin infusion, titrated to maintain blood glucose concentrations less than 180 mg/dL (group I, n = 25), or receive intraoperative fixed high dose of intravenous insulin infusion (5 mU/kg/min) with dextrose 20% infused separately to maintain a blood glucose level between 70 and 110 mg/dL (group II, n = 27). Blood samples were collected at different time points to determine tumor necrosis factor (TNF), interleukin 6 and 8 (IL6 and IL8), and complement factor 3 and 4 (C3 and C4).
Patients in both groups had similar preoperative characteristics. Patients in the high-dose insulin group had higher blood insulin concentrations and tighter blood glucose control. There were lower levels of IL6 (150 pg/dL vs 245 pg/dL, p = 0.03), IL-8 (49 pg/dL vs 74 pg/dL, p = 0.05), and TNF (2.2 pg/dL vs 3.0 pg/dL, p = 0.04) in group II in the early postoperative period.
High-dose insulin therapy blunts the early postoperative surge in inflammatory response to CPB as reflected by decreased levels of IL6, IL8, and TNF.
The ideal revascularization strategy (bypass surgery versus percutaneous coronary intervention [PCI]) for patients with cardiogenic shock in the setting of left main coronary artery disease is unknown.
The Should We Emergently Revascularize Occluded Coronaries for Cardiogenic Shock Trial and Registry included 164 patients with left main disease who underwent revascularization. Although the standard of care at the time and the trial protocol recommended coronary artery bypass graft surgery for patients with left main disease, the revascularization strategy (79 coronary artery bypass graft surgery and 85 PCI) was individualized for each patient by site investigators.
The median time from myocardial infarction to revascularization was 24.3 hours (interquartile range, 8.7 to 82.5 hours) in the surgical group and 7.4 hours (interquartile range, 3.7 to 19.5 hours) in the PCI group (p < 0.05). Overall 30-day survival with surgery in this setting was 54% (95% confidence interval, 0.43 to 0.69) and was significantly superior to the 14% (95% confidence interval, 0.09 to 0.35) in the PCI group (p ≤ 0.001). When the left main was the infarct-related artery, the 30-day survival rate was 40% in the surgical group (n = 6) and 16% in the PCI group (n = 15; p = 0.03). Coronary artery bypass graft surgery (hazard ratio, 0.41; 95% confidence interval, 0.22 to 0.77; p = 0.006) and age (per 10 years, hazard ratio, 1.04; 95% confidence interval, 1.01 to 1.08; p = 0.02) were independently associated with 30-day survival.
Coronary artery bypass graft surgery appeared to provide a survival advantage over PCI at 30-day follow-up in patients with left main coronary artery disease. The impact of current PCI strategies on this subgroup is undetermined.
We seek to demonstrate the rationale and efficacy of a minimally invasive surgical approach to the treatment of atrial fibrillation (AF) that combines pulmonary vein antral isolation with targeted partial autonomic denervation.
The literature supporting the rationale of this approach is reviewed. Seventy-four patients underwent video-assisted bilateral pulmonary vein antral isolation with confirmation of block and partial autonomic denervation with follow-up of 6 months or greater and have a long-term rhythm monitor at 6 months.
Success was defined as no episodes greater than 15 seconds of AF on long-term monitoring. Treatment was successful in 83.7% of patients with paroxysmal AF and 56.5% of patients with persistent/long-standing persistent AF.
There are evidence-based data that support both pulmonary vein electrical isolation and targeted partial autonomic denervation in the treatment of AF. These techniques can be combined in a minimally invasive surgical approach. Early data suggest this is a safe and efficacious approach for the treatment of paroxysmal AF. Techniques are being developed for the minimally invasive surgical treatment of persistent AF from an epicardial approach.
Tricuspid regurgitation (TR) is common in patients undergoing mitral valve surgery, and atrial fibrillation (AF) can cause progression of TR. This study examined the hypothesis that correction of AF with the Maze procedure can prevent the late progression of TR after mitral valve surgery.
We compared severity of TR in 33 patients (January 1, 1993, to January 1, 2003) who underwent concomitant Maze procedure plus mitral valve surgery and converted to normal sinus rhythm postoperatively with case-matched control patients who underwent mitral valve surgery alone and remained in AF postoperative. Matched variables were age, sex, diabetes mellitus, left ventricular ejection fraction, and hypertension. Preoperative TR grade was similar between groups (Maze 2.2 ± 0.8 versus no-Maze 2.3 ± 0.8, p = 0.67). Patients with permanent transvenous pacemakers, organic tricuspid valve disease, and prior tricuspid valve surgery were excluded from this comparison.
Before hospital dismissal, average TR grade improved to 1.9 ± 0.9 in both groups; TR improved in 42% of patients in the Maze group and 36% of patients with preoperative AF and no Maze. At last follow-up, average TR grade remained stable at 1.9 ± 0.9 in the Maze group (p = 0.078 versus preoperative) with TR progression in only 9% of patients (3 of 33). In contrast, TR grade worsened to 2.7 ± 0.9 in the no-Maze group (p = 0.04 versus preoperative, p < 0.001 versus postoperative, p < 0.001 versus groups), and TR worsened in 45% of patients (15 of 33). In a multivariable model, performance of a Maze procedure was protective against the progression of TR.
Continued AF after mitral valve surgery can predispose a patient to progression of TR, and this progression is prevented in patients having successful concomitant Maze procedure.
Recent US and European registries have indicated 30% to 60% of patients with critical valvular aortic stenosis (AS) are not treated surgically, usually due to advanced age and comorbidities. We report on a Food and Drug Administration approved feasibility study of a less invasive transcatheter approach to potentially treat these high-risk patients.
Between December 2006 and February 18, 2008, 40 patients underwent transcatheter insertion of a balloon expandable stainless-steel stent with an internally mounted three-leaflet equine pericardial valve (Edwards Sapien Transcatheter Heart Valve; Edwards Lifesciences, Irvine, CA) into the aortic annulus using a transapical left ventricular insertion (TA-AVI). Patients were inoperable by conventional surgery, or extremely high risk based on Society of Thoracic Surgeons score greater than 15% or other documented risk factors.
All 40 valves were successfully delivered and 35 were successfully seated. Two valves embolized and required open aortic valve replacement (AVR), and one case of severe regurgitation later required AVR. In a further two patients placed on cardiopulmonary support, one valve later embolized and one migrated. There were 7 (17.5%) deaths within 30 days, and a further 2 (5%) deaths before discharge at 42 and 72 days. There were no immediate postoperative strokes after successful deployment. Valve area improved from 0.62 cm2 (SD of 0.13) to 1.61 cm2 (SD 0.37) at 30 days (p = <0.0001), with mean perivalvular regurgitation of 1.19 (SD 0.80). Mean follow-up was 143 days (SD 166 days) with 6 further deaths from comorbid disease, none valve or cardiac related. The Kaplan-Meier survival was 81.8% ± 6.2% at 1 month and 71.7% ± 7.7% at 3 months.
Transapical insertion of a balloon expandable stented valve is feasible but carries considerable risk and will be further evaluated in the PARTNER (Placement of AoRTic traNscathetER valve) randomized trial.
Concomitant mitral regurgitation (MR) is frequently seen in patients undergoing aortic valve replacement (AVR) for aortic stenosis. This study was undertaken to characterize the magnitude of MR in these patients and identify factors associated with significant postoperative change.
Between 2002 and 2006, 391 patients with stenotic AV disease but no structural mitral valve disease underwent AVR without coronary artery bypass grafting. Excluded were 164 patients with combined aortic and mitral intervention, right heart surgery, or moderate to severe aortic insufficiency, to yield a final study group of 227 patients. Follow-up echographic evaluation of MR was obtained in 87 of 219 patients (40%) discharged alive without mitral valve intervention.
Overall mortality was 3.5%. After AVR, intraoperative MR severity improved in 66% of patients. Independent predictors of lower postoperative MR were small left atrial size (p = 0.03), the presence of aortic insufficiency (p < 0.01), and preoperative congestive heart failure (p = 0.04). Prosthetic valve type or size was not an independent predictor of postoperative MR. After adjustment for intraoperative underestimation of MR grade, there was no difference between the postprocedural MR grade and the early or late follow-up MR grade (p = 0.6 and p = 0.8, respectively).
The results of this study support a conservative, tailored approach to concomitant mitral surgery in patients presenting for correction of aortic stenosis who demonstrate functional mitral regurgitation. Characteristics associated with resolution may allow for identification of patients most likely to benefit from mitral valve repair or replacement.
The purpose of this study was to evaluate outcome in patients with a small aortic root receiving either a standard CarboMedics mechanical aortic valve or a Top Hat CarboMedics valve (CarboMedics, Austin, TX), specifically designed for the small aortic root.
Between 1986 and 2006, 316 consecutive patients underwent 19- or 21-mm mechanical aortic valve replacement, receiving either a CarboMedics Top Hat bileaflet valve (n = 56; mean age, 66 ± 14 years) or a standard CarboMedics aortic valve replacement (n = 260; mean age, 60 ± 13 years) at our institution based on institutional indications for the choice of type of valve prostheses. Median follow-up time was 83.5 months. We studied survival, valve-related and non–valve-related events, and hemodynamic performance by serial echocardiographic follow-up studies.
In-hospital mortality was 8.9% in the Top Hat group and 10.0% in the standard group (p = 0.354). Five- and ten-year survival in patients in the Top Hat group was 83% and 67%, respectively. Five- and ten-year survival in the standard group was 73% and 59%, respectively (log-rank = 0.331). There were no differences in regard to valve-related and non–valve-related events. Cox regression analysis revealed age (hazard ratio, 1.045; 95% confidence interval, 1.026 to 1.066), previous cardiac surgery (hazard ratio, 1.812; 95% confidence interval, 1.101 to 2.982), additional procedures at the time of valve replacement (hazard ratio, 2.604; 95% confidence interval, 1.651 to 4.108), New York Heart Association class IV (hazard ratio, 3.645; 95% confidence interval, 1.214 to 10.945), and severely impaired left ventricular ejection fraction (hazard ratio, 2.253; 95% confidence interval, 1.289 to 3.941) to be independent predictors of survival.
Mechanical aortic valve replacement in the small aortic root is associated with substantial perioperative mortality, in particular in the subset of patients requiring additional cardiac surgical procedures. Nevertheless, long-term outcome is satisfying. Because the type of prosthesis does not predict outcome in the multivariate Cox model, we conclude that use of the smaller Top Hat prosthesis can be recommended for the challenging cohort of patients with a small aortic root.
Calcific aortic stenosis may be an inflammatory disease with active bone formation in the valve leaflets rather than a disease of passive calcium deposition. Epidemiologic data demonstrating correlation of poor dental hygiene to atherosclerotic pathologies suggests that circulating bacterial products could be involved in the pathogenesis of aortic valve stenosis. We hypothesized that lipopolysaccharide (LPS) stimulation of human aortic valve interstitial cells (HAVICs) would induce inflammatory and osteogenic gene expression.
The HAVICs were isolated from normal aortic valves obtained from explanted hearts during transplantation (n = 5) and grown in culture. Cells underwent 4 and 24 hours of LPS stimulation (LPS, 200 ng/mL) or β-glycerol phosphate treatment (BGP) (osteogenic media as positive control). Media was removed for interleukin (IL)-6 and IL-8 immunoassay. Ribonucleic acid was extracted for microarray analysis. Statistics were by analysis of variance with post-hoc analysis (p < 0.05).
The LPS stimulation induced the gene expression of proinflammatory cytokines, chemokines, and adhesion molecules. Protein level confirmation by immunoassay demonstrated 3.4-fold (± 0.35, p < 0.01) and 9.5-fold (± 1.5 p < 0.01) increase over control of IL-6 and IL-8, respectively. The LPS and BGP both induced critical mediators of osteogenesis including bone morphogenetic protein 2 and platelet-derived growth factor alpha.
The LPS stimulation of HAVICs not only induces inflammatory mediators but also induces gene expression of osteogenic factors, similar to that induced by osteogenic media. Bacterial products stimulation, likely by toll-like receptor 4 and the innate immune system, may contribute to the pathogenesis of aortic valve stenosis.
Mitral valve replacement is more frequently performed and perceived to be equivalent to repair in elderly patients, despite the superiority of repair in younger patients. Our objective was to compare mitral repair to replacement in elderly patients age 75 years or older. Patients younger than 75 years undergoing mitral valve surgery served as a reference population.
Consecutive elderly patients undergoing operation for mitral regurgitation at our institution from 1998 to 2006 were reviewed. Elderly patients (mean age, 78.0 ± 2.8 years) who underwent mitral repair (n = 70) or replacement (n = 47) were compared with cohorts of young patients (mean age, 58.9 ± 9.3 years) who underwent repair (n = 100) or replacement (n = 98) during the same period. Patient details and outcomes were compared using univariate, multivariate, and Kaplan–Meier analyses.
Mitral replacement in elderly patients had higher mortality than repair (23.4%, 11 of 47 versus 7.1%, 5 of 70; p = 0.01) or as compared with either operation in the reference group (p < 0.0001). Postoperative stroke was higher in elderly replacement patients compared with repair (12.8%, 6 of 47 versus 0%; p = 0.003) or compared with either young cohort (p = 0.02). Compared with elderly repair patients, elderly replacement patients had more cerebrovascular disease (21.3%, 10 of 47 versus 4.3%, 3 of 70; p = 0.005) and rheumatic mitral valves (21.3%, 10 of 47 versus 0%; p = 0.0001). In the young group, overall complication and mortality were no different between replacement and repair. Long-term survival favored repair over replacement in elderly patients (p = 0.04). One elderly repair patient experienced late recurrence of persistent mitral regurgitation.
In patients age 75 years or older, mitral repair is associated with a lower risk of mortality, postoperative stroke, and prolonged intensive care unit and hospital stay compared with mitral replacement. Mitral repair can be performed in preference over replacement even in patients older than the age of 75.
Conventional open repair of acute complicated type B aortic dissection is associated with significant morbidity and mortality. This study examined the results of thoracic endovascular aortic repair (TEVAR) in acute type B aortic dissection complicated with rupture or malperfusion syndrome.
From 2004 through 2007, 35 patients (22 men) with acute complicated type B aortic dissection were treated with TEVAR. Indications included rupture in 18 (51.4%) and malperfusion syndrome in 17 (48.6%; mesenteric or renal, 5;lower extremities, 3; both, 9). Three types of endograft devices were used (mean per patient, 1.9 devices). Intravascular ultrasound imaging was used in 15 patients (42.8%). In patients with malperfusion syndrome, distal adjunct procedures to expand the true lumen included infrarenal aortic stents in 4, mesenteric/renal stents in 4, and iliofemoral stents in 7. Follow-up was 93.9% during a period of 18.3 months (range, 3 to 47 months).
The mean age was 58.6 ± 13.4 years. Technical success (coverage of the primary tear site) was achieved in 34 patients (97.1%). Coverage of the left subclavian artery was required in 25 patients (71.4%). Thirty-day mortality was 2.8%. One-year survival was 93.4% ± 4.6%. Complications included permanent renal failure (2.8%), stroke (2.8%), spinal cord ischemia (transient [5.7%], permanent [(2.8%]), and vascular access (14.2%). The mean intensive care unit and hospital stay were 4.7 ± 2.6 and 16.7 ± 12.0 days, respectively.
Endovascular repair of acute complicated type B aortic dissection is associated with low morbidity and mortality and has emerged as the surgical therapy of choice.
To possibly prevent late complications after classic type A aortic dissection repair, the radical concept of ascending/arch replacement with simultaneous antegrade descending stent grafting using a hybrid prosthesis was applied and compared with conventional repair leaving the distal false lumen untreated.
Between January 2001 and October 2007, of 71 consecutive patients with acute type A aortic dissection (AAAD), 45 had DeBakey type I dissection and underwent emergency surgery within 24 hours after onset of symptoms. These patients were separated into group 1 (n = 23) undergoing conventional surgery, and group 2 (n = 22) undergoing combined repair with antegrade stent grafting.
Patients were comparable for baseline characteristics, but more group 2 patients had severely compromised hemodynamics (p = 0.05) and cerebral malperfusion at arrival (p < 0.01). Intraoperative and postoperative characteristics were similar, with an overall hospital mortality of 16% (5 [22%] versus 2 [9%], group 1 versus group 2; p = 0.22). At a mean follow-up time of 48 months for group 1 versus 23 months for group 2 (p < 0.01), late mortality did not differ between groups (p = 0.38) and was mainly related to additional surgical procedures and persisting neurologic sequelae and not to the aortic pathology. Persisting distal false lumen patency was observed in 89% of group 1 versus 10% of group 2 patients (p < 0.01).
This hybrid approach to patients with type I acute aortic dissection is technically feasible without increasing the operative risk and offers the chance of persistent occlusion of the persistent graft distal false lumen.
Surgery for acute type B aortic dissection is associated with significant mortality and morbidity. The purpose of this study was to assess the clinical outcome of surgical management of complicated acute type B aortic dissection.
During the last 5 years, 112 patients were admitted for acute type B aortic dissection. Of these patients, 24 consecutive patients were enrolled who underwent surgical management during the acute or subacute stage. The mean age was 66.7 ± 9.1 years; 8 patients were female. Indications for surgery were rupture in 10 patients, impending rupture in 7, and malperfusion in 7. Fifteen patients were transferred from another hospital. The overall clinical outcome including morbidity, aorta-related events, and death were retrospectively assessed.
The mean duration from the time of onset to surgery was 7.1 ± 9.0 days. Graft replacement of the aorta included the total aortic arch with cerebral perfusion in 6 patients, and replacement of the distal aortic arch or descending aorta with left heart bypass in 12. The remaining 6 patients underwent peripheral bypass for ischemia. Significant complications occurred in 7 patients (24.8%). The operative mortality rate was 8.3% (2 of 24); 5.6% (1 of 18) with central operation and 16.7% (1 of 6) with peripheral operation. The 5-year survival rate was 82.6 ± 7.9% and freedom from aorta-related events at 1 and 5 years were 95.2% ± 4.7% and 68.0% ± 16.6%, respectively.
Surgical management of patients with complicated acute type B dissection has an acceptable perioperative risk and survival. This study suggests earlier surgery with left heart bypass may be beneficial for appropriate patients.
Idiopathic dilated cardiomyopathy (DCM) is characterized by ventricular wall remodeling and an increased frequency of cardiac cell apoptosis. Apollon is a 528kD cell membrane-anchored protein that inhibits apoptosis by ubiquitinylation facilitating the degradation of Smac/Diablo and caspase-9. The present study tested the hypothesis that the Apollon/Smac system may mediate programmed cell death in DCM.
Apollon and caspase-9 protein expression was assessed in left ventricular biopsies of explanted failing hearts using Western blotting in 36 DCM patients undergoing cardiac transplantation and in 10 controls. Human cardiac cells were transfected with a plasmid containing the human Apollon complementary DNA or control vector and were subsequently stressed by hypoxia. Apollon, Smac/Diablo, and caspase-9 expression were then examined in cell lysates by real-time polymerase chain reaction and a transferase-mediated dUTP nick-end labeling assay was used to determine the apoptotic index.
In DCM myocardial tissue, Apollon messenger (m)RNA and protein expression was down-regulated compared with control hearts (p < 0.001 and p < 0.005, respectively) concomitant with an increase in activated caspase-9 protein levels (p < 0.001). Cell stress resulted in increased apoptosis in cardiac cells in vitro and down-regulation of Apollon mRNA expression compared with control cells (p < 0.001). Transfection increased Apollon mRNA expression in cell lysates (p < 0.001) and completely prevented hypoxia-induced apoptosis associated with reduced expression of Smac/Diablo and activated caspase-9.
These results suggest that Apollon down-regulation plays a role in programmed cell death associated with DCM. Up-regulation of Apollon might therefore represent a novel therapeutic strategy in the treatment of DCM.
Pulmonary dysfunction presumably linked to an inflammatory response is frequent after cardiac operations using cardiopulmonary bypass (CPB) and pulmonary hypoperfusion. We previously demonstrated that active perfusion of the lungs during CPB reduces ischemic lung injury. We now hypothesized that avoiding ischemia of the lungs during CPB by active pulmonary perfusion would decrease pulmonary inflammatory response.
Pigs were randomized to a control group with CPB for 120 minutes, followed by 120 minutes of postbypass reperfusion, or to the study groups where animals underwent active pulmonary perfusion with pulsatile or nonpulsatile perfusion during CPB (n = 7 in each group). Activation of transcription factor activity (nuclear factor [NF]-B and activating protein [AP]-1) was determined by electrophoretic mobility shift assay. Levels of proinflammatory protein expression (interleukin [IL]-1, IL-6, and tumor necrosis factor [TNF]-) were quantified by enzyme-linked immunoabsorbent assay. Caspase-3 activity was measured using a fluorogenic assay.
The activation of transcription factor AP-1 and NF-B was reduced in the pulsatile pulmonary perfusion group. The caspase-3 activity and the expression of IL-1, IL-6, and TNF- revealed a significant decrease in the pulsatile and nonpulsatile pulmonary perfusion groups. Animals of the pulsatile pulmonary perfusion group showed significantly reduced IL-6 expression and caspase-3 activity compared with the nonpulsatile pulmonary perfusion group.
Active pulmonary perfusion reduces the inflammatory response and apoptosis in the lungs observed during conventional CPB. This effect is greatest when pulmonary perfusion is performed with pulsatility. The reduction in cytokine expression by pulsatile pulmonary perfusion might be mediated by AP-1 and NF-B.
The study was designed to determine whether cardiac surgical outcomes are affected during times of major turnover of cardiothoracic resident surgical staff and at the beginning versus the end of their training periods.
This observational cohort study analyzed data from cardiac operations between April 1996 and March 2006 at a single institution. In-hospital mortality and other outcomes were compared between operations done during months of major change in resident staff rotation (July, August, January, February, n = 5,517) and the rest of the year (n = 10,773). We also compared outcomes at the beginning and end of surgical rotation for cardiothoracic residents. Adjustment was made for EuroSCORE (European System for Cardiac Operative Risk Evaluation), year of operation, and surgeon resident status. Analyses were done within surgery procedure subgroups of isolated coronary artery bypass graft surgery (CABG) and complex operations (CABG combined with other procedures).
Patient populations in the groups were similar. After risk adjustment, there was a significant increase in hospital mortality for the complex cases during months of resident staff change compared with rest of the year (odds ratio 1.3, 95% confidence interval: 1.3, 1.4; p = 0.02). There was, however, no significant difference in mortality for the CABG only cases (odds ratio 1.1, 95% confidence interval: 0.8, 1.4; p = 0.61). Risk-adjusted mortality after operations done by residents was the same at the start and finish of their surgical rotation. During the change months, the surgery time was 2.2 minutes longer on average in CABG operations (95% confidence interval: 0.3, 4.0; p = 0.02), and no different in combined cases.
Periods of major change in resident surgical staff are associated with increased risk-adjusted in-hospital mortality after complex cardiac operations but not after CABG alone.
Reconstruction of the right ventricular outflow tract is a frequently encountered component of many congenital cardiac repairs. We sought to tissue engineer pulmonary artery augmentation patches from retrovirally labeled endothelial progenitor and mesenchymal stem cells and determine the persistence of the seeded cells in vivo.
Autologous ovine endothelial progenitor and mesenchymal stem cells were labeled with a retroviral vector encoding green and red fluorescent proteins, coseeded onto biopolymers, and cultured for 5 days. The tissue-engineered patches were implanted into the main pulmonary artery with 1, 2, 4, and 6 week in vivo maturation (n = 8). In vivo evaluation included ultrasonography and angiography, with preimplant and explanted specimens evaluated using histologic examination and immunofluorescence.
Echocardiography at each time demonstrated laminar pulmonary artery flow without a pressure gradient across the replaced segment. Pulmonary angiography did not exhibit stenosis or aneurysmal change. Gross appearance of all explanted patches showed progressive tissue formation with increased length of time in vivo. Retrovirally labeled cellular persistence was 96%, 82%, 85%, and 66% at 1, 2, 4, and 6 weeks after implantation, respectively. Early in the in vivo remodeling period, the number of green fluorescent protein–positive endothelial progenitor cells was 1.6 fold greater than the red fluorescent protein–positive mesenchymal stem cells. As in vivo remodeling continued, red fluorescent protein–expressing mesenchymal stem cells were expressed 1.2 to 1.7 times that of the green fluorescent protein–positive endothelial progenitor cells.
The data demonstrate the successful creation of an anatomically functional, autologous tissue-engineered pulmonary artery using coseeded progenitor cell sources. Labeled implanted stem cells persisted in the engineered construct, suggesting that in vitro seeding is necessary to engineer tissue. This study demonstrates an effective method to track multiple cell types after implantation.
Both surgical repair and transcatheter closure of isolated ventricular septal defects are known to have limitations in children. This report describes the short-term results of perventricular device closure of nonmuscular ventricular septal defects without cardiopulmonary bypass in young children.
Thirty patients who had nonmuscular ventricular septal defects underwent perventricular closure by minimally invasive technique without cardiopulmonary bypass. A subxiphoid minimally invasive incision was performed. Under the continuous guidance of transesophageal echocardiography, the free wall of the right ventricle was punctured and a guidewire was introduced into the left ventricle through the defect. A delivery sheath was advanced over the wire and through the defect into the left ventricle. The device was released.
Closure was successful in 27 patients (90%). There was no mortality or atrioventricular block perioperatively or during the entire follow-up period. Three patients developed incomplete right bundle branch blocks and seven patients developed new trace or mild tricuspid regurgitation after the closure. The mean hospital stay was 3.6 ± 0.7 days (range, 3 to 5 days) and no patient needed any blood or blood products. Follow-up at 6 months showed that two of the three patients had persistent incomplete right bundle branch block and three of the seven patients had persistent closure-related trace or mild tricuspid regurgitation.
Perventricular device closure of isolated ventricular septal defects without cardiopulmonary bypass appeared to be safe and efficacious in selected young children. The outcomes of short-term follow-up are acceptable.
Left atrioventricular valve regurgitation (LAVVR) is a major cause of morbidity after atrioventricular septal defect (AVSD) repair. This study evaluates the outcomes of repair and replacement of the left atrioventricular valve after AVSD correction, as well as factors predictive of durability of valve repair.
Between January 1983 and March 2007, 31 patients underwent reoperation for LAVVR after AVSD repair (23 valve repairs and 8 valve replacements). Median age at primary repair was 5.0 months and time to reoperation was 5.0 months. The distribution of AVSD morphology was 9 primum, 5 transitional, and 17 complete.
Early postoperative mortality was 6.4% (2 of 31). Survival at 10 years was 88.1%. At a mean follow-up of 8.2 years, 86% of hospital survivors were in New York Heart Association class I. Overall freedom from reintervention at 10 years was 67.2%. Among patients undergoing primary repair, 6 of 23 underwent subsequent replacement. Follow-up LAVVR in those who did not require subsequent valve replacement was mild or less in 92.8%. Factors that demonstrated a trend toward durable repair included the use of patch augmentation rather than primary cleft closure (p = 0.02) and earlier timing to repair (less than 2 months; p = 0.03). Significant cardiomyopathy developed in 21.4% of patients after prosthetic valve replacement (3 of 14).
Surgical management of LAVVR after AVSD repair can be performed with excellent midterm outcomes. However, both repair and replacement are associated with a high incidence of reoperation. Nonetheless, an aggressive reparative approach should be pursued to avoid the morbidity of pediatric left atrioventricular valve replacement that includes anticoagulation, inevitable reoperation, and cardiomyopathy.
Records of patients who had repair of sinus venosus defect (SVD) between 1970 and 2008 were reviewed to predict very long-term outcome.
Repairs occurred in 104 consecutive patients (51 men), aged 29 ± 23 years (range, 1 to 70 years). Seven had isolated SVD and 97 had associated lesions that required concomitant operations. Five patients had preoperative arrhythmias; 24 (23%) were in New York Heart Association (NYHA) class III to V. Single-patch repair was done in 91 patients, caval translocation (Warden) in 7, and double-patch in 6.
Ten late deaths during 38 years of follow-up (mean, 15 ± 20 years). Survival was 97% ± 2% and 79% ± 7% at 10 and 30 years. Thirty-one (29%) long-term survivors experienced 47 complications, including chronic/recurrent supraventricular tachycardia in 28, heart failure in 5, permanent pacing in 8, cerebrovascular accident in 3, and unrelated cardiac reoperation in 3. At 30 years, freedom from adverse cardiac events was 47% ± 9%, from supraventricular tachycardia, 50% ± 9%; from permanent pacing, 83 ± 6%; and from cerebrovascular accident, 96% ± 2%. Follow-up age was 42 ± 23 years (range, 5 to 82 years); 74 patients (79%) were in NYHA class I, and 15 and 5 were in class II and III to IV, respectively. Baseline cardiac rhythm was sinus in 75 patients (84%), atrial fibrillation in 11 (12%), and paced in 8. Nine patients had moderate/severe pulmonary hypertension, and 8 had left ventricular dysfunction. Only older age at operation was associated with lower survival (p = 0.003), freedom from cardiac events (p = 0.001), supraventricular tachycardia (p = 0.009), and permanent pacing (p = 0.002). Repair before age 20 was associated with lower NYHA class at follow-up (p = 0.01).
SVD repair at an older age is associated with increased risk of late mortality, adverse cardiac events, and worse functional outcome. Repair during childhood is strongly advised.
Mitral valve repair for rheumatic mitral valve disease in children has become the preferred surgical modality. A mitral valve ring is frequently used in the repair. A recently introduced biodegradable ring has shown promising results and allows for growth of the native annulus.
Between January 1994 and March 2006, 220 children underwent mitral valve repair for rheumatic valve disease. Mitral valve insufficiency was predominant in 198 patients (90%). Fifty-seven patients (26%) had associated aortic valve insufficiency and 51 (23%) had tricuspid valve insufficiency addressed during the same surgery. A mitral valve ring was used in 213 patients (173 Carpentier-Edwards and 40 biodegradable rings). Ninety-two percent (202 of 220) were in New York Association class III to IV. Echocardiography was performed at 6 months and thereafter once yearly.
There were no hospital deaths or major postoperative morbidity. Follow-up was complete in 96% (212 of 220). One late death occurred. Mean follow-up was 76.4 months (range, 1 to 13 years). One patient (0.5%) had immediate mitral valve repair failure and required mitral valve replacement. Twelve patients (5.5%) required reoperation during follow-up. Recurrent mitral valve insufficiency/stenosis-free survival was 94.5% at 5 years and 92.7% at 10 years. Mean gradient was 5.2 ± 1.9, 6.2 ± 2.0, and 7.0 ± 2.3 mm Hg, respectively, at 7 days, 6 months, and 1 year postoperatively for the Carpentier-Edwards ring and significantly lower (p < 0.001) for the biodegradable ring at 2.8 ± 0.5, 3.1 ± 0.7, and 3.3 ± 0.5 mm Hg, respectively. Unchanged mean gradient during the first year was 65% (26 of 40) for the biodegradable ring and 21% (31 of 147) for the Carpentier-Edwards ring.
Mitral valve repair in children with rheumatic valve disease has excellent immediate results with low operative risk and satisfactory midterm results and should therefore be the preferred treatment of choice. The use of biodegradable mitral valve ring results in a significant lower mean gradient during the first year of implantation compared with the Carpentier-Edwards ring and is available in a wide range of sizes.
Optimal repair of anomalous origin of left coronary artery from pulmonary artery (ALCAPA) relies on the creation of a dual-coronary system. If the anomalous coronary arises at a long distance from the aorta, we use various coronary extension techniques to facilitate tension-free implantation.
Thirty patients underwent ALCAPA operations using direct coronary transfer (n = 11) or coronary extension techniques (n = 19). Surgical outcomes were analyzed.
Median age and weight were 5.7 months (range, 46 days to 5.45 years) and 5.35 kg (range, 3.3 to 15.9 kg). Five patients had concomitant mitral annuloplasty. Mean cardiopulmonary bypass and ischemic times were 108 ± 38 and 57 ± 25 minutes. Two patients required intraoperative revision of the implantation. There were three hospital deaths (10%) and no late deaths. Follow-up echocardiograms demonstrated significant improvement postoperatively vs preoperatively in shortening fraction (35% ± 2% vs 16% ± 2%, p < 0.00001), ejection fraction (64% ± 3% vs 32% ± 4%, p < 0.00001), and mitral regurgitation (11% moderate vs 70% moderate or severe, p = 0.0002). Left ventricular end-diastolic dimension Z-score decreased from 9.1 ± 0.9 to 1.2 ± 0.5 (p < 0.00001). Both techniques were equally effective. Two patients underwent reoperation 1 and 12 years postoperatively (coronary artery bypass grafting, 1; mitral repair with coronary angioplasty, 1). Surviving patients remain asymptomatic (p < 0.00001).
Dual-coronary system can be established in patients with ALCAPA. Coronary extension implantation techniques have acceptable operative mortality and excellent cardiac recovery and late survival. Although the rate of late coronary occlusion is low, continual ventricular or mitral dysfunction should trigger evaluation of persistent coronary compromise.
Patients who underwent Fontan operation have some degree of liver disease. We aimed to assess the long-term liver and cardiac function after Fontan operation.
Patients enrolled underwent physical examination, biochemical tests (aspartate aminotransferase, alanine aminotransferase, gamma glutamyl transpeptidase, bilirubin, international normalized ratio, coagulation factor V, protein profile, fecal alpha-1-antitrypsin), echocardiogram, and liver ultrasonography. A liver disease score was adopted to compare the degree of liver involvement with hemodynamic features.
The study enrolled 34 patients, median age 14.7 years (range, 4.1 to 26.7), 26 with a residual left ventricle, 8 with a residual right ventricle, affected by tricuspid atresia (17), pulmonary atresia (4), hypoplastic left heart syndrome (5), double-outlet right ventricle (2), single left ventricle (2), and miscellaneous (4), with median follow-up of 11.5 years (range, 1.7 to 23.3). We found hepatomegaly in 18 of 34 (53%), splenomegaly in 3 of 33 (9%), abnormal transaminases in 10 of 33 (30%), elevated GT in 19 of 31 (61%), elevated bilirubin in 10 of 31 (32%), coagulopathy in 17 of 29 (58%), and protein-losing enteropathy in 4 of 21 (19%). Median heart rate z-score was –1.72. Hepatic dysfunction was strictly correlated to low cardiac index (r2 = 0.34, p = 0.008) and to a lesser extent to reduced heart rate (r2 = 0.18, p = 0.07).
In children who underwent Fontan operation, hepatic dysfunction is correlated with low cardiac index and reduced heart rate. Maintaining or reestablishing a normal cardiac index might prevent or reduce liver disease in the long-term.
Traditional palliation of infants with biventricular hearts and inadequate pulmonary blood flow is a modified Blalock-Taussig shunt. The aim of this report is to assess the results of an alternative, right ventricle-to-pulmonary artery (RV-PA) shunt.
Between August 2004 and July 2007, 10 infants with biventricular hearts and inadequate pulmonary blood flow underwent palliation with an RV-PA shunt. Median age was 9 days (range, 4 to 86), weight was 3.0 kg (1.7 to 4.5), and 4 of 10 patients weighed less than 2.5 kg. Shunts were nonvalved Gore-Tex (W.L. Gore Assoc, Flagstaff, AZ), and size was 6 mm (n = 5) or 5 mm (n = 5).
There were no operative deaths. Median oxygen saturation at hospital discharge was 95% (87 to 98). In 2 patients the shunt was partially narrowed with a metal clip; they underwent successful balloon dilation 6 months after shunt placement. Eight patients have undergone two-ventricle repair 6 to 17 months after shunt placement. At the time of complete repair, oxygen saturation was 86 ± 1% and weight was 7.7 ± 1.7 kg. Repairs included a valved RV-to-PA conduit, 14 to 16 mm in diameter. There was one interstage death.
The RV-PA shunt provides successful palliation in infants with biventricular heart disease and inadequate pulmonary blood flow. It can be used in low birth weight infants and allows significant growth with protection of oxygen saturation prior to complete repair. Partial clipping of the shunt with subsequent balloon dilation is an option to prolong palliation. These results compare favorably with those of a modified Blalock-Taussig shunt or single stage complete repair.
Primary graft dysfunction (PGD) in the immediate post–lung transplant period strongly increases the risk of chronic rejection (broncholitis obliterans syndrome). Here, we hypothesized that PGD-induced inflammation augments alloimmunity, thereby predisposing to broncholitis obliterans syndrome.
Primary graft dysfunction and broncholitis obliterans syndrome were diagnosed according to the established International Society for Heart and Lung Transplantation criteria. Anti–human leukocyte antigen (HLA) alloantibodies were analyzed using Flow-PRA. Donor HLA class II–specific T cells were analyzed using interferon (IFN)- ELISPOT. Serum levels of 25 cytokines and chemokines were measured using LUMINEX.
Of the 127 subjects, 29 (22.8%) had no PGD (grade 0), 42 (33.2%) had PGD-1, 36 (28.3%) had PGD-2, and 20 (15.7%) had PGD-3. Patients with PGD grades 1 to 3 (PGD1-3) had elevated proinflammatory mediators MCP-1, IP-10, interleukin (IL)-1β, IL-2, IFN-, and IL-12 in the sera during the early posttransplant period compared with patients with PGD grade 0 (PGD0). On serial analysis, PGD1-3 patients revealed increased development of de novo anti-HLA-II (5 years: 52.2% versus PGD0 13.5%, p = 0.008). However, no difference was found in anti-HLA-I alloantibody development (PGD1-3 patients 48% versus PGD0 39.6%, p = 0.6). Furthermore, PGD1-3 patients had increased frequency of donor HLA class II–specific CD4+ T cells [(91.4 ± 19.37) x 10–6 versus (23.6 ± 15.93) x 10–6, p = 0.003].
Primary graft dysfunction induces proinflammatory cytokines that can upregulate donor HLA-II antigens on the allograft. Increased donor HLA-II expression along with PGD-induced allograft inflammation promotes the development of donor specific alloimmunity. This provides an important mechanistic link between early posttransplant lung allograft injury and reported association with broncholitis obliterans syndrome.
Although transbronchial biopsy (TBB) is the definitive method for diagnosing graft dysfunction after pediatric lung transplantation, concern over procedural complications has limited its use. We reviewed our institutional experience with clinically indicated TBB to determine its safety and efficacy with emphasis on how biopsy findings altered management.
A retrospective chart review was done of 61 pediatric lung transplantation patients undergoing 179 TBB procedures. Data were collected on pre-TBB symptoms, pulmonary function testing, and imaging studies. The prebiopsy diagnosis was noted and compared with the findings from TBB to see how frequently treatment changed after biopsy.
Age at TBB ranged from 2 months to 20 years, with an average of 3 biopsies per patient. There was no procedure-related mortality. The incidence of complications was 9% and included important bleeding with spontaneous resolution in 6% and pneumothorax in 3%. The usual indication for TBB was a change in the chest roentgenogram, frequently accompanied by a decrease in flows on spirometry. The TBB specimens were adequate for pathologic analysis 92% of the time, and a specific pathologic diagnosis could be made in 54% of cases. The findings from TBB altered the clinical management of the patient 64% of the time.
In pediatric lung transplant recipients presenting with graft dysfunction, TBB is a low-risk diagnostic procedure that yields clinically useful information in a majority of cases. In our experience, the findings from TBB altered medical treatment in 64% of patients. Treatment was most often changed in the group diagnosed with rejection as the probable cause of graft dysfunction.
For patients with end-stage emphysema undergoing lung volume reduction surgery (LVRS), we have preferred a bilateral (BLVRS) approach to achieve maximum benefit with a single procedure. A unilateral (ULVRS) approach has been used in certain patients in whom BLVRS is contraindicated.
Between January 1993 and December 2006, 43 consecutive patients underwent ULVRS. The study excluded patients undergoing giant bullectomy. Relative contraindications for BLVRS were unilateral emphysema, 21; unilateral emphysema plus other factors, 2; and other factors alone, 10. Preoperative pulmonary rehabilitation was required. Postrehabilitation data were used as the baseline for analyses. Outcome measurements for ULVRS were compared with BLVRS results.
After ULVRS, the mean increase in forced expiratory volume in 1 second (FEV1) from postrehabilitation values was 32% at 6 months (p ≤ 0.001) and 28% at 3 years (p = 0.036). The FEV1 was not significantly improved at 5 years. The mean reduction in residual volume after ULVRS was 23% at 6 months (p ≤ 0.001) and 38% at 5 years (p = 0.001). Supplemental oxygen requirements declined initially postoperatively. One patient (2%) died in the hospital. The 90-day mortality was 0%. Kaplan-Meier survival after ULVRS was 97.7%, 80.9%, and 45.5%, at 1, 3, and 5 years.
ULVRS produces improvements in pulmonary function, exercise capacity, and quality of life with an acceptable morbidity and mortality in patients for whom BLVRS is contraindicated, but the benefits are of lower magnitude than those achieved with BLVRS.
We aimed to develop and validate a scoring system to predict intensive care unit (ICU) admission for complications after major lung resection for purposes of optimizing planning of resources for patient care.
Patients undergoing major lung resections performed between 2000 and 2006 at three thoracic surgery units were analyzed for unplanned admission to the ICU for complications. Variables were initially screened by univariate analysis. Selected variables were used in a stepwise logistic regression analysis that was validated by bootstrap analysis. The scoring system was developed by proportional weighting of the significant and reliable predictors estimates and validated on patients operated on in a different center.
In the derivation set of 1297 patients, 82 (6.3%) had ICU admission for complications, and 30 died (associated mortality rate, 36.5%). Predictive variables and their scores were pneumonectomy, 2 points; and 1 point each for age older than 65, predicted postoperative forced expiratory volume in 1 second below 65%, predicted postoperative carbon monoxide lung diffusion capacity below 50%, and cardiac comorbidity. Patients were grouped into three risk classes by their scores, which were significantly associated with incremental risk of ICU admission in the validation set of 349 patients.
This scoring system predicts incremental risk of ICU admission for complications after major lung resection. This system may help in assessing the need for additional postoperative resources and in modifying indicators used to determine the appropriateness of initial transfer of postoperative patients from ICU or stepdown status and in developing criteria for future cost-effectiveness trials.