The Annals of Thoracic Surgery, Vol 48, 829-834, Copyright © 1989 by The Society of Thoracic Surgeons
Effects of atrial cardioplegia on the ischemic right ventricle after acute coronary artery occlusion and reperfusion
JT Diehl, E Kaplan, AR Dresdale, A Kreis, MA Konstam, IM Ross, RJ Connolly, NG Pandian, M Aronovitz and DD Payne
Division of Cardiothoracic Surgery and Cardiology, New England Medical Center Hospitals, Boston, MA 02111.
Right atrial cardioplegia has been advocated as a simple method of
delivering retrograde cardioplegia. Passive distention of the right heart
inherent with right atrial cardioplegia has been shown to impair right
ventricular function in a canine model of global ischemia. This study was
designed to compare right ventricular performance after right atrial
cardioplegia administered intermittently (n = 5) and continuously (n = 5)
with coronary sinus retrograde cardioplegia (n = 5) and aortic root
cardioplegia (n = 8) in a canine model of acute right ventricular ischemia
and reperfusion. Right ventricular performance was assessed using the
load-independent relationship of end- systolic pressure versus dimension
(myocardial fiber length). Right ventricular performance was well preserved
after reperfusion in those dogs protected with intermittent right atrial
cardioplegia (95% of control). Results with continuous right atrial
cardioplegia (66% of control) and coronary sinus retrograde cardioplegia
(40% of control) demonstrated diminished postreperfusion right ventricular
performance. Right ventricular performance in the group protected with
aortic root cardioplegia was significantly impaired after reperfusion when
compared with all retrograde groups (34% of control, p less than 0.05). In
this model, postreperfusion right ventricular performance was preserved in
the right atrial cardioplegia groups despite passive ventricular
distention. All methods of retrograde cardioplegia resulted in superior
preservation of right ventricular performance when compared with standard
aortic root cardioplegia.