Selective cardiac hypothermia versus coronary perfusion. A study of ischemic complications in two series of 100 consecutive valvular patients.

Myocardial protection, in two parallel series of 100 consecutive valvular patients operated upon between June 1972 and July 1973 in Broussais Hospital, was afforded in two different ways: one withh hypothermic ischemia (H.I.) as it was advocated by N. Shumway, the other with coronary perfusion (C.P.) of a beating heart with consecutive ischemic periods limited to 20 minutes. Three parameters were used to evaluate the quality of protection: death with primary cardiogenic shock, post-operative myocardial infarction and acute cardiac insufficiency making it necessary to use post-operative inotropic support. Death was 1% (H.I.) and 5% (C.P.). Infarctions were 5% (H.I.) and 8% (C.P.). Acute cardiac insufficiency was: with cardiogenic shock 0% (H.I.) and 4% (C.P.), without cardiogenic shock 8% (H.I.) and 2% (C.P.). Peculiar aspects of myocardial infarction in each series are analyzed, and apparent absence of correlation between aortic cross-clamp time and ischemic complications is discussed. A "myocardial intrinsic factor" seems to be part of each valvular group and appears also to be an important factor in producing ischemic complications.