Myocardial Protection During Open-Heart Surgery: Coronary Perfusion Versus Topical Cardiac Hypothermia

An experimental evaluation of continuous normothermic, intermittent hypothermic, and intermittent normothermic coronary perfusion

“…MYOCARDIAL COOLING For many surgeons, myocardial cooling is a complete substitute for perfusion; the duration of its protection depends on its degree (Angell et al, 1969). It has been used with success for seven hours (Lower et al, 1962) and, by some, is preferred to perfusion (Robicsek et al, 1970). Used with ether anaesthesia (Barnes, Mohri, and Merendino, 1968) or slow pacing (Mohri, 1965), fibrillation may be avoided, though this is not damaging over short periods (Martino et al, 1969).…”

“…Moreover, the provision of coronary perfusion does not prevent ischaemic enzyme changes during aortic valve surgery (Littler et al, 1972). The dangers of coronary perfusion may thus outweigh its benefits (Robicsek et al, 1970). HYPOTHERMIA Even perfusion of the heart from the aorta may be overdone, with resulting myocardial damage, when the cooling of the heart or the presence of ventricular fibrillation disturbs the autoregulation of coronary flow (Vasko, 1967).…”

Preoperative Topical Hypothermia used in Prolonged Severe Lower Limb Ischemia to Avoid Ischemic Damage - The First Clinical Experience

“…In heart surgery topical hypothermia is still used for myocardial protection (1)(2)(3). There are only sporadic publications on the experimental use of topical hypothermia to protect skeletal muscle, for example: musculo-cutaneous flaps (4,5); isolated gracilis muscle (6); and post-ischemic hypothermia to diminish ischemic damage (7,8).…”

Myocardial ultrastructural changes during extracorporeal circulation wtih anoxic cardiac arrest and its prevention by coronary perfusion. Experimental study.

“…These include continuous hypothermic coronary perfusion (Hirose and Bailey, 1969); intermittent coronary perfusion with hypothermic blood (Ebert et al, 1962) or with normothermic blood (Benzing et al, 1973); low-pressure coronary perfusion (Brown et al, 1969); and topical cardiac hypothermia (Robicsek et al, 1970), although its prolonged application may result in myocardial and pericardial damage. In direct myocardial revascularization retrograde perfusion through the coronary sinus has been employed satisfactorily (Hammond, Davies, and Austen, 1967).…”