Renewed efforts are under way to apply clinically oriented coronary venous retroperfusion methods for treatment of myocardium jeopardized by major coronary artery obstructions. Based upon improved understanding of criteria for retroperfusion effectiveness and safety, improved arterial blood retroperfusion and pharmacologic agent retroinfusion techniques have been demonstrated to provide significant myocardial infarct salvage and enhance cardiac function. The retrograde systems also have a potential for prompt lysis of an acute coronary artery thrombus and for treatment of refractory arrhythmias. Retroperfusion may constitute an effective protective support when used in conjunction with new aggressive interventions, maintaining jeopardized myocardial viability and function pending permanent reversal of a severe coronary flow insufficiency or emergency revascularization in evolving acute infarction. Clinical applications are anticipated in the setting of unstable angina and arrhythmias, as circulatory assist during complex coronary angioplasty and thrombolytic procedures, and as adjunct support of cardiac surgery.