The efficacy of retrograde coronary venous delivery of procainamide for the management of spontaneous and inducible sustained ventricular tachycardia was evaluated and compared with systemic intravenous procainamide administration in 22 conscious dogs with permanent left anterior descending coronary artery occlusion. Selective retrograde injection of procainamide was achieved through an autoinflatable balloon catheter placed in the great cardiac vein, with the tip positioned in the vicinity of the site of left anterior descending coronary occlusion. Great cardiac vein retroinfusion of procainamide was significantly (p < 0.05) more effective than systemic intravenous injection against spontaneous ventricular tachycardia I day after coronary artery occlusion (13 dogs) and against electrically induced sustained ventricular tachycardia in the 3 to 12 day postocclusion period (9 dogs). Significantly lower doses of procainamide were used with retroinfusion as compared with systemic administration, that is, 19.6 ± 8.8 versus 35 ± 0 mg/kg body weight during spontaneous tachycardia and 13.4 ± 4.1 versus 32.1 ± 2 mg/kg during induced tachycardia (p < 0.01). Retroinfusion of saline solution through the great cardiac vein had no effect on either type of tachycardia. Myocardial tissue procainamide levels measured in infarcted and ischemic zones of the left anterior ventricular wall were 9 to 100 times higher after great cardiac vein retroinfusion than after systemic injection. Great cardiac vein dye injection studies demonstrated a preferential distribution in left ventricular regions supplied by the occluded coronary artery.

It is concluded that regional coronary venous procainamide retroinfusion in dogs with myocardial infarction is more effective than systemic intravenous injection against both spontaneous and inducible sustained ventricular tachycardia. The greater efficacy of great cardiac vein treatment appears to be primarily related to selectively increased delivery of procainamide to ischemic myocardial sites.