The role of collateral blood supply in ventricular tachycardia after myocardial infarction.

The hypothesis that collateral or anterograde blood supply to an infarcted area maintains blood supply to cells responsible for ventricular tachycardia after myocardial infarction was studied in six patients. All patients had suffered a myocardial infarction and developed spontaneous episodes of sustained monomorphic ventricular tachycardia. The arrhythmia was paroxysmal in three patients and incessant in the other three. During ventricular tachycardia iced isotonic saline (10 ml in approximately 4 s) was injected first in the coronary artery ostia and thereafter superselectively in the coronary artery providing collateral or anterograde blood supply to the infarcted area. A 2.5-F catheter was used superselectively to catheterize coronary arteries of approximately 2-3 mm lumen for that purpose. Three patients had anterograde blood supply to the infarcted area through a reperfused infarct-related vessel. Two patients had only collateral retrograde blood supply to the infarcted region. One patient had both anterograde and retrograde collateral blood supply to the area of infarction. Ventricular tachycardia was not terminated in any patient during non-selective injection of iced saline in the coronary ostia. In five of the six patients ventricular tachycardia was terminated by the superselective administration of iced saline. The morphology of ventricular tachycardia was changed many times, but did not terminate, in the remaining patient. Termination or change in morphology was achieved during administration of iced saline through collateral vessels in two patients through the coronary artery supplying anterograde flow in three patients and both through collaterals and anterograde flow in the remaining patient.(ABSTRACT TRUNCATED AT 250 WORDS)