Exercise-induced paroxysmal atrioventricular block during nuclear perfusion stress testing: evidence for transient ischemia of the conduction system.

Abstract

Nuclear myocardial perfusion imaging provides noninvasive evidence that transient ischemia of the posteroseptal segment, anatomically corresponding to the His bundle, can result in paroxysmal AV block in patients with severe right coronary artery and chronic infranodal conduction disturbances. The demonstration of the underlying pathophysiological mechanism is useful for selecting the most effective treatment strategy.