Verapamil and mild hyperkalemia in hemodialysis patients: A potentially hazardous association

Abstract

During the past 3 years, 3 patients undergoing intermittent hemodialysis (or about to do so) in our hospital developed a third-degree atrioventricular block while being treated with verapamil for blood pressure or supraventricular arrhythmia. In the 3 cases, mild hyperkalemia was concomitant. The medical history of these patients revealed no intrinsic cause of atrioventricular conduction disturbance. We report herein the 3 cases and draw attention to the risks of atrioventricular block in this particular context.

Junctional bradycardia with verapamil in renal failure - care required even with mild hyperkalaemia

“…The type of bradyarhythmia was junctional rhythm in six of the 10 cases 2 . In another report, Verapamil‐related third degree AV block was observed in three haemodialysis patients with K + levels of 6·4, 6·7 and 6·8 m m 9 . In this report, Letavernier et al.…”

“… 9 related the bradyarrhythmias to verapamil therapy in the presence of hyperkalaemia. Ramipril was included in the treatment list of one of the patients 9 …”

“…Verapamil reduces intracellular calcium influx leading to smooth muscle dilatation, decreased cardiac contractility and slowed AV nodal conduction 1 . Verapamil also blocks ATP‐sensitive K + channels 9 . Activation of ATP‐sensitive K + channels is thought to be of value in the protection against AV blockade during cardiac ischaemic episodes 9 .…”

“…Verapamil also blocks ATP‐sensitive K + channels 9 . Activation of ATP‐sensitive K + channels is thought to be of value in the protection against AV blockade during cardiac ischaemic episodes 9 . Furthermore, aprikalim, an ATP‐sensitive K + channel opener has been found experimentally to reverse the hyperkalaemia‐induced contractile dysfunction 9 .…”

“…Activation of ATP‐sensitive K + channels is thought to be of value in the protection against AV blockade during cardiac ischaemic episodes 9 . Furthermore, aprikalim, an ATP‐sensitive K + channel opener has been found experimentally to reverse the hyperkalaemia‐induced contractile dysfunction 9 . Thus, the ATP‐sensitive K + channel blockade by verapamil may increase the vulnerability to AV conduction delay and probably could enhance the deleterious effects of hyperkalaemia.…”