Atrioventricular Block in a Long-Term Dialysis Patient: Reversal After Parathyroidectomy

WITH THE advent of hemodialysis for patients with end-stage renal disease, medical complications not previously encountered, including advanced secondary hyperparathyroidism with resultant metastatic calcifications, have developed. 1-6 Cardiac calcifications have been reported previously as an autopsy finding, with some leading to refractory fatal cardiac arrhythmias. 1-5 Our patient had first-degree heart block, possibly as a result of metastatic cardiac calcification that completely reversed to normal sinus rhythm two months after a total parathyroidectomy. Report of a Case A 20-year-old man with end-stage renal disease secondary to chronic pyelonephritis and vesicoureteral reflux began hemodialysis treatments in July 1971. On Aug 2, 1973, he was admitted to the hospital for the revision of an arteriovenous fistula because of recurrent episodes of high-output cardiac failure. An electrocardiogram on Aug 3 demonstrated first-degree heart block with a PR interval of 0.24 seconds. The ventricular rate was 100 beats per minute, and there was evidence