Effect of chronic hypercalcemia on the heart. An analysis of 18 necropsy patients.

Certain clinical and morphologic cardiac observations are described in 18 necropsy patients, aged 33 to 58 years (mean 45 years) (14 women), with chronic hypercalcemia (11.6 to 34.4 mg/dl [19.4]) from one to nine years (mean five years). Primary hyperparathyroidism was present in nine patients and secondary hyperparathyroidism in the other nine (of renal origin in seven). Cardiac valve anular and coronary arterial calcific deposits were present in 10 patients (Group I) including four (mean age 51 years) with considerable narrowing of two or three of the four major epicardial coronary arteries. None of the other eight patients (Group II) had cardiac valve anular or cuspal calcific deposits; only two had coronary calcific deposits, small in each, and none had significant coronary luminal narrowing. Calcium was in the media ("medial calcinosis"), with or without intimal deposition, of the coronary arteries in five patients. Comparison of the patients in Group I to those in Group II disclosed similar mean ages, durations of hypercalcemia and serum calcium levels, but significantly (p less than 0.05) higher mean total serum cholesterol levels (216 versus 163 mg/dl) and heart weights (426 versus 320 g). This study demonstrates that chronic hypercalcemia is associated with accelerated deposition of calcium in the cardiac anuli and valvular cusps, in the media and intima of the coronary arteries and in individual myocardial fibers (dystrophic calcification), and that coronary intimal calcification may be associated with or produce luminal narrowing, especially in patients with serum total cholesterol levels over 200 mg/dl. Thus, chronic hypercalcemia may be viewed as a "risk factor" to accelerated coronary atherosclerosis.