A Case of Transient Hypercalcemia Following Fistulization of a Calcified Mitral Annulus

Abstract

Abstract We report a case of severe symptomatic hypercalcemia that resolved after a short course of therapy of exclusively fluids and furosemide. An extensive workup for metabolic, neoplastic, and drug-induced causes did not provide a possible etiology of the hypercalcemia. After calcium level returned to baseline, the patient was discharged, only to return a week later with multiple embolic strokes of unknown source. The comparison of cardiac imaging obtained during the hospitalization periods established a possible mechanism for both phenomena; the interior caseous cavity of a calcified mitral annulus (CMAC), which was demonstrated on echocardiography during the first hospitalization, disappeared in a subsequent study in the second hospitalization, probably reflecting a fistulization of the structure into the left ventricle. The spill of contents into the bloodstream, over several days presumably, explains the transient increase in calcium, and the embolic events that followed. We hereby demonstrate a clear relationship between the fistulization of a CMAC and hypercalcemia, emphasizing the risks of this valvular pathology, and introducing a rare mechanism for transient and potentially severe hypercalcemia.