Cardiovascular dysfunction in symptomatic primary hyperparathyroidism and its reversal after curative parathyroidectomy: Results of a prospective case control study

Background Cardiovascular mortality in primary hyperparathyroidism (PHPT) is attributed to myocardial and endothelial dysfunction. In this prospective, case-control study we assessed cardiovascular dysfunction in patients with symptomatic PHPT and its reversal after successful parathyroidectomy. Methods Fifty-six patients with symptomatic PHPT underwent two-dimensional echocardiography, tissue Doppler (diastolic function assessment), serum N-terminal pro-brain natriuretic peptide (s-NTproBNP, a myocardial damage marker), and endothelial- and smooth muscle−dependent vasodilatory response (vascular dysfunction) studies before, 3, and 6 months after parathyroidectomy; 25 age-matched controls were studied similarly. Results Patients had greater left ventricular mass (192 ± 70 vs 149 ± 44 g; P = .006), interventricular septal thickness (10.8 ± 2.5 vs 9.0 ± 1.6 mm; P = .001), posterior wall thickness (9.9 ± 2.0 vs 8.6 ± 2.2 mm; P = .004), and diastolic dysfunction (lower E/A trans-mitral flow velocity ratio [1.0 ± 0.4 vs 1.3 ± 0.4; P = .01). Patients had greater s-NTproBNP (4,625 ± 1,130 vs 58 ± 49 pg/mL; P = .002) and lower endothelial-mediated vasodilation (9.3 ± 8.6 vs 11.7 ± 6.3%; P = .03) and smooth muscle−mediated vasodilation (20.1 ± 17.9 vs 23.8 ± 11.2%; P = .01). Improvements in left ventricular mass, systolic and diastolic function, and smooth muscle−mediated vasodilation were noted from 3 to 6 months after parathyroidectomy. Endothelial-mediated vasodilation did not improve significantly. S-NTproBNP levels mirrored echocardiographic changes with a substantial, sustained decrease. Results were similar in hypertensive and normotensive patients. Conclusion Symptomatic PHPT patients have substantial cardiac and vascular dysfunction, which improve by 6 months after parathyroidectomy. Objective cardiovascular evaluation may improve outcomes in symptomatic PHPT patients.