Targeted treatment reverses increased left cardiac work in unilateral versus bilateral primary aldosteronism.

Abstract

The incidence of cardiovascular complications may be higher in unilateral than in bilateral primary aldosteronism (PA). We compared non-invasive hemodynamics before and after targeted therapy of bilateral versus unilateral PA. Adrenal vein sampling was performed, and cardiovascular variables were recorded using radial artery pulse wave analysis and whole-body impedance cardiography (n=114). In a subset of 40 patients (adrenalectomy n=20, spironolactone-based treatment n=20), hemodynamic recordings were again performed after 33 months of targeted PA treatment. In initial cross-sectional analysis, 51 patients had bilateral and 63 had unilateral PA. The mean ages were 50.6 and 54.3 years (p=0.081), and body mass indexes were 30.3 and 30.6kg/m2 (p=0.724), respectively. Aortic blood pressure and cardiac output did not significantly differ between the groups, but evaluated left cardiac work was ~10% higher in unilateral PA (p=0.022). In the followup study, initial and final blood pressure levels in the aorta were not significantly different, while initial cardiac output (+13%, p=0.015) and left cardiac work (+17%, p=0.009) were higher in unilateral than in bilateral PA. After a median treatment time of 33 months, the differences in cardiac load were abolished, and extracellular water volume was reduced by 1.3 and 1.4 liters in bilateral versus unilateral PA, respectively (p=0.814). These results suggest that unilateral PA burdens the heart more than bilateral PA, providing a possible explanation for the higher incidence of cardiac complications in unilateral disease. A similar reduction in aldosterone-induced volume excess was obtained with targeted surgical and medical treatment of PA.