Humoral Determinants of the Left Ventricular Function in Pheochromocytoma Patients

Abstract

In an attempt to characterize the hemodynamic diversity of adaptation to chronic catecholamine exposure and to determine a possible link between the tumor humoral activity and left ventricular (LV) systolic and diastolic function, mitral flow Doppler, and echo indexes were calculated and urinary adrenaline, noradrenaline (NA), and dopamine levels determined in 25 patients with pheochromocytoma. Pheochromocytoma patients had higher LV contractility quantified by the ratio of systolic blood pressure to endsystolic LV volume/body surface area (8.2 ± 3.2 vs. 5.5 ± 1.5 mm Hg•m^2/ml; p < 0.001) and LV mass index (113.4 ± 41.4 vs. 88.9 ± 15 g/m^2, p < 0.01) than healthy controls of similar age and sex distribution. End-systolic LV wall stress showed wide scatter, with some very high values not compensated by LV hypertrophy. Mitral flow Doppler indicated impaired early LV filling in pheochromocytoma patients vs. controls: lower early-to-late mitral flow velocity integral ratio (1.9 ± 0.9 vs. 2.7 ± 0.9, p < 0.001) and maximal early-to-late mitral flow velocity ratio (Ev/Av; 1.2 ± 0.6 vs. 1.7 ± 0.4, p < 0.005). Dopamine correlated inversely with LV mass (r = -0.44, p < 0.05) and blood pressure (systolic r = -0.39, p < 0.05; diastolic r = -0.57, p < 0.05). NA correlated with Er/Ar (r = 0.44, p < 0.05). In patients with pheochromocytoma the mitral inflow profile indicates impaired LV relaxation, but NA may play a role in enhancing early LV filling.