Baroreflex sensitivity correlates with left ventricular morphology and diastolic function in essential hypertension.

OBJECTIVES: Arterial hypertension is a common cause of cardiac organ damage, inducing morphological and functional modifications. Spontaneous baroreflex sensitivity (BRS) control of the heart rate is a key mechanism of blood pressure homeostasis, and is impaired in patients with hypertension. This study sought to assess the association between BRS and left ventricular morphology and function.
METHODS: We studied 224 hypertensive patients (125 men; aged 47.8 +/- 10.8 years, mean +/- SD) compared with 51 normotensive control subjects (25 men, aged 45.7 +/- 12.5 years). Left ventricular morphology, systolic and diastolic function were evaluated by echocardiography. Spontaneous BRS was measured using the sequence method.
RESULTS: BRS was inversely associated with relative wall thickness (R = 0.17; P < 0.0001) and left ventricular mass index (R = 0.03; P = 0.01); in particular, BRS was significantly impaired in patients with concentric left ventricular remodelling (median [interquartile difference] 9.4 [4.1]) and hypertrophy (9.05 [3.9]) compared with the normal left ventricle (12.3 [5]; P < 0.001). BRS showed a significant association with systolic function evaluated by midwall fractional shortening (r = 0.28; P < 0.001), stroke volume (r = 0.27; P < 0.001), stroke work (r = 0.17; P < 0.05), and fractional shortening (r = 0.17; P < 0.05). BRS was significantly decreased in patients with diastolic dysfunction; it was lower in patients with diastolic dysfunction compared with both the control group and hypertensive patients with normal diastolic function.
CONCLUSION: BRS is associated with left ventricular morphology, systolic and diastolic function in hypertensive patients. In particular BRS is impaired in patients with diastolic dysfunction. These findings suggest a role for BRS as a target in arterial hypertension.