Factors affecting left ventricular synchronicity in hypertensive patients: are arterial stiffness and central blood pressures influential?

OBJECTIVES
Left ventricular (LV) dyssynchrony is a common finding in patients with hypertension and is associated with LV hypertrophy. Arterial stiffness (AS) and central (aortic) blood pressures play a significant role in end-organ damage such as LV hypertrophy caused by hypertension. The objective of this study was to investigate the relationship between AS, central blood pressures (BP) and LV dyssynchrony.

STUDY DESIGN
Thirty-five newly diagnosed hypertensive patients and 40 controls were enrolled in the study. The entire study population underwent a comprehensive echocardiographic study including tissue synchrony imaging. The 12 segmental model was used to measure the time to regional peak systolic tissue velocity (Ts) in the LV and two dyssynchrony indices were computed. Parameters of AS including pulse wave velocity (PWV), augmentation index (AIx@75), and central systolic and diastolic BP were evaluated by applanation tonometry.

RESULTS
The baseline clinical and echocardiographic parameters of both groups were similar except for their BPs. Dyssynchrony indices were prolonged in patients with hypertension as compared to the controls. The standart deviation of Ts of 12 LV segments in patients with hypertension and the controls were 48.7±18.8 vs. 25.8±13.1, respectively (p<0.001), and the maximal difference in Ts between any 2 of 12 LV segments was 143.9±52.2 for hypertension patients vs. 83.8±39.4 for controls (p<0.001). PWV (11.9±2.5 vs. 9.5±1.4, p<0.001), AIx@75 (27.4±8.3 vs. 18.3±9, p=0.009), and central systolic (147.6±20.8 vs. 105.4±11, p<0.001) and diastolic (99.8±14.4 vs. 72.8±9.5, p<0.001) pressures were higher in patients with hypertension than in the controls, respectively. In multivariable analysis, central systolic BP (β=0.496, p=0.03), LV mass index (β=0.232, p=0.027), and body mass index (β=0.308, p=0.002) were found to be independently related to dyssynchrony.

CONCLUSION
Central systolic BP is an independent predictor of LV dyssynchrony, but AIx@75 did not have an independent effect on LV synchronicity in patients with newly-diagnosed hypertension.