Assessment of left ventricular dyssynchrony in dipper and non-dipper hypertension

Background. Ventricular dyssynchrony is an co-determinant of progression and exacerbation of heart failure (HF). The co-existence of ventricular dyssynchrony with hypertension (HT) and HF were shown, however there is no data regarding the effect of circadian rhythm of blood pressure (BP) on ventricular synchrony. Therefore, we aimed to study the left ventricular synchrony in dipper and non-dipper normotensive and hypertensive participants. Methods. Participants (n = 142) were categorized into four groups as "Normotensive-Dipper" (NT-D) (n = 40), "Normotensive-Non-dipper" (NT-ND) (n = 30), "Hypertensive-Dipper" (HT-D) (n = 38) and "Hypertensive-Non-dipper" (HT-ND) (n = 34). Left ventricular dyssynchrony was investigated by color-coded tissue Doppler imaging. Results. Non-dippers had higher 24-h and night-time BP both in normotensives and hypertensives. The incidence of ventricular dyssynchrony (a Ts-SD-12 > 34.4 ms) was higher in the hypertensive group (47.2% vs 24.3%, p = 0.005). The frequency of ventricular dyssynchrony was higher in the HT-ND group than the HT-D group (58.8% vs 36.8%, p = 0.05); however, the frequency of ventricular dyssynchrony was similar among the normotensives (26.7% vs 22.5%, p = 0.45). Ts-SD-12 and Ts-12 were higher in NT-ND group than the NT-D group. Conclusions. Non-dipping BP pattern was associated with impaired left ventricular contraction synchrony in both normotensive and hypertensive participants, which may be related with short-and long-term effects of HT on myocardium.