Influence of vascular remodelling and reduced heart rate variability at indapamide efficacy in patients with arterial hypertension

Till nowadays, the correlation between autonomic regulation of heart and the severity of essential arterial hypertension (AH) in patients receiving long-term antihypertensive therapy has not been sufficiently studied.

The aim: to evaluate the efficacy of indapamide retard depending on the presence of vascular remodelling and heart rate variability (HRV) in case of uncomplicated essential hypertension clinical course.

Material and methods. 75 patients (43 males and 32 females) aged from 48 to 60 years (average age 56,3±6,4 years) with I–II stage of arterial hypertension were examined. Doppler echocardiography, Doppler ultrasound examination of the brachial artery (BA), 24-hour blood pressure (BP) monitoring and Holter ECG monitoring were performed. The dynamics of BA wall remodeling indicators, endothelium-dependent vasodilation (EDVD) and heart rate variability (HRV) were estimated before and after 6 months of monotherapy with indapamide retard 1,5 mg/day. The patients were divided into two groups: 30 persons without signs of structural and functional remodelling of BA (group 1) and 45 with hypertrophy of BA wall and/or endothelial dysfunction (group 2).

Results. It was found that the initial HRV indicators, characterizing sympathetic nervous system hyperactivity, were significantly different in the compared groups. Indapamide retard at a dose of 1,5 mg/day had a fairly high and comparable antihypertensive effect in both groups, however, in group 2 during therapy there was a significant decrease in the thickness of the intima-media complex by an average of 12,8% (p=0,013) and, conversely, an increase in endothelium-dependent vasodilation by an average of 25,4% (p <0,001). As a result, specific peripheral vascular resistance decreased by an average of 17,1% (p=0,002). In both groups, patients with left ventricular hypertrophy showed a significant decrease in the left ventricular myocardial mass index: in group 1 – by an average of 10,4% (p=0,021), in group 2 – by 13,4% (p=0,007). Changes of HRV indexes during indapamide retard therapy in both groups were statistically insignificant, although they tended to improve the vagosympathetic balance. A direct correlation between standard deviation of R–R intervals (SDNN) and EDVD index (r=0,34; p=0,007) was fixed.

Conclusion. It has been shown that the intensity of vasoprotective effect of indapamide retard correlates with the severity of vascular remodelling and/or endothelial dysfunction in patients with essential hypertension, which also manifests itself in the absence of autonomic sympathetic hyperactivity.