S. Denchev 1, I. Simova 2, S. Dimitrov 3 and N. Semerdzhieva
1 Clinic of Cradiology, Medical Institute of the Ministry of Internal Affairs – Sofia
2 Cardiology Division, “City Clinic” – Sofia
3 Divisin of Invasive Diagnostics, MHAT “Hristo Botev” – Vratza
Purpose: Our purpose was testing the possibility for correlation between endothelium-independent coronary function and flow-mediated dilation of brachial artery (FMD) and evaluation of their prognostic significance in patients with non-оbstructive coronary disease. Material and methods: The vasodilatory response of left anterior descending coronary artery (LAD) to intracoronary nitroglycerin (NTG) was assessed and matched with the results of the ultrasound evaluation of brachial artery FMD in a group of 153 patients with non-obstructive coronary atherosclerosis and recurrent ischaemia. Results: In the setting of non-obstructive disease the frequency of endothelium-independent coronary macrovascular dysfunction (MAVCD) was 32.9% (n = 46). The mean values of FMD in our group were 7.97± 5.71% and only insignificantly differ in relation to the presence of coronary atherosclerosis on angiography. The examined two methods for vascular function assessment did not correlate substantially (r = -0.010; р = 0.925) and were not associated with the adverse events incidence during seven-year follow-up (6.58 ± 4.45% vs 8.77 ± 6.71%, p = 0.252 for FMD; 54.7% vs 45.4%, p = 0.992 for MАVCD). The impairment of FMD in the group with angiographic signs of coronary atherosclerosis showed borderline significant correlation with coronary flow delay following intracoronary injection of NTG (r = - 0.292, p = 0.057). Conclusion: In patients with angina and non-obstructive atherosclerosis the extent of coronary dilation in response to NTG does not correlate substantially with brachial artery FMD. The significance of peripheral vascular dysfunction as marker of impaired coronary flow in non-obstructive coronary disease needs evaluation in larger cohorts.
Кey words: coronary dysfunction, nitroglycerin, coronary flow, flow-mediated vasodilation
Address for correspondence: Prof. S. Denchev, MD, PhD, Clinic of Cardiology, Medical Institute of the inistry of Internal Affairs, 79, General Skobelev Blvd., Bg – 1606 Sofia