Calcium Channel Blockers in Restoration of Endothelial Function: Systematic Review and Meta-Analysis of Randomized Controlled Trials

Background: Clinical evaluation of the Endothelial Function (EF) is becoming an essential step in the quality assessment of cardiovascular risk prevention and rational pharmacotherapy of cardiovascular disorders. The existing pieces of evidence suggested that Calcium Channel Blockers (CCB) can induce positive effects on impaired EF. Objective: To evaluate the effects of CCB on EF, we performed a meta-analysis of available data from randomized and placebo-controlled or other treatment-controlled clinical studies encompassing effects of CCB on EF, as measured by Flow-Mediated Dilation (FMD) of the brachial artery. Methods: The relevant clinical studies were searched by systematic exploration of the appropriate databases until November 30, 2017. A random-effect model was conducted. The primary outcome was the percentage change in FMD between the baseline and the final levels in response to investigated drugs. Results: Fifteen randomized clinical studies with 33 arms were identified. CCB improved FMD more pronounced than thiazide diuretics - TD (3 studies, 157 participants, WMD=2.08%, 95% CI=0.35-3.80%; P=0.02). Oppositely, ACE Inhibitors (ACEI) and Angiotensin Receptor Blockers (ARB) notably improved FMD if compared to CCB (CCB vs. ACEI: 5 studies, 533 participants, WMD = -1.62%, 95% CI = -2.74% to -0.50%; P=0.005; and CCB vs. ARB: 9 studies, 669 participants, WMD = -1.52%, 95% CI = -2.22% to -0.81%; P=0.0001). CCB effects on EF were similar to those evoked by beta blockers or placebo. Conclusion: CCB improved EF to a more prominent extent only if paralleled to TD, while inversely; ACEI and ARB were more effective in augmenting FMD.