To compare the anti-inflammatory and endothelial progenitor cell mobilizing effects of ramipril and telmisartan in patients presenting with acute coronary syndrome (ACS), 42 patients with ACS were randomized after successful percutaneous coronary intervention to ramipril 5 mg/day (22 patients) or telmisartan 80 mg/day (20 patients). Peripheral blood samples were drawn at baseline and at 20 days to measure high-sensitivity C-reactive protein and to assess 4 populations of progenitor cells by flow cytometry, namely CD34+/KDR+, CD34+/CD133+, CD34+/CD133+/CD45-, and CD34+/KDR+/CD45- cells. High-sensitivity C-reactive protein levels, similar in the 2 groups at baseline, were significantly more decreased by telmisartan than by ramipril at follow up (p = 0.013 for time-by-drug interaction). The main effect for time was also significant (p <0.001). CD34+/KDR+ and CD34+/CD133+ cells were similar at baseline and did not change over time (p = 0.2 and p = 0.1, respectively). In contrast, for CD34+/KDR+/CD45- and CD34+/CD133+/CD45- cells, a significant increase with time was seen (p = 0.02 and p = 0.002, respectively) and no differential effect of either drug was seen. In conclusion, telmisartan shows a more potent anti-inflammatory effect than ramipril after an ACS. The 2 drugs do not show a differential effect on endothelial progenitor cell mobilization.
Trial registration: ClinicalTrials.gov NCT00702936.