Background: Syndrome X is defined as typical angina pectoris, positive treadmill exercise test, negative intravenous ergonovine test, and angiographically normal coronary arteries.
Hypothesis: In the present study, we investigated the anti-ischemic and antianginal effects of nisoldipine and ramipril in patients with syndrome X.
Methods: After 2 weeks of the first wash-out period, 18 patients (7 men, 11 women, age 46 +/- 10 years) were given nisoldipine (NIS) 5 mg twice daily for 4 weeks, and after 2 weeks of the second wash-out period, the same patients were given ramipril (RAM) 2.5 mg once daily for 4 weeks. A treadmill exercise test with modified Bruce protocol was performed at the end of each period.
Results: The time to angina in exercise (607 +/- 115 s-650 +/- 117 s, p = 0.006, vs. 630 +/- 114 s-660 +/- 123 s, p = 0.02), total exercise time (612 +/- 110 s-656 +/- 114 s, p = 0.0008, vs. 630 +/- 114 s-660 +/- 123 s, p = 0.02), and maximum MET value (11.09 +/- 2.08-11.86 +/- 2.04, p = 0.0016, vs. 11.42 +/- 2.09-12.2 +/- 2.26, p = 0.01) were increased significantly with both therapy modalities. The time to 1 mm ST-segment depression (123 +/- 93 s-220 +/- 172 s, p = 0.002) was increased significantly with NIS therapy. The time to ST-segment recovery (434 +/- 268 s-330 +/- 233 s, p = 0.016 vs. 443 +/- 289 s-370 +/- 278 s, p = 0.012), the frequency of anginal attacks per week (1.27 +/- 1.4-0 +/- 0.38, p = 0.005, vs. 1 +/- 1.32-0.33 +/- 0.59, p = 0.028), and the need for sublingual nitroglycerin (1.16 +/- 1.29-0.11 +/- 0.32, p = 0.005, vs. 0.94 +/- 1.16-0.27 +/- 0.57, p = 0.012) were decreased significantly with both drugs.
Conclusion: We observed that 10 mg daily NIS and 2.5 mg daily RAM have similar anti-ischemic and antianginal effects in patients with syndrome X.