Placebo-controlled comparison of captopril, atenolol, labetalol, and pindolol in hypertension complicated by intermittent claudication.

In a six month placebo-controlled cross-over trial twenty patients with hypertension and peripheral arterial disease were randomised to captopril 25 mg twice daily, atenolol 100 mg once daily, labetalol 200 mg twice daily, or pindolol 10 mg twice daily for one month. Although all treatments were equally effective at lowering blood pressure, pain-free and maximum walking distances on a treadmill were decreased by atenolol, labetalol, and pindolol, but not by captopril. Post-exercise calf blood flow availability was impaired by atenolol, labetalol, and pindolol, but not by captopril. Despite ancillary characteristics of cardioselectivity, intrinsic sympathomimetic activity, or combination with alpha-blockade, beta-blockers seem to impair the lower limb circulation in such patients, whereas captopril seems to preserve it, possibly by maintaining the collateral blood supply.