Vasomotion of coronary stenoses in response to calcium-entry blockade with nifedipine in patients with hypertension

Background: An excessive vascular tone, mainly at the level of coronary lesions, is recognized as a mechanism of myocardial ischemia, which is relieved by calcium-channel blockers. Because these drugs are also effective in high blood pressure, their use seems ideal when coronary dysfunction and hypertension are associated. The motility of coronary narrowings in hypertension and their responsiveness to calcium blockade, however, are unexplored. Methods: For this purpose, we evaluated, in 37 hypertensive (diastolic pressure of 95 to 115 mm Hg) and 35 normotensive patients, all suffering from effort angina, the vasomotor responses to calcium-channel blockade with nifedipine (10 mg sublingual) of narrowings (≥50% stenosis) of the major epicardial arteries by use of quantitative angiography. Results: After the drug, 13 of 42 segments in patients in the normotensive group (30%) and four of 43 segments in patients in the hypertensive group (10%) showed an increase in minimum luminal diameter of at least 0.5 mm; 10% and 0% of stenotic segments in these respective groups showed a reduction of 0.5 mm or more. Mean luminal diameter increased 0.42 mm (+24% of the baseline value) in normotensive patients and 0.08 mm (+4.5%) in hypertensive patients (P