Clinical efficacy of benidipine for vasospastic angina pectoris.
BACKGROUND
Most patients with vasospastic angina who have no significant organic coronary arterial stenosis are well controlled by medical therapy and the prognosis is almost satisfactory. Calcium channel (Ca) blockers are used as the first choice and effective agents for vasospastic angina pectoris. However, they do not always work well. Some uncontrolled coronary vasospasms would happen to cause prolonged occlusion of coronary artery resulting in myocardial infarction, life-threatening arrhythmias and sudden death. Therefore, it is very important to pay attention to such a refractory coronary spasm and choose the most effective agent out of Ca blockers for the treatment of each patient with vasospastic angina attacks. This study was designed to evaluate the anti-vasospastic efficacy of benidipine, a long acting dihydropyridine (DHP) Ca blocker, in patients with other Ca blockers-resistant angina.


METHODS
Patients treated with diltiazem but not enough to control angina attacks were enrolled in the present study. Treatment with diltiazem (CAS 33286-22-5, 42399-41-7) was changed to treatment with benidipine (CAS 91599-74-5) and the parameters such as angina frequency, duration, blood pressure, heart rate, electrocardiogram and hematological parameters (serum NO(x), plasma cGMP) were measured and compared.


RESULTS
Fifteen patients with vasospastic angina were enrolled. After switching from diltiazem to benidipine, angina attacks were completely disappeared in six patients. Although the frequency was not decreased, the average duration of attacks was shorter than before in three patients. Four patients did not improve and two patients obviously worsened. In the improved nine patients, serum nitrite/nitrate (NO(x)) levels showed a significant increase from 37.6 +/- 15.3 to 54.5 +/- 26.7 pmol/L (p < 0.05) and cGMP levels subsequently elevated from 2.2 +/- 0.8 to 2.5 +/- 0.6 micromol/L (p = 0.05) after benidipine therapy started. Adverse effects such as hypotension and bradycardia were not observed.


CONCLUSIONS
This study suggests that benidipine may be helpful in Japanese patients with vasospastic or variant angina pectoris, if diltiazem was not successful.
Suzuki
Hiromasa
H
Department of Cardiology, Juntendo University School of Medicine, 2-1-1, Hongo, Bunkyo-ku, Tokyo 113-8421, Japan. hisuzuki@med.juntendo.ac.jp
Yokoyama
Ken
K
Akimoto
Yoshinori
Y
Daida
Hiroyuki
H
D000368:Aged; D000787:Angina Pectoris / Q000150:complications / Q000188:drug therapy* / Q000503:physiopathology; D001794:Blood Pressure / Q000187:drug effects; D002121:Calcium Channel Blockers / Q000627:therapeutic use*; D003329:Coronary Vasospasm / Q000188:drug therapy* / Q000209:etiology / Q000503:physiopathology; D006152:Cyclic GMP / Q000097:blood; D004095:Dihydropyridines / Q000627:therapeutic use*; D004110:Diltiazem / Q000627:therapeutic use; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D008297:Male; D008875:Middle Aged; D009569:Nitric Oxide / Q000097:blood; D017211:Treatment Failure; D016896:Treatment Outcome; D014665:Vasodilator Agents / Q000627:therapeutic use*
D002121:Calcium Channel Blockers; D004095:Dihydropyridines; D014665:Vasodilator Agents; D009569:Nitric Oxide; C061004:benidipine; D004110:Diltiazem; D006152:Cyclic GMP