Related Experiment Videos
Calcium-antagonists in preventing restenosis following coronary angioplasty
1Abteilung Kardiologie, Angiologie und Pulmologie, Universität Heidelberg, Germany.
Abstract:
In experimental studies the growth factor dependent proliferation and migration of medical smooth muscle cells was found to be inhibited by calcium-antagonists. Since this process seems to play an important role in the pathogenesis of recurrent stenosis, clinical trials were performed to evaluate the influence of calcium-channel blockers on restenosis rate after initially successful coronary angioplasty. However, according to the first 3 completed studies the restenosis rate was not decreased significantly either by the treatment with nifedipine or by the treatment with different dosages of diltiazem. The influence of high-dose verapamil treatment (Isoptin RR, 240 mg verapamil, twice daily) on the recurrence of coronary obstruction has been investigated by a recently completed prospective double-blind, placebo-controlled trial (VAS) which included 196 consecutive patients with at least one risk factor for restenosis. Patients with stable angina pectoris (n 75) and patients with unstable angina/non Q-wave infarction (n 97) were randomized separately. Follow-up angiography within 6 months after the procedure was performed in 88% of the recruited patients. Another 22 patients (11%) stopped the study medication before control angiography. At present, detailed data of the intention-to-treat analysis and the as-treated analysis of the results of VAS were submitted for publication.
Insights
Calcium-channel blockers, like nifedipine and diltiazem, did not significantly reduce restenosis after coronary angioplasty. High-dose verapamil
Area of Science:
- Cardiology
- Pharmacology
Background:
- Smooth muscle cell proliferation and migration are implicated in restenosis after coronary angioplasty.
- Calcium-antagonists have shown inhibitory effects on these cellular processes in experimental studies.
Purpose of the Study:
- To evaluate the efficacy of high-dose verapamil in preventing restenosis after coronary angioplasty.
- To assess the impact of verapamil on coronary obstruction recurrence in patients with restenosis risk factors.
Main Methods:
- A prospective, double-blind, placebo-controlled trial (VAS) involving 196 patients.
- Separate randomization for patients with stable angina pectoris and unstable angina/non Q-wave infarction.
- Follow-up angiography performed in 88% of patients within 6 months.
Main Results:
- Previous studies with nifedipine and diltiazem did not show significant reduction in restenosis rates.
- Detailed intention-to-treat and as-treated analyses of the VAS trial are pending publication.
Conclusions:
- Nifedipine and diltiazem treatments were ineffective in reducing restenosis rates post-coronary angioplasty.
- The efficacy of high-dose verapamil (VAS trial) in preventing coronary obstruction recurrence requires further analysis and awaits publication.