Yes. Most experience has been with verapamil. By depressing myocardial contractility, verapamil can decrease the left ventricular outflow gradient. It also improves diastolic filling by improving myocardial relaxation. Exercise capacity and overall symptoms are often improved.
Are calcium channel blockers useful in the reduction of left ventricular hypertrophy caused by hypertension?
Yes. Numerous studies have shown that calcium channel antagonists reduce left ventricular mass and improve pathophysiologic sequelae, such as ventricular dysrhythmias, impaired ventricular filling, and coronary reserve, while maintaining left ventricular pump function. It remains to be seen, however, whether a reduction in the degree of left ventricular hypertrophy will ultimately reduce the risks of sudden death, acute myocardial infarction, and congestive heart failure associated with hypertensive heart disease.
Why are calcium channel antagonists frequently used in patients undergoing percutaneous transluminal coronary angioplasty (PTCA)?
Calcium channel antagonists may prevent coronary spasm which is frequently seen during and shortly after PTCA and other percutaneous coronary interventions. They have not been shown, however, to reduce the incidence of restenosis, which usually occurs within the first 6 months after PTCA.
Are there any studies suggesting benefit of calcium channel antagonists in the prevention of coronary atherosclerosis?
Yes. Some preliminary information suggests that calcium blockers may affect the atherosclerotic process. The Montreal Heart Institute Trial with nicardipine showed less progression of stenotic lesions that are 20% in severity. In the International Nifedipine Trial on Antiatherosclerotic Therapy (INTACT), nifedipine reduced the rate of appearance of new coronary lesions. In both trials, however, no effect was seen on the overall progression or regression of atherosclerosis. Other preliminary data also suggest that diltiazem may slow the development of accelerated coronary atherosclerosis often seen in heart transplant recipients. At this time, there is not general agreement on the use of calcium channel blockers for this indication.