Brief Answer:
Yes diltiazem can precipitate congestive cardiac failure.

Detailed Answer:
Hi,
Firstly thanks for choosing health care magic for your query!

As per your query ,
Diltiazem is a nondihydropyridines calcium channel blocker,usually used to treat angina and hypertension.As you say you had a myocardial infarction ,i would like to tell you that diltiazen has no role in treatment or medical stabilisation of patient post myocardial infarction ,infact it can further worsen your cardiac symptoms by precipitating congestive cardiac failure;rather calcium channel blocker from dihydropyridine group like amlodipine are much safer and superior to diltiazem and they are less likely to precipitate congestive cardiac failure.

You have written heart attack caused by heart spasm,please be more specific ,as these words are very important as there is another entity called micro vascular angina.Coronary MVD is heart disease that affects the heart's smallest coronary artery blood vessels. Causes of microvascular angina: Spasms within the walls of these very small arterial blood vessels causes reduced blood flow to the heart muscle leading to a type of chest pain referred to as microvascular angina.In treatment of microvascular angina Diltiazem is used frequently.

So if possible try to make your question more clear or attach all test reports done by your cardiologist to diagnose that it was a heart attack.

For you question ,yes if heart attack was due to blockage in coronary artery then diltiazem can precipitate congestive cardiac failure .

Thanks!

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