Background Myocardial Infarction (MI), also known as heart attack, is one of the most common cardiovascular diseases. Although certain drugs or mechanical means are used, day by day natural products such as herbs and spices based MI treatment is getting much popularity over the drugs or mechanical means for their pharmacological effects and have low or no side effects. This study was designed to assess the cardio-protective effect of methanolic extract of Bangladeshi multi clove garlic (Allium sativum) cultivar, a highly believed spice having cardioprotective activity, against isoproterenol (ISO) induced MI through cardiac histopathology as well as cardiac apoptotic caspase-3 gene expression study in female Wistar albino rats. Four groups containing 35 rats treated with respective agents like distill water / garlic extract (200 mg/kg-body-weight/day) up to 28 days and normal saline / ISO (100 mg/kg-body-weight/day) on 29th and 30th day were sacrificed (two rats/group/sacrifice) on the day 31, 46 and 61 and collecting the heart, cardiac histology and gene expression analysis were performed. Results ISO induced MI rats pretreated with garlic extract revealed up regulated expression of the cardiac apoptotic caspase-3 gene at the initial stage but finally the expressions gradually getting down regulated along with gradual improving the cardiac damage caused by apoptosis. Furthermore, only garlic extract pretreated rats were found undamaged cardioarchitecture and normal expressions of this gene. Conclusions These findings suggested that garlic extract confers having significant cardioprotective effect and consuming this spice with regular diet may reduce the risk of MI.