Myocardial Infarction under age 40: Risk factors and Coronary Arteriographic findings

Objective: To evaluate risk factors and arteriography findings in young patients under 40 year of age admitted with first acute myocardial infarction (AMI). Design: A prospective descriptive study. Place and Duration of Study: Cardiology Department, Allama Iqbal Medical College/ Jinnah Hospital, Lahore from July 2002 to June 2003. Patients and Methods: During the study period, 274 patients with first AMI were admitted in our coronary care unit and 52 (19%) were under 40 year of age. These 52 patients underwent pre-discharge coronary arteriography. Results: Forty-five (87%) were male and seven (13%) were female. Risk factors in all study patients were smoking in 79%, systemic hypertension in 35%, diabetes mellitus in 31%, hyperlipidemia in 19% and family history of premature coronary artery disease in 17%. Risk factors were distinctly less frequent in patients without coronary atherosclerosis. Cigarette smoking was the main risk factor in male patients while diabetes and hypertension were main risk factors in female patients. Forty-six patients (88%) had significant CAD (greater than 50% diameter narrowing of at least one major coronary artery), 5(10%) had normal coronary arteries and one patient (2%) had marked coronary ectasia. In patients with significant coronary artery disease, the prevalence rate of one, two and three vessel disease was 52, 28 and 20 percent, respectively. No patient had congenital coronary anomaly or significant left main CAD. Conclusion: AMI in persons under the age of 40 years accounts for approximately 19% of AML In this age group, AMI is a disease of men who smoke & single vessel CAD predominates. Approximately half of the young patients have single vessel coronary disease, and in up to 10%, the cause is not related to atherosclerosis. Coronary angiography may be warranted in young patients with AMI to define the anatomy of the disease and to permit optimal management