AimThe main aim of this study was to examine the association between periodontitis and increased risk of AMI (acute myocardial infarction) along with prevalence and distribution of two major periodontal pathogens Aggregatibacter actinomycetemcomitans (A. a) and Porphyromonas gingivalis (P. g), in a small tertiary care hospitals of South India. MethodsA total of 30 subjects include experienced Acute myocardial infarction (10 AMI patients, 10 patients with AMI-GCP (Acute Myocardial Infarction – Generalized Chronic Periodontitis) and 10 healthy controls) were studied. The oral examination including the gingival index (GI), plaque index (PI), russel's index (RI), probing pocket depth (PPD) were performed. Subgingival plaque microorganisms were detected with DNA-RNA hybridization by IAI Pado Test 4.5. Biochemical parameters Blood lipids – LDL, HDL, Triglycerides and Total cholesterol, in addition to Cardiac enzymes CPK and CPK-MB were carried out. ResultsThe study demonstrated that patients with AMI-GCP exhibited significantly higher frequency of Probing pocket depths (PPDs) >5 mm than AMI and controls (P < 0.001). Mean probing pocket depth (PPD), Russell's index (RI) were significantly increased among AMI, AMI-GCP than controls (P < 0.001), Hygiene indexes (PI and GI) were also significantly increased among cases with AMI (P < 0.001). All periodontal pathogens were over represented in patients with AMI-GCP and positively correlated with PPD and RI. The total bacterial load A. a (1.151 millions) and P. g (3.451 millions). ConclusionThe present study confirms a significant association between periodontitis and AMI in south Indian population. The total bacterial load of A. actinomycetemcomitans and P. gingivalis may be one of the strong concomitant risk factors in the development of AMI of south Indian population.