Study of Rhythm Disturbances in Patients with Acute Myocardial Infarction in Government Royapettah Hospital

INTRODUCTION: Despite impressive strides in diagnosis and management of acute myocardial infarction in the past three decades, acute myocardial infarction continues to be a major health problem. Projection from World Health Federation is that the burden of ischaemic heart disease in the developing countries will become similar to that of developed countries. About 50% of death from acute myocardial infarction occur within 1hr of the event and are attributable to arrhythmias most often ventricular fibrillation. Ischaemic injury can produce conduction blocks at any level of the atrioventricular or Intraventricular conduction systems. Such conduction block can occur in the atrioventricular node producing various grades of AV block. Conduction block can occur in either main bundle branch producing right or left bundle branch block or in the anterior and posterior fascicle of left bundle branch, producing left anterior &left posterior fascicular blocks respectively. AIM OF THE STUDY: 1. To study the incidence of rhythm disturbances in acute myocardial infarction. 2. To evaluate the age, sex distribution & various other risk factors in relation to rhythm disturbances occurring in acute myocardial infarction. 3. To correlate between the different types of rhythm disturbances in relation to the location & type of acute myocardial infarction. 4. To evaluate the incidence of rhythm disturbances in thrombolysed & non thrombolysed patients. MATERIALS AND METHODS: The study was conducted in Government Royapettah Hospital during the period from January 2006 to may 2006. The patients admitted to ICCU were taken up for study. A detailed history physical examination &laboratory work up was done in all patients. Total No of Patients: 100, Age Group: 20 to 90, Clinical presentation, Enzyme levels, ECG findings, Echocardiography findings, were taken into account. Criteria for Entry to Study Population: 1. History of chest pain lasting more than 30 minutes not relieved by nitrates or rest. 2. Typical ECG changes of acute myocardial infarction Exclusion Criteria: All patients with evidence of preexisting rhythm disturbances were excluded from the study. Variable Recorded at Admission: ECG were taken in all patients. ECG recording were done immediately after admission, if thrombolysed one hour later, once daily for 7 days, whenever complications occurred & at discharge. Special right precordial leads V3R V4R V5R were taken in patients with inferior wall MI & also posterior leads were taken in suspected cases of posterior wall MI. Long strips in L II, V I were taken to study the rhythm disturbances. OBSERVATION: 100 Patients of acute myocardial infarction were included in this study. They consisted of 77 male and 23 female patients. The youngest patient was a 23 year old male and the oldest patient was a 84 year old male. CONCLUSION: In this dissertation entitled the “Study of Rhythm Disturbances in Patients with Acute Myocardial Infarction in Government Royapettah Hospital”. 100 patients with acute myocardial infarction were studied with reference to clinical presentation, risk factors, ECG findings, and echocardiographic finding and observed rhythm disturbances were correlated and following conclusions were derived: 1. The incidence of rhythm disturbances in acute myocardial infarction is 46%. 2. The distribution of rhythm disturbances are almost equal in males and females ( p value 0.3365). 3. Rhythm disturbances were more common in the age group 50-59. 4. The incidence of rhythm disturbances in patients with Diabetes mellitus and hypertension is high. (p value 0.0000). 5. The incidence of rhythm disturbances in patients who smoke is high. (p value 0.0000). 6. The incidence of rhythm disturbances in patients who consume alcohol is high. (p value 0.0000). 7. Atrioventricular blocks are more common in inferior wall myocardial infarction. (p value 0.0507). 8. Ventricular ectopics, ventricular tachycardia, ventricular fibrillation, atrial fibrillation are more common in anterior wall myocardial infarction. 9. Most of the Intraventricular conduction block occurred in patients with anterior wall myocardial infarction. 10. Right bundle branch block is the most common Intraventricular conduction abnormality noted with an incidence of 10. 11. The incidence of rhythm disturbances in non thrombolysed patients is more (29%) compared to thrombolysed patients 17% (p value 0.00545). 12. The incidence of death is increased among patients with rhythm disturbances (p value 0.00853)