Value of electrocardiography in localization of the occlusion site in left anterior descending coronary artery in acute anterior myocardial infarction

This study was conducted to evaluate the electocardiographic localization of the occlusion site in left anterior descending coronary artery in acute anterior myocardial infarction. This study involved 50 patients presenting with acute anterior myocardial infarction with st segment elevation>2mm in two consecutive leads [vl-v3]. All patients underwent thorough history taking, full clinical examination, laboratory work up involving cardiac markers, serial ECGs and coronary angiography within 8 days. ECG changes were correlated with the angiographic site of LAD occlusion whether proximal to1[st] diagonal or distal to 1[st] diagonal. The culprit lesion was proximal to 1[st] diagonal in 27[54%] patients, distal to 1[st] diagonal in 21[42%] patients, and both proximal and distal to 1[st] diagonal in 2 patients who were excluded from the study. ECG predictors of LAD occlusion proximal to D1 were ST elevation in aur, ST depression in inferior leads, ST depression in V5, ST elevation in V1>2.5mm. While ECG predictors of LAD occlusion distal to Dl were absence of ST depression in inferior leads. ST depression avl, Q in V4-V5. In acute anterior myocardial infarction electrocardiogram is useful to predict the left anterior descending occlusion site

Prevalence and determinants of late potentials in patients with unstable angina

To study the factors determining the positivety of late potentials and its prevalence in unstable angina, fifty unstable angina patients together with a sex and age matched twenty stable angina patients serving as control were included in this study. All were subjected to careful history taking and clinical examination, laboratory blood analysis; twelve leads resting surface ECG; echo-Doppler study; 24-hours Holterniortitoring and signal averaged ECG [SAECG] namely filtered QRS complex duration, root of the mean square of signal amplitude in the last 40 msec of the filtered QRS and the duration of terminal filtered low signal amplitude [LAS] with frequency amplitude<40 uv. Echo-Doppler; Holter monitoring and SAECG were repeated two weeks later for the unstable angina patients. Exercise treadmill was done to confirm the diagnosis of stable angina patients. In the present study the incidence of positive LPs was 24% on admission and was significantly reduced to 14% after 2 weeks of medical therapy in unstable angina patients. However, non of the stable angina patients had positive LPs. All the parameters of SAECG were significantly higher in the unstable angina patients. Sex and age had no effect on the incidence of LPs, inferior ischemia had significantly higher positive LPs than anterior ischemia [55% vs 33%/. Holter-reported ischaemic episodes and echo-reported regional wall motion abnormalities were significantly positively correlated with positive LPs. The presence of left ventricular systolic and diastolic dysfunction significantly increase the incidence of positive LPs and their improvement significantly reduce the incidence of positive LPs Positive LPs was recorded in 24% of patients with unstable angina Left ventricular systolic and diastolic dysfunction and the frequency of ischaemic episodes showed significant positive correlation with the incidence of positive LPs Medical therapy significantly reduced the incidence of positive LPs