The correlation between the length of QTc interval, ventricular ectopic activity and ultrasonically determined impairment of the LV wall motion in acute myocardial infarction

The aim of the study was to determine: – whether in patients with acute myocardial infarction (AMI) the duration of the QTc interval correlates with the echocardiographically determined left ventricular wall motion abnormality score (WMSI), – whether patients with AMI show a correlation between the duration of the QTc interval and frequency and complexity of ventricular ectopic activity, – whether there is a correlation between the WMSI and the incidence and complexity of ventricular arrhythmias. In a series of 40 consecutive patients with a 4-day history of AMI, left ventricular WMSI and QTc intervals in ECG leads corresponding to the site of AMI, were determined. 24-hour ECGs were recorded and graded according to Lown. A statistically significant positive correlation was found between the WMSI and the QTc interval duration (r = 0,75; p < 0,001), especially in patients with anterior AMI (r = 0,94; p < 0,001). The WMSI was higher in patients with high-degree (Lown 3-5) ventricular ectopic activity (p < 0,05). There was no significant correlation between the duration of the QTc interval and the complexity of ventricular ectopic activity.