Abstract 13067: When Are 3 ECG Leads Better Than 12? Streamlining and Optimizing ECG Assessment in Sudden Death Prediction
Introduction: Prolonged Tpeak to Tend (Tp-e) interval, an index of repolarization on the 12-lead ECG, is associated with increased risk for sudden cardiac death. However, there is no current consensus on which of the 12 leads is the most sensitive to measure the longest Tp-e interval. Aim: The aim of this study was to measure all 12 ECG leads and to analyze whether there are leads that are most sensitive to detect prolongation of Tp-e in order to optimize methodology for future investigations. Methods: Fifteen healthy volunteers (F/M 6/9; mean age 25 yrs) were included in our study. We recorded the 12-lead ECG for 5-minutes. Tp-e was defined as the interval from the peak of the T wave to the end of the T wave. QT is the interval from QRS complex onset to the end of the T wave. Using commercially available software (AdInstruments), three primary outcomes, Tp-e interval, Tp-e/QT, Tp-e/QTc ratios, and two secondary outcomes, QT, QTc intervals, were determined. Results: The location of maximum value for primary outcomes (Tp-e, Tp-e/QT, Tp-e/QTc) were not evenly distributed across the 12 leads, but most frequently was located in leads V2, V3 & V4. The maximum Tp-e was located in one of these three leads 79.7% of the time (CI 69.4, 89.9%) vs other leads (p=0.007, Figure). Conversely, maximum values for the secondary outcomes (QT, QTc) were located in AVL, AVR and III (Figure). Two of the leads, V5 and V6, never had a maximum value for any outcomes. Conclusion: Preliminary findings in our study suggest that investigators should focus on leads V2, V3 & V4 to detect prolongation of Tp-e intervals and leads AVL, AVR & III for prolongation of QT interval when investigating associations with sudden cardiac death.