Negativity of the electromechanical window: relation to frequent premature ventricular complexes

OBJECTIVE: The electrome-chanical window (EMW) was investigated as a new predictor of arrhythmia in the presence of long QT. However, the use of EMW to predict id-iopathic frequent ventricular premature com-plexes (PVCs) in those with normal QT intervals has not been clarified.PATIENTS AND METHODS: This single -cen-ter study included consecutive patients who presented to the Cardiology Clinic with palpita-tions and were found to have idiopathic PVC on 24-hour Holter monitoring. Those with a PVC/24-hour frequency of < 1% were defined as group 1, 1-10% as group 2, and > 10% as group 3. The EMW was defined as the time difference (in ms) between the aortic valve closure and the end of the QT interval, measured from an ECG on the concurrent echocardiogram.RESULTS: A total of 148 patients were includ-ed in the study, 64% (n = 94) of which were fe-male. The patients' mean age was 50.11 +/- 14.7. The groups were similar in terms of the patients' age, BMI, and comorbidities. There was a statis-tically significant difference between the three groups in terms of the EMW measurements (group 1: 3.78 +/- 19.6, group 2:-7 +/- 30.9, group 3:-34.83 +/- 55.2 ms: p < 0.001). In the multivar-iate regression analysis, the EMW (OR 0.971, p = 0.007) and every 10-ms decrease in the EMW (OR 1.254, p = 0.011) were thus determined to be independent predictors of PVC > 10%. An EMW value of <=-15 ms was associated with the fre-quency of 24-h PVC > 10%, with a sensitivity of 70% and a specificity of 70% (AUC 0.716, 95% CI: 0.636-0.787 p < 0.001).CONCLUSIONS: The results showed that a negative increase in the EMW may be associat-ed with frequent idiopathic PVCs.