The predictive value of electrocardiographic polarization parameters on appropriate ICD shock in primary prevention heart failure patients.

OBJECT: The effect of frontal QRS-T angle, Tp-e and Tp-e/QT ratio on cardiac events have been shown in many studies. In this study, we aimed to determine the prognostic value of frontal QRS-T angle, TPe and Tp-e/QT ratio on ICD shock in patients who had ICD (Implantable Cardioverter Defibrillator) implanted due to heart failure with reduced ejection fraction (HFrEF). MATERIAL AND METHOD: 158 patients with HFrEF who had previous ICD implantation were retrospectively analyzed. 27 patients were found to have an appropriate shock. Frontal QRS-T angle, Tp-e interval, Tp-e/QT ratio were calculated by evaluating the basal ECG records of the patients. Comparisons of these arrhythmogenic predictors were made in patients with and without ICD shock at follow-up. RESULT: When 158 patients with previous ICD implantation were analyzed in two groups with and without ICD shock, the number of patients with frontal QRS-T angle >120°, Tp-e interval > 105 ms, Tp-e/QT > 0.2 in the shock group (n: 27) was found to be high with a different significance (p:<0.01, p:<0.01, p:<0.01). There was no significant difference between the two groups regarding other ECG parameters such as QRS duration, QT interval, PR interval, fragmented QRS and positive T wave. In addition, more amiodarone use was observed in the shock group, and more hyperlipidemia cases were observed in the non-shocked group (p:0.01; p:<0.01). CONCLUSION: Increased frontal QRS-T angle, Tp-e interval, and Tp-e/QT ratio are arrhythmogenic parameters and predict appropriate ICD shock.

Evaluation of left atrial and left ventricular functions in patients with Wolff-Parkinson-White syndrome before and after radiofrequency catheter ablation using three-dimensional speckle tracking echocardiography.

BACKGROUND: Wolff-Parkinson-White (WPW) syndrome is one of the most common congenital cardiac abnormalities among ventricular pre-excitation syndromes. Radiofrequency catheter ablation (RFCA) treatment of accessory pathways (APs) in WPW patients is an established curative therapy restoring normal atrioventricular conduction. We have not encountered any studies evaluating both the LA and LV functions of these patients before and after RFCA with three dimensional-speckle tracking echocardiography (3D-speckle tracking echocardiography (STE)). AIM: The purpose of the current study was to assess the LA and LV functions in patients with WPW syndrome before and after RFCA using 3D-STE. METHODS: A total of 21 patients with WPW syndrome who had been scheduled for RFCA were prospectively recruited for this study. 3D-STE examinations of the patients were performed 12-24 h before ablation and 1 month after ablation. RESULTS: The LV-global longitudinal strain (LV-GLS) and LV-global circumferential strain (LV-GCS) were significantly depressed in the pre-RFCA WPW group than in the control group (-14.3 ± 2.1 vs. -21.5 ± 2.2, p < .001; -12.6 ± 1.8 vs. -20.4 ± 1.8, p < .001, respectively). The left atrial strain-reservoir (LAS-r) and LAS-active were significantly decreased in the pre-RFCA WPW group than in the control group (31.9 ± 2.4 vs. 48.8 ± 2.6, p < .001; 11.7 ± 2 vs. 26.5 ± 2.1, p < .001, respectively). The LV-GLS, LV-GCS, LAS-r, and LAS-active values improved after RFCA compared to before. CONCLUSION: The results of our study indicated that there are subclinical impairments in LV and LA myocardial dynamics in the apparently healthy WPW patients, and these deteriorations improve after RFCA of AP.

An Effective Novel Index for Predicting the Recurrence of Atrial Fibrillation Ablation: P Wave Duration-to-Amplitude Ratio.

OBJECTIVE: Atrial fibrillation is the most common arrhythmia observed in the clinical practice. Pulmonary vein isolation is a well established treatment option for atrial fibrillation but is limited by recurrence. Previous studies have demonstrated that abnormal P wave indices were associated with adverse atrial remodeling and its role in predicting atrial fibrillation recurrence. In the present study, we aimed to evaluate the place of a novel index as we named P wave duration-to-amplitude ratio in predicting the recurrence of atrial fibrillation. METHODS: Patients who underwent pulmonary vein isolation for symptomatic drug-resistant atrial fibrillation between January 2016 and March 2018 were retrospectively screened. A total of 111 patients were enrolled in the current study. P wave indices of the patients were calculated by precisely measuring the electrocardiogram traces recorded with an electrophysiology recording system. RESULTS: While P wave duration (129 ± 18.4 vs. 109 ± 15.7 ms, P <.001), P wave duration-toamplitude ratio (1072.7 ± 528.3 vs. 626.9 ± 368 ms/mV, P <.001), P wave peak time (65 ± 12 vs. 54 ± 10 ms, P <.001), and P wave dispersion (49 ± 14.1 vs. 27.9 ± 17 ms, P =.001) values were significantly higher in the atrial fibrillation recurrence (+) group, the P wave amplitude (0.12 ± 0.05 vs. 0.18 ± 0.02 mV, P <.001) value was found to be lower. A P wave duration-t o-amplitude ratiovalue of >830 ms/mV has 61.8% sensitivity and 88.4% specificity for the prediction of the atrial fibrillation recurrence (area of under the curve [AUC], 0.727). CONCLUSION: P wave duration-to-amplitude ratio, which may be considered as an indicator of the temporal and electrical propagation of the P wave in the atria, can predict atrial fibrillation ablation recurrence.

Comparison of electrophysiological characteristics of right- and left-sided Mahaim-type accessory pathways.

AIMS: Mahaim-type accessory pathways (MAPs) are generally right-sided due to the embryological differentiation, but left-sided localization is also possible. This study aims to compare the clinical and electrophysiological characteristics of right- and left-sided MAPs. METHODS: Of 251 patients diagnosed with AP by electrophysiological study between November 2015 and February 2020, 12 patients with MAP were included (right sided n = 8, left sided n = 4). MAP was diagnosed if; (1) no retrograde conduction; (2) anterograde decremental conduction; (3) adenosine sensitivity; and (4) Mahaim potential at successful ablation site were present. RESULTS: Ten of twelve MAPs were clustered on the lateral walls of the mitral (n = 3, 75%) and tricuspid annuli (n = 7, 87.5%). Right-sided MAPs were mostly long pathways extending toward the conduction system whereas left-sided MAPs were short extending toward the neighboring myocardium. For right- and left-sided APs, the median QRS times were 129 and 156 ms (p = .042), the median VAbl -RVApex intervals were -12 and 64 ms (p = .007), the median QRS-V(His) intervals were 16 and 86 ms (p = .120), and the median VAbl -QRS interval was -8 and 12 ms (p = .017), respectively. Coexistence of dual atrioventricular node physiology was observed only in right-sided APs (n = 3, 37.5%). CONCLUSION: MAPs are more typically located on the right but may rarely be seen on the left. Catheter ablation was associated with high success without complications.