Arrhythmia constitutes a problem with the rate or rhythm of the heartbeat, and an early diagnosis is essential for the timely inception of successful treatment. We have jointly optimized the entire multi-stage arrhythmia classification scheme based on 12-lead surface ECGs that attains the accuracy performance level of professional cardiologists. The new approach is comprised of a three-step noise reduction stage, a novel feature extraction method and an optimal classification model with finely tuned hyperparameters. We carried out an exhaustive study comparing thousands of competing classification algorithms that were trained on our proprietary, large and expertly labeled dataset consisting of 12-lead ECGs from 40,258 patients with four arrhythmia classes: atrial fibrillation, general supraventricular tachycardia, sinus bradycardia and sinus rhythm including sinus irregularity rhythm. Our results show that the optimal approach consisted of Low Band Pass filter, Robust LOESS, Non Local Means smoothing, a proprietary feature extraction method based on percentiles of the empirical distribution of ratios of interval lengths and magnitudes of peaks and valleys, and Extreme Gradient Boosting Tree classifier, achieved an F 1 -Score of 0.988 on patients without additional cardiac conditions. The same noise reduction and feature extraction methods combined with Gradient Boosting Tree classifier achieved an F 1 -Score of 0.97 on patients with additional cardiac conditions. Our method achieved the highest classification accuracy (average 10-fold cross-validation F 1 -Score of 0.992) using an external validation data, MIT-BIH arrhythmia database. The proposed optimal multi-stage arrhythmia classification approach can dramatically benefit automatic ECG data analysis by providing cardiologist level accuracy and robust compatibility with various ECG data sources.ECGs represent the filtered electrical activity generated by the heart. An ECG from lead II presents a normal heartbeat under sinus rhythm that has a characteristic shape with three features, a P-wave presenting the atrial depolarization process, a QRS complex denoting the ventricular depolarization process, and a T-wave representing the ventricular repolarization. The normal feature sequence of the cardiac cycle is P-wave, QRS complex, and T-wave with sections between them called segments. Three such major segments are the PR, ST, and TP segments. Important periods within and between ECG waves are the PR, QT, and RR intervals.Damage to the heart muscle or nerves can change the electrical activity of the heart and induce a corresponding change in the shape of the ECGs. Thus, ECG is a major clinical diagnostic tool for various heart abnormalities. Arrhythmias are a family of conditions characterized by aberrations from the normal rate or rhythm of the heartbeats. There are several dozen classes of arrhythmia with various distinct manifestations, excessively slow or fast heartbeats such as sinus bradycardia and atrial tachycardia, irregular rhythm with missing or distorte...

Despite advances in surgery, imaging, chemotherapy, and radiotherapy, the poor overall cancer-related death rate remains unacceptable. Novel therapeutic strategies are desperately needed. Nowadays, targeted therapy has become the most promising therapy and a welcome asset to the cancer therapeutic arena. There is a large body of evidence demonstrating that the Notch signaling pathway is critically involved in the pathobiology of a variety of malignancies. In this review, we provide an overview of emerging data, highlight the mechanism of the Notch signaling pathway in the development of a wide range of cancers, and summarize recent progress in therapeutic targeting of the Notch signaling pathway.

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Introduction A left common pulmonary vein (LCPV) is a common anatomical variant in atrial fibrillation (AF) patients. Whether an LCPV influences outcomes of repeated radiofrequency catheter ablation (RFCA) for AF has not been elucidated. Methods From a prospectively collected database, we enrolled 154 patients who received repeated RFCA for recurrent AF after the initial RFCA (56 ± 9 years, 72% paroxysmal AF, 32 patients with an LCPV, and 122 patients with typical left‐sided pulmonary veins [PVs]). Median postprocedural follow‐up was 26 months. The primary outcome was an episode of AF, atrial tachyarrhythmia, or atrial flutter lasting for more than 30 seconds, after the 3 months blanking period following the repeated procedure. Results After the follow‐up period, 75 patients suffered recurrence after repeated ablation. In the Kaplan‐Meier analysis, an LCPV was significantly associated with less recurrence (hazard ratio [HR]: 0.39; 95% confidence interval [CI]: 0.28‐0.79; P = 0.005). In subgroup analysis, the significant association persisted in paroxysmal AF patients. Regarding persistent AF patients, an LCPV tended to be associated with less recurrence with no statistical significance (HR: 0.40; 95% CI: 0.20‐1.03; P = 0.067). In multivariate analyses, an LCPV still independently predicted freedom from recurrence (HR: 0.44; 95% CI: 0.22‐0.88; P = 0.02). Conclusion Compared with typical left‐sided PVs, an LCPV was independently associated with better outcomes after repeated RFCA of AF, particularly in patients with paroxysmal AF.