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Competing Interests: Disclosures The authors have no conflicts of interest to disclose.

Background: Heart failure (HF) is associated with considerable mortality. The electrocardiographic frontal QRS-T angle is a simple parameter to measure, reflects changes in the direction of the repolarization sequence and predicts outcome in patients with HF. Data regarding temporal changes in the frontal QRS-T angle in patients with HF and its impact on outcome is limited., Aim: To evaluate temporal changes in the frontal QRS-T angle and its effect on survival in patients with HF., Methods: Baseline and follow-up QRS-T angle were calculated from the frontal QRS and T axis of the 12-lead surface electrocardiogram. Patients were followed for survival., Results: 2,929 HF patients were evaluated. Median interval between baseline ECG and follow-up ECG was 895 days, median follow-up time was 1526 days. Overall, the QRS-T angle tended to be stable, with minor changes in the angle over time. The median QRS-T angle change was +3° (IQR -19° to +30°). Overall survival during follow-up was 60%. Cox regression analysis after adjustment for significant predictors demonstrated that the QRS-T angle was an incremental predictor of increased mortality. A widening of the QRS-T angle during follow-up was independently associated with an increase in mortality, evident with an increase of the QRS-T angle difference above 0° (P<0.0001 for the adjusted model)., Conclusion: QRS-T angle is relatively stable in patients with HF and is a powerful predictor of outcome. Widening of the QRS-T angle has predictive value and is an ominous sign.

Background: Acute myocarditis carries a variable prognosis. We evaluated the morbidity and mortality rates in patients with acute myocarditis and admission electrocardiographic predictors of outcome., Methods and Results: Patients admitted to a tertiary hospital with a clinical diagnosis of acute myocarditis were evaluated; 193 patients were included. Median follow-up was 5.7 years, 82% were male, and overal median age was 30 years (range 21-39). The most common clinical presentations were chest pain (77%) and fever (53%). The 30-day survival rate was 98.9%. Overall survival during follow-up was 94.3%. The most common abnormalities observed on electrocardiography were T-wave changes (36%) and ST-segment changes (32%). Less frequent changes included abnormal T-wave axis (>105° or < -15°; 16%), abnormal QRS axis (12%), QTc >460 ms (11%), and QRS interval ≥120 ms (5%). Wide QRS-T angle (≥100°) was demonstrated in 13% of the patients and was associated with an increased mortality rate compared with patients with a narrow QRS-T angle (20% vs 4%; P = .007). The rate of heart failure among patients with a wide QRS-T angle was significantly higher (36% vs 10%; P = .001). Cox regression analysis demonstrated that a wide QRS-T angle (≥100°) was a significant independent predictor of heart failure (hazard ratio [HR] 3.20, 95% confidence interval [CI] 1.35-7.59; P < .01) and of the combined end point of death or heart failure (HR 2.56, 95% CI 1.14-5.75; P < .05)., Conclusions: QRS-T angle is a predictor of increased morbidity and mortality in acute myocarditis., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Ventricular safety pacing (VSP) is used to avoid cross talk by delivering ventricular stimulus shortly after an atrial-paced event if ventricular-sensed event occurs. Although VSP is a protective feature that exists for decades in different pacing devices, there are some reports of unfavorable outcomes of this algorithm. More so, health care providers sometimes face difficulties in interpreting and dealing with VSP strips. This case report discusses an important pacemaker algorithm and encourages further attention to possible pitfalls and hence avoids unnecessary interventions. [ABSTRACT FROM AUTHOR]