Ebstein's anomaly: an electrophysiological perspective.

Ebstein's anomaly of the tricuspid valve (EA) is an uncommon congenital cardiac malformation. It can present with atrioventricular tachycardia (AVRT), atrioventricular nodal re-entrant tachycardia (AVNRT), atrial arrhythmias, and rarely with ventricular tachycardia. The 12-lead electrocardiogram (ECG) is critically important and often diagnostic even prior to an electrophysiology study (EPS). Due to its complex anatomy, it poses particular challenges for mapping and ablation, even for an experienced electrophysiologist. In this review, we aim to provide insight into the electrophysiological perspective of EA and an in-depth analysis of the various arrhythmias encountered in diverse clinical scenarios.

Cardiac troponin in hospitalized COVID-19 patients: Incidence, predictors, and outcomes.

BACKGROUND: The incidence, predictors, and association of cardiac troponin with mortality in hospitalized COVID-19 were not adequately studied in the past and were also not reported from an Indian hospital. METHODS: In this retrospective cohort study, the cardiac troponin of 240 hospitalized COVID-19 patients was measured. The incidence, predictors, and association of elevated cardiac troponin with in-hospital mortality were determined among hospitalized COVID-19 patients. RESULTS: The cardiac troponin was elevated in 12.9% (31/240) of the patients. The troponin was elevated in the patients in the older age group (64 years vs. 55 years, p = .002), severe COVID-19 illness (SpO2 < 90%) (93.5% vs. 60.8%, p < .001), low arterial oxygen saturation (SpO2) (80% vs. 88%, p = .001), and low PaO2/FiO2 ratio (p < .0001). The patients with elevated cardiac troponin had elevated total leukocyte counts (TLC) (p = .001), liver enzyme (p = .025), serum creatinine (p = .011), N-terminal-Pro Brain natriuretic peptide (p < .0001), and d-dimer (p < .0001). The majority of the patients with elevated cardiac troponin were admitted to the intensive care unit (90.3% vs. 51.2%; p < .0001), were on a ventilator (61.3% vs. 21.5%; p < .0001), and had higher mortality (64.5% vs. 19.6%; p < .0001). The Kaplan-Meir survival analysis showed that the patients with elevated troponin had worse survival (p log-rank<.0001). Age, NT-ProBNP, d-dimer, and ventilator were the predictors of elevated troponin in multivariate logistic regression analysis. The Cox-regression analysis showed a significant association between elevated cardiac troponin and in-hospital mortality (adjusted hazard ratio 2.13; 95% confidence interval [CI] 1.145-3.97; p = .017). Two-thirds (65%) of patients with elevated cardiac troponin died during their hospital stay. CONCLUSIONS: COVID-19 patients with elevated cardiac troponin had severe COVID illness, were more commonly admitted to an intensive care unit, were on a ventilator, and had high in-hospital mortality.

Prevalence of arrhythmia in COVID-19 patients with mild/moderate and severe illness: a prospective cohort study.

OBJECTIVES: The type of arrhythmias, and their prevalence in mild/moderate and severe COVID-19 patients admitted to the hospital are unknown from a prospective cohort study. METHODS: We did continuous electrocardiograms along with multiple ECGs in 305 consecutive hospitalized COVID-19 patients. RESULTS: The incidence of arrhythmias was 6.8% (21/305) in the target population. The incidence of arrhythmias was 9.2% (17/185) in patients with severe COVID-19 illness and 3.3% (4/120) in patients with mild/moderate COVID-19 illness with no significant difference (p = 0.063). All the arrhythmias were new-onset arrhythmias in this study. 95% (20/21) of these arrhythmias were atrial arrhythmia with 71.42% (15/21) being atrial fibrillation and one episode of sustained polymorphic ventricular tachycardia. No episode of high-grade atrioventricular block, sustained monomorphic ventricular arrhythmia, or torsades de pointes arrhythmias were observed in this study. The patients with arrhythmias were admitted to the intensive care unit (80.9% vs. 50.7%; p: 0.007), were on a ventilator (47.6% vs. 21.4%; p: 0.006), and had high in-hospital mortality (57.1% vs. 21.1%; p: 0.0001) than patients without arrhythmias. CONCLUSION: Atrial arrhythmias were the most frequent arrhythmias in hospital-admitted COVID-19 patients with atrial fibrillation being the most common arrhythmia. TRIAL REGISTRATION: Clinical Trial Registry India (CTRI) (CTRI/2021/01/030788). (https://www.ctri.nic.in/).

Semantic segmentation in medical images through transfused convolution and transformer networks.

Recent decades have witnessed rapid development in the field of medical image segmentation. Deep learning-based fully convolution neural networks have played a significant role in the development of automated medical image segmentation models. Though immensely effective, such networks only take into account localized features and are unable to capitalize on the global context of medical image. In this paper, two deep learning based models have been proposed namely USegTransformer-P and USegTransformer-S. The proposed models capitalize upon local features and global features by amalgamating the transformer-based encoders and convolution-based encoders to segment medical images with high precision. Both the proposed models deliver promising results, performing better than the previous state of the art models in various segmentation tasks such as Brain tumor, Lung nodules, Skin lesion and Nuclei segmentation. The authors believe that the ability of USegTransformer-P and USegTransformer-S to perform segmentation with high precision could remarkably benefit medical practitioners and radiologists around the world.

A Case With Inferior Wall Myocardial Infarction and Conduction Abnormalities: Addressing the Diagnostic Challenges.

Conduction disturbances are an important complication of ST-elevation myocardial infarction (STEMI). Conduction disturbances such as fascicular blocks and bundle branch blocks are associated with alteration of QRS morphology and secondary ST-T wave changes that can influence the diagnosis of acute myocardial ischemia. We report an interesting case where a patient presented with inferior wall myocardial infarction (MI), right bundle branch block (RBBB), and left anterior hemiblock (LAHB). We discuss the challenges in diagnosing MI in such patients, including the impact of QRS changes in RBBB and LAHB, their influence on diagnosis of STEMI, and differentiation of combined first-degree AV block and bifascicular block from trifascicular block.

Railroad Pattern of Atrial Intervals in a Dual-chamber Pacemaker Patient-What Is the Mechanism and How to Manage?

A 55-year-old woman with a dual-chamber pacemaker presented with brief episodes of rapid palpitation. The device recorded several stored atrial high-rate and ventricular high-rate episodes. The atrial intervals showed an interesting railroad track pattern during a non-sustained episode of ventricular tachycardia. We discussed the differential diagnosis of railroad track patterns on the atrial channel. In our case, it was related to far-field R-wave oversensing.

Effect of Yoga on Clinical Outcomes and Quality of Life in Patients With Vasovagal Syncope (LIVE-Yoga).

OBJECTIVES: This study aims to determine the impact of yoga as an adjunct to standard therapy versus standard therapy alone on the symptomatic burden in patients with recurrent vasovagal syncope (VVS). BACKGROUND: There is a significant reduction in the quality of life (QoL) of patients with recurrent VVS. Existing management therapies have been largely ineffective. Recent trials have demonstrated the efficacy of yoga in diseases with autonomic imbalance, suggesting its possible utility in VVS. METHODS: Patients with recurrent VVS were randomized to receive either a specialized yoga training program in addition to current guideline-based therapy (intervention arm, group 1) or current guideline-based therapy alone (control arm, group 2). The primary outcome was a composite of the number of episodes of syncope and presyncope at 12 months. Secondary outcomes included QoL assessment by World Health Organization Quality of Life Brief Field questionnaire (WHOQoL-BREF) scores and Syncope Functional Status Questionnaire scores at 12 months, head up tilt test, and heart rate variability at 6 weeks. RESULTS: A total of 55 patients underwent randomization. The mean number of syncopal or presyncopal events at 12 months was 0.7 ± 0.7 in the intervention arm compared to 2.52 ± 1.93 in the control arm (P < 0.01). In the intervention arm, 13 (43.3%) patients remained free of events versus 4 (16.0%) patients in the control arm (P = 0.02). QoL at 12 months showed significant improvement of all Syncope Functional Status Questionnaire scores and 2 domains of WHOQoL-BREF scores (P < 0.05). CONCLUSIONS: Yoga as adjunctive therapy is superior to standard therapy alone in reducing the symptomatic burden and improving QoL in patients with recurrent VVS.

Incidence and Predictors of Implantable Cardioverter-defibrillator Therapies After Generator Replacement-A Pooled Analysis of 31,640 Patients' Data.

Among primary prevention implantable cardioverter-defibrillator (ICD) recipients, 75% do not experience any appropriate ICD therapies during their lifetime, and nearly 25% have improvements in their left ventricular ejection fraction (LVEF) during the lifespan of their first generator. The practice guidelines concerning this subgroup's clinical need for generator replacement (GR) remain unclear. We conducted a proportional meta-analysis to determine the incidence and predictors of ICD therapies after GR and compared this to the immediate and long-term complications. A systematic review of existing literature on ICD GR was performed. Selected studies were critically appraised using the Newcastle-Ottawa scale. Outcomes data were analyzed by random-effects modeling using R (R Foundation for Statistical Computing, Vienna, Austria), and covariate analyses were conducted using the restricted maximum likelihood function. A total of 31,640 patients across 20 studies were included in the meta-analysis with a median (range) follow-up of 2.9 (1.2-8.1) years. The incidences of total therapies, appropriate shocks, and anti-tachycardia pacing post-GR were approximately 8, 4, and 5 per 100 patient-years, respectively, corresponding to 22%, 12%, and 12% of patients of the total cohort, with a high level of heterogeneity across the studies. Greater anti-arrhythmic drug use and previous shocks were associated with ICD therapies post-GR. The all-cause mortality was approximately 6 per 100 patient-years, corresponding to 17% of the cohort. Diabetes mellitus, atrial fibrillation, ischemic cardiomyopathy, and the use of digoxin were predictors of all-cause mortality in the univariate analysis; however, none of these were found to be significant predictors in the multivariate analysis. The incidences of inappropriate shocks and other procedural complications were 2 and 2 per 100 patient-years, respectively, which corresponded to 6% and 4% of the entire cohort. Patients undergoing ICD GR continue to require therapy in a significant proportion of cases without any correlation with an improvement in LVEF. Further prospective studies are necessary to risk-stratify ICD patients undergoing GR.

Intramural Hematoma Burrowing Behind a Coronary Stent: Optical Coherence Tomography Findings.

A 47-year-old patient underwent elective percutaneous coronary intervention for two separate lesions in left circumflex artery with a intervening normal segment. After completion of the procedure, there was abrupt vessel closure in the intervening normal segment. Intracoronary imaging using optical coherence tomography (OCT) demonstrated a large intramural hematoma (IMH) extending distally behind the stent. We describe the OCT findings of IMH using cross-sectional, longitudinal and stent-rendered images, and discuss its management.