The emergence and destiny of automated methods to differentiate wide QRS complex tachycardias.

Accurate differentiation of wide complex tachycardias (WCTs) into ventricular tachycardia (VT) or supraventricular wide complex tachycardia (SWCT) using non-invasive methods such as 12­lead electrocardiogram (ECG) interpretation is crucial in clinical practice. Recent studies have demonstrated the potential for automated approaches utilizing computerized ECG interpretation software to achieve accurate WCT differentiation. In this review, we provide a comprehensive analysis of contemporary automated methods for VT and SWCT differentiation. Our objectives include: (i) presenting a general overview of the emergence of automated WCT differentiation methods, (ii) examining the role of machine learning techniques in automated WCT differentiation, (iii) reviewing the electrophysiology concepts leveraged existing automated algorithms, (iv) discussing recently developed automated WCT differentiation solutions, and (v) considering future directions that will enable the successful integration of automated methods into computerized ECG interpretation platforms.

Glucagon-like peptide 1 (GLP-1) receptor agonists as a protective factor for incident depression in patients with diabetes mellitus: A systematic review.

Glucagon-like peptide 1 (GLP-1) receptor agonists are widely used for glycemic control in patients with diabetes mellitus (DM) and are primarily indicated for type 2 diabetes mellitus (T2DM). GLP-1 receptor agonists have also been shown to have neuroprotective and antidepressant properties. Replicated evidence suggests that individuals with DM are significantly more likely to develop depression. Herein, we aim to investigate whether GLP-1 receptor agonists can be used prophylactically on patients with DM to lower the risk of incident depression. We conducted a systematic search for English-language articles published on the PubMed/MEDLINE, Scopus, Embase, APA, PsycInfo, Ovid and Google Scholar databases from inception to June 6, 2022. Four retrospective observational studies were identified that evaluated the neuroprotective effects of GLP-1 receptor agonists on incident depression in patients with DM. We found mixed results with regards to lowering the risk of incident depression, with two studies demonstrating a significant reduction in risk and two studies showing no such effect. A single study found that dulaglutide may lower susceptibility to depression. Our results were limited by high interstudy heterogeneity, paucity of literature, and lack of controlled trials. While we did not find evidence of GLP-1 receptor agonists significantly lowering risk of incident depression in patients with DM, promising neuroprotective data presented in two of the included papers, specifically on dulaglutide where information is scarce, provide the impetus for further investigation. Future research should focus on better elucidating the neuroprotective potential of different classes and doses of GLP-1 receptor agonists using controlled trials.

Computerized electrocardiogram data transformation enables effective algorithmic differentiation of wide QRS complex tachycardias.

BACKGROUND: Accurate automated wide QRS complex tachycardia (WCT) differentiation into ventricular tachycardia (VT) and supraventricular wide complex tachycardia (SWCT) can be accomplished using calculations derived from computerized electrocardiogram (ECG) data of paired WCT and baseline ECGs. OBJECTIVE: Develop and trial novel WCT differentiation approaches for patients with and without a corresponding baseline ECG. METHODS: We developed and trialed WCT differentiation models comprised of novel and previously described parameters derived from WCT and baseline ECG data. In Part 1, a derivation cohort was used to evaluate five different classification models: logistic regression (LR), artificial neural network (ANN), Random Forests [RF], support vector machine (SVM), and ensemble learning (EL). In Part 2, a separate validation cohort was used to prospectively evaluate the performance of two LR models using parameters generated from the WCT ECG alone (Solo Model) and paired WCT and baseline ECGs (Paired Model). RESULTS: Of the 421 patients of the derivation cohort (Part 1), a favorable area under the receiver operating characteristic curve (AUC) by all modeling subtypes: LR (0.96), ANN (0.96), RF (0.96), SVM (0.96), and EL (0.97). Of the 235 patients of the validation cohort (Part 2), the Solo Model and Paired Model achieved a favorable AUC for 103 patients with (Solo Model 0.87; Paired Model 0.95) and 132 patients without (Solo Model 0.84; Paired Model 0.95) a corroborating electrophysiology procedure or intracardiac device recording. CONCLUSION: Accurate WCT differentiation may be accomplished using computerized data of (i) the WCT ECG alone and (ii) paired WCT and baseline ECGs.

Idiopathic Ventricular Fibrillation in a Previously Healthy Recreational Athlete.

There are several clinical challenges in the survivor of sudden cardiac arrest (SCA), including ensuring that a comprehensive diagnostic evaluation has been performed and providing counseling on return to activity. We report a case of a highly conditioned athlete who presented following aborted SCA during exercise with a diagnosis of idiopathic ventricular fibrillation arrest. (Level of Difficulty: Intermediate.).

Automatic wide complex tachycardia differentiation using mathematically synthesized vectorcardiogram signals.

BACKGROUND: Automated wide complex tachycardia (WCT) differentiation into ventricular tachycardia (VT) and supraventricular wide complex tachycardia (SWCT) may be accomplished using novel calculations that quantify the extent of mean electrical vector changes between the WCT and baseline electrocardiogram (ECG). At present, it is unknown whether quantifying mean electrical vector changes within three orthogonal vectorcardiogram (VCG) leads (X, Y, and Z leads) can improve automated VT and SWCT classification. METHODS: A derivation cohort of paired WCT and baseline ECGs was used to derive five logistic regression models: (i) one novel WCT differentiation model (i.e., VCG Model), (ii) three previously developed WCT differentiation models (i.e., WCT Formula, VT Prediction Model, and WCT Formula II), and (iii) one "all-inclusive" model (i.e., Hybrid Model). A separate validation cohort of paired WCT and baseline ECGs was used to trial and compare each model's performance. RESULTS: The VCG Model, composed of WCT QRS duration, baseline QRS duration, absolute change in QRS duration, X-lead QRS amplitude change, Y-lead QRS amplitude change, and Z-lead QRS amplitude change, demonstrated effective WCT differentiation (area under the curve [AUC] 0.94) for the derivation cohort. For the validation cohort, the diagnostic performance of the VCG Model (AUC 0.94) was similar to that achieved by the WCT Formula (AUC 0.95), VT Prediction Model (AUC 0.91), WCT Formula II (AUC 0.94), and Hybrid Model (AUC 0.95). CONCLUSION: Custom calculations derived from mathematically synthesized VCG signals may be used to formulate an effective means to differentiate WCTs automatically.

The effects of antidepressant medications on antiretroviral treatment adherence in HIV-positive individuals with depression.

Background Extant literature has identified Major Depressive Disorder (MDD) as a comorbid disorder in individuals with seropositive human immunodeficiency disorder (HIV), and this may affect HIV-treatment efficacy. However, there is a paucity of literature evaluating the effects of antidepressant use on antiretroviral therapies (ART) in HIV-positive individuals. Herein, the following review assesses the effects of antidepressant medications on ART adherence in HIV-positive individuals with diagnosed MDD. Methods A systematic search on PubMed, Scopus, Web of Science, and Google Scholar search engines were conducted between database inception to June 12th, 2020 using the search and MeSH terms: (HIV) AND (antiretroviral or treatment) AND (depress*) AND (antidepressants) AND (adherence). Results We identified nine articles that evaluated ART adherence in HIV-positive individuals using antidepressants. Of the nine included articles, eight articles evaluated participants undergoing ART, and one article evaluated participants undergoing highly active antiretroviral therapy (HAART). Our primary findings suggest that patients who took antidepressant treatment for depression demonstrated greater adherence to HIV treatments and a reduction in missed HIV medication dosage. Limitations The heterogeneity of study design between the included studies was high. Conclusion The current review suggests that response to antidepressant medication may improve adherence to HIV treatments in HIV-positive individuals with comorbid depression. Further studies should expand the findings to explore the effects of disparate psychotropic agents on adherence behaviors among patients with HIV to identify the benefits of these agents on long-term health outcomes in this vulnerable clinical population.

The impact of overweight/obesity on monetary reward processing: A systematic review.

OBJECTIVE: Converging evidence suggests abnormalities in monetary reward processing may underlie the shared pathophysiology between major depressive disorder and obesity. As such, there is a need to parse deficits in specific subcomponents of monetary reward functioning (i.e., valuation, learning and anticipation). METHODS: PsycINFO, Google Scholar and PubMed databases were searched for English-language articles published between database inception to June 6th, 2020. Studies were identified using the following medical search heading (MeSH) terms and search strings: (reward (valuation OR motivation OR anticipation OR learning OR functioning OR decision-making OR reinforcement)) AND ((obesity OR overweight OR obese). RESULTS: Findings were reviewed from 11 studies evaluating the association between obesity and monetary reward processing. Four studies found significant differences in reward learning in individuals with obesity compared to normal-weight participants. Five studies found body mass index (BMI) to be predictive of willingness to expend effort (i.e., valuation) for a monetary reward. Three studies found changes in neural activations in the ventral striatum during anticipatory phases preceding receipt of a monetary reward in participants with obesity. CONCLUSIONS: Participants with obesity demonstrated significantly poorer performance in task-based measures of reward learning, valuation, and anticipation, resulting in lower monetary reward outcomes across all studies compared to healthy controls. Notably, participants with obesity and comorbid depression performed worse than participants with no comorbid depression. LIMITATIONS: There persists heterogeneity between studies with regards to inclusion of mood disorder populations and exclusion of psychiatric comorbidities in groups with obesity.

The WCT Formula II: An effective means to automatically differentiate wide complex tachycardias.

BACKGROUND: Differentiation of wide complex tachycardias (WCTs) into ventricular tachycardia (VT) or supraventricular wide complex tachycardia (SWCT) using conventional manually-operated electrocardiogram (ECG) interpretation methods is difficult. Recent research has shown that accurate WCT differentiation may be accomplished by automated approaches (e.g., WCT Formula) implemented by computerized ECG interpretation software. OBJECTIVE: We sought to develop a new automated means to differentiate WCTs. METHODS: First, a derivation cohort of paired WCT and baseline ECGs was examined to secure independent VT predictors to be incorporated into a logistic regression model (i.e., WCT Formula II). Second, the WCT Formula II was trialed against a separate validation cohort of paired WCT and baseline ECGs. RESULTS: The derivation cohort comprised 317 paired WCT (157 VT, 160 SWCT) and baseline ECGs. The WCT Formula II was composed of baseline QRS duration (p = 0.02), WCT QRS duration (p < 0.001), frontal percent time-voltage area change (p < 0.001), and horizontal percent time-voltage area change (p < 0.001). The area under the curve (AUC) for VT and SWCT differentiation was 0.96 (95% CI 0.94-0.98) for the derivation cohort. The validation cohort consisted of 284 paired WCT (116 VT, 168 SWCT) and baseline ECGs. WCT Formula II implementation on the validation cohort yielded effective WCT differentiation (AUC 0.96; 95% CI 0.94-0.98). CONCLUSION: The WCT Formula II is an example of how contemporary ECG interpretation software could be used to differentiate WCTs successfully.

Ablation using 3D maps adjusted for spatial displacement of premature ventricular complexes relative to sinus beats: Improving precision by correcting for the shift.

INTRODUCTION: Point-by-point 3-dimensional (3D) electroanatomic mapping (EAM) is used to guide catheter ablation of premature ventricular complexes (PVCs). Due to the differences in the spatial excursion of the cardiac chambers during cardiac cycles in PVCs vs sinus rhythm, the 3D location registration during PVCs is shifted relative to sinus rhythm. In this study, we describe our strategy to adjust for this displacement in real-time during PVC mapping. METHODS AND RESULTS: We report 21 patients who underwent catheter ablation of 23 unique PVCs using Carto 3. After mapping the earliest site for each PVC, we reregistered its 3D location to a sinus rhythm beat in real-time, and used this to guide ablation lesion delivery. The PVC earliest location was spatially displaced from the successful ablation lesion in sinus rhythm by average 6.7 (range 3.3-13.0) mm. Offline, we subsequently analyzed 25 unique chamber maps and 606 PVC points. For each point, we reregistered the 3D location to a preceding sinus beat. The PVC points were displaced from sinus rhythm location by average 4.4 (0.3-13.7) mm. The maximally displaced point for each chamber was 7.7 (4.7-13.7) mm. The general direction of shift during PVC was leftward and inferior relative to sinus rhythm. CONCLUSIONS: During electroanatomic mapping of PVCs using the Carto 3 system, points mapped during PVCs are spatially displaced relative to their location in sinus rhythm. Electrophysiologists should recognize this phenomenon and account for the shift to guide accurate delivery of ablation lesions.

Interaction of cardiac implantable electronic device and patent foramen ovale in ischemic stroke: A case-only study.

BACKGROUND: Cardiovascular implantable electronic device (CIED) leads are a nidus for right atrial thrombi. Right-to-left thromboembolism across a patent foramen ovale (PFO) is a putative mechanism for ischemic stroke and PFO has been associated with stroke. We used a novel unbiased case-only study design to assess the effect modification of PFO-associated ischemic stroke risk by presence of CIED. We hypothesized that presence of CIED, as a nidus for right atrial thrombus formation, magnifies the PFO-ischemic stroke relationship; therefore, among hospitalized ischemic stroke patients we would find a higher prevalence of CIED in patients with PFO. METHODS: We included consecutive first ischemic stroke patients admitted to our hospital from 2006 to 2015, who were enrolled in a prospectively maintained stroke registry. PFO was ascertained from documentation on echocardiography, and presence of CIED at time of stroke was determined from chest radiography reports at or prior to hospitalization. We measured distributions of CIED within PFO and control groups and used Fisher's exact test to evaluate the PFO-CIED association among ischemic stroke patients. RESULTS: We included 7089 patients (age: 64.5 ± 14.9 years, 51% female). Echocardiography diagnosed PFO in 760 (10.7%) patients and CIED was reported on chest radiography in 752 (10.6%) patients. Prevalence of CIED was lower in the PFO (61/760, 8.0%) compared to control group (691/6329, 10.9%), P = 0.015. CONCLUSION: Among admitted ischemic stroke patients, we did not find a higher prevalence of CIED in patients with PFO compared to controls. Therefore, in the underlying source population, the presence of CIED did not increase the PFO-associated ischemic stroke risk.

Phase I/II Trial of Electrophysiology-Guided Noninvasive Cardiac Radioablation for Ventricular Tachycardia.

BACKGROUND: Case studies have suggested the efficacy of catheter-free, electrophysiology-guided noninvasive cardiac radioablation for ventricular tachycardia (VT) using stereotactic body radiation therapy, although prospective data are lacking. METHODS: We conducted a prospective phase I/II trial of noninvasive cardiac radioablation in adults with treatment-refractory episodes of VT or cardiomyopathy related to premature ventricular contractions (PVCs). Arrhythmogenic scar regions were targeted by combining noninvasive anatomic and electric cardiac imaging with a standard stereotactic body radiation therapy workflow followed by delivery of a single fraction of 25 Gy to the target. The primary safety end point was treatment-related serious adverse events in the first 90 days. The primary efficacy end point was any reduction in VT episodes (tracked by indwelling implantable cardioverter defibrillators) or any reduction in PVC burden (as measured by a 24-hour Holter monitor) comparing the 6 months before and after treatment (with a 6-week blanking window after treatment). Health-related quality of life was assessed using the Short Form-36 questionnaire. RESULTS: Nineteen patients were enrolled (17 for VT, 2 for PVC cardiomyopathy). Median noninvasive ablation time was 15.3 minutes (range, 5.4-32.3). In the first 90 days, 2/19 patients (10.5%) developed a treatment-related serious adverse event. The median number of VT episodes was reduced from 119 (range, 4-292) to 3 (range, 0-31; P<0.001). Reduction was observed for both implantable cardioverter defibrillator shocks and antitachycardia pacing. VT episodes or PVC burden were reduced in 17/18 evaluable patients (94%). The frequency of VT episodes or PVC burden was reduced by 75% in 89% of patients. Overall survival was 89% at 6 months and 72% at 12 months. Use of dual antiarrhythmic medications decreased from 59% to 12% ( P=0.008). Quality of life improved in 5 of 9 Short Form-36 domains at 6 months. CONCLUSIONS: Noninvasive electrophysiology-guided cardiac radioablation is associated with markedly reduced ventricular arrhythmia burden with modest short-term risks, reduction in antiarrhythmic drug use, and improvement in quality of life. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov/ . Unique identifier: NCT02919618.

The Electrophysiological Substrate of Early Repolarization Syndrome: Noninvasive Mapping in Patients.

Background: The early repolarization (ER) pattern is a common ECG finding. Recent studies established a definitive clinical association between ER and fatal ventricular arrhythmias. However, the arrhythmogenic substrate of ER in the intact human heart has not been characterized. Objectives: To map the epicardial electrophysiological (EP) substrate in ER syndrome patients using noninvasive Electrocardiographic Imaging (ECGI), and to characterize substrate properties that support arrhythmogenicity. Methods: Twenty-nine ER syndrome patients were enrolled, 17 of which had a malignant syndrome. Characteristics of the abnormal EP substrate were analyzed using data recorded during sinus rhythm. The EP mapping data were analyzed for electrogram morphology, conduction and repolarization. Seven normal subjects provided control data. Results: The abnormal EP substrate in ER syndrome patients has the following properties: (1) Abnormal epicardial electrograms characterized by presence of J-waves in localized regions; (2) Absence of conduction abnormalities, including delayed activation, conduction block, or fractionated electrograms; (3) Marked abbreviation of ventricular repolarization in areas with J-waves. The action potential duration (APD) was significantly shorter than normal (196±19 vs. 235±21 ms, p<0.05). Shortening of APD occurred heterogeneously, leading to steep repolarization gradients compared to normal control (45±17 vs.7±5 ms/cm, p<0.05). Premature ventricular contractions (PVCs) were recorded in 2 patients. The PVC sites of origin were closely related to the abnormal EP substrate with J-waves and steep repolarization gradients. Conclusions: Early Repolarization is associated with steep repolarization gradients caused by localized shortening of APD. Results suggest association of PVC initiation sites with areas of repolarization abnormalities. Conduction abnormalities were not observed.

Electrophysiologic Scar Substrate in Relation to VT: Noninvasive High-Resolution Mapping and Risk Assessment with ECGI.

BACKGROUND: Ischemic cardiomyopathy (ICM) can provide the substrate for ventricular tachycardia (VT). OBJECTIVE: To map noninvasively with high resolution the electrophysiologic (EP) scar substrate, identify its relationship to reentry circuits during VT, and stratify VT risk in ICM patients. METHODS: Noninvasive high-resolution epicardial mapping with electrocardiographic imaging (ECGI) was performed in 32 ICM patients (17 with clinical VT, 15 without VT). Abnormal scar EP substrate was determined based on electrogram (EGM) amplitude (as percentage of maximal peak-to-peak voltage over the entire ventricular epicardium; total scar [TS] < 30%; dense scar [DS] < 15%), fractionation, and presence of late potentials (LPs). Scar burden was defined as the ratio of the scar size to the total epicardial surface area. The VT activation pattern was mapped and correlated with the EP substrate to identify components of the reentry circuit. RESULTS: Patients with VT had higher scar burden (TS: 51.0 ± 9.3% vs 36.5 ± 5.4%, P < 0.05; DS: 29.5 ± 7.3% vs 16.8 ± 6.8%, P < 0.05) with lower normalized unipolar EGM voltage (TS: 0.107 ± 0.027 vs 0.153 ± 0.031, P < 0.05; DS: 0.073 ± 0.023 vs 0.098 ± 0.026, P < 0.05), greater prevalence of fractionated EGMs (TS: 44.1 ± 10.6% vs 26.8 ± 6.3%, P < 0.05; DS: 50.8 ± 10.8% vs 30.9 ± 7.0%, P < 0.05), and LPs (TS: 26.8 ± 10.7% vs 15.8 ± 5.3, P < 0.05). VTs were mapped in eight patients; the reentry circuits were closely related to the EP substrate. CONCLUSIONS: ECGI noninvasively identified scar EP substrate that underlies abnormal conduction in ICM patients. It identified regions within the scar that aligned with critical elements of the reentry circuit during VT. ECGI can potentially be used for VT risk stratification in ICM patients.

Patients with Diabetes and Significant Epicardial Coronary Artery Disease Have Increased Systolic Left Ventricular Apical Rotation and Rotation Rate at Rest.

OBJECTIVE: The purpose of this study was to determine whether resting myocardial deformation and rotation may be altered in diabetic patients with significant epicardial coronary artery disease (CAD) with normal left ventricular ejection fraction. DESIGN: A prospective observational study. SETTING: Diagnosis of epicardial CAD in patients with diabetes. PATIENTS AND METHODS: Eighty-four patients with diabetes suspected of epicardial CAD scheduled for cardiac catheterization had a resting echocardiogram performed prior to their procedure. Echocardiographic measurements were compared between patients with and without significant epicardial CAD as determined by cardiac catheterization. MAIN OUTCOME MEASURES: Measurement of longitudinal strain, strain rate, apical rotation, and rotation rate, using speckle tracking echocardiography. RESULTS: Eighty-four patients were studied, 39 (46.4%) of whom had significant epicardial CAD. Global peak systolic apical rotation was significantly increased (14.9 ± 5.1 vs. 11.0 ± 4.8 degrees, P < 0.001) in patients with epicardial CAD along with faster peak systolic apical rotation rate (90.4 ± 29 vs. 68.1 ± 22.2 degrees/sec, P < 0.001). These findings were further confirmed through multivariate logistic regression analysis (global peak systolic apical rotation OR = 1.17, P = 0.004 and peak systolic apical rotation rate OR = 1.05, P < 0.001). CONCLUSIONS: Patients with diabetes with significant epicardial CAD and normal LVEF exhibit an increase in peak systolic apical counterclockwise rotation and rotation rate detected by echocardiography, suggesting that significant epicardial CAD and its associated myocardial effects in patients with diabetes may be detected noninvasively at rest.

Repolarization changes underlying long-term cardiac memory due to right ventricular pacing: noninvasive mapping with electrocardiographic imaging.

BACKGROUND: Cardiac memory refers to the observation that altered cardiac electrical activation results in repolarization changes that persist after the restoration of a normal activation pattern. Animal studies, however, have yielded disparate conclusions, both regarding the spatial pattern of repolarization changes in cardiac memory and the underlying mechanisms. The present study was undertaken to produce 3-dimensional images of the repolarization changes underlying long-term cardiac memory in humans. METHODS AND RESULTS: Nine adult subjects with structurally normal hearts and dual-chamber pacemakers were enrolled in the study. Noninvasive electrocardiographic imaging was used before and after 1 month of ventricular pacing to reconstruct epicardial activation and repolarization patterns. Eight subjects exhibited cardiac memory in response to ventricular pacing. In all subjects, ventricular pacing resulted in a prolongation of the activation recovery interval (a surrogate for action potential duration) in the region close to the site of pacemaker-induced activation from 228.4±7.6 ms during sinus rhythm to 328.3±6.2 ms during cardiac memory. As a consequence, increases are observed in both apical-basal and right-left ventricular gradients of repolarization, resulting in a significant increase in the dispersion of repolarization. CONCLUSIONS: These results demonstrate that electrical remodeling in response to ventricular pacing in human subjects results in action potential prolongation near the site of abnormal activation and a marked dispersion of repolarization. This dispersion of repolarization is potentially arrhythmogenic and, intriguingly, was less evident during continuous right ventricular pacing, suggesting the novel possibility that continuous right ventricular pacing at least partially suppresses pacemaker-induced cardiac memory.