The American Journal of Cardiology

Background: Anatomic isthmus 3 (AI 3) is defined as the myocardium between the pulmonary valve annulus and the ventricular septal defect patch that persists after tetralogy of Fallot (ToF) repair. Ventricular tachycardia (VT) propagated through slow conducting AI 3 (SCAI 3) represents a significant cause of morbidity in ToF. There is an unmet need for non-invasive identification of SCAI 3 in patients with ToF. Objectives: To assess whether the anatomic features of AI 3 as derived from cardiac computed tomography (CT) can predict slow conduction velocity during EP study. Methods: This retrospective single-center study included patients with ToF who underwent an electrophysiologic study and had AI 3 width measured from the pre-procedure cardiac CT. All patients underwent programmed ventricular stimulation, and electroanatomic. Logistic regression was performed to assess the relationship between AI 3 width and the presence of SCAI 3. Results: Of 27 consecutive patients with ToF, twelve patients were found to have SCAI 3, and ten patients were found to have SCAI 3 mediated VT. The AI 3 was significantly narrower in patients with SCAI 3 compared to those with normal AI 3 conduction (18.4 +/- 6.6 mm vs. 29.2 +/- 9.0 mm; p = 0.001). An AI 3 width above 21.5 mm carried a negative predictive value of 80.0%. Conclusion: In adults with repaired ToF referred for electrophysiology study, a narrower CT-derived AI 3 width was associated with SCAI 3 identification. AI 3 width measured on a CT obtained before PV replacement could help guide invasive risk stratification.

Background Real-world data regarding mavacamten use in underserved and racially diverse populations remain limited, particularly for long-term therapy implementation. Structural barriers such as financial instability, fragmented healthcare access, and challenges adhering to REMS-related monitoring requirements may affect longitudinal therapy implementation. Methods We performed a retrospective observational study of consecutive patients with symptomatic obstructive hypertrophic cardiomyopathy (oHCM) evaluated for mavacamten therapy at a tertiary HCM center in Bronx, NY, between 6/2022-10/2025. Patients were followed for up to 48 weeks after treatment initiation. Clinical characteristics, treatment interruptions, adverse events, echocardiographic and functional outcomes, and implementation barriers were assessed descriptively. Results Seventy-two patients with symptomatic oHCM were evaluated for mavacamten; sixty-seven initiated treatment. Mean age was 66.9{+/-}15.3 years, 72% were female, and 61% identified as Black or Hispanic. Median resting left ventricular outflow tract (LVOT) gradient decreased from 51mmHg (IQR30-88) at baseline to 7mmHg (IQR5-10) at 48 weeks. Median Valsalva LVOT gradient decreased from 74mmHg (IQR50-104) to 20mmHg (IQR10-29). At final follow-up, 80% of patients improved by [≥]1 NYHA functional class. LVEF declined below 50% in five patients and recovered in all cases. Approximately one-quarter experienced treatment interruption or discontinuation, nearly half related to insurance instability, non-adherence, and REMS-related monitoring barriers. Conclusions Mavacamten demonstrated efficacy and safety outcomes comparable to those reported in clinical trials and prior registries in this predominantly underserved minority urban cohort. However, structural and healthcare-access barriers substantially affected long-term treatment implementation. These findings highlight the need to address healthcare-system barriers to ensure equitable implementation of contemporary HCM therapies.

Background Pulsed-field ablation (PFA) has recently been approved in the USA as a new method for treating atrial fibrillation (AF). PFA provides a promising new approach in the treatment of atrial fibrillation (AF), which historically has a high recurrence rate post-ablation. Of significance, PFA has shown promising data in terms of safety and procedural efficiency to radiofrequency ablation (RFA). Objective The purpose of this study was to compare the procedural and health outcomes in patients with recurrent AF undergoing ablation using PFA or RFA. Methods Consecutive patients with a history of previous radiofrequency ablation and recurrent AF undergoing redo ablation with PFA or RFA were included. Patients were seen for follow-up in the clinic ranging from 4 months to a year and we reported ablation strategy and arrhythmia type. The primary outcome was recurrence of any atrial arrhythmia after a 90-day blanking period. Results A total of 242 patients with recurrent AF underwent redo ablation using PFA (n = 54, 22.5%) or RFA (n = 188, 77.5%). The PFA cohort was younger on average (66 vs. 70 years) with a lower mean CHA2DS2-VASc score (2.2 vs. 3.06, p=0.001) compared to the RFA cohort. PFA procedures were shorter (162{+/-}53 vs 206{+/-}60 minutes, p<0.001) but required more fluoroscopy (13.9{+/-}8.9 vs 8.7{+/-}6.3 minutes, p<0.001). Among patients seen on follow-up, recurrence occurred in 28% of PFA versus 55% of RFA patients, with longer arrhythmia-free survival after PFA (log-rank p=0.03). PFA remained associated with lower recurrence after multivariable adjustment (HR 0.4, 95% CI 0.2?0.9, p=0.04). Adverse events, predominantly vascular access?related, were similar. Conclusion Among patients with recurrent atrial arrhythmias after prior RFA, repeat PFA was associated with shorter procedures, greater fluoroscopy use, and lower arrhythmia recurrence, with comparable safety.

Background: Growth differentiation factor 15 (GDF-15) has emerged as a prognostic biomarker in patients with non-ST-segment-elevation acute coronary syndrome (NSTE-ACS). Our study evaluated the temporal evolution of GDF-15 in the acute phase and its association with recurrent ischemic events. Methods: Serum samples were collected from patients with NSTE-ACS at admission and at 1 and 3 hours after admission. GDF-15 levels, along with other prognostic biomarkers, NT-proBNP and hs-cTnT, were measured. Spearman rank-correlation coefficients and linear regression models were used to identify the variables associated with GDF-15 levels at admission and with their temporal changes. Associations between GDF-15 and clinical outcomes were evaluated using Cox proportional hazards models. To assess incremental prognostic value, the areas under the curve (AUC) were calculated for each model. Results: GDF-15 levels showed a slight increasing trend within 3 hours of admission. The 1-hour change in GDF-15 was correlated with hs-cTnT changes. Increased 1-hour GDF-15 levels, compared with the admission levels, were associated with a higher risk of recurrent ischemic events during the 1-year follow-up (1.9% vs. 17.5%, P =0.019) and were an independent predictor after adjusting for established clinical variables and biomarkers (adjusted hazard ratio, 1.71 (1.28 to 228.75), P =0.03). Furthermore, serial measurements of GDF-15 provided additional prognostic information beyond traditional risk factors. Conclusions: Serial measurements of GDF-15 of NSTE-ACS patients provided independent and incremental prognostic value for predicting recurrent ischemic events. These findings support the potential utility of GDF-15 as a dynamic biomarker for early risk stratification in the acute management of NSTE-ACS.

Background: Mitral valve prolapse (MVP) causes mitral regurgitation (MR), leading to volume overload and maladaptive left ventricular (LV) remodelling. Objective: To comprehensively characterize markers of maladaptive LV remodelling across MR severity grades in MVP using cardiovascular magnetic resonance (CMR), and their association with functional status. Methods: Patients with MVP undergoing 1.5T CMR (2016-2025) were stratified by MR fraction: mild<20%, moderate 20-39%, and severe [&ge;]40%. Exclusion criteria were significant coronary artery disease, rheumatic valve disease, mitral stenosis, previous mitral valve procedures, endocarditis or signs of primary cardiomyopathy. Global native T1, T2, extracellular volume (ECV), indexed ECV (iECV), indexed intracellular volume (iICV), and late gadolinium enhancement (LGE) were quantified. Indexed LV end-diastolic volume (EDVI) and the EDV-to-LV mass ratio (EDV/LVM-ratio) were also calculated as indices of LV remodelling and adaptive hypertrophy. Functional status was assessed by NYHA class. Results: Among 112 MVP patients (23 mild, 48 moderate, 41 severe MR) and 20 controls, LGE prevalence (17% vs. 46% vs. 51% vs. 0%) and the proportion with LV dilatation (46% vs. 67% vs. 88% vs 15%) rose progressively with MR severity. Increased EDVI, prevalence of LGE, higher EDV/LVM-ratio, global native T1 and iECV showed the strongest associations with more severe MR, whereas EDV/LVM-ratio, iECV and global native T1 were independently related to NYHA class[&ge;]II. Conclusions: CMR markers of maladaptive LV remodelling were abnormal across all MR grades and increased markedly with MR severity. Global native T1, iECV and EDV/LVM-ratio correlated most strongly with symptom burden, rather than MR severity per se.

Background: Pacing-induced cardiomyopathy (PICM) is a major complication of chronic right ventricular pacing and develops in up to 25% of patients. Reliable prediction of PICM may facilitate individualized pacing strategy selection; however, currently available approaches demonstrate limited discriminative performance. This study aimed to develop and validate machine learning (ML) models for predicting PICM in patients with atrioventricular block (AVB) underlying heart failure with mildly reduced or preserved ejection fraction. Methods: In this multicenter prospective study derived from the RISK-PICM registry (January 2002 to January 2026), 125 patients with AVB who underwent pacemaker implantation were analyzed. PICM was defined as a ?10% reduction in left ventricular ejection fraction (LVEF) resulting in an LVEF <50%. Four ML algorithms, including logistic regression, support vector machine, random forest, and XGBoost, were trained using stratified 4-fold cross-validation with hyperparameter optimization and model discrimination was evaluated. Results: PICM developed in 41 patients (32.8%) during a median follow-up of 4.8 years. Male sex, pre-implant minimum QTc interval, and post-implant maximum QRS duration were significantly associated with PICM in univariable Cox regression. XGBoost achieved the highest discriminative performance (AUROC 0.831; sensitivity 0.805; specificity 0.845). Feature importance analysis identified baseline LVEF and post-implant maximum QRS duration as the most influential features. Model-derived risk stratification significantly differentiated high-risk and low-risk groups on Kaplan-Meier analysis (P < 0.001). Conclusions: ML-based models, particularly XGBoost, demonstrated clinically meaningful performance for PICM and may support individualized pacing strategy selection in patients with AVB and underlying heart failure with mildly reduced or preserved ejection fraction.

Background: Mitral regurgitation (MR) is a common complication of mitral valve prolapse (MVP) and increases left ventricular (LV) preload, promotes LV remodeling and hypertrophy, but its impact on myocardial perfusion and coronary microvascular dysfunction remains unclear. Objectives: To assess myocardial perfusion using, for the first time, quantitative cardiac magnetic resonance (CMR) perfusion mapping in patients with significant MR due to MVP. Methods: Patients with significant primary MR, without coronary artery disease were prospectively enrolled and compared to age- and sex-matched controls without MR. All underwent 1.5T CMR including cine imaging, adenosine stress perfusion, native T1, native T2, extracellular volume (ECV) mapping and late gadolinium enhancement (LGE). Myocardial perfusion reserve (MPR) was calculated as the ratio of stress to rest myocardial perfusion. Results: In total 33 patients and 33 controls were included (age 56{+/-}13 vs. 58{+/-}12 years, 46% women in both groups). Patients with MR had increased LV mass and volumes, higher native T1 and ECV and a higher prevalence of LGE (36% vs 0%). No differences were observed in global myocardial perfusion at rest (0.88{+/-}0.27 vs. 0.85{+/-}0.30, p=0.52), at stress (2.6{+/-}0.56 vs. 2.8{+/-}0.73 ml/min/g, p=0.29) or for MPR (3.1{+/-}0.75 vs. 3.4{+/-}1.0, p=0.24). In age- and sex-adjusted linear regression, higher NYHA class was associated with lower MPR (0.60, p=0.04). Conclusion: In patients with significant MR due to MVP, myocardial perfusion appears preserved despite LV volume overload. However, lower MPR in symptomatic patients suggests that microvascular dysfunction may emerge in a more advanced disease stage.

Background: Atrial fibrillation (AF) has been observed in adults with anomalous pulmonary venous return (APVR), but data on catheter ablation outcomes in this population remain limited to case reports and small series. Methods: We retrospectively reviewed 14 adult patients with confirmed APVR who underwent catheter ablation for AF at three tertiary academic centers in the United States between July 2003 and May 2025. Baseline, procedural, electroanatomic mapping, and outcome data were collected. Freedom from atrial arrhythmia recurrence was estimated by Kaplan-Meier analysis. Results: Mean age was 56 +/- 13 years and 79% were male. Heart failure was present in 64%, and hypertension and coronary artery disease in 43% each. Most had partial APVR (86%), and 57% had prior surgical correction. Radiofrequency ablation was used in all patients, combined with pulsed-field ablation in one. Acute success was achieved in all patients, although areas with residual pulmonary vein or SVC electrical activity were left untreated in 3 (21%). Non-pulmonary-vein electrical activity was more common in patients with prior surgical correction than in those without (43% vs 17%). Median follow-up was 3.4 years (IQR, 2.0-9.6). Freedom from arrhythmia recurrence was 78.6% at 1 year and 53.9% at 5 years. Two patients (14%) required reablation; complications occurred in 3 (21%) without long-term sequelae. Conclusions: Catheter ablation was acutely successful in all patients in this largest reported APVR cohort, despite substantial comorbidity burden and anatomic complexity. The arrhythmogenic substrate often extended beyond the anomalous vein, particularly in surgically corrected patients, supporting individualized, substrate-guided ablation in this population.

Condensed Abstract: Using the 2016?2022 National Inpatient Sample, this study evaluated temporal trends and demographic adoption patterns of percutaneous left atrial appendage occlusion (LAAO). Among 190,020 weighted procedures, annual volume increased from 4,875 to 60,445. In-hospital mortality was exceptionally low (0.1%). Age-adjusted procedural rates rose from 34.19 to 379.87 per 100,000 population. However, significant disparities persisted, characterized by heavy centralization in urban teaching hospitals (87.0%) and disproportionately lower absolute age-adjusted utilization among female, Black, Hispanic, and Asian/Pacific Islander patients compared to male and White cohorts. Targeted initiatives are needed to ensure equitable access to structural heart interventions.

Background: Transthoracic echocardiography (TTE) remains the gold standard for assessing left ventricular (LV) diastolic dysfunction (DD), but noninvasive alternatives are needed to overcome geometric and acoustic limitations. 4D-Flow MRI enables comprehensive assessment of intraventricular pressure differences (IVPDs) and flow propagation velocity (VP). We aimed to evaluate 4D-Flow-derived IVPDs and VP in patients with hypertrophic cardiomyopathy (HCM). Methods: Thirty-eight HCM patients and 38 age- and sex-matched healthy controls underwent TTE and 4D-Flow MRI. Spatiotemporal maps of velocity and IVPDs, decomposed into inertial and convective components, were derived along the main inflow streamline from the mitral valve to the apex. Peak early filling rate (PEFR) was used to normalize IVPDs and VP. Results: While absolute peak flow rates were comparable, HCM patients exhibited significantly faster VP (100.4 vs. 60.2 cm/s, p < 0.01) and higher positive early E IVPD (1.40 vs. 0.92 mmHg, p < 0.01) compared to controls. Normalizing IVPDs by PEFR amplified group differences, revealing a markedly increased flow-normalized E-IVPD (5.13 vs. 2.94 x 103 mmHg.ml1.s, p < 0.001) and deeper reverse ER IVPD (-6.06 vs. -4.61 x 103 mmHg.ml1.s, p < 0.01) in HCM. These differences were primarily driven by the inertial components. Multivariable analysis demonstrated that ER IVPD is independently determined by PEFR and the TTE E/E' ratio (r = 0.65, p < 0.001). Conclusions: 4D-Flow MRI-derived, flow-normalized IVPDs and propagation velocity provide robust, noninvasive markers of altered LV chamber stiffness and impaired diastolic filling in HCM, offering deeper 3D hemodynamic insights into diastolic dysfunction.

Background: Tirzepatide and semaglutide improve functional status and heart failure (HF) events in patients with obesity and HF with preserved ejection fraction. Tirzepatide has been associated with greater control of cardiometabolic risk factors in patients with obesity compared to semaglutide. Whether tirzepatide is associated with lower risk of new-onset HF than semaglutide in patients with obesity is underexplored. Methods: A retrospective cohort study was conducted using data pooled from the TriNetX platform. Patients with obesity who initiated therapy with tirzepatide or semaglutide during the period Jun 4, 2021 to Aug 13, 2026 were identified and 1:1 propensity-score matched to produce two study cohorts. The one-year incidence of new-onset HF was calculated and compared between the two cohorts. Secondary outcomes included new-onset systolic HF, new-onset diastolic heart failure, new-onset atrial fibrillation or flutter, all-cause mortality, and hospital encounters. Cox proportional hazards models were fitted to calculate hazard ratios (HR) along with 95% confidence intervals (CI). Results: Two well-matched cohorts (N=424,269 in each) were formed. The incidence of new-onset HF was lower in the tirzepatide group (1.0% vs. 1.3%; absolute risk difference -0.3%, 95% CI -0.35 to -0.26; HR 0.9, 95% CI 0.86[boxh]0.93). The tirzepatide group were also at lower risk of all-cause mortality (HR, 95% CI: 0.8, 0.77[boxh]0.91) and new-onset systolic HF (0.8, 0.79[boxh]0.92). All other secondary outcomes occurred at similar rates in both study groups. Conclusion: Among patients with obesity, tirzepatide therapy was associated with lower risk of new-onset HF compared to semaglutide although the effect sizes were modest.

Aims: Myocardial strain enables sensitive assessment of cardiac function, but its clinical application has largely focused on individual chambers or selected patient populations. We evaluated the feasibility and clinical relevance of fully automated multi-chamber strain assessment in consecutive patients undergoing routine transthoracic echocardiography (TTE). Methods and results: This retrospective study included 8,350 consecutive adults undergoing TTE. A hospital-wide artificial intelligence (AI)-based system automatically measured left ventricular (LV) global longitudinal strain (LVGLS), left atrial (LA) reservoir strain (LASr), and right ventricular (RV) free-wall strain (RVFWS). AI-derived LVGLS was available from at least one apical view in 97.1% of patients and from all three views in 94.8%; LASr and RVFWS were available in 94.1% and 94.5%, respectively, resulting in complete multi-chamber strain assessment in 90.3%. Strain measures showed modest correlations with conventional chamber-specific echocardiographic parameters and differential associations with clinical outcomes. Gaussian mixture modeling identified three distinct clusters characterized by preserved multi-chamber function, RV-dominant dysfunction, and pan-chamber dysfunction. Compared with the preserved cluster, pan-chamber dysfunction was associated with the highest risk of all-cause death or heart failure hospitalization (adjusted hazard ratio, 3.44; 95% CI, 2.43-4.88; P<0.001). Prognostic associations remained evident in patients with LV ejection fraction (LVEF) [&ge;]50%, and cluster assignment provided incremental prognostic information beyond clinical factors, LVEF, and RV fractional area change. Conclusions: Fully automated multi-chamber strain assessment was feasible in a large consecutive TTE cohort. Integrating strain across cardiac chambers may provide complementary functional characterization and identify clinically relevant clusters with prognostic information beyond conventional assessment.

Abstract Background The SYNTAX score (SS) quantifies the severity and complexity of coronary artery lesions and serves as an independent predictor of major adverse cardiovascular events and mortality in patients with acute coronary syndrome (ACS). However, few studies have examined the association between SS and in-hospital cardiac arrest (IHCA) in this population. Therefore, this study aims to elucidate the relationship between SS and the incidence of IHCA in patients with ACS. Methods This study consecutively enrolled 3,224 patients undergoing percutaneous coronary intervention (PCI). Logistic regression and restricted cubic spline (RCS) analyses were employed to examine the association between SS and the incidence of IHCA. Participants were stratified into three groups based on SS: Group T1 (SS ? 10, N = 1,097), Group T2 (10 < SS ? 18, N = 1,089), and Group T3 (SS > 18, N = 1,038). The primary endpoint was the incidence of IHCA. Results The overall incidence of IHCA was 4% (N=147). After adjusting for covariates, SS was significantly associated with the incidence of IHCA in ACS patients treated with PCI (OR = 1.0400; 95% confidence interval (CI) = 1.0200?1.0700; p < 0.001). Compared with the T1 group, the T3 group exhibited an increased risk of IHCA (OR = 2.1800; 95% CI = 1.2900?3.6900; p = 0.0040). Subgroup analyses revealed that, after covariate adjustment, patients with ST-segment elevation myocardial infarction (STEMI) had an increased risk of IHCA (OR = 1.0700; 95% CI = 1.0300?1.1100; p < 0.001). Similarly, both patients with diabetes mellitus (DM) (OR = 1.0400; 95% CI = 1.000?1.0700; p = 0.0270) and those without DM (OR = 1.0600; 95% CI = 1.0200?1.1000; p = 0.0020) showed an increased risk. Furthermore, elderly patients (?60 years) (OR = 1.0300; 95% CI = 1.0100?1.0700; p = 0.0210) and non-elderly patients (<60 years) (OR = 1.0500; 95% CI = 1.000?1.1000; p = 0.0470) had an increased risk, as did male patients (OR = 1.0500; 95% CI = 1.0200?1.0700; p = 0.0020). RCS analysis indicated a dose-response relationship between IHCA incidence and SS (nonlinear p-value = 0.906), with the risk of IHCA increasing when SS exceeded 23.975. Incorporating SS into the baseline risk model improved the predictive value for IHCA incidence in ACS patients undergoing PCI (Net reclassification improvement [NRI]: 0.3537 [0.1906?0.5167], p < 0.001; Integrated discriminant improvement [IDI]: 0.0104 [0.0025?0.0183], p = 0.0097). Conclusions Among patients with ACS undergoing PCI, SS is significantly associated with the incidence of IHCA. Consequently, SS may serve as an effective predictor of IHCA in this population.

Background: Sleep-disordered breathing (SDB) is an established adverse prognostic factor in heart failure (HF). Sleep apnea-specific hypoxic burden (SASHB), which reflects the duration and depth of respiratory event-related oxygen desaturation, has shown stronger prognostic value than the apnea-hypopnea index (AHI) in general populations and patients with coronary artery disease. However, its clinical utility in patients hospitalized due to acute HF remains unclear. Objectives: This study evaluated the prognostic value of SASHB in patients hospitalized for acute HF and compared its performance with AHI for risk stratification and identification of patients who may benefit from positive airway pressure (PAP) therapy. Methods: This post hoc analysis included 230 patients from a prospective single-center observational cohort of adults hospitalized for acute HF. The primary analysis included 178 patients who did not receive PAP treatment. Associations of SASHB and AHI with the composite endpoint of cardiovascular death or rehospitalization for worsening HF were evaluated using Cox proportional hazards models. Model improvement after adding SASHB or AHI to a model including established clinical risk factors was assessed using changes in the C index and Brier score, reflecting changes in model discrimination and prediction error, respectively. In the full cohort, the interaction between PAP treatment and SDB metrics was evaluated using the g-formula. Results: During a median follow-up of 3.7 years, 58 of 178 patients (32.6%) reached the composite endpoint. Both SASHB and AHI were independently associated with the composite outcome after multivariable adjustment. However, only SASHB consistently predicted outcomes across analyses and improved model performance beyond established prognostic factors (bootstrap {Delta} C index, 0.020 [95% CI: 0.008 - 0.031]; bootstrap {Delta} Brier score, - 0.007 [95% CI: - 0.014 to - 0.001]), whereas AHI did not. In the analysis including PAP-treated patients, both SASHB and AHI showed interaction with PAP treatment. Conclusions: In patients hospitalized for acute HF, SASHB showed a consistent independent association with adverse clinical outcomes and provided additional prognostic information beyond AHI. SASHB may improve risk stratification and may help identify patients who are more likely to benefit from PAP therapy.

BACKGROUND: Hypertrophic cardiomyopathy (HCM) is a pan-ethnic disease, at least as common in Black as in White Americans, yet Black patients reach specialist care later, undergo septal reduction less often, and die sooner. Whether the defining trials enrolled representatively is unknown. We sought to measure Black participation in the landmark HCM trials against three expectations of increasing stringency, and to test whether trial site geography or quantitative eligibility thresholds account for the shortfall. METHODS: Of 197 registered interventional HCM trials, 32 met prespecified landmark tiers; demographics were extracted for 16 and 13 reported race. The Black share of Black plus White participants was pooled by random-effects meta-analysis and compared with the US adult population, with each trial?s own site counties, and with a disease-referenced echocardiographic expectation. Site geography and eligibility thresholds were tested using site addresses, census data, and NHANES. RESULTS: Across 13 trials, 70 of 1,780 Black or White participants were Black. The pooled Black share was 3.98% (95% CI 2.68-5.86), against a population expectation of 16.5%, giving a participation-to-prevalence ratio (PPR) of 0.24 (95% CI 0.16-0.36), the lowest of any racial and/or ethnic minority group. The clinical trial site network reached 63.7% of Black and 47.5% of White US adults, with geospatial analysis predicting 26.4% Black enrollment; however, every trial fell below this expectation. Quantitative eligibility thresholds closed only 2.0% of the enrollment gap. CONCLUSIONS: Black participation was about one quarter of the population expectation. Neither site geography nor eligibility thresholds explain it.

Background: Pulsed field ablation (PFA) has been rapidly adopted for atrial fibrillation (AF) on the premise of greater safety than thermal ablation. Real-world signals of hemolysis, coronary spasm, and neurologic events have since emerged, and prior Manufacturer and User Facility Device Experience (MAUDE) analyses relied on term matching without prospective signal detection. Methods: We queried MAUDE for AF ablation catheter reports received January 2016 through June 2026 and assigned each to PFA, radiofrequency ablation (RFA), or cryoballoon ablation. We adjudicated injury and death narratives into predefined complication families and severity tiers with a large language model, checked against a larger model and by physician review. We calculated reporting odds ratios (ROR) and Bayesian shrinkage estimators compared against an empirical null, applied interrupted time series and prospective sequential detection, and repeated estimates on a 2026 hold-out. Results: Among 44,623 reports, 30.1% were PFA, 50.9% RFA, and 19.0% cryoballoon, with 91.8% model agreement on event occurrence (? = 0.83). PFA carried an ROR of 527 (95% CI, 33, 8,509) for hemolysis, 2.83 (2.55, 3.16) for arrhythmia, 2.83 (2.30, 3.48) for coronary, and 2.39 (2.10, 2.73) for cerebrovascular events, against 0.024 (0.008, 0.075) for esophageal and 0.34 (0.32, 0.37) for pericardial events. The cerebrovascular excess was largest for VARIPULSE, but without it the class proportional reporting ratio was 1.36 (1.13, 1.65), concordant with the 1.56 measured in EMBOL-AF. In the hold-out, the cerebrovascular, arrhythmia and hemolysis signals replicated, and coronary events kept their direction without meeting the signal rule. Prospective detection flagged cerebrovascular events 13 months before AVANT GUARD published its neurologic events. Conclusions: PFA showed disproportionate reporting of hemolysis, cerebrovascular, coronary, and arrhythmic events across sequential testing. Machine learning methods allowed for flagging these signals months before confirmatory trials, demonstrating a scalable tool for early detection of procedural risk.

BACKGROUND: Because of the high mortality rate associated with fulminant myocarditis (FM), there is limited evidence regarding the prognostic efficacy of endomyocardial biopsy (EMB). In this study, we aimed to evaluate the influence of EMB in the early phase after admission on treatment and prognosis in FM using a large-scale nationwide registry in Japan. METHODS: Patients with FM who required catecholamine or mechanical circulatory support between 2012 and 2017 from 235 hospitals across Japan were included. The primary outcome of death or heart transplantation within 90 days according to performance of early EMB were determined using Kaplan-Meier and Cox regression analyses. Factors associated with performance of early EMB, and subsequent medical treatment were analyzed. RESULTS: The median age of 736 patients with clinical FM was 56 years, and 407 patients (55%) received EMB. Most EMB (89%) were performed during the early phase (within 5 days of admission) and 63% were performed on the first day of admission. The prognosis of FM patients who underwent EMB was more favorable than that of those who did not based on the landmark analysis (log-rank test, P=0.04). Factor analysis demonstrated that FM patients who underwent EMB had a lower left ventricular ejection fraction, higher incidence of cardiogenic shock on admission, and higher rate of early mechanical circulatory support, as well as early initiation of corticosteroids and guideline-directed medical therapy (GDMT) for heart failure. Absence of any GDMT was associated with a less favorable prognosis on multivariate analysis (hazard ratio, 4.34 [95% CI, 3.14?6.01]; P<0.0001). CONCLUSIONS: Although performing EMB in the early phase after admission depends on disease severity in FM patients, it is associated with early initiation of advanced medical treatment and may contribute to improving the prognosis.

Background Patients with normal perfusion, normal myocardial flow reserve (MFR) and no coronary artery calcium (CAC) on myocardial perfusion imaging are considered low risk. Yet, adverse events still occur and no routinely reported imaging marker stratifies residual risk. This study aims to determine whether fully automated ascending aortic calcification (AAC) from the attenuation correction CT stratifies risk in these patients. Methods In the multicenter REFINE-PET registry, AAC was quantified from non-contrast CT using deep learning aortic segmentation and Agatston scoring. Triple-normal was defined as stress total perfusion deficit (TPD) <5%, MFR >2 and CAC 0. The primary endpoint was cardiovascular death, myocardial infarction or heart failure admission, with heart failure admission as key secondary endpoint. Cox models were adjusted for clinical confounders. Results Of 21,923 patients, 3,580 (16.3%) were triple-normal, of whom 1,322 (36.9%) had AAC (median Agatston 65, IQR 22-212). Agreement with three blinded readers was good to excellent (Intraclass correlation coefficient 0.87-0.90). Over a median follow-up of 52 months (IQR 26-69), 194 primary events occurred. Per standard deviation, AAC was independently associated with the primary endpoint (adjusted HR 1.24, 95% CI 1.09-1.40; p<0.001), heart failure admission (adjusted HR 1.30, 95% CI 1.10-1.55; p=0.003) and all-cause mortality (adjusted HR 1.17, 95% CI 1.04-1.32; p=0.009). AAC improved model fit beyond clinical factors, MFR and TPD (p< or =0.009), with modest gains in discrimination ({Delta}C 0.007-0.009). Conclusions In patients with normal PET readouts, automated AAC was independently associated with adverse outcomes, most strongly heart failure admission, beyond clinical risk factors, perfusion and flow.

Rural patients with heart failure (HF) have poor access to care, worse outcomes, and may benefit from at-home monitoring. We evaluated whether foot temperature measured using a thermographic floor mat was associated with invasively measured cardiac output and whether longitudinal temperature changes preceded HF events. We conducted a two-part prospective, observational single-center study using the SmartMat (Podimetrics, Somerville, MA), which acquires plantar thermograms and ambient temperature. In the acute study, patients undergoing clinically indicated right heart catheterization completed 4 scans on the same day. In the chronic study, patients with a HF hospitalization in the past year and New York Heart Association Class II-III symptoms were instructed to use the device and a scale daily for 6 months. A HF event was defined as receiving at least one dose of intravenous or subcutaneous diuretic. Thirty patients were enrolled in the acute study. Mean right hallux temperature positively correlated with thermodilution cardiac output (r=0.63, p<0.001). 42 patients were enrolled in the chronic study. Among patients experiencing an HF event, ambient-adjusted hallux temperature declined in the 15 days immediately preceding the event compared with days 15-30 before the event. Plantar thermograms are associated with invasively measured cardiac output and may detect subclinical worsening before HF events. Foot temperature may provide complementary information regarding HF decompensation, supporting further evaluation of plantar thermography for remote HF monitoring.

Background: Cardiovascular (CV) screening is critical for personnel deploying to Antarctica, where geographic isolation and limited medical care make the management of acute cardiovascular events challenging. The utility of contemporary risk prediction tools such as the AHA PREVENT equations in this unique population remains uncertain. Methods: We retrospectively analyzed 154 individuals referred for enhanced CV evaluation before deployment to the U.S. Antarctic Program (USAP). Participants were evaluated across three temporal cohorts (2018-2020, 2021-2023, and 2024-2026). Demographics, CV risk factors, cardiac testing, and deployment clearance outcomes were collected. Risk was estimated using the Framingham Risk Score (FRS), AHA/ACC Pooled Cohort Equations (PCE), and AHA PREVENT risk models. Results: The cohort was predominantly male (79.9%; mean age 44.6 {+/-} 14.6 years), and abnormal ECG was the most common referral trigger (70.8%). Median 10-year risk was low by PREVENT and FRS and borderline elevated by PCE (PREVENT 2.7% [IQR 1.1-6.6], FRS 2.3% [IQR 0.5-7.1], and PCE 6.1% [IQR 2.4-9.2]). Among 72 participants with all scores, 51% were classified discordantly; PREVENT ASCVD agreed closely with FRS (=0.77) but poorly with PCE (=0.24-0.35), which consistently estimated higher risk. PCE was calculable in 52.6% versus 70.8% for PREVENT. Overall, 132 participants (85.7%) were cleared for deployment, while 8 (5.2%) were not physically qualified (NPQ); 6 of these NPQs were due to cardiovascular causes. Of 22 cardiac medical evacuations during the study period, 21 involved individuals without prior advanced cardiovascular screening. One screened individual was evacuated for symptoms subsequently found to have no cardiac cause. Conclusions: Risk calculators disagree substantially in the fitness-selected population. We recommend PREVENT as the primary risk-stratification tool as it is the most contemporary derivation, incorporates renal function, is race-agnostic, extends to heart failure, applies from age 30, and agrees closely with FRS, easing transition. Targeted imaging, including coronary artery calcium scoring, may supplement intermediate-risk candidates.