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Abdelnabi, Mahmoud

0000-0001-8016-9049

A5128046825 | I4210125099

Mayo Clinic

Mayo Clinic in Arizona

Citations 17

Connective tissue disorders and cardiac arrhythmias: genetic pathways, mechanistic bridges, and clinical implications

Frontiers in Cardiovascular Medicine | September 3, 2026 | Volume: 13 | Issue: No issue available | Pages: No page available

10.3389/fcvm.2026.1860012 | PMID 42755424

Background Connective tissue disorders (CTDs) such as Marfan syndrome, Loeys-Dietz syndrome, and Ehlers-Danlos syndromes are traditionally defined by vascular fragility and aortic complications. Increasing evidence, however, demonstrates that CTDs also predispose to atrial and ventricular arrhythmias, often independent of overt cardiomyopathy or severe valvular disease. Content This review integrates emerging data on the arrhythmogenic substrates of CTDs. Four mechanistic bridges are emphasized: (1) diffuse myocardial fibrosis driven by dysregulated TGF-β signaling, (2) structural valve and annular abnormalities, particularly mitral valve prolapse and mitral annular disjunction, (3) altered mechanotransduction linking extracellular matrix instability to cytoskeletal and nuclear signaling pathways, and (4) downstream ion-channel and gap-junction remodeling as secondary amplifiers. We outline the genetic architecture underlying these processes, focusing on established CTD-implicated genes in the TGF-β/SMAD pathway, valve and annulus regulators, cytoskeletal and myocyte-coupling proteins, and extracellular matrix components, while incorporating emerging CTD modifiers that expand the spectrum of arrhythmia susceptibility. Summary Recognition of CTDs as both vascular and electrical disorders reframes clinical management. Imaging markers such as mitral annular disjunction and diffuse fibrosis, together with targeted ambulatory rhythm monitoring and consideration of genetic context, may improve recognition of higher-risk phenotypes. Therapeutic strategies must balance arrhythmia control with procedural risk in fragile connective tissue substrates. Conclusions By unifying genetic, mechanistic, and clinical insights, this review provides an integrated framework for understanding arrhythmias in CTDs. It underscores the need for prospective registries and genotype-phenotype studies to refine surveillance and prevention strategies.
Global Burden of Elevated LDL-C

JAMA | July 29, 2026 | Volume: No volume available | Issue: No issue available | Pages: No page available

10.1001/jama.2026.8628 | PMID 42525403

Importance Elevated low-density lipoprotein cholesterol (LDL-C) is a modifiable risk factor for cardiovascular disease, the leading cause of premature death worldwide. Assessing the LDL-C–related burden is critical for guiding prevention and treatment strategies. Objectives To estimate the global, regional, and national burden of ischemic heart disease and ischemic stroke attributable to elevated LDL-C (relative to 35-54 mg/dL) from 1990 to 2023 and to quantify the contributions of population growth, aging, risk-deleted burden, and exposure changes to burden trends. Design, Setting, and Population This comparative risk assessment, part of the Global Burden of Disease Study 2023, estimated population-level LDL-C exposure and associated health loss in 204 countries and territories. Mean LDL-C levels were estimated using spatiotemporal gaussian process regression based on 806 studies across 161 countries. Relative risks were derived from meta-analyses of 38 randomized clinical trials. Population-attributable fractions for deaths and disability-adjusted life-years (DALYs) were estimated by age and sex for adults aged 25 years or older from 1990 to 2023, with 95% uncertainty intervals. Exposure Population-level LDL-C concentrations. Main Outcomes and Measures Population-attributable fractions, counts, and rates (all ages and age standardized per 100 000) of LDL-C–attributable deaths and DALYs from ischemic heart disease and ischemic stroke, with uncertainty intervals. Results In 2023, elevated LDL-C accounted for 3.6 million deaths (95% uncertainty interval, 2.2-5.4 million; 6.0% of global mortality) and 90.7 million DALYs (95% uncertainty interval, 58.9-123.3 million; 3.2% of DALYs). Although global all-ages rates remained stable, age-standardized death and DALY rates decreased by 45.6% and 39.5%, respectively, since 1990. In 2023, age-standardized LDL-C–attributable DALY rates were highest in Eastern Europe and lowest in high-income Asia-Pacific. One-third of the global LDL-C burden occurred in India and China. Population growth and aging drove the increasing burden, with notable regional disparities in LDL-C exposure and risk-deleted DALY rates shifting toward middle-sociodemographic settings. Conclusions and Relevance Despite declining age-standardized rates, the absolute LDL-C burden has increased since 1990 due to demographic changes and has shifted toward middle-sociodemographic countries. Measurement and surveillance gaps persist. Strengthened prevention, diagnosis, and treatment access strategies are essential to mitigate the health burden of LDL-C.
The Role of Multimodality Imaging in Guiding Ventricular Tachycardia Ablation: An Updated Review

Reviews in Cardiovascular Medicine | July 27, 2026 | Volume: 27 | Issue: 5 | Pages: No page available

10.31083/rcm47045 | PMID 42238643

Multimodality imaging plays a pivotal role in ventricular tachycardia (VT) ablation by providing critical insights into arrhythmogenic substrates and guiding procedural strategies. This updated review explores the integration of various imaging techniques, including echocardiography, cardiac magnetic resonance (CMR), multidetector computed tomography (MDCT), electroanatomical mapping (EAM), and nuclear imaging, to optimize VT ablation outcomes. Echocardiography, particularly transthoracic echocardiography (TTE), is an essential first-line tool for evaluating structural heart disease and left ventricular function. Moreover, echocardiography aids in risk stratification and procedural planning by detecting regional wall motion abnormalities and thrombus formation. Meanwhile, intracardiac echocardiography (ICE) enhances ablation precision by providing real-time catheter visualization, improving procedural success, and reducing complications such as cardiac tamponade. Nonetheless, CMR is the gold standard for myocardial tissue characterization, enabling the identification of scar burden and conduction channels critical for VT pathogenesis. Late gadolinium enhancement (LGE) facilitates preprocedural planning by localizing arrhythmogenic substrates, predicting VT recurrence risk, and informing ablation strategies. Additionally, T1- and T2-mapping techniques refine the assessment of myocardial fibrosis and inflammation, further improving patient selection and outcomes. MDCT complements CMR by offering high-resolution anatomical visualization and aids in delineating scar distribution, epicardial fat, and vascular structures, informing safe and effective ablation approaches. The integration of these imaging modalities significantly enhances VT ablation precision, reduces recurrence rates, and improves patient outcomes.
Prevalence and predictors of extra-aortic aneurysms in Marfan syndrome

Heart | May 12, 2026 | Volume: No volume available | Issue: No issue available | Pages: heartjnl-2025-327408

10.1136/heartjnl-2025-327408 | PMID 42103457

Background The prevalence and clinical correlates of extra-aortic vascular disease in Marfan syndrome remain incompletely defined, and current surveillance strategies primarily target the thoracic aorta. Methods We conducted a multicentre retrospective cohort study of 783 patients with Marfan syndrome across three tertiary centres, with systematic chart and imaging adjudication to define aneurysm and dissection distribution. Results Extra-aortic aneurysms were identified in 32% of patients, most commonly involving the iliac, carotid and subclavian arteries. Extra-aortic dissections occurred in 5.2%. Extra-aortic aneurysms clustered strongly with markers of advanced aortic disease, including abdominal aortic aneurysm (adjusted OR 3.48), prior aortic dissection (OR 3.39) and extra-aortic dissection (OR 4.44), as well as age >40 years and male sex. Genetic confirmation status was not associated with extra-aortic aneurysm presence. Conclusions Extra-aortic vascular involvement is common in Marfan syndrome and closely linked to advanced aortic pathology. These findings support risk-stratified vascular imaging beyond the thoracic aorta in higher-risk patients.
Optimal Timing of Coronary Artery Bypass Grafting in Patients with NSTEMI – A National Study from The United States

Marshall Journal of Medicine | May 1, 2026 | Volume: 12 | Issue: 2 | Pages: No page available

10.33470/2379-9536.1509

Background: The timing of coronary artery bypass grafting (CABG) in patients with non-ST-elevation myocardial infarction (NSTEMI) may critically impact clinical outcomes, yet the ideal surgical window remains unclear. We aimed to evaluate the association between time-to-CABG and in-hospital outcomes among NSTEMI admissions undergoing CABG. Methods: This retrospective cohort study utilized the US National Inpatient Sample database from 2017 to 2021 to evaluate the association between time-to-CABG and key in-hospital outcomes, including mortality, cardiac arrest, cardiogenic shock, ischemic stroke, acute kidney injury, and blood transfusion rates, while assessing length of stay (LOS) and hospital charges exclusively among survivors. Adult admissions with principal diagnosis of NSTEMI who underwent CABG without prior interhospital transfer were grouped by the calendar day of CABG from admission (0, 1, 2, 3, 4, 5, 6, and ≥7). Multivariate regression models were used to assess the outcomes across these eight groups. Results: Of 142,200 included admissions, same-day CABG (hospital day 0) was associated with the highest rates of in-hospital mortality, cardiac arrest, cardiogenic shock, and ischemic stroke. The adjusted odds of mortality, cardiac arrest, and cardiogenic shock were lower among admissions undergoing CABG between days 2 and 5. Likewise, the adjusted odds of ischemic stroke were lowest when CABG occurred on days 2 to 4. The odds of AKI increased when CABG was delayed beyond day 6, whereas blood transfusion rates showed no statistically significant association with time-to-CABG. Among survivors, LOS and hospital charges progressively increased with delayed CABGs. Conclusions: Among NSTEMI admissions undergoing CABG, CABG performed on hospital days 2 to 4 was associated with lower adjusted odds of several adverse in-hospital outcomes compared with same-day CABG. Further prospective studies are needed to validate these results and guide clinical decision-making.
Prognostic value of transaortic flow rate compared with ejection fraction and stroke volume index in low-gradient severe aortic stenosis

Heart | April 14, 2026 | Volume: No volume available | Issue: No issue available | Pages: heartjnl-2025-327594

10.1136/heartjnl-2025-327594 | PMID 41980805

Background In low-gradient severe aortic stenosis (AS), reduced left ventricular ejection fraction (LVEF <50%) is practically used to define low flow and prompt dobutamine stress echocardiography to discern pseudo-severe AS. In patients with preserved LVEF, stroke volume index (SVI) <35 mL/m² is typically used. However, both are volume-based surrogates. Transaortic flow rate (TAFR), calculated as stroke volume divided by left ventricular ejection time, may better reflect true flow. Nonetheless, comparative data between TAFR and established metrics remain limited. We aimed to evaluate the prognostic value of TAFR in symptomatic low-gradient severe AS. Methods We retrospectively identified patients with low-gradient severe AS (AVA ≤1 cm 2 and peak velocity (Vmax) <4 m/s or mean gradient (MG) <40 mm Hg) who underwent transcatheter aortic valve replacement at Mayo Clinic sites (2017–2023). The primary outcome was 1-year all-cause mortality. Survival was assessed using Kaplan-Meier and Cox proportional hazards models. Results Among 475 patients included (mean age 85±8 years; 49% women), 242 (51%) had TAFR <220 mL/s, 165 (35%) had EF <50%, and 221 (47%) had SVI <35 mL/m 2 . Low TAFR was significantly associated with higher 1-year mortality even after stratifying by EF or SVI. In multivariate analysis, TAFR was an independent predictor of mortality (HR 2.38; 95% CI 1.19 to 4.76, p=0.014) after adjusting for reduced LVEF, low SVI, gender, chronic kidney disease and mitral and tricuspid regurgitation. Conclusions In patients with symptomatic low-gradient severe AS, low TAFR, not SVI or LVEF, is independently associated with mortality and may offer more accurate measure of flow state for clinical staging.
Three-Dimensional Echocardiographic Evaluation of Rheumatic Tricuspid Valve Disease: A Prospective Single-Center Cohort Study

Reviews in Cardiovascular Medicine | March 31, 2026 | Volume: 27 | Issue: 3 | Pages: No page available

10.31083/rcm48678 | PMID 41923722

Background: Rheumatic heart disease (RHD) remains a prevalent cause of valvular heart pathology worldwide, especially in younger populations of low- and middle-income countries. Tricuspid valve (TV) involvement in RHD is usually secondary to left-sided valvular lesions and is often underdiagnosed, since two-dimensional echocardiography (2DE) has limited ability to visualize the complex tricuspid anatomy. Compared with 2DE, three-dimensional echocardiography (3DE) provides an en face visualization of the tricuspid valve, enabling direct planimetric measurements and detailed commissural assessment, and offers advantages for evaluating complex valvular heart disease (VHD). Thus, this study aimed to assess baseline characteristics and valvular morphology in patients with rheumatic tricuspid valve disease using 3DE. Methods: A prospective cohort single-center study conducted between April 2022 and April 2023 included 34 patients with rheumatic TV involvement. Baseline demographics, morphological features, and hemodynamic parameters were assessed using transthoracic 3DE. Results: The mean age of included patients was 45.5 ± 9.1 years, and 88.2% were female. Most patients had associated left-sided valvular involvement (mitral or combined mitral and aortic). Commissural fusion (50%), leaflet thickening (82.4%), restricted mobility (85.3%), and coaptation loss (58.8%) were predominantly noted. The mean diastolic TV gradient was 3.9 ± 3.4 mmHg, planimetry area 3.3 ± 1.7 cm2, and estimated pulmonary artery systolic pressure 43.3 ± 19.5 mmHg. Mean right ventricular (RV) global longitudinal strain was –23.6 ± 6.1%. Conclusion: Rheumatic TV involvement is characterized by commissural fusion, leaflet thickening, and coaptation loss, highlighting the diagnostic value of 3DE in identifying morphological patterns that may guide intervention planning.
Association of GLP-1 receptor agonists versus bariatric surgery with outcomes in obese patients with hypertrophic cardiomyopathy: a multicenter propensity-matched analysis

European Heart Journal - Quality of Care and Clinical Outcomes | March 26, 2026 | Volume: 12 | Issue: 5 | Pages: 731-739

10.1093/ehjqcco/qcag051 | PMID 41910632

Abstract Aims Obesity is linked with worse outcomes in hypertrophic cardiomyopathy (HCM). While both bariatric surgery (BS) and GLP-1 receptor agonists (GLP-1RA) promote weight loss and may improve cardiometabolic risk, their comparative outcomes in HCM remain unclear. Methods and results Adults with HCM and body mass index (BMI) ≥ 30 kg/m were divided into two cohorts: (i) GLP-1 RA users who never had BS, and (ii) BS patients who never received GLP-1 RA. Propensity score matching (1:1) was performed to balance demographics, comorbidities, and medications. Outcomes over 24 months include all-cause mortality, acute heart failure (HF) hospitalization, arrhythmias, change in BMI, and cardiovascular symptoms. Hazard ratios with 95% confidence intervals were estimated using Cox models. Of 5002 patients, 955 were included in each matched cohort after matching (mean age 54 ± 13 years, 70% female, BMI 40.0 kg/m). GLP-1 RA was associated with a significantly lower observed rate of all-cause mortality compared with BS (2.0% vs. 4.4%; HR 0.46; 95% CI 0.27–0.80; P = 0.004) and HF hospitalization (8.7% vs. 14.0%; HR 0.60; 95% CI 0.46–0.79; P &lt; 0.001). Similarly, GLP-1 RA use was associated with a lower incidence of composite cardiovascular outcomes (10.7% vs. 17.2%; HR 0.60; 95% CI 0.47–0.77; P &lt; 0.001). Rates of arrhythmia and cardiovascular symptoms were comparable between the two groups. BMI reduction was greater after bariatric surgery (−4.0 vs. −2.6 kg/m; P &lt; 0.001). Conclusion In obese patients with HCM, GLP-1 RA therapy was associated with lower all-cause mortality and fewer HF events compared with BS. Future studies are warranted to confirm our findings.
Glucagon-like Peptide-1 Receptor Agonists in Liver Transplant Recipients: A Retrospective Cohort Study

Transplantation Direct | March 23, 2026 | Volume: 12 | Issue: 4 | Pages: e1932

10.1097/txd.0000000000001932 | PMID 41884702

Background. Liver transplant recipients face high risks of cardiometabolic events after transplant, driven by posttransplant weight gain, diabetes, hypertension, as well as immunosuppression-related side effects. Glucagon-like peptide-1 receptor agonists (GLP1RAs) improve metabolic and cardiorenal outcomes in nontransplant populations, but their role in liver transplant recipients remains understudied. Methods. This retrospective cohort study used TriNetX data (January 2010–December 2023) to compare outcomes in liver transplant recipients prescribed GLP1RAs (semaglutide, dulaglutide, liraglutide) within 1-mo posttransplant (n = 546) versus nonusers (n = 37 153). Propensity score matching (1:1) balanced demographics, comorbidities, and medications (n = 541 per group). Outcomes included mortality, hospitalizations, cardiovascular/renal/respiratory events, and graft outcomes. Results. Over a mean follow-up 838.5 d (SD 291.9) in the GLP1RA cohort and 884.3 d (SD 313.7) in the non-GLP1RA group, GLP1RA use was associated with a 43% lower all-cause mortality (7.0% versus 12.9%; hazard ratio [HR], 0.566; 95% confidence interval [CI], 0.381-0.841) and 39% fewer hospitalizations (60.4% versus 74.5%; HR, 0.613; 95% CI, 0.530-0.710). Acute heart failure (HR, 0.386; 95% CI, 0.285-0.524), renal failure/dialysis (HR, 0.489; 95% CI, 0.413-0.579), and respiratory failure (HR, 0.484; 95% CI, 354-0.662) risks were significantly reduced. No differences were observed in graft failure/rejection, myocardial infarction, stroke, atrial fibrillation/flutter, ventricular tachycardia, or ischemic optic neuropathy. Conclusions. Early GLP1RA initiation in liver transplant recipients was associated with reduced mortality, hospitalizations, respiratory, and cardiorenal complications without compromising graft safety. These findings support GLP1RAs as a promising adjunct therapy, warranting prospective trials to confirm benefits in this high-risk population.
Meta-Analysis of the Diagnostic Accuracy of SVEAT, HEART, and TIMI Scores in Predicting Major Adverse Cardiac Events

Current Cardiology Reviews | March 20, 2026 | Volume: 22 | Issue: No issue available | Pages: No page available

10.2174/011573403x387322251203072735

aims: We assessed the diagnostic accuracy of the SVEAT score in predicting 30-day major adverse cardiac events (MACE) in comparison with the well-established HEART and TIMI scores. background: Acute chest pain (ACP) is a common symptom in emergency departments. Various risk stratification tools have been developed to assess patients presenting with ACP. The Simple Vascular Event Assessment Tool (SVEAT) is the most recent scoring system introduced, based on five variables: Symptoms of chest pain, history of Vascular disease, ECG, Age, and Troponin-I. objective: We assessed the diagnostic accuracy of the SVEAT score in predicting 30-day major adverse cardiac events (MACE) in comparison with the well-established HEART and TIMI scores. method: Following PRISMA guidelines, a systematic literature search was conducted across five databases until June 22, 2024. Four studies comprising 1,520 patients were included in this meta-analysis. The predictive accuracy of the SVEAT, HEART, and TIMI scores for 30-day MACE was assessed by the area under the receiver operating characteristic curve (AUC). Heterogeneity was evaluated using the I² statistic, with values over 75% indicating significant heterogeneity. Indirect comparisons among the scores were performed using the Z-test. result: Pooled AUC for the SVEAT score was 0.92 (95% CI: 0.86-0.98), indicating superior predictive accuracy compared to the HEART (AUC: 0.86, 95% CI: 0.81-0.92) and TIMI (AUC: 0.82, 95% CI: 0.69-0.96) scores. However, significant heterogeneity (I² = 90.6%) was observed across studies, potentially due to variations in patient demographics, clinical settings, and outcome definitions. Despite the higher AUC, indirect Z-test comparisons revealed no statistically significant differences between the scoring systems. conclusion: SVEAT score demonstrates potential as an accurate tool for predicting 30-day MACE in patients with ACP. other: N/A