Habib, Eiad

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.

Background: AF in the setting of cardiac amyloidosis is associated with a high risk of TEs, irrespective of CHA2DS2-VASc score. While warfarin has been the traditional anticoagulant, DOACs offer a promising alternative, but their safety in this population remains underexplored. This study aimed to evaluate the prevalence of thromboembolic events (TEs), including stroke and transient ischemic attack (TIA), and major bleeding events in patients with cardiac amyloidosis (CA) and atrial fibrillation (AF) treated with either warfarin or direct oral anticoagulants (DOACs). Additionally, we aimed to explore whether DOACs are at least as effective as warfarin in protecting against TEs in this population. Methods: This retrospective cohort study analyzed 422 patients with confirmed CA and AF from Mayo Clinic, with a median follow-up of 4.3 years. Data on anticoagulation therapy, baseline characteristics, and outcomes (TEs and bleeding) were collected. Statistical analyses included chi-square tests, t-tests, and Cox regression to assess the relationship between anticoagulation and TE. Results: Among 422 patients, 21 experienced a TE. The annual event rate was 0.83% for warfarin and 0.67% for DOACs, with no significant difference (HR 0.66, CI 0.22–2.01, p = 0.5). Patients with anticoagulation interruptions > 5 days had increased TE risk (HR 3.19, CI 0.97–10.5, p = 0.056). The bleeding rate was 9.9% over 4.3 years (2.33% per year), with no significant differences between anticoagulants. Conclusions: Both warfarin and DOACs have similar, low risks of TEs in CA and AF patients. However, anticoagulation interruptions were associated with increased TE risk, emphasizing the challenges in managing anticoagulation in this population.

Abstract Introduction/Background Transthyretin amyloidosis (ATTR) is a debilitating disease that leads to progressive cardiac dysfunction. Tafamidis is the gold standard therapy for ATTR cardiomyopathy. In recent observational studies, sodium-glucose cotransporter-2 inhibitors (SGLT2-Is) have demonstrated cardiovascular benefits in ATTR cardiomyopathy, but their role in ATTR cardiomyopathy as combination therapy with tafamidis remains unclear. Purpose To investigate the impact of combination therapy with tafamidis and SGLT2-Is versus just tafamidis in patients with known ATTR cardiomyopathy. Methods This retrospective cohort study utilized data from the TriNetX multinational database. Patients diagnosed with ATTR cardiomyopathy who received tafamidis were identified and stratified into two cohorts based on SGLT2-I use. Outcomes were assessed over three years, including all-cause mortality, all-cause hospitalizations, acute myocardial infarction (AMI), acute heart failure (HF) hospitalizations, ischemic stroke, atrial fibrillation/flutter, end-stage renal disease (ESRD) or requirement for renal replacement therapy, and ventricular tachycardia. Propensity score matching was used to balance both cohorts based on clinical comorbidities, medication use, and laboratory data. Adjusted odds ratios (OR) were calculated by logistic regression models. Results After propensity score matching, 409 patients were included in each cohort with a follow-up duration of 722 days (SD 320.87) for the SGLT2-I cohort and and 755.90 days (SD 363.26) for the non-SGLT2-I cohort. SGLT2-Is were associated with significantly lower rates of all-cause hospitalizations (41.1% vs. 50.9%; OR 0.67 [p = 0.005]) and AMI (6.6% vs. 13.9%, OR 0.44 [p = 0.001]), which persisted by three years (all-cause hospitalizations: 52.1% vs. 61.4%, OR 0.67 [p = 0.006] and myocardial infarction: 11.2% vs. 18.3%, OR 0.56 [p = 0.004]). No significant differences among the two cohorts were observed for all-cause mortality, acute HF hospitalizations, ischemic stroke, atrial fibrillation/flutter, ventricular tachycardia, or ESRD/need for renal replacement therapy. Conclusions SGLT2-Is, in combination with tafamidis, are associated with decreased all-cause hospitalizations and AMI in ATTR cardiomyopathy. While a mortality benefit was not demonstrated, these results depict the magnitude of clinical benefit derived from combination therapy with tafamidis and SGLT2-Is as opposed to prior observational studies which investigated SGLT2-I single therapy

Abstract Background/Introduction Patients with transthyretin cardiac amyloidosis (ATTR-CA) and atrial fibrillation (AF) have increased risk for left atrial thrombi, necessitating anticoagulation therapy if bleeding risk is not prohibitive. Limited data is available comparing the use of direct oral anticoagulants (DOACs) to warfarin in this population. Purpose To evaluate and compare clinical efficacy and safety outcomes of DOACs versus warfarin in patients with ATTR-CA and AF. Methods We conducted a retrospective cohort study using the TriNetX Network, which includes data from over 140 million patients, between 2014 and 2022. Adults (aged ≥18 years) with ATTR-CA and AF were identified. These patients were further categorized into two groups: one cohort which utilized DOACs for oral anticoagulation and the other cohort on warfarin. 1:1 propensity score matching (PSM) was utilized to balance baseline characteristics between the two cohorts. The primary outcome was rate of stroke, with secondary outcomes including all-cause death, all-cause hospitalizations, and acute heart failure exacerbations. Safety outcomes included intracranial hemorrhage, gastrointestinal hemorrhage, and hematuria. Adjusted odds ratios (aORs) with 95% confidence intervals (CIs) were calculated. Results Among 8,214 adults with ATTR-CA and AF, 5,774 patients were on a DOAC while 2,440 patients were on warfarin. After PSM, 2,425 patients were included in each group. The use of DOACs for AF in patients with ATTR-CA was associated with a significantly lower risk of ischemic stroke compared to warfarin (5.7% versus 7.3%, aOR 0.771 [95% CI, 0.612-0.971]) by the end of the one year follow up. There were no differences in all-cause mortality (19.8% versus 21%, aOR 0.927 [95% CI, 0.806-1.066]), all-cause hospitalizations (19.2% versus 21.6%, aOR 0.863 [95% CI, 0.624-1.195]) or heart failure exacerbations (43.6% versus 46%, aOR 0.906 [95% CI, 0.809-1.015]). Safety outcomes favored DOACs over warfarin, with a lower risk of intracranial hemorrhage (4.5% versus 7.8%, aOR 0.565 [95% CI, 0.444-0.720]), and comparable rates of GI hemorrhage and hematuria. Conclusions DOACs may be safely used in ATTR-CA patients with AF, offering a lower risk of stroke compared to warfarin and a more favorable safety profile. These findings emphasize the potential advantages of DOACs in this population and underline the need for prospective studies to validate these results.

Abstract Background Emerging evidence suggests that premature ventricular contractions (PVCs) may influence atrial electrophysiology and remodeling, potentially leading to higher rates of atrial fibrillation (AF) recurrence. However, existing data is limited to small-scale studies. Therefore, we conducted a retrospective study to evaluate the potential association between PVCs and AF ablation outcomes, which may suggest the need for more aggressive management of ventricular ectopy in this population. Objective This study aims to assess the 5-year outcomes of catheter ablation for AF in patients with and without a diagnosis of PVCs. Methods Using the TriNetX Analytics Research Network, we included patients aged ≥ 18 years who underwent AF catheter between January 1, 2014, and January 1, 2020. Patients were further categorized into two groups based on the presence of a diagnosis of PVCs. Propensity score matching (PSM) was performed using patient demographics, left ventricular ejection fraction (LVEF), cardiac comorbidities, and medications. Study outcomes included all-cause mortality & hospitalization, acute heart failure (HF), and rhythm control interventions during a 5-year follow-up. Results A total of 15,987 patients with PVCs and 40,605 patients without PVCs were identified. After PSM, 15,152 patients from each group were included for further analysis. Compared to control group, patients with PVCs had significantly higher odds of all-cause mortality (odds ratio [OR], 1.138; 95% confidence interval [CI], 1.034–1.253), all-cause hospitalization (OR, 1.300; 95% CI, 1.243–1.360), acute heart failure (HF) (OR, 1.223; 95% CI, 1.162–1.287), and cardiogenic shock (OR, 2.059; 95% CI, 1.751–2.420) following catheter ablation for AF at 5-year follow-up. Additionally, higher odds of AF requiring cardioversion (OR, 1.135; 95% CI, 1.074–1.199) or repeated ablation (OR, 1.164; 95% CI, 1.085–1.249) were observed in the PVCs group. Conclusion Premature ventricular contractions were associated with poorer clinical outcomes and a higher odds of requiring additional rhythm control intervention following catheter ablation for AF. These findings suggest that PVCs may be a marker for worse outcomes after AF ablation.

ABSTRACT Background Cardiac amyloidosis (CA) is frequently complicated by atrial fibrillation (AF), yet outcomes after left atrial appendage occlusion (LAAO) in this population remain poorly defined. Methods We conducted a retrospective TriNetX study of adults with AF undergoing LAAO, comparing patients with and without CA after 1:1 propensity matching. Outcomes were assessed using Kaplan–Meier analyses and Cox regression. Results Among 532 matched pairs, mortality and major adverse cardiovascular events were similar between groups, whereas major bleeding was higher in CA (HR 1.90). Conclusions LAAO yields comparable ischemic outcomes in CA, though bleeding risk is increased.

Ventricular arrhythmias after electrical cardioversion for AF are rare. Most of these arrhythmias are related to QT prolongation, resulting from marked and sudden slowing of heart rates, treatment with Class III antiarrhythmic drugs or other QT-prolonging medications, and the ventricular repolarisation remodelling effect of electrical cardioversion. A case of polymorphic ventricular tachycardia post-cardioversion of rapid AF in a patient with tachycardia-induced cardiomyopathy and the use of amiodarone is reported.

Background: Left atrial (LA) strain is a marker of atrial myopathy and remodeling. While echocardiographic LA strain is increasingly used to assess atrial function, the prognostic value of change in LA strain before and after catheter ablation (CA) for atrial fibrillation (AF) remains underexplored. Objective: To evaluate the association between quartiles of LA strain parameters—including pre-ablation strain, post-ablation strain, and change in strain—with atrial fibrillation recurrence, stratified by ejection fraction (EF). Methods: This retrospective study encompassed AF patients who underwent their first CA at Mayo Clinic Arizona from Oct 2018 to Feb 2022. Transthoracic echocardiography parameters, including the three LA strain (LAS) phases—contraction, conduit, and reservoir—were collected using TOMTEC software on the closest date before the CA procedure. Logistic regression analysis was used to evaluate the association between LAS parameters and AF recurrence post-CA, adjusted for clinical covariates including age, gender, hypertension, diabetes, coronary artery disease, dyslipidemia, obstructive sleep apnea, thromboembolism, TIA/stroke, chronic kidney disease, and AF type. Results: Out of 335 patients who underwent CA, 222 had both pre- and post-ablation LA strain data. Among these, 71 of 222 patients (31.98%) experienced AF recurrence after CA. The mean age at time of procedure was 66.9 ± 10.3 years; 150 (67.57%) were male, and 83 (37.39%) had persistent AF. Significant associations were observed between specific quartiles of LA strain and AF recurrence. In patients with EF >50%, Q4 of contraction strain change (pre- vs. post-ablation) was strongly associated with increased recurrence risk (OR 8.80; 95% CI 1.80–42.98). Similarly, post-ablation contraction strain Q4 was associated with higher recurrence in both the overall group (OR 6.36; 95% CI 1.47–27.53) and the EF>50% subgroup (OR 8.80; 95% CI 1.80–42.98). In contrast, reservoir strain change Q2 (OR 0.10; 95% CI 0.01–0.86), and post-ablation reservoir strain Q3 (OR 0.09; 95% CI 0.01–0.69) and Q4 (OR 0.10; 95% CI 0.02–0.70) were protective. Conclusions: Greater increases in contraction strain post-ablation and higher post-ablation contraction strain were strongly associated with AF recurrence, particularly in those with preserved EF. Conversely, favorable reservoir strain post-ablation was protective. LA strain may offer key prognostic value in risk-stratifying AF patients undergoing ablation.

Introduction: Complex congenital heart disease (CHD) patients with atrial arrhythmias have higher rates of morbidity and mortality compared to less complex CHD patients. This study aims to identify echocardiographic predictors of thromboembolism (TE) and major bleeding in patients with Tetralogy of Fallot (ToF) or Pulmonary Atresia with Intact Ventricular Septum (PA-IVS) and atrial fibrillation or flutter (AF). Methods: This cohort study included patients with ToF or PA-IVS who had a diagnosis of AF who underwent a TTE across three sites. Outcomes were incidence rate of major bleeding or TE, calculated using univariable and multivariable cox regression with interaction for anticoagulant choice and fractional area change (FAC). The HAS-BLED score was augmented with major predictors of bleeding, and receiver operator curves compared. Results: We included 300 patients (287 ToF [95.7%], 13 PA-IVS [4.3%]), mean age 45.6 years. Most received warfarin (227 [79.4%]), 40 (13%) used DOACs, and 5 (1.6%) used enoxaparin. TTE predictors of TE included large LVOT diameter ≥3cm (HR 8.92, p=0.002), small LVOT VTI (p=0.014), FAC <30% (HR 7.08, p=0.026) and moderate RV dysfunction (HR 10.75, p=0.026). Predictors of major bleeding included moderate tricuspid regurgitation (HR 2.40, p=0.022), right atrial pressure (1.12, p<0.001), severe RA enlargement (HR 2.30, p=0.048), RV mid diameter (HR 1.06, p=0.005), RV end diastolic area (HR 1.04, p=0.021), RV end systolic area (HR 1.05, p=0.016) elevated RVSP and FAC ≤45% (HR 0.37, p=0.016). Among warfarin users, impaired RV function (FAC ≤45%) was linked to reduced major bleeding events (HR 0.27, p=0.025). There was a nonsignificant trend towards higher bleeding in DOAC users with FAC >45% (HR 3.87, p=0.284), but significantly higher bleeding in DOAC users with FAC ≤45% (HR 12.41, p=0.008) vs. warfarin users with normal RV function (table 1). We developed an augmented HAS-BLED score: the standard score plus one point for moderate-to-severe pulmonic or tricuspid regurgitation and one for FAC ≤45%. This outperformed the standard HAS-BLED in predicting major bleeding (AUC 0.67 augmented vs. 0.57 un-augmented, p=0.008) (figure 1). Conclusion: Echocardiographic evidence of right heart disease is a strong predictor of major bleeding in patients with ToF or PA-IVS. FAC is a useful tool to determine excess major bleeding risk, particularly in DOAC users. Augmenting HAS-BLED with right heart parameters improves diagnostic accuracy.