Outcome of tailored therapy in rheumatic heart disease with persistent atrial fibrillation (RHD-AF).

INTRODUCTION: Rheumatic heart disease with persistent atrial fibrillation (RHD-AF) is associated with increased morbidity. However, there is no standardized approach for the maintenance of sinus rhythm (SR) in them. We aimed to determine the utility of a stepwise approach to achieve SR in RHD-AF. METHODS: Consecutive patients with RHD-AF from July 2021 to August 2023 formed the study cohort. The stepwise approach included pharmacological rhythm control and/or electrical cardioversion (Central illustration). In patients with recurrence, additional options included AF ablation or pace and ablate strategy with conduction system pacing or biventricular pacing. Clinical improvement, NT-proBNP, 6-Minute Walk Test (6MWT), heart failure (HF) hospitalizations, and thromboembolic complications were documented during follow-up. RESULTS: Eighty-three patients with RHD-AF (mean age 56.13 ± 9.51 years, women 72.28%) were included. Utilizing this approach, 43 (51.81%) achieved and maintained SR during the study period of 11.04 ± 7.14 months. These patients had improved functional class, lower NT-proBNP, better distance covered for 6MWT, and reduced HF hospitalizations. The duration of AF was shorter in patients who achieved SR, compared to those who remained in AF (3.15 ± 1.29 vs 6.93 ± 5.23, p = 0.041). Thirty-five percent (29) maintained SR after a single cardioversion over the study period. Only one underwent AF ablation. Of the 24 who underwent pace and ablate strategy, atrial lead was implanted in 22 (hybrid approach), and 50% of these achieved and maintained SR. Among these 24, none had HF hospitalizations, but patients who maintained SR had further improvement in clinical and functional parameters. CONCLUSIONS: RHD-AF patients who could achieve SR with a stepwise approach, had better clinical outcomes and lower HF hospitalizations.

Diastolic mitral regurgitation after dual chamber pacemaker.

First-degree Atrioventricular (AV) block can lead to symptoms of heart failure, due to AV dyssynchrony. We report a case of 40-year-old male with symptomatic 2:1 AV block with intermittent first-degree AV block who was implanted with dual chamber pacemaker with conduction system pacing (CSP). With conventional programming of managed ventricular pacing (MVP) and long AV delays, patient developed dyspnea due to diastolic mitral regurgitation because of AV dyssynchrony. Hence, AV delay optimization was done, and the patient became asymptomatic with atrial sensing and 100 % ventricular pacing. This report emphasizes the importance of AV delay optimization in CSP for symptomatic benefit.

Bilateral Cardiac Sympathetic Denervation for Refractory Multifocal Premature Ventricular Contractions in Patients With Nonischemic Cardiomyopathy.

BACKGROUND: Bilateral cardiac sympathetic denervation (BCSD) for refractory life-threatening ventricular arrhythmias is a neuromodulatory intervention targeting sympathetically driven focal or re-entrant ventricular arrhythmias. OBJECTIVES: This study sought to provide a more complete and successful option for intervention in patients in whom premature ventricular contraction (PVC) ablation is not feasible or has been unsuccessful. METHODS: A total of 43 patients with >5% PVC burden and concomitant nonischemic cardiomyopathy (NICM) who previously failed medical and ablation therapies were referred for BCSD. All patients underwent bilateral video-assisted thoracoscopic surgical approach with T1-T4 sympathectomy. Primary effectiveness endpoints were postprocedural PVC burden resolution, improvement in left ventricular ejection fraction (LVEF), and cessation of antiarrhythmic drugs (AADs). Safety endpoints included peri- and postprocedural complications. Outcomes were assessed over a 1-year follow-up period. RESULTS: Among the 43 patients who underwent BCSD, the mean age was 52.3 ± 14.7 years, 69.8% of whom were male patients. Presenting mean LVEF was 38.7% ± 7.8%, and PVC burden was 23.7% ± 9.9%. There were significant reductions in PVC burden postprocedurally (1.3% ± 1.1% post-BCSD, compared with 23.7% ± 9.9% pre-BCSD, P < 0.001) and improvements in LVEF (46.3% ± 9.5% post-BCSD, compared with 38.7% ± 7.8% pre-BCSD, P < 0.001). The rate of ICD therapies decreased from 81.4% (n = 35) to 11.6% (n = 5) (P < 0.001), leading to a significant reduction in use of AADs (100.0% to 11.6%, P < 0.001) and improvement in mean NYHA functional class (2.5 ± 0.5 to 1.4 ± 0.2, P < 0.001). Major intraoperative complications were seen in 4.7% of patients (hemothorax and chylothorax). Of the patients, 81.4% (n = 35) experienced no mortality or major complications over a 1-year follow-up period, with the remaining still within their first year postprocedure. CONCLUSIONS: BCSD is effective for the management of refractory PVCs and ventricular tachycardia who have failed previous ablation therapy.

Silent cerebral lesions following catheter ablation for atrial fibrillation: a state-of-the-art review.

Atrial fibrillation is associated with neurocognitive comorbidities such as stroke and dementia. Evidence suggests that rhythm control-especially if implemented early-may reduce the risk of cognitive decline. Catheter ablation is highly efficacious for restoring sinus rhythm in the setting of atrial fibrillation; however, ablation within the left atrium has been shown to result in MRI-detected silent cerebral lesions. In this state-of-the-art review article, we discuss the balance of risk between left atrial ablation and rhythm control. We highlight suggestions to lower the risk, as well as the evidence behind newer forms of ablation such as very high power short duration radiofrequency ablation and pulsed field ablation.

External irrigation of a non-irrigated ablation catheter for effective AV node ablation during conduction system pacing.

Ablation using non-irrigated catheter can lead to rapid rise in temperature of electrode tissue interface from tissue desiccation, steam and coagulum formation and this may limit power delivery and lesion size. We present a novel technique of external irrigation through the long sheath while using a non-irrigated ablation catheter during AV Node ablation and conduction system pacing. By bringing the long sheath closer to the tip of non-irrigated catheter and injecting cold normal saline allows cooling of electrode tissue interface leading to increase in power delivery resulting in a deeper lesion.

Risk of Adverse Outcomes Associated With Cardiac Sarcoidosis Diagnostic Schemes.

BACKGROUND: Multiple cardiac sarcoidosis (CS) diagnostic schemes have been published. OBJECTIVES: This study aims to evaluate the association of different CS diagnostic schemes with adverse outcomes. The diagnostic schemes evaluated were 1993, 2006, and 2017 Japanese criteria and the 2014 Heart Rhythm Society criteria. METHODS: Data were collected from the Cardiac Sarcoidosis Consortium, an international registry of CS patients. Outcome events were any of the following: all-cause mortality, left ventricular assist device placement, heart transplantation, and appropriate implantable cardioverter-defibrillator therapy. Logistic regression analysis evaluated the association of outcomes with each CS diagnostic scheme. RESULTS: A total of 587 subjects met the following criteria: 1993 Japanese (n = 310, 52.8%), 2006 Japanese (n = 312, 53.2%), 2014 Heart Rhythm Society (n = 480, 81.8%), and 2017 Japanese (n = 112, 19.1%). Patients who met the 1993 criteria were more likely to experience an event than patients who did not (n = 109 of 310, 35.2% vs n = 59 of 277, 21.3%; OR: 2.00; 95% CI: 1.38-2.90; P < 0.001). Similarly, patients who met the 2006 criteria were more likely to have an event than patients who did not (n = 116 of 312, 37.2% vs n = 52 of 275, 18.9%; OR: 2.54; 95% CI: 1.74-3.71; P < 0.001). There was no statistically significant association between the occurrence of an event and whether a patient met the 2014 or the 2017 criteria (OR: 1.39; 95% CI: 0.85-2.27; P = 0.18 or OR: 1.51; 95% CI: 0.97-2.33; P = 0.067, respectively). CONCLUSIONS: CS patients who met the 1993 and the 2006 criteria had higher odds of adverse clinical outcomes. Future research is needed to prospectively evaluate existing diagnostic schemes and develop new risk models for this complex disease.

Optimizing diastolic filling by pacing in nonobstructive hypertrophic cardiomyopathy.

BACKGROUND: Treatment options for symptomatic patients with nonobstructive hypertrophic cardiomyopathy (nHCM) are limited. OBJECTIVE: The purpose of this study was to determine the effect of sequential atrioventricular (AV) pacing, from different right ventricular (RV) sites with varying AV delays, on the diastolic function and functional capacity of patients with nHCM. METHODS: Twenty-one patients with symptomatic nHCM and normal left ventricular (LV) systolic function were prospectively enrolled. Inclusion criteria included PR interval >150 ms, E/e' ≥15, and an indication for implantable cardioverter-defibrillator (ICD) implantation. Doppler echocardiographic study was performed during dual-chamber pacing at various AV intervals. Pacing was performed at 3 RV sites: RV apex (RVA), RV midseptum (RVS), and RV outflow tract (RVO). The site and sensed AV delay (SAVD) at which optimal diastolic filling occurred were chosen based on diastolic filling period and E/e'. During ICD implantation, the RV lead was implanted at the site identified by the pacing study. Devices were programmed in DDD mode at the optimal SAVD. During follow-up, diastolic function and functional capacity were assessed. RESULTS: Among the 21 patients (age 47.8 ± 7.7 years; 81.0% male), baseline E/A and E/e' were 2.4 ± 0.6 and 17.2 ± 2.2, respectively. There was an improvement in diastolic function (E/e') in 18 patients (responders) when pacing from the RVA (12.9 ± 3.4; P <.001) than from the RVS (16.6 ± 2.3) and RVO (16.9 ± 2.2). Among responders, optimal diastolic filling occurred at SAVD of 130-160 ms with RVA pacing. Nonresponders had longer duration of symptoms (P = .006), lower LV ejection fraction (P = .037), and higher late gadolinium enhancement burden (P <.001). During 13.5 ± 1.5 months of follow-up, there was an improvement (Δ) in diastolic function (E/e' -4.1 ± 0.5), functional capacity (New York Heart Association functional class -1.5 ± 0.3), and reduction in N-terminal pro-brain natriuretic peptide level (-55.6 ± 12.3 pg/mL) compared to baseline. CONCLUSION: Pacing at an optimized AV delay from the RVA improves diastolic function and functional capacity in a subset of patients with nHCM.

Efficacy of SGLT2 Inhibitors in Patients With Diabetes and Nonobstructive Hypertrophic Cardiomyopathy.

The objective of this study was to evaluate the effects of sodium glucose co-transporter 2 inhibitors (SGLT2i) on functional capacity and diastolic function in patients with diabetes with nonobstructive hypertrophic cardiomyopathy (nHCM) and preserved left ventricular (LV) function. From January 2019 to October 2020, a prospective open-label study was performed on patients with type 2 diabetes mellitus and nHCM with New York Heart Association class II-III symptoms. Patients with a LV ejection fraction <50% were excluded. Patients were recruited from January 2019 to November 2019 to the SGLT2i arm and from November 2019 to October 2020 to the control arm. The primary composite end point was defined as achieving an improvement of at least 1.5 in E/e' and a reduction of ≥1 New York Heart Association functional class after 6 months of therapy. At baseline, there were no significant differences between the SGLT2i (n = 24) and control arms (n = 24). More patients in the SGLT2i arm achieved the primary end point than the patients in the control arm (70.8% vs 4.2%, p <0.001). After 6 months of therapy, patients in the SGLT2i arm showed a significant improvement in all diastolic function parameters (E/e' 16.3 ± 1.9 vs 13.3 ± 1.6, p <0.001; E/A 2.8 ± 0.1 vs 2.4 ± 0.1, p <0.001; left atrial volume 45.6 ± 5.2 vs 40.8 ± 4.9 ml/m2, p = 0.003). There was also an improvement in the 6-minute walk distance (295.1 ± 31.5 vs 343.0 ± 31.1 m, p <0.001) and N-terminal pro-B-type natriuretic peptide (481.4 ± 52.6 vs 440.9 ± 43.9 pg/ml, p <0.001) in patients who received SGLT2i. There was no significant change in the LV mass in the SGLT2i or control arm (-0.1 ± 0.3 vs 0.1 ± 0.5 g/m2, p = 0.319) after 6 months of therapy. A patient in the SGLT2i arm discontinued therapy because of a urinary tract infection. In conclusion, the use of SGLT2i improved diastolic function and functional capacity in patients with diabetes with nHCM and a preserved LV function.

Best Practices for the Catheter Ablation of Ventricular Arrhythmias.

Techniques for catheter ablation have evolved to effectively treat a range of ventricular arrhythmias. Pre-operative electrocardiographic and cardiac imaging data are very useful in understanding the arrhythmogenic substrate and can guide mapping and ablation. In this review, we focus on best practices for catheter ablation, with emphasis on tailoring ablation strategies, based on the presence or absence of structural heart disease, underlying clinical status, and hemodynamic stability of the ventricular arrhythmia. We discuss steps to make ablation safe and prevent complications, and techniques to improve the efficacy of ablation, including optimal use of electroanatomical mapping algorithms, energy delivery, intracardiac echocardiography, and selective use of mechanical circulatory support.

Catheter Ablation for Ventricular Arrhythmias in Hypertrophic Cardiomyopathy.

Implantable cardioverter-defibrillators are the mainstay of therapy for prevention of sudden cardiac death in high-risk patients with hypertrophic cardiomyopathy (HCM). Catheter ablation is a useful option for patients with recurrent, drug refractory monomorphic ventricular tachycardia (VT), and device therapy. Compared with other nonischemic substrates, there are limited data on the role and outcomes of catheter ablation in HCM. The challenges of VT ablation in HCM patients include deep intramural and epicardial substrates, suboptimal power delivery, and higher recurrence due to progression of disease. Patient selection, using cardiac MRI scar localization, and optimizing ablation techniques can improve outcomes in these patients.

Ventricular Tachycardia in Granulomatous Myocarditis: Role of Catheter Ablation.

Granulomatous myocarditis is an inflammatory disease of the myocardium, characterized by lymphocytic infiltration with characteristic granuloma formation. Although a host of disease processes can elicit myocardial granulomas, two common entities are cardiac sarcoidosis and cardiac tuberculosis. Cardiac arrhythmias in this condition are frequent and management of ventricular arrhythmias can be challenging, especially in those with drug-refractory ventricular tachycardia and electrical storm. In this review, we highlight the role of catheter ablation for ventricular tachycardia and optimal patient selection for catheter ablation, based on cardiac imaging.

Suspecting and diagnosing transthyretin amyloid cardiomyopathy (ATTR-CM) in India: An Indian expert consensus.

Transthyretin cardiac amyloidosis (ATTR-CM) is a rare and under-recognized disorder characterized by the aggregation of transthyretin-derived insoluble amyloid fibrils in the myocardium. Heterogeneity of symptoms at presentation, makes its diagnosis often delayed. An expert panel gathered on a virtual platform across India to conduct a meeting for developing a guiding tool for ATTR-CM diagnosis. The panel recommended younger age (≥40 years) for suspecting ATTR-CM and thick-walled non-dilated hypokinetic ventricle was considered as one of the important red flags. Electrocardiogram (ECG) and echocardiography (ECHO) findings were recommended as primary tests to raise the suspicion while nuclear scintigraphy and hematological tests were recommended to confirm the diagnosis and rule out amyloid light-chain (AL) amyloidosis. Cardiac magnetic resonance (CMR) and biopsy were recommended in case of ambiguity in the presence of red flags. Considering the lack of expert guidelines in the Indian scenario, a standardized diagnostic algorithm was also proposed.

Interventions in the diagnosis and adoption of pacemaker therapy in sinus node dysfunction patients: Results from the IMPROVE Brady study.

AIMS: IMPROVE Brady assessed whether a process improvement intervention could increase adoption of guideline-based therapy in sinus node dysfunction (SND) patients. METHODS: /Results: IMPROVE Brady was a sequential, prospective, quality improvement initiative conducted in India and Bangladesh. Patients with symptomatic bradycardia were enrolled. In Phase I, physicians assessed and treated patients per standard care. Phase II began after implementing educational materials for physicians and patients. Primary objectives were to evaluate the impact of the intervention on SND diagnosis and pacemaker (PPM) implant. SF-12 quality of life (QoL) and Zarit burden surveys were collected pre- and post-PPM implant. A total of 978 patients were enrolled (57.7 ± 14.8 years, 75% male), 508 in Phase I and 470 in Phase II. The diagnosis of SND and implantation of PPM increased significantly from Phase I to Phase II (72% vs. 87%, P < 0.001 and 17% vs. 32%, P < 0.001, respectively). Pacemaker implantation was not feasible in 41% of patients due to insurance/cost barriers which was unaltered by the intervention. Both patient QoL and caregiver burden improved at 6-months post-PPM implant (P < 0.001). CONCLUSIONS: A process improvement initiative conducted at centers across India and Bangladesh significantly increased the diagnosis of SND and subsequent treatment with PPM therapy despite the socio-economic constraints.