Several abstracts at Heart Rhythm 2024, held May 16-19 in Boston, MA, featured data from the NCDR suite of registries. Research covered topics such as outcomes for pediatric subcutaneous ICD implantation; procedural success rates and risk factors associated with catheter ablation for atrial tachyarrhythmias; comparing echocardiographic guidance during left atrial appendage occlusion (LAAO); and atrial fibrillation (AFib) ablation in patients with heart failure with reduced ejection fraction (HFrEF).

Explore main findings from the abstracts below. For more details, search for the abstracts on the meeting page here.

Characteristics and Outcomes of Pediatric Patients Undergoing Subcutaneous ICD Implantation
Acute procedural complications were rare among pediatric patients undergoing subcutaneous ICD implantation, with rates of major adverse events or any adverse events comparable to pediatric transvenous ICD implantation or adult subcutaneous ICD implantation, according to an abstract using data from the ACC’s EP Device Implant Registry. Scott J. Weinreb, MD, et al., included 595,467 ICD implants (66% men, mean age 17.7 years) from 2016-2021. Although there was no significant difference in major adverse events and any adverse events when comparing pediatric subcutaneous ICD to an adult cohort (n=21,814), incidence of lead dislodgement was greater in the pediatric group (0.6% vs. 0.2%, p=0.03).

Outcomes of Catheter Ablation For Atrial Tachyarrhythmias in CHD

Acute success rates range from 71% to 81% for catheter ablation of atrial tachyarrhythmia substrates in patients with congenital heart disease (CHD) captured by the ACC’s IMPACT Registry. Chandra Srinivasan, MD, et al., included 1,350 cases from 82 centers with 69% categorized as biventricular repair without atrial baffling (BVR), 13% as biventricular repair with atrial baffling (BVAB) and 18% as single ventricle post-Fontan (SVF). Prior catheter ablation therapy, multiple targets, non-cavotricuspid isthmus substrate, SVF and BVAB vs. BVR were all factors associated with lower likelihood of procedural success.

Comparison of 3D Intra-Cardiac Echocardiography vs. Transesophageal Echocardiography in LAAO
Success and complication rates of 3D intra-cardiac echocardiography (ICE) to guide LAAO vs. transesophageal echocardiography (TEE) are comparable, with use of 3D ICE resulting in significantly lower physician resource utilization time with the tradeoff of longer procedure time. Auroa Badin, MD, FACC, et al., looked at records from the ACC’s LAAO Registry at Riverside Methodist Hospital between March 2019 and April 2022, including a total of 69 patients (77 ± 8 years, 64% men, left ventricular ejection fraction [LVEF] 55 ± 11%, CHA₂DS₂-VASc Score 4 [3-5]) undergoing LAAO – 24 with 3D ICE and 45 with TEE guidance – in their analysis.

Catheter Ablation For AFib in Patients With HFrEF

Catheter ablation for AFib in patients with HFrEF is not commonly performed when compared to patients with LVEF ≥40%, and this trend has remained consistent from 2018 through 2022, according to a retrospective analysis looking at data from ACC’s AFib Ablation Registry. Mutaz Alkalbani, MD, et al., included 80,710 patients undergoing catheter ablation for AFib – 70,878 patients had LVEF ≥40% and 9,832 patients had HFrEF. When comparing the two groups, they found that HFrEF patients had more comorbidities, including valvular disease, coronary disease, hypertension, diabetes and stroke, were more likely to have an adjunctive ablation beyond pulmonary vein isolation, and scored lower on the AFib effect on quality-of-life questionnaire.