Daily Cardiology Research Analysis

BACKGROUND AND AIMS: Atrial fibrillation-mediated cardiomyopathy (AFCM) represents an important reversible cause of left ventricular systolic dysfunction. Current clinical practice is indefinite heart failure (HF) pharmacotherapy despite left ventricular ejection fraction (LVEF) normalization. However, whether this is necessary to maintain normal LVEF, in addition to rhythm control, is uncertain. METHODS: This multi-centre, randomized trial conducted between 2021 and 2024 examined the impact of staged withdrawal of HF therapy following AF rhythm control and LVEF normalization in AFCM. Participants were randomized (1:1) to early withdrawal (Group A) or continued therapy for 6 months followed by delayed withdrawal (Group B), in a crossover design. The primary endpoint was the randomized comparison of cardiac magnetic resonance (CMR) LVEF maintenance ≥50% at 6 months, during which time Group A had withdrawn therapy and Group B remained on treatment. Secondary outcomes included cardiac remodelling, functional status, biomarkers, quality of life, and arrhythmia recurrence on vs off HF therapy. The total follow-up duration was 12 months. RESULTS: Between July 2021 and May 2024, 60 patients were enrolled (age 60 [55-65] years, previous persistent AF <1 year and maintaining sinus rhythm for minimum 6 months following AF rhythm control [catheter ablation in 97%]). All participants completed treatment withdrawal and 12-month follow-up. In the initial randomized comparison, LVEF was maintained ≥50% at 6 months in 90% of participants undergoing HF therapy withdrawal (Group A), compared with 100% who continued medical therapy (Group B) (odds ratio [OR] 1.18, 95% confidence interval [CI] 0.27-2.82, P = .47). CMR LVEF was similar between randomization groups at the end of the randomization phase (Group A: LVEF 58% [95% CI 54-60] vs Group B: LVEF 59% [95% CI 55-64], P = .236) and across study time points (mixed effects P = .37). Transthoracic echocardiography characteristics, N-terminal pro-B-type natriuretic peptide, functional status, quality of life and AF burden were similar on vs off HF therapy in the overall population. CONCLUSIONS: Withdrawal of HF therapy following AF rhythm control for prior AFCM and recovered LVEF was not associated with a decline in LVEF for most patients in the following 6 months.

BACKGROUND AND AIMS: Several randomized controlled trials (RCTs) have compared fractional flow reserve (FFR)-guided percutaneous coronary intervention (PCI) with angiography-guided PCI in different clinical settings, yielding mixed results. This individual patient data meta-analysis focused on trials where FFR was used to assess intermediate coronary lesions in chronic coronary syndrome (CCS) or non-culprit vessels in non-ST-elevation acute coronary syndromes (NSTE-ACS). METHODS: Randomized controlled trials comparing FFR- vs angiography-guided PCI with a minimum follow-up of 1 year were searched. Studies lacking angiographic inclusion criteria or using FFR for culprit arteries in NSTE-ACS were excluded. Studies including patients with ST-elevation myocardial infarction (MI) or undergoing surgical revascularization could be included after censoring these two subgroups. The primary outcome was the 1-year rate of major adverse cardiac events (MACE), defined as a composite of all-cause death, MI, and repeat revascularization. The secondary outcomes were a composite of all-cause death and MI, the individual components of the primary outcome, cardiac death, spontaneous MI, and procedural MI. The present study is registered with PROSPERO (CRD42024553676). RESULTS: Five RCTs were selected, including 2493 patients: 1241 in the angiography arm and 1252 in the FFR arm. More vessels underwent PCI in the angiography group (45.1% vs 30.2%, P < .001), with more stents implanted per patient [2.0 (2.0-3.0) vs 1.5 (1.0-2.0), P < .001]. One-year MACE occurred in 14.7% of patients in the angiography group and 12.1% in the FFR group [hazard ratio (HR) .80, 95% confidence interval (CI) .64-.99; P = .046]. The risk of MI was significantly reduced in the FFR-guided group (HR .71, 95% CI .53-.96; P = .031). These outcomes were driven by a reduction in peri-procedural MI with FFR guidance, with no significant difference between groups in non-procedural MI, MACE between 30 days and 1 year, and secondary outcomes. CONCLUSIONS: Fractional flow reserve-guided PCI was associated with reduced major adverse events in patients with CCS and NSTE-ACS due mainly to fewer peri-procedural MIs, with no differences in mortality or MACE beyond 30 days.

INTRODUCTION: Complete heart block (CHB) is a life-threatening condition that can lead to ventricular standstill, syncopal injury, and sudden cardiac death, and current electrocardiography (ECG)-based risk stratification (presence of bifascicular block) is crude and has limited performance. Artificial intelligence-enhanced electrocardiography (AI-ECG) has been shown to identify a broad spectrum of subclinical disease and may be useful for CHB. OBJECTIVE: To develop an AI-ECG risk estimator for CHB (AIRE-CHB) to predict incident CHB. DESIGN, SETTING, AND PARTICIPANTS: This cohort study was a development and external validation prognostic study conducted at Beth Israel Deaconess Medical Center and validated externally in the UK Biobank volunteer cohort. EXPOSURE: Electrocardiogram. MAIN OUTCOMES AND MEASURES: A new diagnosis of CHB more than 31 days after the ECG. AIRE-CHB uses a residual convolutional neural network architecture with a discrete-time survival loss function and was trained to predict incident CHB. RESULTS: The Beth Israel Deaconess Medical Center cohort included 1 163 401 ECGs from 189 539 patients. AIRE-CHB predicted incident CHB with a C index of 0.836 (95% CI, 0.819-0.534) and area under the receiver operating characteristics curve (AUROC) for incident CHB within 1 year of 0.889 (95% CI, 0.863-0.916). In comparison, the presence of bifascicular block had an AUROC of 0.594 (95% CI, 0.567-0.620). Participants in the high-risk quartile had an adjusted hazard ratio (aHR) of 11.6 (95% CI, 7.62-17.7; P < .001) for development of incident CHB compared with the low-risk group. In the UKB UK Biobank cohort of 50 641 ECGs from 189 539 patients, the C index for incident CHB prediction was 0.936 (95% CI, 0.900-0.972) and aHR, 7.17 (95% CI, 1.67-30.81; P < .001). CONCLUSIONS AND RELEVANCE: In this study, a first-of-its-kind deep learning model identified the risk of incident CHB. AIRE-CHB could be used in diverse settings to aid in decision-making for individuals with syncope or at risk of high-grade atrioventricular block.