Findings from several studies presented at ESC Heart Failure Congress 2026 in Barcelona, Spain, were simultaneously published in JACC and JACC: Heart Failure, covering topics like arrhythmic burden in cardiac amyloidosis (CA), stroke and bleeding risk in CA, and survival among patients undergoing left ventricular assist device (LVAD) implantation vs. heart transplantation.

In the prospective EXCALIBUR study, seeking to characterize arrhythmic burden among patients with differing subtypes of CA, Adam Ioannou, MBBS, et al., found that clinically significant arrythmias were common and often asymptomatic.

In total, 110 patients with a new diagnosis of either transthyretin amyloid cardiomyopathy (ATTR-CM) or light-chain CA (AL-CA) were included. They underwent comprehensive phenotyping with cardiac magnetic resonance and then received an implantable loop recorder.

Results showed that 17.3% of patients experienced bradyarrhythmias with a Class I indication for pacemaker implantation. This event was seen more in the ATTR-CM group (23.8%) than the AL-CA group (8.5%; p=0.036). The authors describe an association between baseline conduction abnormalities as well as higher myocardial amyloid burden with bradyarrhythmic events.

New atrial fibrillation (AFib) was noted in 28.2% of patients and was again more likely among patients with ATTR-CM (50% vs. 12.2%, p<0.001). Additionally, higher amyloid burden was associated with a greater likelihood of AFib.

"This prospective and systematic approach is particularly important, as the majority of arrhythmic events were asymptomatic and would otherwise have remained undetected, highlighting the substantial subclinical burden of rhythm disturbance in this population," write the authors.

Another study explores stroke and bleeding risk among patients with CA, using data from Danish nationwide registries. Navid Noory, MD, et al., identified an association between CA and long-term risk of bleeding-related hospitalization, but not with long-term stroke risk.

They included 735 patients with CA and 2,205 matched controls (median age 79 years, 75% men) with a five-year follow up.

Overall, patients with CA did not have a higher risk of stroke (adjusted hazard ratio [aHR], 1.10; 95% CI, 0.67-1.81). Bleeding-related hospitalization was observed more frequently in patients with CA (21.4% vs. 15.8%; Gray test p=0.0029), resulting in a higher bleeding risk (aHR, 2.09; 95% CI, 1.65-2.64). Gastrointestinal bleeding was the most common type of bleeding complication among those with CA. In the control group, the most common bleeding type was hematuria.

All-cause mortality was also higher among the CA group (aHR, 2.99; 95% CI, 2.60-3.44), and results were consistent among patients with AFib.

"These findings support a more individualized antithrombotic strategy in CA, balancing the uncertain long-term risk of thromboembolism against a consistently increased bleeding risk," note the authors. "Future studies should identify clinical, imaging, and biomarker-defined subgroups in whom the net benefit of anticoagulation is greatest."

Another publication reports survival and adverse events among middle-aged and older patients with advanced heart failure (HF) treated via the HeartMate 3 LVAD or heart transplantation.

Nir Uriel, MD, FACC, et al., looked at 1,763 patients from the MOMENTUM 3 cohort and 5,336 patients from the UNOS registry, comparing two-year survival from treatment or listing as well as one-year major adverse events.

After propensity score matching, heart transplantation saw higher two-year survival from treatment for both middle-aged (90.7% vs. 83.8%; HR, 1.76; p=0.0004) and older patients (87.5% vs. 77.7%; HR, 1.89; p<0.0001).

When incorporating the waitlist period, survival among the LVAD treatment group was higher vs. survival free from delisting due to deterioration in middle-aged heart transplant candidates (83.0% vs. 75.0%, HR 0.62, p<0.0001) and numerically higher among the older patient group (76.6% vs. 72.2%; HR 0.81; p=0.064).

"[Adverse event] profiles differed between therapies, with higher infection-related hospitalization after [heart transplantation], higher stroke rates among LVAD recipients in older adults, and similar rates of renal dysfunction requiring dialysis between therapies," add the investigators.