Heart failure and the risk of left atrial thrombus formation in patients with atrial fibrillation and atrial flutter: insights from the LATTEE registry

The aim of the study was to evaluate the prevalence of left atrial thrombus (LAT) on transesophageal echocardiography (TEE) in patients with atrial fibrillation and atrial flutter (AF/AFl) with reference to the presence of heart failure (HF) and its subtypes.

The research is a substudy of multicenter, prospective, observational Left Atrial Thrombus on Transesopahgeal Echocardiography (LATTEE) registry, which comprised 3109 consecutive patients with AF/AFl undergoing TEE prior to direct current cardioversion or catheter ablation. TEE parameters, including presence of LAT, were compared between patients with and without HF, as well as different subtypes of HF, including HF with preserved (HFpEF), mid-range (HFmrEF) and reduced ejection fraction (HFrEF).

HF was diagnosed in 1336 patients (43%). HF patients had higher prevalence of LAT than non-HF patients (12.8% vs. 4.4%, P<0.001). The rate of LAT increased with the more advanced type of systolic dysfunction (HFrEF vs. HFmrEF vs. HFpEF: 20.3% vs. 10.5% vs. 7.4%, P<0.001; Figure 1). Univariate analysis revealed that HFrEF (OR 4.13, 95% CI: 3.13–5.46) but not HFmrEF or HFpEF predicted the presence of LAT. Multivariable logistic regression indicated that left ventricular ejection fraction (unit OR=0.94 per 1%, 95% CI: 0.93–0.95) was an independent predictor of LAT formation. Receiver operator characteristic analysis showed LVEF ≤48% predicted presence of LAT (AUC=0.74, P<0.0001).

The diagnosis of HFrEF, but not HFpEF, confers a considerable risk of LAT presence despite widespread utilization of adequate anticoagulation in the assessed population. TEE should be considered in these patients prior to cardioversion or catheter ablation despite adequate oral anticoagulation.

Type of funding sources: None.