LAUSR

To evaluate the proportion of patients in whom parameters that define the diagnosis of HFpEF and HFmrEF persist versus normalize upon elimination of AF. Atrial fibrillation (AF) and heart failure with preserved or mid-range ejection fraction (HFpEF or HFmrEF) concur in many patients. Distinction between these two diagnoses remains challenging as one can cause or exacerbate the other. Adequate patient selection for invasive AF treatment is crucial to improve rhythm outcome. Patients underwent thoracoscopic ablation, consisting of pulmonary vein isolation (PVI) alone or PVI with additional lines in the case of persistent AF. Patients were prospectively followed-up. HFmrEF or HFpEF was defined as left ventricular ejection fraction (LVEF) ≥40% or ≥50% respectively and N-terminal prohormone of brain natriuretic peptide (NT-proBNP) levels >125 pg/ml. Patients who remained free from AF, or any atrial tachycardia of more than 30 seconds, at 6 months postoperatively, were included in this study. Patients with AF recurrences during this period were excluded. The primary outcome was the change of NT-proBNP at 6 month follow-up. From 2008 to 2017, 92 patients undergoing thoracoscopic AF ablation fulfilled the aforementioned criteria and were included. Of these patients, mean age was 61±8 years and 66 (72%) were male. Median NT-proBNP was 366 pg/ml (128–2916) and mean LVEF was 53±7%. Thirty (35%) patients had a LVEF of 40–49%. Six months after elimination of AF, NT-proBNP was <125 pg/ml (Figure 1A: median 87 (50–122) vs 459 (137 – 2916) pg/ml at baseline; p<0.001) in 26 patients (28%), whereas in the remaining patients NT-proBNP was unchanged (Figure 1B: median 298 (126–1568) vs. 318 (128–2387) pg/ml at baseline; p=0.011). Figure 1. NT-proBNP alterations after thoracoscopic AF ablation from baseline to 6 month follow-up. A. Patients with normalization of NT-proBNP. B. Patients with unchanged high levels of NT-proBNP. In 28% of patients the diagnostic criteria of HFpEF/HFmrEF are caused by AF and normalize upon elimination of AF with thoracoscopic ablation.