Determining The Risk of Atrial Fibrillation Paroxysm in Patients With Chronic Heart Failure With Intact and Reduced Ejection Fraction.

Aim: To determine predictors for the development of atrial fibrillation (AF) in patients with chronic heart failure (CHF) with preserved and reduced ejection fraction by echocardiography (EchoCG) according to an extended protocol with determination of diastolic function and left atrial global strain.

Material And Methods: Data of 168 patients with stage I-III CHF without a history of AF were analyzed. All patients underwent echocardiography according to an extended protocol with the determination of diastolic dysfunction (DD), left atrial ejection fraction (LA EF), and left atrial global strain (LA GS). Tissue Doppler imaging (TDI) was used to evaluate the early (E) and late (A) LV filling velocity and the early (E') and late (A') diastolic mitral annular velocity. In all patients, Holter ECG monitoring (HM ECG) of heart rhythm was performed for 3 days, and ECG monitoring with telemedicine technologies was performed for 7 days, 3 times a day for 3 minutes. The follow-up period was 3 months or until an AF episode.

Results: During the study, paroxysmal AF (pAF) was detected in 41 (24.4%) patients using various methods of heart rhythm monitoring. Complaints of palpitations were noted for 10 (24.4%) patients during pAF, which was recorded using a CardioQVARK® device, HM ECG or a 12-lead ECG. In 5 (12.2%) patients, daily ECG monitoring revealed pAF without associated complaints. HM ECG detected 8, 2, 4 (19.5%, 4.8%, and 9.7%) cases during 24, 48 and 72 hours, respectively; a single-channel CardioQVARK® detected 30 (73.2%) cases when used 3 times a day for 7 days. These results showed that AF frequently develops in CHF without accompanying symptoms. The method for detecting pAF with CardioQVARK® showed good results: it was twice more effective than HM ECG and three times more effective than 12-lead ECG. Also, according to ultrasound data, significant changes in the following parameters were noted in patients with AF: LA EF <36% (OR 1.04, 95% CI: 1.02-1.08), p=0.003; LA GS <9.9% (OR 1.16, 95% CI: 1.02-1.38), p<0.001; TDI E med <5.7 cm/s (OR 0.97, 95% CI: 0.94-1.00), p=0.026. Grade 2 DD did not show statistically significant results (OR 1.1, 95% CI: 0.7-1.5, p=0.54). However, it was detected more frequently in patients with AF, in 34% of cases, compared to 29% of cases in patients without AF, which requires further study on a larger patient sample.

Conclusion: Patients with CHF have a high risk of developing pAF (24.4%). 75% of patients with AF do not feel the development of paroxysm. All CHF patients should undergo EchoCG with assessment of LA EF, TDI E med and LA GS to identify a group at risk for the development of AF. Heart rhythm remote monitoring with CardioQVARK® devices can be considered a reliable method for early detection of pAF and timely initiation of anticoagulant therapy in patients with CHF.