Predictors of rhythm disorders following cardiac surgery
Authors: Danilevych TD , Rasputina LV , Mostovoy YM , Belinskyi AV 
Published: May 2021

Abstract

Funding Acknowledgements
Type of funding sources: None.
Background. Identification of high-risk patients and predictors for cardiac arrhythmias allows the development of preventive measures that will improve the postoperative period and rehabilitation of patients following cardiac surgery.
Purpose. To determine probable predictors of arrhythmias in patients following cardiac surgery in the early postoperative period (up to 7 days).
Methods. 56 patients were examined, including 19 (33.9%) men (p = 0.02). The average age of the patients was 60.86 ± 8.87 years. Cardiac surgery was performed for coronary heart disease in 37 (66.1%) and valvular heart defects in 19 (33.9%) patients (p = 0.02). The average duration of the operations was 371.94 ± 102.04 minutes. In 25 (44.6%) cases, the operations were performed in conditions of bypass, the average duration of which did not differ from operations without bypass (389.44 vs. 355.47, p = 0.34). Assessment of arrhythmias was performed during the first 7 days after cardiac surgery.
Results. 27 (48.2%) patients have developed arrhythmias within first 7 days, among them in 12 (63.2%) women and 15 (40.5%) men (p = 0.24). Predictors of arrhythmias in early postoperative period are: operation with bypass r = 0,332 [1,06-3,03], p = 0,01; the size of left atrium (LA)&gt; 40 mm r =0,296 [1,01-3,31], p = 0,03; presence of coronary artery (CA) stenosis r = 0,139 [1,11-2,69], p = 0,04; atrial fibrillation (AF) in the history r = 0,607 [1,99-5,58], p = 0,001.
AF dominates in the structure of arrhythmias – in 17 (30.4%) patients, among them – in 11 (64.7%) was paroxysmal, 6 (35.3%) patients - persistent form. The mean score of CHA2DS2VASc scale - 2.56 ± 0.89. The predictors of AF are: operation with bypass r = 0.451 [1.63-9.76], p= 0.0001; the size of the LA&gt; 40 mm r = 0.303 [1.04-7.58], p = 0.02; left ventricle (LV) ejection fraction (EF) &lt;40% r = -0.207 [1.23-1.82], p = 0.05; mitral regurgitation r = 0.314 [1.05-10.04], p = 0.02.
Also registered ventricular ventricular prematute beats (VPB) – in 12 (21.4%) patients, among them VPB 1st Laun class - in 8 (66.7%), 2nd Laun class – in 2 (16.7%), 3rd Laun class – in 1 (8.3%), 4A Laun class – in 1 (8.3%) patient, respectively. Predictors of VPB are: chronic heart failure (CHF) 4 functional class (FC) r = 0.258 [2.94-8.48,], p = 0.05; CA stenosis r = 0,282 [1,04-40,54], p = 0,04; LV EF &lt;50% r = -0.344 [1,3-9,42], p = 0,009, stroke in the anamnesis r = 0,262 [1,33-9,37], p = 0,05.

Conclusions
The prevalence of arrhythmias in the early postoperative period (up to 7 days) following cardiac surgery is 48.2%. The predictors of arrhythmias are: operation with bypass, the size of LA&gt; 40 mm, presence of CA stenosis and any form of AF in the history.
AF dominates in the structure of heart arrhythmias (30.4%). The predictors of AF are: operation with bypass, the size of the LA&gt; 40 mm, LV EF &lt;40%, mitral regurgitation according to echocardiography; predictors of VPB are: CHF 4 FC, CA stenosis, LV EF &lt;50%, stroke in the history.