Introduction
The most common arrhythmia following cardiac surgery is atrial fibrillation (AF), and its incidence is 20-40%. Despite advances in surgical techniques and myocardial protection methods, and innovations in anesthesia, postoperative atrial fibrillation (PoAF) is still common after coronary artery bypass grafting (CABG) especially due to the advanced age of the patient population (1). It is known that predicting PoAF development prior to operation provides a significant reduction in morbidity, mortality and hospitalization times (2,3). The pathophysiology of PoAF is multifactorial. Although it is considered that it develops due to advanced age, electrolyte imbalance, hypertension, atrial fibrosis, atrial adhesions, intraoperative ischemia, increase in postoperative sympathetic activity, and volume loading, its pathophysiology has not yet been explained fully. For this reason, there is no proven prophylactic treatment strategy (4,5).
Atrial electromechanical delay (AEMD) defines the time interval between the initial point of P wave in 12-led electrocardiography (ECG) and the formation of the late diastolic wave in Tissue Doppler Imaging (TDI). This delay between the electrical stimulation and mechanical contraction, in other words, atrial electrophysiological changes, cause AF development by affecting the anatomy of atrium (6). Our aim in this study was to investigate the predictive value of AEMD duration, which can be easily detected by pre-operatively routinely performed ECG and transthoracic echocardiography (TTE) (using TDI), in the development of PoAF in isolated CABG patients.
Material and Methods
Patients and study design
The data of 93 patients who underwent cardiopulmonary bypass (CPB) with isolated CABG between October 2016 and May 2017 were examined in this prospective study. Our study was approved by the Ethics Board of Clinical Research of University of Health Sciences Bursa Yuksek Ihtisas Training and Research Hospital; and the written consents of the patients who were included in the study were obtained.
The patients between the ages of 18 and 80, scheduled for isolated CABG and who had sinus rhythm were included in the study. Those with valvular heart disease requiring surgical intervention, those who had previously undergone open heart surgery, those with severe low left ventricular ejection fraction (EF) (EF <35%), those with severe cardiac segmental wall activity abnormalities, those with severely dilated left atrium (LA > 50 mm), those with a history of ablation due to AF, those with preoperative\sout, bradyarrhythmia or tachyarrhythmia were not included in the study.
In total, 120 patients were evaluated in this study, and 93 patients met the study criteria. Seven patients with poor image quality, 4 patients with arrhythmia before the procedure, 5 patients with severe valve dysfunction, 7 patients who were given antiarrhythmic during or after the procedure, were excluded from the study.
The demographic characteristics, comorbidities, preoperative and postoperative laboratory parameters, preoperative TTE parameters, preoperative AEMD values, perioperative and postoperative variables of the patients were recorded.