Incidence and risk factors of conducting system abnormalities after open heart surgery

Abstract

Postoperative implantation of permanent pace maker is a serious complication in patient undergoing open valve surgery (Ben Ameur et al., 2006). Identifying the mechanisms that cause injury to the conduction system, and recognizing risk factors may reduce its incidence, or at least prepare for this eventuality in order to make timely decisions. In the informed consent, a percentage range of prevalence of PPM according to the patient's risk factors and type of surgery should be included. The importance of this information for the patient should not be underestimated. As a routine temporary epicardial pacing wires implanted at the time of surgery (Gordon et al., 1998). This retrospective study compared two post valve surgery groups in order to find out the Incidence and risk factors of conducting system abnormalities following open valve surgery as regards preoperative, intra operative and postoperative variables. One hundred and Sixty one patients were included in the study at Dar Al Fouad Hospital. Their mean age was 49.97 ± 11.23 years, 108 were males (67.1%) and 53 were females (32.9%) All the161 patients included in the current study underwent first time valve surgery with ejection fraction (EF) more than 45%. All records were analyzed for history taking, full cardiac examination, 12 lead surface ECG daily starting by the 1st day till the 14th day postoperative, resting TTE which includes; assessment of LA dimensions, LV dimensions & 2D EF by Simpson method preoperative and postoperative and recording of surgical details for each patient and any complication intra operative or postoperative. The studied population then divided into two groups according to occurrence of postoperative bradycardia. Group I (Bradycardia group): 74 patients who developed postoperative bradycardia which require temporary pace maker insertion. Group II (control group): 87 patients who did not develop bradycardia postoperatively. Patients with history of previous open heart surgery, preoperative presence of any type of AVB, chronic kidney disease and chronic renal failure were excluded from the study. Statistical analysis of the collected clinical data showed no significant difference between two groups regarding demographic data, echocardiographic data. Statistical analysis of the collected data showed no significant difference between two groups regarding preoperative presence of AF, it showed also no significant difference between two groups regarding type of operated valve (aorta, mitral or both) or type of valve lesion (stenosis, regurgitation or double valve lesion) Data analysis showed that intra operative bypass time, cross clamp time in group (I) was statistically significantly higher in comparison to group (II) Upon comparing our two groups statistical significant difference was obtained upon postoperative administration of amiodarone in patients who developed postoperative.