onstrictive pericarditis (CP) is a well-recognized, but rare, complication of open-heart surgery that was first reported in 1972 after coronary artery bypass grafting (CABG). 1 Since then, there have been isolated case reports of CP as a sequela of CABG. The incidence of CP is estimated to be 0.2-0.3%, 2 but once it develops medical treatment is not effective because of the low cardiac output caused by the limitation of diastolic filling of the left ventricle. Although pericardiectomy is recommended, it has a degree of risk and may not necessarily give a good long-term result. We reviewed the clinical characteristics of patients with CP after CABG to ascertain the risk factors for its development.
MethodsFrom January 1989 through March 1999, 463 patients underwent isolated CABG with cardiopulmonary bypass. All patients were subjected to mild hypothermia or normothermia, established by ascending aorta cannulation and single venous cannulation through a median sternotomy. Cardiac arrest was achieved with crystalloid cardioplegic solution infusion, and the heart was cooled with topical ice slush. After weaning from the bypass, the pericardial cavity was irrigated with saline solution alone. Neither antibiotics or povidone-iodine solution was used. The pericardium was left open, and chest tubes were placed in the anterior mediastinum and pericardial cavity prior to chest closure. After surgery, 2-dimensional echocardiography was routinely performed on postoperative days 7-10, and the amount of pericardial effusion was monitored. Patients with dilated saphenous vein grafts or a small coronary artery had oral warfarin therapy, which was started immediately after removal of the chest tubes. Cardiac catheterization and coronary angiography were also performed during postoperative week 2. When the pericardial effusion was moderate or severe, the first choice of treatment was non-steroidal anti-inflammatory agents and an increased dose of diuretics. If these treatments did not reduce the effusion, the second treatment choice was corticosteroids or pericardial drainage. Once CP was clinically suspected during the follow-up period, cardiac catheterization was again performed, in addition to computed tomography (CT) scanning, in order to establish the diagnosis.
Statistical AnalysisThe data are reported as means ± standard deviation. Each group was compared univariately with chi-squared and Fisher's exact tests for categorical variables, and the Student's t test for continuous variables. Multiple logistic regression analysis was performed to identify the risk factors for the development of CP. A p value less than 0.05 were considered to be statistically significant.
ResultsThe mean follow-up period was 54±31 months (maximum, 112 months) and the follow-up rate was 97%. Of the 463 patients who underwent CABG, 11 (2.4%) developed postoperative CP (8 males, 3 females; mean age, 65 years, Jpn Circ J 2001; 65: 480 -482 (Received January 12, 2001; revised manuscript received February 16, 2001; accepted February 26, 2001 Constric...