Mediastinitis after cardiac valve operations. Impact upon survival

Abstract

Mediastinitis after cardiac valve replacement is a dreaded complication with consequent mortality estimated as high as 70%. We have reviewed 2,491 patients with cardiac valve operations to assess the impact of mediastinitis upon mortality in our institution in the past 10 years. Mediastinitis developed after valve replacement in 36 patients (1.4%). All patients required operative intervention for mediastinal infection with positive bacterial cultures. Twelve of these patients had other perioperative problems associated with a high mortality independent of mediastinitis: bacterial endocarditis not cured by valve replacement (three), recent preoperative myocardial infarction (four), triple valve disease with biventricular failure (one), and severe perioperative cerebral damage (four). Ten of these high-risk patients died (83.3%). The impact of mediastinitis upon survival is best evaluated in the remaining 24 patients without high-risk perioperative problems. Eight of these patients were managed before 1980 with débridement and irrigation as the primary treatment, with two hospital deaths (25%). Pectoral or rectus muscle flaps were frequently used after 1980 (flaps in 11 of 16 patients), leading to a significantly shorter time between diagnosis of infection and hospital discharge free of infection (62 versus 385 days, p less than 0.05). Only one of these 16 patients died. Valve re-replacement for endocarditis was performed in three of these 24 patients although 13 of 24 had positive blood cultures. Mediastinitis after valve operations in the absence of other high-risk perioperative problems can be successfully managed. Early débridement and muscle flap closure has led to a 94% survival rate in 16 patients during the past 4 years.