Septic rupture of the ascending aorta after aortocoronary bypass surgery

Sternal dehiscence is a frequent complication after aortocoronary bypass surgery with an incidence estimated at 1% to 6% in a normal population [1]. When complicated by sternum osteomyelitis and DSWI, prolonged hospitalization and increased cost of care, morbidity and mortality as high as 20% is reported [2]. Broken wire fixations and displaced bone fragments with non-physiological sternal movement seem to be essential in its pathogenesis [3]. Obesity, diabetes mellitus, chronic obstructive pulmonary disease and previous sternotomy make up the major risk factors [4]. Despite antibiotic therapy and aggressive surgical interventions, the prognosis is serious [5]. In this case report, we describe a patient developing non-fatal septic rupture of the ascending aorta with mediastinal pseudoaneurysm triggered by sternum osteomyelitis and extensive DSWI after aortocoronary bypass surgery.A 65-year-old male white was referred to our department for routine follow-up CT for sternal dehiscence, DSWI and pleural empyema developing after aortocoronary bypass operation 9 months before. His history included congenital portal vein stricture with recurrent ascites, acute myocardial infarction 4 months ago, systemic hypertension, hypercholesteremia, renal insufficiency, penicillin allergy and methicillin-resistant staphylococcus aureus in the blood culture. Medication consisted of spironolactone, metoprolol succinate, furosemide, ramipril, acetylsalicylate, zinc aspartate and zolpidem tartrate. Physical examination was carried out in the Department of Cardiac Surgery right before the CT and revealed pressure-like pectoral pain and non-physiological sternal movement. Laboratory showed elevated c-reactive protein (58 mg/l), ferritin (1450 μg/l) and gamma-glutamyl transferase (77 U/l), whereas choline esterase (3110 U/l) and hemoglobin (12.5 g/dl) were reduced. Electrocardiogram and tropoine T were unremarkable. CT detected massive sternal bone defects, inhomogenous bone matrix and irreg