Modified chest wall reconstruction after sternum necrosis in cardiac surgery patients

Objective: Complete or partial sternal bone necrosis in poststernotomy patients leads to prolonged hospitalization, distress, reduced quality of life and if untreated to a high mortality. Our proposed treatment of this complication comprises a chest wall reconstruction with metal plates and wires combined with musculocutaneous flap wound closure.

Methods: In the last 3 years, more than 3000 median sternotomies were performed in our hospital. Only 8 (0.20%) patients (2 male/6 female) developed a sternum necrosis following internal thoracic artery (IMA) harvesting. In all cases the operative preparations were similar: After vacuum assisted closure (VAC) therapy and complete necrotic tissue debridement, the anterior chest wall was reconstructed with titanium osteosynthesis plates. Two Kirschner steel wires were used in para-median position to mobilize bilateral pectoral musculocutaneous flaps and to complete a tension-free edge-to-edge wound closure.

Results: The mean patient age was 74 (± 6.3) years. In all patients, a left IMA was harvested, in 2 patient both IMAs were used; 50% of patients presented with type II diabetes, 50% with COPD > GOLD II. The mean BMI was 27.6 (± 3.5). 83.3% suffered from renal insufficiency, 66.6% from peripheral arterial occlusive disease. The mean operation time was 189.3 (± 50.4) min. Overall ICU-stay was prolonged (10 ± 9.9 days). In microbiological cultures, 83.3% staphylococci (40% MRSA, 40% MRSE, 3.3% S. aureus) and 16.7% gram-negative species were isolated. The chest wall reconstruction was performed after 25.7 (± 12.9) days of VAC-therapy. Both Kirschner wires were removed on the 6th postoperative day. The mean length of hospital stay after CABG was 39.2 (± 14.2) days due to multi-resistant staphylococci mediastinitis. Patients were discharged 10.3 (± 3.6) days after secondary wound closure. There was no recurrent sternal wound infection. No functional and aesthetical complaints were registered during the follow up period (mean 22 ± 14.1 weeks). One patient died during the follow up time due to sepsis after hip prosthesis infection.

Conclusion: A combined surgical strategy using osteosynthesis plates to stabilize the thorax and bilateral pectoral musculocutaneous flaps for secondary wound closure can be considered as an effective therapeutic option for reconstruction following sternal necrosis and mediastinitis, since functionality and aesthetic appeal of the chest are preserved.