Delayed Sternal Closure Does Not Increase Late Infection Risk in Patients Undergoing Left Ventricular Assist Device Implantation

BACKGROUND:

Delayed sternal closure (DSC) is employed after conventional cardiac surgery without a significantly increased risk of late mediastinitis or sternal wound infection. There are no data specifically examining its late effects on patients undergoing implantation with a ventricular assist device (VAD).

METHODS:

Between October 1996 and October 2010, 364 patients underwent primary VAD implant and DSC was utilized in 184 (51%) patients for coagulopathy (n = 155; 84%), hemodynamic instability (n = 103; 56%), isolated right ventricular dysfunction (n = 15; 8%) or unspecified reasons (n = 17; 9%).

RESULTS:

Median duration of DSC was 1 day (range 1 to 7 days). Patients with DSC were older (54.5 vs. 50.3 years, p = 0.002), had a higher incidence of previous sternotomy (42% vs. 28%, p = 0.005), pre-operative intra-aortic balloon pump (50% vs. 30%, p < 0.001), pre-operative temporary extracorporeal mechanical circulatory support (23% vs 10%, p < 0.001), lower platelet counts (171,000 vs. 209,000, p < 0.001) and lower hematocrit levels (32% vs. 36%, p < 0.001). Operative (11% vs. 9%, p = 0.65) or late (2 years; 66 ± 7% vs 66 ± 7%, p = 0.720) mortality; composite incidence of mediastinitis, percutaneous drive-line infection, pocket infection and VAD-related endocarditis (15% vs. 16%, p = 0.79); re-exploration for bleeding (18% vs. 18%, p = 0.99); urgent transplantation for infection (4% vs. 3%, p = 0.99); or need for device exchange (9% vs. 10%, p = 0.16) was not increased after DSC when compared with immediate sternal closure. DSC increased ICU stay (10 vs. 5 days, p = 0.001).

CONCLUSIONS:

DSC was performed most commonly for coagulopathy and/or hemodynamic instability, and patients were older with a greater severity of illness as shown by the higher incidence of right-sided circulatory failure and history of prior sternotomy. Although DSC was associated with longer ICU stay, DSC was not associated with a significantly increased risk of death or infection.