Background: Left ventricular assist devices (LVAD) improve survival for patients with cardiac failure, but LVAD specific infections (VSI) remain a challenge with poorly understood predictive risk factors. Furthermore, the indications and utility of escalating medical treatment to surgical debridement and potential flap reconstruction are not well-characterized.
Study design: A retrospective review of consecutive patients undergoing primary LVAD implantation at a tertiary academic center was performed. The primary outcomes measures were 90-day and overall mortality after VSI. Cox proportional hazards regression was used to generate a risk-prediction score for mortality.
Results: Of the 760 patients undergoing primary LVAD implantation, 255 (34%) developed VSI; of these 91 (36%) were managed medically, 134 (52%) with surgical debridement, and 30 (12%) with surgical debridement and flap reconstruction. One-year survival after infection was 85% with median survival of 2.40 years. Factors independently associated with increased mortality were diabetes (hazard ratio (HR) 1.44, p=0.04), methicillin-resistant Staphylococcus aureus infection (HR 1.64, p=0.03), deep space (pump pocket/outflow cannula) involvement (HR 2.26, p<0.001) and extra-corporeal membrane oxygenation after LVAD (HR 2.52, p<0.01. Factors independently associated with decreased mortality were flap reconstruction (HR 0.49, p=0.02) and methicillin-sensitive Staphylococcus aureus infection (HR 0.63, p=0.03). A clinical risk prediction score was developed using these factors and showed significant differences in median survival, which was 5.67 years for low-risk (score 0-1), 3.62 years for intermediate-risk (score 2), and 1.48 years for high-risk (score >3) (p<0.001) patients.
Conclusions: We developed a clinical risk prediction score to stratify VSI patients. In selected cases, escalating surgical treatment was associated with increased survival. Future work is needed to determine if early surgical debridement and flap reconstruction can alter outcomes in select cases of VSI.
