Poor long-term outcomes of intravenous drug users with infectious endocarditis

OBJECTIVES: The optimal management of active endocarditis in intravenous (IV) drug users is still lacking. METHODS: From the years 1997 to 2017, 536 patients with active infectious endocarditis were surgically treated, including 83 (15%) with IV drug use (IVDU) and 453 (85%) without IV drug use (non-IVDU). Initial data were obtained from the Society of Thoracic Surgeons database and supplemented with chart review and national death index data. RESULTS: The IVDU group was significantly younger (43 vs 56 years old) than the non-IVDU group and had greater rates of psychiatric disorders, drug use, and tricuspid valve endocarditis (28% vs 8.6%). Hypertension, dyslipidemia, and diabetes mellitus were significantly more common in the non-IVDU group. Perioperative complications and operative mortality (7.2% vs 7.9%) were similar. IVDU was not a significant risk factor for operative mortality. Kaplan–Meier survival was significantly lower in the IVDU group (5-year survival, 46% vs 67%). Significant risk factors for long-time mortality included IV drug use (hazard ratio [HR], 1.92), age ≥65 years (HR, 1.78), congestive heart failure (HR, 1.87), and enterococcus endocarditis (HR, 1.54). The 5-year rate of reoperation was similar between IVDU and non-IVDU groups (2.4% vs 2.7%). CONCLUSIONS: IVDU is a significant risk factor for long-term mortality. A multidisciplinary approach was preferred for IVDU patients to treat both endocarditis and substance use disorder and improve long-term survival.