STratification risk analysis in OPerative management (STOP score) for drug-induced endocarditis

Background: The opioid epidemic has seen a drastic increase in the incidence of drug-associated infective endocarditis (IE). No clinical tool exists to predict operative morbidity and mortality in patients undergoing surgery. Methods: A multi-institutional database was reviewed between 2011 and 2018. Multivariate logistic regression was fitted in an automated stepwise fashion. The STratification risk analysis in OPerative management of drug-associated IE (STOP) score was constructed. Morbidity was defined as reintubation, prolonged ventilation, pneumonia, renal failure, dialysis, stroke, reoperation for bleeding, and a permanent pacemaker. Cross-validation provided an unbiased estimate of out-of-sample performance. Results: A total of 1181 patients underwent surgery for drug-associated IE (median age, 39; interquartile range [IQR], 30–54, 386 women [32.7%], 341 reoperations for prosthetic valve endocarditis [28.9%], 316 patients with multivalve disease [26.8%]). Operative morbidity and mortality were 41.1% and 5.9%, respectively. Predictors of morbidity were dialysis (95% confidence interval [CI], 1.16–2.82), emergent intervention (1.83-4.73), multivalve procedure (1.01–1.98), causative organisms other than Streptococcus (1.09–2.02), and type of valve procedure performed [aortic valve procedure (1.07–2.15), mitral valve replacement (1.03–2.05), tricuspid valve replacement (1.21–2.60)]. Predictors of mortality were dialysis (1.29–5.74), active endocarditis (1.32–83), lung disease (1.25–5.43), emergent intervention (1.69–6.60), prosthetic valve endocarditis (1.24–3.69), aortic valve procedure (1.49–5.92) and multivalve disease (1.00–2.95). Variables maximizing explanatory power were translated into a scoring system. Each point increased odds of morbidity and mortality by 22.0% and 22.4% with an accuracy of 94.0% and 94.1%, respectively. CONCLUSION: Drug-related IE is associated with significant morbidity and mortality. An easily-applied risk stratification score may aid in clinical decision-making.