The impact of estimated glomerular filtration rate (eGFR) on adverse events in patients with mechanical heart valves (MHVs) is unknown. We analyzed the independent association of eGFR and thromboembolism (TE), major bleeding, and mortality in patients with MHV in an observational cohort study.

All patients (n = 520) with MHV replacement on anticoagulation treatment were followed up prospectively regarding TE, major bleeding, and death at 2 anticoagulation centers during 2008 to 2011. The mean age was 69 years, 72% with aortic valve replacement, and time in therapeutic range 2.0 to 4.0 was 91%. The incidence of the combined end point of major bleeding, TE, and death increased sharply with each decreasing eGFR stratum: 5.5, 8.4, 16, and 32 per 100 patient-years for eGFR >60, 45 to 60, 30 to 45, and <30 mL/min per 1.73 m², respectively. After multivariate adjustment for comorbidities, every unit decrease in eGFR increased the risk of major bleeding by 2%, death by 3%, and the combined end point by 1%. There was no association between eGFR and TE. There was an increased proportion of international normalized ratio >3.0 and >4.0 and decreasing time in therapeutic range for each decreasing eGFR stratum (P < .001 for trend). The hazard ratios of the combined end point for eGFR <30, 30 to 45, and 45 to 60 mL/min per 1.73 m² were 3.2 (95% CI 1.8-5.6), 1.5 (95% CI 0.9-2.5), and 0.9 (95% CI 0.6-1.5), respectively, compared to eGFR >60 mL/min per 1.73 m².

In patients with MHV on anticoagulation, eGFR is an independent predictor of major bleeding and death and not TE.