(P174) ADDITIVE VALUE OF NT-PROBNP RATIO IN THE MANAGEMENT OF MIXED AORTIC VALVE DISEASE PATIENTS

Background: Management of mixed aortic valve disease (MAVD: concomitant aortic stenosis [AS] and regurgitation [AR]) remains challenging. Delay in therapeutic intervention and poor postoperative outcomes after aortic valve replacement (AVR) despite normal preoperative LV function has been reported in these patients. We thus aimed to assess the additive prognostic value of N-terminal pro-brain natriuretic peptide (NT-proBNP) ratio in risk stratification of these patients.

METHODS AND RESULTS: Clinical and Doppler-echocardiographic data of 582 consecutive MAVD patients (mean age 73±11 years, 63% men) with at least concomitant mild AS and mild AR in whom a measurement of NT-proBNP during the same episode of care was available were analyzed. NT-proBNP absolute value and ratio (i.e., measured plasma level divided to maximal normal values for age and sex derived from Mayo Clinic laboratory) were tested as continuous, categorical or dichotomic variables. Baseline median NT-proBNP absolute value and ratio were respectively 525 ng/L (interquartile range [IQR]: 202 – 1762) and 3.5 (IQR: 1.2 to 10.0). In patients who underwent early AVR within 3 months (n=429, 74%), NT-proBNP-ratio ≥3 was associated with higher 30-days mortality (9 [4%] vs. 1 [0.5%], p=0.02). During a median follow-up of 5.6 years (IQR: 2.8-6.1), 105 patients died. Both NT-proBNP absolute value and ratio as continuous, categorical or dichotomic (≥ 3 vs. < 3) variables were significantly associated with long-term all-cause mortality (Figure). In comprehensive multivariable analyses adjusted for clinical and echocardiographic parameters as well as AVR as time-dependent variable, NT-proBNP-ratio was independently associated with increased risk of mortality (continuous variable: HR [95% CI]: 1.24 [1.05-1.46], p = 0.01; NT-proBNP-ratio ≥ 3: 2.52 [1.42-4.47], p = 0.002). NT-proBNP-ratio as a continuous and a dichotomous variable also showed incremental prognostic value to predict increased risk of mortality at 1, 2 and 5 years over EuroSCORE II and echocardiographic parameters (all net reclassification index > 0.45, all p ≤ 0.005; Table).

Conclusion: In this series of MAVD patients, NT-proBNP-ratio was a powerful predictor of early and long-term mortality and provided incremental prognostic value over parameters currently used for management. These findings also suggest that AVR may be reasonable before reaching an NT-proBNP-ratio ≥ 3.