Simple bedside clinical evaluation versus established scores in the estimation of operative risk in valve replacement for severe aortic stenosis

SummaryBackgroundThe operative risk of cardiac surgery is ascertained preoperatively on the basis of scores validated in multinational studies. However, the value they add to a simple bedside clinical evaluation (CE) remains controversial.AimsTo compare operative mortality (defined as death from all causes before the 31st postoperative day) predicted by CE with that predicted by additive and logistic EuroSCOREs, EuroSCORE II and Society of Thoracic Surgeons (STS), Ambler and age-creatinine-ejection fraction (ACEF) scores in patients undergoing aortic valve replacement (AVR) for severe aortic stenosis.MethodsOverall, 314 consecutive patients were included who underwent AVR between October 2009 and November 2011 (22% with coronary artery bypass graft); mean age 73.4±9.7years (29% aged>80years). Based on CE, patients were divided into four predefined groups of increasing estimated mortality risk: I≤3.9%; II 4–6.9%; III 7–9.9%; IV≥10%. The positive and negative predictive values of the six scores and CE were compared.ResultsThe observed overall operative mortality was 5.7%. The distribution of the four predicted mortality groups by each score was highly variable. The positive predictive value, calculated for the 64 patients classified at highest risk by CE (groups III or IV) or each score, was 17.2% for EuroSCORE II, 14.1% for CE and STS scores, 10.9% for additive and logistic EuroSCOREs, 10.6% for ACEF and 10.2% for Ambler. The positive predictive value of each score in the low-risk groups (I and II) ranged from 2.8% to 4.4%.ConclusionA simple bedside CE appears as reliable as the various established scores for predicting operative risk in patients undergoing surgical aortic valve replacement. The development and validation of more comprehensive risk stratification tools, including risk factors thus far neglected, seems warranted