A normal or (on the other end) a very high level of NT-proBNP should make us look for a cause other than aortic stenosis. If aortic stenosis is not the culprit of the clinical case, a transcatheter aortic valve replacement (TAVR) will hardly benefit these patients.
These data come from a recently published paper in J Am Heart Assoc that may turn NT-proBNP into a valuable tool for TAVR decision-making.
Values under 800 ng/L (deemed normal) or extremely high above 10,000 ng/L identify patients who will not get symptomatic relief after the procedure.
Nobody doubts how beneficial TAVR is for patients with symptomatic aortic stenosis; however, we should bear in mind that said relief is not for all. Up to 30% of patients still experience similar symptoms or die within a year.
This is too large a percentage not to try to fine-tune patient selection.
This study included 144 patients (mean age, 83 years) who underwent TAVR and a baseline NT-proBNP analysis.
NT-proBNP makes a “U” curve, where levels under 800 or above 10,000 ng/L predict futility with an 88% sensitivity and an 83% specificity.
In more than half of the cases where the NT-proBNP level was below 800 and the symptoms were not relieved by TAVR, chronic lung disease could explain the dyspnea.
On the other end, a NT-proBNP level above 10,000 may indicate an irrevocably diseased left ventricle.
This work that arises from a single high-volume site is a hypothesis generator. We must keep searching for indicators for better patient selection.
Original Title: Baseline NT-proBNP accurately predicts symptom response to transcatheter aortic valve implantation.
Reference: Allen CJ et al. J Am Heart Assoc. 2020;9:e017574.