NT-proBNP measurement fails to reliably identify subclinical hypertrophic cardiomyopathy in Maine Coon cats

The purpose of this study was to evaluate the value of measuring plasma NT-proBNP concentration as a screening tool in cats with varying severity of subclinical hypertrophic cardiomyopathy (HCM). Plasma NT-proBNP concentration was measured in 35 cats that had previously been classified as normal, equivocal, moderate HCM or severe HCM via echocardiography. No cat had ever been in congestive heart failure. Cats with severe HCM had a significantly higher NT-proBNP concentration compared to the other groups (P < 0.0003), however, the sensitivity of NT-proBNP for diagnosing cats with severe disease was only 44% (cutoff ≤ 100 pmol/l) to 55% (cutoff ≤ 40 pmol/l). There was no significant difference in NT-proBNP concentration between normal, equivocal and moderate categories (sensitivity for detecting moderate HCM was 0%). Based on the results of this study, NT-proBNP concentration is not considered adequate as a screening test for detecting mild to moderate HCM in Maine Coon cats and it appears that it may miss many cats with severe HCM.