• Open Access

Prospective Evaluation of NT-proBNP Assay to Detect Occult Dilated Cardiomyopathy and Predict Survival in Doberman Pinschers

Authors


  • Preliminary results were presented at the 2009 ACVIM Forum and Canadian Veterinary Medical Association Convention, Montreal, Quebec, Canada.

Corresponding author: M.A. Oyama, Department of Clinical Studies-Philadelphia School of Veterinary Medicine University of Pennsylvania, Philadelphia, PA 19104; e-mail: maoyama@vet.upenn.edu

Abstract

Background

Occult (asymptomatic) dilated cardiomyopathy (ODCM) is highly prevalent in Doberman Pinschers.

Hypothesis/Objectives

Assess ability of NT-proBNP assay to detect ODCM and predict death.

Animals

155 asymptomatic Dobermans presenting for ODCM screening.

Methods

Echocardiography, 24-hour Holter, and NT-proBNP assay were performed prospectively. Diagnosis was based on increased left ventricular end-systolic dimension, >50 ventricular premature complexes (VPCs), or both on Holter. Utility was evaluated using receiver-operating characteristic curves. Effect of age, weight, sex, disease status, VPCs, and NT-proBNP on survival was analyzed using Kaplan-Meier and Cox-proportional hazard analysis.

Results

Seventy-three (47.1%) Dobermans were diagnosed with ODCM, including 31, 17, and 25 that met Holter, echocardiographic, or both criteria, respectively. Sensitivity of NT-proBNP > 457 pmol/L to detect these groups was 45.2, 76.5, and 96.0%, respectively. Combination of NT-proBNP and Holter to detect ODCM yielded sensitivity of 94.5%, specificity of 87.8%, and accuracy of 91.0%. Follow-up data were available for 78 Dobermans. The median survival time of Dobermans with > 50 VPCs (469 days), NT-proBNP > 900 pmol/L (284 days), or ODCM (474 days) was significantly (< .0001) shorter than those with < 50 VPCs (1743 days), NT-proBNP < 900 pmol/L (1743 days), or without disease (1743 days). NT-proBNP concentration and disease status were independently predictive of all-cause mortality.

Conclusions and Clinical Importance

The combination of NT-proBNP assay and Holter detected ODCM with high accuracy. NT-proBNP and disease status were independently associated with survival. NT-proBNP assay identified Dobermans with high probability of increased LVIDs consistent with ODCM, and can facilitate pursuit of confirmatory diagnostic testing, such as echocardiography, in suspected Dobermans.

Ancillary