Introduction

Cavalier King Charles Spaniels (CKCS) are predisposed to developing myxomatous mitral valve disease (MMVD). Dogs with stage B2 MMVD benefit from medication.

Objectives

To develop (1) breed-specific cut-offs for individual screening tests and (2) predictive models utilizing physical examination (PE), ECG, radiograph, and blood-based biomarker variables in combination for identification of echocardiographic stage B2 MMVD in preclinical CKCS.

Animals

Adult, preclinical CKCS not receiving cardiac medications (N = 226).

Materials and methods

Prospective, cross-sectional study. Enrolled CKCS underwent PE, ECG, radiography, Doppler blood pressure measurement, echocardiography, and biomarker testing. Dogs were grouped by MMVD stage using echocardiography only. The discriminatory ability of individual tests to identify stage B2 was assessed, and prediction models were developed using variables derived from four ‘tests’ (PE, ECG, radiography, and biomarkers).

Results

N-terminal pro-B-type natriuretic peptide (NT-proBNP) and radiographic vertebral heart size (VHS) had the best discriminatory ability of individual diagnostic tests to differentiate stage A/B1 CKCS from stage B2, with an area under the curve (AUC) of 0.855 and 0.843, respectively. An NT-proBNP ≥1138 pmol/L or a VHS ≥11.5 had high specificity for predicting stage B2 (90.1% and 90.6%, respectively). Prediction models incorporating variables from multiple tests had better discriminatory ability than single tests. The four-test prediction model had an AUC of 0.971. Three and two-test models had AUCs ranging between 0.925–0.959 and 0.895–0.949, respectively.

Conclusions

Both NT-proBNP and VHS have good utility for predicting echocardiographic stage B2 MMVD in CKCS as individual tests. Prediction models incorporating multiple test variables have superior discriminatory ability.

中文翻译：

---

使用体检、心电图、放射线照相和生物标志物预测临床前骑士查理王小猎犬的超声心动图 B2 期粘液瘤性二尖瓣疾病

介绍

查理王小猎犬 (CKCS) 容易患粘液瘤性二尖瓣病 (MMVD)。患有 B2 期 MMVD 的狗可以从药物治疗中受益。

目标

开发 (1) 用于个体筛选测试的特定品种截止值和 (2) 利用体检 (PE)、心电图、放射线照片和基于血液的生物标志物变量相结合的预测模型，以识别临床前 CKCS 中的超声心动图 B2 期 MMVD 。

动物

未接受心脏药物治疗的成人临床前 CKCS (N = 226)。

材料和方法

前瞻性、横断面研究。登记的 CKCS 接受了 PE、心电图、放射线照相、多普勒血压测量、超声心动图和生物标志物测试。仅使用超声心动图对狗进行 MMVD 分期分组。评估了各个测试识别 B2 阶段的辨别能力，并使用从四个“测试”（PE、心电图、放射线照相和生物标志物）派生的变量开发了预测模型。

结果

N 端 B 型利钠肽原 (NT-proBNP) 和放射学椎心大小 (VHS) 在个体诊断测试中具有最佳区分能力，可区分 A/B1 期 CKCS 与 B2 期，曲线下面积（ AUC）分别为 0.855 和 0.843。NT-proBNP ≥1138 pmol/L 或 VHS ≥11.5 对预测 B2 期具有很高的特异性（分别为 90.1% 和 90.6%）。包含多个测试变量的预测模型比单个测试具有更好的区分能力。四次检验预测模型的 AUC 为 0.971。三个和两个测试模型的 AUC 范围分别为 0.925-0.959 和 0.895-0.949。

结论

作为单独测试，NT-proBNP 和 VHS 对于预测 CKCS 中超声心动图 B2 期 MMVD 都有很好的实用性。包含多个测试变量的预测模型具有优越的判别能力。