Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Iowa State University, 1809 S. Riverside Drive, Ames, IA 50011, USA.
Department of Veterinary Pathology, College of Veterinary Medicine, Iowa State University, 1809 S. Riverside Drive, Ames, IA 50011, USA.
J Vet Cardiol. 2020 Aug;30:44-56. doi: 10.1016/j.jvc.2020.05.003. Epub 2020 May 29.
This study describes presentation, cardiovascular abnormalities, etiology, and outcome of canine myocarditis in geographic areas not endemic for Trypanosoma or Leishmania.
Sixty-four (presumed antemortem diagnosis) and 137 (postmortem diagnosis only) client-owned dogs at two tertiary care facilities were included.
Medical records of dogs with clinical or histopathological diagnosis of myocarditis were reviewed retrospectively.
Common examination findings in dogs with a presumed antemortem diagnosis included fever (21%) and heart murmur (19%). Median cardiac troponin I was 12.2 ng/mL (range: 0.2-808.0 ng/mL), and troponin exceeded 1.0 ng/mL in 26 of 29 (90%) dogs. Ventricular ectopy was the most common arrhythmia (54%), whereas decreased left ventricular systolic function was the most common echocardiographic abnormality (56%). An infectious etiology was diagnosed in 35 of 64 (55%) dogs. Confirmed infectious etiologies included bacterial sepsis (n = 9) or extension of endocarditis (3), toxoplasmosis or neosporosis (3), parvovirus (2), and one case each of bartonellosis, trypanosomiasis, leptospirosis, and dirofilariasis. Median survival time was 4 days (range: 0-828 days) for all dogs vs. 82 days for dogs who survived at least 2 weeks after diagnosis. Presence of pericardial effusion or azotemia was a significant predictor of non-survival. The most common inflammatory infiltrate on histopathology was neutrophilic (47%), and 20 of 137 (14.5%) dogs had concurrent bacterial endocarditis on postmortem.
Bacterial infection was the most common confirmed etiology of myocarditis in this study. Prognosis for canine myocarditis is guarded and similar to that reported for infective endocarditis. Criteria for the antemortem diagnosis of canine myocarditis are suggested.
本研究描述了在无锥虫或利什曼原虫流行地区的犬心肌炎的临床表现、心血管异常、病因和转归。
两所三级保健中心的 64 只（假定生前诊断）和 137 只（仅死后诊断）患犬被纳入研究。
回顾性分析了具有临床或组织病理学诊断为心肌炎的犬的病历。
生前诊断为心肌炎的犬常见的检查结果包括发热（21%）和心杂音（19%）。中位心肌肌钙蛋白 I 为 12.2ng/mL（范围：0.2-808.0ng/mL），29 只犬中有 26 只（90%）的肌钙蛋白超过 1.0ng/mL。室性心律失常最常见（54%），而左心室收缩功能障碍最常见（56%）。35 只（55%）犬诊断为感染性病因。确定的感染性病因包括细菌性败血症（9 例）或心内膜炎扩展（3 例）、弓形虫病或新孢子虫病（3 例）、细小病毒（2 例）和巴贝斯虫病、锥虫病、钩端螺旋体病和心丝虫病各 1 例。所有犬的中位生存时间为 4 天（范围：0-828 天），至少存活 2 周的犬的中位生存时间为 82 天。存在心包积液或氮质血症是不能存活的显著预测因素。组织病理学上最常见的炎症浸润是中性粒细胞（47%），137 只犬中有 20 只（14.5%）死后并发细菌性心内膜炎。
在本研究中，细菌感染是犬心肌炎最常见的确诊病因。犬心肌炎的预后较差，与感染性心内膜炎的预后相似。提出了犬心肌炎的生前诊断标准。
