Department of Small Animal Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas, USA.
J Vet Intern Med. 2021 Jan;35(1):88-97. doi: 10.1111/jvim.15985. Epub 2020 Dec 6.
Heartworms, a cause of pulmonary hypertension (PH) in dogs, can migrate from the pulmonary arteries into the heart resulting in life-threatening caval syndrome (CS).
To describe clinical and echocardiographic characteristics in dogs with intracardiac heartworms including estimated heartworm burden and frequency of PH and pigmenturia.
Seventy-two client-owned dogs with heartworms.
Retrospective study. Data collected from an electronic medical records search for dogs with intracardiac heartworms included clinicopathologic, echocardiographic, and procedural findings. Dogs with heartworms isolated to the pulmonary arteries were excluded.
Estimated intracardiac heartworm burden was low in 14 of 72 (19%) and high in 58 of 72 (81%) dogs. The majority were small breed (54/72; 75%; 29/72; 40% Chihuahuas) and had a high likelihood of PH (67/72; 93%). Pigmenturia was the second most common clinical finding (31/72; 43%) after lethargy (32/72; 44%). Anemia (37/55; 36%), pigmenturia (30/58; 52%), and bilirubinuria (28/36; 78%) were significantly more common in dogs with a high worm burden (P < .05). Based on the presence of anemia, pigmenturia, and clinical signs, 18 of 72 dogs (25%) were considered to have CS.
Although the majority of dogs with intracardiac heartworms had a high worm burden and high likelihood of PH, only 25% had clinical evidence of CS. Echocardiography is a useful tool to identify intracardiac heartworms, detect likelihood of PH, and could be useful for staging heartworm positive small breed dogs for intracardiac heartworm migration.
心丝虫可引起犬肺动脉高压（PH），并从肺动脉迁移到心脏，导致危及生命的腔静脉综合征（CS）。
描述患有心内型心丝虫的犬的临床和超声心动图特征，包括估计的心丝虫负荷以及 PH 和色素尿的发生频率。
72 只患有心丝虫的患犬。
回顾性研究。从电子病历搜索中收集患有心内型心丝虫的犬的临床病理、超声心动图和程序检查数据。排除仅肺动脉有心丝虫的犬。
72 只犬中，14 只（19%）心内型心丝虫负荷低，58 只（81%）负荷高。大多数是小型犬（54/72；75%；29/72；40%吉娃娃犬），并且很可能患有 PH（67/72；93%）。色素尿是继嗜睡（32/72；44%）后第二常见的临床发现（31/72；43%）。贫血（37/55；36%）、色素尿（30/58；52%）和胆红素尿（28/36；78%）在高负荷心丝虫的犬中更为常见（P <.05）。根据贫血、色素尿和临床症状，72 只犬中有 18 只（25%）被认为患有 CS。
尽管大多数患有心内型心丝虫的犬心丝虫负荷高且 PH 可能性大，但只有 25%的犬有 CS 的临床证据。超声心动图是一种有用的工具，可用于识别心内型心丝虫，检测 PH 的可能性，并可用于对心内型心丝虫阳性的小型犬进行心内型心丝虫迁移的分期。
