Romito G, Mazzoldi C, Di Benedetto M, Sabattini S
Department of Veterinary Medical Sciences, Alma Mater Studiorum - University of Bologna, via Tolara di Sopra 50, 40064 Ozzano dell'Emilia, Italy.
Department of Veterinary Medical Sciences, Alma Mater Studiorum - University of Bologna, via Tolara di Sopra 50, 40064 Ozzano dell'Emilia, Italy.
J Vet Cardiol. 2025 Jun;59:93-97. doi: 10.1016/j.jvc.2025.03.009. Epub 2025 Apr 4.
An 11-year-old Cavalier King Charles spaniel with a previous diagnosis of preclinical myxomatous mitral valve disease (MMVD) was presented with respiratory distress and abdominal distension. Lung edema and ascites were diagnosed. Echocardiography revealed a progression of the MMVD as it was associated with a moderate enlargement of the left-sided cardiac chambers and an atrial septal defect (ASD). The latter was hypothesized to be primarily due to a rupture of the interatrial septum caused by MMVD. Moreover, a hyperechoic irregular mass was documented inside the left atrium. At that time, the primary differential diagnosis included intracardiac thrombosis (ICT) and mural endocarditis. Comprehensive diagnostic tests subsequently ruled out extracardiac prothrombotic triggers; moreover, both blood and urine cultures tested negative. Despite the administration of cardiac and supportive therapies (including antithrombotic drugs), the dog died 138 days after presentation. Necropsy confirmed the presence of MMVD (type IV lesions according to Pomerance and Whitney's classification system) associated with remodeling of the left-sided cardiac chambers, multiple left atrial (LA) jet lesions, and ASD. Endocarditis was ruled out, and the LA mass was demonstrated to be an ICT entrapped in the ASD. In light of premortem and postmortem findings, the turbulent blood flow secondary to the mitral valve insufficiency and ASD, along with the extensive LA endothelial damage, were considered likely triggering factors for the development of ICT. This case suggests that, although ICT represents an extremely rare complication of cardiac diseases in dogs, it can potentially develop when canine MMVD is particularly advanced.
一只11岁的查理士王小猎犬，此前被诊断为临床前期黏液瘤性二尖瓣疾病（MMVD），现出现呼吸窘迫和腹部膨隆症状。诊断为肺水肿和腹水。超声心动图显示MMVD病情进展，伴有左侧心腔中度扩大和房间隔缺损（ASD）。推测后者主要是由MMVD导致的房间隔破裂引起。此外，在左心房内发现一个高回声不规则肿块。当时，主要鉴别诊断包括心内血栓形成（ICT）和壁层心内膜炎。综合诊断检查随后排除了心外促血栓形成诱因；此外，血液和尿液培养结果均为阴性。尽管给予了心脏和支持性治疗（包括抗血栓药物），这只狗在就诊后138天死亡。尸检证实存在MMVD（根据Pomerance和Whitney分类系统为IV型病变），伴有左侧心腔重塑、多个左心房（LA）喷射性病变和ASD。排除了心内膜炎，LA肿块被证实是一个被困在ASD中的ICT。根据生前和死后检查结果，二尖瓣关闭不全和ASD继发的湍流血液，以及广泛的LA内皮损伤，被认为可能是ICT发生的触发因素。该病例表明，尽管ICT是犬类心脏疾病极其罕见的并发症，但当犬类MMVD特别严重时，它有可能发生。
