Mobile Thrombus in Sinuses of Valsalva in a 1-Year-Old-Cat: Case Report

Öz

Feline aortic thromboembolism is a life-threatening condition most commonly associated with cardiomyopathy and typically localised at the aortic trifurcation. Direct visualisation of a mobile thrombus within the aortic root prior to the development of clinical embolic signs has rarely been reported in cats. This case report describes the clinical course of a one-year-old male British Shorthair cat in which a mobile thrombus was detected at the level of the sinuses of Valsalva during echocardiographic examination before the onset of arterial thromboembolism. The cat was referred for respiratory distress following elective castration. Thoracic radiography revealed pulmonary oedema. Echocardiography demonstrated marked left atrial enlargement, borderline systolic function and a severe restrictive diastolic filling pattern consistent with a restrictive cardiomyopathy phenotype. A mobile thrombus was identified within the aortic root. Multimodal antithrombotic therapy, including low molecular weight heparin and rivaroxaban, was initiated. Despite treatment, clinical arterial thromboembolism affecting both pelvic limbs developed seven days later. Repeat echocardiography revealed resolution of the aortic thrombus but the presence of a new thrombus within the left atrium. Coagulation testing showed normal prothrombin time, shortened activated partial thromboplastin time and markedly increased fibrinogen concentration. The patient died six days after the embolic event. This case highlights the dynamic and unpredictable nature of thromboembolism in cats and suggests that mobile thrombi located within the aortic root may be associated with a poor prognosis, even in the absence of significant haemodynamic obstruction. Early detection and aggressive therapy may not always prevent embolisation of pre-existing thrombi, underscoring the limitations of current treatment strategies.

Anahtar Kelimeler

• cat
• thrombus
• embolism
• aorta

Sinus of Valsalva’da Mobil Trombüs: 1 Yaşında Bir Kedide Olgu Sunumu

Öz

Kedilerde aortik tromboembolizm, en sık kardiyomiyopati ile ilişkili olan ve genellikle aort trifurkasyonunda lokalize görülen, yaşamı tehdit eden bir klinik tablodur. Klinik embolik bulguların ortaya çıkmasından önce aort kökü içerisinde mobil bir trombüsün doğrudan görüntülenmesi ise nadiren bildirilmiştir. Bu olgu sunumunda, arteriyel tromboembolizm gelişmeden önce ekokardiyografik inceleme sırasında Valsalva sinüsleri düzeyinde mobil trombüs saptanan, bir yaşında erkek British Shorthair ırkı bir kedinin klinik seyri sunulmaktadır. Olgu, kastrasyon sonrası gelişen solunum sıkıntısı nedeniyle acil kliniliğine sevk edilmiştir. Hastanın toraks radyografisinde pulmoner ödem belirlenmiştir. Ekokardiyografik incelemede belirgin sol atriyal dilatasyon, sınırda sistolik fonksiyon ve restriktif kardiyomiyopati fenotipi ile uyumlu ileri derecede restriktif diyastolik dolum paterni saptanmıştır. Aort kökü içerisinde mobil karakterde bir trombüs görüntülenmiştir. Düşük molekül ağırlıklı heparin ve rivaroksabanı içeren multimodal antitrombotik tedavi başlatılmıştır. Ancak tedaviye rağmen yedi gün sonra her iki arka ekstremiteyi etkileyen klinik arteriyel tromboembolizm gelişmiştir. Kontrol ekokardiyografide aort içindeki trombüsün kaybolduğu, buna karşın sol atriyum içerisinde yeni bir trombüs oluştuğu belirlenmiştir. Koagülasyon analizlerinde protrombin zamanı referans aralığında bulunurken, aktive parsiyel tromboplastin zamanının kısalmış ve fibrinojen konsantrasyonunun belirgin şekilde artmış olduğu tespit edilmiştir. Hasta, embolik olaydan altı gün sonra kaybedilmiştir. Bu olgu, kedilerde tromboembolizmin dinamik ve öngörülemez doğasını ortaya koymakta; aort kökünde yerleşimli mobil trombüslerin, belirgin hemodinamik obstrüksiyon olmasa dahi, kötü prognoz ile ilişkili olabileceğini düşündürmektedir. Erken tanı ve agresif antitrombotik tedavi uygulamalarına rağmen mevcut trombüslerin embolizasyonu her zaman önlenememekte olup, bu durum güncel tedavi yaklaşımlarının sınırlılıklarını vurgulamaktadır.

Anahtar Kelimeler

• kedi
• trombüs
• emboli
• aorta

Kaynakça

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