Department of Cardiology, Mackay Base Hospital, Queensland, Australia.
James Cook University, Queensland, Australia.
BMC Cardiovasc Disord. 2023 Jun 26;23(1):324. doi: 10.1186/s12872-023-03359-9.
Coronary embolism is a relatively rare but important non-atherosclerotic cause of acute coronary syndrome, mainly caused by atrial fibrillation and mechanical heart valve thrombosis due to subtherapeutic anticoagulation. There have been increasing reports of bioprosthetic valve thrombosis (BPVT), but thromboembolic events are rare and mainly affect the cerebrovascular system. Coronary embolism is an extremely rare complication of BPVT.
A 64-year-old male presented with non-ST-Elevation myocardial infarction (NSTEMI) to an Australian regional health service. Three years ago, he had undergone Bentall procedure with bioprosthetic aortic valve replacement for severe aortic regurgitation and significant aortic root dilatation. Diagnostic coronary angiography revealed embolic occlusion of first diagonal branch in the absence of underlying atherosclerosis. Prior to NSTEMI presentation, the patient was clinically asymptomatic apart from the progressive increase in transaortic mean pressure gradient on transthoracic echocardiography which was first detected seven months after surgical aortic valve replacement. Transoesophageal echocardiography showed restrictions of the aortic leaflet opening but no evidence of mass or vegetation. After eight weeks of warfarin therapy, the raised aortic valve gradient returned to normal. Lifelong warfarin was prescribed, and patient remained clinically well at 39-month follow-up.
We experienced a case of coronary embolism in a patient with probable BPVT. Reversible bioprosthetic valve hemodynamic deterioration after anticoagulation strongly supports the diagnosis in the absence of histopathology. Early moderate-to-severe hemodynamic valve deterioration warrants further investigations, including cardiac computed tomography and sequential echocardiography, to investigate for probable BPVT and consideration of timely anticoagulation initiation to prevent thromboembolic events.
冠状动脉栓塞是一种相对罕见但重要的非动脉粥样硬化性急性冠状动脉综合征病因，主要由抗凝治疗不足导致的心房颤动和机械心脏瓣膜血栓形成引起。越来越多的生物瓣血栓形成（BPVT）的报告，但血栓栓塞事件很少见，主要影响脑血管系统。冠状动脉栓塞是 BPVT 的一种极其罕见的并发症。
一名 64 岁男性因非 ST 段抬高型心肌梗死（NSTEMI）到澳大利亚地区卫生服务机构就诊。三年前，他因严重主动脉瓣反流和明显主动脉根部扩张而行 Bentall 手术，用生物瓣置换主动脉瓣。诊断性冠状动脉造影显示第一对角支有栓塞性闭塞，无潜在动脉粥样硬化。在 NSTEMI 发作前，患者除经胸超声心动图检测到手术后七个月起跨主动脉平均压力梯度逐渐升高外，无任何临床症状。经食管超声心动图显示主动脉瓣叶开口受限，但无肿块或赘生物的证据。华法林治疗八周后，升高的主动脉瓣梯度恢复正常。患者被开处终身华法林，并在 39 个月的随访中保持临床良好。
我们遇到了一例可能为 BPVT 的患者发生冠状动脉栓塞。抗凝后生物瓣血流动力学恶化是可逆的，在没有组织病理学的情况下强烈支持该诊断。早期中重度血流动力学瓣膜恶化需要进一步检查，包括心脏计算机断层扫描和连续超声心动图，以调查可能的 BPVT 并考虑及时开始抗凝以预防血栓栓塞事件。
