Non-bacterial thrombotic endocarditis (NBTE), formerly recognized as marantic endocarditis, represents a rare cardiovascular pathology intricately linked with hypercoagulable states, notably malignancy and autoimmune disorders. Characterized by the development of sterile vegetations comprised of fibrin and platelets on cardiac valves, NBTE poses a diagnostic challenge due to its resemblance to infective endocarditis. Therapeutic endeavours primarily revolve around addressing the underlying aetiology and instituting anticoagulant regimens to forestall embolic events, with surgical intervention seldom warranted. Non-bacterial thrombotic endocarditis frequently coexists with malignancies and autoimmune conditions, such as lupus and antiphospholipid antibody syndrome, and, more recently, has been associated with COVID-19. Its pathogenesis is underpinned by a complex interplay of endothelial dysfunction, hypercoagulability, hypoxia, and immune complex deposition. Clinical manifestations typically manifest as embolic phenomena, particularly cerebrovascular accidents, bearing substantial mortality rates. Diagnosis necessitates a high index of suspicion and meticulous exclusion of infective endocarditis, often facilitated by advanced cardiac imaging modalities. Anticoagulation, typically employing low molecular weight heparin or warfarin, constitutes the cornerstone of pharmacological intervention. Surgical recourse may be warranted in instances of refractory heart failure or recurrent embolic events. Given its multifaceted nature, the management of NBTE mandates a multidisciplinary approach, with prognosis contingent upon individual clinical intricacies. Future endeavours should prioritize further research to refine therapeutic strategies and enhance patient outcomes.

中文翻译：

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非细菌性血栓性心内膜炎：临床和病理生理学重新评估


非细菌性血栓性心内膜炎 （NBTE），以前被认为是马兰蒂性心内膜炎，是一种罕见的心血管病变，与高凝状态（尤其是恶性肿瘤和自身免疫性疾病）有着错综复杂的联系。NBTE 的特征是在心脏瓣膜上形成由纤维蛋白和血小板组成的无菌赘生物，由于其与感染性心内膜炎相似，因此带来了诊断挑战。治疗工作主要围绕解决潜在病因和制定抗凝方案以预防栓塞事件，很少需要手术干预。非细菌性血栓性心内膜炎经常与恶性肿瘤和自身免疫性疾病共存，例如狼疮和抗磷脂抗体综合征，最近还与 COVID-19 有关。其发病机制由内皮功能障碍、高凝状态、缺氧和免疫复合物沉积的复杂相互作用为基础。临床表现通常表现为栓塞现象，尤其是脑血管意外，死亡率很高。诊断需要高度怀疑并仔细排除感染性心内膜炎，这通常有助于先进的心脏影像学检查。抗凝治疗（通常使用低分子肝素或华法林）是药物干预的基石。在难治性心力衰竭或复发性栓塞事件的情况下，可能需要手术追索权。鉴于其多方面性，NBTE 的管理需要采用多学科方法，预后取决于个体临床复杂性。未来的努力应优先考虑进一步研究，以改进治疗策略并提高患者预后。