Behcet’s Disease: An Uncommon Cause of Severe Tricuspid Stenosis

Acquired tricuspid stenosis (TS) is an uncommon valvular abnormality. Rheumatic heart disease is the most common cause of TS. However, this condition may also be caused by other disorders such as vasculitis, hypereosinophilic syndrome, carcinoid syndrome, non-bacterial thrombotic endocarditis, and infective endocarditis [9]. Our patient presented with severe TS secondary to BD associated with a pulmonary artery aneurysm, intra-atrial thrombus, and significant endomyocardial fibrosis. Cardiac involvement of BD is rare and is usually associated with poor prognosis. Abnormalities that can occur include pericarditis, myocarditis, coronary arteritis, endomyocardial fibrosis, intracardiac thrombosis, and non-bacterial thrombotic endocarditis [7]. Aortic regurgitation is the most common valvopathy associated with BD. TS caused by BD is extremely rare [8]. Our patient may have had a variant of BD known as Hughes-Stovin Syndrome (HSS), which classically affects young men and typically presents with dyspnea, chest pain, and signs of pulmonary hypertension following a history of deep venous thrombosis. Cardiac thrombi, particularly in the right ventricle, remain a rare manifestation of HSS [10,11]. The pathophysiology of TS caused by BD is yet to be understood. Exclusion of other TS causes, such as cardiac rheumatic disease can be challenging. Most cases of tricuspid rheumatic disease present with tricuspid regurgitation or a combination of regurgitation and stenosis; pure TS is very uncommon. Rheumatic tricuspid disease almost never occurs as an isolated lesion and is nearly always associated with mitral valve disease and, in some cases, aortic valve disease [12]. Our patient had no past medical history of rheumatic disease, and the other cardiac valves were normal. In this case, the TS is most likely caused by thrombus formation, inflammation, and resulting fibrosis, as described in MRI findings and noted in intraoperative findings. TS is generally diagnosed by transthoracic echocardiogram (TTE). The diagnosis of TS is based on identifying the following combination of echocardiographic abnormalities [13]: thickened tricuspid valve leaflets with limited mobility; high velocity turbulent diastolic flow through the tricuspid valve; and prolonged pressure half-time. Our patient had clear signs of TS on the TTE associated with persistent symptoms of right heart failure. There is no single laboratory test that can diagnose BD. Even the histopathological findings are not specific. In 2014, the International Team for the Revision of the International Criteria for BD (ICBD) proposed criteria that were derived from a multinational database. For the ICBD criteria, ocular lesions, oral aphthosis and genital aphthosis are each assigned 2 points, while skin lesions, central nervous system involvement, and vascular manifestations are assigned 1 point each. The pathergy test, when used, is assigned 1 point. A patient scoring ≥4 points is classified as having BD. Our patient scored 6 points [7]. Limited data is available to guide the treatment of TS, especially when it is caused by BD vasculitis. A series of cases of treatment of aortic regurgitation associated with BD have been reported, and they might serve as a reference [14,15]. Most patients with aortic regurgitation and BD need valve replacement surgery. Severe complications such as dehiscence of the prosthetic valve, perivalvular leakage, false aneurysm at the cannulation site, dehiscence of the sternotomy site, and death have been reported [14,15]. In a single-center study, using biological immunosuppressors might be effective and well-tolerated for the perioperative management of severe and refractory aortic regurgitation caused by BD [16]. In the study of 20 patients, Sun reported a significant reduction in postoperative perivalvular leak occurrence. Despite being on infliximab for 16 months, our patient experienced severe dehiscence of the biological prosthesis during surgery, which prevented the surgeon from properly anchoring the device. Our patient presented with another rare cardiovascular condition not related to his TS: the right lower lobar pulmonary artery aneurysm. This setting has no clear guidelines for the best approach to managing pulmonary aneurysms. Aneurysms ≥ 5.5 cm or symptomatic aneurysms seem to benefit from surgical treatment. However, in cases like ours where there is aneurysmatic dilatation secondary to vasculitis, immunosuppressor therapy should be considered as definitive treatment before a surgical approach. Our patient did have a complete resolution of his right lower lobar pulmonary artery aneurysm after his treatment with immunosuppressant therapy [17]. It is unclear if the discontinuation of anticoagulation due to hemoptysis posed a significant management challenge in this case. The early cessation of anticoagulation may have contributed to its progression. This likely led to thrombus organization and fibrosis, ultimately resulting in tricuspid stenosis. This report shows the complexity of the diagnostic and therapeutic approach to BD with severe TS and pulmonary artery aneurysm. The optimal treatment of TS in BD is still unknown. Immunosuppressant therapy alone has the potential to resolve the aneurysmatic dilatation of the pulmonary artery. However, it seems to have little effect on reverting the severity of TS caused by BD [16]. Diuretic therapy may help with the management of systemic edema, but the mechanical issue should be addressed by surgical intervention. The surgical team, patients, and patients’ families should be aware of the high risk of complications.