Severe Rheumatic Mitral Stenosis With Multivalvular Abnormalities in a British-Born Adult Without a Recognized History of Acute Rheumatic Fever

Rheumatic heart disease (RHD) has become uncommon in the United Kingdom, particularly among British-born adults without a recognized history of acute rheumatic fever (ARF). A 40-year-old British-born female with no previously diagnosed cardiac disease presented with a one-year history of progressive exertional dyspnoea. Chest radiography demonstrated cardiomegaly, and the N-terminal pro-B-type natriuretic peptide concentration was 1,800 pg/mL. Transthoracic echocardiography showed very severe mitral stenosis with characteristic rheumatic morphology, a mitral valve area of 0.33 cm² by planimetry, and a mean transmitral gradient of 16.6 mmHg. Associated findings included mild mitral regurgitation, tricuspid valve abnormalities with moderate-to-severe tricuspid regurgitation, and discordant aortic valve findings consistent with a low-flow, low-gradient pattern of aortic stenosis, an estimated pulmonary artery systolic pressure of approximately 105-110 mmHg, left ventricular systolic impairment, and impaired right ventricular longitudinal systolic function. Following transoesophageal echocardiography, cardiac magnetic resonance imaging, and multidisciplinary review, the patient underwent mitral and aortic valve replacement with tricuspid valve repair. This case highlights that advanced RHD can present without a documented history of ARF and emphasizes the importance of valve morphology, integrated haemodynamic assessment, and timely multidisciplinary management.