Middle aortic syndrome coexisting with rheumatic mitral valve disease

Abstract

Middle aortic syndrome (MAS) is a rare clinical condition generated by segmental narrowing of the abdominal or distal descending thoracic aorta. Although rarely diagnosed and reported, it is a cause of hypertension in the middle aged. Its coexistence with rheumatic mitral valve disease is yet to be documented in the English literature. A 25-year-old female who had previously been managed as a hypertensive presented with difficulty with breathing, NYHA class II, and generalized body weakness, more in the lower limbs. General examination was normal. Her vitals were as follows: temperature- 98.5°F, pulse rate - 100/min, blood pressure (BP) - 160/100 mmHg (left upper limb), respiratory rate - 20/min, saturation - 100% on room air. Echocardiography revealed a thickened aortic valve, concentric left ventricular hypertrophy, thickened and prolapsed anterior mitral leaflet, thickened and fixed posterior mitral leaflet, severe mitral regurgitation, dilated left chambers, severe tricuspid regurgitation, and severe pulmonary artery hypertension (PAH, RVSP = 82 mmHg). She was scheduled for mitral valve replacement (MVR) and tricuspid valve repair. The diagnosis of surgical hypertension was missed. As a routine protocol in our institution, radial and femoral cannulation was done for invasive BP monitoring. Following such cannulation, radio-femoral pressure gradient was noted, with a suspicion of aortic coarctation, necessitating the need to defer the surgery. On further evaluation, computed tomography (CT) chest and CT angiography were suggestive of MAS extending from T8 to T11 thoracic vertebrae, with narrow-lumen proximal abdominal aorta. She subsequently had aorto-aortic bypass + MVR + tricuspid valve sutural annuloplasty via median sternotomy + laparotomy for definitive treatment. MAS is a rare vascular disorder. Of more rarity is its coexistence with rheumatic valvular disease complicated by severe PAH. With standard institutional protocols of evaluation, and a high index of suspicion, a missed diagnosis can be forestalled.