Impacto da Etiologia sobre a Função Atrial Esquerda em Pacientescom Refluxo Mitral Importante

A adaptacao a sobrecarga cronica de volume na insuficiencia mitral (IM) tende a aumentar o atrioesquerdo (AE), predispondo a disfuncao atrial e arritmias. Embora as dimensoes do AE tragam importante informacao prognostica, a funcao contratil atrial nao tem sido estudada consistentemente na IM. Objetivo: O objetivo deste estudo foi analisar a funcao atrial em pacientes com IM por cardiopatia reumatica (CR) eprolapso valvar mitral (PVM). Metodos: Foram estudados 54 pacientes com IM importante, com area do orificio regorgitante efetivo (ERO) ≥ 0,40 cm2,sendo 23 com CR e 31 com PVM, em ritmo sinusal, com fracao de ejecao do ventriculo esquerdo (VE) > 60%. Foram medidos diâmetros e massa do VE, volumes do VE e AE (maximo, minimo e pre-A), fracao de esvaziamento total (FEsv.TAE), passiva (FEsv.P AE) e ativa (FEsv.A AE) do AE, para avaliar funcao. Medidas de Doppler transmitral e tecidual foram obtidas. Resultados: Comparados ao PVM, pacientes com CR eram mais jovens (35 ± 11 versus 55 ± 13 anos; p Adaptation to chronic volume overload in patients with mitral insufficiency (MI) tends to increase left atrium (LA), leading to LA dysfunction and arrhythmias. Though LA dimension is a well-known cardiovascular risk predictor, LA contractile function has not been thoroughly assessed in patients with MI of distinct etiologies. Objective: We aimed to assess LA structure and function in patients with MI due to rheumatic heart disease (RHD) and mitral valve prolapse (MVP). Methods: We assessed 54 patients with severe MI, defined by an effective regurgitant orifice (ERO) ≥ 0.40 cm2, 23 with RHD and 31 with MVP, all in sinus rhythm and with left ventricular (LV) ejection fraction > 60%. We measured LV diameters and mass, and also volumes (Simpson) to assess function, including maximal, minimal and pre-atrial contraction volumes, and total (TLAEF), passive (PLAEF) and active (ALAEF) LAemptying fraction. Transmitral and tissue Doppler measurements were obtained. Results: Compared to MVP, patients with RHD were younger (35 ± 11 versus 55 ± 13 years) and mainly female (17 versus 7 female; p