The natural history of mitral stenosis.

The relationship between hemodynamic abnormalities and disability was studied with paired cardiac catheterizations nine to 69 months apart in ten patients with mitral stenosis. Left atrial and pulmonary arterial pressures and pulmonary vascular resistance increased in each patient; however, there was no consistent relationship between the progression of symptoms and the palmonary vascular resistance. Changes in disability were most closely related to changes in puhnonary arterial and left atrial pressures. Comparable hemodynamic changes between studies also occurred during exercise. These data document the long-suspected relationship between progressive hemodynamic abnormalities and disability in patients with mitral stenosis.