Systolic hypertension in critical aortic stenosis and the effect of valve replacement.

All cases of aortic valve replacement (AVR) for critical aortic stenosis (AS) in a 3 year period were reviewed and 43 cases were included in the study. Twenty patients had systolic hypertension preoperatively by sphygmomanometry and/or by measurement of central aortic pressure during cardiac catheterization. These patients also had a significantly higher mean left ventricular (LV) peak pressure than their normotensive counterparts. Following AVR all 43 patients were normotensive. This study suggests that not only can an elevated blood pressure (BP) be found in the presence of AS, but that AS itself can cause hypertension, in which case AVR can result in normalization of BP. We suggest that the systolic hypertension is due to a partial transmission of the higher LV peak pressure across the aortic valve, despite the stenotic valve acting as a pressure barrier. This effect may be more pronounced the tighter the stenosis.