Noninvasive Estimation of End-Systolic Aortic Pressure in Children


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To simplify the estimation of end-systolic aortic pressure (Pes) noninvasively, a regression equation was derived from intra-arterial measurements. Peak-systolic (Pps), Pes, and diastolic aortic pressure (Pd), pulse pressure (Pp), heart rate, hemoglobin, body weight, and height were measured. Cardiac index and body surface area were calculated in 66 patients (17 with aortic runoff lesions, group I; 49 without lesions, group II) with various heart diseases without aortic stenosis (35 males, 31 females, mean age 4.6 years) during the course of diagnostic catheterization. Using a stepwise regression analysis, the following relationship was determined from the combined groups: Pes= 0.422*Pps+ 0.617*Pd+ 1.377. The correlation between Pes measured directly and Pes calculated from our formula was quite strong(r= 0.957, P= 0.0001), as was the correlations between each subgroup (r= 0.948, group I; r= 0.959, group II). The correlation between Pes calculated and that estimated using an indirect carotid pulse tracing method was also strong (r= 0.912, P= 0.0001, n= 31). This regression equation appears applicable to infants or children with aortic runoff lesions in whom it is difficult to measure Pes by noninvasive methods using the carotid pulse. (ECHOCARDIOGRAPHY, Volume 8, September 1991)