Central Aortic Pressure, Arterial Compliance: Emerging Tools to Identify and Guide Therapy for High-Risk African American Patients

Abstract

African Americans have signifi cantly higher burden of hypertension and associated cardiovascular morbidity and mortality [ 1 ]. About 30 % of deaths in African Americans are attributable to hypertension [ 2 ]. Peripheral brachial BP by conventional sphygmomanometry has remained the gold standard for measuring BP for over a century. Elevated peripheral brachial BP has been recognized as a major risk factor for cardiovascular disease (CVD), and reduction of peripheral brachial BP has been shown to reduce cardiovascular events [ 3 ]. However, peripheral brachial BP does not always refl ect the central aortic BP, which is intuitively more relevant for the pathogenesis of CVDs. While the mean and diastolic BP remain almost constant from the aortic root to peripheral brachial artery, the systolic BP and pulse pressure (the difference between the systolic and diastolic BP) are amplifi ed from the aortic root to the peripheral brachial artery with increasing distance. The amplifi cation of systolic and pulse BP is mainly a function of the timing and magnitude of wave refl ections and can be profoundly affected by many factors including age, gender, height, heart rate, aortic stiffness, and antihypertensive medications. Central aortic BP and arterial compliance can now be assessed using noninvasive applanation tonometry [ 4 , 5 ]. Emerging data suggest that measurements of central aortic BP and arterial compliance are better and more robust predictors of cardiovascular outcomes than traditional peripheral brachial BP [ 6 ]. Measuring central aortic BP and arterial compliance will likely become an increasingly important part of routine clinical assessment of BP and related cardiovascular risks and treatment effects, especially in high-risk African Americans.