P111 DISCREPANCY BETWEEN BRACHIAL AND INVASIVE INTRA-AORTIC PRESSURES IN PATIENTS UNDERGOING CARDIAC CATHETERIZATION

Abstract

Introduction: Invasive intra-aortic pressures are the gold standard for accurate Blood Pressure (BP) measurement. Hypertension management is guided by brachial cuff BP although its accuracy has been questioned. Hypothesis: We hypothesized that there may be a discrepancy between brachial and invasive intra-aortic BPs. Methods: Invasive intra-aortic and brachial cuff pressures were recorded in some 3000 patients undergoing coronary angiography (mean age 58.6 ± 28, 23% female) between 2010 and 2016, at King Abdul AzizCardiac Centre, Riyadh, Saudi Arabia. Clinical and angiographic data were collected from electronic medical records (Apollo Lx®). Results: Cuff brachial BP underestimated intra-aortic systolic BP (−6.2 mm Hg;95% CI:−7.2 to −5.4 mmHg; p < 0.0001),but overestimated intra-aortic diastolic BP (2.5 mm Hg; 95% CI:1.5 to 3.8 mm Hg;p < 0.001). The discrepancy betweenintra-aortic and brachial systolic BP was significantly higher in women than men ( −15 mm Hg; 95% CI: −14 to −17 mm Hg vs. −3.9 mm Hg;95% CI: −2.8 to −4.1 mm Hg, p < 0.0001). Intra-aortic diastolic BP was overestimated by cuff BP in men (0.9 mm Hg; 95% CI;0.74 to 1.26, p < 0.0.001) but underestimated in women ( −3.6 mm Hg;95% CI:−3 to −4 mm Hg, p < 0.0001). While brachial BP correctly estimated intra-aortic systolic BP in subjects <50 yr-olds ( 0.13 mm Hg; 95% CI:−0.57 to 0.85 mm Hg, p = 0.68),there was a large discrepancy in >50 yr-olds ( −8.6 mm Hg; 95% CI: −8.1 to −9.5 mm Hg, p < 0.0001). Conclusions: Brachial BP underestimates intra-aortic systolic BP, particularly in women, older subjects and at higher BPs with implications for HTN mangagement.