Evaluating Central Aortic Blood Pressures in a Tertiary South Indian Hospital

Background Of late, central aortic blood pressure (CABP) has emerged as a better parameter than peripheral blood pressure (BP) in the diagnosis of cardiovascular events. Advent of new technologies has facilitated the calculation of CABP from machine-derived peripheral BP. In this study, the author determined the differences between peripheral BP measured manually or by machine and machine-derived CABP and examined whether this difference is stable even after categorizing the sample pool based on sex, hypertension, diabetes status, and β-blocker use. Materials and Methods A total of 83 patients (both male and female) who attended the cardiology outpatient department were enrolled in the study. BP was recorded both manually and using Mobil-O-Graph pulse wave analyzer (ARC Solver) in the patient's sitting posture. The author compared the derived central, manual, and device-measured BP among the patient samples and assessed whether sex, hypertension, diabetes, and β-blocker use influence these differences. Results Among the study population, 28 were females and 55 were males; patients’ mean age was 59.97 ± 12.15 years. The mean peripheral systolic BP (SBP) and diastolic BP (DBP) measured manually were127.55 ± 20.15 and 79.73 ± 9.57 mm Hg, respectively. Similar measurements recorded by the device were 129.68 ± 19.93 and 78.92 ± 13.48, respectively. The derived mean central aortic SBP and DBP was 117.69 ± 17.78 and 80.15 ± 13.71, respectively. Statistically significant difference in the manual and central aortic SBP (9.85 ± 11.16; p < 0.0001) was observed. This difference was significant irrespective of sex, hypertension, diabetes status, and β-blocker use. Similarly, difference between machine-derived peripheral SBP and central aortic SBP was statistically significant (p < 0.0001). However, the difference in manual and central aortic DBP was nonsignificant (p = 0.6976). Interestingly, a small (−1.34 ± 2.28) but statistically significant difference (p < 0.0001) between machine-derived peripheral DBP and central aortic DBP was observed. Further analysis to find out effect of β-blocker use on CABP revealed that the central aortic SBP is slightly, but statistically significantly, lower in β-blocker users (117.7 ± 17.71; p < 0.0001) than that of β-blocker nonusers (118.9 ± 18.37; p< 0.0001). Conclusion Central aortic systolic pressure is statistically significantly lower than the manually recorded peripheral SBP irrespective of sex, hypertension, diabetes status, and β-blocker use. A small but significant difference was observed between machine-derived peripheral DBP and central aortic DBP. Patients using β-blockers were observed to have marginally lower CABP values than those who are not using them.