The Changes of Noninvasive Hemodynamic Parameters after Device-Guided Slow Breathing Exercise in Hypertensive Patients

ABSTRACT

BACKGROUND: The device-guided breathing (DGB) exercise is a non-pharmacological treatment of high blood pressure (BP). Changes in hemodynamic variables after DGB remain to be defined. This study evaluated the hemodynamic effects of DGB in hypertensive patients. METHODS: Fifty-nine hypertensive individuals (male, 56%; age, 44 +/- 10 years) with systolic BP (SBP) in the range of 140 to169 mm Hg and diastolic BP (DBP) < 105 mm Hg were divided into two group: control group (n = 17) vs. DGB group (n = 42) who slowed respiratory rate by using 15 minutes daily DBG (RESPeRATE) over 8 weeks. Heart rate, BP and hemodynamic parameters including cardiac index (CI), thoracic fluid content (TFC), systemic vascular resistance index (SVRI) and total arterial compliance index (TACI) were measured using the ICG Monitor (CardioDynamics) at baseline and study end. RESULTS: Baseline characteristics were not different between the two groups. Office BP (SBP/DBP) was reduced from baseline to end value by 13.2 +/- 11.1/6.9 +/- 7.5 mm Hg in DGB group and 2.2 +/- 6.9/0.5 +/- 6.6 mm Hg in control group (p = 0.001, p = 0.004, respectively). Heart rate, CI, stroke index, and TFC were not changed in both groups. However, the SVRI was lower and the TACI was higher in DGB group than control group (SVRI: 2,728 +/- 599 vs. 3,141 +/- 714 dyne sec m2/cm5, p = 0.002; TACI: 0.845 +/- 0.194 vs. 0.761 +/- 0.184 mm Hg/mL/m2, p = 0.041). CONCLUSIONS: Daily device-guided breathing exercise for 8 weeks lowers the BP mediated by reducing the systemic vascular resistance and increasing the total arterial compliance without changes in heart rate and CI.