The Association between Obesity, Blood Pressure Variability, and Right Ventricular Function and Mechanics in Hypertensive Patients

Background: The purpose of this investigation was to evaluate the association between blood pressure (BP) variability and right ventricular (RV) mechanical function in normal-weight, overweight, and obese untreated patients with hypertension. Methods: This retrospective cross-sectional study included 127 untreated subjects with hypertension who underwent 24-hour ambulatory BP monitoring and complete two-dimensional and three-dimensional echocardiographic examination. All participants were divided into three groups according to body mass index (BMI): normal-weight patients (BMI <25 kg/m²), overweight patients (25 ≤ BMI <30 kg/m²), and obese patients (BMI ≥ 30 kg/m²). Results: Daytime, nighttime, and 24-hour BP variability parameters were higher in overweight and obese subjects with hypertension than in lean subjects. Two-dimensional RV longitudinal strain and systolic strain rate were significantly lower in obese patients with hypertension than in normal-weight patients (-24.1 ± 3% vs -23.3 ± 3.2% vs -21.7 ± 3.3%, P = .004). Three-dimensional echocardiographic RV volumes indexed to body surface area were lower in lean and overweight subjects than in obese participants with hypertension (mean RV end-diastolic volume index, 65 ± 6 vs 67 ± 7 vs 71 ± 8 mL/m², P = .001), while three-dimensional RV ejection fraction decreased in the same direction (60 ± 4% vs 58 ± 3% vs 57 ± 3%, P <.001). Nighttime BP variability indices, more than daytime BP variability parameters, correlated with two-dimensional RV global longitudinal strain and three-dimensional echocardiographic RV volumes. Conclusions: BP variability and RV structure, function, and mechanics are significantly affected by obesity in patients with untreated hypertension. BP variability is significantly associated with RV remodeling in patients with hypertension.