High-normal blood pressure, functional capacity and left heart mechanics: is there any connection?

OBJECTIVE: To evaluate the relationship between functional capacity and left ventricular (LV) and left atrial (LA) myocardial deformation, assessed by two- and three-dimensional (2DE and 3DE) strain analysis, in subjects with high-normal blood pressure (BP).

METHODS: This cross-sectional study included 64 subjects with optimal BP and 75 subjects with high-normal BP of similar gender and age. All the subjects underwent a complete 2DE and 3DE examination and cardiopulmonary exercise testing.

RESULTS: 3DE global longitudinal strain was significantly lower in the group with high-normal BP than in the optimal BP group (- 20.1 ± 2.4 vs - 18.5 ± 2.3%, p < 0.001). Similar results were obtained for 3DE global circumferential strain (- 21.8 ± 2.6 vs - 19.3 ± 2.4%, p < 0.001), as well as for 3DE global radial strain (45.1 ± 8.8 vs 42.3 ± 7.2%, p = 0.042), and 3DE global area strain (- 30.1 ± 4.2 vs - 28.1 ± 3.8%, p < 0.001). LV twist was similar between the observed groups, whereas untwisting rate was significantly decreased in the subjects with high-normal BP (- 123 ± 30 vs - 112 ± 26°/s, p = 0.023). Peak VO2 was significantly lower in the high-normal BP group (30.8 ± 4 vs 28.3 ± 3.7 ml/kg/min, p < 0.001). 2DE LV ejection fraction (β = 0.38, p = 0.014), 2DE global longitudinal strain (β = 0.35, p = 0.019) and 3DE global longitudinal strain (β = 0.27, p = 0.042) were independently associated with peak VO2.

CONCLUSION: LV and LA mechanics, as well as functional capacity are significantly impaired in the subjects with high-normal BP. LV and LA myocardial deformations are associated with peak oxygen uptake.