Optimal Antihypertensive Level for Improvement of Coronary Microvascular Dysfunction
Mizuno R et al. – The findings indicate that lowering blood pressure to a normal level is necessary to improve coronary microvascular dysfunction in hypertensive patients. Furthermore, raising diastolic blood pressure to a higher level within normal range has the most beneficial effect. However, as this study is based on observational design, it may have several limitations.Methods
- The authors prospectively studied 108 untreated hypertensive patients.
- All patients were treated with antihypertensive agents for approximately 12 months.
- Coronary flow reserve (CFR) was measured before and after treatment.
- The patients were divided into hypertensive, prehypertensive, and normal groups based on their average blood pressure during the treatment period.
- Pretreatment CFR was similar among all groups.
- CFR increased significantly in the normal group during the treatment period, but decreased significantly in the prehypertensive and hypertensive groups.
- This decrease was significantly greater in the hypertensive group than in the prehypertensive group.
- Multivariate analysis showed lowering blood pressure to normal level to be an independent determinant of improvement in CFR.
- The normal group was divided into normal–higher and normal–lower subgroups based on their average diastolic blood pressure during the treatment period.
- Increase in CFR was significantly greater in the normal–higher group than in the normal–lower group.