Successful treatment of hypertension accounts for improvements in markers of diastolic function - a pilot study comparing hydrochlorothiazide-based and amlodipine-based treatment strategies

Abstract

Background: There is controversy regarding whether blood pressure (BP) medications have relevant therapeutic benefits beyond those due to lowering of BP.

Objective: To show that rapid successful treatment of hypertension leads to improvement in cardiac morphology and function regardless of the pharmacological agents used.

Methods: Hypertension was defined as an average 24 h ambulatory BP of higher than 135/85 mmHg in 38 subjects with a mean (+/- SD) age of 54+/-7 years. Patients were randomly assigned to treatment with a diuretic based (n=20) or a calcium channel blocker (CCB)-based (n=18) medication. All subjects were followed every two weeks, and similar additional medications were added until the BP was lower than 125/80 mmHg, then followed monthly for a total of six months. Echocardiography with tissue Doppler imaging was performed, and was repeated after six months of aggressive pharmacotherapy and lifestyle management.

Results: Baseline ambulatory BP monitoring and echocardiographic measures of diastolic function were similar between both treatment groups. Subjects received 3.5+/-1 pills and 11+/-2 follow-up visits. The average 24 h BP was reduced from 145/91 mmHg to 124/75 mmHg (P<0.001) in the CCB group. A greater lowering from 143/91 mmHg to 117/72 mmHg occurred in the diuretic group (P=0.02 for the difference between groups) at six months. There was significant improvement in tissue Doppler imaging diastolic function parameters in both groups, with a trend toward greater improvement in the diuretic group. The left ventricular mass/ height(2.7) index decreased from 40 g/m(2.7) to 37 g/m(2.7) in the diuretic group (P=0.02), whereas a nonsignificant change (41 g/m(2.7) to 42 g/m(2.7)) occurred in the CCB group.

Conclusions: Aggressive BP lowering is associated with improved left ventricular diastolic function and mass proportional to the extent of BP normalization.

Figures

Figure 1)

Treatment scheme in randomized subjects. α Alpha; β Beta; ABPM Ambulatory blood pressure monitoring; ACEI Angiotensinconverting enzyme inhibitor; ARB Angiotensin receptor blocker; BP Blood pressure; CCB Calcium channel blocker; HCTZ Hydrochlorthiazide; mo Months; PRN pro re nata (as needed); q Every

Figure 2)

Recruitment process. ABPM Ambulatory blood pressure monitoring; BP Blood pressure; CCB Calcium channel blocker; Echo Echocardiography; HCTZ Hydrochlorothiazide

Figure 3)

Blood pressure changes in individual subjects, presented in mmHg. The only patient who failed to improve from baseline to six months in the hydrochlorothiazide (HCTZ) group was noncompliant because of a job change to the night shift and a variable sleep schedule. ABPM Ambulatory blood pressure monitoring; CCB Calcium channel blocker