Positive effects of aggressive vasodilator treatment of well-treated essential hypertensive patients

• Published in: Journal of human hypertension Vol. 30; no. 11; pp. 690 - 696
• Main Authors: Engholm, M, Mulvany, M J, Eftekhari, A, Mathiassen, O N, Buus, N H, Christensen, K L
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 01-11-2016; Nature Publishing Group
• Subjects: 631/443/1338/243; 631/443/1338/2729; 692/699/75/243; 692/699/75/593; Adult; Aged; Aged, 80 and over; Angiotensin; Angiotensin II; Angiotensin II Type 1 Receptor Blockers - adverse effects; Angiotensin II Type 1 Receptor Blockers - therapeutic use; Angiotensin-Converting Enzyme Inhibitors - adverse effects; Angiotensin-Converting Enzyme Inhibitors - therapeutic use; Antihypertensive Agents - adverse effects; Antihypertensive Agents - therapeutic use; Antihypertensives; Blood flow; Blood pressure; Blood Pressure - drug effects; Calcium Channel Blockers - adverse effects; Calcium Channel Blockers - therapeutic use; Coronary artery disease; Coronary Circulation - drug effects; Doppler effect; Dosage and administration; Drug therapy; Drug Therapy, Combination; Echocardiography; Echocardiography, Doppler; Epidemiology; Essential hypertension; Essential Hypertension - diagnosis; Essential Hypertension - drug therapy; Essential Hypertension - physiopathology; Female; Forearm; Forearm - blood supply; Health Administration; Humans; Hypertension; Male; Medicine; Medicine & Public Health; Microcirculation - drug effects; Microvasculature; Middle Aged; Occlusion; original-article; Patient outcomes; Patients; Plethysmography; Prospective Studies; Public Health; Risk factors; Time Factors; Treatment Outcome; Vascular Resistance - drug effects; Vasodilation - drug effects; Vasodilator agents; Vasodilator Agents - adverse effects; Vasodilator Agents - therapeutic use; Vasodilators; Denmark
• ISSN: 0950-9240; 1476-5527
• DOI: 10.1038/jhh.2016.13

Increased systemic vascular resistance and coronary microvascular dysfunction are well-documented in essential hypertension (EH). We investigated the effect of additional vasodilating treatment on coronary and peripheral resistance circulation in EH patients with high systemic vascular resistance index (SVRI) despite well-treated blood pressure (BP). We enroled patients on stable antihypertensive treatment that were given intensified vasodilating therapy (ACE inhibitor, angiotensin II receptor blocker or calcium channel blocker). Before and following 6 months of intensified therapy, coronary resting and maximal artery flow were measured by transthoracic Doppler echocardiography to calculate coronary flow reserve (CFR) and minimum vascular resistance (C-R
min
). Cardiac output was estimated by inert gas rebreathing to calculate SVRI. Maximal forearm blood flow was determined by venous occlusion plethysmography to calculate minimum vascular resistance (F-R
min
). Patients were assigned into two groups: high-SVRI and low-SVRI subgroups, based on a median split at baseline. Following additional treatment SVRI decreased more in the high-SVRI group than in the low-SVRI group (14.4 vs −2.2%:
P
=0.003), despite similar baseline ambulatory BP (132/81 mm Hg) and BP reduction (6.5 and 4.6%:
P
=0.19). F-R
min
remained unchanged (6.5 vs −2.0%:
P
=0.30), while C-R
min
decreased by 22 and 24% (
P
=0.80) and CFR increased by 23 and 17% (
P
=0.16). Thus, intensified vasodilating therapy improved SVRI more in patients with high SVRI than in those with low SVRI. Regardless of SVRI status, the treatment improved cardiac but not forearm dilatation capacity. The substantial improvement of the hypertensive cardiac microvascular dysfunction was not related to the reduction in SVRI.