UCL logo

UCL Discovery

UCL home » Library Services » Electronic resources » UCL Discovery

Reversal of inappropriate peripheral vascular responses in hypertrophic cardiomyopathy

Thaman, R; Elliott, PM; Shah, JS; Mist, B; Williams, L; Murphy, RT; McKenna, WJ; (2005) Reversal of inappropriate peripheral vascular responses in hypertrophic cardiomyopathy. Journal of the American College of Cardiology , 46 (5) pp. 883-892. 10.1016/j.jacc.2005.05.053.

Full text not available from this repository.

Abstract

OBJECTIVES: We assessed the frequency of abnormal forearm vasodilator responses during lower body negative pressure (LBNP) in 21 non-obstructive hypertrophic cardiomyopathy (HCM) patients (31 ± 8 [20 to 43] years) with abnormal blood pressure response (ABPR) to exercise and the effects of three drugs used to treat vasovagal syncope (propranolol, clonidine, and paroxetine) in a double-blind crossover study. BACKGROUND: Some HCM patients have an ABPR to exercise, which may be due to paradoxical peripheral vasodilatation. A similar proportion has paradoxical forearm vasodilatation during central volume unloading using LBNP. These abnormal reflexes may be caused by left ventricular mechanoreceptor activation. Similar mechanisms may also contribute to some cases of vasovagal syncope. METHODS: Blood pressure changes were assessed during exercise, and forearm vascular responses and baroreceptor sensitivity were assessed during LBNP using plethysmography. RESULTS: Nine (43%) patients (group A) had paradoxical vasodilator responses (forearm vascular resistance [FVR] fell by 7.5 ± 4.6 U), and 12 (57%) patients (group B) had normal vasoconstrictor responses during LBNP (FVR increased by 7.7 ± 4.9 U). Paroxetine augmented systolic blood pressure (SBP) during exercise in group A (21 ± 6 mm Hg vs. 14 ± 11 mm Hg at baseline, p = 0.02); no effect was detected in group B. Paroxetine reversed paradoxical vascular responses during LBNP in seven (78%) patients from group A. Propranolol and clonidine had no significant effect on SBP during exercise but reversed paradoxical vascular responses in some patients from group A (n = 5 and n = 3). CONCLUSIONS: Paradoxical vasodilatation during LBNP occurs in 40% of patients with ABPR during exercise and is reversed by propranolol, clonidine, and paroxetine. Paroxetine also improved SBP response to exercise. © 2005 by the American College of Cardiology Foundation.

Type: Article
Title: Reversal of inappropriate peripheral vascular responses in hypertrophic cardiomyopathy
DOI: 10.1016/j.jacc.2005.05.053
UCL classification: UCL > Provost and Vice Provost Offices
UCL > Provost and Vice Provost Offices > School of Life and Medical Sciences
UCL > Provost and Vice Provost Offices > School of Life and Medical Sciences > Faculty of Pop Health Sciences > Institute of Cardiovascular Science
UCL > Provost and Vice Provost Offices > School of Life and Medical Sciences > Faculty of Pop Health Sciences > Institute of Cardiovascular Science > Clinical Science
URI: http://discovery.ucl.ac.uk/id/eprint/41319
Downloads since deposit
0Downloads
Download activity - last month
Download activity - last 12 months
Downloads by country - last 12 months

Archive Staff Only

View Item View Item