Reflex responses of venous capacitance vessels in patients with hypertrophic cardiomyopathy

Thomson, H L, Morris-Thurgood, J, Atherton, J, McKenna, W J and Frenneaux, M P (1998) Reflex responses of venous capacitance vessels in patients with hypertrophic cardiomyopathy. Clinical Science, 94 (4). pp. 339-46. ISSN 0143-5221

Full text not available from this repository.

Abstract

1. The aim of this study was to determine if there is impaired reflex venoconstriction in patients with hypertrophic cardiomyopathy and whether this is related to a history of syncope or exercise hypotension. 2. Thirty percent of patients with hypertrophic cardiomyopathy have exercise-induced hypotension associated with a failure of arteriolar constriction. Impaired venoconstriction could exacerbate this situation. 3. We evaluated 43 patients with hypertrophic cardiomyopathy and 24 controls. Nuclear venous plethysmography was used to measure forearm venous capacitance during lower body negative pressure, splenic venous volume changes during bicycle exercise and blood pressure responses to treadmill exercise. We assessed any association between abnormal reflex venous control and a history of syncope and exercise hypotension. 4. The percentage reduction in unstressed forearm venous volume during lower body negative pressure was similar in patients and controls (8.9 +/- 7.1% versus 9.7 +/- 5.9%, P not significant). Patients with a history of syncope demonstrated a less marked percentage reduction in volume than those without (-2.1 +/- 6.9% versus -10.6 +/- 6.0%, P = 0.001). In three patients with a history of syncope there was a paradoxical increase in forearm venous volume during lower body negative pressure. During exercise there was a substantially smaller decrease in splenic venous volume in patients compared with controls (-20.1 +/- 14.0% and -42.6 +/- 12.6% respectively, P = 0.0001). Furthermore, there was an association between attenuated splenic venoconstriction or venodilation and exercise hypotension in patients (P = 0.005). 5. Abnormal reflex control of venous capacitance beds in patients with hypertrophic cardiomyopathy was associated with both syncope and exercise hypotension.

Item Type:	Article
Uncontrolled Keywords:	adult,blood volume,cardiomyopathy, hypertrophic,exercise,female,forearm,humans,hypotension,lower body negative pressure,male,middle aged,plethysmography,reflex,spleen,syncope,vascular capacitance,vascular resistance
Faculty \ School:	Faculty of Medicine and Health Sciences > Norwich Medical School
UEA Research Groups:	Faculty of Medicine and Health Sciences > Research Groups > Cardiovascular and Metabolic Health
Depositing User:	Pure Connector
Date Deposited:	09 Mar 2015 07:27
Last Modified:	22 Apr 2023 22:31
URI:	https://ueaeprints.uea.ac.uk/id/eprint/52391
DOI:

Actions (login required)

View Item