Effect of the exercise training on breathing pattern evaluated by chemorreflexes and ergoreflexes in heart failure patients

• Grant number: 06/03910-4
• Support Opportunities: Regular Research Grants
• Start date: November 01, 2006
• End date: October 31, 2009
• Field of knowledge: Biological Sciences - Physiology - Physiology of Effort
• Principal Investigator: Guilherme Veiga Guimarães
• Grantee: Guilherme Veiga Guimarães
• Host Institution: Faculdade de Medicina (FM). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

Exercise intolerance has been related to the alterations from hemodynamics and neurohumoral systems by complex interaction between cardioreflexes in heart failure (HF). The central, peripheral chemorreflexes and ergoreflexes are thought to be responsible for hyperventilation at rest and exercise, contributing to dyspnea. This breathing pattern would be elicits changes in types fibers from the respiratory muscles, contributing to the impairment of the respiratory muscles. We hypothesized that exercise training program contributes to the attenuation of cardioreflexes, which modifies breathing pattern and improving respiratory muscle performance during exercise. OBJECTIVE: To evaluate the central, peripheral chemoreflexes and ergoreflex hyperactivity and to relate to the alterations in breathing pattern and respiratory muscles performance during exercise, beyond to evaluate the effects of the physical training program on the breathing pattern caused by attenuated cardioreflexes. METHODOLOGY: 30 patients of both sex with age between 20 and 70 years, LVEF ≤40% and NYHA functional class I, II and III; and 14 normal subjects will be study. They will be divided in: Group 1(n=20) HF training, Group 2(n=10) HF control, Group 3(n=7) normal subjects training and Group 4(n=7) normal subjects control. All subjects will be assessment by cardiopulmonary test, spirometry, maximal inspiratory pressure, respiratory cycle, P0.1, pulmonary impedance, noninvasive tension-time index, endothelial function, 6-walk test with central and peripheral chemorecepor and ergoreceptor sensibilization. They are going to include in the physical training program for three months. Then, they are going to evaluated again at the end of the study. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

FERNANDES SILVA, MIGUEL MORITA; BACAL, FERNANDO; ROQUE, JEAN MARCELO; TEIXEIRA-NETO, IRAM SOARES; CARVAS JUNIOR, NELSON; BOCCHI, EDIMAR ALCIDES; GUIMARAES, GUILHERME VEIGA. Age-Related Maximum Heart Rate Among Ischemic and Nonischemic Heart Failure Patients Receiving beta-Blockade Therapy. JOURNAL OF CARDIAC FAILURE, v. 18, n. 11, p. 831-836, NOV 2012. (06/03910-4)