Technical difficulties have been reported by some users of the search function and is being investigated by technical staff. Thank you for your patience and apologies for any inconvenience caused.

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been endorsed by the ANZCTR. Before participating in a study, talk to your health care provider and refer to this information for consumers
Trial registered on ANZCTR


Registration number
ACTRN12610000559011
Ethics application status
Approved
Date submitted
6/07/2010
Date registered
12/07/2010
Date last updated
12/07/2010
Type of registration
Retrospectively registered

Titles & IDs
Public title
Left-ventricular function and autonomic cardiac responses after short-term inpatient cardiac rehabilitation: A prospective clinical trial
Scientific title
Left-ventricular function and autonomic cardiac responses after short-term inpatient cardiac rehabilitation following coronary artery bypass graft (CABG) surgery: A prospective clinical trial
Secondary ID [1] 252162 0
no secondary IDs
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Patients with left ventricular function normal or reduced undergoing coronary artery bypass graft (CABG) and cardiac rehabilitation (CR) 257702 0
Condition category
Condition code
Physical Medicine / Rehabilitation 257874 257874 0 0
Physiotherapy
Cardiovascular 257891 257891 0 0
Other cardiovascular diseases

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Patients awaiting first-time CABG were invited to participate in the study, and enrolled after giving written informed consent. Participants were divided into left ventricular function (LVF) normal group (LVFN group) or left ventricular function (LVF) reduced group (LVFR group). Pre-operatively, the patient’s age, gender, weight, height, body mass index, risk factors, pharmacological treatment and other relevant medical history were documented. Additionally, a pulmonary function test was performed to investigate the presence of chronic obstructive pulmonary disease (COPD) and education about the effects of surgery on cardiorespiratory function, post-operative routines and cardiac rehabilitation programme were provided. Post-operatively, surgical and hospital data were recorded and all patients were engaged in cardiac rehabilitation supervised by one of three members of physiotherapy staff, specifically trained.
All patients participated in a once-daily individual short-term supervised inpatient physiotherapy exercise protocol consisted of early mobilization plus respiratory exercises with approximate duration of daily physiotherapy sessions of 60 minutes per day starting on the first postoperative day until discharge Briefly, this protocol consisted of progressive exercises, range of movement (ROM) active-assistive movements to climbing flights of stairs. Estimated energy expenditure during this program was initially set at approximately 2 metabolic equivalent (MET)s and progressed to 4 METs. Exercise intensity was gauged by heart rate with an upper threshold set at standing resting heart rate +20bpm, monitored by a Polar S810i telemetry system.
Moreover, the patients performed voluntary deep-breathing exercises from functional residual capacity to total lung capacity (40 deep breaths in four sets of 10, each breath included a 5 second hold at end inspiration) followed by coughs or huffs (with wound support) supervised once daily. Patients were instructed to perform these breathing and coughing exercises independently every waking hour.
The outcome measures of heart rate (HR) and R-R intervals (R-Ri) were collected prior (pre-operative and first post-operative day - PO1) and after (day before discharge) to cardiac rehabilitation.
Intervention code [1] 256757 0
Rehabilitation
Comparator / control treatment
Participants were divided into left ventricular function normal group (LVFN group) composed of patients with left ventricular ejection fraction (LVEF) equal to 55.0% or LVF reduced group (LVFR group) composed of patients with left ventricular function between 35.0-54.0% regarded as moderately and mildly abnormal LVF. All patients participated in a similar once-daily short-term supervised inpatient physiotherapy exercise protocol consisted of early mobilization plus respiratory exercises starting on the first postoperative day until discharge.
Control group
Uncontrolled

Outcomes
Primary outcome [1] 258738 0
Primary outcome measure was non-linear heart rate variability (HRV) indexes (approximate entropy and correlation dimension) after a short-term inpatient supervised physiotherapy protocol.
The heart rate and R-R intervals used to obtain measures of heart rate variability were registered continuously using a Polar S810i telemetry system
Timepoint [1] 258738 0
day before discharge (pre-discharge)
Secondary outcome [1] 264787 0
As a secondary outcome measure we analyzed heart rate variability (HRV) indexes in traditional time domain measures (SD2 and RR tri index) after a short-term inpatient supervised physiotherapy protocol. The heart rate and R-R intervals used to obtain measures of heart rate variability were registered continuously using a Polar S810i telemetry system
Timepoint [1] 264787 0
day before discharge (pre-discharge)

Eligibility
Key inclusion criteria
Patients undergoing first-time elective CABG surgery with LVF normal or reduced were included in this study
Minimum age
42 Years
Maximum age
70 Years
Sex
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
Exclusion criteria were emergent or concomitant surgery, recent myocardial infarction (MI) (6 months), implanted pacemaker, unstable angina, chronic disturbances in heart rhythm, significant acute arrhythmias, valvular heart diseases, COPD, severe non-cardiac diseases and the inability to perform cardiac rehabilitation according to our protocol.

Study design
Purpose of the study
Treatment
Allocation to intervention
Non-randomised trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Participants were divided into left ventricular function (LVF) normal group (LVFN group) composed of patients with left ventricular ejection fraction (LVEF) equal to 55.0% or LVF reduced group (LVFR group) composed of patients with LVEF between 35.0-54.0% regarded as moderately and mildly abnormal LVF
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?



Intervention assignment
Other design features
Phase
Type of endpoint/s
Statistical methods / analysis

Recruitment
Recruitment status
Completed
Date of first participant enrolment
Anticipated
Actual
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
Actual
Sample size
Target
Accrual to date
Final
Recruitment outside Australia
Country [1] 2744 0
Brazil
State/province [1] 2744 0
Sao Paulo

Funding & Sponsors
Funding source category [1] 257251 0
University
Name [1] 257251 0
Universidade Federal de Sao Carlos
Country [1] 257251 0
Brazil
Primary sponsor type
Individual
Name
Renata Goncalves Mendes
Address
Laboratorio de Fisioterapia Cardiorrespiratoria, Nucleo de Pesquisa em Exercicio Fisico (NUPEF), Rodovia Washington Luis (SP-310), km 235, Sao Carlos - Sao Paulo. CEP 13565-905.
Country
Brazil
Secondary sponsor category [1] 256494 0
Individual
Name [1] 256494 0
Audrey Borghi e Silva
Address [1] 256494 0
Laboratorio de Fisioterapia Cardiorrespiratoria, Nucleo de Pesquisa em Exercicio Fisico (NUPEF), Rodovia Washington Luis (SP-310), km 235, Sao Carlos - Sao Paulo. CEP 13565-905.
Country [1] 256494 0
Brazil

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 259270 0
Ethics Committee of Federal University of Sao Carlos
Ethics committee address [1] 259270 0
Rodovia Washington Luis (SP-310), km 235, Sao Carlos - Sao Paulo. CEP 13565-905.
Ethics committee country [1] 259270 0
Brazil
Date submitted for ethics approval [1] 259270 0
Approval date [1] 259270 0
Ethics approval number [1] 259270 0

Summary
Brief summary
It is known that coronary artery bypass graft (CABG) leads to cardiac autonomic (CA) dysfunction and that cardiac rehabilitation (CR) involving physical exercise is associated with CA benefits. However, is not known whether differences in left ventricular function (LVF) interfere in CA responses after CR. The aim of this study was to assess the CA responses in normal and reduced LVF patients undergoing CABG and CR. The hypothesis of this study was that patients with the poorest LVF are likely to derive the greatest benefit in the cardiac autonomic activity from rehabilitation.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 31366 0
Address 31366 0
Country 31366 0
Phone 31366 0
Fax 31366 0
Email 31366 0
Contact person for public queries
Name 14613 0
Renata Goncalves Mendes
Address 14613 0
Laboratorio de Fisioterapia Cardiorrespiratoria, Nucleo de Pesquisa em Exercicio Fisico (NUPEF), Rodovia Washington Luis (SP-310), km 235, Sao Carlos - Sao Paulo. CEP 13565-905.
Country 14613 0
Brazil
Phone 14613 0
(+55 16) 3351-8705
Fax 14613 0
Email 14613 0
mendesrg@hotmail.com
Contact person for scientific queries
Name 5541 0
Audrey Borghi-Silva
Address 5541 0
Laboratorio de Fisioterapia Cardiorrespiratoria, Nucleo de Pesquisa em Exercicio Fisico (NUPEF), Rodovia Washington Luis (SP-310), km 235, Sao Carlos - Sao Paulo. CEP 13565-905.
Country 5541 0
Brazil
Phone 5541 0
(+55 16) 3351-8705
Fax 5541 0
Email 5541 0
audrey@ufscar.br

No information has been provided regarding IPD availability


What supporting documents are/will be available?

No Supporting Document Provided



Results publications and other study-related documents

Documents added manually
No documents have been uploaded by study researchers.

Documents added automatically
No additional documents have been identified.