The Impact of Altered Arterioventricular Coupling on Central Cardiovascular Energy Delivery

Status

Completed

Phases

Unknown

Study type

Observational

Source

ClinicalTrials.gov

Registry ID

NCT03656757

Enrollment

Registered

2018-09-04

Start date

2019-01-02

Completion date

2019-03-13

Last updated

2019-03-21

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Cardiovascular Diseases

Keywords

Cardiac Power, Oscillatory Power, Coronary Artery Bypass Graft, Arterioventricular Coupling

Brief summary

This study will assess the amount of energy that the heart will deliver to the central circulation and the efficiency of that energy transfer, in patients undergoing a coronary artery bypass graft operation. Measurements will be taken just after induction of anaesthesia and repeated just after the end of the operation. The total energy delivered by the heart will be calculated by multiplying a pressure curve from the artery in the hand with the instantaneous ultrasound recorded cardiac output flow curve. The energy responsible for the acceleration of the blood volume, known as oscillatory power will also be calculated. The energy transfer will be calculated using a mathematical model based upon other ultrasound and blood pressure recorded variables. We would like to see if any alteration in energy delivered is in part due to impairment in energy transfer or alteration of fraction of oscillatory power rather than a change in total energy production. We would also like to study if there are changes in the oscillatory power after cardiac bypass surgery. The patients will be sampled sequentially into the study. We are not aware of any such studies undertaken in humans previously.

Interventions

None listed

Study design

Observational model

COHORT

Time perspective

PROSPECTIVE

Eligibility

Sex/Gender

ALL

Age

18 Years to No maximum

Healthy volunteers

Inclusion criteria

* Elective Coronary Artery Bypass Graft patients * No contraindications to transoesophageal Echo * Ejection fraction 40% or over

Exclusion criteria

* Lack of consent * Emergency operation * Prosthetic aortic valve

Design outcomes

Primary

Measure	Time frame	Description
Arterioventricular coupling	1 day	The ratio between arterial elastance and ventricular elastance
Total Cardiac Power	1 day	The amount of energy per second delivered from the left ventricle to the arterial circulation
Oscillatory Cardiac Power	1 day	The part of total cardiac power which is responsible for acceleration of the blood volume during systole.

Secondary

Measure	Time frame	Description
Cardiac Output	1 day	The hearts delivery of volume per minute
Heart rate	1 day	The amount of heart beats per minute
Systemic vascular resistance	1 day	The resistance to flow of the arterial tree

Countries

Norway

Outcome results