Ultrapower; a Minimally Invasive Tool for Evaluation of Total Cardiac Power

Study Overview
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Brief Summary
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The heart is essentially a hydraulic pump which ensures adequate delivery of blood through generating pressure and forward flow of blood. The energy delivered by the heart is uncommonly measured clinically, and todays gold standard involves placing a plastic catheter into the lung arteries. The investigators have developed an ultrasound based approach to calculate this energy without the need for catheters through the heart. This novel approach is called ultrapower. Ultrapower involves the instantaneous multiplication of the cardiac output and the arterial blood pressure. The study aims to use the ultrasound based approach to investigate Cardiac Power in the coronary artery bypass graft population.

Official Title
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Ultrapower, an In-house Developed System for Instantaneous Logging of Ultrasound Based Blood Flow, Blood Pressure and ECG.

Conditions
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Cardiac Diseases

Intervention / Treatment
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* Other: Comparison cardiac power and cardiac power output at different time points in the perioperative period


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: • coronary artery bypass graft operation Exclusion Criteria: Lack of informed consent Previous aortic valve replacement Inadequate Doppler signal on transthoracic echocardiography

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Diagnostic
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: Postoperative elective CABG patients<br>Patients included for coronary artery bypass graft (CABG) surgery, secondary to ischaemic heart disease. | Other: Comparison cardiac power and cardiac power output at different time points in the perioperative period<br>* The intervention is a comparison between two methods of calculating the heart's energy delivery, cardiac power, measured in watts. A tertiary measurement is calculation of arterioventricular coupling. All patients will have cardiac power output calculated through the use of Doppler echocardiography. The echocardiography based cardiac output will be done through the velocity time integral of the left ventricular outflow tract (LVOT). This will be compared against total power as measured by our Ultrapower approach which involves instantaneous doppler measurement of cardiac output through LVOT multiplied with simultaneous radial artery pressure. This and ejection fraction (for calculation of ventriculoarterial coupling) will be recorded at rest in neutral position preoperatively, directly post operatively and the day after operation. Directly postoperatively the power measurements will also be repeated in Trendelenburg and anti Trendelenburg position.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The hearts energy delivery per second measured in watts (Cardiac Power), using two established methods and the ultrapower method | Measured both as ultrapower and cardiac power output, both measured in watts and method of measurement described in intervention section | Immediately preoperatively | 
| The hearts energy delivery per second measured in watts (Cardiac Power), using two established methods and the ultrapower method |  | approximately 1 hour post operatively | 
| The hearts energy delivery per second measured in watts (Cardiac Power), using two established methods and the ultrapower method |  | 1 day after operation | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Hemodynamics, Echocardiography, Doppler, Pulsed