The Effects of Dobutamine on Postoperative Cardiac Function in Aortic Valve Replacement

Study Overview
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Brief Summary
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The use of dobutamine in postoperative hemodynamic treatment is widespread despite seemingly intact contraction of the heart. This study aims to elucidate the efficacy of low-dose dobutamine infusion in patients in the postoperative phase replacement of the aortic valve.

Official Title
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The Effects of Dobutamine on Postoperative Systolic Deformation and Diastolic Function in Patients With Hypertrophic Cardiomyopathy Operated for Aortic Valve Stenosis

Conditions
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Heart Failure

Intervention / Treatment
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* Drug: Dobutamine


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: 18-90 years Left ventricular posterior wall =/>12mm Ejection fraction > 45% Sinus rhythm Eligible for aortic valve replacement Exclusion Criteria: Need for concomitant cardiac bypass operation. Moderate or severe insufficiency of the mitral valve Active endocarditis Insufficient ultrasound window Using B-blockers Liver insufficiency Patients treated with COMT-inhibitors Allergy towards dobutamine Pregnancy Women of fertile age who do not use relevant anti-conception Lacking participant consent

Ages Eligible for Study
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Minimum Age: 19 Years
Maximum Age: 90 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: Treatment
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Dobutamine<br> | Drug: Dobutamine<br>* 90 minutes of infusion 5 ug/kg/minute followed by isotonic saline for the same duration. The sequence of the above is randomized<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Cardiac output | Change in cardiac output (l/min) from initiation of study drug or placebo until 90 minutes of infusion. | From 0 to 90 minutes after drug initiation | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Mean pulmonary artery pressure | Changes in pulmonary artery pressure (mmHg) from start of study drug or placebo infusion until 90 minutes after the start. | From 0 to 90 minutes after drug initiation. | 
| Echocardiography | Echocardiographic measures of systolic and diastolic heart function. | From 0 minutes to 90 minutes after drug initiation | 
| Changes in mixed venous saturation | Changes in mixed venous saturation (in per cent) from baseline until the end of dobutrex or placebo infusion. | From 0 minutes to 90 minutes after drug initiation | 
| norepinephrine requirement | The amount of norepinephrinem(mg) required to maintain adequate systemic blood pressure during the infusion period of dobutrex and placebo | From 0 minutes to 90 minutes after drug initiation | 
| Central venous pressure | Changes in CVP from baseline until 90 minutes of study drug or placebo infusion. | From 0 minutes to 90 minutes after drug initiation | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Postoperative, Dobutamine, Inotropes, Stunning, Heart failure