Diagnostic Impact of Low-dose Dobutamine Echocardiography in Low-flow Low-gradient Aortic Stenosis

Aortic Valve Stenosis Clinical Trial

— DALLAS  

Official title:

Diagnostic Impact of Low-dose Dobutamine Echocardiography in Low-flow Low-gradient Aortic Stenosis

Clinical Trial Details — Status: Recruiting

Administrative data

• NCT number: NCT05015829
• Other study ID #: S-20190058
• Secondary ID: 19/34844
• Status: Recruiting
• Start date: September 1, 2019
• Est. completion date: August 31, 2022

Study information

• Verified date: August 2021
• Source: Odense University Hospital
• Contact: Nils Mogensen, MD
• Phone: 61286371
• Email: nils.sofus.borg.mogensen[@]rsyd.dk
• Is FDA regulated: No
• Study type: Observational

Clinical Trial Summary

When aortic valve-area is <1.0cm2 and transvalvular mean-gradient is >40mmHg, the diagnosis of severe aortic stenosis (AS) is straightforward. However, some patients present with an apparently reduced valve-area, despite transvalvular-gradient <40mmHg; Low-flow, low-gradient aortic stenosis (LFLG AS). When a patient with LFLG AS also presents with LVEF <50%, guidelines recommends performing a Low-Dose Dobutamine-echocardiography (LDDE) to confirm true-severe AS. However, nearly 30% of patients with LFLG AS do not show an adequate respond to Dobutamine. More commonly, patients present with the combination of LFLG AS, despite LVEF≥50%. In this group of patients the use of LDDE remains undisclosed.

The purpose of this study is to examine the safety and diagnostic usefulness of LDDE in patients with LFLG AS with LVEF≥50%. Furthermore we will examine factors associated with inadequate response to LDDE.

150 symptomatic and/or asymptomatic patients with LFLG and LVEF≥50% and a control group with LVEF<50% will be enrolled at the Department of Cardiology, OUH. Patients will undergo clinical evaluation including LDDE, blood analyses, CT-scan and cardiac Mri.

Only a limited number of studies examine the possible use of LDDE in patients with LFLG AS and LVEF≥50% and no study has been performed documenting the safety and feasibility.

Recruitment information / eligibility

• Status: Recruiting
• Enrollment: 150
• Est. completion date: August 31, 2022
• Est. primary completion date: September 1, 2021
• Gender: All
• Age group: 18 Years and older

Eligibility

Inclusion Criteria:

1. Low-flow (SVi<35 ml/m2) low-gradient (mean gradient <40 mmHg) AS with estimated AVA<1.0 cm2 referred to the Department of Cardiology, Odense University Hospital.

2. Age > 18 years.

3. Signed informed consent.

Exclusion Criteria:

1. Other moderate-severe valvular heart disease.

2. Unwilling to participate in the study.

3. Poor echocardiographic window.

4. Inability to follow-up due to temporary citizenship Registration Number (CPR-Number) or emigration within the study period.

5. Pregnant women.

6. Patients with severe chronic renal failure (eGFR<40 ml/min) will not undergo cardiac MRi or CT angiography.

7. Known contrast allergy.

Related Conditions & MeSH terms

• Aortic Valve Stenosis
• Constriction, Pathologic
• Heart Diseases
• Heart Valve Diseases
• Valvular Heart Disease
• Valvular Stenosis

Intervention

Diagnostic Test:
• Dobutamine Stress Echocardiography
Change in echocardiographic 2D and doppler measurements during infusion with Dobutamine 5 µg/kg/min till max dosage of 20 µg/kg/min.

Locations

Country	Name	City	State
Denmark	Odense University Hospital	Odense	Fune

Sponsors (3)

Lead Sponsor	Collaborator
Odense University Hospital	Region of Southern Denmark, University of Southern Denmark

Country where clinical trial is conducted

Denmark, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Adverse effects during Dobutamine infusion	The occurrence of angina pectoris, severely high systolic blood pressure >200 mmHg or ventricular premature beats Lown Grade >3 or supra-ventricular arrhythmias or tachycardia assessed by ECG.; Occurrence of signs of echocardiographic subvalvular obstruction; (systolic anterior motion of the mitral leaflet (SAM), high velocities (>2 m/sec) in the LV outflow tract and late peaking systolic jet).	Dobutamine infusion, up to 30 minutes
Primary	Factors associated with flow-reserve	a) Gender (male/female).	Dobutamine infusion, up to 30 minutes
Primary	Factors associated with flow-reserve	b) Aortic valve calcification assessed by cardiac CT (AU).	Dobutamine infusion, up to 30 minutes
Primary	Factors associated with flow-reserve	c) Myocardial fibrosis assessed by MRi (%).	Dobutamine infusion, up to 30 minutes
Primary	Factors associated with flow-reserve	d) Baseline myocardial systolic and diastolic function estimated by echocardiography (Global Longitudinal Strain (%), Strain Ratesystolic (SRs), deceleration time of mitral E-wave (ms) and end-systolic wall-stress corrected LVEF (dynes).	Dobutamine infusion, up to 30 minutes
Primary	Factors associated with flow-reserve	e) The ongoing use of beta-blockers (%, dosis).	Dobutamine infusion, up to 30 minutes
Primary	Factors associated with flow-reserve	f) Association with outcomes (rate of AVR, hospitalization for cardiac failure, death).	Dobutamine infusion, up to 30 minutes
Primary	The ability of LDDE to predict outcome in patients with paradoxical low-flow, low-gradient aortic stenosis.	Rate of AVR	1 day til 3 years
Primary	The ability of LDDE to predict outcome in patients with paradoxical low-flow, low-gradient aortic stenosis.	Hospitalization for cardiac failure	1 day til 3 years
Primary	The ability of LDDE to predict outcome in patients with paradoxical low-flow, low-gradient aortic stenosis.	All-cause mortality	1 day til 3 years
Primary	The ability of LDDE to predict outcome in patients with paradoxical low-flow, low-gradient aortic stenosis.	Cardiovascular mortality	1 day til 3 years