Low Flow Low Gradient Aortic Stenosis Relevance of the (re)Search for a Contractile Reserve

Status

Completed

Phases

Unknown

Study type

Observational

Source

ClinicalTrials.gov

Registry ID

NCT02727504

Acronym

LOWAS

Enrollment

Registered

2016-04-04

Start date

2016-05-11

Completion date

2020-01-06

Last updated

2020-02-07

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

Conditions

Aortic Valve Stenosis

Keywords

Aortic valve stenosis, low flow, dobutamine stress echocardiography

Brief summary

Investigators sought to demonstrate that the increase in the stroke volume during a dobutamine stress echocardiography might impact the prognosis of a patient addressed for a low flow low gradient suspected severe aortic valve stenosis.

Interventions

DEVICEElectrocardiogram

ECG at inclusion and M12

DEVICE2D and 3D echocardiography

2D and 3D echocardiography at inclusion and M12

DEVICEDobutamine stress echocardiography

dobutamine stress echocardiography at inclusion

BIOLOGICALBlood tests

Blood test electrolytes, creatinine, hemoglobin, NT-proBNP, CRP, ST-2 at inclusion and M12

DEVICECardiac MRI

Cardiac MRI at inclusion

DEVICECardiac scanner

Cardiac scanner at inclusion

OTHER6-minutes walking test

6-minutes walking test at inclusion and M12

OTHERDuke Activity Score

Duke Activity Score at inclusion and M12

Study design

Observational model

COHORT

Time perspective

PROSPECTIVE

Eligibility

Sex/Gender

ALL

Age

45 Years to 90 Years

Healthy volunteers

Inclusion criteria

* Patient from 45 to 90 years old * Patient agreeing freely to participate in the study * Aortic surface area suspected to be \< 1 cm² or \< 0.6 cms²/m² * Low aortic gradient defined by a mean pressure gradient \< 40 mmHg * Aortic low flow defined by: a stroke volume indexed \< 35 ml/m2 * Any contra-indication for the realization of the MRI

Exclusion criteria

* Heart rhythm disorders * Presence of comorbidity altering the 2-year prognosis of a patient (cancer, terminal renal insufficiency (GFR 30 ml / min / 1,73m2), liver cirrhosis, respiratory insufficiency (VEMS 1 L) * Presence of a concomitant valvular heart disease with stenosis or regurgitation \> moderated * Persons subject to major legal protection (safeguarding justice, guardianship, trusteeship), persons deprived of liberty

Design outcomes

Primary

Measure	Time frame
Number of death of all cause	Month 12
Number of emergent hospitalization for any cardiovascular reason	Month 12

Secondary

Measure	Time frame	Description
Death (all causes)	12 months	—
Emergency Cardiovascular hospitalization	12 months	—
Change in left ventricular ejection fraction (LVEF), in global longitudinal strain in 2D and or 3D echocardiography	Inclusion, 12 months	—
Symptoms evolution	Inclusion, 12 months	6-minute walking test

Countries

France

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026