Diagnostic Impact of Low-dose Dobutamine Echocardiography in Low-flow Low-gradient Aortic Stenosis
试验速览
- 阶段
- 不适用
- 入组人数
- 150
- 试验地点
- 1
- 主要终点
- Factors associated with flow-reserve
研究概览
简要总结
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.
研究设计
- 研究类型
- Observational
- 观察模型
- Cohort
- 时间视角
- Prospective
入排标准
- 年龄范围
- 18 Years 至 —（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •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.
- •Age > 18 years.
- •Signed informed consent.
排除标准
- •Other moderate-severe valvular heart disease.
- •Unwilling to participate in the study.
- •Poor echocardiographic window.
- •Inability to follow-up due to temporary citizenship Registration Number (CPR-Number) or emigration within the study period.
- •Pregnant women.
- •Patients with severe chronic renal failure (eGFR<40 ml/min) will not undergo cardiac MRi or CT angiography.
- •Known contrast allergy.
结局指标
主要结局
Factors associated with flow-reserve
时间窗: Dobutamine infusion, up to 30 minutes
f) Association with outcomes (rate of AVR, hospitalization for cardiac failure, death).
The ability of LDDE to predict outcome in patients with paradoxical low-flow, low-gradient aortic stenosis.
时间窗: 1 day til 3 years
Cardiovascular mortality
Adverse effects during Dobutamine infusion
时间窗: Dobutamine infusion, up to 30 minutes
1. 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. 2. 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).
次要结局
未报告次要终点
研究者
Nils Sofus Borg Mogensen
Doctor
Odense University Hospital