Italian Multicenter PROject on Echo Assessment of Left VEntricular (IMPROVE) Dyssynchrony Study
试验速览
- 阶段
- 不适用
- 发起方
- 入组人数
- 336
- 试验地点
- 1
- 主要终点
- Prediction of the combined end-point defined as NYHA class improvement by at least one grade and echocardiographic left ventricular end-systolic volume decrease by at least 10% with respect to baseline (variations are considered as relative values);
研究概览
简要总结
Background. Clinical benefits of cardiac resynchronization therapy (CRT) have been clearly demonstrated in heart failure (HF) patients with severe left ventricular (LV) dysfunction and wide QRS at surface electrocardiogram. However, there is a growing evidence that QRS duration poorly predicts responses to CRT, and that ~30% of patients do not experience any benefit from CRT when pre-implant dyssynchrony is defined according to electrocardiographic criteria. A number of echocardiographic criteria have been proposed to assess mechanical LV dyssynchrony, but at present there is no consensus on their use to predict response to CRT.
Study Design. The Italian Multicenter PROject on echo assessment of left VEntricular (IMPROVE) dyssynchrony study is a prospective, multicenter, observational study aimed to assess feasibility and predictive power of mechanical dyssynchrony assessed by echocardiography in consecutive consenting patients candidate to CRT by clinical and electrocardiographic criteria. IMPROVE will enroll 120 healthy subjects and 216 HF patients in 6 sites in Italy. CRT response criteria will be based on improvement in NYHA class and LV reverse remodeling evaluated by 3D-echocardiography. Enrollment is expected to conclude early 2009.
Implications. CRT is today part of the therapeutic armamentarium for symptomatic HF patients refractory to medical therapy, with wide QRS complex and severe LV systolic dysfunction. The IMPROVE study has been designed to evaluate reference values of indexes of ultrasound mechanical dyssynchrony that have been proposed in the literature and compare their ability to predict response to CRT in HF patients.
详细描述
The IMPROVE study has 3 main purposes:
- definition of reference values of echocardiographic mechanical dyssynchrony (DYS) indexes in a population of healthy subjects;
- definition of the feasibility and reproducibility of such indexes in healthy subjects and in HF patients undergoing implantation of a biventricular pacemaker;
- definition of the accuracy of such indexes for predicting response to CRT.
STUDY DESIGN. Multicenter, prospective, observational study that will be carried out in 6 Italian sites of acknowledged expertise in LV DYS evaluation and biventricular pacemaker implantation. At least 120 healthy subjects (about 20 per site) and 216 HF patients candidates to CRT (about 36 per site) will be enrolled. With this sample volume it is possible to test statistically significative differences of about 7%, with an alfa=0.05 and beta=0.50. Definition of healthy subject includes absence of history and symptoms of any cardiovascular disease, normal physical examination and ECG. The same commercial ultrasound equipment will be used for image acquisition in each investigating center and echo studies will be sent to a core-lab for analysis.
Both ischemic and non ischemic etiology of HF will be considered. Patients with permanent or persistent atrial fibrillation or flutter will be excluded, as these patients cannot benefit from the atrial-ventricular component of resynchronization.
The following evaluations:
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
- 是
入选标准
- •Age > 18 years.
- •Sinus rhythm.
- •Chronic heart failure (>6 weeks duration) refractory to maximized drug therapy.
- •NYHA class III-IV.
- •LV ejection fraction less than 35% by RT3DE.
- •Indexed LV end-diastolic diameter >3.2 cm/m2 by 2D echocardiography and/or indexed end-diastolic volume >75 ml/m2 by 3D echocardiography.
排除标准
- •Hypertrophic, restrictive, obstructive cardiomyopathy.
- •Primitive and hemodynamically significant valve disease (defined as valvular stenosis greater than mild, and 3+ or 4+/4+ valvular regurgitations).
- •Constrictive pericarditis.
- •Primitive pulmonary hypertension.
- •Uncorrected congential heart disease.
- •Patients candidate to heart surgery.
- •Patients with acute myocardial infarction, severe unstable angina and stroke that occurred within 6 weeks prior the study enrollment.
- •Patients with life expectation <1 year due to disease unrelated to the heart failure.
- •Pregnant women.
- •Refusal to give the informed consent.
结局指标
主要结局
Prediction of the combined end-point defined as NYHA class improvement by at least one grade and echocardiographic left ventricular end-systolic volume decrease by at least 10% with respect to baseline (variations are considered as relative values);
时间窗: 3 months after biventricular pace-maker implant
次要结局
- Feasibility and repeatibility of echocardiographic indexes of intraventricular dyssynchrony(6 months)
- definition of reference values of echocardiographic mechanical dyssynchrony indexes in a population of healthy subjects;(12 months)