Establishing a Non-invasive Method to Measure Heart Performance
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 发起方
- 入组人数
- 72
- 试验地点
- 2
- 主要终点
- Magnetic resonance measures of cardiac function
研究概览
简要总结
The purpose of the study is to evaluate a new way to examine cardiac function, using software developed at Caltech. The experimental device is software loaded on an iPhone. The iPhone is used to capture a pulse (waveform) by simply placing the iPhone lightly over the neck where the carotid pulse can be felt. In this study the information collected from the iPhone app is compared to cardiac function data obtained from the current gold standard for measuring cardiac function, cardiac magnetic resonance imaging (MRI). Subjects referred from cardiologists will also generally have echocardiography information available for comparison with the iPhone app. For the study, subjects will have completely non-invasive studies done in one setting: The iPhone app to capture the waveforms (over carotid and radial (wrist) arteries), tonometry (another non-invasive method using a modified stethoscope), standard pulse oximetry, followed by a 30 minute MRI examination of the heart. A second complete study will be done about 6 months after the first. The complete study session takes about 1.5 hours.
详细描述
Investigators at Caltech have developed an iPhone-based application that allows them to capture an arterial waveform using the iPhone camera held over the skin. Then based on the captured waveform and previous laboratory experiments and models, the investigators are able to calculate ejection fraction, the percentage of blood that goes out of the heart into the circulation with each beat. Previous studies suggested that the iPhone app measurements of ejection fraction were similar to those obtained with traditional cardiac echocardiography. In the current study the iPhone app measures are being compared to ejection fraction obtained using cardiac MRI. The iPhone also measures other physical properties of the heart and aorta that the investigators call "intrinsic frequencies". Using healthy subjects they have established the normal pattern/range of intrinsic frequencies, and in this study, a more diverse population of subjects (some with heart disease) will be studied, to determine how intrinsic frequency measures compare to traditional clinical measures of cardiac function.
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 90 Years（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •Adult age 18-90, outpatients
排除标准
- •Inability to lie flat for 30 minutes with periodic breath holding
- •Metal implants or other standard contraindications to MRI
- •Acute cardiac decompensation (active chest pain, shortness of breath)
- •Hypotension (SBP<90 mm Hg)
- •Claustrophobia
- •Patient too large to fit in closed MRI
结局指标
主要结局
Magnetic resonance measures of cardiac function
时间窗: Within 1 month of study
Standard end-points of cardiac function such as chamber size and relaxation.
次要结局
未报告次要终点
研究者
Marie Csete MD, PhD
Chief Scientific Officer
Huntington Medical Research Institutes