The Kinocardiograph for assessment of fluid status in patients with heart failure

Chronic heart failure (CHF) is a common cardiac condition with a high morbidity and mortality. CHF is often associated with episodes of acute decompensated heart failure (ADHF) which may lead to hospital admissions. This in turn leads to an impaired quality of life and also a major economic burden. Telemonitoring can contribute to early detection of ADHF, thereby providing early intervention which may reduce the patients' disease burden. Traditionally, telemonitoring in CHF consists of monitoring vital parameters (such as weight, blood pressure, heart rate), and physical complaints related to CHF. However these parameters change relatively late in the cascade of pathophysiological events leading to ADHF. Therefore there is a need for monitoring of additional parameters, preferably ones that changes earlier in this cascade. This can be achieved by invasive monitoring of pulmonary atery pressure or parameters derived from ICD's. Non-invasive monitoring of parameters closely related to hemodynamic state and cardiac filling pressures are not available yet.

Therefore the aim of the present study to evaluate whether changes in cardiac kinetic energy (KE), measured with a non-obtrusive, non-invasive device (Kinocardiograph (KCG)), are related to changes in fluid status in patients with acute decompensated heart failure.

The KCG consists of 2 small micro-electrical-mechanical-system (MEMS) accelerometers which are attached to the body with ECG patches. One sensor is placed on the sternum and measured seismocardiographic signals, and the other sensor is placed on the lower back, measuring ballistocardiographic signals. These can be translated to cardiac kinetic energy.

Changes in cardiac KE are correlated with changes in volume status in patients with acute decompensated heart failure.

Daily measurements are performed:
1. A 90 second KE measurement, with the KCG
2. Diameter and percentage collapse of the IVC, with echocardiography.

Both measurements are performed within a patient on a daily basis. The measurements start at hospital admission for ADHF and are continued until discharge from the hospital (which is decided by the cardiologist at the ward). Therefore the number of measurements will vary for each participant, depending on the number of days admitted to the hospital.

Patients who meet the inclusion criteria are asked by the doctor on the emergency department, whether they give permission to be contacted in person by the coordinating investigator. Subsequently the investigator will provide the patient with verbal and written information about the study. The patient will be asked to make a decision about participation within 24 hours, because iv diuretic therapy will start directly after admission.

If a patients consents to participate, he will receive usual treatment for ADHF (with iv diuretics). During admission daily study related measurements will follow. These measurements consist of a 90 seconds KCG reading to determine cardiac KE, and a measurement of the diameter and percentage collapse of the inferior vena cava (IVC) with echocardiography, to determine fluid status.

The study is finished when the patient is compensated and discharged from the hospital. This decision is made by the cardiologist at the cardiology ward. The amount of study related measurement will thus depend on the number of days admitted to the hospital.