Heart failure occurs when the heart muscle is weakened and cannot pump enough blood to meet the body’s needs.
Amongst the possible reasons for the development of heart failure, cardiomyopathy and Left Ventricular dysfunction are commonly observed.
Heart failure and high blood pressure
With a high blood pressure, the heart has to work harder to push blood round the body. To cope with this extra effort, the heart becomes thicker and stiffer, which leads to heart failure. Heart failure can cause extra fluid to build up in the body, and can also cause an irregular heartbeat. It does not mean that it is about to stop working, but it is a serious condition.
The investigation of ECG and blood pressure recordings and the study of heart contractility-relaxation allow researchers to detect and understand these cardiac structural abnormalities which enhance the heart failure risk.
Heart failure and sudden cardiac arrest
Sudden cardiac arrest results from an electrical disturbance that disrupts the heart pumping action. Heart failure does not always lead to sudden cardiac arrest but it increases the risk for it to occur.
Altered Heart Rate Variability (HRV) is a risk factor for sudden cardiac death and can be studied in vivo and in vitro.
For instance, a set of techniques including telemetry and isolated perfused heart systems can be considered (Comprehensive multilevel in vivo and in vitro analysis of heart rate fluctuations in mice by ECG telemetry and electrophysiology, Stefanie Fenske et al, VOL.11 NO.1, 2016). For such a system, ecgAUTO software can handle the whole data analysis:
“ecgAUTO is very powerful, and it provides many options for analysis. In addition, .txt files containing ECG or action potential recordings can be imported into ecgAUTO, which makes it is possible to analyze any ECG, patch-clamp data and microelectrode data.”
Understanding the close interaction between cardio and pulmonary outcomes
When the left ventricle is weakened, pressure increases in the lung vasculature allowing fluid to collect (pulmonary edema).
When the right ventricle is weakened, it is often a result of pulmonary hypertension, where the pulmonary arteries are narrowed or damaged. This makes it harder for blood to flow through the lungs and forces the right ventricle to work harder, eventually weakening the muscle.
Understanding this close interaction requires a two-step approach, investigating both cardio and pulmonary outcomes. This can be easily done with a single and non-invasive system such as emkaPACK4G telemetry (large animals) or ecgTUNNEL (rodents).
Pulmonary or hypertension can also be studied ex vivo, with a tissue bath system.
Implants for large animals
Implants for rats
Comprehensive multilevel in vivo and in vitro analysis of heart rate fluctuations in mice by ECG telemetry and electrophysiology
Stefanie Fenske et al, Nature protocols, 2015
Acetylcholine stimulated dilatation and stretch induced myogenic constriction in mesenteric artery of rats with chronic heart failure
Y. X u et al, European Journal of Heart Failure, 2007