Abstract
Chronic monitoring of heart rate, blood pressure, and flow in conscious free-roaming large animals can offer considerable opportunity to understand the progression of cardiovascular diseases and can test new diagnostics and therapeutics. The objective of this study was to demonstrate the feasibility of chronic, simultaneous measurement of several hemodynamic parameters (left ventricular pressure, systemic pressure, blood flow velocity, and heart rate) using a totally implantable multichannel telemetry system in swine heart failure models. Two solid-state blood pressure sensors were inserted in the left ventricle and the descending aorta for pressure measurements. Two Doppler probes were placed around the left anterior descending (LAD) and the brachiocephalic arteries for blood flow velocity measurements. Electrocardiographic (ECG) electrodes were attached to the surface of the left ventricle to monitor heart rate. The telemeter body was implanted in the right side of the abdomen under the skin for approximately 4 to 6 weeks. The animals were subjected to various heart failure models, including volume overload (A-V fistula, n = 3), pressure overload (aortic banding, n = 2) and dilated cardiomyopathy (pacing-induced tachycardia, n = 3). Longitudinal changes in hemodynamics were monitored during the progression of the disease. In the pacing-induced tachycardia animals, the systemic blood pressure progressively decreased within the first 2 weeks and returned to baseline levels thereafter. In the aortic banding animals, the pressure progressively increased during the development of the disease. The pressure in the A-V fistula animals only showed a small increase during the first week and remained stable thereafter. The results demonstrated the ability of this telemetry system of long-term, simultaneous monitoring of blood flow, pressure and heart rate in heart failure models, which may offer significant utility for understanding cardiovascular disease progression and treatment.
Highlights
Blood pressure, blood flow and heart rate are often altered under different cardiovascular conditions, such as heart failure
We previously developed an implantable radio-telemetry system with multichannel and long life battery that was tested in normal animals [3]
Telemetry has been extensively used in different animal models to understand the progression of cardiovascular diseases
Summary
Blood flow and heart rate are often altered under different cardiovascular conditions, such as heart failure. The monitoring of these parameters is seminal in the study of cardiovascular physiology, pathogenesis, pharmacology and treatment modalities. It is desirable to obtain these vitals in conscious animals, which is often achieved by restraining the animals and taking the measurements through indwelling exteriorized catheters and blood pressure cuffs. The restrain of the animals, introduces significant stress, and the measurements may be confounded by multiple factors such as increased plasma catecholamine and cortisol [18,21]. The presence of the indwelling catheters in chronic animal models increases the risk of thrombosis and infection
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
