title: Longitudinal hemodynamic measurements in swine heart failure using a fully implantable telemetry system.
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.
authors.affiliation: Department of Biomedical Engineering, Indiana University Purdue University Indianapolis, Indianapolis, Indiana, United States of America.
authors.forename: Jenny S
authors.initials: JS
authors.lastname: Choy
authors.affiliation: Department of Biomedical Engineering, Indiana University Purdue University Indianapolis, Indianapolis, Indiana, United States of America.
authors.forename: Zhen-Du
authors.initials: ZD
authors.lastname: Zhang
authors.affiliation: Transonic EndoGear Inc., Davis, California, United States of America.
authors.forename: Koullis
authors.initials: K
authors.lastname: Pitsillides
authors.affiliation: Transonic Systems Inc., Ithaca, New York, United States of America.
authors.forename: Margo
authors.initials: M
authors.lastname: Sosa
authors.affiliation: Department of Biomedical Engineering, Indiana University Purdue University Indianapolis, Indianapolis, Indiana, United States of America; Department of Surgery, Indiana University, Indianapolis, Indiana, United States of America; Department of Cellular and Integrative Physiology, Indiana University, Indianapolis, Indiana, United States of America.
authors.forename: Ghassan S
authors.initials: GS
authors.lastname: Kassab
mesh_terms: D000818:Animals; D001783:Blood Flow Velocity; D001794:Blood Pressure; D005260:Female; D006333:Heart Failure / Q000503:physiopathology*; D006339:Heart Rate; D006439:Hemodynamics; D008297:Male; D008991:Monitoring, Physiologic; D013552:Swine; D013686:Telemetry