Submitted on March 19, 2007
Accepted on July 6, 2007
The effects of an aging vascular model on healthy and diseased hearts.
David Jegger1*, R. Fernandes da Silva, Isabelle Lartaud, Xavier Jeanrenaud, Mohammad Nasratullah, Ludwig K. von Segesser, Jeffrey Atkinson, Patrick Segers2, Hendrik Tevaearai, and Nikos Stergiopulos3
1 LHCT, EPFL, Lausanne, Switzerland
2 CV Mechanics and Biofluid Dynamics, University of Ghent, Institute Biomedical Tech (IBiTech), Ghent, B-9000, Belgium
3 Institute for Biomedical Engineering, EPFL, Lausanne, Switzerland
* To whom correspondence should be addressed. E-mail: david.jegger{at}epfl.ch.
The vitamin D3 and nicotine (VDN) model is one of isolated systolic hypertension (ISH) due to arterial calcification raising arterial stiffness and vascular impedance similar to an aged and stiffened arterial tree. We therefore analyzed the impact of this aging model on normal and diseased hearts by way of myocardial infarction (MI).
Wistar rats were treated with VDN (VDN, n=9), subjected to MI by coronary ligation (MI, n=10) or to a combination of both MI and VDN treatment (VDN/MI, n=14). A sham treated group served as control (CTRL, n=10). Trans-thoracic echocardiography was performed every 2 weeks whereas invasive indices were obtained at week 8 before sacrifice. Calcium, collagen and protein contents were measured in the heart and the aorta.
Systolic blood pressure, pulse pressure, thoracic aortic calcium and end-systolic elastance as indix of myocardial contractility were the greatest in the aging model compared to MI and CTRL (pVDN of the 2 way ANOVA < 0.05). Left ventricular wall stress and BNP (pVDNxMI =NS) were the greatest while ejection fraction, stroke volume and cardiac output were the lowest in the combined group versus all other groups (pVDNxMI < 0.05).
The combination of ISH due to this aging model and MI demonstrates significant alterations in cardiac function. This model mimics several clinical phenomena of cardiovascular aging and may thus serve to further study novel therapies.
