Pressure-volume relation analysis of mouse ventricular function

Abstract

Cingolani OH, Kass DA. Pressure-volume relation analysis of mouse ventricular function. Am J Physiol Heart Circ Physiol 301: H2198 -H2206, 2011. First published September 16, 2011 doi:10.1152 doi:10. /ajpheart.00781.2011 years ago, the Sagawa laboratory spawned a renaissance in the use of instantaneous ventricular pressure-volume (P-V) relations to assess cardiac function. Since then, this analysis has taken hold as the most comprehensive way to quantify ventricular chamber function and energetics and cardiovascular interactions. First studied in large mammalian hearts and later in humans employing a catheter-based method, P-V analysis was translated to small rodents in the late 1990s by the Kass laboratory. Over the past decade, this approach has become a gold standard for comprehensive examination of in vivo cardiac function in mice, facilitating a new era of molecular cardiac physiology. The catheter-based method remains the most widely used approach in mice. In this brief review, we discuss this instrumentation, the theory behind its use, and how volume signals are calibrated and discuss elements of P-V analysis. The goal is to provide a convenient summary of earlier investigations and insights for users whose primary interests lie in genetic/molecular studies rather than in biomedical engineering. hemodynamics THIS ARTICLE is part of a collection on Assessing Cardiovascular Function in Mice: New Developments and Methods.Other articles appearing in this collection, as well as a full archive of all collections, can be found online at http:// ajpheart.physiology.org/.A comprehensive assessment of mouse cardiac hemodynamics in vivo can be essential to define the physiological significance of a given genetic or pharmacological modification. This is often measured using imaging tools (e.g., Doppler/ echocardiography or MRI) and left ventricular (LV) pressure data. However, a more detailed analysis may be desired, and this can be provided by ventricular pressure-volume (P-V) analysis. The P-V approach provides a comprehensive method to assess cardiac systolic and diastolic function in a manner less affected by arterial and venous loading while at the same time quantifying this load. Methods to derive P-V relations in mice, principally using a conductance catheter, were developed in the late 1990s in our laboratory and are now commercially available. The method and analysis require some appreciation of the signals and potential sources of error, as well as the underlying hemodynamics. The original work regarding P-V analysis dates back 40 years, when it was the focus of bioengineering and systems biologists (34). Its emergence in an era of molecular physiology in mice has made it all the more valuable to revisit the principles, assumptions, and limitations of these analytical approaches and the methodologies used to apply them. The contents of this review are not new; however, as the constellation of investigators using P-V analysis has dramatically changed from physiologist/engineers to molecular biologists, we t...

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