TY - JOUR
T1 - In vivo murine left ventricular pressure-volume relations by miniaturized conductance micromanometry
AU - Georgakopoulos, Dimitrios
AU - Mitzner, Wayne A.
AU - Chen, Chen Huan
AU - Byrne, Barry J.
AU - Millar, Huntly D.
AU - Hare, Joshua M.
AU - Kass, David A.
PY - 1998/4
Y1 - 1998/4
N2 - The mouse is the species of choice for creating genetically engineered models of human disease. To study detailed systolic and diastolic left ventricular (LV) chamber mechanics in mice in vivo, we developed a miniaturized conductance-manometer system. α-Chloralose-urethan-anesthetized animals were instrumented with a two-electrode pressure-volume catheter advanced via the LV apex to the aortic root. Custom electronics provided time-varying conductances related to cavity volume. Baseline hemodynamics were similar to values in conscious animals: 634 ± 14 beats/min, 112 ± 4 mmHg, 5.3 ± 0.8 mmHg, and 11,777 ± 732 mmHg/s for heart rate, end-systolic and end-diastolic pressures, and maximum first derivative of ventricular pressure with respect to time (dP/dt(max)), respectively. Catheter stroke volume during preload reduction by inferior vena caval occlusion correlated with that by ultrasound aortic flow probe (r2 = 0.98). This maneuver yielded end-systolic elastances of 79 ± 21 mmHg/μl, preload-recruitable stroke work of 82 ± 5.6 mmHg, and slope of dP/dt(max)-end-diastolic volume relation of 699 ± 100 mmHg·s-1·μl-1, and these relations varied predictably with acute inotropic interventions. The control normalized time-varying elastance curve was similar to human data, further supporting comparable chamber mechanics between species. This novel approach should greatly help assess cardiovascular function in the blood-perfused murine heart.
AB - The mouse is the species of choice for creating genetically engineered models of human disease. To study detailed systolic and diastolic left ventricular (LV) chamber mechanics in mice in vivo, we developed a miniaturized conductance-manometer system. α-Chloralose-urethan-anesthetized animals were instrumented with a two-electrode pressure-volume catheter advanced via the LV apex to the aortic root. Custom electronics provided time-varying conductances related to cavity volume. Baseline hemodynamics were similar to values in conscious animals: 634 ± 14 beats/min, 112 ± 4 mmHg, 5.3 ± 0.8 mmHg, and 11,777 ± 732 mmHg/s for heart rate, end-systolic and end-diastolic pressures, and maximum first derivative of ventricular pressure with respect to time (dP/dt(max)), respectively. Catheter stroke volume during preload reduction by inferior vena caval occlusion correlated with that by ultrasound aortic flow probe (r2 = 0.98). This maneuver yielded end-systolic elastances of 79 ± 21 mmHg/μl, preload-recruitable stroke work of 82 ± 5.6 mmHg, and slope of dP/dt(max)-end-diastolic volume relation of 699 ± 100 mmHg·s-1·μl-1, and these relations varied predictably with acute inotropic interventions. The control normalized time-varying elastance curve was similar to human data, further supporting comparable chamber mechanics between species. This novel approach should greatly help assess cardiovascular function in the blood-perfused murine heart.
KW - Conductance volumetry
KW - Hemodynamics
KW - Mouse
KW - Ventricular function
UR - http://www.scopus.com/inward/record.url?scp=33750871446&partnerID=8YFLogxK
U2 - 10.1152/ajpheart.1998.274.4.h1416
DO - 10.1152/ajpheart.1998.274.4.h1416
M3 - Article
C2 - 9575947
AN - SCOPUS:33750871446
SN - 0363-6135
VL - 274
SP - H1416-H1422
JO - American Journal of Physiology - Heart and Circulatory Physiology
JF - American Journal of Physiology - Heart and Circulatory Physiology
IS - 4 43-4
ER -