Evaluation of left ventricular function with continuous echocardiography concomitant with left ventricular pressure measurement in isoflurane anesthetized rats for safety pharmacology study

Mongrel dogs were used to quantify left ventricular function (LVF) in response to subendocardial electrical pacing from three left ventricular sites and one right ventricular site (RVO). Ventricular pacing sites were compared with atrial pacing at constant heart rates. LVF was significantly diminished with ventricular pacing when left ventricular pressure, maximal rate of left ventricular pressure rise, cardiac output, stroke work, and stroke power were considered. Left ventricular pacing values were significantly greater than RVO pacing values. Developed tension (DT) and maximal rate of tension development (max. dT/dt) were recorded from a strain-gauge arch; max. dT/dt decreased disproportionately greater than the decrease in DT with ventricular pacing. The reduced LVF was shown to be independent of myocardial contractility, heart rate, end-diastolic fiber length, previous tension, and resistance to shortening. Temporal dyssynergy of left ventricular contraction was shown to be an important determinant of LVF in addition to the above variables. Left ventricular synergism must be taken into account when assessing myocardial contractility in the intact left ventricle.

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Left ventricular pressure measurement in the telemetered dog

Toxicology Letters ◽

10.1016/j.toxlet.2010.03.847 ◽

2010 ◽

Vol 196 ◽

pp. S253

Author(s):

A. Simonnard ◽

A.M. Bétat ◽

S. Loriot ◽

R. Forster

Keyword(s):

Pressure Measurement ◽

Left Ventricular Pressure ◽

Left Ventricular ◽

Ventricular Pressure

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Evaluation of cardiac contractility by left ventricular pressure measurement in telemetered beagle dogs

Journal of Pharmacological and Toxicological Methods ◽

10.1016/j.vascn.2010.11.095 ◽

2010 ◽

Vol 62 (2) ◽

pp. e28

Author(s):

Thomas Schwitzer ◽

Anne Marie Btat ◽

Guillaume Froget ◽

Roy Forster

Keyword(s):

Pressure Measurement ◽

Cardiac Contractility ◽

Left Ventricular Pressure ◽

Left Ventricular ◽

Ventricular Pressure ◽

Beagle Dogs

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Effect of Contrast Media on Left Ventricular Function during Left Coronary Arteriography in Dogs

Acta Radiologica ◽

10.1177/028418518903000616 ◽

1989 ◽

Vol 30 (6) ◽

pp. 655-659 ◽

Cited By ~ 2

Author(s):

K. Hayakawa ◽

K. Yamashita

Keyword(s):

Contrast Media ◽

Left Ventricular Function ◽

Ventricular Function ◽

Ionic Composition ◽

Isotonic Saline ◽

Left Ventricular Pressure ◽

Coronary Arteriography ◽

Left Ventricular ◽

Post Injection ◽

Inotropic Effects

The effect of contrast media on the left ventricular function of the heart was assessed by left coronary administration of contrast media using canine models. Following insertion of the catheter into the left coronary artery, 0.5 ml/kg of a test solution was injected at a rate of 1 ml/s. The test solutions included isotonic saline, meglumine/sodium diatrizoate, iopamidol and ioxaglate. The mean systemic pressure, left ventricular end-systolic and end-diastolic pressures and the first derivative of left ventricular pressure were continuously measured until five min post-injection. Left ventricular function decreased immediately by 15 s post-injection and recovered quickly by one min. The inhibition of myocardial contractility was observed with diatrizoate and ioxaglate to the same degree. These changes were statistically more pronounced than those with iopamidol, which showed changes similar to those with saline in all parameters except for the positive inotropic effects. These observations suggest that not only hyperosmolality but also ionic composition and chemotoxicity are the factors responsible for the myocardial depression and that no single factor dominates in their effects.

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