The evaluation of drug-induced changes in left ventricular function in pentobarbital-anesthetized dogs.

Introduction: The goal of this study was to determine whether assessment of myocardial contractility and hemodynamics in an anesthetized dog model, could consistently detect drug-induced changes in the inotropic state of the heart using drugs known to have clinically relevant positive and negative effects on myocardial contractility.

Methods: Derived parameters included: diastolic, systolic and mean arterial BP, peak systolic LVP, HR, end-diastolic LVP, and LVdP/dt as the primary contractility index.

Results: These results demonstrate that statistically significant increases (amrinone and pimobendan) and decreases (atenolol and itraconazole) in left ventricular dP/dt were observed at clinically relevant exposures.

Discussion: The analysis from the current study supports the strategic use of the anesthetized dog model early in the drug Discovery process for a comprehensive cardiovascular evaluation that can include left ventricular dP/dt with good translation to human.