Novel 2-arylbenzimidazoles and azabenzimidazoles were synthesized, and their inotropic action was evaluated. Changes in left ventricular pressure, dPldt ma, were measured as an index of cardiac contractility. The structural features that impart optimal inotropic activity are presented. The most potent compounds were evaluated orally in conscious dogs with implanted Konigsberg pressure transducers. To investigate the mechanism of action, the ...