R 80123 is the Z-isomer of R 79595, is also a highly selective phosphodiesterase inhibitor. The fuction is similar to R 80122 .In vivo: The administration of Revizinone improved the haemodynamic profile with an increase in cardiac output, a decrease in systemic vascular resistance and a stable heart rate and mean arterial blood pressure. [1] With regard to reconstitution of contractility and cardiac function Revizinone (E-isomer) is 10 fold more potent than R 79595 and nearly 100 fold more potent than R 80123 (Z-isomer). [2] Revizinone significantly increases global LV function and systolic wall thickening in ischemic areas at doses greater than or equal to 0.16 mg/kg i.v. [3]

[1]. Vandeplassche GM et al. Comparative effects of R 80122, enoximone, and milrinone on left ventricular phosphodiesterase isoenzymes in vitro and on contractility of normal and stunned myocardium in vivo in dogs. J Cardiovasc Pharmacol. 1992 May;19(5):714-22.https://www.ncbi.nlm.nih.gov/pubmed/ 1381769 [2]. Schneider J et al. Cardiac effects of R 79595 and its isomers (R 80122 and R 80123) in an acute heart failure model. A new class of cardiotonic agents with highly selective phosphodiesterase III inhibitory properties. Naunyn Schmiedebergs Arch Pharmacol. 1992 Nov;346(5):563-72. [3]. Vandeplassche GM et al. Comparative effects of R 80122, enoximone, and milrinone on left ventricular phosphodiesterase isoenzymes in vitro and on contractility of normal and stunned myocardium in vivo in dogs. J Cardiovasc Pharmacol. 1992 May;19(5):714-22.