title: Ranolazine as an adjunct to cardioplegia: a potential new therapeutic application.
abstract: The purpose of this study was to examine the therapeutic potential of ranolazine, a novel antianginal drug, as an adjunctive therapy to hyperkalemic cardioplegia. Rat hearts were Langendorff-perfused and exposed to 40 minutes of ischemia and 30 minutes of reperfusion without (control) or with cardioplegia or cardioplegia with 50 micromol/L ranolazine. During ischemia, cardioplegia prolonged time to contracture, defined as the time to reach an intraventricular pressure of 20 mm Hg, from 12 +/- 1 minute (control) to 25 +/- 2 minutes (P < .05). Ranolazine supplement further lengthened the time to contracture to 34 +/- 2 minutes (P < .05). Ischemia/reperfusion caused a dramatic elevation in left ventricular end diastolic pressure (LVEDP) during reperfusion. Cardioplegia lessened the LVEDP elevation measured at 30 minutes of reperfusion from 76 +/- 3 mm Hg (control) to 32 +/- 3 mm Hg (P < .05). The increase in LVEDP was reduced even further to 17 +/- 2 mm Hg in hearts receiving cardioplegia plus ranolazine (P < .05). These results suggest that addition of ranolazine during hyperkalemic ischemic cardioplegic arrest is beneficial and provides further protection against contracture.
authors.affiliation: Heart Institute, Good Samaritan Hospital, Los Angeles, California 90017, USA.
authors.forename: Hyosook
authors.initials: H
authors.lastname: Hwang
authors.forename: Joseph M
authors.initials: JM
authors.lastname: Arcidi
authors.forename: Sharon L
authors.initials: SL
authors.lastname: Hale
authors.forename: Boris Z
authors.initials: BZ
authors.lastname: Simkhovich
authors.forename: Luiz
authors.initials: L
authors.lastname: Belardinelli
authors.forename: Arvinder K
authors.initials: AK
authors.lastname: Dhalla
authors.forename: John C
authors.initials: JC
authors.lastname: Shryock
authors.forename: Robert A
authors.initials: RA
authors.lastname: Kloner