A novel anti-oxidative agent improves recovery of the heart after cardiac arrest.

Experiments were designed to determine whether adding a synthetic anti-oxidative agent H 290/51 (cis-7methyl-9-methoxy-5,5 a,6,10 b-tetrahydroindeno [2,1-b] indole), to a crystalloid cardioplegic solution was beneficial for myocardial recovery and coronary reactivity in isolated rat hearts after six hours cold arrest. Two groups of hearts were single-flush perfused using the Langendorff technique (10 ml at 4 degrees C) with either Plegisol (St. Thomas' Hospital Solution) (n = 6) or Plegisol with H 290/51 (n = 6) added to a final concentration of 1 mummol/L. The heart were then stored for six hours in the respective solution at 4 degrees C. A third group of hearts (n = 6) were single-flush with Plegisol and reperfusion was immediately started (the 'non-stored' group). Before and after the arrest phase the hearts were perfused at constant pressure with Krebs-Henseleit bicarbonate buffer. To evaluate coronary vascular function, endothelium-dependent vasodilatation was induced with 5-hydroxy-tryptamine (5-HT) and smooth-muscle relaxation with nitroglycerin (GTN). Myocardial contractility after 30 min reperfusion, measured as left-ventricular developed pressure (LVDP), was significantly improved in hearts in the Plegisol+H 290/51 group compared to hearts in the Plegisol group (LVDP 89 +/- 8.5% vs 57.2 +/- 10.7% of prearrest values; p < 0.05). LVDP in hearts receiving Plegisol+H 290/51 was comparable to non-stored hearts (88.2 +/- 1.3%). The vasodilatory response to GTN was significantly reduced in hearts perfused with plain Plegisol (p < 0.05) but not in hearts receiving Plegisol+H 290/51 or in the non-stored hearts.(ABSTRACT TRUNCATED AT 250 WORDS)