Effect of cooling on rhythmo-inotropic relations in pathologically altered myocardium
Vornovitskiĭ, E.G.; Ignat'eva, V.B.; Kaĭdash, A.N.; Arapov, A.D.; Mogilevskiĭ, E.B.
Biulleten' Eksperimental'noi Biologii i Meditsiny 92(7): 10-14
1981
ISSN/ISBN: 0365-9615 PMID: 7295934 Document Number: 174196
Fragments of the right atrium auricle from patients with congenital and acquired heart diseases were used to study the effect of the Tyrode solution temperature over the 60-minute cessation of electrical stimulation of the preparations on the recovery of the amplitude of rhythmic contractions after the pause. The lack of stimulation within 34 to 24 degrees C does not lower the contraction amplitude after warming of the preparations and renewal of rhythmic stimulation. The hypothermal pause at a temperature of 10-14 degrees C leads to the development of contractures and suppresses the myocardial contractility. The positive inotropic action of dopamin (1.10(-6) g/ml), isadrin (1.10(-7) g/ml) and strophanthine (1.10(-6) g/ml) on the myocardium in patients with acquired heart diseases is remarkably diminished after the hypothermal pause.