[Arrhythmogenic effect of acoustic cavitation in isolated rat heart perfused with physiological solution].
In experiments on isolated rat hearts the effects of focused continuous and impulse ultrasound (543 Hz, with intensity up to 7.8 W/cm2 at a focal region) on a pressure developed by left ventricle and electrograms were studied. In all experiments ultrasound induced extra-excitations of the heart, which appeared when intensity was 1.35 +/- 0.21 W/cm2 (n = 9). Simultaneously with the extra-excitations the cavitation bursts were recorded at intensity of 1.52 +/- 0.18 W/cm2 (n = 6). Acoustic cavitation (after 30 sec of exposure) resulted in a significant decrease of the developed pressure (from 100.8 +/- 3.8 mm Hg to 95.1 +/- 4.3 mm Hg, p 0.001), measured in 2 min after the end of the exposure. In the absence of cavitation the ultrasound was found to have no effects on cardiac performance. Electrograms recorded during acoustic pacing show that a pattern of the heart excitation changed from stimulus to stimulus.
Zakharov
S I
SI
Bogdanov
K Iu
KIu
Rozenshtraukh
L V
LV
D000161:Acoustic Stimulation; D000818:Animals; D001145:Arrhythmias, Cardiac / Q000209:etiology*; D004558:Electric Stimulation; D004594:Electrophysiology; D006321:Heart / Q000502:physiology*; D066298:In Vitro Techniques; D010477:Perfusion; D051381:Rats; D012965:Sodium Chloride; D014465:Ultrasonics
D012965:Sodium Chloride
Aritmogennoe deĭstvie akusticheskoĭ kavitatsii na izolirovannoe serdtse krysy, perfusiruemoe fiziologicheskim rastvorom.