[Testing of the latissimus dorsi muscle stimulation regimens in the experimental model of thoracic aortomyoplasty].
OBJECTIVE
Among several alternative forms of treatment for congestive heart failure patients is the use of autologous muscle-powered cardiac assistance. Our investigation was aimed to study two different regimens of latissimus dorsi muscle electrostimulation in acute thoracic aortomyoplasty.


METHODS
Experiments were made in Kaunas University of Medicine and Wisconsin University, Milwaukee Heart institute. In two experimental groups (of 6 dogs each), aortomyoplasty was performed, using a new cardiomyostimulator LD-PACE II. The latissimus dorsi muscle was subject to one of the following stimulation regimens: continuous electrostimulation or work-rest electrostimulation (one minute work - one minute rest).


RESULTS
In group 1 (continuous electrostimulation regimen) thoracic aortic counterpulsation resulted in significantly improved hemodynamic parameters. However, after 60 minutes, hemodynamic values decreased to pre-assist levels. In group 2 (work-rest regimen) thoracic aortic counterpulsation resulted in significantly improved hemodynamic parameters during the first 20 minutes of testing but all values were worse than with the I group regimen. All values within the next 20 minutes were better than those obtained in I group, although not statistically significant. However, for a total of 60 minutes of counterpulsation, the differences between group 1 and group 2 did become statistically significant. In group 2 we continued counterpulsation for 100 minutes before values returned to baseline.


CONCLUSIONS
According to our study extraaortic counterpulsation using cardiomyostimulator LD-PACE II shows an improvement of hemodynamic parameters during assisted cardiac cycles; a new work-rest electrostimulation regimen is useful for saving latissimus dorsi muscle from damage of electrical stimulation.
Dumcius
Arimantas
A
Clinic of Heart Surgery, Kaunas University of Medicine Hospital, Eiveniu 2, 3007 Kaunas, Lithuania.
Bavarskis
Egidijus
E
Chekanov
Valeri
V
Vysockas
Vaidas
V
D032761:Animal Experimentation; D000818:Animals; D001013:Aorta, Thoracic / Q000601:surgery; D015908:Counterpulsation; D004285:Dogs; D004558:Electric Stimulation; D006353:Heart-Assist Devices; D006439:Hemodynamics / Q000502:physiology; D009119:Muscle Contraction; D018482:Muscle, Skeletal; D019739:Skeletal Muscle Ventricle; D013997:Time Factors