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Acta Physiologica 2012; Volume 206, Supplement 693
Joint FEPS and Spanish Physiological Society Scientific Congress 2012
9/8/2012-9/11/2012
Santiago de Compostela, Spain
EFFECT OF CHRONIC PHYSICAL EXERCISE ON THE ELECTROPHYSIOLOGICAL INHOMOGENEITY OF VENTRICULAR MYOCARDIUM. EXPERIMENTAL STUDY.
Abstract number: P196
Parra1 G, Barber1 J, Such-Miquel2 L, Diaz2 B, Salvador1 R, Pelechano1 F, Trapero3 I, Alberola1 A, Such1 L, Chorro4 F
1Physiology, University of Valencia,
2Physiotherapy, University of Valencia,
3Infirmary, University of Valencia,
4Medicine, University of Valencia
Objectives:
It has been reported that physical training could protect against cardiac sudden death and it has been proposed as an antiarrhythmic intervention. However, the exact mechanisms involved in this protection remain unclear. Previous research performed by us and other research groups suggest a decrease in myocardial electrophysiological heterogeneity by training, which is closely related to the occurrence of re-entrant arrhythmias life threatening. We propose in this paper demonstrate the hypothesis that chronic exercise reduces the physiological heterogeneity of myocardium through the analysis the spatial dispersion of the spectral concentration of induced ventricular fibrillation (VF) in isolated rabbit heart normally perfused and oxygenated.
Materials:
15 rabbits were submitted to a treadmill running program for 6 weeks (5 days/wk) and 13 rabbits were housed during the same period. After training or housing, the rabbits were anaesthetized, euthanized and the hearts excised, isolated and connected to a Langendorff system. A pacing electrode and a plaque with 256 recording electrodes were positioned on the left ventricle for recording. VF was triggered, pacing at increasing frequencies and maintained during five minutes. Dominant frequency of VF was determined by a spectral analysis. The mean spectral concentration (MSC) and its coefficient of variation (CV): standard deviation/MSC, as parameter of heterogeneity, were determined in each experiment. Determinations were analysed five minutes after the onset of VF in the two experimental groups. A t-Student test was used to compare the groups. Was considered significant when p<0.05.
Results:
The MSC in the trained was similar than in the control group (30.68±5.60; n=15 vs 31.19±7.11; n=12). CV in the trained group was less (22.56±3.05; n=15) than control group (26.11±4.01; n=12).
Conclusions:
Chronic physical exercise seems to decrease the physiological inhomogeneities of ventricular myocardium.
Supported by MEC (DEP2006-56208-C03-01 and SAF2007-62412).
To cite this abstract, please use the following information:
Acta Physiologica 2012; Volume 206, Supplement 693 :P196