Electrocardiographic Parameters in the Gomeran Giant Lizard, Gallotia bravoana

Abstract

Electrocardiographic param eters w ere determ ined fo r one o f the m ost endangered species in the w orld, the G om eran giant lizard, Gallotia bravoana, w ith a population o f only ten captive individuals in the world. H eart rate, rhythm , am plitude o f P, R, S and T w aves, interval o f RR, PR, Q T and ST w aves, duration of P, QRS, T waves, description o f SV w ave (representing depolarisation o f the sinus venosus), m ean electrical a x is , a n d c o r r e la tio n w ith c lo a c a l te m p e r a tu r e a n d w e ig h t w e re d e te r m in e d in th is p o p u la tio n. Electrocardiographic tracings showed a positive QRS com plex, presence o f an SV w ave, and T w aves occasion ally negative. Positive correlation w as observed betw een electrical axis and w eight, P duration and am bient tem perature, and S am plitude and cardiac frequency. N egative correlation w as observed betw een electrical axis and cloacal tem perature, S-T duration and the am bient tem perature, R-R interval and the cloacal tem perature, and R-R interval and cardiac frequency. This is the first com plete description o f the electrocardiographic para m eters o f a giant lizard o f Lacertidae fam ily and genus Gallotia.

Standardisation of electrocardiographic examination in corn snakes (Pantherophis guttatus)

“…Yielded values demonstrated a left axis dominance (table 2), indicating that it is the left side of the common ventricle in corn snakes that makes up most of the myocardium. This axial dominance is similar to mammals, where the left ventricle is larger than the right, but is also similar to the few other reptile species for which MEA has been calculated, 26 39 40 indicating a common asymmetrical distribution of ventricular muscle mass in reptiles. The authors also found that MEA values produced in this study were highly conserved between individuals, suggesting a predictable direction of electrical flow through the myocardium and therefore a broadly uniform positioning of the heart within the coelom.…”

HNK‐1 in Morphological Study of Development of the Cardiac Conduction System in Selected Groups of Sauropsida

“…Although some ECG recordings were performed in Sauropsida in general (Kaplan and Schwartz, 1963;McDonald and Heath, 1971;Blanco, 1993;Heaton-Jones and King, 1994;Anderson et al, 1999;Espino et al, 2001;Martinez-Silvestre et al, 2003;Tan et al, 2013), the information available is restricted to a few species and there are almost no comparative studies among Squamate reptiles (Mullen, 1967;Bogan Jr., 2017) to fully understand the electrophysiological function of the heart in these terrestrial ectotherms. However, with respect to ECG methodology (Einthoven, 1903), there are also some limitations of this approach for poikilotherms and ectotherms.…”