Cardiac action potential to fail, then the heart could continue to beat, albeit at a lower rate (AVN= 40-60 beats per minute, purkinje fibres = 20-40 beats per minute). These pacemakers will keep a patient alive until the emergency team arrives. An example of premature ventricular contraction, is the classic athletic heart syndrome. Sustained training of athletes causes a cardiac adaptation where the resting SAN rate is lower (sometimes around 40 beats per minute). This can lead to atrioventricular block, where the signal from the SAN is impaired in its path to the ventricles. This leads to uncoordinated contractions between the atria and
Cardiac neural crest cells secondary heart field cells into the cardiac outflow tract. FGF8 mouse mutants have a range of cardiac defects including underdeveloped arch arteries and transposition of the great arteries. GATA transcription factors, which are complex molecules that bind to the DNA sequence "GATA", play a critical role in cell lineage differentiation restriction during cardiac development. The primary function of GATA6 in cardiovascular development is to regulate the morphogenetic patterning of the outflow tract and aortic arch. When GATA6 is inactivated in CNCCs, various cardiovascular defects such as persistent truncus arteriorus and interrupted aortic arch may occur. This phenotype (anomaly) was also