PNB 2265 Lecture Notes - Lecture 9: Long Qt Syndrome, Qrs Complex, Atrioventricular Node

• School: UConn
• Department: Physiology and Neurobiology
• Course: PNB 2265
• Professor: Kristen Kimball

Document Summary

Clinical uses of ekg- sum of all the electrical activity inside the heart. Qrs ventricular depolarization and atrial repolarization: bundle of his, bundle branches, purkinje fibers, ventricular contractile cells. All cells in conductive system have pacemaker potential. May have less frequent qrs as different cells are now setting the pace: complete heart block (p waves and qrs complexes not coordinated) Long qt syndrome: slow recovery contraction, may lead to vfib, how long does it take electrical signal to go entirely through ventricles, t wave is very stretched out. Takes ventricles longer to repolarize: t wave is ventricular repolarization. Fi(cid:271)rillation: not ta(cid:272)hy(cid:272)ardia (cid:894)(cid:449)hat"s different?: uncoordinated contraction of atria and ventricles. Nothing wrong with av node, when you get pocket of atria depolarization, signal is sent down to ventricles, see qrs complex. Not evenly spaced, still uncoordinated ventricular depolarization. Atria contraction is not essential for filling ventricles, they passively fill about 70% Afib is treatable with medicines: heart cannot pump!