List the myocardial pacemaker cell types in order of fastest to slowest. Circle (or indicate) the cells that set the sinus rhythm.

Order these steps of the myocardial pacemaker cell action potential: repolarization phase, slow initial depolarization phase, full depolarization phase, minimum potential phase. Circle (or indicate) the phase that triggers the action potential.

Myocardial contractile cells have lots of _________________ (for energy), __________________ which contain desmosomes and gap junctions, as well as ____________________ (unit of contraction).

Order these steps of the myocardial contractile cell action potential: repolarization phase, depolarization phase, initial repolarization phase, plateau phase. Circle (or indicate) the phase when BOTH the Ca2+ channels and K+ channels are open.

Name three consequences of the plateau phase in cardiac contractile cells.

True or false: sustained contraction of the heart (tetany) means that it is able to do its job of pumping blood SUPER well.

Identify the following conduction system structures: AV node, AV bundle, bundle branches, Purkinje fibers, SA node, intermodal pathway.

What is the ECG measuring? What kind of information can an ECG provide to a health care Practitioner?

Using the drawing of a normal ECG trace, identify the P wave, QRS complex, T wave, P-R interval, S-T segment, Q-T interval. The electrical events (i.e. depolarization) in the heart precede (come before) the physical event (i.e. systole). On the ECG trace below, also identify the following physical events: atrial systole, ventricular systole, ventricular diastole, atrial diastole.

Define the following terms. Feel free to use Google! Be sure to include the ranges of heart rates included in each definition, where applicable: bradycardia, tachycardia, fibrillation, arrhythmia.