Echo Registry Review Q&A 2023

Produced when a signal from the SA node spreads through the atria on a ECG - Answer- P-Wave Detects electrical current in the heart - Answer- Electrocardiogram Generated by ventricular repolarization - Answer- T-Wave produced when signal from AV node spreads through ventricular myocardium and depolarizes muscle - Answer- QRS complex The heart beats due to this - Answer- autorhythmicity Charge shifts from negative to positive - Answer- Depolarization Nerve like process that spreads action potential through ventricular myocardium - Answer- Purkinjefibers Primary Pacemaker cell of the heart - Answer- SA Node Short branched cell found in the heart - Answer- Cardiocyte Stores and pumps calcium ions - Answer- Sarcoplasmic reticulum Plateau phase of the cardiac action potential - Answer- Phase 2 Begins halfway through Phase 0 until part way thru phase 3 - Answer- (Absolute ) Refractory period allow action potential to spread through cells - Answer- Gap junctions Fast Na+ channels open in this phase - Answer- Phase 0 Phase in which cell is not stimulated ( resting membrane potential ) - Answer- Phase 4 Autoarythmic cells are also known as - Answer- pacemaker cells Phase 4 in autoarythmic cells differ from phase 4 in cardiocytes in which way ? - Answer- phase 4 in autoarythmic cells has no stable resting membrane where as in cardiocytes, phase 4 has a resting membrane potential. Sequences of changes within the cell which causes it to depolarize and repolarize. - Answer- Action potential A Car