LP #105 Dysfunction As A Fxn Of Lost Structural Or Functional Integrity Flashcards
- Checks heart fxn
- measures cardiac cycle rhythm (electrical activity)
- Predictable & repeated pattern of waves
(ECG) Electrocardiography tracings
Reading ECG tracings (P wave)
- 1st wave, small amplitude
- depolarization wave from SA node to atria
Reading ECG tracings (QRS complex)
- small dip (Q) to large peak (R) to larger dip (S)
- d/t ventricular depolarization & precedes ventricular contraction
Reading ECG tracings (T wave)
- 3rd wave, small amplitude
- ventricular repolarization
- abn rate of heart contractions
- d/t problems w/intrinsic conduction
- leads to uncoordinated myocardial contractions
- affects circulation
- may occur in healthy or diseased hearts
- may cause tachycardia or bradycardia
Cardiac arrhythmia
- Excessive rapid heart rate
- decrease blood filing heart (diastole)= decrease blood pumped out (systole)
- requires increase O2 & nutrients but needs not met d/t decrease blood filling heart in diastole
- leads to decrease coronary circulation (ischemia)
Tachycardia
- excessive flow heart rate
- causes impaired BF & ischemia to vital organs
Bradycardia
- rapid irregular contractions of the myocardium= poor blood pumping
- life threatening (defibrillation)
Fibrillation
Disruptions in AP initiation or signal conduction=
Cardiac dysfxn
- excitable focus outside a faulty SA node
- assumes control of HR
Ectopic pacemakers
- occurs w/damaged nn
- impulses are unable to move across damaged section d/t scar tissue
Heart conduction block
-medical replacement of defective intrinsic pacemakers
Artificial pacemakers
Causes of cardiac arrhythmia & conduction block
- congenital defects
- degenerative changes
- ischemia & myocardial infractions
- fluid & electrolyte imbalances
- P changes in hearts chambers open/closes vavles (depends on structural integrity)
- structural integrity is lost d/t scar tissue build up on valves & chordae tendinae
Valvular defects
Causes of valvular defects
- congenital
- ischemia
- inflammation & fibrosis