ECG Rhythm Study Guide PDF

ECG Rhythm Study Guide Normal Sinus Rhythm Looking at the ECG you'll see that:  Rhythm ‐ Regular  Rate ‐ (60‐100 bpm)  QRS Duration ‐ Normal  P Wave ‐ Visible before each QRS complex  P‐R Interval ‐ Normal (5 small squares) 2nd Degree Block Type 1 (Wenckebach) Another c...

ECG Rhythm Study Guide Normal Sinus Rhythm Looking at the ECG you'll see that:  Rhythm ‐ Regular  Rate ‐ (60‐100 bpm)  QRS Duration ‐ Normal  P Wave ‐ Visible before each QRS complex  P‐R Interval ‐ Normal (5 small squares) 2nd Degree Block Type 1 (Wenckebach) Another condition whereby a conduction block of some, but not all atrial beats getting through to the ventricles. There is progressive lengthening of the PR interval and then failure of conduction of an atrial beat, this is seen by a dropped QRS complex. Looking at the ECG you'll see that:  Rhythm ‐ Regularly irregular  Rate ‐ Normal or Slow  QRS Duration ‐ Normal  P Wave ‐ Ratio 1:1 for 2,3 or 4 cycles then 1:0.  P Wave rate ‐ Normal but faster than QRS rate  P‐R Interval ‐ Progressive lengthening of P‐R interval until a QRS complex is dropped www.lifesavercpr.net (209) 499‐2249 [email protected] 2nd Degree Block Type 2 When electrical excitation sometimes fails to pass through the A‐V node or bundle of His, this intermittent occurrence is said to be called second degree heart block. Electrical conduction usually has a constant P‐R interval, in the case of type 2 block atrial contractions are not regularly followed by ventricular contraction Looking at the ECG you'll see that:  Rhythm ‐ Regular  Rate ‐ Normal or Slow  QRS Duration ‐ Prolonged  P Wave ‐ Ratio 2:1, 3:1  P Wave rate ‐ Normal but faster than QRS rate  P‐R Interval ‐ Normal or prolonged but constant 3rd Degree Block 3rd degree block or complete heart block occurs when atrial contractions are 'normal' but no electrical conduction is conveyed to the ventricles. The ventricles then generate their own signal through an 'escape mechanism' from a focus somewhere within the ventricle. The ventricular escape beats are usually 'slow' Looking at the ECG you'll see that:  Rhythm ‐ Regular  Rate ‐ Slow  QRS Duration ‐ Prolonged  P Wave ‐ Unrelated  P Wave rate ‐ Normal but faster than QRS rate  P‐R Interval ‐ Variation  Complete AV block. No atrial impulses pass through the atrioventricular node and the ventricles generate their own rhythm www.lifesavercpr.net (209) 499‐2249 [email protected] Bundle Branch Block Abnormal conduction through the bundle branches will cause a depolarization delay through the ventricular muscle, this delay shows as a widening of the QRS complex. Right Bundle Branch Block (RBBB) indicates problems in the right side of the heart. Whereas Left Bundle Branch Block (LBBB) is an indication of heart disease. If LBBB is present then further interpretation of the ECG cannot be carried out. Looking at the ECG you'll see that:  Rhythm ‐ Regular  Rate ‐ Normal  QRS Duration ‐ Prolonged  P Wave ‐ Ratio 1:1  P Wave rate ‐ Normal and same as QRS rate  P‐R Interval ‐ Normal Premature Ventricular Complexes Due to a part of the heart depolarizing earlier than it should Looking at the ECG you'll see that:  Rhythm ‐ Regular  Rate ‐ Normal  QRS Duration ‐ Normal  P Wave ‐ Ratio 1:1  P Wave rate ‐ Normal and same as QRS rate  P‐R Interval ‐ Normal www.lifesavercpr.net (209) 499‐2249 [email protected]   Also you'll see 2 odd waveforms, these are the ventricles depolarizing prematurely in response to a signal within the ventricles.(Above ‐ unifocal PVC's as they look alike if they differed in appearance they would be called multifocal PVC's, as below) Junctional Rhythms Looking at the ECG you'll see that:  Rhythm ‐ Regular  Rate ‐ 40‐60 Beats per minute  QRS Duration ‐ Normal  P Wave ‐ Ratio 1:1 if visible. Inverted in lead II  P Wave rate ‐ Same as QRS rate  P‐R Interval ‐ Variable Below ‐ Accelerated Junctional Rhythm www.lifesavercpr.net (209) 499‐2249 [email protected] Ventricular Tachycardia (VT) Abnormal Looking at the ECG you'll see that:  Rhythm ‐ Regular  Rate ‐ 180‐190 Beats per minute  QRS Duration ‐ Prolonged  P Wave ‐ Not seen  Results from abnormal tissues in the ventricles generating a rapid and irregular heart rhythm. Poor cardiac output is usually associated with this rhythm thus causing the pt to go into cardiac arrest. Shock this rhythm if the patient is unconscious and without a pulse Ventricular Fibrillation (VF) Abnormal Disorganized electrical signals cause the ventricles to quiver instead of contract in a rhythmic fashion. A patient will be unconscious as blood is not pumped to the brain. Immediate treatment by defibrillation is indicated. This condition may occur during or after a myocardial infarct. Looking at the ECG you'll see that:  Rhythm ‐ Irregular  Rate ‐ 300+, disorganized  QRS Duration ‐ Not recognizable  P Wave ‐ Not seen  This patient needs to be defibrillated!! QUICKLY www.lifesavercpr.net (209) 499‐2249 [email protected]  Asystole ‐ Abnormal Looking at the ECG you'll see that:  Rhythm ‐ Flat  Rate ‐ 0 Beats per minute  QRS Duration ‐ None  P Wave ‐ None  Carry out CPR!! Myocardial Infarct (MI) Looking at the ECG you'll see that:  Rhythm ‐ Regular www.lifesavercpr.net (209) 499‐2249 [email protected]