| Examine Heart Rhythm
1. Electrocardiogram (ECG): 12-lead ECG provides information about rate, rhythm, conduction, areas of ischemia, and infarct, hypertrophy, electrolyte imbalances, and systemic pathologies (COPD, cerebral T-waves, etc.).
2. Normal cardiac cycle (normal sinus rhythm) a. P wave: atrial depolarization. b. P-R interval: time required for impulse to travel from atria through conduction system to Purkinje fibers. c. QRS wave: ventricular depolarization. d. ST segment: beginning of ventricular repolarization. e. T wave: ventricular repolarization. f. QT interval: time for electrical systole.
3. Calculate heart rate: count number of intervals between QRS complexes in a 6-second strip and multiply by 10.
With irregular heart rates, use the longest strip possible (up to 1 minute) for a more accurate assessment of heart rate.
4. Assess rhythm: regular or irregula |