EKGs

What are the normal heart rate values?

60-100 beats per minute.

Describe left axis deviation on an EKG.

More negative deflection (down) in inferior leads (II, III, aVF) and positive deflection (up) in left lateral leads (I, aVL).

What does right axis deviation indicate in EKG leads?

Right axis deviation shows more positive deflection (up) in inferior leads (II, III, aVF) and negative deflection (down) in left lateral leads (I, aVL).

What is a common cause of A-Fib?

Pulmonary vein irritation, leading to disorganized electrical signals and an irregular heart rate.

What is indicated by tall R waves in the left lateral leads?

Left ventricular hypertrophy and increased electrical activity.

What does symmetric T-wave depression indicate?

Cases of ischemia or left ventricular strain.

What does asymmetric T-wave depression signify?

Due to repolarization abnormalities, often associated with myocardial infarction or left bundle branch block.

What QTc interval value is a red flag for Torsades de Pointes (TdP)?

QTc > 500 ms

What arrhythmia can PVCs and bradycardia lead to?

Torsades de Pointes (TdP).

What precautions must be taken during synchronized cardioversion for A-Fib?

Ensure the defibrillator is set correctly and the shock timing coincides with the R wave to avoid causing TdP.

What is the definition of first degree heart block in terms of the P-R interval?

The P-R interval is ≥ 260 ms.

What does a downward P wave in V1 indicate?

Left atrial enlargement.

What does an upward P wave in V1 suggest?

Right atrial enlargement.

What might a wide QRS complex suggest on an EKG?

Bundle branch block.

What does a QS complex with a Q wave signify?

Old myocardial infarction.

What condition is suggested by diffuse ST elevation without ST segment depression?

Pericarditis.

What could cause T wave inversion in the lateral leads?

Ischemia or prior myocardial infarction.

Is an upright T wave normal?

Upright T waves usually indicate normal myocardial repolarization.

What does a prolonged QT interval indicate?

A risk for torsades de pointes.

What does a shortened QT interval suggest?

Hypercalcemia or digoxin toxicity.

What do U waves suggest on an EKG?

Hypokalemia or other electrolyte imbalances.

What should be included in a thorough evaluation of an EKG?

Careful consideration of T wave morphology, QT interval duration, and the presence of U waves.