EKG Tutorial Part 1 & 2 Flashcards
What is the Tx for sinus tachycardia?
Treat underlying cause
What is the pacemaker of the heart?
SA node
What effect does acute inferior MI have on the heart rate?
Bradycardia
What is the tx for sinus bradycardia if it is symptomatic?
Atropine
What is automaticity?
Cardiac cell depolarizes spontaneously during phase 4 of action potential which leads to generation of an impulse
What is seen in a absence of significant heart disease; associated with stress, alcohol, tobacco, coffee, COPD, and CAD?
Premature Atrial Contraction
What does a non-conducted premature atrial contraction look like on ecg?
No QRS following a premature P wave
What is the Tx of premature atrial contractions?
1) Stop the underlying cause
2) Beta blocker such as metoprolol
What is paroxysmal atrial tachycardia?
Sudden onset heart rate greater than 100
What is seen on ecg with paroxysmal atrial tachycardia with AV block?
What is the most likely cause?
1) Spiked P waves and a 2:1 ration of P:QRS
2) Digitalis toxicity
What is multifocal atrial tachycardia characterized by?
What intervals vary?
What is the rhythm?
What is the rate?
1) 3 or more different P waves
2) P-R interval varies
3) Irregular ventricular rhythm
4) HR > 100
Multifocal Atrial Tachycardia is associated with?
What is the axis in this situation?
1) Lung disease
2) Right axis
What should you avoid when treating multifocal atrial tachycardia due to the pulmonary problems?
Beta blockers
What is the Tx for multifocal atrial tachycardia?
Calcium channel blockers such as diltiazem and verapamil
What is the atrial rate for atrial fibrillation?
What does it look like on ecg?
What interval is irregular?
What is the ventricular rhythm described?
1) >350-600/min
2) Undulating baseline (not flat) and no P waves
3) RR interval
4) Irregularly irregular
What characteristic appearance does atrial flutter have?
What leads is it best seen in?
1) Saw tooth
2) Leads II, III, AVF, V
What does Paroxysmal junctional tachycardia look like on ecg?
P waves can be lost in QRS complex, inverted before QRS or after QRS
Paroxysmal supraventricular tachycardia includes?
Paroxysmal atrial tachycardia and paroxysmal junctional tachycardia
What does premature ventricular contractions look like on ecg?
1) Premature wide QRS
2) No preceding P wave
3) ST-T wave moves in opposite direction of QRS
When should you use metoprolol to treat premature ventricular contractions?
When should you use amiodarone, lidocaine, or procainamide?
1) Stable PVC but still symptomatic
2) Unstable PVC
Ventricular Tachycardia is defined by?
What is the ventricular rate?
What happens to the P wave?
How long does it last?
What type of beat is it associated with?
1) 3 or more consecutive wide QRS complexes
2) 120-200
3) Lost
4) Longer than 30 seconds
5) Fusion beats (Dressler)
What does Torsades de Pointes look like on ECG?
QRS swings from positive to negative direction
If Torsades de Pointes is inherited it is associated with?
Long QT
How is Torsades de Pointes treated?
MgSO4
What is characterized by disorganized depolarization and ineffective pumping of blood?
Ventricular fibrillation
A block that causes a disruption of atrial-to-ventricular electrical conduction is known as?
AV block
What indicates 1st degree AV block?
PR interval more than 0.2 seconds
What are some causes of 1st degree AV block?
1) Atherosclerosis
2) Hypertension
3) Diabetes
4) Fibrosis
What are the two types of 2nd degree AV block?
1) Mobitz I (Wenckebach)
2) Mobitz II
What indicates Mobitz I (Wenckebach) 2nd degree AV block?
What indicates Mobitz II?
1) Progressive PR interval prolongation prior to dropped QRS
2) PR interval uniform and dropped QRS
Mobitz I (Wenckebach) 2nd degree AV block can be seen with?
What can Mobitz II be seen with?
1) Inferior MI
2) Anterior MI
Which 2nd degree AV block has a worse prognosis?
Mobitz II
Where is the site of block for Mobitz II?
Lower than AV node such as Bundle of His
What indicates 3rd degree heart block aka complete heart block?
P waves that beat independently from QRS complexes
When is a 3rd degree block characterized as a junctional rhythm?
What does this result in?
1) Block is above AV node
2) Narrow QRS
When is a 3rd degree block characterized as a ventricular pacemaker?
What does this result in?
1) Block is below AV node
2) Wide QRS
What are common features of bundle branch block (BBB)?
1) Wide QRS complex
2) ST segment – T waves slope off in opposite direction to QRS
How do you differentiate between left and right BBB?
1) In LBBB the QRS complex is downwardly deflected in lead V1
2) In RBBB the QRS complex is upwardly deflected in lead V1
What are hemiblocks?
Term for blockage of one of two main division of left bundle branch
Which hemiblock is more common, left anterior hemiblock or left posterior hemiblock?
Left anterior hemiblock
What is the criteria for left anterior hemiblock?
1) Left axis deviation
2) Small Q in leads I and AVL
3) Small R in leads II, III and AVF
What is the criteria for left posterior hemiblock?
1) Right axis deviation
2) Small R in leads I and AVL
3) Small Q in leads II, III, AVF
What are some ways that cause atrial enlargement?
1) Increase in volume of blood in the chamber
2) Increase in resistance to blood flow out of chamber
What leads is atrial enlargement best seen in?
I, II, III, V1
Which atrium is activated first in atrial enlargment?
RA
What does right atrial enlargement look like on ecg?
Tall, pointed p wave
Right atrial enlargement is associated with what condition?
Pulmonary HTN
What does left atrial enlargement look like on ecg?
M shaped P wave called P-mitrale
What is right atrial enlargement caused by?
Mitral stenosis or regurgitation
What is the most common cause of left ventricular hypertrophy?
HTN
What does left ventricular hypertrophy look like on ecg?
1) Deep S waves and tall R waves in limb leads
2) Deep S waves in V1, V2, or V3
3) Tall R waves in V5, V6
What is the most common cause of right ventricular hypertrophy?
COPD
What does right ventricular hypertrophy look like on ecg?
1) Right axis
2) Tall R waves in V1
3) Deep S waves in V6
4) R/S ratio in V1 > 1
5) S/R ratio in V6 > 1
What effect does acidosis have on the heart?
Increased risk for Vfib
What does hypokalemia look like on ecg?
1) Prominent U waves
2) Long QT
3) Flat or inverted T wave
What is a common cause of hypokalemia?
Diuretics
What is a common cause of hyperkalemia?
Renal failure
What does hyperkalemia look like on ecg?
1) Peaked T wave
2) Wide QRS
3) Long PR interval
4) No P wave
What are common causes of hypercalcemia?
1) Hyperparathyroidism
2) Malignancy
What does hypercalcemia look like on ecg?
1) Short QT interval
2) Short ST segment
What does hypocalcemia look like on ecg?
1) Long QT interval
2) Long ST segment
What is hypothermia defined as?
What happens to HR?
What is the characteristic finding on ecg?
1) Less than 35◦ C (95◦ F)
2) Bradycardia
3) J wave or Osborne wave (notch after QRS complex)
What effect does a pulmonary embolus have on HR?
Tachycardia
What does a PE look like on ecg?
1) Large S wave in lead I
2) ST depression in II
3) Large Q wave in III
4) T wave inversion in V1-V4
5) RBBB
What does Wolff-Parkinson – White Syndrome look like on ecg?
1) Short PR interval
2) Slurred upstroke (delta wave) of QRS complex
What conduction pathway is involved with Wolff-Parkinson – White Syndrome?
Bundle of Kent
What does acute pericarditis look like on ecg?
1) Concave ST segment elevation in leads I, II, aVL, aVF, and V2-6
2) ST segment depression in lead aVR
