Others Flashcards
Diffuse T wave peaking and prolonged PR interval that eventually disappears followed by QRS waves that merge with T waves is diagnostic of
Hyperkalemia
Hyperkalemia can cause…
V-fib & Death
ST segment depression
Flattening of Twave
and U waves are diagnostic of
Hypokalemia
Hypocalcemia does what to the QT interval?
Prolongs QT Interval
Hypercalcemia does what to the QT interval?
Shortens the QT Interval
Hypocalcemia can lead to what arrhythmia?
Torsades de pointes
What are the usual causes of hypomagnesemia?
GI or renal losses
What electrolyte disorder can cause hypokalemia, ventricular arrhythmias w/acute MI, digoxin toxicity, worsens hypocalcemia, and torsades de pointes?
Hypomagnesemia
Severe hypermagnesemia shows what EKG changes
Prolonged PR and QRS intervals
What are J waves (Osborn waves)
See an abrupt ascent at J point and then a sudden plung to baseline
Prolonged intervals and segments and appearance of J waves are diagnostic of
Hypothermia
Asymmetric ST segment depression and flattening/inversion of T waves is seen in
Therapeutic digitalis levels
When using digitalis _____ is more likely seen in patients with sick sinus syndrome
sinus node suppression
Which is a more significant measure of potassium levels: EKG or serum levels?
EKG changes are more significant
A dialysis patient comes to the ER and voices that they skipped their last two dialysis appointments. What EKG changes might you expect to see on the EKG?
Hyperkalemia:
Diffuse t wave peaking
PR interval prolonging
QRS widening- sine wave pattern
What are common causes to hypermagnesemia?
Renal failure or excessive intake
What can hypermagnesemia cause
cardiac arrest
Are U waves diagnostic of hypokalemia?
No, may be seen in other conditions and those with normal hearts
In general, if a T wave is upright, a following U wave is_____
Also upright
-usually same axis
When is digitalis most effective at slowing HR?
When sitting or lying, commonly lost during exertion
What can digitalis toxicity cause?
First, Second, and Third Degree Heart Block
PAT and PVC most common tachyarrhythmias
PAT w/second degree AV block is most common
What is the most common cause of PAT w/block
Digitalis toxicity
What body temp brings about EKG changes in hypothermia?
<30C
What mimics atrial flutter in hypothermia?
muscle tremor artifact
What is the most common arrhythmia seen during hypothermia?
slow atrial fibrillation
At what percent QT lengthening do you d/c drug that causes QT interval lengthening
Prolonged more than 25% from pts baseline
Therapeutic digitalis changes best seen in what leads?
V5 V6
What things can prolong the QT interval?
Inherited Disorders Many antiarrhythmics Tricyclic antidepressants Phenothiazines Erythromycin Quinolone antibiotics Various antifungals
Two most common tachyarrhythmias in digitalis toxicity
PAT and PVCs
What cardiac cause shows dampening of electrical output shown in all leads?
Effusion, from pericarditis possibly
Diffuse ST elevation that after returning to baseline shows T wave inversion
Sometimes with PR interval depression is diagnostic of
Pericarditis
What is electrical alternans?
Heart is rotating within its fluid filled sac from excess effusion
EKG axis varies with each beat
Patients with inherited QT intervals should be restricted from what?
Competitive sports and meds that prolong interval
Patients with inherited QT intervals often treated with
Beta blockers and implantable defibrillators
Correct QTc most accurate with what heart rates
50-120 bpm
Specific or nonspecific: Flattening of T waves
nonspecific
Specific or nonspecific: tented T waves
specific- hyperkalemia
Specific or nonspecific: slightly inverted t waves
nonspecific
Specific or nonspecific: deep t wave inversions
specific- usually ischemia
What differentiates pericarditis from MI?
Diffuse in pericarditis
T wave inversion only after ST segments back to baseline in pericarditis
No Q waves in pericarditis
PR depression in pericarditis
A patient with hypertrophic obstructive cardiomyopathy may have
LVH
left axis deviation
Q waves laterally and occasionally inferiorly
Myocarditis can cause
conduction blocks
-esp bundle branch blocks & hemiblocks
What is myocarditis?
Diffuse inflammatory process of the myocardium
COPD can show what EKG changes
low voltage
right axis deviation
poor R wave progression in precordials
COPD can cause/lead to
chronic cor pulmonale
right sided CHF and will show right atrial enlargement (P pulmonale)
RVH with repolarization abnormalities
S1Q3T3 pattern is diagnostic of
Pulmonary Embolism
What EKG changes can be seen in acute pulmonary embolism?
Pattern of RVh w/repolarization changes
RBB
S1Q3T3
arrhythmias
What are the most common arrhythmias seen in PE?
sinus tachycardia &atrial fibrillation
Diffuse deep symmetrical T wave inversion and prominent U waves are diagnostic of
Subarachnoid bleed or cerebral infarction
What is the most common cause of sudden cardiac death?
Coronary artery disease/atherosclerosis causing an infarction or arrhythmia
What types of drug abuse can cause sudden cardiac death?
Cocaine and amphetamines
What is commotion cordis?
blunt force to the chest causing v-fib possibly leading to sudden cardiac death
ie- baseball player with healthy heart that gets a ball directly to the chest
What is constriction of the artery by surrounding tissue exacerbated by increased myocardial contractions during exercise causing v-fib?
Anomalous origin of the coronary arteries
-can cause sudden cardiac death
What genetic mutation affects voltage dependent sodium channels during repolarization commonly seen in men in 20s and 30s?
Brugada Syndrome
What EKG changes are diagnostic of Brugada Syndrome?
RBB
BST segment elevation in V1-V3
When is sudden death most likely to occur in patients with Brugada Syndrome?
during sleep
What can Brugada syndrome cause
Ventricular arrhythmias that can cause sudden death
-commonly fast polymorphic v-tach that looks like torasades
In athletes hearts, are the most common causes of heart disorders?
Heart muscle disorders and sudden ventricular arrhythmias
True or False: Athletes are at an increased risk for sudden cardiac death compared to non-athletes
True
