Cardio Exam 3

A positive (i.e., upright) P wave before each QRS
complex, P waves that look alike, A constant PR interval, A regular atrial and ventricular rhythm (usually), are characteristics of a wave that begins in the _____ node

SA

the name given to a normal heart rhythm

sinus

In adults and adolescents, the SA node usually fires at a regular rate of____________ beats per minute

60-100

If the SA node fires at a rate slower than normal for the patient’s age, the rhythm is called

sinus bradycardia

Rate less than 40 beats/min

severe sinus bradycardia

sinus bradycardia occurs during

sleep

sinus bradycardia is common in what group of patients

well-conditioned athletes

if sinus bradycardia is asymptomatic, what is the treatment

no treatment

Blocks chemicals at endings of vagus nerves, allows more sympathetic activity

atropine

If the SA node fires at a rate faster than normal for the patient’s age, the rhythm is called

sinus tachycardia

Looks like a sinus rhythm only faster, at very fast rates, it may be hard to tell the difference
between a P wave and T wave describes

sinus tachycardia

Occurs for no apparent physiologic cause, heart rate may rapidly increase to more than 100 beats/min with minimal exertion, at rest, or both. Accompanying symptoms are usually nonspecific.

inappropriate sinus tachycardia

which sinus tachycardia treatment is directed towards correcting the underlying cause

physiologic

which sinus tachycardia treatment is directed towards lifestyle modifications

inapporpriate

When the SA node fires irregularly, the resulting rhythm is called

sinus arrhythmia

Associated with the phases of breathing and changes in intrathoracic pressure

respiratory sinus arrythmia

Associated with phases of breathing and changes in intrathoracic pressure. Most commonly observed in children and young adults

respiratory sinus arrhythmia

Can be seen in people with normal hearts but is more likely to be found in older individuals and in those with heart disease. Common after inferior wall MI. May be seen with increased intracranial pressure. May be a result of the effects of medications or carotid sinus pressure

nonrespiratory sinus arrythmia

does sinus arrythmia usually require treatment

no

if sinus arrythmia is associate with hemodynamic compromise what treatment can be used

IV atropine

Disorder of impulse conduction, SA node generates impulses, impulses are blocked as they exit the SA node, results in periodically absent PQRST complexes

sinoatrial block

what medications cause sinoatrial block

Digitalis, quinidine, procainamide, or salicylates

if hemodynamic compromise is present with a sinoatrial block, besides atropine what can be done to treat?

pacemaker

Disorder of impulse formation. The SA node’s pacemaker cells do not initiate an
electrical impulse for one or more beats, results in absent PQRST complexes

sinus arrest

Most often affects adults over age 70, usually related to degenerative SA node tissue
changes. On the ECG, ________ can appear as alternating patterns of bradycardia and tachycardia (bradycardia-tachycardia syndrome) or skipped beats caused by episodes of SA block or sinus arrest

sick sinus syndrome

diagnosis of SSS usually requires ______ monitoring

Holter

glucose normal range

70-110 g/dL

BUN normal range

7-25

creatinine normal range

0.2-1.5 mg/dL

sodium normal range

135-145 (mEq/L)

Potassium normal range

3.5-5.0 mmol/L

troponin normal range

3-54 pg/ml

normal WBC

5.0-10.0 thousand

normal RBC

4.2-6.2 mil

normal hemoglobin count for women

12-16 g/dL

normal hemoglobin count for men

14-18 g/dL

normal hematocrit

36-53%

normal platelet count

150-450 thousand

normal activated partial thromboplastin time range

24-40

normal prothrombin time range

10.4-13.0

average international normalized ratio range

0.75-1.2

average pH

7.35-7.45

normal pCO2

35-45 mmHg

normal paO2

80-100 mmHg

normal HCO3

21-28 mmol/L

normal O2 stat

94-100%

Altered automaticity and triggered activity are disorders in impulse ________

formation

Reentry is a disorder in impulse _________

conduction

T or F: most atrial dysrhythmias are life threatening

false

Premature beats are identified by their ______ _ _____

site of origin

PACs stands for

premature atrial complexes

PJCs stand for

premature junction complexes

PVCs stand for

premature ventricular complexes

two premature beats in a row

couplet

three or more premature beats in a row

runs or bursts

every other beat is premature

bigeminy

every third beat is a premature beat

trigeminy

every fourth beat is a premature beat

quadrigeminy

Occur when an irritable site within the atria discharges before the next SA node impulse is due to discharge

PAC

PAC ECG

A ____________ pause is present if the period between the complex before and after a premature beat is the same as two normal R-R intervals

compensatory

• Early (premature) P waves

• Positive (upright) P waves (in lead II) that differ in shape from sinus P waves

• Early P waves that may or may not be followed by a QRS complex

PACs (premature atrial contraction)

PACs associated with a wide-QRS complex are called

aberrantly conducted

blocked or nonconducted PAC

When wandering atrial pacemaker is associated with a ventricular rate faster than 100 beats/min, the rhythm is called

multifocal atrial tachycardia

Exact mechanism of ________ is unknown but may involve altered automaticity or triggered activity

MAT (multifocal atrial tachycardia)

begin above the bundle of His; include rhythms that begin in the SA node, atrial tissue, or the AV junction. rhythms with a ventricular rate faster than 100 beats/min at rest

supraventricular tachycardia

T or F: Some SVTs need the AV node to sustain the rhythm, and some do not

true

atrial tachycardia with 2:1 block

Carotid sinus massage, Application of a cold stimulus to the face, and Valsalva maneuver are all considered _______ maneuvers

vagal

What medication can interrupt reentry pathways involving the AV node, Rapid onset of action, short half-life

adenosine

Delivery of an electrical shock to the heart timed to occur during QRS

synchronized cardioversion

atrial ventricular nonreentrant tachycardia (AVNRT)

Results from a reentry circuit that uses two separate pathways leading into the AV node

AV node reentrant tachycardia

Ectopic atrial rhythm in which an irritable site within the atria fires regularly at a very rapid rate

atrial flutter

Occurs because of altered automaticity in one or several rapidly firing sites in the atria or reentry involving one or more circuits in the atria

atrial fibrilation

A-fib

Ventricular rhythm usually irregularly irregular

Atrial rate usually 300 to 600 beats/min; ventricular rate variable

No identifiable P waves, fibrillatory waves present; erratic, wavy baseline

PR interval:  Not measurable

QRS duration:  0.11 second or less unless abnormally conducted

A-fib

If the ventricles function as the heart’s pacemaker, they typically generate impulses at a rate of

20-40 bpm

Ventricular beats and rhythms are typically characterized by_____ ______ that are abnormally shaped and longer than normal Ventricular Depolarization

QRS complexes

Occurs earlier than the next expected beat of the underlying rhythm, QRS width is typically 0.12 second or greater, T wave is usually in the opposite direction of the QRS complex

premature ventricular complex

C shows

PVC

Result from an electrical impulse from a supraventricular site firing at the same time as an ectopic site in the ventricles. Do not resemble normally conducted beats, nor do they resemble true ventricular beats

fusion beats

every other beat is a PVC

Ventricular bigeminy

every third beat is a PVC

Ventricular trigeminy

Premature ventricular beats that look the same in the same lead and originate from the same anatomical site (focus)

PVC