Represents SA node

60-100bpm

atrial depolarization

The bundle branch system

Baseline. Occurs after complete depolarization and repolarization.

delay of electrical signal caused by T-Cells of AV node

Ventricular repolarization

0.04-0.10 Sec.

Ventricular depolarization

0.30-0.44 Sec. 

complete depolarization and repolarization

# of QRS Complexes within 6 Seconds and multiply by 10

(Least accurate but the method of choice for irregular rhythms)

Count the # of big blocks between the same point on two consecutive QRS complexes, and divide into 300

(most accurate method)

Consistant P wave before each QRS complex

0.12-0.20 PR interval

0.04-0.10 QRS duration

Anxiety, fear, physical activity, stress, fever, hypoxemia, hyperthyroidism, *catecholamines, atropine, caffeine, nicotine

SOB, decreased o2, JVD, decreased urine output, restlessness

SA node discharge less than 60bpm

Causes: syncope, hypotension, diaphorisis, ventricular ectopy, anginal pain

*Atropine*

administer 02, external pacemaker, volume replacement

Rapid stimulation to the atrial tissue 100-280 bpm

re-entry mechanism where impulse circulates repeatedly

Vagal manuveurs, oxygen, synchronized cardioversion,

*cardizem, or Adenocard*

Most common dyrhythmia. It is multiple rapid impulses from many atrial foci depolarize the atria in a totally disorganized manner rate 350-600bpm

no clear p wave, loss of atrial "kick"

Biggest= HTN,

DM, male gender, CHF, and valvular disease

*Cardizem or amiodarone*

anticoagulants, cardioversion (atrial clots are a contraindication), radio frequency, catheter ablation, bi-ventricular pacing, maze procedure

Rapid atrial depolarization occuring at a rate of 250-350bpm

AV node blocks the number of impulses that reach the ventricules as a protecive mechanism.

S/S: palpitations, nervousness, angina, heart failure, shock

Treatment: *Cardizem or Amiodarone*

Anticoagulants, cardioversion, radiofrequency, catheter ablation, bi-ventricular pacing, maze procedure.

Repetitive firing of an irritable ventricular eptopic focus. Rate 140-180bpm

Causes CARDIAC ARREST

at risk: ischemic heart disease, MI, cardiomyopathy, hypokalemia, valvular heart disease, heart failure.

ASSESS: ABCs, LOC, 02 level

TREATMENT: *mexital or betapace*

S/S:loss of consciousness, no BP, no respirations

Ventricular standstill. complete absense of any ventricular rhythm.

full cardiac arrest

TREATMENT: CPR immediately,

*DO NOT SHOCK ASYSTOLE*

Thickening by fibrosis. Rheumatic Fever is the most common cause. Valve opening narrows preventing normal blood flow from LA to LV.

Pulmonary congestion and right-sided HF occur.

Dyspnea upon exertion, othopnea, paroxymal nocturnal dypnea, palpitations, dry cough

rumbling apical diastolic murmur

The fibrotic and calcific charnges prevent the mitral valve from closing completely during systole.

*Rheumatic heart disease #1 cause*

*affects women more than men*

*High pitched systolic murmur heard @ Apex*

Valvular leaflets enlarge & prolapse into LA during systole. Asymptomatic

*midsystolic click &late systolic murmur audible at apex

Most common cardiac valve dysfunction. the aortic valve orifice narrows & obstructs left ventricular outflow during systole.

S/S: Dyspnea, angina upon exertion

Narrow pulse pressure noted when BP is measured

S/S: paroxysmal nocternal dyspnea, noturnal angina w/diaphoresis, bounding arterial palpated pulse

Causes: HTN, endocarditis, valvular abnormalities, marfan syndrome

Repair Surgical Management

Balloon Valvuloplasty

Usually the initial treatment for people with noncalcified, mobile mitral valves. Usually older and are at high risk for surgical complications or have refused operative treatment.