Sandbox/NCT

Characterize the symptoms: ❑ Asymptomatic ❑ Palpitations ❑ Dyspnea ❑ Fatigue ❑ Chest discomfort ❑ Lightheadedness ❑ Syncope ❑ Polyuria

Identify possible triggers: ❑ Infection ❑ Caffeine ❑ Alcohol ❑ Nicotine ❑ Recreational drugs ❑ Hypovolemia ❑ Hyperthyroidism ❑ Hypoxia ❑ Acidosis ❑ Hypokalemia ❑ Hyperkalemia ❑ Hypoglycemia ❑ Hypothermia ❑ Toxins ❑ Cardiac tamponade ❑ Pulmonary embolism ❑ Coronary thrombosis ❑ Trauma

Differential Diagnosis ❑ AV nodal reentrant tachycardia (AVNRT) ❑ Atrioventricular reentrant tachycardia (AVRT) ❑ Junctional tachycardia ❑ Sinus tachycardia ❑ Inappropriate sinus tachycardia ❑ Sinus node re-entry tachycardia ❑ Intraatrial reentrant tachycardia (IART) ❑ Atrial tachycardia ❑ Multifocal atrial tachycardia ❑ Atrial fibrillation ❑ Atrial flutter

Examine the patient: General appearance ❑ Diaphoretic ❑ ill-appearing Vitals ❑ Pulse ❑ Rate ❑ Tachycardia ❑ Rhythm ❑ Regular ❑ Irregularly irregular ❑ Strength ❑ Weak ❑ Alternating in strength ❑ Respiration ❑ Tachypnea ❑ Blood pressure ❑ Hypotension (due to decreased ventricular filling) Skin ❑ Inspection ❑ Pallor Neck ❑ Elevated jugular venous pressure Cardiovascular examination ❑ Auscultation ❑ Heart sounds: showing rapid regualr or irregular pulse, depending on the type of arrhythmia and might be asscoiated with murmurs if there is an underlying cardiac disease

❑ Assess hemodynamic stability ❑ Monitor the blood pressure ❑ Monitor the heart rate ❑ Order and monitor the ECG ❑ Assess and support airway, breathing and circulation (ABC) ❑ Give oxygen if needed

❑ Unstable patient

❑ Stable patient

❑ If the rythm isn't sinus tachycardia: Urgent cardioversion

❑ If the rythm is sinus tachycardia: Focus your treatment on the underlying condition. If it is due to cardiac ischemia or aortic stenosis, control heart rate by IV metoprolol at the rate of 5 mg/2 minutes till full control or till the maximum of 15 mg, then shift to oral regimen. Don't adminster beta blockers if the patient has significant bradycardia (<50 beats per minute)

Documented arrhythmia

Undocumented arrhythmia (ECG is normal)

❑ Confirm diagnosis of narrow QRS complex tachycardia (heart rate > 100 beats per minute associated with a QRS complex duration < 120 milliseconds) ❑ Identify and treat SVT

History suggestive of extra premature beats ❑ Sensation of a pause followed by a strong heart beat OR ❑ Irregularities in heart rhythm

History suggestive of paroxysmal arrhythmia ❑ Regular palpitations with sudden onset and termination

Rule out the following: ❑ Caffeine ❑ Alcohol ❑ Nicotine ❑ Recreational drugs ❑ Hyperthyroidism

❑ Refer for an invasive electrophysiological study AND/OR ❑ Catheter ablation ❑ Educate about vagal maneuvers ❑ Consider beta blocker

Differential Diagnosis

Type of Arrhythmia	EKG (lead II)†	Clues
Supraventricular tachycardia		Any tachyarrhythmia that is initiated and maintained in atrial tissue or atrioventricular junctional tissue.
Sinus tachycardia		Rhythm with heart rate > 100 bpm, originating in SA node due to its increased automaticity.
Sinus node re-entry tachycardia		Rare paroxysmal tachycardia arising due to re-entry circuits with in SA node.
Atrial fibrillation		Supraventricular tachycardia with irregularly irregular rhythm and absent P waves on EKG.
Atrial flutter		Cardiac rhythm characterized by an atrial rate ranging from 240 to 400 beats per minute and regular continuous wave-form.
AVNRT		Most common form of PSVT with a heart rate of 140-250 bpm, re-entrant circuit involves two separate anatomical pathways (slow and fast) loacted in perinodal tissue.
AVRT		Re-entrant tachycardia occurring due to an accessory pathway in addition to AV node, accessory pathway is essential for the initiation and the maintenance of tachycardia.
Focal atrial tachycardia		Focal atria tachycardia refers to a rhythm originating from a single site either in the left or right atrium with an atrial rate of 100-250 bpm.
Nonparoxysmal junctional tachycardia		Benign tachycardia occurring due to increased automaticity arising from a high junctional focus.
Multifocal atrial tachycardia		Irregular tachycardia characterized by 3 different P wave morphologies on EKG.

† EKG strips is a courtesy from ECGpedia.

References

Template:WikiDoc Sources