Paroxysmal supraventricular tachycardia: Difference between revisions
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^In infants HR cuttoff = 220 | ^In infants HR cuttoff = 220 | ||
*Generally, troponins are not indicated in pts without significant risk factors for CAD<ref>Bukkapatnam et al. Relationship of myocardial ischemia and injury to coronary artery disease in patients with supraventricular tachycardia. Am J Cardiol. 2010 Aug 1;106(3):374-7.</ref> | |||
==Treatment== | ==Treatment== | ||
Revision as of 14:17, 16 September 2015
SVT terminology can be confusing, as some references consider SVT to be any rhythm originating above the ventricles (i.e. sinus tachycardia, MAT, atrial flutter, atrial fibrillation, PSVT, etc). As these entities have their own specific articles and treatment, only paroxysmal supraventricular tachycardia links here.
Background
- Also known as PSVT and frequently referred to just as SVT
- AV nodal reentrant tachycardia (AVNRT) and AV reentrant tachycardia (AVRT) are subtypes of PSVT
- Most common dysrhythmia in children
- Infants: poor feeding, tachypnea, and irritability
Clinical Presentation
- Palpitations
- May also present with haemodynamic instability if severe, eg hypotension, syncope
Differential Diagnosis
Palpitations
- Arrhythmias:
- Non-arrhythmic cardiac causes:
- Psychiatric causes:
- Drugs and Medications:
- Alcohol
- Caffeine
- Drugs of abuse (e.g. cocaine)
- Medications (e.g. digoxin, theophylline)
- Tobacco
- Misc
Diagnosis
| Symptoms | Sinus tachycardia | SVT |
| History | volume loss | sudden onset |
| Physical Exam | dehydated | CHF-like |
| ^Heart Rate | <180 | >180 |
| Variability | Yes | No |
^In infants HR cuttoff = 220
- Generally, troponins are not indicated in pts without significant risk factors for CAD[1]
Treatment
Unstable
- Synchronized cardioversion 0.5-1.0 J/kg
- Pediatrics: cardioversion at 0.5-1 J/kg. If unsuccessful, increase to 2 J/kg
- Consider giving sedation prior to cardioversion (unless in emergent situation)
Stable
- Pediatrics: often successful with ice application to face
- Carotid sinus massage (ideal duration of 15 seconds[2])
- Auscultate to r/o bruits in carotid artery before performing
- Perform ONE side at a time
- Valsalva maneuver (ideal duration of 10 seconds) and may be modified to be followed by laying the patient supine and performing passive leg raise to increase efficacy[3]
- 6mg IVP; 12mg IVP (if initial dose failed)
- Contraindicated in asthmatics
- Diltiazem 15–20mg IV over 2min
- May give 25mg IV if inadequate response after 15min
- If IV bolus worked start IV infusion at 5–20mg/hr
- Contraindications: Hypotension, CHF, any suspicion of VT
- Beta-blockers
- Metoprolol 5mg IV q5min x 3; give 50mg PO if IVP effective
- Esmolol 500mcg/kg IV over 60sec
- May give repeat bolus if inadequate response after 2-5min
- If effective start infusion at 50mcg/kg/min (titrate up to 300mcg/kg/min)
- Contraindicated in asthmatics
See Also
References
- ↑ Bukkapatnam et al. Relationship of myocardial ischemia and injury to coronary artery disease in patients with supraventricular tachycardia. Am J Cardiol. 2010 Aug 1;106(3):374-7.
- ↑ Appelboam, A, et al. Randomised Evaluation of modified Valsalva Effectiveness in Re-entrant Tachycardias (REVERT) study. BMJ, 2014; 4(3):e004525.
- ↑ Appelboam A. et al. Postural modification to the standard Valsalva manoeuvre for emergency treatment of supraventricular tachycardias (REVERT): a randomised controlled trial fulltext