Overview
Paroxysmal tachycardia encompasses various types of episodic rapid heart rhythms, including atrioventricular (AV) nodal reentrant tachycardia, reciprocating tachycardias, and sinus node reentrant tachycardias, often requiring specific diagnostic and therapeutic approaches.Diagnosis
Electrophysiological studies: Essential for identifying mechanisms such as accessory pathways, dual AV nodal pathways, and sinus node reentry 1467.
Transesophageal atrial pacing (TAP): Useful for predicting antiarrhythmic drug efficacy by assessing tachycardia inducibility 1.
Electrocardiogram (ECG) analysis: Evaluating PR interval, AH interval, and QRS morphology aids in diagnosing accessory pathways 8.
Atrial and His bundle pacing: Can normalize QRS complexes and terminate tachycardia in cases with accessory pathways 4.Management
Antiarrhythmic drugs:
- Procainamide: Effective for termination when administered orally shortly after tachycardia onset; dose 25 mg/kg 2.
- Verapamil: Suppresses sinus node reentry in certain cases 7.
- Propranolol: Used for managing refractory cases, though efficacy may vary 3.
Pacing techniques:
- Autodecremental pacing: Utilized to terminate tachycardias through controlled pacing sequences 5.
- Dual-demand pacing: Implanted pacemakers programmed to switch to fixed-rate pacing to terminate reciprocating tachycardias 10.
Surgical interventions: Considered for refractory cases unresponsive to pharmacological therapy, such as subtotal right atrial exclusion 3.Special Populations
Pediatrics: Procainamide effective in young patients with non-life-threatening tachycardias 2.
Elderly: Specific considerations for drug dosing and side effects apply, though direct evidence is limited in abstracts provided.
Comorbidities: Management may need adjustment in presence of conditions like sinus node disease or ischemia 7.Key Recommendations
Utilize electrophysiological studies for definitive diagnosis and mechanism identification of paroxysmal tachycardia (Evidence: Strong 1467).
Employ transesophageal atrial pacing to predict the efficacy of antiarrhythmic therapy in narrow QRS complex tachycardias (Evidence: Moderate 1).
Consider autodecremental pacing as a modality for terminating complex paroxysmal tachycardias in refractory cases (Evidence: Weak 5).
In refractory cases, explore surgical interventions like subtotal right atrial exclusion (Evidence: Expert opinion 3).
Administer procainamide orally at 25 mg/kg for rapid termination of paroxysmal tachycardia when administered promptly post-onset (Evidence: Moderate 2).References
1 Kulakowski P, Dluzniewski M, O'Nunain S, Camm AJ, Wardzynska M, Ceremuzynski L. The value of transesophageal atrial pacing in predicting the efficacy of antiarrhythmic drugs in patients with paroxysmal narrow QRS complex tachycardia. Pacing and clinical electrophysiology : PACE 1992. link
2 Benson DW, Dunnigan A, Green TP, Benditt DG, Schneider SP. Periodic procainamide for paroxysmal tachycardia. Circulation 1985. link
3 Yee R, Guiraudon GM, Gardner MJ, Gulamhusein SS, Klein GJ. Refractory paroxysmal sinus tachycardia: management by subtotal right atrial exclusion. Journal of the American College of Cardiology 1984. link80026-1)
4 Heddle WF, Tonkin AM. Atrial and His bundle stimulation with an accessory nodo-ventricular connection. Pacing and clinical electrophysiology : PACE 1980. link
5 Ward DE, Camm AJ, Gainsborough J, Spurrell RA. Autodecremental pacing--a microprocessor based modality for the termination of paroxysmal tachycardias. Pacing and clinical electrophysiology : PACE 1980. link
6 Bauernfeind RA, Ayres BF, Wyndham CC, Dhingra RC, Swiryn SP, Strasberg B et al.. Cycle length in atrioventricular nodal reentrant paroxysmal tachycardia with observations on the Lown-Ganong-Levine syndrome. The American journal of cardiology 1980. link90472-5)
7 Curry PV, Evans TR, Krikler DM. Paroxysmal reciprocating sinus tachycardia. European journal of cardiology 1977. link
8 Greene HL. Accessory atrioventricular conduction syndromes: a review. The Johns Hopkins medical journal 1976. link
9 Massing GK, Waldo AL, James TN. Spontaneous atrial premature depolarizations during paroxysmal reentrant tachycardia. Journal of electrocardiology 1976. link80073-8)
10 Krikler D, Curry P, Buffet J. Dual-demand pacing for reciprocating atrioventricular tachycardia. British medical journal 1976. link