MAIN TOPIC REVIEWS Hong-Euy Lim, MD, PhD Division of Cardiology, Korea University Guro Hospital, Seoul, Republic of Korea Surface electrocardiography of supraventricular tachycardia - differential diagnosis ABSTRACT Supraventricular tachycardia (SVT) is a common cardiac arrhythmia; it usually presents with recurrent episodes of tachycardia. Sudden-onset, rapid palpitations characterize SVT and, in most patients, a diagnosis can be made largely from patient history. But repeated attempts at electrocardiographic documentation of the arrhythmia may be useful for precise diagnosis and differentiation. Key words: supraventricular tachycardia electrocardiography Received: November 2, 2010 Revision Received: February 23, 2011 Accepted: March 30, 2011 Correspondence: Hong-Euy Lim, MD, PhD. Division of Cardiac Electrophysiology, Department of Internal Medicine, Korea University Cardiovascular Center, Korea University Guro Hospital, Korea University College of Medicine, 80, Guro-2-dong, Guro-gu, Seoul 152-703, Korea Tel: 82-2-2626-1046 (EPS Laboratory) Fax: 82-2-867-9093 E-mail: hongeuy@korea.ac.kr or h3lim@medimail.co.kr 23
Table 1. Classification of supraventricular tachycardia AV node-dependent arrhythmia AV nodal reentrant tachycardia AV reentrant tachycardia Junctional ectopic tachycardia AV node-independent arrhythmia Sinus tachycardia Sinus node reciprocating tachycardia Atrial tachycardia Multifocal atrial tachycardia Atrial flutter Atrial fibrillation AV; atrioventricular A B Figure 1. Differentiation of supraventricular tachycardia. ECG shows regular tachycardia with wide QRS complex (rate=150 bpm). P waves are negative in lead II, III and avf with 2:1 pattern (A). After adenosine 6 mg IV., ventricular rate became slower and then obvious P wave was observed (B). 24 Journal of Cardiac Arrhythmia
Figure 2. An ECG of atrioventricular nodal re-entrant tachycardia (AVNRT). ECG shows regular tachycardia with narrow QRS (rate=195 bpm). Retrograde P waves are seen just after QRS complexes. Pseudo S wave (red arrow) is observed in II, III and avf and pseudo R wave in V1. 25
Figure 3. An ECG of atrioventricular re-entrant tachycardia (AVRT). ECG shows regular tachycardia with narrow QRS (rate=234 bpm). Retrograde P waves are seen after QRS complexes. ST depression (>2.5 mm) is observed in lead V5 and V6, which reflect retrograde P wave (green arrow). 26 Journal of Cardiac Arrhythmia
A MAIN TOPIC REVIEWS B Figure 4. An ECG of atrial flutter (AFL). The ECG shows irregular tachycardia with narrow QRS (rate=102 bpm). Saw-tooth appearance F wave is observed in lead II, III and avf without isoelectrical line. This is an example of typical AFL (A). The ECG shows regular rhythm with narrow QRS (rate=72 bpm). F wave is negative in V1 and positive in lead II, III and avf. This is an example of atypical AFL (B). 27
Figure 5. An ECG of atrial tachycardia (AT). This is an example of long RP tachycardia. Obvious negative P waves are observed in lead II, III, and avf. V1 neg pos/neg neg/pos iso/pos iso pos V2-4 pos CT avl R.Septum Perinodal bifid in II &/or V1 yes no neg pos yes no CT neg in all inf.leads SMA CS os LS neg in all inf.leads sinus rhythm P wave yes no yes no pos +/- TA TA RAA CS Body LPV LAA CT RPV RPV Figure 6. A P-wave algorithm constructed on the basis of findings from 130 atrial tachycardias correctly localized the focus in 93% (Courtesy by Kistler PM, et al. JACC. 2006;48:1010-1017). CS; coronary sinus, CT; crista terminalis, LAA; left atrial appendage, LPV; left pulmonary vein, LS; left septum, RPV; right pulmonary vein, SMA; superior mitral annulus, TA; tricuspid annulus 28 Journal of Cardiac Arrhythmia
Figure 7. An ECG of atrial fibrillation (AF). Irregularly irregular RR intervals present without obvious P wave. This is an example of atrial fibrillation. 29
Table 2. Characteristics of supraventricular tachycardia Type of SVT Varieties Gender dominance Adenosine A:V ratio PR/RP in AV QRS complex AVNRT Slow-fast Female Stops 1:1 PR >> RP** Narrow 2:1* AVNRT Fast-slow Female Stops 1:1 PR < RP Narrow AVNRT Slow-slow Female Stops 1:1 PR > RP Narrow AVRT Orthodromic Male Stops 1:1 PR > RP Narrow conventional AVRT Antidromic Male Stops 1:1 PR = RP Wide, maximally conventional PR < RP pre-excited AT Focal Female Stops 90 % 1:1 or higher PR < RP Narrow of episodes PR = RP PR > RP*** AT Macro-reentrant Even No effect 2 :1 NA Narrow or higher RBBB if ASD AFL CTI CCW and CW Male No effect 2:1 NA Narrow or higher AFL Non-CTI Even No effect 2:1 NA Narrow or higher AFL; atrial flutter, ASD; atrial septal defect, AT; atrial tachycardia, AVNRT; atrioventricular nodal reentrant tachycardia, AVRT; atrioventricular reentrant tachycardia, BBB; bundle branch block, CCW; counterclockwise, CTI; cavo-tricuspid isthmus, CW; clockwise, SVT; supraventricular tachycardia * 2:1 ratio in AVNRT exceptional in the clinical scenario, ** P waves during slow-fast AVNRT are either hidden within the QRS complex or visible as a continuation of the QRS mimicking terminal s waves in inferior leads or r waves in V1, *** PR > RP if concomitant drugs acting on the AV node, if associated AV nodal disease or if AV conduction over a slow AV nodal pathway. (Adopted from The ESC textbook of cardiovascular medicine) References 1. Fox DJ, Tischenko A, Krahn AD, Skanes AC, Gula LJ, Yee RK, Klein GJ. Supraventricular tachycardia: diagnosis and management. Mayo Clinic proceedings. 2008;83:1400-1411. 2. Delacretaz E. Clinical practice. Supraventricular tachycardia. N 30 Journal of Cardiac Arrhythmia
Engl J Med. 2006;354:1039-1051. 3. Camm AJ, Luscher TF, Serruys PW, European Society of Cardiology. The ESC textbook of cardiovascular medicine. 2nd ed. Oxford ; New York: Oxford University Press; 2009. 4. Caroline M, Jonathan MK, Prediction of the atrial flutter circuit location from the surface electrocardiogram. Europace. 2008; 10:786-796. 5. Bochoeyer A, Yang Y, Cheng J, Lee RJ, Keung EC, Marrouche NF et al. Surface electrocardiographic characteristics of right and left atrial flutter. Circulation. 2003;108:60-66. 6. Jais P, Hocini M, Weerasoryia R, Macle L, Scavee C, Raybaud F et al. Atypical left atrial flutter. Cardiac Electrophysiol Rev. 2002;6:371-377. 7. Peter MK, Kurt CR, Harris MH, Simon PF, Suresh S, Jitendra KV, Joseph BM, Paul BS, Jonathan MK. P-wave morphology in focal atrial tachycardia. J Am Coll Cardiol. 2006;48:1010-1017. MAIN TOPIC REVIEWS 31