2100 ROUTINE RECORD A34-year-oldwomanwithWolff …

[Pages:4]Circulation: Arrhythmia and Electrophysiology ? CHALLENGE OF THE WEEK

HALSTEAD, HEATHER

ID:9942875899

26-JAN-2017 03:15:34

BJH-2100 ROUTINE RECORD

A 34-year-old woman with Wolff-Parkinson-White (WPW) 34yr Female Caucasian

Vent. rate PR interval

74 BPM 184 ms

Normal sinus rhythm T wave abnormality, consider inferior ischemia

QRS duration

74 ms

When compared with ECG of 25-JAN-2017 21:41,

Room:

QT/QTc

414/459 ms

No significant change was found

syndrome underwent radiofrequency catheter ablation of Loc:9

P-R-T axes

53 47 -21

This ECG was personally interpreted by the attending physician indicated below Confirmed by BARGER M.D., PHILIP (2922) on 1/27/2017 3:02:17 PM

atriovenTtecrhniccianu:KDlar accessory pathway. She is asymptomatic and Test ind:

hemodynamically stable. PostRefearredbby:lation ECG is shown in Figure Confirmed By: PHILIP BARGER M.D. 1.

I

aVR

V1

V4

II

aVL

V2

V5

III

aVF

V3

V6

V1

II

V5

2F5migm/us re10m1m./mPV os15t0-Haz bl7a.1.1tio1n2SLe24l1eHcDtCrIoD:c36a3 rdiogram (ECG)

Noheria A. Challenge of the Week: June 3rd Question

SID: 110006245972 EID:2922 EDT: 15:02 27-JAN-2017 ORDER: Page 1 of 1

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Circulation: Arrhythmia and Electrophysiology ? CHALLENGE OF THE WEEK

Which of the following is the most likely explanation for the ECG in Figure 1?

Answer options A. Ablation of right superior accessory pathway B. Ablation of right inferior accessory pathway C. Ablation of epicardial coronary sinus/venous

accessory pathway D.Ablation of left lateral accessory pathway E. Inferior wall ischemia

Noheria A. Challenge of the Week: June 3rd Question

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Circulation: Arrhythmia and Electrophysiology ? CHALLENGE OF THE WEEK

ANSWER TO JUNE 3rd QUESTION B. Ablation of right inferior accessory

pathway

Explanation The ECG in Figure 1 shows sinus rhythm with narrow QRS complexes without preexcitation. T-wave inversions are seen after ablation of WPW due to T wave memory.

Cardiac memory: In general, electrical remodeling with any chronic QRS configuration (preexcitation, pacing, bundle branch block etc.) pulls the repolarization vector in the direction of the QRS polarity. Immediately after ablation, the accessory pathway (AP) conduction is eliminated resulting in normalization of the QRS. However, the repolarization changes persist for 1-4 weeks before normalizing.1

Localization of T-wave memory vector: Cardiac memory results in T-wave inversions in leads where pre-ablation QRS was negative, proportional to the amplitude of the negative QRS complex.1 In Figure 1, T waves are inverted in lead III > lead II, and flattened in

lead II. This corresponds to the pre-ablation delta wave polarity most negative in lead III (Figure 2). This suggests a right inferior AP.2

Right superior AP will have an inferior axis and memory T-wave inversions in aVR and aVL, and epicardial coronary sinus/venous AP will have negative lead II and memory T-wave inversion in lead II. Left lateral AP will have a negative delta wave in lead I, but often the preexcitation in sinus rhythm is limited and insufficient to affect the overall QRS polarity, and thus may not result in memory T-wave inversions. Coronary ischemia can also result in T-wave inversions and should be kept in the differential diagnosis, but in this case T-wave memory is the more likely cause.

REFERENCES 1. Shvilkin A. Cardiac Memory: From Electrical

Curiosity to Clinical Diagnostic and Research Tool. In: Electrical Diseases of the Heart. London: Springer, London; 2013. p. 415?433. 2. Arruda MS, McClelland JH, Wang X, et al. Development and validation of an ECG algorithm for identifying accessory pathway ablation site in Wolff-Parkinson-White syndrome. J Cardiovasc Electrophysiol. 1998;9:2?12.

Noheria A. Challenge of the Week: June 3rd Answer

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CirculatioTTneecsth:innidcAi:an:rKDrhythmia and Electrophysiology ? CHALLENGE OF THE WEEK

Referred by:

Confirmed By: PHILIP BARGER M.D.

I

aVR

V1

V4

II

aVL

V2

V5

III

aVF

V3

V6

Figure 1. Post-ablation ECG. Maximum T wave inversion is seen in lead III (arrow).

V1

II

V5 25mm/s 10mm/mV 150Hz 7.1.1 12SL 241 HD CID: 363

SID: 110006245972 EID:2922 EDT: 15:02 27-JAN-2017 ORDER: Page 1 of 1

Figure 2. Pre-ablation ECG. Preexcited QRS complexes with most negative lead III (arrow). Cardiac memory results in leads with a negative QRS showing T wave inversions in postablation ECG in Figure 2.

Noheria A. Challenge of the Week: June 3rd Answer

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