Simplified Intracardiac Electrocardiography forEbstein’s Anomaly

David Holmes, MD, and Morton J. Kern, MD

Key words: Ebstein’s anomaly; electrocardiography

INTRODUCTION

Although infrequent, invasive diagnosis and confirma-tion of an Ebstein’s anomaly is helpful. Use of simulta-neous hemodynamics and an intracardiac electrogramcan establish the diagnosis of ventricularized atrial tissuebut required specialized pacing-type catheters incorpo-rating an electrode into an end-hole catheter. We describea simplified method to obtain this information.

CASE REPORT

A 30-year-old woman with two uneventful pregnanciesand no other past medical history came to the emergencyroom for evaluation of 2 days of intermittent severe sub-sternal chest pressure. The physical examination was nor-mal. An electrocardiogram showed a short P-R interval witha wide QRS complex of the Wolff-Parkinson-White pattern.After admission to the hospital, a transthoracic 2D echocar-diogram demonstrated an enlarged right atrium, apical dis-placement of the tricuspid valve into the right ventricle, andsevere tricuspid regurgitation (Fig. 1, top right). No atrialseptal defect (ASD) or patent foramen ovale (PFO) werefound during the echo contrast study. Right and left heart

catheterization was then performed. Right atrial pressurewas elevated (8 mm Hg). Right ventriculography demon-strated severe tricuspid regurgitation and an enlarged rightatrium (Fig. 1, top left).

To record an intracardiac electrogram, a 0.014� ChoiceFloppy angioplsty guidewire (Boston Scientific/Scimed,Maple Grove, MN) was placed in the lumen of a 6 Frmultipurpose catheter with the spring tip minimally pro-truding. The proximal end of the guidewire was attachedto a surface V1 ECG lead with a sterile alligator clamp.During continuous electrocardiographic and pressuremonitoring, the catheter was manually withdrawn fromthe right ventricle into the right atrium (Fig. 1, bottomleft). Figure 1, bottom right, demonstrates electrocardio-graphic evidence of ventricularization of the right atrium,manifested by an atrial ECG despite ventricular pressurewaveforms.

DISCUSSION

The use of the guidewire connected to V1 simplifiesmeasurement of intracavitary electrocardiograms. Thetransition of the right ventricular pressure to rightatrial pressure in the presence of a continuous rightatrial electrogram is a classic finding of Ebstein’sanomaly.

J. Gerard Mudd Cardiac Catheterization Laboratory, St. LouisUniversity Health Sciences Center, St. Louis, Missouri

*Correspondence to: Dr. Morton J. Kern, J. Gerard Mudd CardiacCatheterization Laboratory, St. Louis University Health Sciences Cen-ter, 3635 Vista Avenue at Grand Boulevard, St. Louis, MO 63110.E-mail: kernm@slu.edu

Received September 2001; Revision accepted 3 October 2001

Catheterization and Cardiovascular Interventions 55:367–368 (2002)

© 2002 Wiley-Liss, Inc.DOI 10.1002/ccd.10094

Fig. 1. Top left: Right ventriculogram using a balloon-tippedcatheter demonstrates a small right ventricle and large rightatrium with tricuspid regurgitation. Top right: Two-dimensionalechocardiogram (four-chamber view) showing apical displace-ment of the tricuspid valve into the right ventricle. Bottom left:A 6 F-multipurpose catheter with a 0.014� angioplasty wire (at-

tached to an alligator clip to lead V1) was used to obtain anintracavitary electrogram and simultaneous hemodynamics.Bottom right: Simultaneous intracavitary electrogram and he-modynamic recording during catheter withdrawal illustratingthe pressure change from right ventricle to atrium with nochange in the atrial electrogram.

368 Holmes and Kern