CASE REPORT

Cardiac Resynchronization Therapy in Patients with Ebstein’s Anomaly A Case Report Genri Numata,1 MD, Eisuke Amiya,1 MD, Toshiya Kojima,1 MD, Katsuhito Fujiu,1,3 MD, Masaru Hatano,1,2 MD, Masafumi Watanabe,1 MD and Issei Komuro,1 MD

Summary Ebstein’s anomaly is a rare congenital heart disease characterized by apical displacement of the septal and posterior tricuspid valve leaflets. It is often complicated with left ventricular (LV) dysfunction as well as right- sided abnormalities. On the other hand, in the presence of LV dysfunction, right ventricular pacing is likely to aggravate the diseased LV function, which is termed pacemaker-induced cardiomyopathy. Thus, deteriorating ef- fects of RV pacing on cardiac function might be enhanced and result in pacemaker-induced cardiomyopathy in patients with Ebstein’s anomaly, even if they have preserved LVEF. Cardiac resynchronization therapy (CRT) is effective for the treatment of pacemaker-induced cardiomyopathy, and we present the first case of effect of CRT on pacemaker-induced cardiomyopathy associated with Ebstein’s anomaly. (Int Heart J Advance Publication) Key words: Pacemaker-induced cardiomyopathy

bstein’s anomaly is a rare congenital heart disease area, swelling of the lower legs, and cyanosis on her ex- characterized by apical displacement of the septal tremities. An electrocardiography revealed a first-degree E and posterior tricuspid valve leaflets. Classically, atrioventricular block and an alternating right and left Ebstein’s anomaly has been considered to cause right- bundle-branch block. A transthoracic echocardiogram sided heart failure secondary to right-sided heart abnor- showed displacement of septal and posterior tricuspid malities, but many patients have the complication of left- leaflet, an “atrialized” right ventricle, a dilated right sided heart abnormalities.1) In the presence of left ven- atrium, and moderate tricuspid valve regurgitation (Figure tricular (LV) dysfunction, right ventricular (RV) pacing is 1A). The patent foramen ovale was not identified and her likely to further aggravate the diseased LV function, left heart ejection fraction (EF) was preserved (Figure 1 which is termed pacemaker (PM)-induced cardiomyopa- B). In laboratory test, brain natriuretic peptide (BNP) in- thy.2,3) The risk factors and management of PM-induced creased to 1330 pg/mL. From these findings, she was di- cardiomyopathy have not yet been elucidated, but cardiac agnosed with exacerbated heart failure due to Ebstein’s resynchronization therapy (CRT) may be effective in pre- anomaly. After her hospitalization, the addition of diuret- vention and treatment.4) Few cases of PM-induced cardio- ics attenuated her symptoms of heart failure, and the level myopathy associated with congenital heart failure have of BNP decreased to 50 pg/mL. PM (DDD 70/120 beats been reported. We present the first case of effect of CRT per minute) was implanted for her alternating bundle- on PM-induced cardiomyopathy associated with Ebstein’s branch block and she was discharged. anomaly. One year later, her heart failure worsened again and her LV ejection fraction was markedly declined to 20% (Figure 1C). Atrial fibrillation (AF) was observed and her Case Report BNP increased to 2137 pg/mL. Because AF might con- A 76-year-old woman was admitted to our hospital tribute to the worsening of heart failure and her reduced with exacerbated palpitation and shortness of breath. At EF, a pulmonary vein isolation (PVI) was performed. Af- the age of 36 years, she had been diagnosed as Ebstein’s ter PVI, her BNP decreased to 578 pg/mL, and she was anomaly by echocardiogram, but she had rejected intra- discharged. cardiac repair because of no symptoms. A physical exami- However, PVI was not sufficient to stabilize her con- nation revealed a diastolic heart murmur on the apical dition and her heart failure re-exacerbate with low cardiac

From the 1Department of Cardiovascular Medicine, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan, 2Department of Therapeutic Strategy for Heart Failure, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan and 3Ubiquitous Health Informatics, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan. Address for correspondence: Eisuke Amiya, MD, Department of Cardiovascular Medicine, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8655, Japan. E-mail: [email protected] Received for publication November 17, 2016. Revised and accepted December 16, 2016. Released in advance online on J-STAGE September 30, 2017. doi: 10.1536/ihj.16-580 All rights reserved by the International Heart Journal Association. 1 IntHeartJ 2 Numata, ET AL Advance Publication

Figure 1. A: The apical displacement of the tricuspid valve and formation of an atrialized right ventricle in the four chamber view of transthoracic echocardiography. B-D: Left ventricular systolic function and left ventricular end-dia- stolic diameter (LVDd) before pacemaker implantation (B), after pacemaker implantation (C), and after cardiac resyn- chronization therapy (D). LVDd was increased after pacemaker implantation, and decreased after cardiac resynchroni- zation therapy. RV indicates right ventricle; and RA, right atrium. output syndrome. The level of BNP increased to ex- LV dysfunction in Ebstein’s anomaly is partly ex- tremely high with 3007 pg/mL. EF remained to be low plained by its vulnerable myocardium including noncom- (27%). Her dependency of pacing was 63.7% at that time paction, myocardial fibrosis, disruption of free wall myofi- and PM-induced cardiomyopathy was considered to be a bril continuity, fiber geometry, or mixed cardiac defect.5) principal cause for exacerbating heart failure, and CRT Besides, the dilated right ventricle itself has been thought device was implanted. to contribute to LV dysfunction, which is mostly observed After the intervention, QRS duration on ECG was in the presence of a significant left to right shunt congeni- shortened from 169 ms to 140 ms, and her symptoms im- tal heart disease. However, Goleski et al. demonstrated proved markedly. One month after CRT, BNP decreased that LVEF was not correlated to their LV shape, which to 484 pg/mL (Figure 2). Surprisingly EF was improved was distorted by right-sided dilatation, in patients with to 43% and the left ventricular end-diastolic diameter was Ebstein’s anomaly.5) Therefore, in patients with Ebstein’s reduced from 59 mm to 46 mm (Figure 1D, 2). This re- anomaly, there may be discordant mechanisms for LV markable reverse remodeling suggested CRT improved her shape and function abnormalities. PM-induced cardiomyopathy in a dramatic way. On the other hand, reduced LVEF and the depend- ency of the pacing (over 40%) are known to be the risk factors for the progression of PM-induced cardiomyopa- Discussion thy.2,6) It is evident by previous clinical trials (PACE, Ebstein’s anomaly commonly presents with right- BLOCK HF) that CRT should be recommended in the sided heart failure, however it is often complicated with presence of these two risk factors.7-9) However, there is not left ventricular dysfunction. Attenhofer et al. reported that enough data to recommend CRT in the setting of LV ab- left-sided heart failure was complicated during the natural normalities with preserved EF. Khurshid et al. reported course with Ebstein’s anomaly,1) and several investigators that CRT was appropriate for the prevention of PM- reported abnormal left ventricular shape, contractility, and induced cardiomyopathy in a wide native QRS duration reduced EF in these patients.5) (>115 ms) irrespective of reduced LVEF.10) However, even IntHeartJ Advance Publication CRT IN PATIENTS WITH EBSTEIN’S ANOMALY 3

BNP (pg/ml) LVEF (%) 3500 70 CRT

3000 60

2500 50

2000 40 LVEF 1500 30 BNP

1000 20

500 10

0 0 0 6 12 18 24 30 36

Months aŌer PM implantaƟŽn Figure 2. The change of brain natriuretic peptide (BNP) level and left ventricular ejection frac- tion (LVEF) after pacemaker (PM) implantation. BNP and LVEF significantly improved after car- diac resynchronization therapy (CRT). in the lacking of wide QRS or reduced EF, RV pacing is Disclosures presumed to alter geometry and function of the vulnerable LV through electrical and mechanical dysynchrony, and an Conflict of interest: The authors declare that they have increase LV end diastolic volume, leading to the LV sys- no conflict of interest. tolic dysfunction.3) In patients with Ebstein’s anomaly, these deteriorating effects of RV pacing on cardiac func- References tion might be enhanced and result in marked depression of LVEF even if they have preserved LVEF. 1. Attenhofer Jost CH, Connolly HM, Dearani JA, Edwards WD, In this patient, RV pacing is 63.7% of the time and Danielson GK. Ebstein’s anomaly. Circulation 2007; 115: 277- her left ventricular myocardium was presumably vulner- 85. (Review) 2. Ferrari AD, Borges AP, Albuquerque LC, et al. Cardiomyopathy able due to Ebstein’s anomaly, even if she had normal EF. induced by artificial cardiac pacing: myth or reality sustained She could be in a high-risk group of PM-induced cardio- by evidence? Rev Bras Cir Cardiovasc 2014; 29: 402-13. (Re- myopathy, and CRT may be effective for preventing cardi- view) omyopathy. 3. Guglin M, Barold SS. The role of biventricular pacing in the In some reports left ventricular reverse remodeling prevention and therapy of pacemaker-induced cardiomyopathy. 11) Ann Noninvasive Electrocardiol 2015; 20: 224-39. (Review) was observed in patients with CRT, and patients with et al PM-induced cardiomyopathy responded favorably to up- 4. Gierula J, Cubbon RM, Jamil HA, . Cardiac resynchroniza- 12) tion therapy in pacemaker-dependent patients with left ventricu- grading from RV pacing to CRT. In another randomized lar dysfunction. Europace 2013; 15: 1609-14. study for patients who needed permanent pacemaker with 5. Goleski PJ, Sheehan FH, Chen SS, Kilner PJ, Gatzoulis MA. mild reduced EF (40%), the CRT group had significant The shape and function of the left ventricle in Ebstein’s anom- improvements in exercise capacity, quality of life, and aly. Int J Cardiol 2014; 171: 404-12. LVEF compared with the RV pacing group.4) However, 6. Sakatani T, Sakamoto A, Kawamura K, et al. Clinical Outcome currently there is not enough data to recommend CRT for After Permanent Pacemaker Implantation in Patients With a High Percentage of Ventricular Pacing. Int Heart J 2015; 56: all patients who require PM support. Especially, in pa- 622-5. tients with Ebstein’s anomaly, there may be a high prob- 7. Yu CM, Chan JY, Zhang Q, et al. Biventricular pacing in pa- ability that deteriorating effects of RV pacing on cardiac tients with bradycardia and normal ejection fraction. N Engl J function result in marked depression of LVEF and we Med 2009; 361: 2123-34. need careful observation of it. More studies are needed to 8. Curtis AB, Worley SJ, Adamson PB, et al. Biventricular pacing reach the conclusion about the decision criteria of CRT for atrioventricular block and systolic dysfunction. N Engl J and define the patients at risk of PM-induced cardio- Med 2013; 368: 1585-93. 9. Yu CM, Fang F, Luo XX, Zhang Q, Azlan H, Razali O. Long- myopathy. term follow-up results of the Pacing to Avoid Cardiac Enlarge- ment (PACE) trial. Eur J Heart Fail 2014; 16: 1016-25. 10. Khurshid S, Epstein AE, Verdino RJ, et al. Incidence and pre- dictors of right ventricular pacing-induced cardiomyopathy. IntHeartJ 4 Numata, ET AL Advance Publication

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