Early onset "electrical" heart failure in myotonic dystrophy type 1 patient: the role of ICD biventricular pacing/Miyotonik distrofi tip 1 hastada erken baslayan "elektriksel" kalp yetersizligi: ICD biventrikuler pacing 'in rolu.
Myotonic dystrophy type 1 (MD1) has been identified as an autosomal dominant disorder associated with the presence of an abnormal expression of a cytosine-thymine-guanine trinucleotide repeat on chromosome 19ql3.3. The classical symptoms are myotonia, muscle atrophy, cataract and a characteristic facial appearance (1, 2). The cardiac involvement, noticed in about 80% of cases, predominantly affects the conduction system, while myocardial contractile function is less commonly impaired in MD1 patients. Heart failure (HF) often occurs late in the course of the disease as consequence of cardiac myopathy due to progressive scar replacement (3). Cardiac resynchronization therapy (CRT) is an innovative new therapy that can relieve HF symptoms by improving the coordination of the heart's contractions.
A 24-year-old man with myotonic dystrophy type 1 was referred to our division for dyspnea and palpitations. On physical examination crackles at the basal fields of lungs were detected. Electrocardiogram (ECG) revealed sinus rhythm, normal axis, prolonged PR interval and complete left bundle-branch block (LBBB) with QRS duration of 160 ms. Transthoracic echocar-diography showed dilated cardiomyopathy with evident left systolic dysfunction and overt intraventricular and interventricular dyssynchrony. In particular, left ventricular (LV) ejection fraction (EF) was 20%, as calculated by both the Simpson's biplane method and by 3D echocardiography, and significant intraventricular mechanical dyssynchrony was documented by both tissue Doppler and by 3D echocardiography (Fig. 1). At admission, the patient was taking angiotensin converting enzyme inhibitor and coenzyme Q10. The electrophysiological study showed a baseline prolonged AH (147 ms) and HV interval (75 ms); the programmed ventricular stimulation, using up to triple extrastimuli, revealed a sustained right bundle ventricular tachycardia (VT) with right inferior axis and cycle length of 290 ms, treated by external DC shock. According to the characteristic findings of overt ventricular dyssynchrony, complete LBBB, inducible VT, a biventricular implantable cardioverter-defibrillator (ICD) was implanted. At one month follow up, we performed the echocardiographic optimization of the atrioventricular and interventricular intervals during cardiac resyn-chronization. At six months follow-up the patient experienced symptom relief; ECG revealed paced ventricular rhythm with narrow QRS complexes; Echocardiogram showed increased ejection fraction and LV stroke volume, while LV mechanical dyssynchrony was significantly reduced (Fig. 2, 3). Six months later ambulatory interrogation of device revealed one proper and effective ICD shock, occurring during an episode of ventricular tachycardia (Fig. 4).
Heart failure is rare in myotonic dystrophy type 1 and often occurs late in the course of the disease. The clinical recognition of heart failure in muscular disease is more difficult than in patients with a normal muscular function as fatigue is inherent to the muscular weakness and exercise tolerance is already impaired by the muscular disease itself. According to ESC 2007 Guidelines for Cardiac Pacing (4), there is neither a clear consensus about biventricular pacing nor the usage of implantable cardiac defibrillator for patients with overt myotonic heart disease. Basing on progressive deterioration of the left ventricular function, progression of atrioventricular conduction disturbances and on the occurrence of ventricular tachyarrhythmia, Said et al. (5) hypothesized a role for biventricular ICD in MD1 patients who necessitated permanent pacemaker implantation. Kilic et al. (6) described the first case of efficacy cardiac resynchronization therapy in MD1 patient with heart failure and complete LBBB with ventricular asynchrony; the intra-cardiac defibrillator implantation was not performed because of no induced serious life threatening ventricular arrhythmia in the EPS.
[FIGURE 1 OMITTED]
[FIGURE 2 OMITTED]
[FIGURE 3 OMITTED]
[FIGURE 4 OMITTED]
In our patient, the early onset heart failure may be related to the electromechanical delay caused by both intra- and interventricular asynchrony. ICD-CRT can be a useful therapy in MD1 presenting with heart failure, cardiac dilatation with low EF, complete LBBB and induc-ible ventricular tachyarrhythmias. The spontaneous ventricular tachycardia, occurred in our patient at twelve months follow up, suggests that the improvement in ejection fraction may not reduce the arrhythmic risk in MD1 patients.
In MD1 patients with early onset heart failure and complete LBBB, ICD-CRT implantation may improve "electrical" left ventricular dysfunction; induce reverse remodelling and relief in symptoms of heart failure. ICD-CRT implantation may be a life-saving treatment modality especially in high-risk MD1 patient with inducible malignant ventricular arrhythmias. The improvement in ejection fraction does not seem reduce the arrhythmic risk in MD1 patients. The early deterioration of the left ventricular function related to left bundle-branch dyssynchrony and the occurrence of ventricular tachyarrhythmia poses the question whether a biventricular ICD should be the first choice management in MD1 with early onset heart failure and complete LBBB.
(1.) Pelargonio G, Dello Russo A, Sanna T, De Martino G, Bellocci F Myotonic dystrophy and the heart. Heart 2002; 88: 665-70. [CrossRef]
(2.) De Ambroggi L, Raisaro A, Marchiano V, Radice S, Meola G. Cardiac involvement in patients with myotonic dystrophy: characteristic features of magnetic resonance imaging. Eur Heart J 1995; 16: 1007-10.
(3.) Tokgozoglu LS, Ashizawa T, Pacifico A, Armstrong RM, Epstein HF Zoghbi WA. Cardiac involvement in a large kindred with myotonic dystrophy. Quantitative assessment and relation to size of CTG repeat expansion. JAMA 1995; 274: 813-9. [CrossRef]
(4.) Vardas PE, Auricchio A, Blanc JJ, Daubert JC, Drexler H, Ector H, et al. European Society of Cardiology; European Heart Rhythm Association. Guidelines for cardiac pacing and cardiac resynchronization therapy: The Task Force for Cardiac Pacing and Cardiac Resynchronization Therapy of the European Society of Cardiology. Developed in collaboration with the European Heart Rhythm Association. Eur Heart J 2007; 28: 2256-95.
(5.) Said SAM, Baart JC, de Voogt WG. Pacing for conduction disturbances in Steinert's disease: a new indication for biventricular ICD? Neth Heart J 2006; 14: 258-62.
(6.) Kilic T, Vural A, Ural D, Sahin T, Agacdiken A, Ertas G, et al. Cardiac resyn-chronization therapy in a case of myotonic dystrophy (Steinert's disease) and dilated cardiomyopathy. Pacing Clin Electrophysiol 2007; 30: 916-20
Vincenzo Russo, Anna Rago, Antonello D'Andrea, Luisa Politano *, Gerardo Nigro
Department of Cardiology, * Cardiomyology and Genetic Section, Department of Internal and Experimental Medicine, Second University of Naples, Naples-Italy
Address for Correspondence/Yazisma Adresi: Vincenzo Russo, MD Second University of Naples, Chair of Cardiology, Naples-Italya Phone:0039 0817062355 E-mail: firstname.lastname@example.org
Available Online Date/Cevrimici Yayin Tarihi: 22.06.2012
|Printer friendly Cite/link Email Feedback|
|Title Annotation:||Case Reports/Olgu Sunumlari|
|Author:||Russo, Vincenzo; Rago, Anna; D'Andrea, Antonello; Politano, Luisa; Nigro, Gerardo|
|Publication:||The Anatolian Journal of Cardiology (Anadolu Kardiyoloji Dergisi)|
|Date:||Sep 1, 2012|
|Previous Article:||Relationship between acute atrial fibrillation attack and intensive cigarette smoking/Yogun sigara kullanimi ve akut atriyal fibrilasyon atagi...|
|Next Article:||Successful catheter ablation of symptomatic premature ventricular contractions originating from mitral annulus/Mitral anulusten kaynaklanan...|