Images in Cardiovascular Medicine

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1 Images in Cardiovascular Medicine Right Ventricular Hypertrophy Along With Malignant Ventricular Arrhythmias An Uncommon Case of Sarcoidosis at Cardiac Magnetic Resonance Imaging Matthias Barral, MD; Estelle Gandjbakhch, MD, PhD; Jean-Pierre Fouret, MD, PhD; Fleur Cohen Aubart, MD, PhD; Arnaud Flores, MD; Nicolas Badenco, MD; Philippe Cluzel, MD, PhD; Alban Redheuil, MD, PhD 51-year-old black man without a personal or family history of cardiovascular disease was admitted to our hos- A pital following syncope. Of note, he reported several episodes of chest pain and palpitations with lipothymia in the past few years associated with progressive dyspnea reaching New York Heart Association class II. ECG showed negative T waves in the precordium (V3 through V4) without significant ST deviation, monomorphic ventricular ectopies of septal origin with bursts of rapid polymorphic ventricular tachycardia, and mild first-degree atrioventricular (AV) block (Figure 1). Clinical examination and chest radiography were normal. Laboratory tests showed mildly elevated ultrasensitive troponin at 36 ng/ml, normal blood cell count, and C-reactive protein. Transthoracic echocardiography found interventricular septal hypertrophy (25 mm) without left ventricular (LV) dilatation or regional wall motion abnormality and no pericardial effusion, and the diagnosis of hypertrophic cardiomyopathy was suspected at the first step. β-blocker therapy was initiated and the patient was monitored showing severe lengthening of the PR interval (Figure 1). Cardiac MRI found atypical and severe concentric right ventricular (RV) hypertrophy with diffuse elevation of myocardial signal on T2-weighted short tau inversion recovery images (Figure 2 Movies I and II in the online-only Data Supplement), and severe RV free wall hypokinesia along with global asynchrony of RV contraction. The LV ejection fraction was confirmed normal, whereas the RV ejection fraction was markedly impaired at 35%. First-pass perfusion of the RV myocardium was slightly delayed in comparison with the LV. There was an intense and diffuse delayed enhancement of RV myocardium predominant in the right side of the septal wall but no LV delayed enhancement (Figure 2). Coronary angiography revealed no coronary artery disease. A dual-chamber cardiac defibrillator was implanted. During the follow-up, the patient was admitted with electrical storm with recurrent polymorphic sustained ventricular tachycardia at 220 beats/min triggered by septal ventricular ectopies needing several appropriate implantable cardioverter-defibrillator discharges, despite that the patient was on β-blockers and amiodarone therapy. Radiofrequency ablation was performed after electrophysiological mapping of both ventricles with a primary success confirming the septal origin of ventricular arrhythmias (Figure 3). However, the condition of the patient secondarily worsened with the recurrence of ventricular tachycardia, state III New York Heart Association dyspnea, and apparition of a second-degree Mobitz 1 AV block when echocardiography revealed the reduction of LV ejection fraction at 35%. Endomyocardial biopsy from the septum was then performed revealing gigantocellular inflammatory granulomas without caseum among dystrophic cardiomyocytes (Figure 4). Computed tomography of the chest demonstrated diffuse lymphatic micronodules combined with mediastinal and right gastric lymph node hypertrophy, consistent with lung and lymph node sarcoidosis (Figure 5). The patient received daily intravenous corticosteroids followed by oral steroids at 0.7 mg kg 1 d 1 and intravenous cyclophosphamide. Follow-up was clinically satisfactory, with complete LV ejection fraction recovery at echocardiography, disappearance of ventricular tachycardia, and partial conduction recovery with first-degree AV block along with a significant decrease in the total interventricular septum thickness (Figures 6 and 7 Movies III, IV, and V in the online-only Data Supplement). Although cardiac involvement in sarcoidosis may be found in up to 40% of autopsic series, only 5% of patients presented with inaugural myocarditis in the pre-mri era. 1 Cardiac MRI has been considered as the best imaging modality for the diagnosis of acute myocarditis with sensitivity up to 100% and a From Sorbonne Universités, Université Pierre et Marie Curie, UPMC, Paris VI, Paris, France (M.B., J.-P.F., F.C.A., P.C., A.R.); Cardiovascular and Interventional Radiology Department, Assistance Publique Hôpitaux de Paris (AP-HP), Pitié-Salpêtrière Hospital, Paris, France (M.B., A.F., P.C., A.R.); Rythmology Department, Assistance Publique Hôpitaux de Paris (AP-HP), Pitié-Salpêtrière Hospital, Paris, France (E.G., N.B.); Pathology Department, Assistance Publique Hôpitaux de Paris (AP-HP), Pitié-Salpêtrière Hospital, Paris, France (J.-P.F.); Internal Medicine Department, Assistance Publique Hôpitaux de Paris (AP-HP), Pitié-Salpêtrière Hospital, Paris, France (F.C.A., A.R.); and Institute of Cardiometabolism And Nutrition, Assistance Publique Hôpitaux de Paris (AP-HP), Pitié-Salpêtrière Hospital, Paris, France (A.R.). The online-only Data Supplement is available with this article at /-/DC1. Correspondence to Matthias Barral, MD, Hôpital Pitié-Salpêtrière, Service de Radiologie cardiovasculaire et interventionnel, boulevard de l Hôpital 75013, Paris, France. matthias_barral@yahoo.fr (Circulation. 2015;132:e170-e175. DOI: /CIRCULATIONAHA ) 2015 American Heart Association, Inc. Circulation is available at DOI: /CIRCULATIONAHA e170

2 Barral et al An Uncommon Case of Sarcoidosis in Cardiac MRI e171 specificity of 78%. 2 Indeed, cardiac MRI is able to demonstrate subepicardial or transmural edema, necrosis, microvascular obstruction, and fibrosis in addition to highly accurate biventricular functional evaluation. However, such markers of tissue damage remain nonspecific with regard to etiology, and differential diagnoses such as sarcoidosis, which require a specific treatment, have to be considered. Formal diagnosis of cardiac sarcoidosis remains based on histopathologic proof of noncaseating granuloma that may be found in peripheral or cardiac tissue. 2 Septal involvement in cardiac myocarditis is severe and may lead to a high mortality rate of 60% in the absence of treatment mainly owing to high-grade AV block and ventricular tachycardia or fibrillation. 1 Implantable cardioverter-defibrillator placement along with medical treatment should be considered as soon as possible in the presence of ventricular arrhythmias even in the absence of severely altered LV ejection fraction. Isolated and diffuse RV involvement in sarcoid myocarditis, such as described here, is an uncommon finding. Patchy RV delayed gadolinium myocardial enhancement may be seen in cardiac sarcoidosis, usually associated with LV involvement, 2 and is thought to be a predictor of an adverse prognosis. The presentation here is highly atypical, both in its imaging and rhythmic components with the combination of severe ventricular arrhythmia and aggravating conduction anomalies arising from the septum. Cardiac sarcoidosis presenting as severe RV myocardial hypertrophy is exceptional and has not been reported so far. RV hypertrophic cardiomyopathy could have been discussed as a potential alternative diagnosis according to the echocardiographic findings, but would have been highly unlikely without LV involvement at MRI. Both entities may present in MRI with concentric thickening of the myocardium associated with patchy late enhancement along with edema and may be associated with AV block. However, isolated RV hypertrophic cardiomyopathy is uncommon in hypertrophic cardiomyopathy and is essentially limited to focal hypertrophy and late enhancement of right-left ventricular junctions and associated to LV involvement. 3,4 In conclusion, isolated RV concentric hypertrophy is an uncommon finding in cardiac MRI and, especially when associated with signs of edema and necrosis and combined with severe AV conduction and ventricular arrhythmia, should be considered as a potential cardiac sarcoidosis. None. Disclosures References 1. Mehta D, Lubitz SA, Frankel Z, Wisnivesky JP, Einstein AJ, Goldman M, Machac J, Teirstein A. Cardiac involvement in patients with sarcoidosis: diagnostic and prognostic value of outpatient testing. Chest. 2008;133: doi: /chest Valeyre D, Prasse A, Nunes H, Uzunhan Y, Brillet PY, Müller- Quernheim J. Sarcoidosis. Lancet. 2014;383: doi: / S (13) Maron MS, Hauser TH, Dubrow E, Horst TA, Kissinger KV, Udelson JE, Manning WJ. Right ventricular involvement in hypertrophic cardiomyopathy. Am J Cardiol. 2007;100: doi: /j. amjcard Hansen MW, Merchant N. MRI of hypertrophic cardiomyopathy: part I, MRI appearances. AJR Am J Roentgenol. 2007;189: doi: /AJR

3 e172 Circulation October 6, 2015 Figure 1. A, ECG on admission showing negative T waves in the precordium (V3 to V4) without significant ST deviation, polymorphic narrow ventricular ectopies, and mild first-degree atrioventricular block. After β-blocker therapy was initiated, the patient was monitored showing a lengthening or PR interval. B, The patient received corticosteroid treatment with complete LV ejection fraction recovery at 3 months and partial conduction recovery with grade I AV block. AV indicates atrioventricular; and LV, left ventricular. Figure 2. Cardiac magnetic resonance (CMR) images: severe asymmetrical right ventricular (RV) hypertrophy with marked predominance of wall thickening in the mediobasal region of the interventricular septum (white star) and in the RV free wall (white arrow) in 4-chamber view steady-state free precession cine (A) and short-axis proton density image (B). Interventricular septum (white star) and RV free wall (white arrow) show intramyocardial ill-defined high signal intensity area in short-axis T2-weighted spectral adiabatic inversion recovery image (C). Postgadolinium short-axis steady-state free precession cine image shows marked RV free wall thickening (white arrow) with a intramyocardial ill-defined high signal intensity area within the interventricular septum (white star; D). Four-chamber and short-axis inversion recovery images acquired 10 minutes after gadolinium show marked delayed enhancement of the interventricular septum (white star) and RV free wall (white arrow; E-F).

4 Barral et al An Uncommon Case of Sarcoidosis in Cardiac MRI e173 Figure 3. Radiofrequency ablation of ventricular arrhythmias. The patient developed an electrical storm with polymorphic ventricular tachycardia triggered by narrow ventricular ectopies (*) of septal origin (A). The endocardial mapping of both ventricles was performed with the Velocity system (SJM) and showed a large scarring zone (yellow-red) at the right side of the interventricular septum (IVS) and limited zones of scar (yellow-red) at the left side (voltage map, B). Mapping of the ventricular ectopies localized them in the IVS (activation map, C) within the Purkinje system as demonstrated with the sharp Purkinje potential observed at the beginning of the electrogram (C, arrow). Radiofrequency applications (brown and red points) were performed on both sides of the IVS with progressive disappearance of the ectopies. LV indicates left ventricle; and RV, right ventricle. Figure 4. Histological analysis ( 20; A) and ( 40; B) showed intramyocardial gigantocellular inflammatory granulomas (white arrow) without caseum among dystrophic cardiomyocytes (white star).

5 e174 Circulation October 6, 2015 Figure 5. A, Chest radiography was normal. In particular, there were no signs of hilar lymphadenopathy, interstitial lung disease, or fibrosis. B, Chest computed tomography in the axial plane shows mediastinal lymphadenopathy (black arrow) and pulmonary micronodules located in the peribronchovascular area and along the pleural surface (white arrows). C, Abdominal computed tomography in the axial plane shows gastric lymphadenopathy (white arrow). Figure 6. Echocardiography before and 6 months after beginning of treatment. A and D, Long-axis parasternal view. B and E, Short-axis parasternal view, pillar level. C and F, Short-axis parasternal, mitral valve level. We observed a significant decrease in the total interventricular septum thickness from 23.5 to 27 mm to 16 to 17 mm with an important decrease in the right ventricular septum thickness from 11 mm to 4 mm (long-axis parasternal view; A and D).

6 Barral et al An Uncommon Case of Sarcoidosis in Cardiac MRI e175 Figure 7. Cardiac ECG-gated computed tomography 6 months after beginning of treatment. A through C, Short-axis view, pillar level. D, Four cavities view. We observed a significant decrease in the total interventricular septum thickness from 25 mm to 13 to 15 mm with an important decrease in the right ventricular septum thickness. White arrows show the implantable cardioverter-defibrillator probes in the right ventricle. E and F, Maximumintensity projection in the coronal axis shows vanishing of lymphatic pulmonary micronodules in the left apical lobe (white arrows).