ABC | Volume 110, Nº2, February 2018

Anatomopathological Correlation Case 1/2018 - Young Male with Heart Disease Expressed Mainly as Ventricular Arrhythmia, Right Ventricular Dysfunction and Syncope Desiderio Favarato e Luiz Alberto Benvenuti Instituto do Coração (InCor) HC-FMUSP, São Paulo, SP – Brazil Mailing Address: Vera Demarchi Aiello • Avenida Dr. Enéas de Carvalho Aguiar, 44, subsolo, bloco I, Cerqueira César. Postal Code 05403-000, São Paulo, SP – Brazil E-mail: demarchi@cardiol.br , vera.aiello@incor.usp.br Keywords Arrhythmias, Cardiac; Ventricular Dysfunction, Right; Syncope; Diagnostic Imaging; Defibrillators, Implantable; Catheter Ablation; Heart Transplantation. Section editor: Alfredo José Mansur (ajmansur@incor.usp.br ) Associated editors: Desidério Favarato (dclfavarato@incor.usp.br ) Vera Dermarchi Aiello (anpvera@incor.usp.br ) DOI: 10.5935/abc.20180031 The patient is a 36-year-old male with history of syncope since the age of 20 years and dyspnea since the age of 30 years. He reported marked worsening of those symptoms in the preceding 6 months from the last admission. His symptoms began with episodes of syncope at the age of 20 years. On the investigation, a neurological cause was ruled out, and heart disease with cardiac dilatation and systolic dysfunction of the left ventricle was detected. The patient denied dyspnea at that time. On ECG (2001), low-voltage complexes in the frontal plane and final conduction delay were observed. The laboratory tests (April 2001) revealed: hemoglobin, 14.6 g/dL; hematocrit, 42%; leukocytes, 4900/mm³ (31% neutrophils, 14% eosinophils, 1% basophils, 37% lymphocytes and 17% monocytes); platelets, 170000/mm³; potassium, 4 mEq/L; sodium, 134 mEq/L; creatinine, 1 mg/dL; urea, 39 mg/dL; PT(INR), 1.0; aPTT (rel. times), 1.16. Magnetic resonance angiography (April 12, 2001) of the internal carotid, anterior, middle and posterior cerebral and vertebral arteries was normal. The echocardiogram (June 5, 2001) revealed the following: diameters of the aorta and left atrium, 32 mm, and of the left ventricle (diastolic/systolic), 65/52 mm; ejection fraction (Simpson), 40%; septal and posterior wall thickness, 10 mm; right ventricle, 23 mm. In addition, there were indirect signs of pulmonary hypertension, estimated as 40 mmHg. The left ventricle showed diffuse hypokinesia, and there was marked calcification of the mitral valve leaflets. The exercise test (July 2, 2001) up to 70% of the predicted maximal heart rate showed no change suggestive of ischemia. The blood pressure curve had a depressed pattern. Isolated and paired ventricular extrasystoles were frequent, as were short‑duration nonsustained ventricular tachycardia episodes. The test was interrupted because of exhaustion. The management consisted in heart failure treatment and cardioverter defibrillator implantation, the cardiac findings being attributed to sequelae of myocarditis. His daily prescription was as follows: losartan 50mg, amiodarone 400mg, spironolactone 25 mg, and metoprolol succinate 75 mg. His laboratory tests (Dec 2002) showed: cholesterol, 167 mg/dL; TSH, 6.8 µg/mL; free T4, 1.6 ng/mL; triglycerides, 43 mg/dL; glycemia, 90 mg/dL; uric acid, 4.3 mg/dL. His new echocardiogram (March 2004) revealed the following diameters: aorta, 31 mm; left atrium, 34 mm; left ventricle (diastolic/systolic), 60/50 mm. His ejection fraction was 42%, and the septal and posterior wall thickness, 7 mm. The left ventricle was dilated and diffusely hypokinetic. The right ventricle was 31‑mmthick, dilatedandhypokinetic. The right atriumwas dilated. Pacemaker electrodes were identified in the right chambers. Neither atrioventricular nor ventriculo-arterial valves had changes. The patient developed dyspnea on maximal exertion, but no syncope. There was an episode of inappropriate shock from the cardioverter defibrillator in 2005, due to problems in the ventricular electrode, which was replaced. The disease course was uneventful until 2012. Cardiopulmonary exercise test showed variation of heart rate from 57 bpm to 122 bpm, and of blood pressure from 120/80 mm Hg to 185/70 mm Hg, and maximal oxygen consumption of 28.4 mL/kg/min. During that time, the echocardiography showed ejection fraction ranging from44% (2001) to 39% in 2006, and of 28% in 2011, while the diastolic diameter of the left ventricle remained constant (65 mm in 2001, 66 mm in 2006 and 2011). The patient was referred for surgical treatment assessment for heart failure, but, because he had few symptoms and good physical capacity, clinical and pharmacologic management was maintained (2012). Computed tomographic angiography of the coronary arteries (February 5, 2014) showed neither calcifications nor obstructive lesions. In February 2014, the cardioverter defibrillator delivered a shock, and the patient underwent radiofrequency ablation of the arrhythmia. During the electrophysiological study (February 3, 2014), atrial stimulation triggered atrial fibrillation, which organized as flutter arising from the cavotricuspid isthmus, which was blocked. On the electrical mapping of the right ventricle, areas of scar and low-voltage late potentials were observed in the basal posterior and lateral walls, and radiofrequency pulses were applied, eliminating them. During left ventricular epicardial mapping, a non-dense scar area was identified in the basal portion of the posterolateral wall, as were late potentials. No radiofrequency pulse was applied to those sites. 195