Maurizio Pieroni

Immunosuppressive Therapy for Active Lymphocytic Myocarditis Virological and Immunologic Profile of Responders Versus Nonresponders

Background—The beneficial effect of immunosuppressive treatment on myocarditis is still controversial, possibly because the immunologic and virological profile of potential candidates is largely unknown. Methods and Results—Out of 652 biopsied patients, 112 had a histological diagnosis of active lymphocytic myocarditis; 41 of these 112 patients were characterized by progressive heart failure despite conventional therapy and were treated with prednisone and azathioprine for 6 months. All were resubmitted to cardiac catheterization, angiography, and endomyocardial biopsy at 1 and 6 months and followed-up for 1 year. A total of 21 patients responded with prompt improvement in left ventricular ejection fraction from 25.7±4.1% to 47.1±4.4% and showed evidence of healed myocarditis at control biopsy. Conversely, 20 patients failed to respond and showed a histological evolution toward dilated cardiomyopathy: 12 remained stationary, 3 underwent cardiac transplantation, and 5 died. We retrospectively performed a polymerase chain reaction on frozen endomyocardial tissue for the most common cardiotropic viruses and assessed circulating serum cardiac autoantibodies. Viral genomes were present in biopsy specimens of 17 nonresponders (85%), including enterovirus (n=5), Epstein-Barr virus (n=5) adenovirus (n=4), both adenovirus and enterovirus (n=1), influenza A virus (n=1), parvovirus-B19 (n=1), and in 3 responders, who were all positive for hepatitis C virus. Cardiac autoantibodies were present in 19 responders (90%) and in none of the nonresponders. Conclusions—In patients with active lymphocytic myocarditis, those with circulating cardiac autoantibodies and no viral genome in the myocardium are the most likely to benefit from immunosuppression. The beneficial effect of immunosuppression in hepatitis C virus myocarditis suggests a relevant immunomediated component of damage.

Cardiac histological substrate in patients with clinical phenotype of Brugada syndrome.

Background— The role of structural heart disease and sodium channel dysfunction in the induction of electrical instability in Brugada syndrome is still debated. Methods and Results— We studied 18 consecutive patients (15 males, 3 females; mean age 42.0±12.4 years) with clinical phenotype of Brugada syndrome and normal cardiac structure and function on noninvasive examinations. Clinical presentation was ventricular fibrillation in 7 patients, sustained polymorphic ventricular tachycardia in 7, and syncope in 4. All patients underwent cardiac catheterization, coronary and ventricular angiography, biventricular endomyocardial biopsy, and DNA screening of the SCN5A gene. Biopsy samples were processed for histology, electron microscopy, and molecular screening for viral genomes. Microaneurysms were detected in the right ventricle in 7 patients and also in the left ventricle in 4 of them. Histology showed a prevalent or localized right ventricular myocarditis in 14 patients, with detectable viral genomes in 4; right ventricular cardiomyopathy in 1 patient; and cardiomyopathic changes in 3. Genetic studies identified 4 carriers of SCN5A gene mutations that cause in vitro abnormal function of mutant proteins. In these patients, myocyte cytoplasm degeneration was present at histology, whereas terminal dUTP nick end-labeling assay showed a significant increase of apoptotic myocytes in right and left ventricle versus normal controls (P=0.014 and P=0.013, respectively). Conclusions— Despite an apparently normal heart at noninvasive evaluation, endomyocardial biopsy detected structural alterations in all 18 patients with Brugada syndrome. Mutations in the SCN5A gene, identified in 4 of the 18 patients, may have induced concealed structural abnormalities of myocardiocytes that accounted for paroxysmal arrhythmic manifestations.

Early Detection of Fabry Cardiomyopathy by Tissue Doppler Imaging

Background—Fabry cardiomyopathy is diagnosed by detection of left ventricular hypertrophy (LVH) in patients with &agr;-Galactosidase A deficiency. Conventional noninvasive tools are unable to provide a preclinical diagnosis allowing prompt institution of enzymatic therapy. Methods and Results—We studied three groups of patients: 10 patients with causal mutations for Fabry disease and LVH, 10 mutation-positive patients without LV, and 10 healthy relatives without causal mutations and no LVH. All patients with LVH and 6 patients with Fabry disease without LVH with complex repetitive ventricular arrhythmias underwent biventricular endomyocardial biopsy to assess cardiac involvement. In all patients 2-dimensional echocardiography with tissue Doppler analysis in the pulsed Doppler mode was performed: systolic (Sa), early diastolic (Ea), and late diastolic (Aa) velocities were measured, and the Ea/Aa ratio and the dimensionless parameter E/Ea were computed at both corners of the mitral annulus. Histology and electron microscopy studies showed glycosphingolipid deposits in all cases. All mutation-positive patients had significant reduction of Sa, Ea, and Aa velocities at both corners of the mitral annulus compared with normal control subjects. Ea/Aa ratio was significantly lower and E/Ea ratio significantly higher in mutation-positive patients than in control subjects. Patients with LVH showed significantly lower contraction and relaxation tissue Doppler velocities, lower Ea/Aa ratio, and higher E/Ea ratio in comparison with mutation-positive patients with no LVH. Conclusions—Fabry cardiomyopathy is characterized by reduced myocardial contraction and relaxation tissue Doppler velocities, detectable even before development of LVH. Tissue Doppler imaging can provide a preclinical diagnosis of Fabry cardiomyopathy, allowing early institution of enzyme replacement therapy.

Prevalence of Fabry Disease in Female Patients With Late-Onset Hypertrophic Cardiomyopathy

Background—Fabry disease (FD) has been recognized as the cause of left ventricular hypertrophy in 6% of men with late-onset hypertrophic cardiomyopathy (HCM). Although FD is considered a recessive X-linked disorder, affected women are increasingly reported. The aim of our study was to determine the prevalence of FD in female patients with HCM. Methods and Results—Thirty-four consecutive women (mean age, 50±13.6 years) who received an ECG and echocardiographic diagnosis of HCM were submitted to an invasive cardiac study that included a biventricular endomyocardial biopsy. Tissue samples were analyzed for histology and electron microscopy. Peripheral blood activity of &agr;-galactosidase (&agr;-Gal) A was assessed in all patients. None of them had a family history of FD. Histology and electron microscopy showed in 4 patients (12%; mean age, 51.5±3.9 years) the presence of cell vacuoles characterized by the accumulation of glycolipid material organized in concentric lamellar structures, diagnostic for FD. In the remaining patients, histology was consistent with HCM. In all the female carriers, the heart was the only organ clinically involved in the disease, showing concentric hypertrophy in 2 patients, asymmetric hypertrophy in 1, and apical hypertrophy in 1. The &agr;-Gal A enzymatic activity was 44±14% of control values. Genetic analysis showed the presence of &agr;-Gal A gene mutation in all 4 cases. Conclusions—FD may account for up to 12% of females with late-onset HCM. Those heterozygous for FD with left ventricular hypertrophy are potential candidates for enzyme enhancement/replacement therapy.

Celiac Disease Associated With Autoimmune Myocarditis

Background—Both celiac disease (CD) and myocarditis can be associated with systemic autoimmune disorders; however, the coexistence of the 2 entities has never been investigated, although its identification may have a clinical impact. Methods and Results—We screened the serum of 187 consecutive patients with myocarditis (118 males and 69 females, mean age 41.7±14.3 years) for the presence of cardiac autoantibodies, anti–tissue transglutaminase (IgA-tTG), and anti-endomysial antibodies (AEAs). IgA-tTG–positive and AEA-positive patients underwent duodenal endoscopy and biopsy and HLA analysis. Thirteen of the 187 patients were positive for IgA-tTG, and 9 (4.4%) of them were positive for AEA. These 9 patients had iron-deficient anemia and exhibited duodenal endoscopic and histological evidence of CD. CD was observed in 1 (0.3%) of 306 normal controls (P <0.003). In CD patients, myocarditis was associated with heart failure in 5 patients and with ventricular arrhythmias (Lown class III-IVa) in 4 patients. From histological examination, a lymphocytic infiltrate was determined to be present in 8 patients, and giant cell myocarditis was found in 1 patient; circulating cardiac autoantibodies were positive and myocardial viral genomes were negative in all patients. HLA of the patients with CD and myocarditis was DQ2-DR3 in 8 patients and DQ2-DR5(11)/DR7 in 1 patient. The 5 patients with myocarditis and heart failure received immunosuppression and a gluten-free diet, which elicited recovery of cardiac volumes and function. The 4 patients with arrhythmia, after being put on a gluten-free diet alone, showed improvement in the arrhythmia (Lown class I). Conclusions—A common autoimmune process toward antigenic components of the myocardium and small bowel can be found in >4% of the patients with myocarditis. In these patients, immunosuppression and a gluten-free diet can be effective therapeutic options.

Smooth muscle cells in human atherosclerotic plaques secrete and proliferate in response to high mobility group box 1 protein

High mobility group box 1 protein (HMGB1) is a chromatin component leaked out by necrotic cells and actively secreted by activated myeloid cells. The extracellular protein is a potent mediator of tissue remodeling. We show here that human athero‐ sclerotic plaques, but not normal arteries, produce extracellular HMGB1. Secreted HMGB1 originates from endothelial cells, by neointimal foam cells, and also smooth muscle cells (SMCs). SMCs are an unex‐ pected source for secreted HMGB1, since they nor‐ mally express much lower amounts of HMGB1 than other cells types, and they do not secrete it. However, cultured SMCs actively secrete HMGB1 after choles‐ terol loading. In turn, in response to HMGB1, SMCs proliferate, migrate, and secrete more HMGB1. Thus, SMCs are both a source and a target of HMGB1; blocking HMGB1 secretion by SMCs can be an impor‐ tant strategy for treatment of atherosclerotic disease and in particular restenosis.—Porto, A., Palumbo, R., Pieroni, M., Aprigliano, G., Chiesa, R., Sanvito, F., Maseri, A., Bianchi, M. E. Smooth muscle cells in human atherosclerotic plaques secrete and proliferate in response to high mobility protein box 1. FASEB J. 20, E1955–E1963 (2006)

High Prevalence of Myocarditis Mimicking Arrhythmogenic Right Ventricular Cardiomyopathy Differential Diagnosis by Electroanatomic Mapping-Guided Endomyocardial Biopsy

OBJECTIVES We evaluated the diagnostic contribution and the therapeutic and prognostic implications of 3-dimensional electroanatomic mapping (EAM)-guided endomyocardial biopsy (EMB) in patients with arrhythmogenic right ventricular cardiomyopathy (ARVC). BACKGROUND ARVC is a frequent cause of life-threatening ventricular arrhythmias and sudden death in young people. The value of current diagnostic criteria and the role of imaging techniques and EMB are still debated. METHODS We studied 30 consecutive patients (17 male, mean age 43 +/- 17 years) with a noninvasive diagnosis of ARVC according to current criteria. All patients underwent 3-dimensional EAM-guided EMB. RESULTS Twenty-nine (97%) of 30 patients presented an abnormal voltage map. Histology and immunohistochemistry confirmed the diagnosis of ARVC in 15 patients, and showed active myocarditis according to Dallas criteria in the remaining 15 patients. Patients with ARVC were not distinguishable on the basis of clinical features, presence, and severity of structural and functional right ventricular abnormalities and 3-dimensional EAM findings. On the basis of clinical and histological features, a cardioverter-defibrillator was implanted in 13 patients with biopsy-proven ARVC and in 1 patient only with myocarditis. At a mean follow-up of 21 +/- 8 months, 7 (47%) patients with ARVC experienced a recurrence of symptomatic sustained ventricular arrhythmias with appropriate defibrillator intervention in all cases. All patients with myocarditis remained asymptomatic and free from arrhythmic events. CONCLUSIONS Right ventricular myocarditis frequently mimics ARVC. Three-dimensional EAM-guided EMB is a safe and effective tool in differential diagnosis and in the selection of the most appropriate therapeutic strategy.

Delayed-enhanced cardiac MRI for differentiation of Fabry's disease from symmetric hypertrophic cardiomyopathy.

OBJECTIVE Fabrys disease may be difficult to differentiate from symmetric hypertrophic cardiomyopathy. Our aim was to compare the myocardial location and distribution patterns of delayed enhancement between patients with Fabrys disease who are affected by symmetric myocardial hypertrophy and patients with symmetric hypertrophic cardiomyopathy in order to identify a specific sign to best differentiate the two diseases. CONCLUSION Patients with Fabrys disease-related hypertrophy showed left ventricular (LV) delayed enhancement with a typical and consistently found pattern characterized by the involvement of the inferolateral basal or mid basal segments and a mesocardial distribution that spared the subendocardium. This pattern seems to be specific to Fabrys disease; in fact, patients with symmetric hypertrophic cardiomyopathy had variable locations and distributions of delayed enhancement. These observations may contribute to identifying Fabrys disease as a specific cause of symmetric hypertrophy.

Overexpression of tumor necrosis factor (TNF)α and TNFα receptor I in human viral myocarditis: clinicopathologic correlations

Proinflammatory cytokines, including tumor necrosis factor (TNF)α, have been recognized as important physiopathogenetic factors in the initiation and continuation of inflammatory cardiomyopathies. Experimental and preliminary human studies have demonstrated that TNFα plays a crucial role in enteroviral-induced myocarditis. In this study, we investigated the expression of TNFα and both its receptors (TNFRI and TNFRII) in both viral and nonviral myocarditis. Myocardial expression of TNFα was then correlated with different clinical and pathologic findings. TNFα expression was investigated in endomyocardial biopsies obtained from 38 patients with myocarditis and from eight control subjects by using reverse transcriptase-polymerase chain reaction (PCR) and immunohistochemistry. Viral etiology was diagnosed by PCR in 20 cases: enterovirus in seven, Epstein–Barr virus in four, hepatitis C virus in three, adenovirus in two, influenza virus in two, cytomegalovirus in one, and double infection adenovirus and enterovirus in one. Immunohistochemistry was also used to analyze both TNFα receptors (RI and RII). A semiquantitative analysis was employed (score 0–3) for necrosis, inflammation, fibrosis and immunohistochemical findings. TNFα mRNA and TNFα protein were significantly more present in viral myocarditis than in nonviral myocarditis (16/20 vs 3/18, P=0.001). Remarkable immunostaining was observed for both receptors, particularly TNFRI. Histological analysis revealed that myocardial necrosis (mean score 1.89 vs 1.15, P=0.01) and cellular infiltration (mean score 2.26 vs 1.78, P=0.05) were more prominent in TNFα-positive cases. Among TNFα-positive cases, the greater TNFα mRNAs, the more impaired was cardiac function. Our findings suggest that the expression of TNFα may play an important role in the pathogenesis of viral myocarditis of any etiology and may influence the severity of cardiac dysfunction. Cytokine effects are more strictly linked to overexpression of TNFRI.

Recognizing and treating myocarditis in recent-onset systemic sclerosis heart disease: Potential utility of immunosuppressive therapy in cardiac damage progression

OBJECTIVES Scleroderma heart disease is a major risk of death in systemic sclerosis (SSc). Mechanisms underlying myocardial damage are still unclear. We performed an extensive study of SSc patients with recent-onset symptoms for heart disease and examined the efficacy of immunosuppressive therapy. METHODS A cohort of 181 SSc patients was enrolled. Of these, 7 patients newly developed clinical symptoms of heart disease (heart failure, chest pain, and palpitation); all of them showed mild but persistent increase in cardiac enzymes. These patients underwent Holter ECG, 2D-echocardiography, perfusional scintigraphy, delayed-enhancement-cardiac magnetic resonance (DE-CMR), coronary angiography, and endomyocardial biopsy. Patients were treated for at least 12 months and followed-up for 5 years. RESULTS Ventricular ectopic beats (VEBs) were found in 4 patients, wall motion abnormalities in 3, pericardial effusion in 6, and DE in CMR in 6 with T2-hyperintensity in 2. In all patients, histology showed upregulation of endothelium adhesion molecules and infiltration of activated T lymphocytes, with (acute/active myocarditis in 6) or without (chronic/borderline myocarditis in 1) myocyte necrosis. Parvovirus B19 genome was detected in 3. None showed occlusion of coronary arteries or microvessels. Compared with SSc controls, these patients more often had early disease, skeletal myositis, c-ANCA/anti-PR3 positivity, VEBs, pericardial effusion, and systolic and/or diastolic dysfunction. Immunosuppressive therapy improved symptoms and led to cardiac enzyme negativization; however, 2 patients died of sudden death during follow-up. CONCLUSIONS Myocarditis is a common finding in SSc patients with recent-onset cardiac involvement. Its early detection allowed to timely start an immunosuppressive treatment, preventing cardiac damage progression in most cases.