Immunosuppressive Therapy Improves Both Short- and Long-Term Prognosis in Patients With Virus-Negative Nonfulminant Inflammatory Cardiomyopathy

Clinical significance of chronic myocarditis: systematic review and meta-analysis

Chronic myocarditis is a prolonged inflammatory condition in the myocardium and its histological manifestation is defined by the presence of an inflammatory infiltrate. Chronic myocarditis has not been well known and its treatment of chronic myocarditis has not been established. Primary outcome of this study was to assess the efficacy of immunomodulatory treatment in addition to conventional treatment, and secondary outcomes were to clarity the prognosis of natural history of chronic myocarditis and incidence of chronic myocarditis in patients with dilated cardiomyopathy (DCM). We searched for studies in Medline, Embase, Cochrane Central Register of Controlled Trials, and Igaku Chuo Zasshi published between January 1946 and June 2020. Sixteen studies met the inclusion criteria. A meta-analysis revealed that patients receiving immunomodulatory treatment showed an improvement in left ventricular ejection fraction after immunomodulatory treatment compared to the control group (hazard ratio, 16.65; confidence interval, 4.55-28.74; p = 0.007). Five-year survival rate of the patients with inflammatory DCM (iDCM) and DCM was 52.7-70.3% and 51.9-91.1%, respectively. Moreover, 51.5%-62.7% of patients with DCM met the criteria of iDCM. Our systematic review revealed that patients with chronic myocarditis had poor prognosis and immunomodulatory treatment was significantly effective in addition to conventional treatment.

Contemporary etiology and prognosis of dilated non-ischemic cardiomyopathy

INTRODUCTION

Non-ischemic dilated cardiomyopathy (NI-DCM) represents a specific etiology of systolic heart failure that usually affect young individuals with a genetic background in up to 40% of cases. Behind the term NI-DCM there is a spectrum of different diseases, and an accurate etiological classification appears pivotal for the clinical management and prognostic stratification of these patients.

EVIDENCE ACQUISITION

In the last years the prognosis of NI-DCM patients dramatically improved thanks to the progresses in medical treatment/ device therapy and earlier diagnosis especially in familial context. In this review we summarize the actual state of art in the management of these patients.

EVIDENCE SYNTHESIS

In the era of precision medicine, a lot of progresses have been made to expand our knowledge on the management of NI-DCM patients. A complex interaction between genotype and external triggers is the main determinant of the clinical phenotype in NI-DCM, and a lot of efforts must be done by clinicians to systematically rule out all the possible causes involved in the pathogenesis. Progresses in cardiac imaging and familial screening led us to detect subtle abnormalities in the initial phase of the disease and also helped us to furtherly stratify the prognosis and arrhythmic risk of these patients. It is plausible that a more precise etiological classification will be needed in the near future.

CONCLUSIONS

NI-DCM contains a spectrum of different diseases. Proper etiological classification, early diagnosis and strict follow-up are essential to tailor care of these patients.

Heart Failure Association of the ESC, Heart Failure Society of America and Japanese Heart Failure Society Position statement on endomyocardial biopsy

Endomyocardial biopsy (EMB) is an invasive procedure, globally most often used for the monitoring of heart transplant (HTx) rejection. In addition, EMB can have an important complementary role to the clinical assessment in establishing the diagnosis of diverse cardiac disorders, including myocarditis, cardiomyopathies, drug-related cardiotoxicity, amyloidosis, other infiltrative and storage disorders, and cardiac tumours. Improvements in EMB equipment and the development of new techniques for the analysis of EMB samples have significantly improved diagnostic precision of EMB. The present document is the result of the Trilateral Cooperation Project between the Heart Failure Association of the European Society of Cardiology, the Heart Failure Society of America, and the Japanese Heart Failure Society. It represents an expert consensus aiming to provide a comprehensive, up-to-date perspective on EMB, with a focus on the following main issues: (i) an overview of the practical approach to EMB, (ii) an update on indications for EMB, (iii) a revised plan for HTx rejection surveillance, (iv) the impact of multimodality imaging on EMB, and (v) the current clinical practice in the worldwide use of EMB.

Heart Failure Association, Heart Failure Society of America, and Japanese Heart Failure Society Position Statement on Endomyocardial Biopsy

Endomyocardial biopsy (EMB) is an invasive procedure, globally most often used for the monitoring of heart transplant rejection. In addition, EMB can have an important complementary role to the clinical assessment in establishing the diagnosis of diverse cardiac disorders, including myocarditis, cardiomyopathies, drug-related cardiotoxicity, amyloidosis, other infiltrative and storage disorders, and cardiac tumors. Improvements in EMB equipment and the development of new techniques for the analysis of EMB samples has significantly improved the diagnostic precision of EMB. The present document is the result of the Trilateral Cooperation Project between the Heart Failure Association of the European Society of Cardiology, Heart Failure Society of America, and the Japanese Heart Failure Society. It represents an expert consensus aiming to provide a comprehensive, up-to-date perspective on EMB, with a focus on the following main issues: (1) an overview of the practical approach to EMB, (2) an update on indications for EMB, (3) a revised plan for heart transplant rejection surveillance, (4) the impact of multimodality imaging on EMB, and (5) the current clinical practice in the worldwide use of EMB.

Effectiveness of myocarditis therapy depending on the diagnosis approach (with or without myocardial biopsy)

Aim. To evaluate the effectiveness of myocarditis therapy depending on the diagnosis approach (with or without myocardial biopsy).

Material and methods. The study included 83 patients ≥18 years old with severe and moderate myocarditis (25 women and 58 men; mean age, 45,7±11,7 years), established by myocardial biopsy (group 1, n=36) or by a non-invasive diagnostic algorithm (group 2, n=47), for which immunosuppressive therapy (IST) was carried out. Inclusion criteria were left ventricular (LV) end-diastolic dimension >5,5 cm and ejection fraction (EF) <50%. An endomyocardial (n=31) or intraoperative (n=5) biopsy with a study of the viral genome and level of anticardiac antibodies were performed. Coronary angiography (29%), cardiac multislice computed tomography (75%), cardiac magnetic resonance imaging (41%), and 99mTc-MIBI scintigraphy (35%) were also carried out. The mean follow-up period was 3 years (36 [12; 65] months). The study was approved by the Intercollegiate Ethics Committee.

Results. The groups were completely comparable in age, baseline parameters (class III [2,25; 3] and III [2; 3] heart failure (HF); end-diastolic LV dimension, 6,7±0,7 and 6,4±0,7 cm; EF, 29,9±8,7 and 31,4±9,3%), the extent of cardiac therapy (excluding the administration rate of в-blockers — 94,4 and 78,7%, p<0,05) and 1ST (methylprednisolone in 91,7 and 89,4% of patients at a mean dose of 24 [16; 32] and 20 [15; 32] mg/day, azathioprine in 50,0 and 46,8% of patients at a mean dose of 150 mg/day or mycophenolate mofetil 2,0 g/day in 30,6% in group 1, hydroxychloroquine 0,2 g/day in 27,8 and 23,4%). Biopsy in group 1 revealed active/borderline (61/39%) myocarditis, in 8 patients — viral genome in the myocardium, including parvovirus B19 in 7 of them. Both groups showed a comparable significant increase in EF after 6 months up to 37,6±8,1 and 42,6±11,5% (p<0,001) and after 27 [12; 54] months up to 43,4±9,6 and 45,5±12,3% (p<0,001), as well as a significant decrease in HF class to 2 [1; 2] in both groups. An increase in EF by ≥10% was recorded in 70 and 72% of patients, respectively. The mortality rate was 13,9 and 12,8%. Taking into account the only transplantation in group 2, the death+transplantation endpoints reached 13,9 and 14,9% of patients (without significant differences between the groups).

Conclusion. In patients with severe and moderate myocarditis diagnosed with and without myocardial biopsy, the effectiveness of combined therapy, including IST, was comparable. If it is impossible to perform a biopsy, complex non-invasive strategy makes it possible to diagnose myocarditis with different probability rate and conduct an effective IST, the refusal of which mostly is not justified.

The Genetic Pathways Underlying Immunotherapy in Dilated Cardiomyopathy

Heart failure (HF) is a global public health threat affecting 26 million individuals worldwide with an estimated prevalence increase of 46% by 2030. One of the main causes of HF and sudden death in children and adult is Dilated Cardiomyopathy (DCM). DCM is characterized by dilation and systolic dysfunction of one or both ventricles. It has an underlying genetic basis or can develop subsequent to various etiologies that cause myocardium inflammation (secondary causes). The morbidity and mortality rates of DCM remains high despite recent advancement to manage the disease. New insights have been dedicated to better understand the pathogenesis of DCM in respect to genetic and inflammatory basis by linking the two entities together. This cognizance in the field of cardiology might have an innovative approach to manage DCM through targeted treatment directed to the causative etiology. The following review summarizes the genetical and inflammatory causes underlying DCM and the pathways of the novel precision-medicine-based immunomodulatory strategies to salvage and prevent the associated heart failure linked to the disease.

The State of the Heart Biopsy: A Clinical Review

Endomyocardial biopsy (EMB) is an invaluable and underused diagnostic tool for myocardial disease. The primary indications are surveillance of cardiac allograft rejection and the diagnosis of inflammatory and infiltrative cardiomyopathies. EMB is typically performed by sampling the right ventricular septum via the right internal jugular vein using fluoroscopic guidance. The diagnostic yield of EMB is improved by sampling both ventricles and with the use of guidance from imaging or electroanatomic mapping. The risk of major cardiac complications is operator dependent and < 1% in experienced centres. EMB is the gold standard and most common form of cardiac allograft rejection surveillance, whereas advanced cardiac imaging and donor-specific antibody quantification provide complementary information. Gene expression profiling is an alternative surveillance strategy to EMB for low-risk patients. EMB is recommended for myocarditis and can guide therapy for giant-cell myocarditis, necrotizing eosinophilic myocarditis, sarcoidosis, and immune checkpoint inhibitor myocarditis. There is growing interest in using EMB to guide therapy for viral myocarditis, although the uptake of this approach is limited to specialized centres. EMB has been replaced as a first-line test for infiltrative cardiomyopathy by nonbiopsy diagnostic techniques, but is still useful to clarify the diagnosis or disease subtype. The miniaturization of bioptomes and advances in laboratory techniques such as microarrays promises to improve the safety and yield of EMB. We review the contemporary use of EMB for cardiac allograft rejection, inflammatory cardiomyopathy, and infiltrative cardiomyopathy.

Efficacy of immunosuppressive therapy in myocarditis: A 30-year systematic review and meta analysis

AIMS

Myocarditis is an inflammation of the heart muscle, due to infectious, toxic or autoimmune causes. Literature reported controversial results in relation to the effect of immunosuppression (IS)/immunomodulation (IM). We aimed at assessing the effect of IS/IM by meta analysis.

METHODS AND RESULTS

Using the P.R.I.S.M.A. approach, two researchers searched for relevant studies on PubMed, Embase, and the Central Registry of Controlled Trials of the Cochrane Library. Proposed MeSH terms were: "immunotherapy OR immune therapy OR immune modeling OR Immunosuppressive Agents" AND "combination OR combined with OR plus" AND "myocarditis OR cardiomyopathies OR inflammatory cardiomyopathy". The language was restricted to English. Reference lists of included articles and those relevant to the topic were hand searched for the identification of additional, potentially relevant articles. The cutoff date was from 1987 until 30th Nov 2019. Reported survival or mortality events or change of left ventricular ejection fraction (LVEF) after IS/IT were primary outcomes of the study; in addition, improvement of New York Heart Association class, follow-up biopsy (Bx) findings, viral genome clearance on Bx and recurrence of myocarditis were recorded if reported. Statistical analysis was conducted using Review Manager 5.3; 5452 studies were screened, of these 73 were assessed for eligibility, including 8 randomized control studies, 26 retrospective studies, 2 prospective studies and 1 case control study, 34 case reports and 2 case series. In prospective studies, the difference in mortality between the IS and control groups tended to be lower in the combined IS groups (12.5% vs. 18.2%) (95% CI of odds ratio 0.7(0.3, 1.64)) and the pooled difference of the increase of LVEF between the IS and control groups tended to be higher in the combined IS groups (95% CI 7.26 (-2.29, 16.81)). In retrospective studies, the difference of survival between the IS and control group was significantly in favor of IS (95%CI Hazard ratio 0.82(0.69, 0.96)).

CONCLUSIONS

A tailored IS may be considered in myocarditis, depending on the phase of the disease, and the type of underlying autoimmune or immune-mediated form.

Myocarditis and inflammatory cardiomyopathy: current evidence and future directions

Inflammatory cardiomyopathy, characterized by inflammatory cell infiltration into the myocardium and a high risk of deteriorating cardiac function, has a heterogeneous aetiology. Inflammatory cardiomyopathy is predominantly mediated by viral infection, but can also be induced by bacterial, protozoal or fungal infections as well as a wide variety of toxic substances and drugs and systemic immune-mediated diseases. Despite extensive research, inflammatory cardiomyopathy complicated by left ventricular dysfunction, heart failure or arrhythmia is associated with a poor prognosis. At present, the reason why some patients recover without residual myocardial injury whereas others develop dilated cardiomyopathy is unclear. The relative roles of the pathogen, host genomics and environmental factors in disease progression and healing are still under discussion, including which viruses are active inducers and which are only bystanders. As a consequence, treatment strategies are not well established. In this Review, we summarize and evaluate the available evidence on the pathogenesis, diagnosis and treatment of myocarditis and inflammatory cardiomyopathy, with a special focus on virus-induced and virus-associated myocarditis. Furthermore, we identify knowledge gaps, appraise the available experimental models and propose future directions for the field. The current knowledge and open questions regarding the cardiovascular effects associated with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection are also discussed. This Review is the result of scientific cooperation of members of the Heart Failure Association of the ESC, the Heart Failure Society of America and the Japanese Heart Failure Society.

Cardiac Inflammation Impedes Response to Cardiac Resynchronization Therapy in Patients With Idiopathic Dilated Cardiomyopathy

BACKGROUND

Cardiac resynchronization therapy (CRT) is an established therapy in patients with dilated cardiomyopathy (DCM) and conduction disorders. Still, one-third of the patients with DCM do not respond to CRT. This study aims to depict the underlying cardiac pathophysiological processes of nonresponse to CRT in patients with DCM using endomyocardial biopsies.

METHODS

Within the Maastricht and Innsbruck registries of patients with DCM, 99 patients underwent endomyocardial biopsies before CRT implantation, with histological quantification of fibrosis and inflammation, where inflammation was defined as >14 infiltrating cells/mm². Echocardiographic left ventricular end-systolic volume reduction ≥15% after 6 months was defined as response to CRT. RNA was isolated from cardiac biopsies of a representative subset of responders and nonresponders.

RESULTS

Sixty-seven patients responded (68%), whereas 32 (32%) did not respond to CRT. Cardiac inflammation before implantation was negatively associated with response to CRT (25% of responders, 47% of nonresponders; odds ratio 0.3 [0.12-0.76]; P=0.01). Endomyocardial biopsies fibrosis did not relate to CRT response. Cardiac inflammation improved the robustness of prediction beyond well-known clinical predictors of CRT response (likelihood ratio test P<0.001). Cardiac transcriptomic profiling of endomyocardial biopsies reveals a strong proinflammatory and profibrotic signature in the hearts of nonresponders compared with responders. In particular, COL1A1, COL1A2, COL3A1, COL5A1, POSTN, CTGF, LOX, TGFβ1, PDGFRA, TNC, BGN, and TSP2 were significantly higher expressed in the hearts of nonresponders.

CONCLUSIONS

Cardiac inflammation along with a transcriptomic profile of high expression of combined proinflammatory and profibrotic genes are associated with a poor response to CRT in patients with DCM.

Immunosuppressive therapy of biopsy proved immune-mediated lymphocytic myocarditis in the virus-negative and virus-positive patients

PURPOSE

to study the effect of immunosupressive therapy (IST) in the virus-negative and virus-positive patients with immune-mediated myocarditis.

METHODS

in 60 patients (45 male, 46.7 ± 11.8 years, mean LV EDD, 6.7 ± 0.7 cm, EF 26.2 ± 9.1%) active/borderline myocarditis was verified by endomyocardial biopsy (n = 38), intraoperative biopsy (n = 10), examination of explanted heart (n = 3) and autopsy (n = 9). Indications for IST determined based on histological, immune activity. The follow-up was 19.0 [7.25; 40.25] months.

RESULTS

The viral genome in the myocardium was detected in 32 patients (V+ group), incl. parvovirus B19 in 23. The anti-heart antibody level was equally high in the V+ and V- patients. Antiviral therapy was administered in 24 patients. IST (in 22 V+ and 24 V- patients) include steroids (n = 40), hydroxychloroquine (n = 20), azathioprine (n = 21). The significant decrease of LV EDD (6.7 ± 0.7 to 6.4 ± 0.8), PAP (48.9 ± 15.5 to 39.4 ± 11.5 mm Hg, р<0,01), increase of EF (26.5 ± 0.9 to 36.0 ± 10.8), and lower lethality (23.9% and 64.3%; RR 0.37, 95% CI 0.19-0.71), p<0.01, were found only in IST group. Significant improvement due to IST were achieved not only in V-, but also in V+ patients.

CONCLUSIONS

IST in patients with immune-mediated lymphocytic myocarditis is effective and is associated with lower lethality both in virus-negative and virus-positive patients.

A Toolbox of Potential Immune-Related Therapies for Inflammatory Cardiomyopathy

Myocarditis is a multifactorial disorder, characterized by an inflammatory reaction in the myocardium, predominantly triggered by infectious agents, but also by antigen mimicry or autoimmunity in susceptible individuals. Unless spontaneously resolved, a chronic inflammatory course concludes with cardiac muscle dysfunction portrayed by ventricular dilatation, clinically termed inflammatory cardiomyopathy (Infl-CM). Treatment strategies aim to resolve chronic inflammation and preserve cardiac function. Beside standard heart failure treatments, which only play a supportive role in this condition, systemic immunosuppressants are used to diminish inflammatory cell function at the cost of noxious side effects. To date, the treatment protocols are expert-based without large clinical evidence. This review describes concept and contemporary strategies to alleviate myocardial inflammation and sheds light on potential inflammatory targets in an evidence-based order.

Autoimmunity in Acute Myocarditis: How Immunopathogenesis Steers New Directions for Diagnosis and Treatment

PURPOSE OF REVIEW

Over the last decade, myocarditis has been increasingly recognized as common cause of sudden cardiac death in young adults and heart failure overall. The purpose of this review is to discuss hypothesis of development of non-infectious myocarditis, to provide a description of the immunopathogenesis and the most common mechanisms of autoimmunity in myocarditis, and to provide an update on therapeutic options.

RECENT FINDINGS

A new entity of myocarditis is immune checkpoint inhibitor (ICI) induced myocarditis. ICIs are used in advanced cancer to "disinhibit" the immune system and make it more aggressive in fighting cancer. This novel drug class has doubled life expectancy in metastatic melanoma and significantly increased progression free survival in advanced non-small-cell lung cancer, but comes with a risk of autoimmune diseases such as myocarditis resulting from an overly aggressive immune system. Myocarditis is an inflammatory disease of the heart with major public health impact. Thorough understanding of its immunopathogenesis is crucial for accurate diagnosis and effective treatment.

Management of Myocarditis-Related Cardiomyopathy in Adults

Myocarditis is generally a mild and self-limited consequence of systemic infection of cardiotropic viruses. However, patients can develop a temporary or permanent impairment of cardiac function including acute cardiomyopathy with hemodynamic compromise or severe arrhythmias. In this setting, specific causes of inflammation are associated with variable risks of death and transplantation. Recent translational studies suggest that treatments tailored to specific causes of myocarditis may impact clinical outcomes when added to guideline-directed medical care. This review summarizes recent advances in translational research that influence the utility of endomyocardial biopsy for the management of inflammatory cardiomyopathies. Emerging therapies for myocarditis based on these mechanistic hypotheses are entering clinical trials and may add to the benefits of established heart failure treatment.

Recognition and Initial Management of Fulminant Myocarditis: A Scientific Statement From the American Heart Association

Fulminant myocarditis (FM) is an uncommon syndrome characterized by sudden and severe diffuse cardiac inflammation often leading to death resulting from cardiogenic shock, ventricular arrhythmias, or multiorgan system failure. Historically, FM was almost exclusively diagnosed at autopsy. By definition, all patients with FM will need some form of inotropic or mechanical circulatory support to maintain end-organ perfusion until transplantation or recovery. Specific subtypes of FM may respond to immunomodulatory therapy in addition to guideline-directed medical care. Despite the increasing availability of circulatory support, orthotopic heart transplantation, and disease-specific treatments, patients with FM experience significant morbidity and mortality as a result of a delay in diagnosis and initiation of circulatory support and lack of appropriately trained specialists to manage the condition. This scientific statement outlines the resources necessary to manage the spectrum of FM, including extracorporeal life support, percutaneous and durable ventricular assist devices, transplantation capabilities, and specialists in advanced heart failure, cardiothoracic surgery, cardiac pathology, immunology, and infectious disease. Education of frontline providers who are most likely to encounter FM first is essential to increase timely access to appropriately resourced facilities, to prevent multiorgan system failure, and to tailor disease-specific therapy as early as possible in the disease process.

Inflammation in myocardial disease: From myocarditis to dilated cardiomyopathy

Dilated cardiomyopathy (DCM) is a heterogeneous group of myocardial diseases clinically defined by the presence of left ventricular dilatation and contractile dysfunction. Among various causes of DCM, a progression from viral myocarditis to DCM has long been hypothesized. Supporting this possibility, studies by endomyocardial biopsy, the only method to obtain a definite diagnosis of myocarditis at present, have provided evidence of inflammation in the myocardium in DCM patients. A number of experimental studies have elucidated a cell-mediated autoimmune mechanism triggered by viral infection in the progression of myocarditis to DCM. In addition, the important role of inflammation in the pathogenesis of heart failure has been recognized, and many terms including myocarditis, inflammatory cardiomyopathy, and inflammatory DCM have been used for myocardial diseases associated with inflammation. This review discusses the pathophysiology of inflammation in the myocardium, and refers to diagnosis and treatment based on these concepts.

Targeting CD20+ B-lymphocytes in inflammatory dilated cardiomyopathy with rituximab improves clinical course: a case series

Background 

The aetiology of dilated cardiomyopathy (DCM) is highly heterogeneous including genetic and/or acquired (infective, toxic, immune, endocrine, and nutritional) factors. The major part of acquired DCM in developed countries is caused by either viral or autoimmune myocarditis. It is believed that the activation of the T-lymphocyte cell system is the major pathomechanism underlying autoimmune myocarditis and inflammatory DCM (DCMi). However, in the hearts of a subset of patients, a significant number of CD20+ B-lymphocytes can be detected too. Limited information exists on the role of B-cell-dependent mechanisms in the progression of DCMi. Particularly CD20+ B-lymphocytes, which can be targeted by anti-CD20+ B-lymphocytes antibodies or inhibitors, might contribute to the pathogenesis of myocardial damage beyond antibody production.

Case summary 

Here, we present a case series of six patients with subacute and chronic endomyocardial biopsy-proven CD20+ B-lymphocyte-associated DCMi, where symptomatic heart failure therapy, with or without combined immunosuppressive therapy with steroid-based treatment regime, was insufficient to improve cardiac function. Five patients improved clinically several weeks after a standard infusion protocol with rituximab, a chimeric monoclonal antibody against the pan-B-cell surface molecule CD20.

Discussion 

Our case series shows that CD20+ B-lymphocyte persistence can play a pathophysiologic role in a subset of DCMi patients and highlights the potential of targeting CD20+ B cells in patients with prominent CD20+ B-lymphocyte persistence.

Hidden in Heart Failure

Current diagnostic strategies fail to illuminate the presence of rare disease in the heart failure population. One-third of heart failure patients are categorised as suffering an idiopathic dilated cardiomyopathy, while others are labelled only as heart failure with preserved ejection fraction. Those affected frequently suffer from delays in diagnosis, which can have a significant impact on quality of life and prognosis. Traditional rhetoric argues that delineation of this patient population is superfluous to treatment, as elucidation of aetiology will not lead to a deviation from standard management protocols. This article emphasises the importance of identifying genetic, inflammatory and infiltrative causes of heart failure to enable patients to access tailored management strategies.

Persistent left ventricular dysfunction after acute lymphocytic myocarditis: Frequency and predictors

BACKGROUND

Persistent left ventricular (LV) systolic dysfunction in patients with acute lymphocytic myocarditis (LM) is widely unexplored.

OBJECTIVES

To assess the frequency and predictors of persistent LV dysfunction in patients with LM and reduced LVEF at admission.

METHODS AND RESULTS

We retrospectively evaluated 89 consecutive patients with histologically-proven acute myocarditis enrolled at three Italian referral hospitals. A subgroup of 48 patients with LM, baseline systolic impairment and an available echocardiographic assessment at 12 months (6-18) from discharge constituted the study population. The primary study end-point was persistent LV dysfunction, defined as LVEF <50% at 1-year, and was observed in 27/48 patients (56.3%). Higher LV end-diastolic diameter at admission (odds ratio [OR] 1.22, 95% confidence interval [CI] 1.04-1.43, p = 0.002), non-fulminant presentation (OR 8.46, 95% CI 1.28-55.75, p = 0.013) and presence of a poor lymphocytic infiltrate (OR 12.40, 95% CI 1.23-124.97, p = 0.010) emerged as independent predictors of persistent LV dysfunction at multivariate analysis (area under the curve 0.91, 95% CI 0.82-0.99). Pre-discharge LVEF was lower in patients with persistent LV dysfunction compared to the others (32%±8 vs. 53%±8, p <0.001), and this single variable showed the best accuracy in predicting the study end-point (area under the curve 0.95, 95% CI 0.89-1.00).

CONCLUSIONS

More than half of patients presenting with acute LM and LVEF <50% who survive the acute phase show persistent LV dysfunction after 1-year from hospital discharge. Features of subacute inflammatory process and of established myocardial damage at initial hospitalization emerged as predictors of this end-point.

Acute and Fulminant Myocarditis: a Pragmatic Clinical Approach to Diagnosis and Treatment

PURPOSE OF REVIEW

To review the clinical features of acute myocarditis, including its fulminant presentation, and present a pragmatic approach to the diagnosis and treatment, considering indications of American and European Scientific Statements and recent data derived by large contemporary registries.

RECENT FINDINGS

Patients presenting with acute uncomplicated myocarditis (i.e., without left ventricular dysfunction, heart failure, or ventricular arrhythmias) have a favorable short- and long-term prognosis: these findings do not support the indication to endomyocardial biopsy in this clinical scenario. Conversely, patients with complicated presentations, especially those with fulminant myocarditis, require an aggressive and comprehensive management, including endomyocardial biopsy and availability of advanced therapies for circulatory support. Although several immunomodulatory or immunosuppressive therapies have been studied and are actually prescribed in the real-world practice, their effectiveness has not been clearly demonstrated. Patients with specific histological subtypes of acute myocarditis (i.e., giant cell and eosinophilic myocarditis) or those affected by sarcoidosis or systemic autoimmune disorders seem to benefit most from immunosuppression. On the other hand, no clear evidence supports the use of immunosuppressive agents in patients with lymphocytic acute myocarditis, even though small series suggest a potential benefit. Acute myocarditis is a heterogeneous condition with distinct pathophysiological pathways. Further research is mandatory to identify factors and mechanisms that may trigger/maintain or counteract/repair the myocardial damage, in order to provide a rational for future evidence-based treatment of patients affected by this condition.