What's new in myocarditis?

Macrophages in cardiovascular diseases: molecular mechanisms and therapeutic targets

The immune response holds a pivotal role in cardiovascular disease development. As multifunctional cells of the innate immune system, macrophages play an essential role in initial inflammatory response that occurs following cardiovascular injury, thereby inducing subsequent damage while also facilitating recovery. Meanwhile, the diverse phenotypes and phenotypic alterations of macrophages strongly associate with distinct types and severity of cardiovascular diseases, including coronary heart disease, valvular disease, myocarditis, cardiomyopathy, heart failure, atherosclerosis and aneurysm, which underscores the importance of investigating macrophage regulatory mechanisms within the context of specific diseases. Besides, recent strides in single-cell sequencing technologies have revealed macrophage heterogeneity, cell-cell interactions, and downstream mechanisms of therapeutic targets at a higher resolution, which brings new perspectives into macrophage-mediated mechanisms and potential therapeutic targets in cardiovascular diseases. Remarkably, myocardial fibrosis, a prevalent characteristic in most cardiac diseases, remains a formidable clinical challenge, necessitating a profound investigation into the impact of macrophages on myocardial fibrosis within the context of cardiac diseases. In this review, we systematically summarize the diverse phenotypic and functional plasticity of macrophages in regulatory mechanisms of cardiovascular diseases and unprecedented insights introduced by single-cell sequencing technologies, with a focus on different causes and characteristics of diseases, especially the relationship between inflammation and fibrosis in cardiac diseases (myocardial infarction, pressure overload, myocarditis, dilated cardiomyopathy, diabetic cardiomyopathy and cardiac aging) and the relationship between inflammation and vascular injury in vascular diseases (atherosclerosis and aneurysm). Finally, we also highlight the preclinical/clinical macrophage targeting strategies and translational implications.

Combination of echocardiography and emergency endomyocardial biopsy for suspected myocarditis in the cardiovascular emergency medical care

Myocarditis is a fatal inflammatory disease of myocardium, diagnosed with clinical and histopathological findings by endomyocardial biopsy (EMB). Myocarditis has a variety of clinical presentations and a dynamic and sometimes rapid process of severity. Echocardiography plays an important role in the management of myocarditis because it has noninvasiveness and portability. Once acute myocarditis is suspected by an echocardiography, pathological information should be required as early as possible. In our cardiovascular center, emergency EMB suspecting myocarditis was performed in 19 cases (1.3%) among consecutive 1469 cases (70.1 ± 12.6 years old, male 67.5%) undergoing emergency coronary angiograms from April 2014 to September 2017. Hematoxylin-eosin stain of the biopsy specimens were prepared with microwave-accelerated histoprocessing within 3-5 hours after EMB for rapid pathological diagnosis of myocarditis. We reviewed the value of emergency echo-EMB combination leading to the early decision making of intensive care, corticosteroids and proper mechanical circulatory support prior to the possible sudden collapse in patients with myocarditis.

Chinese society of cardiology expert consensus statement on the diagnosis and treatment of adult fulminant myocarditis

Fulminant myocarditis is primarily caused by infection with any number of a variety of viruses. It arises quickly, progresses rapidly, and may lead to severe heart failure or circulatory failure presenting as rapid-onset hypotension and cardiogenic shock, with mortality rates as high as 50%-70%. Most importantly, there are no treatment options, guidelines or an expert consensus statement. Here, we provide the first expert consensus, the Chinese Society of Cardiology Expert Consensus Statement on the Diagnosis and Treatment of Fulminant Myocarditis, based on data from our recent clinical trial (NCT03268642). In this statement, we describe the clinical features and diagnostic criteria of fulminant myocarditis, and importantly, for the first time, we describe a new treatment regimen termed life support-based comprehensive treatment regimen. The core content of this treatment regimen includes (i) mechanical life support (applications of mechanical respirators and circulatory support systems, including intraaortic balloon pump and extracorporeal membrane oxygenation, (ii) immunological modulation by using sufficient doses of glucocorticoid, immunoglobulin and (iii) antiviral reagents using neuraminidase inhibitor. The proper application of this treatment regimen may and has helped to save the lives of many patients with fulminant myocarditis.

Fulminant myocarditis: Characteristics, treatment, and outcomes

Myocarditis is an inflammatory disease of the myocardium with a broad spectrum of clinical presentations, ranging from mild symptoms to severe heart failure. The course of patients with myocarditis is heterogeneous, varying from partial or full clinical recovery in few days to advanced low cardiac output syndrome requiring mechanical circulatory support or heart transplantation. Fulminant myocarditis (FM) is a peculiar clinical condition and is an acute form of myocarditis, whose main characteristic is a rapidly progressive clinical course with the need for hemodynamic support. Despite the common medical belief of the past decades, recent comprehensive data, including a recent registry that compared FM with acute non-FM, highlighted that FM has a poor inhospital outcome, often requires advanced hemodynamic support, and may result in residual left ventricular dysfunction in survivors. This review aimed to provide an updated practical definition of FM, including essentials in the diagnosis and management of the disease. Finally, the outcome of FM was critically revised according to the current published registries focusing on the topic.