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The term MINOCA (myocardial infarction with non-obstructive coronary arteries) defines acute myocardial infarction with angiographic evidence of no significant coronary artery stenosis. Heterogeneous diseases are labelled as MINOCA. Incidence and epidemiological aspects differ on the basis of etiological causes. MINOCA include plaque (causing50% stenosis) rupture or erosion, coronary embolism and dissection, and coronary artery spasm. Diagnosis may require multiple diagnostic tools, including cardiac imaging or provocative tests, in addition to standard coronary angiography, according to clinical suspicion. Cardiac magnetic resonance plays a key role in confirming the diagnosis and excluding other diseases with similar clinical presentation. Prognosis is not as benign as previously thought, on the opposite it is characterized by morbidity and mortality rates similar to other forms of myocardial infarction. Once the causative mechanism has been identified, appropriate therapy can be delivered.

Endomyocardial biopsy (EMB) is the gold standard for the diagnosis of myocarditis. Patients with clinical presentation consistent with myocarditis and acute heart failure should undergo EMB, in particular to exclude giant-cell myocarditis or necrotizing eosinophilic myocarditis that are life-threatening conditions. The indication for EMB is debatable in case of suspected myocarditis with infarct-like presentation and preserved left ventricular ejection fraction. In fact, in this group of patients the prognosis is fairly good, and the clinical advantage to reach a histological diagnosis by means of an invasive procedure with potential complications such as EMB is limited. In this article we discuss the indication for EMB in the light of current guidelines based on existing consensus documents.

Churg-Strauss syndrome, recently renamed eosinophilic granulomatosis with polyangiitis (EGPA), is a rare form of systemic vasculitis, characterized by disseminated necrotizing vasculitis with extravascular granulomas occurring among patients with asthma and tissue eosinophilia. EGPA is classified as a small and medium-sized vessel vasculitis associated with antineutrophil cytoplasmic antibodies (ANCA) and the hypereosinophilic syndrome. Typical clinical features include asthma, sinusitis, transient pulmonary infiltrates and neuropathy. Blood eosinophils are often1500/µl or more than 10% on the differential leukocyte count. Blood eosinophils should always be tested in unexplained cardiac disorders, and may normalize even after low doses of corticosteroids. ANCA are positive in 40-60% of cases, mainly anti-myeloperoxidase. Heart involvement occurs in approximately 15-60% of EGPA patients, especially those who are ANCA negative. Any cardiac structure can be involved, and patients present with myocarditis, heart failure, pericarditis, arrhythmia, coronary arteritis, valvulopathy, intracavitary cardiac thrombosis. Although cardiovascular involvement is usually an early manifestation, it can also occur later in the course of the disease. A significant proportion of patients with cardiac involvement is asymptomatic. In the absence of symptoms and major ECG abnormalities, cardiac involvement may be detected in nearly 40% of the patients. All patients with EGPA should be studied not only with a detailed history of cardiac symptoms and ECG, but also with echocardiography; if abnormalities are detected, a cardiac magnetic resonance study should be performed. Coronary angiography and endomyocardial biopsy should be reserved to selected cases. Heart involvement carries a poor prognosis and causes 50% of the deaths of these patients. It is often insidious and underestimated. Optimal therapy is therefore important and based on high-dose corticosteroids plus immunosuppressive agents, particularly cyclophosphamide in case of myocardial inflammation. Thus, early diagnosis of cardiac involvement and subsequent therapy may prevent progression of cardiac disease. At present, the role of troponin and brain natriuretic peptide in monitoring and therapy remains unclear. Orthotopic heart transplantation is feasible in case of severe disease, even if the experience is limited in -EGPA, and optimal post-transplantation immunosuppressive strategy has yet to be defined.

Ventricular aneurysm as late complication has been described in cardiac sarcoidosis and occasionally in giant cell myocarditis. The images from the present case of ventricular aneurysm formation as a late complication of giant cell myocarditis underline a potential cause of sudden arrhythmic death in patients who survive this life-threatening condition in the absence of recurrent inflammation and with preserved left ventricular ejection fraction. Follow-up with cardiac magnetic resonance can detect small aneurysms, and an implantable cardioverter-defibrillator may be considered when this complication occurs.

The role of the right ventricle has often been underestimated in heart failure. It has been thought that the right cavity has a less prominent impact on symptoms, therapeutic approach, and prognosis. Right ventricular dysfunction is a complex issue and its diagnosis has acquired a relevant role, in particular with the improvement of new therapeutic options such as ventricular assist devices. The complex geometry of the right ventricle and its interaction with the left ventricle are still a matter of debate, leaving several open questions about the best therapeutic approach to manage right ventricular dysfunction. Echocardiography remains the first-line imaging technique, but an integrated multimodality evaluation with clinical, biochemical and hemodynamic parameters, and cardiovascular magnetic resonance imaging can provide a more comprehensive way to choose the most appropriate treatment for patients with heart failure associated with right ventricular dysfunction.

Heart transplantation (HTx) is considered to be the gold standard treatment for advanced heart failure (HF) but it is available only for a minority of patients, due to paucity of donor hearts (278 HTx were performed in 2011 in Italy). Patients listed for HTx have a prolonged waiting time (that is about 2.3 years in the 2006-2010 time period in Italy) that is superior compared with patients who receive HTx (median time around 6 months), to underline the presence of an allocation system that prioritizes candidates in critical conditions. Patients listed for HTx have a poor quality of life and their annual mortality is around 8-10%. Another 10-15% of HTx candidates are removed from the waiting list each year because they are no longer suitable for transplantation. On the other hand, continuous-flow left ventricular assist devices (LVADs) have been demonstrated to improve survival and quality of life of patients with advanced/refractory HF. LVAD therapy can represent a valid alternative to HTx, and it is recommended for patients with advanced HF in the recent edition of the European Society of Cardiology guidelines on HF management. In the United States, a larger number of centers compared with European ones started to apply a strategy of LVAD implant for many patients who meet clinical criteria for listing for HTx. Data from our center concerning the last 6 years of LVAD implant (51 implants since 2006) reported a 75.5% survival rate at 1 year. In Italian series, as in our center, current HTx survival is only slightly superior (83% survival rate at 1 year), based on data from the Italian National Transplant Center. We report a proposal for updated listing criteria for HTx and indications for LVAD implant in patients with advanced acute and chronic HF. Criteria for identifying suitable patients for HTx and/or LVAD considering the shortage of donors are discussed.

The mid- and long-term outcome of revascularization procedures is still uncertain in patients with chronic left ventricular systolic dysfunction due to coronary artery disease. The identification of dysfunctional myocardial segments with residual viability that can improve after revascularization is pivotal for further patient management. Hibernating myocardium (chronically dysfunctional but still viable tissue) can be identified by positron emission tomography and cardiac magnetic resonance and its presence and extent can predict functional recovery after revascularization. Before beta-blockers were introduced as routine care for heart failure, surgical revascularization appeared to improve survival in these patients. Nowadays, novel medical treatments and devices such as cardiac resynchronization therapy and implantable cardioverter-defibrillators have improved prognosis of these patients and their use is supported by a number of clinical trials. A recently concluded randomized trial, the STICH (Surgical Treatment for Ischemic Heart Failure) trial, has assessed the prognostic benefit derived from revascularization added to optimal medical therapy in patients with ischemic left ventricular dysfunction. This is an overview of the pathophysiological mechanisms as well as the main clinical studies and meta-analyses that have addressed this issue in the past four decades. Furthermore, a brief proposal for a randomized trial to assess effect on prognosis of revascularization of hibernating myocardium will be presented.