[Hypertrophic cardiomyopathy and sudden death]. / Cardiomiopatia ipertrofica e morte improvvisa.

Hypertrophic cardiomyopathy is a primary and usually familial cardiac disorder characterized by a genetic, pathophysiologic and clinical complexity. The natural history of the disease is extremely heterogenous: many patients have no or mild symptoms and a near-normal longevity, some develop severe symptoms of heart failure, and others die suddenly often at a young age and in the absence of previous symptoms. Although sudden and unexpected cardiac death may occur at any age in hypertrophic cardiomyopathy, this devastating event is the most common modality of death in children and young patients. Despite intense investigation, risk stratification remains a major challenge. This paper examines the present knowledge on risk assessment and treatment strategies for the prevention of sudden death.

Role of echocardiography in acute chest pain syndrome.

Fewer than one third of patients presenting to the emergency department with complaints of chest pain have an acute coronary syndrome. The electrocardiogram provides a specific diagnosis only in 40% of patients with acute myocardial infarction. The presence of regional wall-motion abnormalities at echocardiography in patients without known coronary artery disease is a moderate indicator of an increased likelihood of acute myocardial ischemia or myocardial infarction with a positive predictive accuracy of about 50%. More important, the absence of regional wall-motion abnormalities identifies a subset of patients unlikely to have a myocardial infarction with a negative predictive accuracy of about 95%. Echocardiography can provide incremental prognostic information to identify patients at risk of early or late cardiac events, even after consideration of clinical, historical, and electrocardiographic variables. The application of new contrast agents to echocardiography will probably allow an early and more accurate evaluation of patients with chest pain of uncertain significance.

[From the great clinical studies to the management of the single patient. Medical therapy in the pre- and post-fibrinolytic era]. / Dai grandi studi clinici alla gestione del singolo paziente. La terapia medica nell'era pre e post-fibrinolitica.

Medical therapy of myocardial infarction has changed over the last 30 years. The "lag phenomenon", i.e. the time lapsing from the appraisal of a new, relevant scientific evidence and its practical adoption, has been variable, and different from one treatment to another. It has been very short for GP IIb/IIIa receptor inhibitors in candidates for urgent coronary angioplasty after myocardial infarction, short for ACE inhibitors, and it has been also short for the decrease in the prescription of calcium channel inhibitors after controversial scientific evidence. This time lapse has been long for beta-blockers, that only now are used quite extensively in Italy: from less than 10% of hospitalized patients during the early '80s, to over 60% nowadays. This evolution of medical therapy has been progressive and continuous, has not been divided into two eras, and thrombolysis seems to have little to do with it. The extensive introduction of thrombolysis has simply divided patients with acute myocardial infarction into two subgroups, very different for clinical characteristics: candidates for this therapy, and "others". Candidates for thrombolysis have a much better prognosis, but for a "paradox effect" they have been studied much more than the others. Now, the bulk of publications concerning patients undergoing thrombolysis carries the risk of spreading the concept that myocardial infarction has changed. We do not think that this corresponds to reality. Probably, the concepts that have guided medical therapy have been very similar and unchanged over the years, and both medical and surgical plus coronary angioplasty therapies are today much more appropriately used than yesterday.

Multiplane transesophageal echocardiography and stroke.

Transesophageal echocardiography (TEE) is considered a basic tool in the diagnostic and follow-up evaluation of stroke patients, since up to 40% of cerebral ischemic events are presumed to have a cardiac origin. TEE offers a superior resolution of the posterior cardiac structures, such as left atrium and appendage and atrial septum, as well as of the aorta. By means of TEE, evidence has accumulated that some cardiovascular abnormalities (left-sided thrombi, tumors and vegetative lesions, complicated plaques of the aortic arch) are associated with ischemic stroke. Nevertheless, some issues remain unresolved. Will exclusion of atrial thrombus by multiplane TEE preclude embolism after cardioversion of atrial fibrillation? If anticoagulation before and after cardioversion is needed to provide adequate protection against embolism, will TEE be indicated in all patients? Moreover, can the detection of spontaneous echo contrast or enlarged and hypokinetic left atrial appendage in atrial fibrillation modify the therapeutic strategy? Is atrial septal aneurysm (ASA) a real embolic source, particularly when a right-to-left shunt is not associated? Considering the high prevalence of patent foramen ovale (PFO) in normal subjects, how can we identify patients at higher risk of embolism? Furthermore, methodologic points have to be taken into account when we analyze data from the literature. First, most studies are retrospective; a sole prospective study demonstrated that atherosclerotic plaques >4 mm thick in the aortic arch are significant predictors of recurrent brain infarction and other cardiovascular events in patients > or =60 years of age. Second, the association between the aforementioned cardiac abnormalities (mainly ASA and PFO) and cardiogenic embolism is biased by the patient-enrollment criteria used in those studies so that their pathogenetic role has not yet been established. Prospective studies with the enrollment of appropriate control groups will be necessary to define what can be considered a marker of embolic risk; the diagnosis "cardiogenic embolism" will not be a definitive diagnosis in most cases.