The incidence of sudden cardiac death (Sudden Cardiac Death, SCD), despite the efforts of clinicians, is continuously increasing. In an important subset of cases, SCD remains completely unexplained, the post-mortem examination is negative, with normal cardiac structure and there are no other possible causes of sudden death. This form of sudden cardiac death (SCD) is described as Sudden Unexpected Death Syndrome (SUDS), but also as Sudden Arrhythmia Death Syndrome or Idiopathic Ventricular Fibrillation. The majority of these cases recognizes as a cause of the event fatal cardiac electrical disorder. The Sudden Cardiac Death is therefore a devastating manifestation of occult cardiac disease, mainly affects young adults and is particularly difficult to predict risk in family members. The practice of the autopsy in the case of Sudden Death is not widespread nor as molecular autopsy, especially in the face of pathological findings of normality, so a reliable estimate of the true incidence of SUDS is difficult to obtain. Some studies of survivors of cardiac arrest have reported prevalence rates of SUDS around 5%, with a range in the general population around 3/100.000 year. In the general population males are more likely to SCD or SUDS with percentages varying between 63-68% of cases and with an average age between 24-32 years, however a detailed research of heart disease can highlight gender differences. The need to understand the causes of sudden cardiac death related to unexpected stresses the importance that in these cases it runs a complete and detailed post-mortem examination including a histological evaluation of the myocardium; also the discovery of the genetic causes of SCD and the ability to identify the responsible genes has expanded the possibilities of investigation is on blood samples collected from subjects survivors of myocardial tissue obtained post-mortem with defined techniques of molecular autopsy. The primary electrical disease that can lead to sudden death, although sometimes sporadic, have the character of heredity and the mechanism of gene identification is the first step for a program of primary prevention. Gene mutations in this group of pathologies affecting the function of the cardiac ion channels by altering the complex balance of currents in the action potential and are therefore defined channelopathies (channelopathies). In this group the long QT syndrome, short QT syndrome, Brugada syndrome, catecholaminergic ventricular tachycardia. Recently, some electrocardiographic pattern of early repolarization, located in the lower and inferior-lateral, have been associated with risk of malignant arrhythmias. Furthermore, as part of sudden deaths associated with particular subgroups of patients, there was an incidence of sudden cardiac death and unexpected significantly higher in the population of epileptic patients with an incidence 24 times higher than the general population (SUDEP: sudden and unexpected death in patients with epilepsy not caused by accidental or status epilepticus, and a post mortem examination and toxicological studies that explain the cause "). The proposed study involves the establishment of a Regional Register for sudden cardiac death with special reference to channelopathies. Patient recruitment will involve all hospital cardiologists, university and outpatient Region of Sardinia. Will be included in the study with patients younger than 50 years:

1. Died of sudden cardiac death with autopsy negative.
2. Channelopathy with diagnosed or suspected:
   1. Channelopathy already diagnosed.
   2. Channelopathy for suspected symptoms or ECG signs:
      • Survivors of cardiac arrest with negative cardiac imaging techniques (idiopathic ventricular fibrillation).
      • Patients with a history of syncope etiology is not defined and / or episodes of nocturnal agonal respiration
      • Patients <40 years who exhibit episodes of "lone atrial fibrillation" in the absence of structural heart
      • Family history of channelopathies already diagnosed.
      • Family history of sudden cardiac death in the absence of structural heart
      • Idiopathic epilepsy (in collaboration with the centers of neurology and neuropsychiatry)
3. Each of these patients will be evaluated by a team of cardiologists with experience in management of arrhythmic disorders and subjected to instrumental examinations dedicated to the diagnosis of channelopathies. In all probands will run completely for a genetic study of causative genetic mutations. All patients who meet the inclusion criteria will be included in a data base managed by a cardiologist experienced in the management of Sudden Cardiac Death

Ethics Committee Approval