The investigators have created a way of quickly collecting information in a large scale young population regarding the presence of some severity indicators that may allow us to classify them into: seemingly "low risk" and possible "elevated risk" for the presence of heart disease. It would have to be a short questionnaire, in order to receive a great adherence but that could simultaneously provide precise information, with an adequate description of symptoms and warning signs, in a way that a triage in the young adult population could be performed in the general young adult population in order to select individuals with an indication for personalized clinical evaluation and possible need of complementary diagnostic means. Based on this premise the investigators have developed a fast-response questionnaire named the Sudden Cardiac Death Screening Of risk factorS (SCD-SOS). This questionnaire has already been tested in a population of approximately 1500 young adults, and some changes have been introduced in order to refine its performance.

To best of the investigators knowledge, there are no large scale European surveys estimating the prevalence of cardiac disease and associated clinical symptoms in a non-selected (non-athlete) population of this age group.

Purpose: To screen a young adult population from central regional of Portugal for heart disease possibly associated to a high risk of Sudden Cardiac Death (SCD).

To determine the national prevalence of clinical symptoms of heart disease and of heart disease with increased risk for SCD in this age group.

To detect young adults in risk of SCD and with an indication for evaluation by a cardiologist, and possible need of:

• medical treatment
• electrophysiologic (EP) study and percutaneous ablation
• an implantable cardiovertor defibrillator
• a pacemaker
• other type of specialized cardiac intervention

Inclusion Criteria:

• 12 to 40 years of age
• Providing an informed consent

Exclusion Criteria:

• Failure to meet any of the aforementioned inclusion criteria

Recruitment will include mainly university students but also young adults involved in sport practice (professional, semi-professional and amateur athletes) or in other activities (sales, industry, etc). This way, the places for sample collection will the university departments or technical schools, students associations and other places that gather university students, shopping centers, gyms, sports venues, factories in the city surroundings. Information collection in these places will be performed under the authorization of proper entities.