Rationale and design of the CAREFUL study : The yield of CARdiogenetic scrEening in First degree relatives of sudden cardiac and UnexpLained death victims <45 years

Sudden cardiac death: A reappraisal

Sudden cardiac death (SCD) is still among the leading causes of death in women and men, accounting for over 50% of all fatal cardiovascular events in the United States. Two arrhythmia mechanisms of SCD can be distinguished as follows: shockable rhythms (ventricular fibrillation and pulseless ventricular tachycardia) and non-shockable rhythms including asystole or pulseless electrical activity. The overall prognosis of cardiac arrest due to shockable rhythms is significantly better. While the majority of SCDs is attributed to coronary artery disease or other structural heart disease, no obvious cause can be identified in 5% of all events, and those events are labeled as sudden unexplained deaths (SUD). Those unexplained events are typically caused by rare hereditary electrical disorders or arrhythmogenic cardiomyopathies. A systematic approach to the diagnosis of cardiac arrest followed by tailored therapy based on etiology has emerged in the last 10-15 years, with significant changes of medical practice and risk management of cardiac arrest victims. The aim of this review is to summarize our contemporary understanding of SCD/SUD in adults and to discuss current concepts of management and secondary prevention in cardiac arrest victims. A full discussion of the topic of primary prevention of SCD is beyond the scope of this article.

Improving usual care after sudden death in the young with focus on inherited cardiac diseases (the CAREFUL study): a community-based intervention study

AIMS

Inherited cardiac diseases play an important role in sudden death (SD) in the young. Autopsy and cardiogenetic evaluation of relatives of young SD victims identifies relatives at risk. We studied the usual care after SD in the young aimed at identifying inherited cardiac disease, and assessed the efficacy of two interventions to improve this usual care.

METHODS AND RESULTS

We conducted a community-based intervention study to increase autopsy rates of young SD victims aged 1-44 years and referral of their relatives to cardiogenetic clinics. In the Amsterdam study region, a 24/7 central telephone number and a website were available to inform general practitioners and coroners. In the Utrecht study region, they were informed by a letter and educational meetings. In two control regions usual care was monitored. Autopsy was performed in 169 of 390 registered SD cases (43.3%). Cardiogenetic evaluation of relatives was indicated in 296 of 390 cases (75.9%), but only 25 of 296 families (8.4%) attended a cardiogenetics clinic. Autopsy rates were 38.7% in the Amsterdam study region, 45.5% in the Utrecht study region, and 49.0% in the control regions. The proportion of families evaluated at cardiogenetics clinics in the Amsterdam study region, the Utrecht study region, and the control regions was 7.3, 9.9, and 8.8%, respectively.

CONCLUSIONS

The autopsy rate in young SD cases in the Netherlands is low and few families undergo cardiogenetic evaluation to detect inherited cardiac diseases. Two different interventions did not improve this suboptimal situation substantially.

Experiences, considerations and emotions relating to cardiogenetic evaluation in relatives of young sudden cardiac death victims

Relatives of young sudden cardiac death (SCD) victims are at increased risk of carrying a potentially fatal inherited cardiac disease. Hence, it is recommended to perform an autopsy on the victim and to refer his or her relatives to a cardiogenetics clinic for a full evaluation to identify those at risk and allow preventive measures to be taken. However, at present, the number of families attending a cardiogenetics clinic after the SCD of a young relative is low in the Netherlands. We performed a qualitative study and report on the experiences and attitudes of first-degree relatives who attended a cardiogenetics clinic for evaluation. In total, we interviewed nine first-degree relatives and one spouse of seven SCD victims about their experiences, considerations and emotions before attendance and at the first stage of the cardiogenetic evaluation before DNA results were available. Interviews were transcribed verbatim and analysed. Medical professionals did not have an important role in informing or referring relatives to a cardiogenetics clinic. Importantly, all participants indicated that they would have appreciated a more directive approach from medical professionals, because their mourning process hampered their own search for information and decision-making. A need to understand the cause of death and wanting to prevent another SCD event occurring in the family were the most important reasons for attending a clinic. There are possibilities to improve the information process and better support their decision-making. The multidisciplinary cardiogenetic evaluation was appreciated, but could be improved by minor changes in the way it is implemented.

Rationale and design of the CAREFUL study : The yield of CARdiogenetic scrEening in First degree relatives of sudden cardiac and UnexpLained death victims <45 years

Background. Sudden cardiac death (SCD) in the young (1-45 years) is a strong risk factor for the presence of inherited cardiac diseases in surviving first-degree relatives. Postmortem investigation of the victim and cardiogenetic evaluation of the first-degree relatives is indicated to detect inherited cardiac diseases and treat relatives at an early stage to prevent SCD. In the Netherlands, postmortem investigation is often not performed and relatives of SCD and sudden unexplained death (SUD) victims are rarely evaluated for inherited cardiac diseases.Methods. A prospective population-based follow-up study carried out in two intervention regions and two control regions. In the intervention regions a comprehensive intervention (stimulate autopsy and storage of victims DNA and the referral of first-degree relatives for cardiogenetic evaluation) is applied in a 'top down' and 'bottom up' mode. In each region, young sudden death victims are registered and for all cases performance of autopsy and evaluation of relatives in a cardiogenetics outpatient clinic will be determined.Expected results. The study will provide information on the incidence of sudden death in the young and the proportion of diagnosed inherited cardiac diseases. Moreover, the additional value of the introduction of two different preventive strategies directed at early detection of inherited cardiac diseases in first-degree relatives to usual care will be evaluated. Conclusion. The CAREFUL study will help to set a new standard of care in the evaluation of young sudden death victims and their relatives to identify the presence of inherited cardiac diseases, in order to prevent sudden death. (Neth Heart J 2010;18:286-90.).