Resultados del Grupo de Investigación en Muerte Súbita, 20 años después de su creación / The Research Group on Sudden Death and its results after 20 years

La muerte súbita representa en la actualidad uno de los principales desafíos para los sistemas sanitarios a nivel mundial dada su elevada incidencia, dramatismo en su presentación y años de vida que se pierden prematuramente como consecuencia de esta entidad. OBJETIVO: describir los antecedentes de la creación hace 20 años del Grupo de Investigación en Muerte Súbita en Cuba y mostrar sus resultados más significativos. MÉTODO: se realizó una revisión documental de los primeros 20 años de trabajo de investigación científica del Grupo de Investigación en Muerte Súbita en Cuba (1995-2014). RESULTADOS: se estudiaron 24 758 muertes naturales a las cuales se les aplicó un algoritmo diagnóstico para documentar 1 953 eventos de muerte súbita cardiovascular, que representaron el 7,8 por ciento de la mortalidad global registrada. El 98,1 por ciento de la casuística investigada correspondió a 14 municipios de la provincia La Habana. El 2 por ciento restante incluyó 26 municipios de 11 provincias del país. Los estudios han demostrado un incremento en la probabilidad para este evento en pacientes con hipertensión arterial, obesidad, diabetes mellitus, cardiopatía isquémica, necrosis miocárdica previa, tabaquismo, engrosamiento ventricular izquierdo y alteración del perfil lipídico. CONCLUSIONES: la creación del Grupo de Investigación en Muerte Súbita ha permitido, en los últimos 20 años, el diseño y ejecución de investigaciones científicas encaminadas a la caracterización epidemiológica de este problema de salud en Cuba, elementos útiles para trazar estrategias de intervención que permitan lograr una disminución sensible en la incidencia e impacto económico, familiar y social de esta entidad(AU)

Sudden death presently represents one of the main challenges for the health care systems worldwide due to high incidence, dramatic presentation and life years prematurely lost as a result of this event. OBJECTIVE: to describe the background of the creation of the research group on sudden death in Cuba twenty years ago, and to show its most significant results. METHODs: a documentary review of the first 20 years of scientific research work performed by the Research Group on Sudden Death in Cuba (1995-2014). RESULTS: twenty four thousand eight hundred and seventy six deaths of natural causes were studied and applied a diagnostic algorithm to document 1 953 events of sudden cardiovascular death accounting for 7.8 percent of recorded global mortality. In the studied casuistry, 98.1 percent went to 14 municipalities from 11 provinces. The studies showed increased probabilities for this event in patients suffering blood hypertension, obesity, diabetes mellitus, ischemia, previous myocardial necrosis, smoking, left ventricle thickening, and lipid profile impairment. CONCLUSIONS: the creation of the Research Group on Sudden Death allowed in the last twenty years designing and performing scientific research studies aimed at the epidemiological characterization of this health problem in Cuba and those are useful elements to draw up intervention strategies to significantly reduce the incidence and the economic, family and social impact of this event(AU)

Exclusión social y muerte súbita cardiaca / Social exclusion and sudden cardiac death

Anualmente fallecen en los llamados países del primer mundo de forma inesperada debido a enfermedades del corazón y los vasos sanguíneos, entre 350 000 y 400 000 personas según reportes oficiales. Esto equivale a 1 000 muertes súbitas cada día. La situación de salud en 31 de los 35 países del continente americano, donde las cardiopatías constituyen la primera causa de muerte, no dista mucho de lo observado en Occidente y Estados Unidos y es en general un problema que sigue creciendo. Existen factores de tipo médico que deben ser tomados en cuenta al analizar el comportamiento del fenómeno en cada uno de los países pero existen también factores de índole política de abordaje impostergable para lograr resultados favorables en la disminución de la morbilidad y mortalidad por enfermedades cardiovasculares y finalmente, en la mortalidad súbita. Se profundiza en la vinculación existente entre exclusión social y enfermedad cardiovascular y se plantea la interrogante de si la exclusión social juega un papel determinante en la elevada incidencia de muerte súbita cardiaca en la era actual. La respuesta a esta interrogante solo puede ser encontrada en el sistema económico, político y social que impere en las naciones. Solo globalizando las oportunidades de atención médica, incluyendo a los que tienen poco o nada tienen, no excluyendo, otorgando a todos acceso a las nuevas tecnologías en el campo de la medicina, se puede afrontar el reto del incremento de la pandemia cardiovascular en el siglo XXI y por ende, de la muerte súbita

In the so-called first world countries, 350 000 to 400 000 people die suddenly from heart and blood vessel diseases, according to official data. This means 1000 sudden deaths every day. The health situation in 31 out of the 35 countries in the American continent, where heart diseases are the first cause of death, is not very far from the situation in the United States and the Western nations since this is generally a growing problem. There are some medical factors that should be taken into account when analyzing the behaviour of this phenomenon in each country, but there are also political factors that must be approached to accomplish favourable results in the reduction of morbidity and mortality from cardiovascular diseases and of sudden cardiac mortality. The linking of social exclusion and cardiovascular disease is deeply studied. The answer to the question of whether the social exclusion presently plays a determining role in the high incidence of sudden cardiac death or not can only be found in the economic, political and social system existing in the nations. The globalization of the medical care opportunities by including rather than excluding those who have a little or nothing at all - giving everybody access to the new technologies in the medical field - is the means to face the challenge of the rise of cardiovascular pandemic in the 21st century, and hence, of the sudden death

Muerte súbita: Algunos conceptos / Sudden death: some concepts

Principales aspectos de este cuadro, principalmente su epidemiología, distribución, fisiopatología, prevención, y grupos de población afectada.

HLa-class II (DRB & DQB1) in Thai sudden unexplained death syndrome (Thai SUDS) families (Lai-Tai families).

Thai Sudden Unexplained Death Syndrome (Thai SUDS), or Lai-Tai, is a major health problem among rural residents of northeastern Thailand. The cause has been identified as a genetic disease. SUDS, a disorder found in Southeast Asia, is characterized by an abnormal electrocardiogram with ST-segment elevation in leads V1-V3, identical to that seen in Brugada Syndrome (Brugada Sign, BS) and sudden death due to ventricular fibrillation and cardiac arrest (represents an arrhythmogenic marker that identifies high-risk for SUDS). SUDS victims have a sleeping disorder (narcolepsy). The HLA-DR locus is tightly associated with narcoleptic Japanese patients and HLA-DR2, DQ haplotypes were also found in Oriental narcoleptic patients. These circumstances prompted us to study the association between the disease and HLA Class II by HLA DNA typing using a PCR-SSO method, with five Thai SUDS families (18 BS-positive subjects as the cases, and 27 BS-negatives as the controls). We found that the HLA-DRB1 *12021 allele was significantly increased in BS-positive subjects (p = 0.02; OR = 4.5), the same as the HLA-DRB1*12021-DQB1 *0301/09 haplotype (p = 0.01; OR = 7.95). Our data suggests that the HLA-DRB1* 12021 allele associated with BS and the HLA-DRB1*12021-DQB1 *0301/09 is a haplotype susceptible to arrhythmogenic markers that can identify a high risk for SUDS.

Morta súbita cardíaca no atleta / Sudden cardiac death in the athletes

Este trabalho consiste em uma revisão bibliográfica de assuntos relacionados com a morte súbita cardíaca em atletas. Obviamente, não se propõe aqui um texto definitivo sobre o tema ou discussão pormenorizada de cada assunto abordado. A proposta consiste em traçar um panorama que percorre desde as bases fisiopatológicas da morte súbita até a sua prevenção, de forma a familiarizar o leitor com o tema, suscitando a discussão e despertando o interesse para para a leitura desse assunto verdadeiramente fascinante...

Linkage analyses and SCN5A mutations screening in five sudden unexplained death syndrome (Lai-tai) families.

Sudden Unexplained Death Syndrome (SUDS) (or in Thai Lai-tai) share the same ECG pattern as Brugada Syndrome: RSR' and ST segment elevation in V1 to V3. Brugada Syndrome is a genetic disorder with the inheritance pattern of autosomal dominant (using the ECG pattern and unexplained sudden death as phenotype) and the cardiac sodium channel gene (SCN5A) mutations caused this syndrome. To determine whether SUDS was associated with the same mutations as Brugada Syndrome, the authors performed a linkage studies on 5 SUDS families with the Brugada Syndrome ECG pattern and found one family could not be excluded from linkage to SCN5A. However, the direct sequencing in 8 reported mutations on exon 5, 12, 17, 18 and 28 in this family failed to demonstrate the mutations. It was concluded that SUDS mutations maybe a novel mutation different from previously reported mutations, further genetic studies in SCN5A and other candidate genes might elucidate the molecular basis of SUDS.

Pattern of inheritance in three sudden unexplained death syndrome ("Lai-tai") families.

Sudden Unexplained Death Syndrome (SUDS) (or Lai-tai) is sudden death in previously healthy young adults without any structural cause of death from autopsy findings. Our previous data showed that familial SUDS is not X-linked recessive. The objective of this study was to determine the pattern of inheritance in familial SUDS using the ECG markers of Brugada syndrome (RBBB and ST-segment elevation in V1 to V3), SUDS and presumptive SUDS as phenotypes. We employed the standard 12-lead ECG and higher intercostal space (ICS) V1 to V3 (-V1 to -V3 and -2V1 to -2V3) leads ECG in SUDS relatives after procainamide and drew the pedigree. We studied 62 relatives of 9 SUDS victims who died in Singapore and selected 3 families (n = 34) for the procainamide test and ECG. The mean age was 36.4 +/- 23.6 years (4-78 years). Three SUDS families showed the same pattern of inheritance of autosomal dominant.