RESUMO
AIMS: The majority of sudden cardiac arrests (SCAs) occur in patients with left-ventricular (LV) ejection fraction (LVEF) >35%, yet there are no methods for effective risk stratification in this sub-group. Since abnormalities of LV geometry can be identified even with preserved LVEF, we investigated the potential impact of LV geometry as a novel risk marker for this patient population. METHODS AND RESULTS: In the ongoing Oregon Sudden Unexpected Death Study, SCA cases with archived echocardiographic data available were prospectively identified during 2002-15, and compared with geographical controls. Analysis was restricted to subjects with LVEF >35%. Based on established measures of LV mass and relative wall thickness (ratio of wall thickness to cavity diameter), four different LV geometric patterns were identified: normal geometry, concentric remodelling, concentric hypertrophy, and eccentric hypertrophy. Sudden cardiac arrest cases (n = 307) and controls (n = 280) did not differ in age, sex, or LVEF, but increased LV mass was more common in cases. Twenty-nine percent of SCA cases presented with normal LV geometry, 35% had concentric remodelling, 25% concentric hypertrophy, and 11% eccentric hypertrophy. In multivariate model, concentric remodelling (OR 1.76; 95%CI 1.18-2.63; P = 0.005), concentric hypertrophy (OR 3.20; 95%CI 1.90-5.39; P < 0.001), and eccentric hypertrophy (OR 2.47; 95%CI 1.30-4.66; P = 0.006) were associated with increased risk of SCA. CONCLUSION: Concentric and eccentric LV hypertrophy, but also concentric remodelling without hypertrophy, are associated with increased risk of SCA. These novel findings suggest the potential utility of evaluating LV geometry as a potential risk stratification tool in patients with preserved or moderately reduced LVEF.
Assuntos
Morte Súbita Cardíaca/etiologia , Hipertrofia Ventricular Esquerda/complicações , Volume Sistólico , Função Ventricular Esquerda , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Distribuição de Qui-Quadrado , Ecocardiografia , Feminino , Humanos , Hipertrofia Ventricular Esquerda/diagnóstico por imagem , Hipertrofia Ventricular Esquerda/mortalidade , Hipertrofia Ventricular Esquerda/fisiopatologia , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Razão de Chances , Oregon , Prognóstico , Estudos Prospectivos , Medição de Risco , Fatores de Risco , Fatores de Tempo , Remodelação VentricularRESUMO
AIMS: Delayed QRS transition zone in the precordial leads of the 12-lead electrocardiogram (ECG) has been recently associated with increased risk of sudden cardiac death (SCD), but the underlying mechanisms are unknown. We correlated echocardiographic findings with ECG and clinical characteristics to investigate how alterations in cardiac structure and function contribute to this risk marker. METHODS AND RESULTS: From the ongoing population-based Oregon Sudden Unexpected Death Study (catchment population â¼1 million), SCD cases with prior ECG available (n = 627) were compared with controls (n = 801). Subjects with delayed transition at V5 or later were identified, and clinical and echocardiographic patterns associated with delayed transition were analysed. Delayed transition was present in 31% of the SCD cases and 17% of the controls. These subjects were older and more likely to have cardiovascular risk factors and history of myocardial infarction. Delayed transition was associated with increased left ventricular (LV) mass (122.7 ± 40.2 vs. 102.9 ± 33.7 g/m2; P < 0.001), larger LV diameter (53.3 ± 10.4 vs. 49.2 ± 8.0 mm; P < 0.001), and lower LV ejection fraction (LVEF) (46.4 ± 15.7 vs. 55.6 ± 12.5%; P < 0.001). In multivariate analysis, delayed transition was independently associated with myocardial infarction, reduced LVEF, and LV hypertrophy. The association between delayed transition and SCD was independent of the LVEF (OR 1.57; 95% CI 1.04-2.38; P = 0.032). CONCLUSION: The underpinnings of delayed QRS transition zone extend beyond previous myocardial infarction and reduced LVEF. Since the association with sudden death is independent of these factors, this novel marker of myocardial electrical remodelling should be explored as a potential risk predictor of SCD.
Assuntos
Morte Súbita Cardíaca/epidemiologia , Eletrocardiografia/métodos , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/mortalidade , Disfunção Ventricular Esquerda/diagnóstico , Disfunção Ventricular Esquerda/mortalidade , Distribuição por Idade , Idoso , Causalidade , Comorbidade , Eletrocardiografia/estatística & dados numéricos , Feminino , Humanos , Masculino , Oregon/epidemiologia , Prevalência , Reprodutibilidade dos Testes , Fatores de Risco , Sensibilidade e Especificidade , Taxa de SobrevidaRESUMO
BACKGROUND: Survival after sudden cardiac arrest (SCA) remains low, and tools for improved prediction of patients at long-term risk for SCA are lacking. Alternative short-term approaches aimed at preemptive risk stratification and prevention are needed. OBJECTIVE: To assess characteristics of symptoms in the 4 weeks before SCA and whether response to these symptoms is associated with better outcomes. DESIGN: Ongoing prospective population-based study. SETTING: Northwestern United States (2002 to 2012). PATIENTS: Residents aged 35 to 65 years with SCA. MEASUREMENT: Assessment of symptoms in the 4 weeks preceding SCA and association with survival to hospital discharge. RESULTS: Of 839 patients with SCA and comprehensive assessment of symptoms (mean age, 52.6 years [SD, 8]; 75% men), 430 (51%) had warning symptoms (50% of men vs. 53% of women; P = 0.59), mainly chest pain and dyspnea. In most symptomatic patients (93%), symptoms recurred within the 24 hours preceding SCA. Only 81 patients (19%) called emergency medical services (911) to report symptoms before SCA; these persons were more likely to be patients with a history of heart disease (P < 0.001) or continuous chest pain (P < 0.001). Survival when 911 was called in response to symptoms was 32.1% (95% CI, 21.8% to 42.4%) compared with 6.0% (CI, 3.5% to 8.5%) in those who did not call (P < 0.001). LIMITATION: Potential for recall and response bias, symptom assessment not available in 24% of patients, and missing data for some patients and SCA characteristics. CONCLUSION: Warning symptoms frequently occur before SCA, but most are ignored. Emergent medical care was associated with survival in patients with symptoms, so new approaches are needed for short-term prevention of SCA. PRIMARY FUNDING SOURCE: National Heart, Lung, and Blood Institute.
Assuntos
Parada Cardíaca/diagnóstico , Parada Cardíaca/mortalidade , Adulto , Idoso , Dor no Peito/etiologia , Dispneia/etiologia , Serviços Médicos de Emergência/estatística & dados numéricos , Feminino , Parada Cardíaca/prevenção & controle , Humanos , Masculino , Pessoa de Meia-Idade , Noroeste dos Estados Unidos/epidemiologia , Estudos Prospectivos , Fatores de Risco , Análise de Sobrevida , Fatores de TempoRESUMO
BACKGROUND: Sports-associated sudden cardiac arrests (SCAs) occur mostly during middle age. We sought to determine the burden, characteristics, and outcomes of SCA during sports among middle-aged residents of a large US community. METHODS AND RESULTS: Patients with SCA who were 35 to 65 years of age were identified in a large, prospective, population-based study (2002-2013), with systematic and comprehensive assessment of their lifetime medical history. Of the 1247 SCA cases, 63 (5%) occurred during sports activities at a mean age of 51.1±8.8 years, yielding an incidence of 21.7 (95% confidence interval, 8.1-35.4) per 1 million per year. The incidence varied significantly by sex, with a higher incidence among men (relative risk, 18.68; 95% confidence interval, 2.50-139.56) for sports SCAs compared with all other SCAs (relative risk 2.58; 95% confidence interval, 2.12-3.13). Sports SCA was also more likely to be a witnessed event (87% versus 53%; P<0.001) with cardiopulmonary resuscitation (44% versus 25%; P=0.001) and ventricular fibrillation (84% versus 51%; P<0.0001). Survival to hospital discharge was higher for sports-associated SCA (23.2% versus 13.6%; P=0.04). Sports SCA cases presented with known preexisting cardiac disease in 16% and ≥1 cardiovascular risk factors in 56%, and overall, 36% of cases had typical cardiovascular symptoms during the week preceding the SCA. CONCLUSIONS: Sports-associated SCA in middle age represents a relatively small proportion of the overall SCA burden, reinforcing the idea of the high-benefit, low-risk nature of sports activity. Especially in light of current population aging trends, our findings emphasize that targeted education could maximize both safety and acceptance of sports activity in the older athlete.
Assuntos
Parada Cardíaca Extra-Hospitalar/epidemiologia , Esportes , Adulto , Fatores Etários , Cardiomiopatia Dilatada/complicações , Cardiomiopatia Hipertrófica/complicações , Reanimação Cardiopulmonar/estatística & dados numéricos , Comorbidade , Doença das Coronárias/complicações , Morte Súbita Cardíaca/epidemiologia , Serviços Médicos de Emergência/estatística & dados numéricos , Feminino , Cardiopatias Congênitas/complicações , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Oregon/epidemiologia , Parada Cardíaca Extra-Hospitalar/etiologia , Parada Cardíaca Extra-Hospitalar/terapia , Estudos Prospectivos , Risco , Estações do Ano , Fatores Sexuais , População Urbana/estatística & dados numéricos , Fibrilação Ventricular/epidemiologia , Fibrilação Ventricular/terapiaRESUMO
BACKGROUND: Sudden cardiac arrest (SCA) is a major contributor to mortality, but data are limited among nonwhites. Identification of differences in clinical profile based on race may provide opportunities for improved SCA prevention. METHODS AND RESULTS: In the ongoing Oregon Sudden Unexpected Death Study (SUDS), individuals experiencing SCA in the Portland, OR, metropolitan area were identified prospectively. Patient demographics, arrest circumstances, and pre-SCA clinical profile were compared by race among cases from 2002 to 2012 (for clinical history, n=126 blacks, n=1262 whites). Incidence rates were calculated for cases from the burden assessment phase (2002-2005; n=1077). Age-adjusted rates were 2-fold higher among black men and women (175 and 90 per 100 000, respectively) compared with white men and women (84 and 40 per 100 000, respectively). Compared with whites, blacks were >6 years younger at the time of SCA and had a higher prearrest prevalence of diabetes mellitus (52% versus 33%; P<0.0001), hypertension (77% versus 65%; P=0.006), and chronic renal insufficiency (34% versus 19%; P<0.0001). There were no racial differences in previously documented coronary artery disease or left ventricular dysfunction, but blacks had more prevalent congestive heart failure (43% versus 34%; P=0.04) and left ventricular hypertrophy (77% versus 58%; P=0.02) and a longer QTc interval (466±36 versus 453±41 milliseconds; P=0.03). CONCLUSIONS: In this US community, the burden of SCA was significantly higher in blacks compared with whites. Blacks with SCA had a higher prearrest prevalence of risk factors beyond established coronary artery disease, providing potential targets for race-specific prevention.
Assuntos
População Negra/etnologia , Morte Súbita Cardíaca/etnologia , Morte Súbita Cardíaca/epidemiologia , População Branca/etnologia , Idoso , Idoso de 80 Anos ou mais , População Negra/estatística & dados numéricos , Morte Súbita Cardíaca/etiologia , Complicações do Diabetes/complicações , Complicações do Diabetes/epidemiologia , Complicações do Diabetes/etnologia , Feminino , Humanos , Hipertensão/complicações , Hipertensão/epidemiologia , Hipertensão/etnologia , Incidência , Masculino , Pessoa de Meia-Idade , Oregon , Prevalência , Estudos Prospectivos , Insuficiência Renal Crônica/complicações , Insuficiência Renal Crônica/epidemiologia , Insuficiência Renal Crônica/etnologia , Estudos Retrospectivos , Fatores de Risco , População Branca/estatística & dados numéricosRESUMO
INTRODUCTION: Improvements in risk stratification for sudden cardiac arrest (SCA) will require discovery of markers that extend beyond the LV ejection fraction (LVEF). The frontal QRS-T angle has been shown to predict risk of SCA but the value of this marker independent of the LVEF has not been investigated. METHODS AND RESULTS: Cases of adult SCA with an archived electrocardiogram (12-lead ECG) available before the event, with a computable frontal QRS-T angle, were identified from the Oregon Sudden Unexpected Death Study (Oregon SUDS) ongoing in the Portland, Oregon metro area. A total of 666 SCA cases (mean age 67.2 years; 95% CI, 52.3-82.1 years; 68.6% males) were compared to 863 controls (mean age 66.6 years, 55.2-78.0 years; 68.1% males; 75.0% had CAD) from the same geographical region. The mean frontal QRS-T angle was wider in cases (74(o) ; 95% CI, 17(o) -131(o) ) compared to controls (51(o) ; 95% CI, 5(o) -97(o;) P< 0.0001). A frontal QRS-T angle of more than 90(o) remained associated with increased risk of SCD after adjusting for age, gender, heart rate, prolonged intraventricular conduction, electrocardiographic left ventricular hypertrophy (ECG LVH), baseline comorbidities, and left ventricular ejection fraction (LVEF) (OR 2.2; 95% CI, 1.60-3.09; P< 0.0001). CONCLUSION: A wide QRS-T angle greater than 90(o) is associated with an increased risk of SCA independent of the left ventricular ejection fraction.
Assuntos
Potenciais de Ação , Arritmias Cardíacas/diagnóstico , Morte Súbita Cardíaca/etiologia , Eletrocardiografia , Volume Sistólico , Função Ventricular Esquerda , Idoso , Idoso de 80 Anos ou mais , Arritmias Cardíacas/complicações , Arritmias Cardíacas/mortalidade , Arritmias Cardíacas/fisiopatologia , Estudos de Casos e Controles , Distribuição de Qui-Quadrado , Feminino , Frequência Cardíaca , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Razão de Chances , Oregon , Valor Preditivo dos Testes , Prognóstico , Medição de Risco , Fatores de RiscoRESUMO
BACKGROUND: The prevalence rates and influencing factors for deployment of primary prevention implantable cardioverter defibrillators (ICDs) among subjects who eventually experience sudden cardiac arrest in the general population have not been evaluated. METHODS AND RESULTS: Cases of adult sudden cardiac arrest with echocardiographic evaluation before the event were identified from the ongoing Oregon Sudden Unexpected Death Study (population approximately 1 million). Eligibility for primary ICD implantation was determined from medical records based on established guidelines. The frequency of prior primary ICD implantation in eligible subjects was evaluated, and ICD nonrecipients were characterized. Of 2093 cases (2003-2012), 448 had appropriate pre- sudden cardiac arrest left ventricular ejection fraction information available. Of these, 92 (20.5%) were eligible for primary ICD implantation, 304 (67.9%) were ineligible because of left ventricular ejection fraction >35%, and the remainder (52, 11.6%) had left ventricular ejection fraction ≤35% but were ineligible on the basis of clinical guideline criteria. Among eligible subjects, only 12 (13.0%; 95% confidence interval, 6.1%-19.9%) received a primary ICD. Compared with recipients, primary ICD nonrecipients were older (age at ejection fraction assessment, 67.1±13.6 versus 58.5±14.8 years, P=0.05), with 20% aged ≥80 years (versus 0% among recipients, P=0.11). Additionally, a subgroup (26%) had either a clinical history of dementia or were undergoing chronic dialysis. CONCLUSIONS: Only one fifth of the sudden cardiac arrest cases in the community were eligible for a primary prevention ICD before the event, but among these, a small proportion (13%) were actually implanted. Although older age and comorbidity may explain nondeployment in a subgroup of these cases, other determinants such as socioeconomic factors, health insurance, patient preference, and clinical practice patterns warrant further detailed investigation.
Assuntos
Morte Súbita Cardíaca/epidemiologia , Morte Súbita Cardíaca/prevenção & controle , Desfibriladores Implantáveis/estatística & dados numéricos , Seguro Saúde/estatística & dados numéricos , Preferência do Paciente/estatística & dados numéricos , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Comorbidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Oregon/epidemiologia , Prevenção Primária/estatística & dados numéricos , Características de Residência , Fatores de Risco , Fatores SocioeconômicosRESUMO
Sudden cardiac death (SCD) continues to be one of the leading causes of mortality worldwide, with an annual incidence estimated at 250,000-300,000 in the United States and with the vast majority occurring in the setting of coronary disease. We performed a genome-wide association meta-analysis in 1,283 SCD cases and >20,000 control individuals of European ancestry from 5 studies, with follow-up genotyping in up to 3,119 SCD cases and 11,146 controls from 11 European ancestry studies, and identify the BAZ2B locus as associated with SCD (Pâ=â1.8×10(-10)). The risk allele, while ancestral, has a frequency of ~1.4%, suggesting strong negative selection and increases risk for SCD by 1.92-fold per allele (95% CI 1.57-2.34). We also tested the role of 49 SNPs previously implicated in modulating electrocardiographic traits (QRS, QT, and RR intervals). Consistent with epidemiological studies showing increased risk of SCD with prolonged QRS/QT intervals, the interval-prolonging alleles are in aggregate associated with increased risk for SCD (Pâ=â0.006).
Assuntos
Cromossomos Humanos Par 2/genética , Morte Súbita Cardíaca , Loci Gênicos/genética , Predisposição Genética para Doença/genética , Estudo de Associação Genômica Ampla , População Branca/genética , Adulto , Idoso , Alelos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Contração Miocárdica/genética , Polimorfismo de Nucleotídeo Único/genéticaRESUMO
INTRODUCTION: Sudden cardiac death (SCD) is a large public health problem that warrants on-going evaluation in the general population. While single-year community-based studies have been performed there is a lack of studies that have extended evaluation to multiple years in the same community. METHODS AND RESULTS: From the on-going Oregon Sudden Unexpected Death Study, we analyzed prospectively identified SCD cases in Multnomah County, Ore, (population ≈700,000) from February 1, 2002 to January 31, 2005. Detailed information ascertained from multiple sources (first responders, clinical records, and medical examiner) was analyzed. A total of 1,175 SCD cases were identified (61% male) with a mean age of 65 ± 18 years for men versus 70 ± 20 for women (P < 0.001). The overall incidence rate for the period was 58/100,000 residents/year. One-quarter (24.6%) was ≤ 55 years of age. The most common initial rhythm was ventricular tachycardia or fibrillation (39% of cases, survival 27%) followed by asystole (36%, survival 0.7%) and pulseless electrical activity (23%, survival 6%). Among subjects that underwent resuscitation, the rate of survival to hospital discharge was 12% and overall survival to hospital discharge irrespective of resuscitation was 8%. Of the 68 survivors, 16 (24%) received a secondary prevention ICD. CONCLUSION: We report annualized SCD incidence from a multiple-year, multiple-source community-based study, with higher than expected rates of women and subjects age ≤ 55 years. The low implantation rate of secondary prevention ICDs is likely to be multifactorial, but there are potential implications for recalibration of the projected need for ICD implantation; larger and more detailed studies are warranted.
Assuntos
Arritmias Cardíacas/mortalidade , Arritmias Cardíacas/prevenção & controle , Morte Súbita Cardíaca/epidemiologia , Morte Súbita Cardíaca/prevenção & controle , Desfibriladores Implantáveis/estatística & dados numéricos , Prevenção Secundária/estatística & dados numéricos , Idoso , Comorbidade , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Oregon/epidemiologia , Vigilância da População , Fatores de Risco , Análise de Sobrevida , Taxa de Sobrevida , Resultado do TratamentoRESUMO
BACKGROUND: Left ventricular hypertrophy (LVH) has been associated with increased risk of sudden cardiac death (SCD), and improvements in risk stratification methodology are warranted. METHODS: We evaluated electrocardiographic intervals as potential markers of SCD risk in LVH. Corrected QT, QRS, and JT intervals were evaluated in consecutive cases with SCD and LVH from the ongoing Oregon Sudden Unexpected Death study who underwent a 12-lead electrocardiogram (EKG) and echocardiogram prior to and unrelated to the SCD event. Comparisons of age, gender, body mass index, LV ejection fraction, and EKG intervals together with clinical conditions (hypertension and diabetes) were conducted with geographically matched controls that had coronary artery disease but no history of ventricular arrhythmias or cardiac arrest. LVH was determined using the modified American Society of Echocardiography equation for LV mass. Independent samples t-test, Pearson's chi-square test, and multiple logistic regression were used for statistical comparisons. RESULTS: Of the 109 cases and 49 controls who met study criteria, age, gender, and comorbidities were similar among cases and controls. The mean LV mass index was not significantly different in cases compared to controls. However mean QTc (470.6 ± 53.6 ms vs 440.7 ± 38.7 ms; P < 0.0001) and QRS duration (113.6 ± 30.0 ms vs 104.9 ± 18.7 ms; P = 0.03) were significantly higher in cases than controls. In logistic regression analysis, prolonged QTc was the only EKG interval significantly associated with SCD (OR 1.72 [1.23-2.40]). CONCLUSION: Prolonged QTc was independently associated with SCD among subjects with LVH and merits further evaluation as a predictor of SCD in LVH.
Assuntos
Morte Súbita Cardíaca/etiologia , Eletrocardiografia , Hipertrofia Ventricular Esquerda/complicações , Hipertrofia Ventricular Esquerda/fisiopatologia , Idoso , Estudos de Casos e Controles , Comorbidade , Ecocardiografia , Feminino , Humanos , Masculino , Valor Preditivo dos Testes , Estudos Prospectivos , RiscoRESUMO
BACKGROUND: Corresponding with a continuing decline in the prevalence of sudden cardiac arrest cases presenting with ventricular fibrillation (VF), there has been a significant rise in the prevalence of pulseless electrical activity (PEA). Given significantly lower survival from PEA versus VF, we comprehensively investigated PEA correlates by incorporating first-responder data with lifetime clinical history information. METHODS AND RESULTS: In the Portland, Ore, metropolitan area (population ≈1 million), cases of out-of-hospital sudden cardiac arrest who underwent attempted resuscitation were identified prospectively (2002-2007). Those presenting with PEA versus VF and asystole were compared with χ² tests, ANOVA, and logistic regression. A total of 1277 cases aged ≥18 years underwent resuscitation by first responders (mean age, 65±16 years; 67% male). Presenting arrhythmia was VF in 48%, PEA in 25%, and asystole/other in the remainder. Compared with VF cases, PEA cases were older (mean age, 68 versus 63 years; P=0.0002), more likely to be female (37% versus 26%; P=0.0008), and less likely to survive to hospital discharge (6% versus 25%; P<0.0001). A history of syncope was strongly associated with PEA (odds ratio, 2.6; confidence interval, 1.3 to 5.3) after adjustment for age, gender, response time, and arrest circumstances. Black race was also independently associated with PEA (odds ratio, 2.6; confidence interval, 1.3 to 5.4). Pulmonary disease and female gender were significant factors associated with PEA (P for interaction=0.04). In a subgroup analysis of resting ECGs (n=391), there were no differences in cardiac clinical history or prevalence of cardiac conduction system disease (PEA, 31.6% versus VF, 32.2%; P=0.48). CONCLUSIONS: PEA cases had a significantly higher prevalence of syncope in their lifetime, with other correlates, including black race, that were distinct from VF cases. Potential mechanistic links between syncope and future manifestation with PEA warrant further exploration.
Assuntos
Morte Súbita Cardíaca/epidemiologia , Parada Cardíaca/mortalidade , Pulso Arterial/mortalidade , Síncope/mortalidade , Fibrilação Ventricular/mortalidade , Idoso , Idoso de 80 Anos ou mais , Eletrocardiografia , Feminino , Parada Cardíaca/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Oregon/epidemiologia , Prevalência , Fatores de Risco , Síncope/diagnóstico , Fibrilação Ventricular/diagnósticoRESUMO
BACKGROUND: Recent reports indicate that specific left ventricular (LV) geometric patterns predict recurrent ventricular arrhythmias in patients with implantable cardioverter-defibrillators and reduced left ventricular ejection fraction (LVEF). However, this relationship has not been evaluated among patients at risk of sudden cardiac arrest (SCA) in the general population. METHODS AND RESULTS: Adult SCA cases from the Oregon Sudden Unexpected Death Study were compared with geographic controls with no prior history of SCA. Archived echocardiograms performed closest and prior to the SCA event were reviewed. LV geometry was defined as normal (normal LV mass index [LVMI] and relative wall thickness [RWT]), concentric remodeling (normal LVMI and increased RWT), concentric hypertrophy (increased LVMI and RWT), or eccentric hypertrophy (increased LVMI and normal RWT). Analysis was restricted to those with LVEF ≤40%. A total of 246 subjects were included in the analysis. SCA cases (n=172, 68.6±13.3 years, 78% male), compared to controls (n=74, 66.8±12.1 years, 73% male), had lower LVEF (29.4±7.9% vs 30.8±6.3%, P=0.021). Fewer cases presented with normal LV geometry (30.2% vs 43.2%, P=0.048) and more with eccentric hypertrophy (40.7% vs 25.7%, P=0.025). In a multivariate model, eccentric hypertrophy was independently predictive of SCA (OR 2.15, 95% CI 1.08-4.29, P=0.03). CONCLUSIONS: Eccentric LV hypertrophy was independently associated with increased risk of SCA in subjects with EF ≤40%. These findings, now consistent between device-implanted and non-implanted populations, indicate the potential of improving SCA risk stratification from the same noninvasive echocardiogram at no additional cost.
Assuntos
Morte Súbita Cardíaca/etiologia , Ventrículos do Coração/patologia , Volume Sistólico , Idoso , Estudos de Casos e Controles , Morte Súbita Cardíaca/patologia , Ecocardiografia , Feminino , Ventrículos do Coração/diagnóstico por imagem , Humanos , Masculino , Fatores de Risco , Volume Sistólico/fisiologia , Função Ventricular EsquerdaRESUMO
BACKGROUND: Mitral valve prolapse (MVP) is relatively common in the general population with recently reported prevalence of 1% and familial clustering (Framingham Heart Study). However, its association with ventricular arrhythmias and sudden cardiac arrest (SCA) remains controversial. OBJECTIVES: The purpose of this study was to characterize the frequency and clinical profile of patients with MVP who suffer SCA in the community. METHODS: Patients with SCA cases were prospectively identified in the population-based Oregon Sudden Unexpected Death Study (population ~1 million). The presence of MVP was identified from echocardiograms recorded prior but unrelated to the SCA event. The detailed clinical profile of patients with SCA and MVP was compared with that of SCA patients without MVP to identify potential differences. RESULTS: A total of 729 SCA patients were evaluated over a 12-year period (mean age 69.5 ± 14.8 years; 64.6% men). MVP was observed in 17 (2.3%) prior to the SCA event (95% confidence interval 1.2%-3.4%). Mitral regurgitation was present in 14 SCA patients with MVP (82.3%) and was moderate or severe in 10 (58.8%). Compared with SCA patients without MVP, SCA patients with MVP were younger (mean age 60.9 ± 16.4 years vs 69.7 ± 14.7 years; P = .02), with fewer risk factors (diabetes 5.9% vs 46.4%; P = .001; hypertension 41.2% vs 78.9%; P = .001) or known coronary disease (29.4% vs 65.6%; P < .001). CONCLUSION: MVP was observed in a small proportion (2.3%) of SCA patients in the general population, suggesting a low risk overall. Since SCA patients with MVP were characterized by younger age and relatively low cardiovascular comorbidity, a focus on imaging for valve structure/insufficiency as well as genetics could aid future risk stratification approaches.
Assuntos
Morte Súbita Cardíaca , Prolapso da Valva Mitral , Valva Mitral , Adulto , Fatores Etários , Idoso , Doença da Artéria Coronariana/epidemiologia , Morte Súbita Cardíaca/epidemiologia , Morte Súbita Cardíaca/etiologia , Morte Súbita Cardíaca/prevenção & controle , Ecocardiografia/métodos , Feminino , Humanos , Hipertensão/epidemiologia , Masculino , Pessoa de Meia-Idade , Valva Mitral/diagnóstico por imagem , Valva Mitral/fisiopatologia , Insuficiência da Valva Mitral/epidemiologia , Prolapso da Valva Mitral/complicações , Prolapso da Valva Mitral/diagnóstico , Prolapso da Valva Mitral/mortalidade , Prolapso da Valva Mitral/fisiopatologia , Oregon/epidemiologia , Prevalência , Medição de Risco , Fatores de RiscoRESUMO
BACKGROUND: Repolarization abnormalities are associated with ventricular arrhythmias, and published studies report that a reversal of T wave polarity (positive or flat T wave) in lead aVR may be linked to increased cardiovascular mortality. We evaluated whether a positive or flat T wave in aVR is a risk marker for sudden cardiac death (SCD). METHODS: SCD cases from the Oregon Sudden Unexpected Death Study (catchment population ~1 million) were compared to geographic controls with coronary artery disease and no history of SCD. Archived electrocardiograms performed prior and unrelated to the SCD event were evaluated. RESULTS: SCD cases (n = 691, 67.6 ± 14.9 years, 69% male) were more likely than controls (n = 663, 66.2 ± 11.6 years, 67% male) to have diabetes (40 vs 32%; p < 0.01), left ventricular ejection fraction (LVEF) ≤35% (27 vs 11 %; p < 0.01), prolonged QTc (≥450 ms; 54 vs 28%; p < 0.01) and positive (19 vs 13%; p < 0.01) or flat T wave (14 vs 7%; p < 0.01) in aVR. On multivariable analysis, a positive/flat T wave in aVR was independently associated with SCD (OR 1.9, 95% CI 1.3-2.8, p < 0.01). However, a positive T wave alone lost statistical significance in patients with LVEF ≤ 35% and QTc ≥ 450 ms. In a subgroup analysis among patients with normal LVEF, QTc, and no diabetes, a positive T wave in aVR (but not a flat T wave) remained associated with SCD (OR 2.8, 95% CI 1.2-6.1, p < 0.01). CONCLUSIONS: A positive or flat T wave in lead aVR was associated with SCD in subsets of patients. This simple ECG marker in this often-ignored lead may contribute to enhancement of SCD risk stratification, and warrants further evaluation.
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Arritmias Cardíacas/mortalidade , Morte Súbita Cardíaca/epidemiologia , Eletrocardiografia/métodos , Eletrocardiografia/estatística & dados numéricos , Disfunção Ventricular Esquerda/mortalidade , Idoso , Arritmias Cardíacas/diagnóstico , Comorbidade , Feminino , Humanos , Incidência , Masculino , Oregon/epidemiologia , Fatores de Risco , Distribuição por Sexo , Taxa de Sobrevida , Disfunção Ventricular Esquerda/diagnósticoRESUMO
BACKGROUND: Prolongation of initial ventricular depolarization on the 12-lead electrocardiogram (ECG), or delayed intrinsicoid deflection (DID), can indicate left ventricular hypertrophy (LVH). The possibility that this marker could convey distinct risk of sudden cardiac arrest (SCA) has not been evaluated. OBJECTIVE: To evaluate the association of DID and SCA in the community. METHODS: In the ongoing prospective, population-based Oregon Sudden Unexpected Death Study (Oregon SUDS; catchment area approximately 1 million), SCA cases were compared to geographic controls with no SCA. Archived ECGs (closest and unrelated to SCA event for cases) were evaluated for the presence of DID, defined as ≥0.05 second in leads V5 or V6. Left ventricular (LV) mass and function were evaluated from archived echocardiograms. RESULTS: SCA cases (n = 272, 68.7 ± 14.6 years, 63.6% male) as compared to controls (n = 351, 67.6 ± 11.4 years, 63.3% male) were more likely to have DID on ECG (28.3% vs. 17.1%, P = .001). DID was associated with increased SCA odds (odds ratio [OR] 1.92; 95% confidence interval [CI] 1.31-2.81; P = .001), but showed poor correlation with LV mass and echocardiographic LVH (kappa 0.13). In multivariate analysis adjusted for clinical and ECG markers, reduced LV ejection fraction, and echocardiographic LVH, DID remained an independent predictor of SCA (OR 1.82; 95% CI 1.12-2.97; P = .016). Additionally, in a sensitivity analysis restricted to narrow QRS, DID and ECG LVH by voltage were each independently associated with SCA risk. CONCLUSION: DID was associated with increased SCA risk independent of echocardiographic LVH, ECG LVH, and reduced LV ejection fraction, potentially reflecting unique electrical remodeling that warrants further investigation.
Assuntos
Morte Súbita Cardíaca/etiologia , Eletrocardiografia , Hipertrofia Ventricular Esquerda/fisiopatologia , Função Ventricular Esquerda/fisiologia , Idoso , Morte Súbita Cardíaca/epidemiologia , Feminino , Seguimentos , Humanos , Hipertrofia Ventricular Esquerda/complicações , Incidência , Masculino , Razão de Chances , Oregon/epidemiologia , Prognóstico , Estudos Prospectivos , Taxa de Sobrevida/tendências , Fatores de TempoRESUMO
OBJECTIVES: To assess potential improvement in SCD risk prediction by adding selected risk markers from the 12-lead ECG to measurement of the left ventricular ejection fraction (LVEF). BACKGROUND: Novel strategies to improve risk stratification for sudden cardiac death (SCD) are needed. Given the modest odds associated with most individual risk markers, combining multiple markers may be a useful approach. METHODS: From the ongoing Oregon Sudden Unexpected Death Study, SCD cases with pre-event LVEF available were compared to matched control subjects with coronary artery disease. Resting heart rate, QRS duration (QRSD), and JTc intervals were measured from archived ECGs prior and unrelated to the SCD event. Independent odds of SCD for individual and combined ECG markers were calculated. RESULTS: SCD cases (n= 317; 67.9 ± 12.9 years) were more likely than controls (n=317; 67.9 ± 12.8 years) to have LVEF ≤ 35% (26% vs. 11%). Mean heart rate, QRSD, and JTc were significantly higher in cases (all p<0.0001). In adjusted analyses, higher heart rate [OR 2.6 (1.8 - 3.7)], QRSD [OR 1.5 (1.0 - 2.5)] and JTc [OR 2.3 (1.6 - 3.4)] were independently associated with SCD. When ECG markers were combined, SCD odds progressively increased with one [OR 3.4 (2.1 - 5.4)] and ≥ 2 elevated markers [OR 6.3 (3.3 - 12.1)]. Addition of ECG markers to an adjusted model with LVEF improved discrimination (C statistic 0.724 vs. 0.642) and net reclassification (by 22.7%) (p<0.0001). CONCLUSIONS: Combining selected 12-lead ECG markers with LVEF improves SCD risk prediction, and warrants further investigation in prospective studies.
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OBJECTIVE: Work environment is said to influence cardiovascular risk. We assessed whether nature of occupation affects risk of sudden cardiac death (SCD) in the general population. METHODS: In the ongoing, prospective Oregon Sudden Unexpected Death Study (catchment population 1 million), working-age SCD cases (18-65 years) were compared with controls who died from any cause. Usual occupation obtained from death certificates was classified using the US Census Bureau standard occupational classification descriptions and categorised as white collar, blue collar or homemaker. Odds ratio (OR) for SCD by occupation category was obtained and clinical profile of SCD cases was compared by occupation type. RESULTS: Among SCD cases (n=646; 74% male) compared to controls (n=622; 73.6% male), the proportion of white collar workers was higher among male SCD cases (52.7% vs 43.7%; p=0.01); the difference in females was smaller (59.5% vs 55%; p=0.62). Adjusting for race and smoking status, male white collar workers had a higher risk of SCD compared to blue collar workers (OR=1.67, (1.26 to 2.23), p<0.001). A similar, non-significant trend was observed among females (OR 1.49 (0.81 to 2.75); p=0.20). White collar SCD cases were less likely to be current smokers (34.7% vs 45.3%, p=0.008), drug misusers (13.1% vs 18.5%) or have diabetes (21.4% vs 28.2%, both p=0.07) compared to blue collar workers. Other cardiac risk factors were similar. CONCLUSIONS: A white collar occupation was associated with increased risk of SCD, when compared to blue collar occupations. Since differences in conventional risk factors did not explain this elevated risk, work-related behavioural and psychosocial stressors warrant a closer evaluation.
Assuntos
Morte Súbita Cardíaca/etiologia , Ocupações , Características de Residência , Trabalho , Adulto , Estudos de Casos e Controles , Diabetes Mellitus/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ocupações/classificação , Razão de Chances , Oregon/epidemiologia , Estudos Prospectivos , Fatores de Risco , Fumar/epidemiologia , Estresse Psicológico , Transtornos Relacionados ao Uso de Substâncias/epidemiologiaRESUMO
OBJECTIVES: The purpose of this study was to determine whether chronic obstructive pulmonary disease (COPD) is associated with sudden cardiac death (SCD) in the community. BACKGROUND: COPD is linked to cardiovascular mortality; an association with SCD has not been systematically investigated in the general population. METHODS: In the Oregon Sudden Unexpected Death Study (approximately 1 million population), adult SCD case subjects were compared with geographic control subjects with coronary artery disease. Detailed clinical and electrocardiographic risk marker information was obtained from medical records. The association of COPD with SCD in the overall population and in a propensity score-matched dataset was assessed with logistic models. RESULTS: SCD case subjects (n = 728; age 69.9 ± 13.7 years) were more likely than control subjects (n = 548; age 67.2 ± 11.3 years) to have left ventricular ejection fraction ≤35% (27.5% vs. 12.0%; p < 0.0001), COPD (30.8% vs. 12.8%, p < 0.0001), diabetes mellitus (47.7% vs. 31.8%; p < 0.0001), use short-acting beta-2 agonist agents (SBAs) (22.3% vs. 12.6%; p < 0.0001), and less likely to use beta-blockers (60.6% vs. 66.4%; p = 0.03). In multivariable analysis, COPD was significantly associated with SCD (odds ratio [OR]: 2.2; 95% confidence interval [CI]: 1.4 to 3.5; p < 0.001). There was no significant interaction between COPD and medications, but an interaction was identified between SBAs and beta-blockers (p = 0.04); SBAs were strongly associated with SCD in subjects not taking beta-blockers (OR: 3.3; 95% CI: 1.4 to 7.7; p = 0.005) but not in those taking beta-blockers (OR: 1.3; 95% CI: 0.7 to 2.3; p = 0.39). The COPD-SCD association was maintained in a propensity score-matched analysis. CONCLUSIONS: COPD is associated with SCD risk in the community independent of medications, electrocardiographic risk markers, and left ventricular ejection fraction. Among other mechanisms, pro-arrhythmogenic right ventricular remodeling and systemic inflammation warrant further investigation.
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BACKGROUND: Obesity has been associated with significantly greater risk of sudden cardiac death (SCD); however, identifying the obese patient at highest risk remains a challenge. We evaluated the association between QRS fragmentation on the 12-lead electrocardiogram and SCD, in obese/overweight subjects. METHODS AND RESULTS: In the ongoing prospective, community-based Oregon Sudden Unexpected Death Study (population approximately 1 million), we performed a case-control analysis, comparing obese/overweight SCD victims with obese/overweight controls from the same geographic region. Archived ECGs prior and unrelated to the SCD event were used for cases and all ECG measurements were assessed in blinded fashion. Fragmentation was defined as the presence of RSR' patterns and/or notching of the R/S wave in at least 2 contiguous leads. Analysis was limited to ECGs with QRS duration <120 ms. Overall prevalence of fragmentation was higher in cases (n=185; 64.9±13.8 years; 67.0% male) compared with controls (n=405; 64.9±11.0 years; 64.7% male) (34.6% versus 26.9%, P=0.06). Lateral fragmentation was significantly more frequent in cases (8.1% versus 2.5%; P<0. 01), with non-significant differences in anterior and inferior territories. Fragmentation in multiple territories (≥2) was also more likely to be observed in cases (9.7% versus 4.9%, P=0.02). In multivariable analysis with consideration of established SCD risk factors, lateral fragmentation was significantly associated with SCD (OR 2.84; 95% CI 1.01 to 8.02; P=0.05). CONCLUSION: QRS fragmentation, especially in the lateral territory is a potential risk marker for SCD independent of the ejection fraction, among obese/overweight subjects in the general population.