Sudden Cardiac Death: Definitions

Transcription

1 Contemporary Epidemiology of Sudden Death: Insights from the Comprehensive UCSF SCD Study 23 October 2010 Update in Electrocardiography and Arrhythmias Zian H. Tseng, M.D., M.A.S. Assistant Professor of Medicine Electrophysiology Section University of California, San Francisco Disclosures Major Research grant: NIH K12 RR Research grant: NIH/NHLBI R01 HL Minor Biotronik: Honorarium St. Jude Medical: Honorarium Sudden Death: Background 1/3 of SCA events are unwitnessed Impossible to restrict the definition of SCA to documented VF since rhythm at clinical presentation is unknown in many cases Operational criteria for SCA and SCD do not rely upon the cardiac rhythm at the time of the event Duration of symptoms (< 1 hr) prior to SCA generally defines the suddenness of death 1

2 Sudden Death: Definitions Out-of-hospital occurrence of a presumed sudden pulseless condition in the absence of evidence of a noncardiac condition (e.g., pulmonary, CVA, PE) as the cause of collapse WHO definition of SCD: Unexpected death within 1 h of symptom onset if witnessed Unexpected death within 24 h of having been observed alive and sx-free if unwitnessed Magnitude of Sudden Death in the U.S. 1 U.S. Census Bureau, Statistical Abstract of the United States: American Cancer Society, Inc., Surveillance Research, Cancer Facts and Figures Heart and Stroke Statistical Update, American Heart Association. 4 Circulation. 2001;104: SCD Rates in the Developed World 2

3 Etiology of Sudden Death Huikuri et al. N Engl J Med, Vol Surveillance of SCD in San Francisco County San Francisco County: 2007 population 756,976 Median age 36.5 years 49% female: 51% male 31% Asian, 8% Black, 44% Caucasian, 14% Hispanic/Latino By California state law, all out-of-hospital have to be reported to ME All cases without an attending physician willing or able to determine cause of death (i.e. ER deaths) are reported to ME Retrospective review of all ME death records for deaths meeting WHO SCD definition to determine incidence of SCD in 2007 Cases were excluded if : known history of non-cardiac chronic and/or terminal illness identifiable non-cardiac etiology at time of death (e.g., obvious recent drug use). Retrospective Review of all ME Deaths, SF 2007 Review of details of presentacon at death All SF ME Deaths N= 1420 WHO SCDs N=262 Tseng ZH, et al AHA Scientific Sessions

4 WHO SCDs in San Francisco County, 2007 Between January 1, 2007 and December 31, 2007: 262 cases of WHO SCD Incidence of 34.6 per 100,000 Previous estimates in homogeneous populations: /100,000 Mean age 61.3 years 30% female: 70% male 4.3% of overall mortality in San Francisco County 2007 SCD Rates in San Francisco County by Ethnicity Determination of Actual Sudden Arrhythmic Deaths How specific are WHO SCD criteria for actual arrhythmic sudden death? Panel of 3 physicians For each WHO SCD: review of all post-mortem ME investigations (prior hospital records, autopsy, toxicology, histology) Final cause of death adjudicated as Noncardiac (e.g. PE, CVA) non-arrhythmic sudden death (e.g., CHF, tamponade) sudden arrhythmic death 4

5 Determination of Sudden Arrhythmic Deaths Review of details of presentacon at death Review of full ME invescgacon (records, autopsy, toxicology) All SF ME Deaths N= 1420 WHO SCDs N=262 N=158 (60.3%) Non- N=104 (39.7%) Sudden Arrhythmic Death N=147 (56% of WHO SCDs) Non- Arrhythmic Sudden Death N=11 Tseng ZH, et al AHA Scientific Sessions 2009 Sudden Arrhythmic Death in San Francisco etiology accounted for 158 of 262 WHOdefined SCDs representing a rate of 20.9 per 100,000 Accuracy of WHO criteria for true cardiac etiology = 60.3% Accuracy of WHO criteria for arrhythmic etiology = 56.1% Most common non-cardiac causes of SCD were lethal drug or alcohol overdose, pulmonary disease, and cancer. Low PPV for True SAD WHO SCD SAD Cases Incidence (per 100,000) Mean Age Percent Male Overall Mortality (2007) 69.9% 70.1% 4.3% 2.4% Number of Cases WHO SCD v. SAD WHO SCD SAD PPV of WHO SCD criteria for true SAD = 56.1% Tseng ZH, et al AHA Scientific Sessions

6 140 SCD Rates in San Francisco, 2007 Rates of SCD per 100, SF 2007 WHO SCD SF 2007 SAD Chugh et al. (2004) de Vreede- Swagemakers Low Rate Becker et al. et al. (1997) (1993) High Rate Becker et al. (1993) 1. Chugh SS, Jui J, Gunson K, Stecker EC, John BT, Thompson B, Ilias N, Vickers C, Dogra V, Daya M, Kron J, Zheng ZJ, Mensah G, McAnulty J. Current burden of sudden cardiac death: mulcple source surveillance versus retrospeccve death cercficate- based review in a large U.S. community. J Am Coll Cardiol. 2004;44(6): de Vreede- Swagemakers JJ, Gorgels AP, Dubois- Arbouw WI, van Ree JW, et al. Out- of- hospital cardiac arrest in the 1990s " a populacon- based study in the Maastricht area on incidence, characterisccs and survival. J Am Coll Cardiol 1997;30(6): Becker, LB, Smith DW, Rhodes KV. Incidence of cardiac arrest: a neglected factor in evaluacng survival rates. Ann Emerg Med 1993;22(1): Tseng ZH et al AHA 2009 SCD/SAD Rates Vary Widely by Ethnicity and Sex Tseng ZH, et al AHA Scientific Sessions 2009 Sudden Arrhythmic Deaths vs. Control (Trauma) Deaths SF ME Deaths N=1420 WHO SCDs N=262 N=158 Non- N=104 Accidental Trauma deaths N=376 Autopsy N=238 Arrhythmic N=147 Non-arrhythmic N=11 Autopsy N=47 6

7 CAD in SADs vs. Controls Significant CAD was present in 39% of SADs and associated with higher SAD risk compared to control deaths (OR 2.58, 95% CI , p=0.026). Only 1 of 37 (2.7%) SADs and 0 of 192 controls had an active coronary lesion, p = 0.17 Interstitial Fibrosis in SADs vs. Trauma Controls 40x LV septum, trichrome stain 77yo AM trauma victim, minimal CAD 77yo AM SAD victim, minimal CAD Global interstitial fibrosis score 1.5-fold higher in SADs than controls, adjusted for age, sex, ethnicity, CAD level Epidemiologic Insights Thus Far WHO SCD criteria have a low PPV for SAD Blacks have 2.4-fold higher incidence of SAD than Caucasians Men have 2.3-fold higher incidence than women Active coronary lesion as the cause of SAD is far lower than previous estimates Significant CAD accounted for less than 40% of SADs, half of historical estimates Significant CAD still imparts a 2.5-fold higher risk of SAD Interstitial myocardial fibrosis is associated with SAD and may serve a useful risk stratifier Reflects contemporary epidemiology of SAD and CAD in a diverse community 7

8 Magnitude of Sudden Death in the U.S. 1 U.S. Census Bureau, Statistical Abstract of the United States: American Cancer Society, Inc., Surveillance Research, Cancer Facts and Figures Heart and Stroke Statistical Update, American Heart Association. 4 Circulation. 2001;104: Etiology of Sudden Death Adapted from Huikuri et al. N Engl J Med, Vol Sudden Arrhythmic Deaths vs. Control (Trauma) Deaths SF ME Deaths N=1420 WHO SCDs N=262 N=158 Non- N=104 Accidental Trauma deaths N=376 Autopsy N=238 Arrhythmic N=147 Non-arrhythmic N=11 Autopsy N=47 8

9 Comprehensive UCSF SCD Study 5 year study, collaboration with SF County ME 3 years of systematic autopsy evaluation of SCD compared to frequency-matched trauma controls Evaluation of morphometric parameters Heart weight LV septal thickness MV prolapse Evaluation of myocardial fibrosis Creation of DNA and cardiac tissue bank for future high-quality genetic and molecular studies Derive more accurate definition of SCD Inform policy for investigation of SCDs by MEs Acknowledgements UCSF EP Section Jeff Olgin Dan Steinhaus Dean Whiteman UCSF Epidemiology Stephen Hulley Eric Vittinghoff Feng Lin UCSF Program in Human Genetics Brad Aouizerat Ludmila Pawlikowska Annie Poon UCSF Genomic Resource in Atherosclerosis John Kane Mary Malloy Clive Pullinger SFFD/ SFGH Emergency Medicine Karl Sporer SF Medical Examiner s Office Ellen Moffatt Amy Hart UCSF Pathology Phil Ursell 9