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Sudden Cardiac Arrest Sudden Cardiac Arrest Prepared for [Referring MD Group] [Insert Presentation Date] 

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  • Sudden Cardiac ArrestPrepared for [Referring MD Group][Insert Presentation Date]

  • Sudden Cardiac Arrest (SCA)SCA claims an estimated 325,000 lives each year1,000 lives every day, one life every two minutesSCA accounts for half of all cardiac-related deathsOver half of SCA victims have no prior symptomsSurvival requires emergency medical intervention and defibrillation within the first minutes following arrestThe survival rate is as high as 90 percent if treatment is initiated within the first minutes following arrestAn estimated 95 percent of SCA victims die before they reach a hospital or other source of emergency help

  • Sudden Cardiac Arrest (SCA)85-90 percent of SCAs are actually the first arrhythmic event a patient experiencesDeath from SCA can frequently be predicted and prevented by identifying individuals at high risk and intervening

  • What Causes SCA?Ventricular tachycardia Ventricular fibrillation Hypertrophic cardiomyopathyInherited and acquired electrical diseases, e.g. Long QT syndromes Congenital anomalous coronary arteryReduced Ejection Fraction

  • Sudden Cardiac Arrest

  • Impact of Sudden Cardiac ArrestMore people die from Sudden Cardiac Arrest than from AIDS, Breast Cancer and Lung Cancer combinedHeart Rhythm Society 2005; American Cancer Society 2005, CDC 2003 Est.

  • Urgency of Sudden Cardiac ArrestResuscitation Success vs. Time

    % % SuccessSuccess*Non*Non--linearlinearAdapted from text: Cummins RO, Annals Emerg Med. 1989, 18:1269-1275.Chance of success reduced 7-10% each minute

  • Risk FactorsHigh-risk patient populations have been identified:Prior Sudden Cardiac ArrestPrior Myocardial Infarction Heart Failure (Class II to IV)Ejection Fraction less than 40%Family History of Sudden Cardiac Arrest

  • Risk FactorsAdditional risk factors include:Recurrent unexplained syncopeIdiopathic cardiomyopathy with syncope or VTHypertrophic cardiomyopathy with syncope or VTRight ventricular dysplasiaLong-QT syndrome

  • SCA and Coronary Heart DiseaseAn estimated 13 million people had CHD in the U.S. in 20021Sudden death was the first manifestation of coronary heart disease in 50% of men and 63% of women1CHD accounts for at least 80% of sudden cardiac deaths in Western cultures3* ion-channel abnormalities, valvular or congenital heart disease, other causes1 American Heart Association. Heart Disease and Stroke Statistics2003 Update. Dallas, Tex.: American Heart Association; 2002.2 Adapted from Heikki et al. N Engl J Med, Vol. 345, No. 20, 2001.3 Myerberg RJ. Heart Disease, A Textbook of Cardiovascular Medicine. 6th ed. P. 895.Etiology of Sudden Cardiac Death2,3

  • SCA and Heart FailureIn people diagnosed with CHF, sudden cardiac death occurs at 6-9 times the rate of the general population1CHF significantly increased sudden death and overall mortality in both men and women21 American Heart Association. Heart and Stroke Statistical 2003 Update. Dallas, Tex.: American Heart Association: 2002. 2 Redrawn from Kannel WB, Wilson PWF, D'Agostino RB, Cobb J. Sudden coronary death in women. Am Heart J 1998 Aug; 136: 205-2123 Framingham Heart Study (1948 1988) in Atlas of Heart Diseases.4 American Heart Association. Heart Disease and Stroke Statistics2003 Update

  • SCA and Myocardial InfarctionThe prevalence of Myocardial Infarction (MI) in the U.S. in 2002 was 7.6 million1MIs are identified in as many as 50-75% of sudden cardiac arrest victims2,3,4Within 6 years of a recognized MI, 7% of men and 6% of women will experience sudden death1Individuals with a prior MI have a sudden death rate 4-6 times that of the general population11 American Heart Association. Heart Disease and Stroke Statistics2003 Update. Dallas, Tex.: American Heart Association; 2002.2 Myerberg RJ. Heart Disease, A Textbook of Cardiovascular Medicine. 6th ed. Philadelphia: WB Saunders Co; 1997:chapter 24. 3 Lombardi G. JAMA. 1994;271:678-683.4 Bigger JT. Circulation. 1984;69:250-258.

  • Ejection FractionReduced left ventricular ejection fraction (LVEF) remains the single most important risk factor for overall mortality and sudden cardiac death1Post-MI patients with LV dysfunction (< 40%) have a sudden death rate thats similar to a CHF population1 Prior SG, Aliot E, Blonstrom-Lundqvist C, et al. Task Force on Sudden Cardiac Death of the European Society of Cardiology. Eur Heart J, Vol. 22; 16; August 2001.2 Vreede-Swagemakers JJ. J Am Coll Cardiol. 1997;30:1500-1505.LVEF and SCA Incidence2

  • TreatmentRisk Factor Modification Healthy dietRegular exerciseWeight lossSmoking cessationMedical TherapyBeta blockersACE inhibitorsLipid therapyInterventional ProceduresImplantable cardioverter defibrillator (ICD)Revascularization

  • Medical TherapyGeneral MeasuresRBP
  • ACE InhibitorsPatients with a history of coronary artery disease, stroke, or peripheral vascular disease, or diabetes plus one other cardiovascular risk factorPatients at high risk for heart attack or stroke can reduce the risk of sudden cardiac arrest by 21% by taking ACE inhibitors

    Heart Outcomes Prevention Evaluation Study Investigators N Engl J Med. 2000 Jan 20;342(3):145-53.

  • Beta BlockersBeta blockers can reduce the risk of sudden cardiac arrest by up to 50% and overall risk of death by 25-40%CIBIS-II Investigators, Lancet, 353: 9, 1999

  • Effect of Spironolactone on Morbidity and MortalityPitt et al, N Engl J Med, 341: 709, 1999

  • Lipid Lowering TherapiesStatins have consistently shown the greatest benefits in patients with low HDL-C and average LDL (CARE, LIPID,AFCAPS/TexCAPS) or high LDL-C 94S, WOSCOPS)Fibrates have shown benefits in patients with:- High triglycerides and low HDL-C (Helsinki)- Normal LDL-C and low HDL-C (VA-HIT)

  • ICD TherapyFirst-line therapy for ventricular tachycardia (VT)/ ventricular fibrillation (VF) patientsTransvenous, single incisionLocal anesthesia; conscious sedationShort hospital stayPerioperative mortality < 1%Programmable therapy optionsSingle- or dual-chamber therapyBattery longevity up to 7 yearsMore than 100,000 implants/year

  • ICD Therapy

  • ICD Trials: MADIT INearly 200 patients randomized to ICD or conventional medical therapy over 63 monthsPrior MILVEF 35%Inducible/nonsuppressible sustained VT andAsymptomatic NSVT (330 beats)ICD therapy reduced total mortality by 54% ICD therapy reduced arrhythmic mortality by 74%Trial stopped early due to significantly superior survival for ICD patients

  • ICD Trials: MADIT IIOver 1,200 patients randomized to ICD or conventional medical therapy Coronary artery diseaseMI 30 days priorLVEF 30%EP studies results consideredICD therapy reduced total mortality by 31%Subsequent analysis shows risk of SCA in this population does not decrease over time

  • ICD Trials: MADIT IIMoss et al. New Engl J Med. 2002; 346 (12): 877

  • ICD Trials: MUSTTOver 1,250 registry patients followed over 60 months to evaluate the efficacy of anti-arrhythmic therapy guided by electrophysiology (EP) studies Coronary artery disease Asymptomatic or minimally symptomatic NSVT LVEF 40%ICD therapy reduced overall mortality by 55-60%EP-guided therapy provided no survival benefit

  • ICD Trials: MUSTTBuxton, et al. New Engl J Med. 1999; 341: 1882-90.

  • ICD Trials: SCD-HeFTLargest ICD trial to date following 2,500 patients in 150 center with 2 year follow-upSymptomatic CHF (NYHA class II and III) due to ischemic or nonischemic dilated cardiomyopathyCHF 3 monthsLVEF 35%ACE I and Beta Blocker therapy if toleratedICD therapy reduced overall mortality by 23% in patients with moderate heart failure

  • ICD Trials: SCD-HeFTBardy et al. , et al. New Engl J Med. 352 (3): 225, Figure 1

  • ICD Trials: DEFINITEFirst trial to study ICD therapy as primary prevention in non-ischemic patientsMild to moderate heart failureLVEF < 35%450 patients randomized to conventional medical therapy (CMT) or CMT plus ICD At two years, ICD group showed mortality of 8% compared with mortality of nearly 14% in the CMT group

  • ICD Trials: COMPANIONLargest heart failure trial to date following over 1,500 chronic CHF patients at 128 centers CHF (NYHA class III or IV) CHF-related hospitalization within 12 monthsQRS width of 120 ms due to ischemic or nonischemic cardiomyopathyPatients were randomized to:20% received OPT (optimal pharmacologic therapy) alone 40% received OPT plus CRT-P (device with pacing stimulation) 40% received OPT plus CRT-D (device with defibrillation)OPT plus CRT-D reduced overall mortality by 36%

  • Trial ImplicationsRecent clinical trials have shown ICDs to be effective in a variety of patient populationsMedicare has recently expanded coverage of ICD placement for up to 500,000 individualsCriteria for coverage include specific history of:CardiomyopathyPrevious heart attackHeart failureLow Ejection Fraction (< 35%)Medicare coverage for an ICD is approximately $30,000

  • SummarySCA is leading cause of death and can frequently be predicted and preventedIndividuals with a prior SCA event, prior MI or heart failure are at risk for SCAEjection Fraction is a key indicator of risk level for SCA. EF less than 40% warrants further cardiac evaluationMedical therapies (Beta Blockers, ACE Inhibitors and Lipid therapy) have been effective in reducing the risk of SCAA series of clinical trials have demonstrated the effectiveness of ICD therapy in a variety of patient populations