Sudden Cardiac Death Yong Hoon Kim M D

Sudden Cardiac Death Yong Hoon Kim, M. D. , Ph. D. Division of Cardiology, Department of Internal Medicine, School of Medicine, Kangwon National University

Definition of SCD n The unexpected natural death from a cardiac cause heralded by abrupt loss of consciousness within a short time period, generally less than 1 hour from the onset of symptoms. n Preexisting heart disease may or may not have been known to be present, but the time and mode of death are unexpected. Pinto DS et al. The Heart. 2001: 1015 -1048

Definition of SCD n Any cardiac death occuring out of the hospital or taking place in the emergency room or dead on arrival in the emergency room. Gillum RF et al. Circulation 1989; 79: 756 -765

Time References in SCD A Prodromes B Onset of terminal event C Cardiac arrest D Biological death New or worsening Abrupt change in Sudden Failure of cardiovascular clinical status: Collapse resuscitation ---------- Or Arrhythmias Loss of Failure of Chest pain Hypotension effective electrical, Palpitations Chest pain circulation mechanical, or Dyspnea Weakness Light headedness symptoms Days to months CNS function Loss of after initial consciousness resuscitation Instantaneous to 1 h Minutes to weeks

Epidemiology § In the World, 3, 000 SCD/year Survival rate < 1% § In USA, 250, 000 to 400, 000 SCD/year Survival rate 5% § Unfortunately, SCD is first presentation of cardiac disease in 33%~50% of patients Mark Josphson et al. Circulation. 2004; 109: 2685 -2691

Magnitude of SCA in the U. S # deaths/year Mark Josphson et al. Circulation. 2004; 109: 2685 -2691

Epidemiology In Korea, > 20, 000 SCD/year → > 41/100, 000 (2005~2006) 돌연사의 약 3/4이 집에서 발생 돌연사의 약 2/3 가 목격자가 있다.

The Incidence of SCD in Specific Populations in U. S. A. Group General population 0. 1~0. 2%/year 300, 000/year Pts with high coronaryrisk profile Pts with previous coronary event Pts with ejection fraction<35%, congestive heart failure Pts with previous out-ofhospital cardiac arrest Pts with previous myocardial infarction, low ejection fraction, and ventricular tachycardia Incidence of Sudden Death (% of group) No. of Sudden Deaths per Year

The Incidence of SCD n Age : two ages of peak incidence 1) birth ~ 6 months of age (the sudden infant death syndrome) 2) 45 ~ 75 years of age n Heredity : congenital long QT interval syndromes hypertrophic cardiomyopathy right ventricular dysplasia Brugada syndrome

The Incidence of SCD n Gender : huge preponderance in males compared with females because of the protection females before menopause M: 3. 8 -fold excess incidence of sudden coronary death Kannel WB et al. The Franingham study. 1982

Mechanisms of SCD ANATOMIC /FUNCTIONAL SUBSTRATE CAD Cardiomyopathy Right ventricular dysplasia Valvular Congenital Primary electrophysiological Neurohormonal Asystole Developmental VT Inflammatory Infiltrative VF Reentry Automaticity Triggered activity Block Cell-to-cell uncoupling ARRHYTHMIA MECHANISMS Neuro/endocrine Drugs Electrolytes, p. H, p. O 2 Ischemic/reperfusion Hemodynamic Stretch Arising/Stress/Sleep TRANSIENT INITIATING EVENTS Venn Diagram showing Interaction of Various factors

Causes of SCD Acute Mechanical Causes : 5% Coronary Artery Disease : 75~80% Non-structural Heart Disease : 5~10% Structural Heart Disease : 10~15%

VHD 5% Normal 3% Other DCM 10% CAD 80% Spasm Long QT CAD 42% Normal 9% VHD Men Other 22% Women DCM 18% HCM 26% CAD 3% Coronary anomaly 14% Commtion cordis 20% Young Athletes

Progression of atheromatous plaque

Coronary Artery Disease -1 n Coronary atherosclerosis Acute myocardiacl infarction Chronic ischemic heart disease with transient supply-demand imbalnace – thrombosis, spasm. physical stress n Congenital abnormailties of coronary arteries Anomalous origin from pulmonary arteries Other coronary arteriovenous fistular Origin of right coronary artery from left sinus of Valsalva Hypoplastic or aplastic coronary arteries Coronary-intracardiac shunt

Coronary Artery Disease -2 n Coronary artery embolism n Coronary artetitis PAN, progressive systemic sclerosis, giant cell arteritis Mucocutaneous lymph node syndrome (Kawasaki disease) Syphilitic coronary ostial stenosis n Micellaneous mechanical obstruction of coronary a. Coronary artery dissection n Functional obstruction of coronary arteries Coronary artery spasm Myocardial bridge

Myocardial disease and heart failure n Chronic congestive heart failure Ischemic cardiomyopathy Idiopathic congestive cardiomyopathy Alcoholic cardiomyopathy Hypertensive cardiomyopathy Post-myocarditis cardiomyopathy Postpartum cardiomyopathy n Acute cardiac failure Massive acute myocardial infarction Acute myocarditis

Inflammatory, Infiltrative, Neoplastic and Degenerative process § Viral myocarditis § Sarcoidosis § Progressive systemic sclerosis § Amyloidosis § Hemochromatosis § Idiopathic giant cell myocarditis § Chaga’s disease § Cardiac gangilonitis § Arrhythmogenic right ventricular dysplasia (ARVD) § Neuromuscular disease

Non-structural Heart Disease n Long QT syndrome Congenital long QT syndrome Acquired long QT syndrome : Drug effect, Electolyte abnormality, Toxic Substance Hypothemia, CNS injury n Brugada syndrome n Sudden unexplained death syndrome of Southeast Asia (SUDS) n Familial sudden death syndrome n Primary ventricular fibrillation n WPW syndrome (rapid antidromic conduction) n Severe electrolyte abnormalities

Acute Mechanical Causes n Aortic rupture n Ventricular rupture n Commotio cordis – blunt chest trauma • Fatal cardiac arrest without detectable structural damage to the heart as a result of blunt impact to chest • various mechanism : V-fib etc.

Specific dieases and SCD

Ventricular Hypertrophy n Independent risk factor for SCD contributing to mechanisms of potentially lethal arrhythmias Anderson KP. J Cardiovasc Pharmacol, 1984 n Underlying conditions - Hypertensive heart disease - HCMP with or without obstruction - Primary pulmonary HTN with RV hypertrophy - RV overload d/t congenital heart disease

Transverse section through Ventricles Normal Cardiac Crosssection Hypertrophied Cardiac Cross-section

Hypertrophic CMP n Prevalence : - 0. 2% in young adult 2 -4% SCD in adult & 4 -6% in adolescent - SCD : 67% of 48 deaths (n=254, 6 YF/U) Br Heart J, 1982; 48: 1 55% of 49 deaths (n=190) Circ Res, 1974; (S 2)35: 179 - SCD as 1 st clinical manifestation n Gene mutation - the genes that encode the cardiac muscle sarcomere ( -tropomyosin & -myosin heavy chain mutation ) n Mechanism : Unclear - arrhythmia, ischemia - abrupt hemodynamic change

Risk factors for SCD in Patients with HCMP n Major risk factors Cardiac arrest (ventricular fibrillation) Spontaneous sustained ventricular tachycardia Family history of sudden death ( sudden death from hyperthrophic cardiomyopathy in two or more first-degree relatives younger than 40 years of age ) Rick A. Nishimura et al. NEJM 2004; 350: 1320 -7

n Minor risk factors Unexplained syncope (two or more episodes of syncope within one year) Left ventricular wall thickness > 30 mm Abnormal blood pressure on exercise (rise more than 25 mm. Hg from baseline or decrease of more than 10 mm. Hg from maximal pressure during exercise) Nonsustained ventricular tachycardia Left ventricular outflow obstruction Microvascular obstruction (on nuclear imaging or MRI ) High-risk genetic defect Rick A. Nishimura et al. NEJM 2004; 350: 1320 -7

A high risk ! (HCMP) ( warranting prophylactic implantation of an automatic defibrillator) ≥ 1 major risk factors or ≥ 3 minor risk factors. Rick A. Nishimura et al. NEJM 2004; 350: 1320 -7

Valvular Heart Disease n Aortic Stenosis : - one of common causes of SCD before valve surgery era - after AVR : still at risk for SCD arrhythmias, valve dysfunction, CAD - 21% of 298 post-op deaths (peak : 3 rd week, plateau : after 8 months ) Circulation 1985; 72: 753

Dissected Heart showing Valve Openings Rheumatic MS

Congenital Heart Disease n SCD by arrhythmia : 4 congenital conditions - Tetralogy of Fallot - Transposition of the great arteries - Aortic stenosis - Pulmonic obstruction Zipes DP et al. Circulation. 1998; 98: 2334 -2351

SCD without structural heart disease - solely “electrical” basis n Wolff-Parkinson-White syndrome n Long QT syndrome n The Brugada syndrome n Short-coupled torsade de pointes n Cathecholamine- induced polymorphic ventricular tachyarrythmia n Idiopathic VF Eric F. D. Wever et al. JACC. 2004; 43: 1137 -1144.

Strategies for Prevention of SCD n Effective treatment in patients at high risk with previously documented episodes of SCD n Identification of high-risk populations before an episode of SCD

Cardiac Arrest Survivor Evaluation 1. History & physical examination - Precipitating events - Associated conditions - Therapeutic and/or illicit drug usage - Family history 2. ECG & laboratory tests - Rhythm and/or conduction abnormalities - Ischemia, infarction hypertrophy - Electrolyte or metabolic abnormalities

Cardiac Arrest Survivor Evaluation 3. ECG monitoring 4. Echocardiography 5. Stress testing for provocation of ischemia or arrhythmia 6. Cardiac catherization 7. Electrophysiologic study

ECG Patterns Predicting SCD § Congenital long QT § Brugada syndrome : RBBB & ST elevation in V 1 -V 3 § RV dysplasia : negative T in right precordial leads & epsilon wave at the end of QRS § Large infarction pattern § DCMP pattern : low voltage in the limb leads with normal voltage or LBBB in precordial leads § HCMP : LBBB or high QRS voltage & prominent Q waves in lateral leads or giant negative T waves in precordial leads

Before & After PTCA with Stenting

Atrial Ventricle