SUDDEN UNEXPECTED DEATH IN THE YOUNG Jon Skinner, Jo Duflou & Julie McGaughran TRAGADY (Trans-Tasman Response Against Sudden Death in the Young )

BACKGROUND 400,000 sudden deaths per annum in USA Several thousand young adult sudden deaths No apparent warning signs in 50% of young SUD Distribution of causes of SUD poorly studied Significant number have a familial aetiology

METHODS All autopsies performed over a 10 yr period at DOFM Glebe were reviewed Cases of sudden, unexpected natural death between ages of 5 and 35 selected Sudden death defined as death occurring within 24 hours of onset of symptoms Review of “difficult” cases by cardiologist and pathologist

RESULTS ~200,000 deaths 25,277 investigated 3,854 aged natural

DEMOGRAPHICS Cardiac deaths: –241 cases –Mean age 26.8 ± 5.9 yrs –78.4% male –Mean BMI: 27.1 ± 8.4 kg/m 2 Non-cardiac deaths: –168 cases –Mean age 25.2 ± 7.6 yrs –58.9% male –Mean BMI: 26.5 ± 8.4 kg/m 2 Undetermined deaths: –18 cases

RESULTS - CARDIAC

PRIMARY ARRHYTHMIA 70 cases Criteria for inclusion: –Documented terminal arrhythmia –Documented collapse with cardiac arrest –Found dead after being asymptomatic in preceding 24 hours –No or minimal structural pathology Confirmed Long QT syndrome in 6 cases

ATHEROSCLEROSIS 59 cases, 96.6% male Mean BMI 30 Plaque rupture & thrombusAcute Myocardial infarct

MYOCARDITIS HYPERTROPHIC CARDIOMYOPATHY

ARRHYTHMOGENIC RIGHT VENTRICULAR DYSPLASIA (ARVD) Only 4 cases (1%) Compared to 13% in Italian study Importance of standard diagnostic criteria & appropriate tissue sampling

RESULTS – NON-CARDIAC

EPILEPSY 40 cases Majority classified as SUDEP: –Sudden death –Typically young adult, post- traumatic –Apparently during sleep –No evidence of status epilepticus –Often subtherapeutic levels of anti- epileptics

PULMONARY THROMBO-EMBOLISM 21 cases Higher body weight (mean 99 kg) & BMI (mean 34.7) than others Infrequent history of long-distance travel

NEGATIVE AUTOPSY DEATHS 18 cases Criteria for inclusion: –Unknown antemortem circumstances (15) –Advanced decomposition (3)

CONCLUSIONS The heart was structurally normal in about 30% of SCD cases Most likely cause of arrhythmia in structurally normal hearts are genetic syndromes, especially channelopathies Early onset atherosclerosis second most frequent COD Effective family screening is an important adjunct to the autopsy