Molecular Autopsy Study

Inclusion Criteria: * Index case age between birth - 45 years * Clinical presentation of sudden / unexplained death (believed to be cardiac in nature OR secondary to a massive unprovoked pulmonary embolism with no prior diagnosis of prothrombotic disease) Exclusion Criteria: * Premature death secondary to murder, suicide or external causal event * Premature death thought secondary to known chronic comorbid medical condition * Premature death thought secondary to end-organ failure (kidney, liver, lung) other than heart * Previously diagnosed with hypertrophic cardiomyopathy (HCM) * Prior myocardial infarction (regardless of stenting or bypass) * Prior cerebrovascular accident (stroke or TIA) * History of open heart surgery (for any reason) * History of severe, untreated hypertensive heart disease * History of illicit drug use * History of heavy alcohol abuse * History of severe pulmonary disease * History of morbid obesity