Heart and Vascular Health Study
The Heart and Vascular Health (HVH) VTE Study is a case-control study of risk factors for cardiovascular outcomes set at Group Health (GH), an integrated health care delivery system in western Washington State. Cases include venous thromboembolism (VTE), myocardial infarction (MI), stroke, and atrial fibrillation (AF), with a shared common control group frequency matched to MI cases on age (within decade) sex, treated hypertension, and calendar year of identification. Study approval was granted by the human subjects committee at GH, and written informed consent was provided by all study participants. Eligibility and risk factor information were collected by trained medical record abstractors from a review of the GH medical record using only data available prior to the event date of cases and a randomly selected date for the controls. All VTE, MI, stroke and AF events were verified by medical record review.
For the TOPMed data set, only incident idiopathic cases of VT and early-onset (age <=60 years) cases of AF without underlying heart failure, myocardial infarction, or valvular heart disease were included. Within the HVH study, VT and AF cases were diagnosed in both inpatient and outpatient settings. A venous blood sample was collected from all consenting subjects, and DNA was extracted from white blood cells using standard procedures.