Numerous laboratory tests and imaging, such as aldosterone and ARO levels, both before and after tilting, creatinine, urea, GFR, sodium, potassium, pro BNP, TSH, FT3, FT4, and a 24-hour collection for electrolytes were collected. Abdominal ultrasound examinations, computed tomography of the abdomen, and Doppler ultrasound of the renal arteries were performed to exclude secondary causes of hypertension. Clinical BP measurements were performed three times, as well as, ambulatory blood pressure monitoring (ABPM) and echocardiography was conducted. Whole blood samples were taken and baseline platelet aggregation was determined using the VerifyNow analyzer from Accumetrics. In Group 1, two whole blood samples for VerifyNow Aspirin test were assayed. In Group 2, four whole blood samples for VerifyNow Aspirin and P2Y12 tests were assayed.