Effects of hormone replacement on progression of coronary calcium as measured by electron beam tomography.

Purpose: The recent Women's Health Initiative (WHI) results have demonstrated that combined estrogen plus progestin imparts a small but significant increase in cardiovascular risk and breast cancer among asymptomatic women. However, the effect and potential benefit of unopposed estrogen is not as clear. We sought to evaluate the progression of subclinical atherosclerosis in postmenopausal women using no hormone replacement therapy (HRT), combined therapy, and estrogen alone in an observational study.

Patent foramen ovale and the platypnea-orthodeoxia syndrome.

The platypnea-orthodeoxia syndrome is a rare but important condition caused by a variety of clinical entities. Several mechanisms have been postulated to cause platypnea and orthodeoxia. These mechanisms mainly involve intracardiac shunting, pulmonary vascular shunting, and ventilation-perfusion mismatching.