Keywords: 3-dimensional imaging; American Academy of Neurology; American Society of Anesthesiologists; Eisenmenger syndrome; arrhythmias; atrial-septal aneurysm; color Doppler; functional residual capacity; hypercarbia; hypoxia; morbid obesity; nitric oxide; obstructive sleep apnea; patent foramen ovale; platypnea; pressure gradient; prostaglandin; provocative maneuver; pulmonary hypertension; pulmonary vascular resistance; right-to-left shunt; saline contrast; systemic vascular resistance; transesophageal echocardiography; transthoracic echocardiography; tricuspid annular plane systolic excursion.