A 54-year-old man with a history of type 2 diabetes and coronary artery disease is admitted to the coronary care unit with worsening angina and hypertension. His pain is controlled with intravenous nitroglycerin, and he is treated with aspirin, beta-blockers to lower his heart rate, and angiotensin-converting enzyme (ACE) inhibitors to lower his blood pressure. Cardiac enzymes are normal. He undergoes coronary angiography, which reveals no significant stenosis. By the next day, his urine output had diminished to 200 mL over 24 hours.
Examination at that time reveals that he is afebrile, his heart rate is regular at 56 bpm, and his blood pressure is 109/65 mm Hg. His fundus reveals dot hemorrhages and hard exudates, his neck veins are flat, his chest is clear, and his heart rhythm is normal, with an S4 gallop and no murmur or friction rub. His abdomen is soft without masses or bruits. …
