Sodium bicarbonate vs sodium chloride for the prevention of contrast medium-induced nephropathy in patients undergoing coronary angiography: a randomized trial.

Context: Sodium bicarbonate has been suggested as a possible strategy for prevention of contrast medium-induced nephropathy, a common cause of renal failure associated with prolonged hospitalization, increased health care costs, and substantial morbidity and mortality.

Objective: To determine if sodium bicarbonate is superior to sodium chloride for preventing contrast medium-induced nephropathy in patients with moderate to severe chronic kidney dysfunction who are undergoing coronary angiography.

Design, Setting, And Patients: Randomized, controlled, single-blind study conducted between January 2, 2006, and January 31, 2007, and enrolling 353 patients with stable renal disease who were undergoing coronary angiography at a single US center.

Overestimation of aortic valve gradient measured by Doppler echocardiography in patients with aortic stenosis.

We describe a series of patients with suspected aortic stenosis who were noted to have a significant aortic valve gradient by Doppler echocardiography but only a minimal gradient during cardiac catheterization. Although the pressure recovery phenomenon partially explained this discrepancy, a difference still persisted, particularly in peak gradients. The overestimation occurred at much lower cardiac catheterization gradients than previously reported.