Aminophylline does not protect against radiocontrast nephropathy in patients undergoing percutaneous angiographic procedures.

BACKGROUND: Radiocontrast nephropathy (RCN) is one of the leading causes of hospital-acquired acute renal insufficiency. Adenosine, a renal vasoconstrictor, is thought to play a role in RCN. In this study, aminophylline, a non-selective adenosine-competitive inhibitor, was evaluated as a potential agent to protect against RCN. METHODS: Twenty-six patients treated with 200 mg intravenous aminophylline immediately prior to percutaneous coronary and peripheral procedures were individually matched to 26 controls for baseline creatinine (Cr), diabetes mellitus and amount of contrast used. The aminophylline-treated group was also similar to control with respect to baseline ejection fraction, amount of post-procedure hydration, age, blood pressure and the use of nephrotic drugs. RESULTS: There was no significant difference between the change from baseline Cr to peak measured Cr in either cases or controls. Also, when a change in Cr > or =25% from baseline was considered significant, Fisher's exact test did not show a difference between the 2 groups. CONCLUSION: Aminophylline does not appear to add a protective role in preventing against RCN in patients undergoing percutaneous angiographic procedures.

Comparison of right ventricular outflow tract and apical lead permanent pacing on cardiac output.

Cardiac output was measured in 89 patients using transthoracic continuous-wave echo Doppler comparing right ventricular outflow tract pacing with the right ventricular apex at the time of permanent pacemaker implantation. Overall, cardiac output improved 18.8% (p <0.0001) and cardiac index 21.0% (p <0.0001) with outflow tract placement; patients with a lower baseline cardiac index had a greater percent improvement with outflow tract placement.

Thallium-201 scintigraphy after intravenous infusion of adenosine compared with exercise thallium testing in the diagnosis of coronary artery disease.

Adenosine is an endogenously produced compound that has significant effects as a coronary and systemic vasodilator. Previous studies suggest that intravenous infusion of adenosine, coupled with thallium-201 scintigraphy, may have specific value as a noninvasive means of evaluating coronary artery disease. The purpose of this study was to compare the diagnostic value of adenosine thallium testing with that of standard exercise thallium testing. One hundred subjects were studied with exercise thallium imaging and thallium imaging after adenosine infusion, including 47 with angiographically proved coronary artery disease and 53 control subjects. The overall sensitivity of the thallium procedures was 81% for the exercise study and 83% for the adenosine study (p = NS); the specificity was 74% for the exercise study and 75% for the adenosine study (p = NS). The diagnostic accuracy of the exercise study was 77% and that of the adenosine study was 79%. Ninety-four percent of subjects had an adverse effect due to the adenosine infusion; however, most of these effects were mild and well tolerated. All adverse effects abated within 30 to 45 s of the termination of the study, consistent with the very brief half-life of the agent. Thus, thallium-201 scintigraphy after intravenous infusion of adenosine has a diagnostic value similar to that of exercise thallium testing for evaluation of coronary artery disease. Adenosine thallium testing may be particularly useful in evaluating patients unable to perform treadmill exercise testing.