Gadolinium-based coronary angiography in patients with contraindication for iodinated x-ray contrast medium: a word...

In coronary angiography, the use of contrast agents containing iodine still defines the gold standard. In patients with contraindications for iodine exposition, gadolinium has been considered to be a safe alternative to standard iodinated contrast medium for coronary angiography. The aim of the present study was to assess the safety and technical quality of gadolinium-based coronary angiography.

Nineteen consecutive patients with contraindication to iodinated contrast medium underwent gadolinium-based coronary angiography. Contraindications included previous anaphylactic shock or severe allergic reaction to iodinated contrast medium (n = 13) or thyrotoxicosis (n = 6). Gadolinium was diluted 1:1 with sodium chloride before application. Patients were clinically observed for potential side effects, and renal function was assessed by determination of creatinine values and calculation of creatinine clearance in pre- and postprocedural blood samples. Image quality was evaluated by two independent observers, and classified into three different categories (grade 1, high diagnostic quality; grade 2, moderate diagnostic quality; and grade 3, poor quality).

During angiography, a mean of 32.6 +/- 10.9 mL (range 10-45 mL) gadolinium was used. No patient developed a significant impairment of renal function within 24 hours after the examination (mean creatinine value preprocedural: 1.12 +/- 0.15 mg/dL, postprocedural: 6 hours 1.15 +/- 0.18 mg/dL, 24 hours 1.13 +/- 0.16 mg/dL) (baseline vs. 6 hours P = 0.23, baseline vs. 24 hours P = 0.66, 6 hours vs. 24 hours P = 0.12) (mean creatinine clearance preprocedural: 73.8 +/- 18 mg/dL, postprocedural: 6 hours 71.7 +/- 16.8 mg/dL, 24 hours 73.2 +/- 17.8 mg/dL) (baseline vs. 6 hours P = 0.2, baseline vs. 24 hours P = 0.71, 6 hours vs. 24 hours P = 0.21). Four patients (21%) suffered severe complications due to gadolinium application, such as malignant cardiac arrhythmias (n = 3) and hemodynamic decompensation (n = 1). Image quality was generally reduced in comparison to iodine contrast coronary angiography, but was adequate for diagnostic purposes (13 patients [68.4%] had reasonably good picture contrast [grade 2.1 +/- 0.3]; in 6 patients [31.6%], image quality was satisfactory [grade 2.6 +/- 0.13]). Opacification of distal vessels as compared to proximal segments was remarkably reduced.

Gadolinium-based coronary angiography is a potential alternative technique in patients with allergy to iodinated contrast medium or thyrotoxicosis with reduced, but acceptable, image quality for diagnostic purposes. Nevertheless, possible life-threatening side effects and complications have to be considered.