Background: Coronary angiography using 4 F catheters may reduce access-site complications and enable early ambulation, although earlier studies suggested that the quality of images may be an issue of concern.
Methods and results: To ascertain the quality of angiographic images and safety of early ambulation, 500 patients were randomized to coronary angiography with either 4 F or 6 F catheters. Procedural characteristics, angiographic quality scores and results of ambulation were analyzed in the two groups. Patients in the 4 F group were mobilized at 2 hours post-procedure while those in the 6 F group were ambulated at 6 hours. There was no procedure-related complication in either group. The procedure was successfully completed in 250 of 252 patients randomized to the 4 F group. In two patients in the 4 F group, sheaths were upgraded to 6 F to complete the procedure, as difficulty was encountered in hooking the coronary ostium with a 4 F Judkin's catheter. Coronary angiographic quality scores in these two groups were comparable. Angiographic scores for the 4 F and 6 F groups for the left coronary artery averaged 4.45+/-0.5 and 4.58+/-0.3 (p>0.1), respectively. The right coronary artery scores averaged 4.30+/-0.4 and 4.35+/-0.2 (p>0.1) in the 4 F and 6 F groups. Angiographic scores for the left ventricular angiogram averaged 4.22+/-0.1 and 4.44+/-0.3 (p>0.1) in the 4 F and 6 F groups, respectively. None of the angiograms were assigned a score of <3.0 (not diagnostic). The total contrast volume consumed in the two groups was also equivalent. There were no groin-related complications in the 4 F group although these patients were ambulated 2 hours after the procedure.
Conclusions: Coronary angiography performed with a 4 F catheter is a safe and reliable procedure. The quality of image obtained with a 4 F catheter is equivalent to that obtained with a 6 F catheter. Early ambulation at 2 hours is feasible without compromising safety.