Beading-expanded conus branch after overfilling with contrast medium.

Transradial coronary angiography of a 74-year-old man who was admitted with atypical chest pain revealed no obstructive disease in the left anterior descending (LAD) or left circumflex arteries (LCX; Figure 1A). During right coronary angiography with a 5-French tiger-shaped universal catheter (Terumo Corporation, Japan), the conus branch was superselected, and beading expansion of this branch was observed after overfilling with contrast medium (white arrow in Figure 1B). The catheter was removed immediately, and visualization of the beading-expanded conus branch persisted for about 40 seconds. The the stain completely disappeared thereafter (Figure 1C). Under the circumstances, there was no significant change in symptoms, vital signs or electrocardiogram. Angiography was then continued, and it revealed a nearly normal right coronary artery and conus branch (Figure 1D). No pericardial effusion was apparent in serial ultrasound cardiogram-echocardiogram examination. We posit that beading expansion of the conus branch is secondary to artery overfilling with contrast medium; the special curve of the universal catheter facilitated the superselection of the conus branch when performing right coronary angiography. Overfilling with contrast medium could have resulted in conus branch expansion, rupture, malignant arrhythmia, among other untoward events.1,2 This is a profound example of this phenomenon, and, to our knowledge, the first one reported. Attempts should be made to avoid superselection of the conus branch and overfilling with contrast medium to minimize the occurrence of possible complications.

Figure 1

A) Left coronary angiography; B) Visualization of expanded conus branch for overfilled with contrast medium; C) The stain disappeared 40 seconds later; D) Right coronary angiography revealed a nearly normal right coronary artery and conus branch.