Coronary artery dissection assessment can be challenging. Angiography is limited to safely guide angioplasty when really needed. The technical difficulty is due to the co-existence of two lumens separated by an intimal flap and the need to advance the guidewire into the true channel to ensure optimal results without extending the dissection.
A 43-year-old man was admitted for ST-segment elevation myocardial infarction. The first injection showed complete occlusion of the vertical segment of the right coronary artery ( Fig. 1 A ). The probe approach setup was complicated by an ostial dissection ( Fig. 1 B). We barely succeeded in establishing a first guidewire (GW1), advancement of which was difficult. A second guidewire (GW2) was then introduced. The guidewires had different routes, to such an extent that it was not possible to determine by angiography which guide was in the right channel ( Fig. 1 C). Optical coherence tomography (OCT) was performed on GW2. Fig. 2 A (top picture) is a long view of the artery (proximal part on the right side; distal part on the left) and corresponds to the angiography in Fig. 1 C. Fig. 2 B–D show the different interesting points with complementary axial views. Proximal OCT ( Fig. 2 D, D′) gave excellent definition of the arterial lumen, which was occupied by the fibre and the two guidewires. The false lumen of dissection – a non-compressive crescent-shaped mark – is symbolized by the asterisk. The intermediate fractions ( Fig. 2 C, C′) show intimal rupture and GW1 leaving the arterial lumen to reach the dissecting haematoma. Longitudinal analysis confirmed the position of the two guidewires and ensured the reliable presence of GW2 in the real channel. Distal OCT cuts ( Fig. 2 B, B′) gave little information about depth because the compressive haematoma prevented infrared diffusion. GW1 was no longer observable while GW2 was still in the true lumen. Angioplasty was successfully performed on GW2 ( Fig. 1 D).
