- Relevant clinical history and physical exam:
A 68-year old man was admitted to abnormal coronary CT findings and treadmill test. He didn't present effort-related chest discomfort or pain. He checked routine health care problem due to private curiosity. He had no specific coronary artery risk factors except age and old age.

- Relevant test results prior to catheterization:
A CT scan checked other hospital showed significant stenosis at proximal to mid LAD with mixed plaque characterization.

- Relevant catheterization findings:
Baseline coronary angiogram showed tight stenosis of proximal LAD with significant stenosis at the shaft of diagonal branch. (Figure 1, Figure 2)

- Procedural step:
An 8 Fr JL4 3.5 guiding catheter was engaged in the left coronary artery through the 8Fr femoral sheath. IVUS examination showed encircling heavy plaque burden in proximal LAD but relatively preserved diagonal ostium. (Figure 3, Figure 4) But IVUS catheter could not be advanced into more distal portion of diagonal branch due to tight stenosis. Firstly, we performed balloon angioplasty in the shaft lesion of diagonal branch with Sprinter 2.5 X 20mm & Dura-star 2.5 X 15mm. (Figure 5) Predilation was not successful, so we used cutting balloon 2.5 X 10 mm. (Figure 6) After then, We deployed bifurcation stent (Crushing technique) using XIENCE-V 2.5 X 23 mm at Diagonal branch & XIENCE-V 3.5 X 23 mm at LAD. (Figure 7) After re-wiring of 0.014 inch guide wire, step-wise balloon dilation(Maverick 1.5 X 20 mm --> Sprinter 2.0 X 20 mm --> Dura-Star 2.5 X 20 mm) was performed at diagonal branch. Finally, we performed kissing balloon dilatation using Dura-Star 2.5 X 20 mm at diagonal branch & Quantum-Maverick 3.5 X 15 mm at LAD. (Figure 8) Final angiogram showed well-expanded and well-positioned stents. (Figure 9, Figure 10).