JDEPTH-LM Registry is a prospective, observational, multi-center study designed for the efficacy and safety of Double-effect kissing balloon technique (W-KBT) in left main (LM) bifurcation percutaneous coronary intervention (PCI) using Perfusion balloon (PB) and Drug coated balloon (DCB) in patients with left main coronary artery disease (LMD) with left circumflex artery (LCx) ostium stenosis.

JDEPTH-LM Registry is a prospective observational multi-center study. The investigators will enroll and treat patients in the registry who meet the selection criteria under usual care and for whom PCI with W-KBT following on crossover stenting for LMT-LAD direction, proximal optimization technique (POT), and conventional kissing balloon technique (C-KBT) is the optimal treatment. The operators shall obtain oral or written consent from patients who meet the criteria before performing PCI, indicating the intention to perform PCI with W-KBT, and shall keep records. The investigators will continuously register cases attempting PCI with W-KBT according to the protocol and evaluate its efficacy and safety using data from this multi-center registry.

Inclusion Criteria:

1. Age ≥ 18 years
2. Patient with stable coronary artery disease, non-ST-elevation myocardial infarction, or unstable angina
3. Left main disease confirmed by coronary angiography or coronary CT angiography
4. Clinical and anatomical eligibility for PCI as agreed by the local Heart Team
5. Patient with consent prior to undergoing PCI
6. Left main Medina classification (1,1,1), (1,0,1), (0,1,1), (0,0,1) confirmed by coronary angiography
7. De novo target lesion in LMT-LAD amenable for crossover stenting with provisional side-branch approach as determined by PCI operator
8. De novo ostial LCx lesions
9. Lesion indicated in No. 8 with a length of less than 10 mm or a stenosis of less than 70% confirmed by coronary angiography

Exclusion Criteria:

1. Inability to provide written informed consent
2. Patient with a history of ST-elevation myocardial infarction within the previous 1 week
3. Patient in a state of cardiogenic shock
4. Patient with a history of coronary artery bypass grafting
5. Patient with malignant tumors or other conditions with a life expectancy of less than one year
6. Patient considered suitable for stent placement in the ostial LCx from a medical perspective
7. Patient considered unsuitable for anti-thrombotic therapy after PCI
8. Other patient whom the investigator deems unsuitable for the safe conduct of LM-PCI, including W-KBT

Subjects ≥ 18 years of age with de novo LMD with LCx ostium stenosis presenting with stable angina, non-ST-elevation myocardial infarction, or unstable angina that are suitable for percutaneous coronary intervention including W-KBT processes. Approximately 280 subjects at 17 sites in Japan will be enrolled. Subjects will be followed through discharge and 12 months in routine clinical practice.