Researchers found that CAD risk more than doubled when the low attenuation area (LAA%) exceeded 16.95%. The study retrospectively analyzed 392 COPD patients without prior CAD, who underwent HRCT between 2015 and 2020. Emphysema extent was measured as the percentage of low attenuation areas below −950 Hounsfield units, with severe emphysema defined as LAA% above 16.95%. Patients with severe emphysema had higher SYNTAX scores, indicating more complex coronary lesions (median 16.29 vs. 10.0 in mild emphysema). Rates of percutaneous coronary intervention (PCI) were significantly higher in patients with severe emphysema (68.2% vs. 33.3%).