Percutaneous coronary intervention (PCI) is frequently complicated by type 4a myocardial infarction (MI), which is associated with an increased risk of mortality. We assessed the usefulness of the angiography-derived hemodynamic index (ADDED), which is based on the extent of myocardium at risk and on the anatomical lesion severity, in predicting type 4a MI in patients with chronic coronary syndrome (CCS) undergoing PCI. We enrolled 442 patients treated with single-vessel PCI. The ADDED index was calculated as the ratio of the Duke Jeopardy Score to the minimum lumen diameter assessed with quantitative angiography analysis. Type 4a MI was defined according to the 4th Universal Definition of MI. The overall population was divided into tertiles of ADDED index. Type 4a MI occurred in 5 patients (3.3%) in the ADDED-low tertile, 8 (5.5%) in the ADDED-mid tertile, and 26 (17.7%) in the ADDED-high tertile (p < 0.0001). At ROC curve analysis, the ADDED index could significantly discriminate between patients with and without type 4a MI (area under the curve 0.745). At multivariate analysis, an ADDED index value > 5.25 was the strongest independent predictor type 4a MI. Our results support the role of the ADDED index as a predictor of type 4a MI in patients with CCS treated with elective PCI of a single vessel. Whether a selective use of additional preventive measures in patients considered at high risk based on ADDED index values may improve peri-procedural and long-term outcomes remains to be tested in dedicated investigations.