Moderate-to-severe coronary calcification outcomes after PCI: A systematic review and meta-analysis of clinical presentation, imaging guidance, and contemporary stent era

Background: Moderate to severe coronary calcification is generally considered to predict lesion complexity following percutaneous coronary intervention. It remains unknown whether the adverse prognostic impact persists in the current PCI era, especially with the development of stent technology, intracoronary imaging and lesion preparation techniques. Methods: A systematic review and meta-analysis were performed to assess the impact of moderate-to-severe coronary calcification on outcomes after PCI. Studies contrasting moderate-to-severe calcification with mild or no calcification were selected. The principal outcomes included cardiac mortality, MACE, recurrent myocardial infarction, and target lesion revascularization. Pooled relative risks with 95% confidence intervals were calculated using a random-effects Mantel–Haenszel model, with heterogeneity evaluated by the I² statistic. Subgroup analyses were chosen based on clinical presentation, imaging guidance, and stent production. Result: Six studies including over 19,000 patients were included. Moderate-to-severe coronary calcification was linked to a markedly elevated risk of cardiac mortality (RR 2.22, 95% CI 1.87–2.63; I² = 0%), major adverse cardiovascular events (MACE) (RR 1.74, 95% CI 1.40–2.16; I² = 83%), recurrent myocardial infarction (RR 1.57, 95% CI 1.30–1.89; I² = 31%), and target lesion revascularization (RR 1.79, 95% CI 1.34–2.38; I² = 80%) following PCI. Subgroup analysis showed a stronger association between TLR and non-ACS patients and clinical studies using current-generation stents, although calcification was detrimental regardless of intracoronary imaging guidance.. Conclusion: Despite advancements in modern stents and developing PCI techniques, moderate-to-severe coronary calcification persists in providing a significant residual risk following revascularization.