What are the risks and complications of percutaneous coronary intervention (PCI) in older adults or patients with chronic kidney disease, diabetes, multivessel disease, or complex coronary lesions?

Risks and Complications of Percutaneous Coronary Intervention

PCI carries a procedural mortality of <1.2%, Q-wave myocardial infarction in 2–2.5% of cases, coronary perforation in approximately 0.2%, plus risks of bleeding, contrast-induced acute kidney injury, and vascular access complications—with risk magnitude varying substantially by patient characteristics and lesion complexity. 1

Major Procedural Complications

Mortality and Myocardial Infarction

• Overall in-hospital mortality for standard PCI is approximately 0.5%. 1
• Q-wave myocardial infarction occurs in <2.5% of cases, though non-Q-wave infarctions are more frequent, particularly during saphenous vein graft interventions. 2, 1
• Death following PCI is most frequently associated with coronary artery occlusion and pronounced left ventricular failure. 2

Coronary Perforation

• Coronary perforation occurs in approximately 0.2% of procedures and is more common with ablative technologies (rotational atherectomy, directional atherectomy, excimer laser angioplasty). 2, 1
• Perforation risk is elevated in elderly patients and women. 2, 1
• Approximately 20% of perforations are guidewire-related; most result from device oversizing or ablative technology use. 2, 1
• Ellis Type III perforations (frank extravasation ≥1 mm) require immediate covered stent deployment. 1
• Distal vessel perforations are best managed initially with coil embolization. 1

Bleeding Complications

• Periprocedural bleeding is an independent predictor of subsequent mortality. 1
• Key bleeding risk factors include advanced age, low body-mass index, chronic kidney disease, baseline anemia, intensity of antiplatelet/thrombin inhibition, access-site choice, and sheath size. 1
• Radial arterial access reduces bleeding risk compared with femoral access. 1
• Access-site complications include pseudoaneurysm (approximately 0.01%), compartment syndrome, and local hematoma formation. 1

High-Risk Patient Populations

Elderly Patients (Age ≥75 Years)

• Age ≥75 years is one of the major clinical variables associated with increased risk of complications. 2
• The very elderly have the highest risk of adverse outcomes, with morphologic and clinical variables compounded by advanced years. 2
• Despite higher risk, procedural success rates and short-term outcomes in the stent era are comparable to younger patients. 2
• Higher incidence of comorbidities must be taken into account when considering PCI in elderly patients. 2

Women

• In-hospital mortality is significantly higher in women, and an independent effect of gender on acute mortality persists after adjustments for baseline higher-risk profile. 2
• Women undergoing PCI are older and have higher incidence of hypertension, diabetes, hypercholesterolemia, and comorbid disease compared to men. 2
• Angiographic outcomes and incidence of myocardial infarction and emergency bypass surgery are now similar between women and men. 2

Diabetes Mellitus

• Patients with diabetes have significantly higher mortality rates: 6-week mortality 11.6% vs. 4.7%, 1-year mortality 18.0% vs. 6.7%, and 3-year mortality 21.6% vs. 9.6% compared to non-diabetic patients. 2
• Stenting with GP IIb/IIIa inhibitors significantly reduces 6-month death and myocardial infarction rates in diabetic patients. 2
• Drug-eluting stents significantly reduce restenosis in diabetic patients compared with bare-metal stents. 2
• For diabetic patients with three-vessel disease and intermediate or high SYNTAX score (>22), PCI is not recommended (Class III). 2

Chronic Kidney Disease

• Chronic kidney disease is an independent risk factor for worse prognosis after PCI, with higher risk of complications including bleeding, acute kidney injury, and death. 2, 3
• Patients with CKD have a nearly 2-fold risk for death, myocardial infarction, or stroke compared to those with normal renal function. 3
• The incidence of contrast-induced acute kidney injury rises with baseline eGFR <60 mL/min/1.73 m², congestive heart failure, diabetes, and higher contrast volume. 1
• Prophylactic intravenous hydration is mandatory for all patients undergoing PCI; contrast volume must be minimized in CKD patients. 1
• N-acetyl-L-cysteine provides no benefit for acute kidney injury prevention (Class III: No Benefit). 1
• In multivessel PCI for CKD patients, staged procedures reduce acute kidney injury risk (11.2%) compared to single-session multivessel PCI (21.4%). 4

Multivessel Disease

• Patients with multivessel disease have increased periprocedural risk of ischemic complications and increased mortality. 2
• For multivessel disease with LVEF ≤35%, CABG is recommended over medical therapy alone to improve long-term survival. 5
• PCI may be considered as an alternative to CABG for high surgical risk patients with LVEF ≤35%, though evidence is weaker. 5

Complex Coronary Lesions

Heavily Calcified Lesions

• Severely calcified lesions respond poorly to balloon angioplasty; incomplete and asymmetrical stent expansion occurs in the majority of cases. 2
• Aggressive high-pressure balloon dilatation to remedy underexpanded stents may result in coronary artery rupture. 2
• Rotational atherectomy is reasonable for fibrotic or heavily calcified lesions that cannot be crossed by a balloon catheter or adequately dilated before stent implantation (Class IIa). 2

Saphenous Vein Graft Interventions

• PCI of saphenous vein grafts has success rates exceeding 90%, death <1.2%, Q-wave myocardial infarction <2.5%. 2
• Non-Q-wave myocardial infarction incidence may be higher than with native coronary arteries. 2
• GP IIb/IIIa blockers have not been shown to improve results of angioplasty in vein grafts. 2
• Native vessels should be treated with PCI if feasible; patients with older and/or severely diseased saphenous vein grafts may benefit from elective repeat CABG rather than PCI. 2

Left Main Disease

• For left main disease with high SYNTAX score (≥33), PCI is not recommended (Class III). 2
• For left main disease with low SYNTAX score (≤22), PCI is recommended as an alternative to CABG, given lower invasiveness and non-inferior survival. 2, 5

Hemodynamic Support Considerations

• Patients in cardiogenic shock, with severely depressed left ventricular function, or borderline hemodynamics benefit from intra-aortic balloon pump insertion before coronary instrumentation. 2, 1
• Full cardiopulmonary support should be reserved for cases of extreme hemodynamic compromise. 2, 1
• Obtaining contralateral femoral access before initiating high-risk PCI facilitates rapid balloon-pump insertion if needed. 2, 1

Additional Procedural Risks

No-Reflow Phenomenon

• No-reflow (suboptimal myocardial perfusion despite restored epicardial flow) is linked to reduced survival and results from inflammation, endothelial injury, edema, athero-embolization, vasospasm, and reperfusion injury. 1
• Manual thrombus aspiration may improve tissue perfusion and ST-segment resolution. 1

Anticoagulation-Related Bleeding

• Triple therapy (oral anticoagulation plus dual antiplatelet therapy) markedly increases bleeding risk. 1
• Continuing antiplatelet therapy beyond 1 year in patients on oral anticoagulation adds bleeding without additional ischemic protection. 1

Post-Procedural Warning Signs

• Recurrent chest pain with electrocardiographic changes accompanied by leukocytosis warrants investigation for procedural complications. 1
• Fever or hemodynamic instability with leukocytosis should prompt evaluation for infection or other adverse events. 1
• Persistent leukocytosis beyond 4–5 days without downward trend requires further diagnostic work-up. 1