What is the mortality rate of stent procedures?

Mortality Rates of Coronary Stent Procedures

The mortality rate of coronary stent procedures varies significantly based on patient risk factors and clinical presentation, with in-hospital mortality ranging from 0-3.7% for elective procedures to as high as 15.8% for emergency procedures, with drug-eluting stents showing similar mortality outcomes to bare-metal stents.

Mortality Rates by Procedure Type and Setting

Elective Procedures

• In-hospital mortality: 0-3.7% for elective stent procedures 1
• One-year mortality: 3.4% in low-risk patients (age <65 years, ejection fraction >30%) 1
• Cumulative survival rates for elective procedures:
  • 92% at 6 months
  • 88% at 1 year
  • 86% at 3 years 2

Emergency/Urgent Procedures

• In-hospital mortality: 13.7-45.4% for high-risk or emergency cases 1, 2
• One-year survival rate: approximately 54% for emergency procedures 2
• Mortality rate of 5.4% (reduced to 2.1% when excluding patients with cardiogenic shock) 3

Mortality by Stent Type

Bare-Metal Stents (BMS)

• In-hospital mortality: 0-4.3% 1
• 6-12 month mortality: 2.5-10.8% 1
• Long-term follow-up (15 months): 2.15% combined rate of definite, probable, or possible stent thrombosis 4

Drug-Eluting Stents (DES)

• Similar overall mortality to BMS at 15 months follow-up 4
• Stent thrombosis rate: 1.80% (combined definite, probable, or possible) 4
• Definite stent thrombosis: 0.65% (similar to BMS at 0.61%) 4
• Higher risk of very late stent thrombosis (between 12-15 months) compared to BMS 4

Factors Affecting Mortality Risk

Hospital and Operator Volume

• Hospitals performing <400 procedures/year: 1.5% mortality for stent procedures
• Hospitals performing >400 procedures/year: 1.1% mortality 1
• Significant inverse relationship between hospital volume and mortality rates 1

Patient-Specific Risk Factors

Factors significantly associated with increased mortality include:

• Advanced age
• Chronic renal insufficiency
• Presentation with myocardial infarction
• Chronic obstructive pulmonary disease
• History of cerebrovascular events
• Reduced left ventricular ejection fraction 5

Anatomical Considerations

• Left main coronary artery (LMCA) disease:
  • Unprotected LMCA with normal left ventricular function: 3.4% one-year mortality 1
  • Protected LMCA (with bypass grafts): lower mortality risk 1, 2
  • Bifurcation vs. non-bifurcation lesions: higher risk with bifurcation lesions (TVR rates 13% vs. 3%) 1

Clinical Implications

1. Procedure Timing: For non-emergency cases, elective procedures carry significantly lower mortality risk than emergency procedures 2

2. Hospital Selection: Patients should be referred to high-volume centers (>400 procedures/year) when possible, as these centers demonstrate lower mortality rates 1

3. Risk Assessment: Careful evaluation of patient-specific factors is crucial, as mortality is strongly influenced by baseline clinical characteristics such as left ventricular function and comorbidities 1

4. Stent Selection: While DES and BMS show similar overall mortality rates, DES demonstrate lower rates of target vessel revascularization (43% reduction) 4

Pitfalls and Caveats

• Mortality statistics from older studies may not reflect current outcomes due to advances in stenting techniques and adjunctive pharmacotherapy 1
• In-hospital mortality figures may not capture late complications such as very late stent thrombosis, which occurs more frequently with DES 4
• Procedure-related mortality should be distinguished from mortality due to progression of underlying disease 5
• The relationship between volume and outcomes is statistical; some low-volume centers may achieve excellent results 1

When comparing coronary stenting to medical therapy alone, coronary bypass surgery (CABG) has shown a mortality benefit (OR=0.84; 95% CI: 0.71-0.97), while stenting has not demonstrated a significant mortality reduction compared to optimal medical therapy in stable coronary artery disease 6.