From the Guidelines
Stenting in Non-ST-Elevation Myocardial Infarction (NSTEMI) should be performed immediately in patients with very high-risk criteria, such as haemodynamic instability or recurrent chest pain, and early (within 24 hours) in patients with high-risk criteria, such as elevated troponin levels or ST-segment depression >1 mm in ≥6 leads.
Timing of Invasive Strategy
- Immediate invasive strategy (<2 hours) is recommended in patients with very high-risk criteria, including:
- Haemodynamic instability or cardiogenic shock
- Recurrent or refractory chest pain despite medical treatment
- Life-threatening arrhythmias
- Mechanical complications of MI
- Heart failure clearly related to NSTEMI
- Presence of ST-segment depression >1 mm in ≥6 leads additional to ST-segment elevation in aVR and/or V1 1
- Early invasive strategy (within 24 hours) is recommended in patients with high-risk criteria, including:
- Diagnosis of NSTEMI suggested by the diagnostic algorithm
- Dynamic or presumably new contiguous ST/T-segment changes suggesting ongoing ischemia
- Transient ST-segment elevation
- GRACE risk score >140 1 ### Evidence Supporting Early Invasive Strategy
- The FRISC-II trial showed that an early invasive strategy reduced death or MI at 6 months and 1 year compared to a noninvasive strategy 2
- The TACTICS-TIMI 18 trial demonstrated that an early invasive strategy reduced death, MI, or rehospitalization for ACS at 6 months compared to a more conservative strategy 3
- A meta-analysis of contemporary randomized trials in NSTEMI supported a long-term mortality and morbidity benefit of an early invasive strategy compared to an initial conservative strategy 3 ### Considerations for Delayed Invasive Strategy
- A delayed invasive strategy may be considered in patients without high-risk criteria or in those who are stable and have a low risk of clinical events 1, 4
- The TIMACS trial showed that an early invasive strategy did not have an incremental benefit in reducing MI or death compared to a delayed invasive strategy, but reduced recurrent/refractory ischemia and length of stay 5
From the Research
Timing of Stenting in NSTEMI
The optimal timing of stenting in Non-ST-Elevation Myocardial Infarction (NSTEMI) patients is a topic of ongoing research and debate. Several studies have investigated the outcomes of early versus delayed invasive strategies in NSTEMI patients.
- Early Invasive Strategy: An early invasive strategy is preferred to a delayed invasive strategy in reducing all-cause death in patients with pre-PCI TIMI 0/1 6. Additionally, an early invasive strategy is associated with reduced rates of refractory angina and rehospitalization in the shorter term and myocardial infarction in the longer term 7, 8.
- Delayed Invasive Strategy: However, in patients with pre-PCI TIMI 2/3, both early and delayed invasive strategies are acceptable 6. Moreover, a delayed invasive strategy may be suitable for patients with complex lesions or those who are at lower risk for recurrent events 9.
- Patient-Specific Factors: The decision to stent in NSTEMI patients should be individualized based on patient-specific factors, such as age, comorbidities, and lesion complexity. For example, older adults with NSTEMI may not benefit from an early invasive strategy compared to younger adults 9.
- Clinical Outcomes: The clinical outcomes of interest in NSTEMI patients include major adverse cardiac events (MACEs), such as all-cause death, recurrent myocardial infarction, and any repeat revascularization. The choice of stenting strategy should be guided by the potential to reduce these outcomes 6, 7, 9, 8.
Key Considerations
When deciding when to stent in NSTEMI patients, the following key considerations should be taken into account: