From the Guidelines
The 2017 AHA/ACC clinical performance and quality measures for adults with ST-elevation and non-ST-elevation myocardial infarction study recommends a cut-off point of 120 minutes for PCI. This study, published in the journal Circulation 1, emphasizes the importance of timely reperfusion therapy in patients with ST-elevation myocardial infarction (STEMI). The recommended cut-off point of 120 minutes is based on the idea that the benefits of primary PCI over fibrinolysis diminish when the PCI-related delay exceeds this time frame.
Key Points
- The 120-minute threshold represents the maximum acceptable delay from first medical contact to balloon inflation during which PCI remains superior to fibrinolysis in terms of patient outcomes.
- This time-sensitive approach is crucial because myocardial salvage decreases progressively with longer ischemic times, emphasizing the "time is muscle" concept in acute coronary syndrome management.
- The study recommends that in the absence of contraindications, fibrinolytic therapy should be administered to patients with STEMI at non-PCI-capable hospitals when the anticipated FMC-to-device time at a PCI-capable hospital exceeds 120 minutes because of unavoidable delays.
Clinical Implications
- The 120-minute cut-off point guides decisions about whether to transfer patients to PCI-capable centers or administer immediate fibrinolytic therapy.
- The study highlights the importance of providing reperfusion therapy as rapidly as possible, with the goal of minimizing ischemic time and maximizing myocardial salvage.
- The recommendations are based on a thorough review of the evidence and are intended to improve patient outcomes in the management of STEMI.
From the Research
Study Information
- The study that recommends a cut off point of 120 minutes for PCI is titled "Association of a Comprehensive ST-Segment-Elevation Myocardial Infarction Protocol With Key Process Metrics Among Patients Transferred for Primary Percutaneous Coronary Intervention" 2.
- This study, published in the Journal of the American Heart Association, found that achieving a door-to-balloon time (D2BT) of ≤120 minutes was associated with improved outcomes in patients with ST-segment-elevation myocardial infarction (STEMI) transferred for primary percutaneous coronary intervention (PCI).
- Key findings from this study include:
- Median D2BT decreased from 114 minutes to 97 minutes after implementation of a comprehensive STEMI protocol.
- The proportion of patients treated with D2BT of ≤120 minutes increased from 55.7% to 80.1% after protocol implementation.
- Achievement of D2BT <120 minutes was associated with a 50% relative risk reduction in the 30-day mortality rate.
Comparison with Other Studies
- Other studies, such as "The comparison of procedural and clinical outcomes of thrombolytic-facilitated and primary percutaneous coronary intervention in patients with acute ST-elevation myocardial infarction (STEMI): Findings from PROVE/ACS study" 3 and "Long-Term Outcomes of Pharmacoinvasive Strategy Versus Primary Percutaneous Coronary Intervention in ST-Elevation Myocardial Infarction: A Study from Mexico City" 4, have also investigated the outcomes of PCI in STEMI patients, but do not specifically recommend a cut off point of 120 minutes.
- A study titled "Primary Percutaneous Coronary Intervention and Application of the Pharmacoinvasive Approach Within ST-Elevation Myocardial Infarction Care Networks" 5 discusses the management of STEMI, including the importance of timely reperfusion therapy, but does not provide a specific cut off point for PCI.
- An older study, "Effectiveness of primary percutaneous coronary intervention compared with that of thrombolytic therapy in elderly patients with acute myocardial infarction" 6, compared the effectiveness of primary PCI with thrombolytic therapy in elderly patients with STEMI, but does not mention a specific cut off point of 120 minutes.