What are the time-sensitive treatment goals for acute ischemic stroke and acute myocardial infarction (AMI), including 'door to needle' time for thrombolytic therapy with alteplase (tissue plasminogen activator) and 'door to balloon' time for primary percutaneous coronary intervention (PCI) from first medical contact?

Time-Sensitive Treatment Goals for Acute Ischemic Stroke and Acute Myocardial Infarction

For acute ischemic stroke, the primary door-to-needle time goal is ≤60 minutes in ≥50% of patients receiving IV alteplase, with an aspirational secondary goal of ≤45 minutes in ≥50% of patients; for acute myocardial infarction, the door-to-balloon time goal is ≤90 minutes for primary PCI, and door-to-needle time is ≤30 minutes for fibrinolytic therapy. 1

Acute Ischemic Stroke: Door-to-Needle Time Goals

Primary Recommendations

• The American Heart Association/American Stroke Association establishes a Class I recommendation that door-to-needle (DTN) times should be ≤60 minutes in ≥50% of acute ischemic stroke patients treated with IV alteplase. 1

• A more aggressive secondary goal of achieving DTN times ≤45 minutes in ≥50% of patients is reasonable (Class IIb recommendation). 1

• The Canadian Stroke Best Practice Recommendations set an even more ambitious target: DTN time <60 minutes in 90% of treated patients, with a median DTN time of 30 minutes. 1

Evidence Supporting Faster Treatment

• Every 15-minute reduction in door-to-needle time translates to a 5% lower odds of in-hospital mortality (adjusted OR 0.95% CI 0.92-0.98). 1

• Treatment within 30 minutes of arrival is associated with significantly better post-treatment modified Rankin Scale scores, improved NIHSS scores, and reduced length of stay compared to treatment within 45 or 60 minutes. 2

• Real-world data from 2014-2015 showed that 59.3% of patients received IV alteplase within 60 minutes, with a median DTN time of 56 minutes (interquartile range 42-75 minutes). 1

Treatment Window from Symptom Onset

• IV alteplase should be administered within 3 hours of symptom onset (Class I, Level A recommendation), with extension to 4.5 hours for selected patients (Class I/IIa, Level B recommendation). 1

• Treatment beyond 4.5 hours requires consultation with a stroke specialist and remains investigational. 1

Acute Myocardial Infarction: Time Goals

Primary PCI (Door-to-Balloon Time)

• For patients transported by EMS to a PCI-capable hospital, the goal is EMS arrival-to-balloon time ≤90 minutes. 1

• For patients who self-transport to a PCI-capable hospital, the door-to-balloon time goal is ≤90 minutes. 1

• These represent maximum acceptable times, not ideal times—systems achieving faster times (median 60-70 minutes) should be encouraged. 1

Fibrinolytic Therapy (Door-to-Needle Time)

• For patients transported to non-PCI-capable hospitals where fibrinolysis is indicated, the door-to-needle time goal is ≤30 minutes. 1

• If EMS has fibrinolytic capability, prehospital fibrinolysis should be initiated within 30 minutes of EMS arrival on scene. 1

First Medical Contact Considerations

• The overarching goal is to keep total ischemic time within 120 minutes (ideally within 60 minutes) from symptom onset to initiation of reperfusion treatment. 1

• "First medical contact" is defined as either the time of EMS arrival on scene (when patient calls 911) or time of arrival at the emergency department door (when patient self-transports). 1

Critical Implementation Strategies

For Stroke Systems

• EMS prenotification is essential and associated with shorter door-to-imaging times (26 vs 31 minutes), shorter DTN times (78 vs 80 minutes), and increased likelihood of treatment within 3 hours. 1

• Multicomponent quality improvement initiatives including ED education and multidisciplinary teams with neurological expertise are strongly recommended (Class I, Level A). 1

• The key to achieving 20-minute median DTN times is doing as little as possible after patient arrival and as much as possible before arrival during transport. 3

For AMI Systems

• Prehospital 12-lead ECG programs by EMS providing advanced life support are underutilized but effective strategies for improving systems of care. 1

• Transfer protocols must be in place for arranging rescue PCI when fibrinolysis is unsuccessful. 1

Common Pitfalls to Avoid

• Do not perform extensive diagnostic workup that delays treatment—brain imaging to rule out hemorrhage is the only essential test before alteplase administration. 4, 5

• Do not administer aspirin or other antithrombotic agents before brain imaging rules out hemorrhagic stroke. 4

• Performing angiography or perfusion imaging doubles in-hospital delays and should not delay alteplase administration in eligible patients within the standard treatment window. 3

• Do not aggressively lower blood pressure in suspected ischemic stroke patients who may be candidates for thrombolytic therapy unless BP exceeds specific thresholds (systolic >220 mmHg or diastolic >120 mmHg). 4, 5

• For AMI, the emphasis on primary PCI should not obscure the importance of fibrinolytic therapy when PCI cannot be achieved within the 90-minute goal. 1