Immediate Management of Heart Attack in an Outpatient Setting
Call 9-1-1 immediately and do not attempt to transport the patient yourself—activate emergency medical services (EMS) to ensure rapid access to defibrillation, advanced cardiac life support, and hospital-based reperfusion therapy. 1
Critical First Actions (Within 5 Minutes)
If the patient is experiencing chest discomfort or anginal equivalents (shortness of breath, cold sweat, nausea, lightheadedness) for more than 5 minutes that is unimproved or worsening, call 9-1-1 immediately. 1
Immediate Medication Administration While Awaiting EMS
Administer aspirin 160-325 mg orally (chewable preferred) immediately unless there is a known allergy or active bleeding contraindication 1, 2, 3
Give sublingual nitroglycerin if the patient has been previously prescribed it and their systolic blood pressure is ≥90 mmHg and heart rate is between 50-100 bpm 1, 2
Administer oxygen via nasal prongs if available, especially if the patient appears breathless or has signs of heart failure 1, 2
Provide adequate analgesia with intravenous morphine (4-8 mg initially, with additional 2 mg doses at 5-minute intervals) if you have the capability and training, along with an antiemetic 1, 2
Critical Timing for Nitroglycerin Use
For patients without previously prescribed nitroglycerin: Do not seek someone else's nitroglycerin—focus solely on calling 9-1-1 if chest discomfort is unimproved or worsening 5 minutes after onset 1
For patients with chronic stable angina who have been prescribed nitroglycerin: If symptoms are significantly improved after one dose, it is appropriate to repeat nitroglycerin every 5 minutes for a maximum of 3 doses, but call 9-1-1 if symptoms have not totally resolved 1
What NOT to Do: Common Pitfalls
Do not delay calling 9-1-1 to administer multiple doses of nitroglycerin or to "wait and see" if symptoms improve—patient delay is the longest component of treatment delay and occurs during the most critical time 1
Do not transport the patient to the hospital yourself—EMS personnel can provide defibrillation, advanced life support, and pre-hospital ECG interpretation en route 1
Do not wait for the patient's regular physician to arrive—general practitioners should immediately call for an ambulance unless they can respond within minutes and are trained in advanced cardiac life support, ECG interpretation, and administration of opioids and fibrinolytic drugs 1
Do not encourage patients to take aspirin before calling 9-1-1—this has been associated with delays in activating EMS; the priority is calling 9-1-1, after which emergency dispatchers can instruct aspirin administration 1
Why Time Is Critical
The greatest benefit of reperfusion therapy occurs within the first hour ("golden hour"), saving 35 lives per 1,000 patients treated, compared to only 16 lives per 1,000 when treated between 7-12 hours after symptom onset. 4, 2
- Treatment within the first hour saves 65 lives per 1,000 patients 1
- Treatment in the second or third hour saves 27 lives per 1,000 patients 1
- Reperfusion therapy beyond 12 hours offers little benefit in most patients 1, 4
Patient Characteristics Requiring Immediate ED Referral
Patients with suspected acute coronary syndrome should be referred immediately to an emergency department or specialized chest pain unit if they have: 1
- Chest discomfort or ischemic symptoms at rest for more than 20 minutes
- Hemodynamic instability
- Recent syncope or presyncope
Role of the Outpatient Provider
General practitioners must develop practice policies for responding rapidly to patients with chest pain, including educating ancillary staff and establishing protocols for appropriate administration of oxygen, nitrates, and aspirin. 1
Where feasible, arrange to rendezvous with an emergency ambulance at the patient's location, but only if this does not cause additional delay for the patient. 1
Equipment That Should Be Available
- Defibrillator (all emergency responses for chest pain require a vehicle with a defibrillator and staff trained in its use) 1
- Oxygen delivery system 1, 2
- Aspirin (160-325 mg tablets) 1, 2
- Sublingual nitroglycerin 1, 2
- Intravenous morphine or diamorphine with antiemetic 1, 2
- Emergency drugs including adrenaline, atropine, lignocaine, frusemide, and naloxone 1
Target Time Goals
The "call to needle time" (from alerting medical services to receiving thrombolytic treatment) should be within 90 minutes, with 60 minutes as the ideal target. 1, 2
Once EMS is activated, the patient's general practitioner should be informed when feasible, particularly in areas where integrated response by general practitioners, ambulance services, and hospital staff is required. 1