EMT Cardiology – Cardiac Concepts & NREMT Exam Review

EMT Cardiology emergencies cover some of the most time-critical calls an EMT will run, from a patient clutching their chest to a full cardiac arrest requiring immediate CPR. This domain tests two closely related but distinct skill sets: recognizing and managing acute coronary syndrome (ACS) in a patient who still has a pulse, and running high-quality resuscitation when that pulse is gone. Both connect directly to what you’ve already covered in Studies like EMT Respiration and EMT Ventilation — cardiac and respiratory compromise show up together constantly, and a patient in cardiac distress is often also a patient struggling to breathe.

For further assisstance you can also visit EMT Comprehensive study guide.

Assessing a Cardiac Patient

Every suspected cardiac patient starts with the same structured history-taking, built on top of the [primary assessment] sequence:

• OPQRST — Onset, Provocation/Palliation, Quality, Radiation, Severity, Time — used specifically to characterize the chest pain itself: when it started, what makes it better or worse, what it feels like, where it spreads, how bad it is on a scale, and how long it’s been going on.
• SAMPLE history — Signs/symptoms, Allergies, Medications, Past medical history, Last oral intake, Events leading up to the complaint — gives broader context, including whether the patient already takes prescribed nitroglycerin, which matters directly for treatment decisions later.

To check your understanding of this topic specifically, try the EMT Cardiology practice quiz, or test it alongside the rest of the domain in the full EMT mock exam.

Signs and Symptoms of Acute Coronary Syndrome (ACS)

ACS doesn’t always present as textbook crushing chest pain. Common signs and symptoms include:

• Pain, pressure, or discomfort in the chest, jaw, neck, arms, or upper abdomen
• Difficulty breathing
• Palpitations
• Sudden onset of sweating and nausea or vomiting
• Syncope
• Anxiety or a sense of impending doom
• Unusual generalized weakness
• Abnormal pulse or blood pressure

On physical exam, watch for a patient grabbing or clutching the center of their chest, sweating, pale or gray skin, restlessness, or medic-alert jewelry indicating a known cardiac history. Because presentations vary so widely — some patients, particularly diabetics, older adults, and women, may present with atypical or minimal chest pain — the standard field approach is to treat any suspicious presentation as a possible myocardial infarction until proven otherwise, rather than waiting for a “classic” picture.

(Source: Studocu — Chapter 20: Cardiac Emergencies, Anatomy, ACS, and Treatment)

Treating ACS: Oxygen, Aspirin, and Nitroglycerin

At the EMT level, treatment for suspected ACS centers on three interventions, alongside prompt transport:

• Oxygen — considered as needed based on the patient’s respiratory status, using the same principles covered in [Ventilation].
• Aspirin — 324 mg (commonly given as chewable tablets) administered orally if cardiac ischemia is suspected and no contraindication exists. Chewing rather than swallowing speeds absorption. Aspirin is an antiplatelet agent — it reduces the ability of blood to clot, limiting the size of a forming coronary thrombus and helping preserve heart tissue. It’s generally withheld in patients with a known aspirin allergy or active bleeding disorder.
• Nitroglycerin — Given sublingually, typically 0.4 mg, and may be repeated up to three total doses roughly every 5 minutes, with a blood pressure check between doses. Nitroglycerin is a potent vasodilator that reduces both preload and afterload on the heart, lowering myocardial oxygen demand. Contraindications are heavily tested: hypotension (commonly cited threshold: systolic blood pressure below 90–100 mmHg, though exact local protocol values vary) and recent use of erectile dysfunction medications (phosphodiesterase inhibitors) within the prior 24–72 hours, because combining the two can cause a dangerous, severe drop in blood pressure. At the EMT level, an EMT typically assists a patient with their own prescribed nitroglycerin rather than carrying and administering it independently.

The definitive treatment for ACS is getting the patient to a facility capable of opening the blocked artery — meaning prompt transport, not prolonged on-scene intervention, is itself a core part of management.

(Sources: SDR Foundation — Cardiovascular Emergencies EMT Field Mastery Guide; MedicTests — Pharmacological Interventions During Chest Pain; 2bProtocols — Cardiac Chest Pain (ACS) Protocol)

12-Lead ECG at the EMT Level

An EMT’s role with a 12-lead ECG is limited but specific: placing the electrodes correctly on the chest, acquiring the tracing, and transmitting it to the receiving hospital to speed up definitive diagnosis. Interpretation of the ECG itself is outside the EMT scope of practice — that responsibility sits with paramedics, ALS providers, or hospital staff. Recognizing this scope boundary matters both clinically and for the exam, since EMT-level questions test what you do with the ECG (acquire and transmit), not how you read it.

(Source: Studocu — Chapter 20: Cardiac Emergencies)

Congestive Heart Failure and Pulmonary Edema

Cardiac and respiratory presentations overlap heavily in heart failure. Watch for dyspnea (especially orthopnea — difficulty breathing while lying flat), crackles or rales on lung auscultation from fluid backing up into the lungs, pedal edema, jugular venous distension (JVD), and pink, frothy sputum in more severe pulmonary edema. Management centers on positioning the patient sitting upright — not supine — along with oxygen via nonrebreather mask or CPAP if available and permitted by local protocol, connecting directly back to the oxygen delivery devices and CPAP use covered in [Ventilation].

(Source: Munden Interactive — EMT Cardiology Study Guide)

Cardiac Arrest and CPR

A patient in cardiac arrest is unresponsive, not breathing normally (absent or agonal breathing), and pulseless. Management follows a clear sequence: activate EMS/get help, begin immediate high-quality CPR, and apply an AED as soon as one is available — modern field protocols de-emphasize repeated pulse checks, since they waste time, are frequently inaccurate under stress, and interrupt compressions.

Adult CPR:

• Compression rate: 100–120 per minute
• Compression depth: 2–2.4 inches, allowing full chest recoil between compressions, with hand placement on the lower half of the sternum
• Compression-to-ventilation ratio: 30:2 for a single rescuer without an advanced airway
• Once an advanced airway is placed, compressions become continuous at 100–120/min with one breath delivered roughly every 6 seconds

Pediatric CPR:

• Compression rate remains 100–120 per minute across all age groups
• Compression depth: about 2 inches (roughly one-third of chest depth) for children, about 1.5 inches for infants
• Infant compressions use the two-thumb encircling-hands technique (two rescuers) or heel-of-one-hand technique (single rescuer); the two-finger technique is no longer recommended
• Pediatric patients under 8 years old should be defibrillated with pediatric AED pads/settings when available

AED use: Turn the device on, attach pads to bare, dry skin, and follow the voice prompts exactly. Clear the patient during rhythm analysis and shock delivery, and resume CPR immediately after a shock is delivered or after a “no shock advised” prompt — don’t delay compressions to reassess. If the presenting rhythm is ventricular fibrillation or pulseless ventricular tachycardia, immediate defibrillation is the priority intervention.

Common tested errors include delaying CPR or AED deployment, failing to recognize signs of hypoperfusion (shock) leading into arrest, giving aspirin or nitroglycerin when contraindicated, and incorrect patient positioning — for example, keeping a CHF patient supine rather than upright.

(Sources: AHA — What is CPR; ZOLL Medical — The Chain of Survival; CPR1 — CPR Compression Depth & Rate Explained; Munden Interactive — EMT Cardiology Study Guide)

Special Populations

Cardiac presentations, like airway and respiratory findings, shift with age and physiology — the same principle threaded through [Pediatric Assessment] and [Obstetric Emergencies]. Older adults are more likely to present with atypical ACS symptoms (weakness, confusion, or minimal pain rather than classic chest pressure), and pediatric cardiac arrest is far more often caused by a preceding respiratory problem than a primary cardiac event — which is why airway and ventilation management, covered in [Airway] and [Ventilation], stay central to pediatric resuscitation even in a cardiac arrest scenario.

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Continue Practice :- Emt Beginner quiz and Emt Intermediate quiz

Related Study Guide :- Emt Trauma Study Guide and Emt Resucitation Study Guide

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Key Points

• OPQRST characterizes the pain itself; SAMPLE gives broader patient context, including existing nitroglycerin prescriptions.
• Treat any suspicious presentation as a possible MI until proven otherwise — presentations vary widely, especially in older adults, diabetics, and women.
• Aspirin: 324 mg chewed, if no contraindication. Nitroglycerin: 0.4 mg SL, up to 3 doses, contraindicated in hypotension and recent ED medication use.
• EMTs acquire and transmit 12-lead ECGs; interpretation is outside EMT scope of practice.
• CHF/pulmonary edema: position upright, not supine; watch for JVD, crackles, and pedal edema.
• Adult CPR: 100–120 compressions/min, 2–2.4 inches deep, 30:2 ratio without an advanced airway.
• Pediatric CPR: same rate, shallower depth (2 in. children, 1.5 in. infants); two-thumb technique for infants.
• AED: follow prompts exactly, resume compressions immediately after shock/no-shock advisory.
• Pediatric cardiac arrest is usually secondary to a respiratory problem — airway and ventilation stay central even in a “cardiac” pediatric arrest.