Chapter 24 Test — ECG in Pre-Hospital and Emergency Settings

A 58-year-old hypertensive smoker reaches the emergency department 90 minutes after the onset of crushing retrosternal chest pain radiating to the left arm, with diaphoresis and dyspnoea. Blood pressure is 132/80 mmHg with no features of cardiogenic shock. The 12-lead ECG shown was recorded within 8 minutes of arrival. The hospital has an on-site catheterisation laboratory with an expected delay to balloon inflation of 45 minutes. What is the most appropriate immediate reperfusion strategy?

A 68-year-old man with no prior cardiac history arrives in the emergency department with acute crushing chest pain and diaphoresis. His 12-lead ECG, shown here, has a QRS duration greater than 120 ms, a broad monophasic R wave in I, V5 and V6 with no preceding septal Q wave, a dominant S wave in V1, and discordant ST-T changes. No previous ECG is available for comparison. What is the MOST appropriate immediate management?

A 68-year-old man with diabetes, hypertension and hyperlipidaemia is transported to hospital by ambulance with crushing substernal chest pain. Emergency medical services personnel transmit a pre-hospital 12-lead ECG showing ST segments elevated more than 2 mm in multiple anterior leads. Which of the following electrocardiographic findings is LEAST likely in this patient?

A patient in an ambulance is unresponsive with the monitor attached. There is no palpable carotid pulse. The rhythm displayed is shown. What is the immediate action that should be taken?

A 60-year-old man with known coronary artery disease presents to the emergency department with palpitations and chest discomfort. His ECG shows a wide QRS complex tachycardia. Which of the following is NOT an ECG feature that would support this rhythm being ventricular tachycardia?

A 58-year-old man admitted two days ago with an inferior STEMI develops sudden hypotension (BP 80/60 mmHg) and oliguria. He is distressed with engorged jugular veins. Chest auscultation reveals clear lung fields. A repeat ECG shows ST elevation in leads II, III, aVF and V4R. Which is the most likely cause of his shock?

A 45-year-old man presents with progressive dyspnoea, muffled heart sounds, elevated JVP and hypotension. His ECG shows low voltage with electrical alternans. The chest X-ray shown demonstrates a markedly globular cardiac silhouette with bilateral basal opacities (blue arrows). Bedside echocardiography reveals a large circumferential anechoic collection compressing the right ventricle in diastole. What is the most likely diagnosis?

A 58-year-old hypertensive man presents to the emergency department with sudden-onset tearing chest pain radiating to the interscapular region. Blood pressure is 185/110 mmHg in the right arm and 145/90 mmHg in the left arm. His ECG is completely normal. The chest X-ray shown demonstrates a widened mediastinum. What is the most appropriate immediate next investigation?

A regional ambulance service equips its crews with 12-lead ECG machines and trains paramedics to transmit the tracing to the receiving hospital so the cath lab can be activated from the field. Compared with acquiring the first ECG only after the patient reaches the emergency department, what is the approximate reduction in door-to-balloon time achieved by this pre-hospital ECG programme?

A 61-year-old man walks into the emergency department triage desk at 09:00 complaining of chest tightness. Per ACC/AHA quality standards, by what time must his 12-lead ECG have been acquired?

A paramedic radios from a moving ambulance: the monitor is showing the tracing below and she is asking whether to defibrillate. The patient is sitting up, talking, and has a strong radial pulse at 80/min. What is the correct instruction?

A 47-year-old man is brought in after a collapse. The 12-lead ECG recorded by the ambulance crew is shown: in lead I the P wave, QRS and T wave are all inverted, aVR looks 'upright', and the precordial leads show entirely normal R-wave progression from V1 to V6. What is the most likely explanation?

A 62-year-old man presents to the emergency department with 40 minutes of chest pain. His 12-lead ECG shows horizontal ST depression of 2 mm in V1–V3 with tall R waves and upright T waves in those leads. There is no ST elevation anywhere on the standard 12 leads. What is the most appropriate immediate step?

A 64-year-old hypertensive man presents with severe chest pain that was maximal at onset and radiates through to his back. His ECG shows 2 mm of ST elevation in II, III and aVF. Blood pressure is 178/98 mmHg in the right arm and 150/84 mmHg in the left. The nearest PCI centre is 3 hours away and the team asks whether to give thrombolysis now. What should you do?

A 55-year-old man on maintenance haemodialysis has missed two sessions. He arrives lethargic and weak. His ECG shows tall, narrow-based peaked T waves with a QRS duration of 150 ms, as in the later panels of the figure shown. Blood samples have been sent but no results are back. What is the most time-critical next step?

A 58-year-old diabetic woman has ongoing central chest pain. Her ECG on arrival is completely normal and her initial high-sensitivity troponin is negative. She continues to have pain 20 minutes later. What is the most appropriate management?

A 52-year-old man arrives with breathlessness and hypotension (BP 84/56 mmHg). His JVP is elevated and his heart sounds are muffled. The 12-lead ECG shown demonstrates a tachycardia with small-amplitude QRS complexes whose height alternates from beat to beat. What is the most appropriate immediate action?

A 70-year-old woman presents with palpitations and mild breathlessness. Her ECG shows atrial fibrillation at 148/min. Blood pressure is 112/70 mmHg and she is not in pulmonary oedema. She cannot say when the palpitations began; she is not anticoagulated. What is the most appropriate management?

A 58-year-old man with a previous anterior myocardial infarction presents with palpitations. His ECG shows a regular monomorphic wide-complex tachycardia at 165/min. He is alert, with a blood pressure of 118/74 mmHg and no chest pain or pulmonary oedema. Which of the following is the most appropriate management?

A 44-year-old man with no cardiac risk factors is seen for 2 hours of atypical chest pain, now resolved. His ECG is normal and troponins at 0 and 3 hours are negative. His HEART score is 2. What is the most appropriate disposition, and what does his normal ECG contribute to that score?

A paramedic transmits a 12-lead ECG from the field on a 49-year-old man with 45 minutes of severe chest pain. It shows 1–3 mm of upsloping ST depression at the J point in V1–V4 with tall, symmetrical T waves in those leads, and no ST elevation. What does this pattern signify and what should be done?

A 66-year-old woman on sotalol presents with recurrent syncope. Her ECG between episodes shows a QTc of 540 ms, and the monitor captures repeated self-terminating runs of polymorphic ventricular tachycardia. She has a pulse throughout. Serum magnesium is 0.9 mmol/L (normal). What is the first-line treatment?

A 78-year-old man is brought in drowsy and hypotensive. The ECG shows P waves at 88/min marching independently of wide QRS complexes at 34/min, with no relationship between them. What is the immediate action required?

Which of the following pre-hospital actions is INCORRECT for a paramedic crew that has just recorded a field 12-lead ECG showing 2 mm of ST elevation in V2–V5 in a 55-year-old man with 40 minutes of chest pain?