Cardiac & circulatory nursing: ACS, heart failure, arrhythmias & shock

Cardiac items on a single-best-answer paper rarely ask you to name a disease. They give a short scenario and ask what the nurse does FIRST, what to assess, which finding to report, or which order to question. The safe answer is almost always the one that protects airway, breathing and circulation and catches a life-threatening change early.

A useful mental frame for chest-pain and cardiac scenarios:

• •ABC first — a patient who is unresponsive or not breathing needs CPR and the code team, not an ECG.
• •For a stable but symptomatic patient, oxygenation, a 12-lead ECG, IV access and continuous monitoring come before comfort measures.
• •'Report to the provider' answers win when a finding signals deterioration (new dysrhythmia, falling blood pressure, rising or new chest pain, potassium out of range on a digoxin patient).
• •When two answers both look reasonable, choose the one that ASSESSES before it acts, unless the scenario is a true emergency where acting (defibrillation, CPR) is the priority.

This note states widely accepted nursing principles. Drug doses and reference ranges vary by protocol; verify local orders and current guidance before applying any figure to a real patient.

The coronary arteries fill mainly during diastole. Anything that narrows them (atherosclerotic plaque) or raises myocardial oxygen demand (tachycardia, hypertension, exertion) can tip the balance so demand outstrips supply. The result is ischaemia; if flow is not restored, cells die (infarction).

Acute coronary syndrome (ACS) is an umbrella term for a sudden reduction in coronary blood flow, usually from plaque rupture and clot formation. It spans three overlapping presentations:

• •Unstable angina — ischaemic chest pain at rest or worsening in pattern, with NO rise in cardiac biomarkers and often no persistent ECG change.