Cardiology
Heart failure
Written 30 September 2026. This date is not a physician-review date.
Why this matters
Breathlessness has many causes. Heart failure is a syndrome of congestion, perfusion, or both — not a single drug list.
Rapid clinical summary
- Ask whether the patient is wet, cold, or both.
- A sudden weight rise in known heart failure is congestion until proved otherwise.
- Not every crackle is heart failure, and not every heart failure patient has crackles.
Mechanism
The ventricle fails to deliver output at a normal filling pressure. Pressure backs up into lungs or veins. Compensatory vasoconstriction can preserve blood pressure while the patient is still under-perfused.
Recognition
Wet means congestion. Cold means poor perfusion. The combination changes the urgency.
Typical
- Orthopnea
- Paroxysmal nocturnal dyspnea
- Edema
- Weight gain
- Fatigue
Red flags
- Shock
- Hypoxia with exhaustion
- A new murmur and pulmonary edema
- Chest pain with the edema
Differential
| Condition | Clue | Trap |
|---|---|---|
| COPD exacerbation | Wheeze, known smoking disease, little edema | Treating every wheeze as failure, or every failure as wheeze |
| Pneumonia | Fever, focal signs | Missing infection as the reason failure suddenly worsened |
| Pulmonary embolism | Sudden dyspnea, clear lungs, a risk | Diuresing a patient whose problem is clot |
| Nephrotic edema | Heavy proteinuria, less orthopnea | Assuming all edema is cardiac |
Investigations
- ECG, because the rhythm and a territorial pattern change management.
- A chest radiograph looks for edema and for the alternatives.
- Natriuretic peptides support the syndrome when the diagnosis is uncertain. They do not replace the examination.
Management
- Immediate
- If the patient is hypoxic or shocked, that is an emergency airway and perfusion problem. If they are wet and warm, the immediate issue is congestion.
- Definitive
- Remove the trigger, relieve congestion, and continue disease-modifying treatment when it is safe. Doses are not stated on this page.
- Monitoring
- Daily weight, symptoms, and renal function and potassium when diuretics or renin–angiotensin drugs change. A rising creatinine needs a reason, not an automatic stop of every drug.
Common pitfalls
- Ignoring a 3 kg weight gain because blood pressure is normal.
- Stopping all cardiac drugs because of mild dizziness.
- Missing ischemia as the cause of new pulmonary edema.
Exam reasoning
Questions separate congestion from poor perfusion, and a decompensation from a stable chronic plan.
Practice this topicOpens original Mahazanaka questions in this subject. If this subject is thin on that track, the session uses what exists.
Visual summary
Congestion and perfusion are separate questions.
Recognize, reason, prioritize, act safely
- Recognize. Congestion, a perfusion problem, or both.
- Reason. What changed this week?
- Prioritize. Shock and hypoxia before a clinic conversation about long-term drugs.
- Act safely. Reassess. Do not ‘continue unchanged’ through new edema.
Knowledge check
Known heart failure, 3 kg heavier, new ankle swelling, still talking, not hypotensive. What is the mistake in waiting for the next routine visit?
No citation is attached to this chapter. Nothing here is personal medical advice.