What should you know about acute diastolic heart failure?

During diastole, the heart muscle relaxes so its chambers can fill. If the left ventricle is stiff or does not relax properly, it needs higher pressure to fill. That pressure can travel back toward the lungs, allowing fluid to collect there. A person may develop sudden breathlessness, difficulty lying flat, cough, fatigue or ankle swelling even when the heart's squeezing strength is preserved.

An episode may be brought on by very high blood pressure, an abnormal rhythm such as atrial fibrillation, infection, a heart blood-flow problem, kidney dysfunction, excess salt or fluid, or missed medicines. Clinicians may use the broader term acute heart failure with preserved ejection fraction, although the exact diagnosis depends on examination and testing.

Assessment commonly includes oxygen level, blood pressure, heart rhythm, blood tests, a chest image and an echocardiogram. Treatment is tailored to the findings. It may include oxygen when the blood oxygen level is low, a diuretic to remove excess fluid, treatment to lower dangerously high blood pressure, and care for a trigger such as an abnormal rhythm or infection.

After stabilisation, take prescribed medicines exactly as directed and follow the agreed plan for salt, fluids and daily monitoring. Record new breathlessness, swelling or rapid weight change and contact the treating team promptly if they appear. Do not take an extra diuretic unless the clinician has provided a specific adjustment plan.

Call emergency services for severe or rapidly worsening breathlessness, breathlessness at rest, blue or grey lips, fainting, confusion, chest pressure, or coughing up pink frothy fluid. Sit upright while waiting if that makes breathing easier, and do not drive yourself when symptoms are severe.

Seek same-day medical advice for a clear increase in ankle swelling, new difficulty sleeping flat, worsening cough, marked fatigue or palpitations, especially after a recent heart-failure admission or medicine change. These changes can signal returning congestion or a new trigger and should be assessed before they escalate.

Ask what triggered the episode, whether the echocardiogram showed preserved squeezing function, what your target weight and blood pressure should be, and which symptom changes should prompt a call. Clarify whether you need limits on salt or fluids, how to respond to a missed dose, and when kidney function and electrolytes will be rechecked.