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Level 1Beginner Clinical Topics

Shortness of Breath Basics

Heart and non-heart causes of breathlessness, what patients describe, and the red flags.

Beginner~14 min

Learning Objectives

  • 1.List heart and non-heart causes of shortness of breath.
  • 2.Recognize the heart-failure pattern of breathlessness.
  • 3.Identify the red flags that mean call 911.

Overview

Shortness of breath ("dyspnea") means trouble breathing or not getting enough air. It can come from the heart, the lungs, or other causes — and how severe it is matters most.

What it can mean

  • •Heart: heart failure (fluid backing into the lungs) or a heart attack.
  • •Lungs: asthma, COPD, pneumonia, or a blood clot (PE).
  • •Other: anemia, anxiety, or being out of shape.

What patients say (heart-failure clues)

  • •"I can’t catch my breath walking."
  • •"I can’t lie flat — I need extra pillows" (orthopnea).
  • •"I wake up at night gasping."
  • •With swollen legs and weight gain.

What clinicians worry about

  • •How severe is it right now (can they speak in full sentences?), and is it from the heart (heart failure/heart attack) or the lungs (clot, severe asthma/COPD)?

Basic workup

  • •Oxygen level, an EKG, a chest X-ray, and blood tests (like BNP for heart failure) help sort it out.

Red flags — call 911

  • •Too short of breath to speak in full sentences.
  • •Blue lips or fingertips.
  • •Sudden severe breathlessness, especially with chest pain.

Emergency

Severe trouble breathing is an emergency — get help immediately.

A simple case

A patient with a weak heart is gaining weight, swelling in the legs, and now sleeps sitting up because lying flat makes him breathless.

What does this sound like?

Show answer

Heart failure — fluid is backing up into the lungs and legs. The "can’t lie flat" and weight gain are classic. This person needs to be seen promptly.

Knowledge Check Quiz

Disclaimer: This content is for educational purposes only. It is not medical advice, does not replace clinical judgment, and is not a substitute for institutional protocols or certified medical interpreters. No patient health information (PHI) should be entered into this application.