What it is
Cardiac afterload is the outlet load the ventricle must push against to eject blood into the arterial system.[1,2]
Why it matters
Higher afterload makes ejection harder, so the same contraction may eject less blood unless the heart compensates.[1]
Root causes of abnormal values
- Outlet-load relation: Higher arterial pressure or vascular resistance increases the load the ventricle must overcome and can lower stroke volume; lower outlet load lets the same contraction eject more easily.[1,2,3]
What it affects
- It connects blood pressure, vascular resistance, arterial load, stroke volume, and pump reserve.[1,3]
Interpretation traps
- Afterload is not identical to a single cuff blood-pressure reading, though arterial pressure is a major part of the load.[2,1]