afterload
The resistance against which the heart must work to eject blood during systole.
Full Definition
Afterload represents the force that the left ventricle must overcome to eject blood into the systemic circulation, primarily determined by systemic vascular resistance and arterial compliance. It can be approximated by systolic blood pressure but is more precisely measured as systemic vascular resistance. Increased afterload requires greater ventricular work and oxygen consumption, potentially leading to ventricular hypertrophy over time. Afterload reduction is a key therapeutic strategy in heart failure management, typically achieved through ACE inhibitors, ARBs, or vasodilators.
Usage
Usage note: Often confused with preload; ensure context clearly indicates systolic resistance.
In Context
- "ACE inhibitors reduce afterload by decreasing systemic vascular resistance." — Cardiovascular pharmacology guide
- "Elevated afterload in hypertensive patients increases cardiac workload significantly." — Clinical assessment report