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Posterior Descending Artery (PDA)

A Cath Lab Anatomy & Hemodynamics term on the RCIS exam blueprint, defined for cath lab and EP clinicians.

In right-dominant systems (80% to 85% of cases), the RCA continues around the crux of the heart to give rise to the PDA, which supplies the inferior third of the interventricular septum and posterolateral branches.

Anterior view of the heart marking the crux, where in right-dominant systems the right coronary artery continues as the posterior descending artery supplying the inferior septum and posterolateral branches.
The crux, and why the PDA’s origin is what defines dominance.

Domain: Cath Lab Anatomy & Hemodynamics · Blueprint: RCIS exam guide

Related RCIS terms

Atrioventricular (AV) Node Bundle Branches Left Anterior Descending (LAD) Artery Left Circumflex (LCX) Artery Left Main Coronary Artery (LMCA)

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Written and reviewed by John-Philip (JP) Maarschalk, BSN, RN, CNML — a nurse manager who runs operations for the cardiac cath lab, electrophysiology, and interventional service lines at an academic health system in North Carolina. He hires and develops the staff who sit for these exams. More about JP and how this content is made →
Cardiac Codex is an independent study tool published by MdoubleA LLC, not affiliated with or endorsed by CCI or any certifying body. This glossary entry is exam-preparation information, not medical advice or a substitute for clinical judgment. Always verify current clinical practice against primary sources and institutional protocol.