The short answer
The RCIS is the cath lab credential — diagnostic catheterization, hemodynamics, and coronary intervention. The RCES is the EP lab credential — electrophysiology studies, ablation, and cardiac device therapy. Both are CCI registry credentials, both are 170-question exams with a 650-of-900 passing score. Take the one that matches where you work; take both if you cover both labs.
Side by side
| RCIS | RCES | |
|---|---|---|
| Lab | Cardiac cath lab | Electrophysiology (EP) lab |
| Core content | Hemodynamics, coronary anatomy, angiography, PCI, structural | Conduction system, EP studies, mapping, ablation, devices |
| Typical candidate | Cath lab tech / RN, crossover RT | EP tech / RN, device clinic staff |
| Format | 170 questions, 3 hours, $365 | 170 questions, 3 hours, $365 |
| Passing score | 650 scaled (0–900) | 650 scaled (0–900) |
What each one actually covers
The RCIS lives in the cath lab: reading hemodynamic waveforms and running the calculations, coronary anatomy and angiographic projections, PCI equipment and technique, structural interventions, and the emergencies and pharmacology around them.
The RCES lives in the EP lab: the conduction system and baseline intervals, diagnostic pacing and arrhythmia mechanisms, catheter ablation targets (such as pulmonary vein isolation and the cavotricuspid isthmus), 3D electroanatomical mapping, and cardiac rhythm management devices — pacemakers, ICDs, and CRT.
Which should you take?
Simplest rule: earn the credential for the lab you work in. Cath lab staff take the RCIS; EP lab and device-clinic staff take the RCES. If you float between both — as many cardiovascular professionals do — the two credentials together document the full scope of your work.
Should you do both?
Plenty of people hold both. The content overlaps in the foundations — cardiac anatomy, vascular access, pharmacology, and lab emergencies apply to either exam — so once you have prepared for one, the shared ground makes the second less of a leap. Cardiac Codex was built to cover both blueprints in one place for exactly this reason.
Is one harder than the other?
Structurally they are the same exam length, time, and pass bar, so difficulty is individual. EP content is more conceptually abstract (timing, circuits, and mechanisms); cath content is more hemodynamics- and math-heavy. Whichever is further from your daily work will feel harder — that is the one to weight your study toward.
Study both blueprints in one place
Cardiac Codex covers the full RCIS and RCES blueprints — lessons, practice questions, and mock exams for both. Try the free questions for either credential first.
Try free RCIS questions The RCIS Exam: Complete 2026 Guide →Frequently asked
Is RCIS or RCES harder?
Neither is inherently harder — both are 170-question exams with the same 650-of-900 pass bar. Difficulty is individual: EP content is more abstract, cath content is more hemodynamics-heavy, so whichever is further from your daily work feels harder.
Can you hold both RCIS and RCES?
Yes. Many cardiovascular professionals hold both credentials, and the shared anatomy, pharmacology, access, and emergency content makes preparing for the second easier once you have done the first.
Do RCIS and RCES content overlap?
Yes. Cardiac anatomy, vascular access, pharmacology, and lab emergencies apply to both. The core difference is cath lab hemodynamics and coronary intervention (RCIS) versus electrophysiology, ablation, and devices (RCES).