About Cardiac Codex — Who Writes This, and Why

The person behind it

John-Philip “JP” Maarschalk, RN, CNML

Founder, Cardiac Codex

Nurse Manager, Operations — cardiac catheterization, electrophysiology, interventional radiology, and neurointerventional services
Academic health system, North Carolina
Certified Nurse Manager and Leader (CNML)
Former Senior Special Forces Medical Sergeant, U.S. Army Special Operations

JP Maarschalk is a nurse manager who leads operations for cardiac catheterization, electrophysiology, interventional radiology, and neurointerventional services at a large academic health system in North Carolina. His work centers on procedural performance, patient safety, and building teams that can sustain high-acuity work.

He also hires, onboards, and develops the cath lab and EP staff who sit for the RCIS and RCES exams — which is the reason Cardiac Codex exists. He kept watching capable people, staff who could run a complex case cold, struggle with an exam that tests that same knowledge in an unfamiliar format. The gap was never clinical ability. It was the translation between doing the work and being tested on it.

Before moving into healthcare leadership, JP served as a Senior Special Forces Medical Sergeant with U.S. Army Special Operations and the North Carolina National Guard. That background shaped how Cardiac Codex teaches: start from the mechanism, drill until recall is automatic, and never mistake familiarity with a subject for competence in it.

To be explicit about credentials: JP is a registered nurse and a Certified Nurse Manager and Leader. He does not hold the RCIS or RCES credential. The experience Cardiac Codex is built on is operational and clinical — running these labs and developing the people in them — not personally holding the certification you are studying for. Every exam-specific fact on this site is sourced from CCI's own published materials rather than from recollection.

Why this exists

The RCIS and RCES are unusual exams. They test a body of knowledge that competent technologists and nurses already use every shift — hemodynamics, pharmacology, radiation physics, arrhythmia recognition, device function — but they test it in a format that has almost nothing in common with how the work actually feels.

Someone who can recognize tamponade physiology on a waveform in the room, in real time, with a patient decompensating, will still miss the multiple-choice version of that question if they have only ever met the concept through pattern recognition and never through mechanism. That is a translation problem, not a knowledge problem, and it is solvable.

So Cardiac Codex is built around three commitments:

Start from mechanism. If you understand why the waveform does that, you can answer a question you have never seen before. Memorized patterns only answer questions you have.
Use the language of the lab. The explanations sound like a good preceptor talking you through a case, because that is who wrote them.
Be honest about the exam. The format, the blueprint weightings, the eligibility pathways, and the cost are all published by CCI. We report them accurately and cite the source, and we tell you when something has changed.

How the content is made

Transparency about process matters more in exam prep than in almost any other category, because a confident wrong answer costs someone a $365 exam attempt and months of study. Here is how this works:

Element	How it is handled
Exam facts	Sourced only from CCI's published materials at cci-online.org. Each guide page carries the date those facts were verified. We do not repeat exam facts we find on other prep sites — several of them are wrong.
Clinical explanations	Written against standard cardiovascular and electrophysiology references, then checked for how the concept is actually used and taught in the lab.
Practice questions	Written originally, against the published CCI content blueprint. No recalled, leaked, or reconstructed live exam items are used, solicited, or accepted — ever. Sharing real exam content violates CCI's candidate agreement and can cost someone their credential.
Corrections	If something here is wrong, we want to know and we will fix it and say that we did. Corrections go to the address below.
Use of AI	We use AI deliberately, and we will always tell you where. In the app, Cardiac Coach answers your questions using retrieval over our own lessons and glossary rather than generating freely — and it tells you when a topic isn't in the curriculum instead of inventing an answer. On the written side, AI helps draft, structure, and check consistency across a large body of material. What AI does not do here is decide what is clinically true. Every clinical claim and every exam fact is reviewed by a human with cath lab and EP experience before it publishes. Nothing publishes unreviewed.

What we do not claim

A lot of exam prep marketing makes promises it cannot support. For the record, here is what Cardiac Codex will not tell you:

We are not affiliated with CCI. Cardiac Codex is not affiliated with, endorsed by, sponsored by, or administered by Cardiovascular Credentialing International. CCI writes and owns the RCIS and RCES exams. We are an independent study resource, and we are not a CCI-approved or CCI-recognized provider.
We do not guarantee a passing score. No study resource can, and any that says otherwise is selling you something. We do not publish a pass-rate claim for our own users, because we do not yet have the data to support one honestly.
We do not publish testimonials we cannot verify, and we do not publish any learner's name, quote, result, or workplace without their written consent.
This is not clinical advice. Everything here is exam-preparation material for credentialed and credentialing professionals. It is not guidance for treating a patient.
We do not speak for any employer. Cardiac Codex is an independent project published by MdoubleA LLC. It is not affiliated with, endorsed by, or sponsored by any hospital, health system, or employer. Views expressed here are JP's own.

Get in touch

Corrections, questions about the exams, or a request for something we have not covered yet — all welcome. Content requests from people actually sitting for these exams are the single most useful input we get, and they drive what gets written next.

[email protected]

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More from Cardiac Codex

Cardiac Codex is an independent study tool published by MdoubleA LLC. It is not affiliated with, endorsed by, or administered by Cardiovascular Credentialing International (CCI) or any certifying body, and completing any study material does not guarantee a passing score. Always confirm current requirements, fees, and blueprints directly with CCI at cci-online.org. This page is exam-preparation information, not medical advice.

Who writes this, and why