- The Short Answer: What the Acronym Points To
- Which Credential This Site Means
- Who Issues the Certification
- What the Name Actually Covers: Heart, Lungs, Esophagus, Chest
- The Written Stage in Plain Numbers
- The Oral Stage and Its Case-Based Format
- The Ten Content Areas Behind the Name
- Eligibility and the ABTS Written-Exam Credit
- After You Pass: Maintenance and OCC
- Who Hires Certified Cardiothoracic Surgeons
- Sequencing Your Study Around the Blueprint
- Frequently Asked Questions
- This site's credential is Primary Certification in Cardiothoracic Surgery, issued by the American Osteopathic Board of Surgery (AOBS).
- The written exam is 200 multiple-choice questions over four hours 30 minutes, with a scaled passing score of 500 on 200-800.
- Cardiac & Cardiac Surgery (49-53%) and Thoracic (23-27%) together dominate the written blueprint.
- Written and oral fees are $1,500 each, totaling $3,000 on the standard path before other costs.
The Short Answer: What the Acronym Points To
When people search for what "Cardiothoracic Surgery" stands for, they are usually asking one of two things: what the words mean as a surgical discipline, or what credential carries that name. This article answers both, with the emphasis on the credential. Cardiothoracic surgery is the surgical specialty that treats diseases of the organs inside the chest: the heart, the great vessels, the lungs, the airway, the esophagus, and the mediastinum. The credential discussed here is Primary Certification in Cardiothoracic Surgery, awarded through the osteopathic certification system.
If you want the general definition first, our explainers on what cardiothoracic surgery is and the meaning of cardiothoracic surgery cover the clinical discipline in more depth. This piece stays focused on the certification: who runs it, what it tests, what it costs, and how the pieces fit together.
Which Credential This Site Means
The phrase "Cardiothoracic Surgery" appears in many places in medicine, and certification names can sound alike across boards. On cardiothoracicexam.com, the term refers to exactly one thing: Primary Certification in Cardiothoracic Surgery, which includes both a written stage and an oral stage. Every fact below, including fees, formats, content areas, and policies, belongs to that credential and no other.
For a broader orientation to the credential itself, see our overview of cardiothoracic surgery certification and the more direct explainer, what cardiothoracic surgery certification is.
Who Issues the Certification
Primary Certification in Cardiothoracic Surgery is issued by the American Osteopathic Board of Surgery (AOBS), operating with AOA certification approval. That makes it part of the osteopathic specialty-certification framework, which has its own application portal, its own board policies, and its own continuing-certification process, known as OCC.
Two practical consequences follow. First, the exam logistics you will meet, from remote proctoring instructions to application mechanics, run through AOA and AOBS systems. Second, the official exam-objective source is the AOBS "Cardiothoracic Surgery - Written Exam" content outline, which is the document you should treat as the authority on what is testable. Third-party summaries, including this one, should always be reconciled against it.
What the Name Actually Covers: Heart, Lungs, Esophagus, Chest
The two halves of the name map to two large clinical territories. "Cardio" covers the heart and great vessels: coronary disease, valvular disease, aortic pathology, congenital lesions treated surgically, heart failure surgery, and the perioperative management that surrounds all of it. "Thoracic" covers the rest of the chest: lung resection for malignancy, airway disease, pleural disease, chest wall problems, and the esophagus.
The exam blueprint reflects this split very clearly, and not evenly. The cardiac side carries roughly half of the written exam, while the thoracic side carries about a quarter. The remaining quarter is spread across smaller areas, including basic science, osteopathic manipulative medicine, trauma, and a category labeled "Other." A candidate who understands that distribution has an immediate advantage in deciding where hours should go.
The Written Stage in Plain Numbers
The written examination is the first formal hurdle, and its specifications are straightforward:
| Feature | Written Stage Detail |
|---|---|
| Question count | 200 multiple-choice questions |
| Time allowed | Four hours 30 minutes |
| Fee | $1,500 |
| Scoring | Scaled score; passing score is 500 on a 200-800 scale |
| Remote delivery | Follows AOA remote-proctoring instructions naming the MonitorEDU Secure Browser and PARADIGM testing |
Two details deserve attention. The scaled score means your raw number correct is converted, so do not try to reverse-engineer a raw cutoff; our guide to the cardiothoracic surgery passing score explains how to think about the 500 threshold. And because remote delivery depends on specific proctoring software, a technical check well before test day is part of preparation, not an afterthought. The AOA remote-proctored exams page is the place to confirm current requirements.
Pacing is worth planning arithmetically. Four hours 30 minutes across 200 questions leaves a bit over a minute per item on average, which is workable for single-best-answer questions but unforgiving if you linger on dense clinical stems. Practicing in timed blocks that mirror this ratio is more valuable than untimed review. When you are ready to rehearse, our cardiothoracic surgery practice tests are built for exactly that kind of timed work.
The Oral Stage and Its Case-Based Format
The second stage is oral. The fee is $1,500, and the format is criterion-referenced clinical cases. Examiners assess how you approach a patient problem: diagnosis, investigations, differential diagnosis, and management. Criterion-referenced means you are measured against a defined standard of competence rather than ranked against other candidates.
The published information does not give an oral question count or a timer, and this article will not invent one. What can be said is that the oral stage rewards a different skill than the written stage. Multiple-choice questions let you recognize a correct answer among options. Oral cases require you to generate the workup and the plan out loud, in a logical sequence, and to defend your reasoning when an examiner probes. Practicing by narrating a case aloud, from presentation through imaging, differential, operative choice, and complication management, is the closest rehearsal available.
The 2026 oral sitting was held on September 30 in person in New Orleans. Future sitting dates and locations should be confirmed on the AOBS oral-exam page and in current board notices, since they can change. For scheduling context, see our guide to cardiothoracic surgery exam dates.
The Ten Content Areas Behind the Name
The official written-exam content outline lists ten content areas, each with a published percentage range. These are the ranges as published, not normalized to sum to exactly 100, so they are best read as relative emphasis rather than exact question counts. A full walk-through lives in our guide to all ten content areas; here is the summary.
| Content Area | Published Range |
|---|---|
| Basic Science | 1-3% |
| Cardiac & Cardiac Surgery | 49-53% |
| Chest | 1-5% |
| Esophagus | 2-5% |
| Mediastinal (Mediastinum) | 1-4% |
| Osteopathic Manipulative Medicine | 1-3% |
| Other | 6-8% |
| Pulmonary | 2-6% |
| Thoracic | 23-27% |
| Trauma | 1-3% |
Cardiac & Cardiac Surgery (49-53%)
The center of gravity of the entire exam. Roughly half the written test sits here, so weakness in this area is difficult to offset elsewhere.
- Operative indications and timing across coronary, valvular, and aortic disease
- Perioperative physiology, including cardiopulmonary bypass concepts and postoperative management
- Complication recognition and management after cardiac operations
- Evidence-informed decision making when more than one reasonable strategy exists
Thoracic (23-27%)
The second pillar. It captures the non-cardiac chest surgery that defines the other half of the specialty's name.
- Staging and resectability reasoning for thoracic malignancy
- Selecting among resection approaches and managing their complications
- Pleural and airway problems that reach the thoracic surgeon
- Preoperative risk assessment and physiologic fitness for resection
The Smaller Areas That Still Count
Esophagus, Pulmonary, Chest, Mediastinal, Trauma, Basic Science, and Osteopathic Manipulative Medicine each carry modest weight individually, but together with "Other" (6-8%) they make up a meaningful share of the exam.
- Esophagus (2-5%) and Pulmonary (2-6%) reward concise command of core diagnostic and management logic
- Osteopathic Manipulative Medicine (1-3%) is a distinctive feature of this osteopathic certification and easy to neglect
- Trauma (1-3%) and Mediastinal (1-4%) favor focused, high-yield review rather than deep dives
Eligibility and the ABTS Written-Exam Credit
Eligibility requires approved training, an active unrestricted license, and the required documentation. The specialty page retains the traditional pathway language: four years of AOA-approved general surgery plus two years of cardiothoracic training, with program-director documentation. Current AOBS Board Policies also recognize qualifying DO/MD and ACGME routes, so the policies page is the place to see which route fits your own training history. Our requirements guide works through the prerequisites step by step.
A notable development came with the April 29, 2026 AOA announcement, which expanded AOBS certification eligibility. Under it, a passed ABTS written examination is recognized for the AOBS cardiothoracic oral-stage application. That is worth stating precisely:
Timing is the other area where candidates need to verify rather than assume. The specialty pages conflict on whether the application lead time is five or six months, and they retain April scheduling language, while the board homepage lists May 1-3, 2027 for the remote Spring Qualifying Examination. The Protocol for Certification is also under revision, so no current handbook is cited here. Treat the application portal and current AOBS notices as the final word on your individual deadlines, and build in buffer rather than working to the last day.
After You Pass: Maintenance and OCC
Certification is not a one-time event. The specialty timeline describes primary active status for one year, subject to OCC, the osteopathic continuing certification process. Maintenance involves several components:
- Licensure: an active license must be kept in good standing.
- CME: 60 credits per three-year cycle, confirmed by the current CME Requirements by Specialty Board document for 2025-2027.
- Longitudinal assessment: an annual assessment of 15 questions.
- Quality improvement: a QI/QA attestation every three years.
One caution: a page in the OCC materials carries legacy 10-year-cycle wording. That wording does not establish a new ten-year validity term, so do not plan around one. Follow the three-year CME and QI cycles as published.
If you fail, the rules are specific. Reapplication is required after a failure, and the written-exam page describes a two-year retake window after the first or second failure. After a third written or oral failure, documented board-review study is required before another written attempt. Knowing this up front is a good reason to prepare thoroughly the first time. Our difficulty guide and pass-rate discussion are candid about what is and is not known; notably, no AOBS cardiothoracic-specific pass rate has been verified, so be wary of any site quoting one.
Who Hires Certified Cardiothoracic Surgeons
Certification matters most in the settings where credentialing committees review board status. Hospital systems and academic medical centers with cardiac and thoracic surgery programs are the most common employers, along with large multispecialty groups and private cardiothoracic practices affiliated with hospitals. Regional medical centers that run heart programs, lung cancer programs, or both are frequent sources of openings.
Board certification typically appears in job postings as a requirement or a near-requirement, and it factors into hospital privileging and payer credentialing. Practice settings differ in their mix of cardiac and thoracic work, which is one reason the exam's heavy cardiac weighting and substantial thoracic weighting both matter: a surgeon may be asked to cover either side. We discuss the market in our pieces on cardiothoracic surgery jobs, salary, and the broader question of whether the certification is worth it. For the training side of the story, see cardiothoracic surgery training.
Sequencing Your Study Around the Blueprint
The blueprint suggests a sequencing logic: spend your most intensive weeks where the weight is, and use short, repeated passes for the small areas. A sample arrangement, to be adapted to your own timeline, might look like this:
Cardiac & Cardiac Surgery, first pass
- Coronary, valvular, and aortic operative indications
- Perioperative physiology and postoperative complications
- Take a timed block of questions at the end of each week
Thoracic
- Malignancy staging, resection selection, and risk assessment
- Pleural and airway problems
- Mix in Pulmonary content to reinforce physiology
Esophagus, Mediastinal, Chest, Trauma
- Concise review of each smaller area
- Include Osteopathic Manipulative Medicine and Basic Science so they are not skipped
Integration and oral rehearsal
- Second pass through Cardiac & Cardiac Surgery weak spots
- Narrate full cases aloud for oral-stage practice
- Run full-length timed simulations at the 200-question, 4:30 pace
The detailed methodology, resource selection, and review cadence are covered in our study guide, and a quick refresher for the final days is available in the cheat sheet. Do not postpone question practice until the end; using timed practice questions throughout the plan reveals weak domains while there is still time to fix them.
Key Takeaway
Let the published ranges set your hours. Roughly half your effort belongs to Cardiac & Cardiac Surgery, a quarter to Thoracic, and the rest to short, repeated passes through the eight smaller areas, including the osteopathic manipulative medicine content that is easy to overlook.
Frequently Asked Questions
It refers to Primary Certification in Cardiothoracic Surgery, issued by the American Osteopathic Board of Surgery (AOBS) with AOA certification approval. It includes a written stage and an oral stage. For a plain-language definition of the term, see what cardiothoracic surgery means.
The written exam has 200 multiple-choice questions to be completed in four hours 30 minutes. The scaled passing score is 500 on a 200-800 scale.
Cardiac & Cardiac Surgery, at 49-53%, is the largest, followed by Thoracic at 23-27%. The other eight areas, including Esophagus, Pulmonary, Trauma, and Osteopathic Manipulative Medicine, carry smaller ranges.
The written and oral fees are $1,500 each, which sums to $3,000 on the standard AOBS path, excluding other costs. Candidates receiving written-exam credit should confirm their fee path directly with AOBS.
No. A passed ABTS written examination is recognized for the AOBS cardiothoracic oral-stage application, which is credit within the AOBS pathway. It does not substitute an ABTS credential for AOBS Primary Certification in Cardiothoracic Surgery.