- What the 11 CHS Domains Actually Represent
- The 11 Content Areas, Domain by Domain
- How These Domains Show Up in the Written Exam
- Are the 11 Domains Weighted?
- Sequencing the Domains Into a Study Plan
- How the Domains Carry Into the Oral Examination
- Fees, Eligibility, and the Path to Sitting the Exam
- Frequently Asked Questions
- The CHS Part I written exam draws its content structure from 11 unweighted categories in the ABTS Booklet of Information.
- Written questions use three answer options, a format change ABTS introduced starting in 2025.
- Domains range from Septal Defects to Acquired Cardiovascular Diseases in Infants and Children - anatomy, physiology, and operative management all matter.
- Part I is computer-based at Pearson Professional Testing Centers; passing it is required before the in-person oral exam.
What the 11 CHS Domains Actually Represent
The Certification in Congenital Cardiac Surgery (CHS) credential, administered by the American Board of Thoracic Surgery (ABTS), organizes its Part I written examination content around 11 categories. These categories are reproduced from the ABTS 2025 Booklet of Information, and for planning purposes they should be treated as unweighted coverage areas rather than a fixed percentage breakdown. In other words, ABTS does not publish a domain-by-domain scoring weight - candidates should assume every category deserves solid preparation rather than trying to guess which ones carry more points.
If you are early in your planning, it helps to first understand the full arc of the credential - eligibility, cost, and timeline - before drilling into content. The CHS Requirements 2026 guide covers who is eligible to sit the exam in the first place, which matters because domain mastery only counts once you've cleared the training and case-volume thresholds.
The 11 Content Areas, Domain by Domain
Below is a breakdown of each domain with the kind of surgical and physiological reasoning candidates are expected to bring to test day. Because the categories are unweighted, treat this list as a checklist rather than a ranked priority order.
Domain 1: Septal Defects
Covers atrial septal defects, ventricular septal defects, and combined defects - including anatomic classification, shunt physiology, and timing of surgical closure.
- Distinguishing defect location and its impact on conduction risk
- Indications and timing for repair across age groups
Domain 2: Anomalies of Venous Connection
Encompasses anomalous pulmonary and systemic venous return, including partial and total anomalous pulmonary venous connection.
- Recognizing obstructed vs. unobstructed venous return
- Surgical approaches to rerouting venous drainage
Domain 3: Anomalies of the Aorta, Aortic Arch, and Coronary Arteries
Includes coarctation, interrupted arch, vascular rings, and coronary anomalies affecting surgical planning.
- Arch reconstruction techniques and staged approaches
- Coronary anomaly implications during other repairs
Domain 4: Anomalies of the Tricuspid and Mitral Valves
Covers congenital valve dysplasia, Ebstein anomaly, and mitral valve anomalies requiring repair or replacement strategies specific to pediatric anatomy.
- Valve-sparing repair techniques versus replacement
- Impact of atrioventricular valve disease on single-ventricle planning
Domain 5: Anomalies of the Aortic Valve and Left Ventricular Outflow Tract
Includes aortic stenosis, subvalvar and supravalvar obstruction, and left ventricular outflow tract reconstruction options.
- Ross procedure and valve-sparing considerations
- Balancing biventricular repair vs. staged palliation
Domain 6: Anomalies of the Pulmonary Valve and Right Ventricular Outflow Tract
Covers pulmonary stenosis/atresia and right ventricular outflow tract reconstruction, including conduit selection.
- Transannular patch vs. valve-sparing repair
- Long-term conduit durability considerations
Domain 7: Conotruncal Anomalies
Includes tetralogy of Fallot, truncus arteriosus, transposition of the great arteries, and double outlet ventricles.
- Arterial switch vs. Rastelli-type repairs
- Sequencing of staged repairs in complex conotruncal disease
Domain 8: Anomalies of Atrioventricular Connection, Univentricular Heart, and Atrial/Visceral Situs
Covers atrioventricular canal defects, single-ventricle physiology, heterotaxy, and situs abnormalities.
- Staged single-ventricle pathway (Norwood, Glenn, Fontan)
- Situs and connection nomenclature used in surgical planning
Domain 9: Diseases of the Myocardium
Includes cardiomyopathies and myocardial disease processes relevant to surgical decision-making in children.
- Indications for surgical intervention versus medical management
- Interaction between myocardial disease and mechanical support
Domain 10: Pre-, Intra-, and Post-Operative Evaluation and Management of Congenital Cardiac Disease
A broad perioperative domain spanning imaging interpretation, bypass strategy, and postoperative critical care decisions.
- Perioperative hemodynamic monitoring and troubleshooting
- Recognizing and managing early postoperative complications
Domain 11: Acquired Cardiovascular Diseases in Infants and Children
Covers non-congenital cardiac disease affecting pediatric patients, including infectious, inflammatory, and traumatic causes.
- Surgical management of acquired valve or myocardial disease
- Distinguishing acquired disease presentations from congenital mimics
Key Takeaway
Because ABTS does not publish domain weights, build a study rotation that gives each of the 11 domains dedicated review time rather than concentrating only on the most common lesions you see clinically.
How These Domains Show Up in the Written Exam
Part I of the CHS certification pathway is a multiple-choice written examination delivered at Pearson Professional Testing Centers. Starting in 2025, the written questions use three answer options rather than the traditional four or five - a format detail that changes how you should approach elimination strategy and time management during review. With fewer distractors per item, questions may lean more heavily on precise anatomic and physiologic distinctions within a domain rather than broad recall.
Passing the written exam is a prerequisite for advancing to the in-person Part II oral examination, so domain mastery at the written stage directly gates your path forward. For a deeper look at exactly how ABTS defines a passing result, see the CHS Passing Score 2026 guide.
Are the 11 Domains Weighted?
No official weighting is published for the 11 categories. They function as content coverage areas drawn from the ABTS Booklet of Information rather than a percentage-based blueprint. This has a practical implication for planning: instead of trying to reverse-engineer which domains appear most often, allocate study time based on your own clinical experience gaps. A cardiothoracic surgeon who has done extensive conotruncal repair work (Domain 7) may need comparatively less review there than in Diseases of the Myocardium (Domain 9) or Acquired Cardiovascular Diseases (Domain 11), which see less frequent operative exposure in many training pathways.
| Domain Group | Typical Candidate Familiarity | Study Emphasis |
|---|---|---|
| High-volume structural lesions (Domains 1, 6, 7) | Usually strong from case volume | Refresh nomenclature and edge-case variants |
| Valve and outflow tract anomalies (Domains 4, 5) | Variable, depends on subspecialty exposure | Deep review of repair-vs-replacement decision points |
| Single-ventricle and situs anomalies (Domain 8) | Often strong if fellowship-heavy in staged palliation | Sequence and staging logic across the pathway |
| Myocardial and acquired disease (Domains 9, 11) | Often lower exposure volume | Dedicated reading, since case exposure is naturally lower |
| Perioperative management (Domain 10) | Broad but easy to underestimate | Review imaging, bypass strategy, and critical care decision trees |
Sequencing the Domains Into a Study Plan
A structured schedule works better than open-ended review when you're covering 11 distinct content areas. Rather than a generic weekly template, map each block of time to the domains where your clinical exposure is thinnest, saving the last stretch before your test date for cumulative review across all 11 categories.
Foundational Structural Domains
- Septal Defects (Domain 1) and Venous Connection Anomalies (Domain 2)
- Aorta, arch, and coronary anomalies (Domain 3)
Valve and Outflow Tract Anatomy
- Tricuspid/mitral valve anomalies (Domain 4)
- Aortic valve and LVOT (Domain 5), pulmonary valve and RVOT (Domain 6)
Complex and Staged Anatomy
- Conotruncal anomalies (Domain 7)
- Atrioventricular connection, univentricular heart, and situs (Domain 8)
Lower-Exposure Domains and Perioperative Management
- Myocardial disease (Domain 9) and acquired disease (Domain 11)
- Pre-, intra-, and post-operative management (Domain 10)
For a fuller walkthrough of how to structure preparation across the full exam cycle - not just domain sequencing - see the CHS Study Guide 2026.
How the Domains Carry Into the Oral Examination
The 11 content categories don't disappear after the written exam - they resurface in case-based form during the in-person Part II oral examination. Where the written exam tests recognition and reasoning across discrete questions, the oral exam expects you to walk through operative decision-making live: how you'd approach a Domain 8 single-ventricle case from diagnosis through staged palliation, or how you'd manage a Domain 10 postoperative complication in real time.
Because the oral exam follows written success and represents a substantially larger portion of the total fee investment, it's worth understanding difficulty expectations for both stages together. The How Hard Is the CHS Exam? guide breaks down what makes each stage demanding, and how the two interact.
Fees, Eligibility, and the Path to Sitting the Exam
Domain preparation only matters once you've cleared the eligibility gate and budgeted for the process. Initial certification fees total $4,900, broken into a $650 application fee, $1,750 for the written examination, and $2,500 for the oral examination - before travel or study materials. Fellows starting on or after July 1, 2023 must complete two consecutive years in one ACGME-accredited program and log at least 150 major congenital cases, including at least 50 in the first year, along with unrestricted medical licensure and program endorsement.
If you haven't yet confirmed your eligibility timeline or fee planning, review the CHS Requirements 2026 and CHS Certification Cost 2026 guides before committing study hours to the 11 domains - there's little value in mastering Conotruncal Anomalies content months before you're even eligible to register.
Once you're ready to test your recall across all 11 categories under exam-like conditions, practicing with realistic three-option questions on our practice test platform is one of the most direct ways to see where domain gaps remain before you commit to the December 2026 written window.
Key Takeaway
Budget both time and money around the full pathway - eligibility, the $4,900 fee structure, and the written-then-oral sequence - before deep-diving into any single domain.
Frequently Asked Questions
No. ABTS presents them as content categories in the Booklet of Information without a published percentage weighting, so they should be treated as coverage areas rather than a scored blueprint.
There's no mandated order. A practical approach is to start with domains where your clinical case exposure is thinnest - often Diseases of the Myocardium (Domain 9) or Acquired Cardiovascular Diseases (Domain 11) - and finish with cumulative review across all 11.
Yes. The content areas span both stages: the written exam tests them through three-option multiple-choice questions, while the oral exam tests the same anatomic and physiologic knowledge through case-based discussion.
You can review domain-aligned practice questions and further breakdowns on our practice test site, and cross-reference exam logistics in the CHS Exam Dates 2026 guide.
These 11 categories are reproduced from the ABTS 2025 Booklet of Information. Always verify against the current live ABTS website before finalizing your study plan, since content descriptions can be updated between booklet editions.