CardioNerds (Drs. Rawan Amir, Tripti Gupta, and Alysha Joseph) discuss the fundamentals of adult congenital heart disease (ACHD) surgery with Dr. Elizabeth Stephens. Audio editing by CardioNerds academy intern, Grace Qiu.

Using a case of a young adult undergoing a Ross procedure, the episode walks through what happens in the operating room—from induction and intraoperative transesophageal echocardiography (TEE) to cardiopulmonary bypass (CPB), myocardial protection, and surgical repair. The discussion highlights key concepts including cardioplegia, cross-clamp and bypass times, hypothermic circulatory arrest, and the complexity of redo sternotomy. This episode provides learners with a practical framework to interpret operative reports, anticipate postoperative physiology, and better collaborate with surgical teams.

This episode was produced by the CardioNerds ACHD Council and planned by Dr. Rawan Amir.

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Pearls

“LV distension kills patients.”
Preventing left ventricular distension with appropriate venting and awareness of aortic insufficiency is critical to intraoperative safety.
TEE can change the surgical plan in real time.
Findings such as underestimated aortic regurgitation, mitral pathology, or a PFO may directly alter cannulation and cardioplegia strategy.
Cross-clamp time = myocardial ischemic time; bypass time = systemic stress.
Both are key predictors of postoperative complications including renal injury, bleeding, and ventricular dysfunction.
Redo sternotomy risk is driven by anatomy, not just number.
Aorta adherent to the sternum, conduit position, and chamber pressurization define risk more than the number of prior surgeries.
Think longitudinally—ACHD surgery is lifetime planning.
Surgical materials and strategies must account for future interventions, especially in younger patients.

Notes:

Notes drafted by Dr. Alysha Joseph, aided by generative artificial intelligence.

What are the key steps in congenital cardiac surgery from incision to closure?

Preoperative planning is multidisciplinary, involving surgeon, anesthesia, cardiology, and ICU teams; high-risk inductions (e.g., critical AS, Williams syndrome) are identified early
TEE is performed immediately after induction to reassess anatomy and may reveal new findings (e.g., underestimated AI, mitral disease, PFO)
Median sternotomy is performed, followed by creation of a pericardial well to optimize exposure
Heparin is administered prior to cannulation; arterial and venous cannulas are placed for initiation of CPB
Cross-clamp is applied and cardioplegia delivered to arrest the heart, allowing a still and protected operative field
Surgical repair (e.g., Ross procedure) is performed, followed by de-airing, cross-clamp removal, and reperfusion
Patient is weaned from bypass with TEE reassessment, hemostasis achieved, and chest closed

What is cardioplegia and how is it delivered?

Cardioplegia is a potassium-rich solution that arrests myocardial activity and reduces metabolic demand
Most commonly used solution in the U.S. is Del Nido cardioplegia, originally developed for pediatric myocardium
Delivery strategies include:

Antegrade (via aortic root) – standard approach
Ostial (direct coronary delivery) – used when aortic root cannot be relied upon
Retrograde (via coronary sinus) – useful in severe AI or coronary disease

NOTE: Severe aortic regurgitation can impair antegrade delivery and requires alternative strategies and LV venting

What do cross-clamp time and bypass time represent clinically?

Cross-clamp time = duration of myocardial ischemia while the heart is arrested
Bypass time = total duration on CPB, reflecting systemic exposure to non-physiologic circulation
Prolonged cross-clamp time (>2–3 hours) increases risk of myocardial dysfunction, especially with poor baseline function
Longer bypass time is associated with increased risk of renal injury, coagulopathy, and bleeding
These metrics often reflect both case complexity and intraoperative challenges

What is hypothermic circulatory arrest (HCA) and when is it used?

HCA involves complete cessation of blood flow to allow a bloodless surgical field
Typically used in complex aortic arch repairs
Patients are cooled to ~18°C to reduce metabolic demand and protect organs
Duration is ideally limited to <30 minutes to minimize neurologic injury
Adjuncts include:
- Antegrade cerebral perfusion (ACP) – provides targeted brain perfusion
- Retrograde cerebral perfusion (RCP) – less effective for oxygen delivery

What makes redo congenital cardiac surgery high risk?

Re-entry risk depends on anatomical relationships:
- Aorta adherent to sternum (especially midline) poses high risk of catastrophic bleeding
- RVOT conduits or pressurized chambers near sternum increase injury risk
Loss of peripheral vascular access from prior procedures limits bailout options
Accumulated comorbidities (renal, hepatic dysfunction) increase perioperative risk
Diastolic dysfunction and ventricular impairment complicate weaning from bypass
Complexity of planned repair and institutional/surgeon experience significantly influence outcomes

What does “venting the ventricle” mean and why is it important?

Venting refers to decompression of the left ventricle using a cannula (often via right superior pulmonary vein)
Prevents LV distension, which can impair myocardial protection and lead to hemodynamic collapse
Particularly important in the presence of aortic insufficiency or inadequate forward flow
Failure to adequately vent can result in arrhythmias, poor recovery, and adverse outcomes

What materials are used in congenital surgery and how do they impact long-term care?

Common patch materials include bovine pericardium (durable, non-stretch), Dacron, Gore-Tex, and autologous pericardium
Conduits (e.g., homografts, Contegra, Hancock) are used to connect cardiac structures and often contain valves
Most materials do not grow with the patient and are prone to calcification over time
Surgical decisions must consider future transcatheter or surgical interventions
Limited availability of certain graft sizes (e.g., pulmonary homografts) impacts real-world decision-making

References:

1. Salis, S. et al. Cardiopulmonary bypass duration is an independent predictor of morbidity and mortality after cardiac surgery. J Cardiothorac Vasc Anesth. 2008;22(6):814-822. doi:10.1053/j.jvca.2008.08.004

2. Al-Sarraf, N. et al. Cross-clamp time is an independent predictor of mortality and morbidity in low- and...