Pectus excavatum (PE) is the most common congenital chest wall deformity, with a prevalence exceeding 1% in certain populations. Its presence may be associated with connective tissue disorders and/or congenital heart defects, which may also require surgical correction. Additionally, PE can develop during adolescence following cardiac surgery performed in early childhood. Although PE may be present at birth, it typically progresses with age, becoming symptomatic in adolescence when it reaches severe stages. 

A thorough evaluation is essential to determine surgical indications, particularly to rule out other potential causes of symptoms. Conventional studies (ECG, chest X-ray, blood tests) are necessary, along with pulmonary function tests and imaging studies, such as CT or MRI. 

Surgical indications are based on clinical findings and imaging studies. One of the most commonly used and valuable parameters is the Haller index (transverse diameter divided by anteroposterior diameter). Normal values range from 2.5 to 2.7, with correction recommended for indices above 3.25. 

In many cases, the aesthetic impact of PE alone may justify surgery. In others, the indication is established by the physiological impact of PE compression on cardiopulmonary function, including reduced maximal oxygen uptake, impaired diastolic function, decreased cardiac output, and pulmonary restriction. These effects worsen with age as chest wall compliance decreases, leading to exertional dyspnea, exercise intolerance, palpitations (especially due to supraventricular tachycardias), chest pain, and other symptoms. 

Correcting the defect can be expected to significantly improve clinical outcomes, as thoracic decompression enhances respiratory parameters (normalization of FEV1 and improved maximal oxygen uptake), increases right ventricular stroke volume, and consequently improves cardiac output. 

The Nuss technique is the preferred method for repairing PE in pediatric populations. This minimally invasive procedure involves inserting curved bars (convex-shaped) along the ribs, passing behind the sternum to elevate the depressed area. First described by D. Nuss in 1998, it preserves costal cartilages, unlike conventional techniques such as Ravitch. The procedure involves bilateral mid-axillary incisions (approximately 3-4 cm) at the subpectoral plane, with bars introduced through intercostal spaces in the defect area, guided by videothoracoscopy. The bars are maneuvered through the chest wall, anterior mediastinum, and then extracted subpectorally at the contralateral incision. A retractor elevates the sternum, increasing anterior mediastinal space to minimize the risk of injuring mediastinal structures. 

This article discusses recommendations from the Mayo Clinic group regarding the management strategy for patients undergoing PE repair after congenital heart defect (CHD) surgery in infancy or requiring concomitant correction of CHD and PE. 

An specific action plan was stablished for each scenario: 

1. Repair of Pectus Excavatum in Patients Previously Operated for Congenital Heart Defects: A hybrid approach is recommended, involving a resternotomy followed by the Nuss technique. This minimizes the risk of cardiac damage during dissection to insert the bars by allowing constant visualization of their trajectory. A protective membrane should be placed over the anterior heart surface to prevent direct contact with the bars. The sternum is conventionally approximated using cerclages attached to the retractor, which facilitates elevation for bar passage. Direct visualization eliminates the need for videothoracoscopy. Bars should remain in place for 3-4 years; this duration may be extended in cases of connective tissue disorders due to the risk of recurrence. 
2. Concomitant Repair of Pectus Excavatum and Congenital Heart Defects: Whenever feasible, both corrections should be performed in a single surgical procedure. The significant impact of PE on cardiac function, particularly in the immediate postoperative period when myocardial edema, hyperdynamic states, or ventricular dysfunction may occur, underscores this recommendation. Several groups report positive clinical and aesthetic outcomes with medium-term follow-ups, highlighting the safety of this approach. However, in cases of hemodynamic instability or significant postoperative bleeding following cardiac surgery, PE repair may be delayed by 24-72 hours. 

Regarding technique, initial sternal approximation with wires is performed, followed by thoracic wall elevation using a retractor to create space for bar placement. 

COMMENTARY: 

The overall incidence of major complications in PE repair using the Nuss technique is low. As noted, the hemodynamic benefits are significant, leading to substantial improvements in patients’ quality of life. The Nuss technique is particularly advantageous in pediatric populations, as it preserves costal cartilage, reduces bleeding risk compared to traditional techniques, and avoids cartilage devascularization, which minimizes recurrence risks. 

Whenever possible, both procedures should be performed concomitantly. However, in cases of significant bleeding or hemodynamic instability following cardiac surgery, PE repair may be considered within 24-72 hours after ensuring clinical stability. At La Paz Hospital, our approach involves addressing both pathologies concomitantly, deferring PE correction by 24-48 hours post-CHD repair. Current evidence supports good outcomes, although caution is advised when drawing conclusions due to limited case numbers. As with all rare pathologies, patients should ideally be treated in specialized centers with close collaboration between congenital cardiac and thoracic surgery teams. 

REFERENCE: 

Stephens EH, Dearani JA, Jaroszewski DE. Pectus Excavatum in Cardiac Surgery Patients. Ann Thorac Surg. 2023 May;115(5):1312-1321. doi: 10.1016/j.athoracsur.2023.01.040.