Effects of Pectus Excavatum Repair on Right and Left Ventricular Strain

The relationship between mitral valve prolapse and thoracic skeletal abnormalities in clinical practice: a systematic review

BACKGROUND

Literature data suggest high inter-study variability in mitral valve prolapse (MVP) prevalence among individuals with thoracic skeletal abnormalities (TSA). This systematic review aimed at estimating the overall prevalence of MVP in individuals with the most common TSA, including not only the oldest studies (before the year 2000) but also the most recent ones (after the year 2000).

METHODS

PubMed and EMBASE databases were systematically reviewed in November 2023. Studies assessing the relationship between MVP and TSA and estimating the MVP prevalence in pectus excavatum (PE), pectus carinatum (PC), scoliosis, straight back syndrome (SBS) and Marfan syndrome (MS) were included. There was no limitation on time periods.

RESULTS

Twenty-five studies with a total of 2800 patients (27.9 ± 13.9 years, 48.2% females) were analyzed. The highest prevalence of MVP was observed among MS patients (47.3%), while the lowest was detected in PC individuals (23%). Prevalence of MVP was similar among PE (30.8%), scoliosis (26.3%) and SBS (25.5%) patients. When dividing the studies on the basis of temporal period, the average MVP prevalence was approximately two-fold higher in all studies conducted before the year 2000 in comparison with the most recent ones, regardless of TSA type. This discrepancy might be primarily ascribed to relevant differences in the echocardiographic criteria employed for MVP diagnosis before (less specific) and after (more specific) the year 2000, respectively.

CONCLUSIONS

The estimated MVP prevalence in TSA individuals is significantly higher than that observed in the general population. Individuals with TSA should be screened for MVP presence on transthoracic echocardiography.

Does a high Haller index influence outcomes in pectus excavatum repair?

OBJECTIVE

Severity for pectus excavatum includes Haller index (HI) > 3.25. An extremely high HI (≥8) may influence surgical approach and complications. This study reviews outcomes of patients with high HI after repair.

METHODS

A single institution retrospective analysis was performed on adult patients with HI ≥ 8 undergoing pectus excavatum repairs. For outcomes, a propensity score-matched control group with a HI ≤ 4 was utilized.

RESULTS

In total, 64 cases (mean age, 33.5 ± 10.9 years; HI, 13.1 ± 5.0; 56% women) were included. A minimally invasive repair was successful in 84%. A hybrid procedure was performed in the remaining either to repair fractures of the ribs (8 patients) and sternum (5 patients) or when osteotomy and/or cartilage resection was required (10 patients). In comparison with the matched cohort (HI ≤ 4), patients with high HI had longer operative times (171 vs 133 minutes; P < .001), more frequently required hybrid procedures (16% vs 2%; P = .005), experienced higher incidences of rib (22% vs 3%; P = .001) and sternal fractures (12% vs 0%; P = .003), and had increased repair with 3 bars (50% vs 19%; P < .001). There were no significant differences between the groups for length of hospital stay or postoperative 30-day complications.

CONCLUSIONS

Patients with an extremely high HI can be challenging cases with greater risks of fracture and need for osteotomy/cartilage resection. Despite this, minimally invasive repair techniques can be utilized in most cases without increased complications when performed by an experienced surgeon.

Evolution of Pain Control for Adult Pectus Excavatum Repair

BACKGROUND

Pain control after minimally invasive repair of pectus excavatum (MIRPE) can be challenging, especially in adult patients undergoing surgical repair. This study reviewed different analgesic modalities used over ≥10 years after pectus repair.

METHODS

A retrospective analysis was performed of adult patients (≥18 years) who underwent uncomplicated primary MIRPE at a single institution from October 2010 to December 2021. Patients were classified by analgesic modality used: epidural, elastomeric continuous infusion subcutaneous catheters (SC-Caths), and intercostal nerve cryoablation. Comparisons among the 3 groups were performed.

RESULTS

In total, 729 patients were included (mean age, 30.9 ±10.3 years; 67% male; mean Haller index, 4.9 ±3.0). Patients in the cryoablation group required significantly lower doses of morphine equivalents (P < .001) and had overall the shortest hospital stay (mean, 1.9 ±1.5 days; P < .001) with <17% staying >2 days (vs epidural at 94% and SC-Cath at 48%; P < .001). The cryoablation group had a lower incidence of ileus and constipation (P < .001) but a higher incidence of pleural effusion requiring thoracentesis (P = .024). Mean pain scores among groups were minor (<3), and differences were insignificant.

CONCLUSIONS

The use of cryoablation in conjunction with enhanced recovery pathways provided significant benefit to our patients undergoing MIRPE compared with previous analgesic modalities. These benefits included a decrease in length of hospital stay, a reduction of in-hospital opioid use, and a lower incidence of opioid-related complications associated with constipation and ileus. Further studies to assess additional potential benefits with long-term follow-up after discharge are warranted.

Body measurement changes in adults with pectus excavatum after the Nuss procedure: a study of 272 patients

BACKGROUND

Pectus excavatum (PE) is the most common congenital abnormality of the chest wall. Most patients with PE have slim bodies. Some studies have been conducted on the physical growth of children and adolescents who underwent the Nuss procedure. This study aimed to evaluate body measurement changes in adult patients with PE after the Nuss procedure.

METHODS

A total of 272 adult PE patients, who underwent the Nuss procedure and pectus bars removal from August 2014 to December 2020, were evaluated retrospectively. Body measurement [body height (BH), body weight (BW), and body mass index (BMI)] of the patients were collected before Nuss repair and after bar removal. We used the interquartile range (IQR) to identify and exclude outliers. Associations between changes in body measurement and clinical and radiological features were evaluated.

RESULTS

The BH, BW and BMI showed significantly increased after pectus bar removal, compared to pre-Nuss procedure parameters (BH 173.8 ± 5.9 cm vs. 173.9 ± 5.9 cm, P < 0.001; BW 60.3 ± 8.1 kg vs. 61.1 ± 8.8 kg, P = 0.005; BMI 19.9 ± 2.2 kg/m2 vs. 20.1 ± 2.4 kg/m2, P = 0.02). The same result were observed in the male subgroup, the HI ≥ 4 group and the male subgroup within the HI ≥ 4 group.

CONCLUSIONS

The BH, BW and BMI were significantly increased after completing surgical correction of PE using the Nuss procedure, particularly in young males and patients with more pronounced deformities.

The electrocardiographic manifestations of pectus excavatum before and after surgical correction

BACKGROUND

Pectus excavatum (PEx) can cause cardiopulmonary limitations due to cardiac compression and displacement. There is limited data on electrocardiogram (ECG) alterations before and after PEx surgical repair, and ECG findings suggesting cardiopulmonary limitations have not been reported. The aim of this study is to explore ECG manifestations of PEx before and after surgery including associations with exercise capacity.

METHODS

A retrospective review of PEx patients who underwent primary repair was performed. ECGs before and after surgical correction were evaluated and the associations between preoperative ECG abnormalities and cardiopulmonary function were investigated.

RESULTS

In total, 310 patients were included (mean age 35.1 ± 11.6 years). Preoperative ECG findings included a predominant negative P wave morphology in V1, and this abnormal pattern significantly decreased from 86.9% to 57.4% (p < 0.001) postoperatively. The presence of abnormal P wave amplitude in lead II (>2.5 mm) significantly decreased from 7.1% to 1.6% postoperatively (p < 0.001). Right bundle branch block (RBBB) (9.4% versus 3.9%, p < 0.001), rsr' patterns (40.6% versus 12.9%, p < 0.001), and T wave inversion in leads V1-V3 (62.3% vs 37.7%, p < 0.001) were observed less frequently after surgery. Preoperative presence of RBBB (OR = 4.8; 95%CI 1.1-21.6) and T wave inversion in leads V1-3 (OR = 2.3; 95%CI 1.3-4.2) were associated with abnormal results in cardiopulmonary exercise testings.

CONCLUSION

Electrocardiographic abnormalities in PEx are frequent and can revert to normal following surgery. Preoperative RBBB and T wave inversion in leads V1-3 suggested a reduction in exercise capacity, serving as a marker for the need for further cardiovascular evaluation of these patients.

Combined Ravitch and Nuss procedure for patients with severe pectus excavatum: technique and initial results

The Nuss procedure for pectus excavatum (PE) is both less invasive and very simple compared to the Ravitch procedure. However, it may be difficult to perform the Nuss procedure in cases of severe PE. Therefore, we developed a Combined Ravitch and Nuss (CRN) procedure and examined its effectiveness in patients with severe PE. Nine patients with severe PE underwent the CRN procedure. Data on patient characteristics and perioperative results were collected retrospectively. The median Haller index (HI) was 15.4 (range, 6.3-29.3). No significant intraoperative adverse events were noted. Postoperatively, marked improvements in HI were seen in all cases (3.29, range, 2.72-4.96). Two surgical site infections on the shallow layer and one wound seroma occurred. No recurrences were observed during the observation period. Our novel CRN procedure is useful for achieving adequate and sustainable sternal elevation with less invasiveness for patients with severe PE.

Description of a new clinical syndrome: thoracic constriction without evidence of the typical funnel-shaped depression-the "invisible" pectus excavatum

Pectus excavatum (PE) is a congenital malformation with a funnel-shaped depression of the sternum that can lead to cardiac symptoms. However, there are patients with thoracic constriction (defined as elevated Haller-Index > 3.25 determined by cardiac magnetic resonance imaging (CMR)) without visible evidence of PE, leading to similar complaints. Between January 2004 till June 2020, patients who underwent CMR for further evaluation of the heart, due to cardiac symptoms were enrolled and compared to controls. Biventricular global strain analysis was assessed using feature tracking (CMR-FT). ECG and/or Holter recordings were performed to detect rhythm events. Cardiac symptoms were evaluated in detail using a questionnaire. Finally, 88 patients (male 35, female 53) with elevated Haller-Index (3.9 ± 0.8) were included and compared to CMR data from 25 individuals with confirmed PE and 25 healthy controls (HC). Mean age at time of CMR was 35 ± 16 years. The most common symptoms at presentation were palpitations (41%), followed by dyspnea (24%) and atypical chest pain (14%). Three patients (3%) had atrial fibrillation or atrial flutter. Concomitant phenomena were pericardial effusion in 39% and mitral valve prolapse (MVP) in 27% of the study cohort. While there were no differences in left ventricular function or volumes, right ventricular function (RVEF) was significantly lower in patients with internal PE compared to HC (RVEF (%) 50 ± 5 vs 59 ± 4, p < 0.01). Strain analysis revealed only discrete changes in RV strain, implying a purely mechanical problem in the absence of structural changes. RV dimensions were negatively correlated with the size of thoracic indices (r = 0.41), reflecting the extent of thoracic constriction. MVP was more prevalent in patients with greater thoracic indices (r = 0.24). The described cohort, referred to as internal PE because of the absence of external changes, showed similar CMR morphologic findings as patients with real PE (especially altered dimensions of the right heart and a lower RVEF). In addition, there was a high incidence of rhythm disturbances, such as extrasystoles or arrhythmias. In one-third of the study cohort additional abnormalities such as pericardial effusion or MVP were present, with MVP being found more frequently in patients with larger thoracic indices, suggesting a possible common pathogenesis.Trial registration: ISRCTN registry, ISRCTN15355937, retrospectively registered 03.06.2022, https://www.isrctn.com/ISRCTN15355937?q=15355937&filters=&sort=&offset=1&totalResults=1&page=1&pageSize=10 .

What Is the Appropriate Timing for Bar Removal After the Nuss Repair for Pectus Excavatum?

INTRODUCTION

The Nuss procedure for pectus excavatum requires that the sternal elevation be maintained by indwelling metal bars that are traditionally removed approximately 3 y after the repair.

METHODS

A retrospective cohort study was conducted of all patients who underwent primary Nuss repair from 2007 to 2018 in two institutions and had a follow-up of at least 24 mo. Pectus bars had been left in place beyond 3 y in patients concerned over possible recurrence after bar removal. Structured interviews were held to assess pain, chest tightness, or other discomfort, and any adverse events related to pectus bars. Results were compared between patients in whom pectus bars were removed after 3 y (standard group) and those in whom bars were left in place longer (extended bar duration group).

RESULTS

Two hundred and thirty-one patients (91% males, mean age 23.9 ± 8.3, mean Haller index 4.9 ± 2.3) were included. Bar duration was 30.6 ± 6.6 mo in the standard group (51 patients) versus 69.1 ± 26.3 mo in the extended group (180 patients). Some discomfort was reported by 81.6% in the standard group versus 62.9% in the extended group (P = 0.033), and discomfort occurring at least monthly or more often was only reported by 30% in the standard versus 30.3% in the extended group (P = 1.000). Quality of life improved in 92.6% of the standard group versus 94.7% of the extended group (P = 1.000). No significant adverse events were reported in either group.

CONCLUSIONS

Our data suggest that an extended bar duration after the Nuss repair may not cause any adverse event nor negatively affect quality of life.

The influence of pectus excavatum on cardiac kinetics and function in otherwise healthy individuals: A systematic review

BACKGROUND

A number of anterior chest wall deformities, most notably pectus excavatum (PE), may have a detrimental effect on cardiac motion and function. Interpretation of transthoracic echocardiography (TTE) and speckle-tracking echocardiography (STE) results may be hampered by the possible influence of PE on cardiac kinetics.

METHODS

A comprehensive search of all articles assessing cardiac function in PE individuals was carried out. Inclusion criteria were: 1) individuals aged >10 years; 2) studies providing objective assessment of chest deformity (Haller index). Studies that measured myocardial strain parameters in PE patients were also included.

RESULTS

The search (EMBASE and Medline) yielded a total of 392 studies, 36 (9.2%) of which removed as duplicates; a further 339 did not meet inclusion criteria. The full-texts of 17 studies were then analyzed. All studies concordantly reported impaired right ventricular volumes and function. With respect to left ventricle (LV), TTE studies uniformly demonstrated a significant impairment in conventional echoDoppler indices in PE individuals, whereas STE studies provided conflicting results. Importantly, LV functional alterations promptly reverted upon surgical correction of chest defect. In subjects with PE of mild-to-moderate severity, we observed that degree of anterior chest wall deformity, as noninvasively assessed by modified Haller index (MHI), was strongly associated with myocardial strain magnitude, in heterogenous cohorts of otherwise healthy PE individuals.

CONCLUSIONS

Clinicians should be aware that in PE individuals, TTE and STE results may not always be indicative of intrinsic myocardial dysfunction, but may be, at least in part, influenced by artifactual and/or external chest shape determinants.

Pectus Excavatum in Cardiac Surgery Patients

BACKGROUND

Pectus excavatum frequently accompanies congenital heart disease and connective tissue diseases requiring cardiac surgery. Sometimes the indication is cardiac repair, with the pectus being incidentally noticed; other times, the pectus subsequently develops or becomes more significant after cardiac surgery. This review arms cardiac and congenital surgeons with background about the physiologic impact of pectus, indications for repair and repair strategies, and outcomes for cardiac surgery patients requiring pectus repair.

METHODS

A comprehensive literature review was performed using keywords related to pectus excavatum, pectus repair, and cardiac/congenital heart surgery within the PubMed database.

RESULTS

The risks of complications related to pectus repair, including in the setting of cardiac surgery or after cardiac surgery, are low in experienced hands, and patients demonstrate cardiopulmonary benefits and symptom relief. Concomitant pectus and cardiac surgery should be considered if it is performed in conjunction with those experienced in pectus repair, particularly given the increased cardiopulmonary impact of pectus after bypass. In the setting of potential bleeding or hemodynamic instability, delayed sternal closure is recommended. For those with anticipated pectus repair after cardiac surgery, the pericardium should be reconstructed for cardiac protection. For those undergoing pectus repair after cardiac surgery without a membrane placed, a "hybrid" approach is safe and effective.

CONCLUSIONS

Patients undergoing cardiac surgery noted to have pectus should be considered for possible concomitant or staged pectus repair. For those who will undergo a staged procedure, a barrier membrane should be placed before chest closure.

The influence of chest wall conformation on myocardial strain parameters in a cohort of mitral valve prolapse patients with and without mitral annular disjunction

PURPOSE

To evaluate the possible influence of chest wall conformation on myocardial strain parameters in a cohort of mitral valve prolapse (MVP) patients with and without mitral annular disjunction (MAD).

METHODS

All consecutive middle-aged patients with MVP referred to our Outpatient Cardiology Clinic for performing two-dimensional (2D) transthoracic echocardiography (TTE) as part of work up for primary cardiovascular prevention between March 2018 and May 2022, were included into the study. All patients underwent clinic visit, physical examination, modified Haller index (MHI) assessment (the ratio of chest transverse diameter over the distance between sternum and spine) and conventional 2D-TTE implemented with speckle tracking analysis of left ventricular (LV) global longitudinal strain (GLS) and global circumferential strain (GCS). Independent predictors of MAD presence on 2D-TTE were assessed.

RESULTS

A total of 93 MVP patients (54.2 ± 16.4 yrs, 50.5% females) were prospectively analyzed. On 2D-TTE, 34.4% of MVP patients had MAD (7.3 ± 2.0 mm), whereas 65.6% did not. Compared to patients without MAD, those with MAD had: 1) significantly shorter antero-posterior (A-P) thoracic diameter (13.5 ± 1.2 vs 14.8 ± 1.3 cm, p < 0.001); 2) significantly smaller cardiac chambers dimensions; 3) significantly increased prevalence of classic MVP (84.3 vs 44.3%, p < 0.001); 4) significantly impaired LV-GLS (-17.2 ± 1.4 vs -19.4 ± 3.0%, p < 0.001) and LV-GCS (-16.3 ± 4.1 vs -20.4 ± 4.9, p < 0.001), despite similar LV ejection fraction (63.7 ± 4.2 vs 63.0 ± 3.9%, p = 0.42). A-P thoracic diameter (OR 0.25, 95%CI 0.10-0.82), classic MVP (OR 3.90, 95%CI 1.32-11.5) and mitral annular end-systolic A-P diameter (OR 2.76, 95%CI 1.54-4.92) were the main independent predictors of MAD. An A-P thoracic diameter ≤ 13.5 cm had 59% sensitivity and 84% specificity for predicting MAD presence (AUC = 0.81). In addition, MAD distance was strongly influenced by A-P thoracic diameter (r = - 0.96) and MHI (r = 0.87), but not by L-L thoracic diameter (r = 0.23). Finally, a strong inverse correlation between MHI and both LV-GLS and LV-GCS was demonstrated in MAD patients (r = - 0.94 and - 0.92, respectively), but not in those without (r = - 0.51 and - 0.50, respectively).

CONCLUSIONS

A narrow A-P thoracic diameter is strongly associated with MAD presence and is a major determinant of the impairment in myocardial strain parameters in MAD patients, in both longitudinal and circumferential directions.

Usefulness of strain cardiac magnetic resonance for the exposure of mild left ventricular systolic abnormalities in pectus excavatum

BACKGROUND

Systolic dysfunction in pectus excavatum (PEX) is usually very subtle and mainly focused on the right ventricle (RV), leading to normal or unremarkable cardiac imaging findings unless involving exercise stress.

OBJECTIVES

We evaluated systolic function in PEX using longitudinal strain cardiac magnetic resonance (CMR), a validated parameter for the assessment of the systolic deformation of subendocardial fibers.

METHODS

This prospective registry comprised consecutive patients with PEX who were referred to CMR to define treatment strategies or to establish surgical candidacy. We also included a control group of 15 healthy volunteers without chest wall abnormalities. Using dedicated software, we evaluated the endocardial global longitudinal strain (GLS) of both ventricles and the endocardial global circumferential strain (GCS) of the left ventricle (LV).

RESULTS

A total of 50 patients with PEX comprised the study population, with a mean age of 19.9 ± 8.0 years. The right ventricular ejection fraction (RVEF) of patients with PEX was significantly lower compared to the control group both at end-expiration (59.5 ± 6.8 vs. 64.7 ± 4.7%, p = 0.008) and end-inspiration (56.7 ± 7.2%, vs. 62.7 ± 4.4, p = 0.004); as well as the pulmonary stroke distance (12.6 ± 2.5, vs. 15.0 ± 2.0 cm, p = 0.001). The LV volumetric analysis revealed no differences between PEX and the control group (p > 0.05 for all) regardless of the respiratory cycle, with a mean expiratory LV ejection fraction (LVEF) of 61.4 ± 6.0%. In contrast, the GLS of the LV was significantly lower in PEX compared to controls (-21.2 ± 3.2 vs. -23.7 ± 3.0%, p = 0.010), whereas GCS was similar either at expiration (-28.5 ± 4.0%, vs. -29.5 ± 2.8, p = 0.38) or inspiration (-29.3 ± 4.1%, vs.-28.9 ± 2.3, p = 0.73).

CONCLUSIONS

In this study, we demonstrated that longitudinal strain analysis might enable the detection of very subtle left ventricular systolic function abnormalities in patients with PEX, that are commonly overlooked using the conventional assessment.

LEVEL OF EVIDENCE

II.

Molecular Approaches and Echocardiographic Deformation Imaging in Detecting Myocardial Fibrosis

The pathological remodeling of myocardial tissue is the main cause of heart diseases. Several processes are involved in the onset of heart failure, and the comprehension of the mechanisms underlying the pathological phenotype deserves special attention to find novel procedures to identify the site of injury and develop novel strategies, as well as molecular druggable pathways, to counteract the high degree of morbidity associated with it. Myocardial fibrosis (MF) is recognized as a critical trigger for disruption of heart functionality due to the excessive accumulation of extracellular matrix proteins, in response to an injury. Its diagnosis remains focalized on invasive techniques, such as endomyocardial biopsy (EMB), or may be noninvasively detected by cardiac magnetic resonance imaging (CMRI). The detection of MF by non-canonical markers remains a challenge in clinical practice. During the last two decades, two-dimensional (2D) speckle tracking echocardiography (STE) has emerged as a new non-invasive imaging modality, able to detect myocardial tissue abnormalities without specifying the causes of the underlying histopathological changes. In this review, we highlighted the clinical utility of 2D-STE deformation imaging for tissue characterization, and its main technical limitations and criticisms. Moreover, we focalized on the importance of coupling 2D-STE examination with the molecular approaches in the clinical decision-making processes, in particular when the 2D-STE does not reflect myocardial dysfunction directly. We also attempted to examine the roles of epigenetic markers of MF and hypothesized microRNA-based mechanisms aiming to understand how they match with the clinical utility of echocardiographic deformation imaging for tissue characterization and MF assessment.

Cardiopulmonary Outcomes After the Nuss Procedure in Pectus Excavatum

Background

Pectus excavatum is the most common chest wall deformity. There is still controversy about cardiopulmonary limitations of this disease and benefits of surgical repair. This study evaluates the impact of pectus excavatum on the cardiopulmonary function of adult patients before and after a modified minimally invasive repair.

Methods and Results

In this retrospective cohort study, an electronic database was used to identify consecutive adult (aged ≥18 years) patients who underwent cardiopulmonary exercise testing before and after primary pectus excavatum repair at Mayo Clinic Arizona from 2011 to 2020. In total, 392 patients underwent preoperative cardiopulmonary exercise testing; abnormal oxygen consumption results were present in 68% of patients. Among them, 130 patients (68% men, mean age, 32.4±10.0 years) had post‐repair evaluations. Post‐repair tests were performed immediately before bar removal with a mean time between repair and post‐repair testing of 3.4±0.7 years (range, 2.5–7.0). A significant improvement in cardiopulmonary outcomes (P<0.001 for all the comparisons) was seen in the post‐repair evaluations, including an increase in maximum, and predicted rate of oxygen consumption, oxygen pulse, oxygen consumption at anaerobic threshold, and maximal ventilation. In a subanalysis of 39 patients who also underwent intraoperative transesophageal echocardiography at repair and at bar removal, a significant increase in right ventricle stroke volume was found (P<0.001).

Conclusions

Consistent improvements in cardiopulmonary function were seen for pectus excavatum adult patients undergoing surgery. These results strongly support the existence of adverse cardiopulmonary consequences from this disease as well as the benefits of surgical repair.

Intraoperative cardiac function assessment by transesophageal echocardiography versus FloTrac/Vigileo™ system during pectus excavatum surgical repair

BACKGROUND

Pectus excavatum (PE), a congenital deformity of the chest wall, can lead to cardiac compression and related symptoms. PE surgical repair can improve cardiac function. Intraoperative transesophageal echocardiography (TEE) has been successfully employed to assess intraoperative hemodynamic variations in patients undergoing PE repair. FloTrac/Vigileo™ system (Edwards Life-sciences Irvine, CA) (FT/V) is a minimally invasive cardiac output monitoring system. This retrospective study aimed to assess hemodynamic changes in surgical repair of PE using FT/V and concordance with parameters measured by TEE.

RESULTS

N=19 patients submitted to PE repair via Ravitch or Nuss technique were enrolled. Intraoperative cardiac assessments simultaneously obtained via TEE and FT/V system were investigated. The agreement between TEE-derived cardiac output (CO-TEE) and FT/V system parameter (COAP) was evaluated. The relationship between COTEE and COAP was analyzed for all data using linear regression analysis. A significant correlation between COAP and COTEE values (R = 0.65, p < 0.001) was found. Bland-Altman analysis of COAP and COTEE showed a bias of 0.13 L/min and a limit of agreement of - 2.33 to 2.58 L/min, with a percentage error of 48%. Intraoperative measurements by TEE and FT/V both showed a significant increase in CO after surgical correction of PE (p < 0.005).

CONCLUSIONS

FT/V system compared to TEE in hemodynamic monitoring during PE surgery yielded clinically unacceptable results due to a high percentage error. After surgical correction of PE, CO, measured by TEE and FT/V, significantly improved.

Does chest wall conformation influence myocardial strain parameters in infants with pectus excavatum?

PURPOSE

To investigate the possible influence of chest wall conformation on myocardial strain parameters in a consecutive population of infants with pectus excavatum (PE), noninvasively assessed by modified Haller index (MHI).

METHODS

Sixteen consecutive PE infants (MHI >2.5) and 44 infants with normal chest shape (MHI ≤2.5) entered in this prospective case-control study. All infants underwent evaluation by neonatologist, transthoracic echocardiography implemented with two-dimensional speckle tracking echocardiography (2D-STE) analysis of both ventricles and MHI assessment (ratio of chest transverse diameter over the distance between sternum and spine), at two time points: within 3 days and at about 40 days of life.

RESULTS

At 2.1 ± 1 days of life, compared to controls (MHI = 2.01 ± 0.2), PE infants (MHI = 2.76 ± 0.2) were diagnosed with significantly smaller cardiac chambers dimensions. Biventricular contractile function and hemodynamics were similar in both groups of infants. Left ventricular (LV) global longitudinal strain (GLS) (-16.0 ± 2.8 vs. -21.7 ± 2.2%), LV-global circumferential strain (GCS) (-16.3 ± 2.7 vs. -24.0 ± 5.2%), LV-global radial strain (GRS) (24.2 ± 3.0 vs. 31.5 ± 6.3%), and right ventricular free wall longitudinal strain (RVFWLS) (-16.0 ± 3.2 vs. -22.3 ± 4.4%) were significantly reduced in PE infants versus controls (all p < 0.001). A strong inverse correlation between MHI and the following parameters: LV-GLS (r = -0.92), LV-GCS (r = -0.88), LV-GRS (r = -0.87), and RVFWLS (r = -0.88), was demonstrated in PE infants, but not in controls, in perinatal period (all p < 0.001). Analogous results were obtained at 36.8 ± 5.2 days after birth.

CONCLUSIONS

Abnormal chest anatomy progressively impairs myocardial strain parameters in PE infants. This impairment might reflect intraventricular dyssynchrony due to compressive phenomena rather than intrinsic myocardial dysfunction.

Gender differences in objective measures of adult patients presenting for pectus excavatum repair

BACKGROUND

Women have a reported incidence of pectus deformities 4-5 times less than men. Gender differences have not been well studied.

METHODS

A retrospective review was performed of adult patients (≥18 years) who underwent a pectus excavatum repair at Mayo Clinic in Arizona (January 1, 2010-December 31, 2019).

RESULTS

In total, 776 adults underwent pectus repair with 30% being women. Women presented older (mean age 35 vs 32 years, p=0.007) and more symptomatic. Despite this, women performed better on cardiopulmonary exercise testing (higher VO2 max and O2 pulse). Women had more severe deformities (Haller index 5.9 vs 4.3, p<0.001). However, in 609 patients undergoing attempted primary minimally invasive pectus repair, intraoperative fractures/osteotomies occurred equally between genders with the majority occurring in patients ≥30 years of age (11.5% in ≥30, 1.7% in <30, total 7%). Women were also less likely to require 3 bars for repair (12% vs 42%, p<0.001). Hospital length of stay and postoperative complication rates were not significantly different. Postoperatively women reported a greater daily intensity of pain, but only on the initial postoperative day used significantly more opioids than men. Cardiopulmonary exercise testing in 142 patients undergoing baseline and postoperative evaluation at bar removal showed equal and significant benefits in both genders.

CONCLUSIONS

Women presented for pectus excavatum repair older and with greater symptoms and severity. Despite this, women required fewer bars, with no significant differences in length of stay or complications. Cardiopulmonary benefits of repair were significant and equal for both genders.

The Severity of Pectus Excavatum Defect Is Associated With Impaired Cardiopulmonary Function

BACKGROUND

Repair of pectus excavatum has cosmetic benefits, but the physiologic impact remains controversial. The aim of this study was to characterize the relationship between the degree of pectus excavatum and cardiopulmonary dysfunction seen on cardiac magnetic resonance (CMR) imaging, cardiopulmonary exercise testing (CPET), and pulmonary function testing (PFT).

METHODS

A single-center analysis of CMR, CPET, and PFT was conducted. Regression models evaluated relationships between pectus indices and the clinical end points of cardiopulmonary function.

RESULTS

Data from 345 CMRs, 261 CPETs, and 281 PFTs were analyzed. Patients were a mean age of 15.2 ± 4 years, and 81% were aged <18 years. The right ventricular ejection fraction (RVEF) was <0.50 in 16% of patients, left ventricular ejection fraction (LVEF) was <0.55 in 22%, RVEF Z-score was < -2 in 32%, and the LVEF Z-score was < -2 in 18%. CPET revealed 33% of patients had reduced aerobic fitness. PFT results were abnormal in 23.1% of patients. Adjusted analyses revealed the Haller index had significant (P < .05) inverse associations with RVEF and LVEF.

CONCLUSIONS

The severity of pectus excavatum is associated with ventricular systolic dysfunction. Pectus excavatum impacts right and left ventricular systolic function and can also impact exercise tolerance. The Haller index and correction index may be the most useful predictors of impairment.

The strain and strain rate imaging paradox in echocardiography: overabundant literature in the last two decades but still uncertain clinical utility in an individual case

Almost two decades ago strain and strain rate imaging were proposed as a new, potentially more sensitive modality for quantifying both regional and global myocardial function. Until now, however, strain and strain rate imaging have been slow to be incorporated into everyday clinical practice. More recently, two dimensional strain has been claimed as of greater clinical utility, given that it is angle independent, with improved feasibility and reproducibility as compared to tissue Doppler strain. Nevertheless, speckle tracking strain is reliant on 2D image quality and frame rates. Three dimensional speckle tracking could eliminate the problem of through-plane motion inherent in 2D imaging, but 3D strain is currently limited by low frame rates. Another limitation of strain imaging is that the results are dependent on the ultrasound machine on which analyses are performed, with variability in measurements between different vendors. Despite the diagnostic and prognostic advantages of 2D strain, there is a lack of specific therapeutic interventions based on strain and a paucity of long-term large-scale randomized trial evidence on cardiovascular outcomes. After overabundant literature the same definition of normal cut-off values is controversial and not univocal. Further studies are needed, involving both manufacturers and medical professionals, on the additive contribution, possibly different case by case, of interfering and artifactual factors, aside from myocardial function per se. These artifactual determinants and motion artifacts components could be dominant in individual cases and should always be taken into account in the clinical decision making process in a single case.

Influence of chest conformation on myocardial strain parameters in healthy subjects with mitral valve prolapse

Chest shape might affect myocardial strain parameters. However, the relationship between myocardial strain parameters and chest conformation has not been previously investigated in subjects with mitral valve prolapse (MVP). Between April 2019 and May 2020, 60 healthy subjects (50.1 ± 8.6 year/old, 46.6% females) with MVP and mild-to-moderate mitral regurgitation, and 60 controls matched by age, sex, and cardiovascular risk factors were consecutively studied. Participants underwent modified Haller index (MHI) assessment (ratio of chest transverse diameter over the distance between sternum and spine), and transthoracic echocardiography implemented with 2D-speckle tracking analysis. MHI was significantly greater in MVP group than controls (2.6 ± 0.35 vs 2.1 ± 0.23, p < 0.0001). Left ventricular (LV) ejection fraction was similar in MVP and controls (63.5 ± 3.7% vs 64.3 ± 3.9%, p = 0.25). LV regional and global longitudinal (GLS), circumferential (GCS) and radial strain (GRS) parameters and LV peak twist were all significantly lower in MVP compared to controls (all p < 0.0001). MVP subjects with a tight chest (MHI > 2.5, n = 30), and those with MHI ≤ 2.5 (n = 30) were then separately analyzed. A significant impairment in myocardial strain parameters and LV peak twist was documented in MVP subjects with MHI > 2.5, but not in those with MHI ≤ 2.5. MHI showed a strong inverse correlation with LV-GLS (r = - 0.85), GCS (r = - 0.84), GRS (r = - 0.84) and LV peak twist (r = - 0.94). In MVP subjects, impairment of myocardial strain parameters is not due to intrinsic reduction of cardiac contractility function, but it appears to be related to the degree of chest deformity.

Diastolic and Systolic Cardiac Dysfunction in Pectus Excavatum: Relationship to Exercise and Malformation Severity

Purpose

To explore stress echocardiographic findings among patients with pectus excavatum (PEX) and their relationship with malformation severity.

Materials and Methods

A prospective registry involving consecutive patients with a diagnosis of isolated PEX referred to undergo chest CT and stress echocardiography to evaluate surgical candidacy and/or to define treatment strategies was developed. Malformation indexes were evaluated using chest CT.

Results

This study included 269 patients with PEX (19.7 years ± 7.8 [standard deviation]; 245 men) and 35 healthy volunteers (20.7 years ± 6.1; 21 men). Patients with PEX achieved a lower maximal workload (PEX group, 8.2 metabolic equivalents ± 1.7; control group, 11.8 metabolic equivalents ± 5.5; P < .0001). This study identified evidence of abnormal right ventricular diastolic function in 29% of patients with PEX and identified no evidence of this among those in the control group (P < .0001). Healthy controls showed a 37% increment in the tricuspid area during exercise, compared with 4% in patients with PEX (P = .002). Right ventricular systolic function was significantly lower in patients with PEX than in controls, both measured using tricuspid annulus plane systolic excursion (stress, 25.0 mm ± 5.5 vs 35.4 mm ± 3.7; P < .0001), and the tricuspid systolic wave was also smaller (stress, 16.9 cm/sec ± 4.5 vs 20.5 cm/sec ± 3.9; P < .0001). During stress, significant associations were detected between malformation indexes with right ventricular systolic and diastolic findings (P < .05 for all).

Conclusion

This study identified evidence of diverse adverse functional and morphologic cardiac manifestations in PEX, involving signs of abnormal diastolic and systolic right ventricular function and compression of the atrioventricular groove, which worsened during stress and were related to malformation severity.© RSNA, 2020: An earlier incorrect version of this article appeared online. This article was corrected on October 19, 2020.

Echocardiography Reveals Heart Abnormalities in Pediatric Pectus Carinatum

BACKGROUND

Symptoms including chest pain and palpitations are commonly described by pediatric patients with pectus deformity. Cardiac anomalies are thought to be less common in patients with pectus carinatum (PC) than those in patients with pectus excavatum; however, no literature supports this presumption. Echocardiogram (echo) assesses heart structure and function. We hypothesized that a screening echo would 1) determine the relationship between symptoms and echo findings and 2) define the incidence of cardiac defects in patients with PC.

MATERIALS AND METHODS

This is an institutional review board-approved retrospective review of all patients with PC who received an echo from 2015 to 2019 at a tertiary care children's hospital. Echo findings and patient-reported symptoms were collected from electronic health records. Descriptive statistics were used to assess correlation between findings.

RESULTS

We identified 155 patients with PC who received an echo with complete data available for analysis. Of these, 44 (28.4%) reported chest pain and 13 (8.4%) reported palpitations. Echo results showed that five patients (3.2%) had mitral valve prolapse and 11 (7.1%) had aortic root dilation. Patient-reported symptoms were not significantly associated with abnormal echo findings.

CONCLUSIONS

Chest pain and palpitations frequently occur in the PC population but may not be related to abnormal echo findings. We recommend screening echo in patients with PC regardless of symptoms.

Cardiac Transplantation and Consecutive Minimally Invasive Pectus Excavatum Repair

Pectus excavatum is a common chest wall deformity with inward deviation of sternum and accompanying ribs. The depression can cause symptomatic cardiac compression, although the cardiopulmonary impact remains controversial. We present 2 cases of cardiac transplantation followed by modified minimally invasive pectus excavatum repair due to the hemodynamic consequences of the pectus deformity.

Cardiopulmonary resuscitation in pediatric pectus excavatum patients-Where is the heart?

BACKGROUND

In children with pectus excavatum, the posteriorly depressed sternum compresses and displaces the heart. However, the currently recommended compression site and depth for cardiopulmonary resuscitation have not been studied in this population.

AIM

This retrospective study investigated the location of the center of ventricles with the largest cross-sectional area to determine the optimal site and depth for chest compressions in pediatric pectus excavatum patients.

METHODS

Chest computed tomography images of 94 pediatric pectus excavatum patients before and after correction surgery were compared with normal patients. The caudal displacement of the ventricles was calculated by dividing the length of sternum by the length from the suprasternal notch to the transverse level of the largest cross-sectional area of the ventricles. The proportional leftward deviation of the center of the ventricles from the midline versus transverse diameter of the thorax was calculated. The remaining internal thickness was calculated at the midline assuming the recommended compression depth of one-third of the anterior to posterior diameter.

RESULTS

Compared with the normal population (mean = 81% [SD = 10.3%]), pediatric pectus excavatum patients showed caudal displacement of ventricles before (98.2% [15.1%], 95% CI of mean difference; 13.7%-20.5%, P < .001) and after correction (100.4% [13.5%], 95% CI of mean difference; 16.2%-22.5%, P < .001). Compared with the normal population (6.9% [2.7%]), pediatric pectus excavatum patients showed leftward deviation of ventricles before (16.2% [5.5%], 95% CI of mean difference; 8.2%-10.4%, P < .001) and after correction (13.3% [4.8%], 95% CI of mean difference; 5.3%-7.3%, P < .001). The remaining internal thickness assuming the recommended chest compression was <10 mm in 54/94(57.4%) and 18/94 (19.1%) of pediatric pectus excavatum patients before and after correction, respectively.

CONCLUSIONS

Pediatric pectus excavatum patients showed significant caudal displacement and leftward deviation of the ventricles compared with the normal population despite correction surgery and the currently recommended compression site and depth might injure intrathoracic structures without effective cardiac compression during cardiopulmonary resuscitation.

Research progress in the effects of pectus excavatum on cardiac functions

Background

Pectus excavatum, the most common chest wall deformity in children, accounts for nearly 90% of congenital malformations of chest wall. Initially, both parents and doctors paid more attention to the influence of this deformity on patient appearance and psychology. Following deeper studies of pectus excavatum, researchers found that it also affected cardiac functions. The purpose of this review aims to present recent research progress in the effects of pectus excavatum on cardiac functions.

Data sources

Based on aspects of CT, ultrasound cardiography (UCG) and MRI, all the recent literatures on the influence of pectus excavatum on cardiac function were searched and reviewed.

Results

Moderate and severe pectus excavatum did have a negative effect on cardiac function. Cardiac rotation angle, cardiac compression index, right atrial and tricuspid annulus size, septal motion and myocardial strain are relatively effective indexes to evaluate cardiac function.

Conclusions

Pectus excavatum did have a negative effect on cardiac function; so surgeons should actively diagnose and treat such patients in clinical work. However, further research is needed on to explore the measures and indicators that can reflect the changes of cardiac function in patients objectively, accurately, effectively and timely.

Reduced Myocardial Strain Parameters in Subjects With Pectus Excavatum: Impaired Myocardial Function or Methodological Limitations Due to Chest Deformity?

Pectus excavatum (PE) may cause symptoms and alter cardiopulmonary function. Left ventricular (LV) and right ventricular (RV) function have been reported to be impaired in PE subjects. However, this issue has not been systematically investigated with respect to the degree of chest wall abnormality. We aimed to evaluate the influence of severity of chest shape abnormality on myocardial strain parameters in PE subjects. We studied 30 healthy subjects (55.8 ± 14.0 year/old, 18 males) with PE, assessed by the ratio of chest transverse diameter over the distance between sternum and spine (modified Haller index, MHI, >2.5), and 30 controls (MHI ≤2.5) matched by age, sex, and cardiovascular risk factors. Participants underwent 2-dimensional (2D) transthoracic echocardiography implemented with 2D-speckle tracking echocardiography. Right-heart and left-heart chamber dimensions, and stroke volume, were significantly reduced in PE subjects (all P< 0.0001). While LV ejection fraction, E/A, and E/e', did not significantly differ between the 2 groups, all LV and RV strain and strain rate parameters were severely reduced in subjects with PE (P < 0.0001). Importantly, in PE subjects, but not in controls, LV global longitudinal strain, LV global circumferential strain, LV global radial strain, and RV free wall systolic strain, were all linearly correlated to MHI (all P < 0.0001). In healthy subjects with PE, abnormal chest anatomy progressively impairs myocardial strain. However, this impairment is not due to subclinical myocardial dysfunction; it might reflect intraventricular dyssynchrony due to compressive phenomena, or technical limitations of strain methodology, due to chest wall abnormality.

Incremental value of three-dimensional transthoracic echocardiography over the two-dimensional modality in the assessment of right heart compression and dysfunction produced by pectus excavatum

The usefulness of two-dimensional transthoracic echocardiography (2DTTE) in the assessment of right heart compression and dysfunction produced by pectus excavatum chest wall deformity has been well described in the literature by several investigators. However, there is a paucity of reports describing incremental value of live/real time three-dimensional transthoracic echocardiography (3DTTE) over the two-dimensional technique in the evaluation of right heart function in these patients. We present a severe case of pectus excavatum chest wall deformity in a young male, in whom 3DTTE provided incremental value over standard 2DTTE in assessing compression of the right heart before surgery and marked improvement in right heart function parameters following surgical repair. In addition, an updated summary of salient features of this deformity, including 2D and 3DTTE findings as well as right heart echocardiographic parameters by both 2D and 3DTTE in normal/healthy subjects summarized from the literature have been provided in a tabular form for comparison.

Changes in resting pulmonary function testing over time after the Nuss procedure: A systematic review and meta-analysis

BACKGROUND

Pectus excavatum, the most common congenital chest wall deformity in pediatric patients, leads to pulmonary dysfunction. There is no consensus regarding the effectiveness of the Nuss procedure for recovering pulmonary function. In this meta- analysis, we focused on the changes that occur in pulmonary function after the Nuss procedure.

METHODS

We performed a literature search in the MEDLINE, Embase, Cochrane library and PubMed databases. The included studies were required to contain pulmonary function tests with results adjusted to predicted values both before and after the Nuss procedure. The key outcomes of interest in this analysis were pulmonary function measured as forced expiratory volume in 1s (FEV1) and forced vital capacity (FVC). Subgroup analyses were performed based on time since surgery and the mean ages of the patients when they underwent surgery by forest plots and meta-regressions.

RESULTS

Thirteen studies involving 465 participants were included in this review. The standard mean difference (SMD) observed in FEV1 and FVC after surgery were 0.17 (95% CI, 0.01-0.33, p=0.04) and -0.18 (95% CI, -0.41-0.06, p=0.14), respectively. The overall meta-regression SMD of FEV1 and FVC by time since surgery were 1.21 (95% CI, 1.04-1.41, p=0.020) and 1.38 (95% CI, 1.05-1.83, p=0.027), respectively. We found evidence of a temporal relationship between time at which pulmonary function tests were performed after surgery and predicted FEV1 and FVC values. The SMD of FEV1 (0.26, p=0.012) was slightly higher in group evaluated more than 2year after initial surgery.

CONCLUSIONS

Abnormal resting pulmonary functions tests performed prior to surgery showed an initial depression after surgery. The FEV1 of patients slightly increased at 2year post surgery compared with the baseline. Further studies with longer term follow-up are still needed to determine if pulmonary function could improve to normal after surgery.

LEVELS OF EVIDENCE

Level of evidence: 4 (based on lowest level of article analyzed in meta-analysis/systematic review).

The physiologic impact of pectus excavatum repair

The adverse physiologic effects of pectus excavatum and subsequent resolution following correction have been a subject of controversy. There are numerous accounts of patients reporting subjective improvement in exercise tolerance after surgery, but studies showing clear and consistent objective data to corroborate this phenomenon physiologically have been elusive. This is partially due to a lack of consistent study methodologies but even more so due to a mere paucity of data. As experts in the repair of pectus excavatum, it is not uncommon for pediatric surgeons to operate on adult patients. For this reason, this review evaluates the contemporary literature to provide an understanding of the physiologic impact of repairing pectus excavatum on pediatric and adult patients separately.

Nuss procedure in the adult population for correction of pectus excavatum

Minimally invasive repair of pectus excavatum has been successfully modified for use in adult patients. Many patients present in adulthood with progression of symptoms as the chest wall becomes less compliant with age. A thorough workup is completed including echocardiogram and chest CT to evaluate for anatomic abnormalities. Cardiopulmonary exercise testing is done to quantify the physiologic impact. Modifications of the original Nuss procedure required to allow for successful adult repair include the use of forced sternal elevation, the use of multiple bars, medial bar fixation, and interspace support to prevent bar rotation and migration. Occasionally, fractures may occur that require an open procedure and osteotomy or cartilage resection and hybrid approach incorporating the principals of intrathoracic support and osteotomy with bar stabilization.