Brugada phenocopy in a patient with pectus excavatum: systematic review of the ECG manifestations associated with pectus excavatum

Unsophisticated assessment of the cardiopulmonary function in patients with pectus excavatum using the six minute walk test

BACKGROUND

We explored whether the maximum predicted walking distance, assessed with six-minute walk test (6MWT) and reflecting submaximal functional exercise capacity, is decreased among patients with pectus excavatum (PEX).

METHODS

This study comprised a retrospective analysis of patients with PEX who underwent a 6MWT for the assessment of functional capacity. The maximum distance walked was recorded and compared to reference values established for different populations, including a young and healthy South American population.

RESULTS

We included 43 patients with PEX who underwent 6MWT. The mean age was 17.8 ± 6.7 years. The mean maximum distance walked was significantly lower than the predicted distance (600.8 ± 67.6 metres vs. 729.8 ± 67.5 metres, p < 0.0001). Using the Enright reference equation including an older reference population, the mean negative difference was higher (PEX patients walked 190.4 ± 78.4 metres less than predicted, p < 0.0001). We also applied the Li et al. reference equation accounting for sex among other variables, detecting a decreased walked distance compared to the gender-adjusted predicted distance (PEX patients walked a mean 222.4 ± 87.4 metres less than predicted, p < 0.0001). Using the Ulrich et al. equation, PEX patients walked a mean 114.2 ± 85.1 metres less than predicted (p < 0.0001). Although of uncertain clinical relevance, there was a significant decrease in the mean oxygen saturation after exercise (baseline 97.4 ± 1.2%, vs. final 96.4 ± 2.1%, p = 0.006).

CONCLUSIONS

In this study, we identified a significant reduction in the maximum walked distance among patients with PEX compared to the predicted distance, thus potentially emerging as an unsophisticated means to evaluate and quantify functional exercise capacity.

Clinical Management of Brugada Syndrome: Commentary From the Experts

Although there is consensus on the management of patients with Brugada Syndrome with high risk for sudden cardiac arrest, asymptomatic or intermediate-risk patients present clinical management challenges. This document explores the management opinions of experts throughout the world for patients with Brugada Syndrome who do not fit guideline recommendations. Four real-world clinical scenarios were presented with commentary from small expert groups for each case. All authors voted on case-specific questions to evaluate the level of consensus among the entire group in nuanced diagnostic and management decisions relevant to each case. Points of agreement, points of controversy, and gaps in knowledge are highlighted.

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.

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 .

Presyncope in a Patient Status Post Pectus Excavatum Repair

Pectus excavatum (PEX) is an anterior chest wall deformity with sternal depression relative to the costal cartilages. We describe a patient status post remote PEX repair who presented with presyncope attributed to bifascicular block, partial right ventricular outflow tract (RVOT) obstruction, and right coronary artery (RCA) ischemia. Key Clinical Message: The clinician should be cognizant of the hemodynamic impact and electrocardiographic changes in a symptomatic patient status post pectus excavatum repair.

Determinants of electrocardiographic abnormalities in patients with pectus excavatum

BACKGROUND

Electrocardiographic abnormalities such as cardiac axis deviation, conduction abnormalities and ST-segment, and T &P wave abnormalities have been reported in patients with pectus excavatum. The precise determinants of these electrocardiographic abnormalities have however not been systematically evaluated. We therefore carried out this exploratory study to assess the electrocardiographic abnormalities and their determinants in children and young adults with pectus excavatum.

METHODS

Patients aged between 6 and 22 years with unrepaired pectus excavatum were eligible for enrollment in this preliminary hypothesis generating study, if they were seen at University of Chicago Medical Center between Jan 1, 2017 to Nov 30, 2020, and underwent an electrocardiogram during comprehensive evaluation for pectus excavatum. Pertinent data was collected from the medical charts. Unadjusted and adjusted logistic regression models were used to determine the effect of variables including age, BMI, inspiratory Haller's index, gender, right ventricular geometric distortion and FEV1/FVC (% predicted) on odds of electrocardiographic abnormalities (primary outcome variable). P-values of <0.05 were considered significant.

RESULTS

The study group (16.6 ± 2.9 years, 80% symptomatic) consisted of 28 patients [Caucasian, male (n = 24, 86% each)]. A high proportion (86%) of these patients had geometric distortion of the right ventricle on noninvasive imaging and these patients had a higher Haller's index (4.4 ± 0.95 vs 3.3 ± 0.2, p = 0.03). Approximately 60% of the patients had an abnormal electrocardiogram. Unadjusted and adjusted logistic regression models were utilized to study the determinants of these electrocardiographic abnormalities. Haller's index, BMI, age, gender, geometric distortion of the right ventricle and lung function parameters [FEV1/FEV (% predicted)] were not associated with increased odds of electrocardiographic abnormalities.

CONCLUSIONS

Electrocardiographic abnormalities, particularly deviation of cardiac axis, are common in patients with pectus excavatum. In this exploratory hypothesis generating study, Haller's index and geometric distortion of the right ventricle were not associated with these abnormalities. However, systematic multicentric efforts are needed to better define electrocardiographic abnormalities in patients with pectus excavatum and elucidate their precise determinants.

Pectus excavatum requiring temporary pacemaker implantation before Nuss procedure: a case report

Pectus excavatum is the most common chest wall deformity, and some patients also have it combined with cardiac arrhythmias. It is a rare occurrence for there to be a severe conduction block that requires a temporary pacemaker implantation before the surgical correction. Here we reported a case of pectus excavatum with a second-degree atrial-ventricular (AV) block (Mobitz II) who had temporary pacemaker implantation before the Nuss procedure. The young patient had a chest wall deformity for 6 years and it got worse with age. The Haller index was 4.21, and we evaluated that he should receive the Nuss procedure. An AV block was found during the preoperative electrocardiogram examination; furthermore, Holter monitor proved that he had first-degree AV block and a second-degree AV block (Mobitz II). After consultation with the anesthesiologist and cardiologist, we suggested that a temporary pacemaker placement should be performed under local anesthesia before the minimally invasive operation and removed as soon as the patient revived from general anesthesia. A postoperative Holter monitor was implemented, and the conduction defect disappeared shortly after the operation. However, the Holter monitor showed that the conduction defect was still existed during the follow-up period, which indicated that severe conduction defects should be originated from the conduction system itself, rather than the compression to the heart. The temporary pacemaker was essential to ensure the conducting of the operation went smoothly.

Brugada Phenocopy Type 1 Secondary to Synthetic Cannabinoids

Brugada phenocopies (BrP) are clinical entities that have EKG tracings similar to the congenital Brugada syndrome (BrS) but without ventricular tachyarrhythmias or sudden cardiac death. BrP is caused by various factors such as metabolic disturbances (electrolyte imbalance), drugs, mechanical compression of the mediastinum, and inflammatory conditions such as myocarditis or pericarditis. We present a very rare case of a young patient who had a Brugada phenocopy Type 1 suspected to be secondary to synthetic cannabinoids.

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.

Brugada Syndrome or Phenocopy? Diagnostic Challenge in Patients with Pectus Excavatum

Brugada syndrome is an autosomal dominant heart disease caused by dysfunctions in the ionic channels, whose carriers present a classic electrocardiographic pattern and predisposition to malignant ventricular arrhythmias. The electrocardiogram alterations may be dynamic, spontaneous, or induced by sodium channel blocking drugs (ajmaline, procainamide, etc.). However, electrocardiographic findings that diagnose Brugada syndrome may occur even in the absence of congenital dysfunction of ionic channels, characterizing “Brugada phenocopy”, therefore the exclusion of secondary causes is fundamental for the correct diagnosis of channelopathy.

Síndrome de Brugada ou Fenocópia? Desafio Diagnóstico em Paciente com Pectus Excavatum

A Síndrome de Brugada é uma doença cardíaca autossômica dominante causada por disfunções nos canais iônicos, cujos portadores apresentam padrão eletrocardiográfico clássico e predisposição a arritmias ventriculares malignas. As alterações do eletrocardiograma podem ser dinâmicas, espontâneas ou induzidas por drogas bloqueadoras dos canais de sódio (ajmalina, procainamida, etc.). No entanto, os achados eletrocardiográficos que diagnosticam Síndrome de Brugada podem ocorrer mesmo na ausência de disfunção congênita dos canais iônicos, caracterizando “fenocópia de Brugada”, portanto a exclusão de causas secundárias é fundamental para o correto diagnóstico da canalopatia.

The relationship between J waves and contact of lung cancer with the heart

BACKGROUND

J waves result mainly from an increased density of transient outward current (Ito ). Mechanical stretch to the heart activates multiple signal transduction pathways, in which Ito may be involved. The purpose of this study was to test the hypothesis that mechanical contact of lung cancer with the heart may manifest J waves.

METHODS

We reviewed 12-lead electrocardiograms to examine whether J waves were associated with contact of lung cancer with the heart. J waves were defied as an elevation of ≥0.1 mV at the junction between QRS complex and ST segment with either notching or slurring morphology. The locational interaction between lung cancer and the heart was determined by computed tomography image.

RESULTS

A total of 264 patients (176 men; mean 68.5 ± 10.7 years) with lung cancer were evaluated. The prevalence of J waves was 25.4% in the total population. J waves were present in 40 of 44 (90.9%) patients with the contact. In contrast, J waves were present in 25 of 220 (11.4%) patients without the contact. The sensitivity and specificity of the contact for J waves were 90.9% and 88.6%, respectively. The odds ratio of the contact with the heart to the presence of J waves was 78 (95% confidence interval 25.7-236.4). The appearance of J waves that coincided with the development of lung cancer was observed in 12 patients.

CONCLUSION

The presence of J waves was associated with the contact of lung cancer with the heart.

Pectus excavatum: Right ventricular compromise with orthostatic syndrome and Brugada phenocopy

Pectus excavatum (PEXT) consists of an overgrowth of the chondral region with posterior displacement of the inferior part of the sternum, resulting in a concave chest deformity. Characteristic clinical and imaging findings may occur, depending on the compression that right cardiac chambers suffer, when squeezed between the sternum and the column vertebrae.

Brugada syndrome, Brugada phenocopy or none?

Brugada syndrome is a form of inherited arrhythmia syndrome characterized by a distinct ST-segment elevation in the right precordial leads. Brugada phenocopies are clinical entities that present with an electrocardiographic pattern identical to Brugada syndrome and may obey to various clinical conditions. We present a case of a suicidal attempt using a high dose of propafenone causing a Brugada-type electrocardiographic pattern. Is this a Brugada syndrome case, a Brugada phenocopy or something else?

Brugada phenocopy in a patient with acute pulmonary embolism presenting with recurrent syncope

Brugada phenocopy (BrP) refers to a group of clinical conditions that have etiologies distinct from Brugada syndrome (BrS). Although both demonstrate features of ST-segment elevation in the right precordial leads on the electrocardiogram (ECG), one must be distinguished from the other as their treatment options are different. We report a male patient who presented with recurrent syncope with a Brugada and a S1Q3T3 pattern on the ECG. Acute pulmonary embolism (APE) complicated by BrS was suspected. Twenty-four hours Holter monitoring did not demonstrate any evidence of ventricular arrhythmias. Computed tomography pulmonary angiogram confirmed the presence of an APE. He was treated with low molecular weight heparin and a repeat ECG taken the next day showed resolution of the Brugada and S1Q3T3 patterns. This case report illustrates that APE and BrS can present with similar clinical and electrocardiographic features of recurrent syncope and Brugada pattern, respectively.

Methods for Improving the Diagnosis of a Brugada ECG Pattern

Brugada syndrome (BrS) is an inherited channelopathy that predisposes individuals to malignant arrhythmias and can lead to sudden cardiac death. The condition is characterized by two electrocardiography (ECG) patterns: the type-1 or "coved" ECG and the type-2 or "saddleback" ECG. Although the type-1 Brugada ECG pattern is diagnostic for the condition, the type-2 Brugada ECG pattern requires differential diagnosis from conditions that produce a similar morphology. In this article, we present a case that is suspicious but not diagnostic for BrS and discuss the application of ECG methodologies for increasing or decreasing suspicion for a diagnosis of BrS.

Massive pulmonary embolism mimicking electrocardiographic pattern of Brugada syndrome

Brugada syndrome is an inherited heart disease without structural abnormalities that is thought to arise as a result of accelerated inactivation of Na channels and predominance of transient outward K current to generate a voltage gradient in the right ventricular layers. Brugada syndrome occurs in patients with structurally normal heart and predisposes patients to malignant ventricular arrhythmias. Acute pulmonary embolism has been associated with a variety of electrocardiograms,and rarely, it may mimic electrocardiographic pattern of Brugada syndrome and this condition was defined as Brugada phenocopy.

Cardiopulmonary arrest during the Nuss procedure: case report and review

Case

The Nuss procedure is an established and widely approved minimally invasive technique for the correction of pectus excavatum. However, patients undergoing the procedure are at increased risk of cardiac arrest. It has not been established whether cardiopulmonary resuscitation is possible in patients who have received the Nuss procedure. We present here the case of a 14-year-old boy with pectus excavatum who underwent minimally invasive pectus repair but later had a fatal cardiac event before pectus bar removal.

Outcome

Bystander cardiopulmonary resuscitation was carried out immediately but resuscitation failed.

Conclusion

In patients who have undergone the Nuss procedure for pectus excavatum, it is important to manage perioperative events such as arrhythmia, develop measures for managing emergency situations in patients' areas of residence, and carry out continuing research and development of medical supply materials that can be used to manufacture Nuss bars.

Differential diagnosis of rSr' pattern in leads V1 -V2. Comprehensive review and proposed algorithm

One of the more frequent dilemmas in ECG interpretation is the differential diagnosis of an rSr' pattern in leads V1 -V2 . We often face this finding in asymptomatic and otherwise healthy individuals and the causes may vary from benign nonpathological variants to severe or life-threatening heart diseases, such as Brugada syndrome or arrhythmogenic right ventricular dysplasia. In other cases, a normal variant of rSr' pattern can be misinterpreted as pathological after the occurrence of certain clinical events such as cardiac arrest or syncope of unknown cause. In this review we analyze in detail all the possible conditions, both benign and pathological that may explain the presence of this electrocardiographic pattern. We also propose a simple electrocardiographic algorithm for differential diagnosis.

Brugada phenocopy: A new electrocardiogram phenomenon

Brugada phenocopies (BrP) are clinical entities that are etiologically distinct from true congenital Brugada syndrome. BrP are characterized by type 1 or type 2 Brugada electrocardiogram (ECG) patterns in precordial leads V1-V3. However, BrP are elicited by various underlying clinical conditions such as myocardial ischemia, pulmonary embolism, electrolyte abnormalities, or poor ECG filters. Upon resolution of the inciting underlying pathological condition, the BrP ECG subsequently normalizes. To date, reports have documented BrP in the context of singular clinical events. More recently, recurrent BrP has been demonstrated in the context of recurrent hypokalemia. This demonstrates clinical reproducibility, thereby advancing the concept of this new ECG phenomenon. The key to further understanding the pathophysiological mechanisms behind BrP requires experimental model validation in which these phenomena are reproduced under strictly controlled environmental conditions. The development of these validation models will help us determine whether BrP are transient alterations of sodium channels that are not reproducible with a sodium channel provocative test or alternatively, a malfunction of other ion channels. In this editorial, we discuss the conceptual emergence of BrP as a new ECG phenomenon, review the progress made to date and identify opportunities for further investigation. In addition, we also encourage investigators that are currently reporting on these cases to use the term BrP in order to facilitate literature searches and to help establish this emerging concept.

Brugada phenocopy clinical reproducibility demonstrated by recurrent hypokalemia

Brugada phenocopies (BrP) are clinical entities that are etiologically distinct from true congenital Brugada syndrome (BrS). BrP are characterized by type 1 or type 2 Brugada electrocardiogram (ECG) patterns in precordial leads V1 -V3 ; however, BrP are elicited by various underlying clinical conditions such as electrolyte disturbances, myocardial ischemia, or poor ECG filters. In this report, we describe the first case of clinically reproducible BrP which is important to the conceptual evolution of BrP.