Coronary artery anomalies on preoperative cardiac CT in children with tetralogy of Fallot or Fallot type of double outlet right ventricle: comparison with surgical findings

Contemporary multimodality non-invasive cardiac imaging protocols for tetralogy of Fallot

Tetralogy of Fallot is the most prevalent cyanotic congenital heart disease, requiring lifelong multimodality non-invasive cardiac imaging, such as echocardiography, cardiothoracic computed tomography, and cardiac magnetic resonance imaging. As imaging techniques continuously evolve and are gradually integrated into clinical practice, there is a critical need to update multimodality imaging protocols. Over the last two decades, cardiothoracic computed tomography imaging techniques have advanced remarkably, significantly enhancing its role in evaluating patients with tetralogy of Fallot. In this review, we describe contemporary multimodality non-invasive cardiac imaging protocols for tetralogy of Fallot, emphasizing the expanding role of cardiothoracic computed tomography. Additionally, we present standardized reporting forms designed to facilitate the clinical adoption of these protocols.

Detection of Coronary Artery and Aortic Arch Anomalies in Patients with Tetralogy of Fallot Using CT Angiography

Background: Tetralogy of Fallot (TOF) is the most common form of cyanotic congenital heart disease (CHD). Furthermore, the prevalence of anomalous origin of a coronary artery is higher in patients with TOF than in the general population (6% vs. ≤1%). Preoperative assessment of cardiovascular anatomy using computed tomography (CT) angiography enables the adaptation of the surgical approach to avoid potentially overlooked anomalies. Our purpose was to determine the prevalence of coronary artery and aortic arch anomalies in a cohort of TOF patients. Methods: In this retrospective analysis, data were collected from CT reports (2015–2021) of 105 TOF patients. All images were acquired using a 64-slice multi-detector CT (MDCT) scanner. Results: The median age of the patients was 38.7 months, with a male-to-female ratio of 1.39. The overall prevalence of coronary artery anomalies (CAAs) was 7.61% (8 of 105 cases). The anomalous origin and course of coronary arteries across the right ventricular outflow tract (RVOT; prepulmonic course) were defined in 5.71% of cases (six patients). In four of these, the left anterior descending artery (LAD) originated from the right coronary artery (RCA), while in two cases, the RCA arose from the LAD. In the remaining two patients, the coronary arteries followed an interarterial course. The most frequent anomalous aortic arch pattern in the overall TOF population was the right aortic arch (RAA) with mirror image branching, seen in 20% of patients (21 cases). The most frequent anomaly of the supra-aortic trunks was bovine configuration, found in 17.14% (18 cases). Conclusions: The prevalence of CAAs and aortic arch anomalies detected by CT angiography was in line with the data reported in anatomical specimens. Therefore, this technique represents a powerful tool for the evaluation of congenital cardiovascular anomalies.

CT of cardiac and extracardiac vascular anomalies: embryological implications

Background

Congenital heart disease (CHD) is the most common neonatal anomaly. Extracardiac findings are commonly associated with CHD. It is mandatory to evaluate extracardiac structures for potential associated abnormalities that might impact the surgical planning for these patients. The purpose of this study was to determine the extracardiac abnormalities that could associate cardiac anomalies and to give insights into their embryological aberrations.

Results

Thirty-two pediatric patients (22 males and 10 females) underwent CT angiography to assess CHD. Diagnosis of the CHD and associated extracardiac findings were recorded and tabulated by organ system and type of CHD. Retrospective ECG-gated low-peak kilovoltage (80Kvp) technique was used on 128MDCT GE machine. Patients were diagnosed according to their CHD into four groups: chamber anomalies 90%, septal anomalies 81.3%, conotruncal anomalies 59.4%, and valvular anomalies 59.4%. Extracardiac findings were found in 28 patients (87.5%) with a total of 76 findings. Vascular findings were the most prevalent as 50 vascular findings were observed in 28 patients. Aortic anomalies were the commonest vascular anomalies. Fourteen thoracic findings were observed in 12 patients; of them lung consolidation patches were the most common and 12 abdominal findings were found in seven patients, most of findings were related to situs abnormalities.

Conclusion

Extracardiac abnormalities especially vascular anomalies are commonly associating CHD. Along with genetic basis, aberrations in dynamics of blood flow could represent possible causes of this association.

Double Outlet Right Ventricle: In-Depth Anatomic Review Using Three-Dimensional Cardiac CT Data

Double outlet right ventricle (DORV) is a relatively common congenital heart disease in which both great arteries are connected completely or predominantly to the morphologic RV. Unlike other congenital heart diseases, DORV demonstrates various anatomic and hemodynamic subtypes, mimicking ventricular septal defect, tetralogy of Fallot, transposition of the great arteries, and functional single ventricle. Because different surgical strategies are applied to different subtypes of DORV with ventricular septal defects, a detailed assessment of intracardiac anatomy should be performed preoperatively. Due to high spatial and contrast resolutions, cardiac CT can provide an accurate characterization of various intracardiac morphologic features of DORV. In this pictorial essay, major anatomic factors affecting surgical decision-making in DORV with ventricular septal defects were comprehensively reviewed using three-dimensional cardiac CT data. In addition, the surgical procedures available for these patients and major postoperative complications are described.

Imaging Findings of Coronary Artery Fistula in Children: A Pictorial Review

Coronary artery fistula, defined as an abnormal communication between the coronary arteries and a cardiac chamber (most commonly) or a thoracic great vessel, may result in hemodynamically significant problems due to vascular shunting in children. Echocardiography, cardiac catheterization, cardiac MRI, and cardiac CT may be used to evaluate coronary artery fistula in children. Recently, CT has played a pivotal role for the accurate diagnosis of coronary artery fistula in children. Surgical or interventional treatment is performed for hemodynamically significant coronary artery fistulas. In this pictorial review, the detailed imaging findings of coronary artery fistula in children are described.

Anomalous Origin of the Coronary Artery from the Pulmonary Artery in Children and Adults: A Pictorial Review of Cardiac Imaging Findings

Anomalous origin of the coronary artery from the pulmonary artery is a rare and potentially fatal congenital heart defect. Up to 90% of infants with an anomaly involving the left coronary artery die within the first year of life if left untreated. Patients who survive beyond infancy are at risk of sudden cardiac death. Cardiac CT and MRI are increasingly being used for the accurate diagnosis of this anomaly for prompt surgical restoration of the dual coronary artery system. Moreover, life-long imaging surveillance after surgery is necessary for these patients. In this pictorial review, multimodal cardiac imaging findings of this rare and potentially fatal coronary artery anomaly are comprehensively discussed, and representative images are provided to facilitate the understanding of this anomaly.

Pediatric Cardiothoracic CT Guideline Provided by the Asian Society of Cardiovascular Imaging Congenital Heart Disease Study Group: Part 2. Contemporary Clinical Applications

The use of pediatric cardiothoracic CT for congenital heart disease (CHD) was traditionally limited to the morphologic evaluation of the extracardiac thoracic vessels, lungs, and airways. Currently, the applications of CT have increased, owing to technological advancements in hardware and software as well as several dose-reduction measures. In the previously published part 1 of the guideline by the Asian Society of Cardiovascular Imaging Congenital Heart Disease Study Group, we reviewed the prerequisite technical knowledge for clinical applications in a user-friendly and vendor-specific manner. Herein, we present the second part of our guideline on contemporary clinical applications of pediatric cardiothoracic CT for CHD based on the consensus of experts from the Asian Society of Cardiovascular Imaging CHD Study Group. This guideline describes up-to-date clinical applications effectively in a systematic fashion.

Anomalies of coronary arteries in tetralogy of Fallot: Evaluation on multidetector CT angiography using dual-source scanner

OBJECTIVES

The present study sought to determine the prevalence and evaluate the patterns of various anomalies of coronary arteries in patients with tetralogy of Fallot (TOF) on multidetector CT angiography using a dual-source CT scanner.

METHODS

We retrospectively reviewed CT angiographies of 955 pediatric patients, diagnosed with TOF between 1st January 2015 and 31st December 2019 and having an optimal evaluation of coronary arteries, with respect to the origin, course, and termination of the coronary arteries and associated cardiovascular anomalies.

RESULTS

Anomalies of coronary arteries were observed in 8.27% (79/955) patients with TOF. Origin of accessory/proper left anterior descending (LAD) artery from right coronary artery (RCA) or right coronary sinus was the most common anomalous pattern, seen in 3.14% (30/955) patients, followed by the presence of hypertrophied conal artery seen in 2.62% (25/955) patients. The anomalous coronary artery was crossing the right ventricular outflow tract (RVOT) in all cases where the LAD artery was arising from RCA or right coronary sinus or where RCA was arising from the LAD artery. Coronary arterial anomalies were seen in a significantly higher proportion of patients with an atrial septal defect compared to those without (7/25 [28%] vs. 72/930 [7.74%]; p = .0003).

CONCLUSION

The prevalence of anomalies of coronary arteries increases significantly in the presence of TOF as compared to the general population. Majority of these anomalous coronary arteries course anterior to the RVOT which can potentially pose technical difficulties with a risk of adverse surgical outcomes and increased morbidity and mortality, rendering their diagnosis crucial before surgery.

Coronary artery anomalies in tetralogy of Fallot patients evaluated by multi slice computed tomography; myocardial bridge is not a rare finding

Based on coronary angiography and interoperative inspection, anomalous origin of coronary artery crossing the right ventricular outflow tract (RVOT) is common in tetralogy of Fallot (TOF) patients. However, other coronary anomalies may be underestimated due to the overlying myocardium, epicardial fat, or adhesions due to previous palliative surgery. Currently, coronary artery visibility dramatically improved by multislice computed tomography (MSCT). We performed this study to assess the coronary arteries anatomy in TOF patients using MSCT.All TOF patients underwent MSCT examination at our centre from 2013 till 2019 were included. Assessment of the coronary arteries' origin and course were performed. Presence of myocardial bridge were assessed, and indexed RV mass was calculated.318 TOF patients were included, median age 2 years (range 1 month-46 years), 175 males (55%). The abnormal coronary artery origin and course were detected in 20 patients (6%); coronary artery crossed RVOT in 13 patients (65%), 5 patients (25%) had a retro-aortic course and 2 patient (10%) had inter-arterial course. Myocardial bridges of left anterior descending artery or/and right coronary artery were reported in 100 patients (36%), no myocardial bridge of left circumflex was reported. RV mass was 29.0 ± 21.1 g/m2. There was no correlation between RV mass and presence of myocardial bridges.MSCT is a useful imaging modality for detection of coronary arteries anomalies in TOF patients. Coronary artery crossing RVOT is not the only abnormal course and myocardial bridging is not a rare finding. Further studies are needed to demonstrate the clinical significance of these observations.

Narrative review of assessing the surgical options for double outlet right ventricle

The individualized surgical approach in individuals with both arterial trunks arising from the morphologically right ventricle is dictated by the extreme morphological variability encountered in this setting, with each patient being unique. An individualized surgical approach has been designed to take account of the morphological variations, identifying the anatomy with the preoperative three-dimensional CT scan reconstruction. The key features have been considered the distance between tricuspid and pulmonary valves, the size and location of the interventricular communication, and the relationship between the outflow tracts. The surgical approach is tailored, whenever feasible, to create a connection between left ventricle and aorta, but primarily to achieve biventricular repair. Account has been taken of all available surgical options already reported in the literature, identifying the most suitable to provide the best outcomes for each unique morphology. To date, meaningful comparison between different reported surgical series has been difficult because of the marked variation of individual intracardiac morphology, and the lack of reports of specific surgical approaches for well-categorized groups of patients. Our approach, being tailored to the individual cardiac morphology, can be offered to any patient with this ventriculo-arterial connection. Given the difficulties of diagnosis, and the multiple therapeutic indications, very close collaboration between cardiologists and surgeons is indispensable for further progress in the understanding and management of this complex congenital cardiac lesion.

Noninvasive imaging of congenital cardiovascular defects

Advances in the treatment have drastically increased the survival rate of congenital heart disease (CHD) patients. Therefore, the prevalence of these patients is growing. Imaging plays a crucial role in the diagnosis and management of this population as a key component of patient care at all stages, especially in those patients who survived into adulthood. Over the last decades, noninvasive imaging techniques, such as cardiac magnetic resonance (CMR) and cardiac computed tomography (CCT), progressively increased their clinical relevance, reaching stronger levels of accuracy and indications in the clinical surveillance of CHD. The current review highlights the main technical aspects and clinical applications of CMR and CCT in the setting of congenital cardiovascular abnormalities, aiming to address a state-of-the-art guidance to every physician and cardiac imager not routinely involved in the field.

Changes in Right Ventricular Volume, Volume Load, and Function Measured with Cardiac Computed Tomography over the Entire Time Course of Tetralogy of Fallot

Objective

To characterize the changes in right ventricular (RV) volume, volume load, and function measured with cardiac computed tomography (CT) over the entire time course of tetralogy of Fallot (TOF).

Materials and Methods

In 374 patients with TOF, the ventricular volume, ventricular function, and RV volume load were measured with cardiac CT preoperatively (stage 1), after palliative operation (stage 2), after total surgical repair (stage 3), or after pulmonary valve replacement (PVR) (stage 4). The CT-measured variables were compared among the four stages. After total surgical repair, the postoperative duration (POD) and the CT-measured variables were correlated with each other. In addition, the demographic and CT-measured variables in the early postoperative groups were compared with those in the late postoperative and the preoperative group.

Results

Significantly different CT-based measures were found between stages 1 and 3 (indexed RV end-diastolic volume [EDV], 63.6 ± 15.2 mL/m² vs. 147.0 ± 38.5 mL/m² and indexed stroke volume (SV) difference, 7.7 ± 10.3 mL/m² vs. 32.2 ± 16.4 mL/m²; p < 0.001), and between stages 2 and 3 (indexed RV EDV, 72.4 ± 19.7 mL/m² vs. 147.0 ± 38.5 mL/m² and indexed SV difference, 5.7 ± 13.1 mL/m² vs. 32.2 ± 16.4 mL/m²; p < 0.001). After PVR, the effect of RV volume load (i.e., indexed SV difference) was reduced from 32.2 mL/m² to 1.7 mL/m². Positive (0.2 to 0.8) or negative (−0.2 to −0.4) correlations were found among the CT-based measures except between the RV ejection fraction (EF) and the RV volume load parameters. With increasing POD, an early rapid increase was followed by a slow increase and a plateau in the indexed ventricular volumes and the RV volume load parameters. Compared with the preoperative data, larger ventricular volumes and lower EFs were observed in the early postoperative period.

Conclusion

Cardiac CT can be used to characterize RV volume, volume load, and function over the entire time course of TOF.