Assessment of coronary artery aneurysms in paediatric patients with Kawasaki disease by multidetector row CT angiography: feasibility and comparison with 2D echocardiography

Giant coronary aneurysm in a toddler with Kawasaki disease: technical challenges in CT coronary angiography

Kawasaki disease is the most common vasculitis causing acquired coronary artery aneurysm (CAA) and affects mostly children. Computed tomography coronary angiography (CTCA) has unique diagnostic and prognostic values in cases of giant CAA. Here, we report technical challenges encountered when performed CTCA for a case of Kawasaki disease complicated with giant CAA. In particular, there was significant flow alteration caused by the giant CAA(s) causing suboptimal enhancement when the standard protocol was applied. We share our experience in optimizing the scan and propose the use of either manual bolus tracking or test bolus technique in similar scenarios, as well as multidisciplinary approach to optimize patient preparation.

Cardiac CT Angiography-Guided Management of Giant Coronary Artery Aneurysms in Atypical Kawasaki Disease: A Case Report and Review of Literature

Kawasaki disease (KD) is an auto-immune, acute febrile illness mostly affecting young children. It may develop into vasculitis characterized by coronary artery aneurysms (CAA) if not diagnosed and managed earlier. Timely diagnosis and appropriate treatment eventually avoid the risk of the development of CAA. We present the case of a 21-month-old female child with a history of persistent fever for nearly 10 days who further developed desquamations and presented for cardiac evaluation. Atypical KD with the development of giant CAAs was effectively diagnosed by cardiac computed tomographic angiography (CCTA) and was appropriately managed.

Emerging role of computed tomography coronary angiography in evaluation of children with Kawasaki disease

Coronary artery abnormalities are the most important complications in children with Kawasaki disease (KD). Two-dimensional transthoracic echocardiography currently is the standard of care for initial evaluation and follow-up of children with KD. However, it has inherent limitations with regard to evaluation of mid and distal coronary arteries and, left circumflex artery and the poor acoustic window in older children often makes evaluation difficult in this age group. Catheter angiography (CA) is invasive, has high radiation exposure and fails to demonstrate abnormalities beyond lumen. The limitations of echocardiography and CA necessitate the use of an imaging modality that overcomes these problems. In recent years advances in computed tomography technology have enabled explicit evaluation of coronary arteries along their entire course including major branches with optimal and acceptable radiation exposure in children. Computed tomography coronary angiography (CTCA) can be performed during acute as well as convalescent phases of KD. It is likely that CTCA may soon be considered the reference standard imaging modality for evaluation of coronary arteries in children with KD.

Distal coronary artery abnormalities in Kawasaki disease: experience on CT coronary angiography in 176 children

OBJECTIVE

Precise evaluation of coronary artery abnormalities (CAAs) in Kawasaki disease (KD) is essential. The aim of this study is to determine role of CT coronary angiography (CTCA) for detection of CAAs in distal segments of coronary arteries in patients with KD.

METHODS

CTCA findings of KD patients with distal coronary artery involvement were compared with those on transthoracic echocardiography (TTE) during the period 2013-21.

RESULTS

Among 176 patients with KD who underwent CTCA (128-Slice Dual Source scanner), 23 (13.06%) had distal CAAs (right coronary-15/23; left anterior descending-14/23; left circumflex-4/23 patients). CTCA identified 60 aneurysms-37 proximal (36 fusiform; 1 saccular) and 23 distal (17 fusiform; 6 saccular); 11 patients with proximal aneurysms had distal contiguous extension; 9 patients showed non-contiguous aneurysms in both proximal and distal segments; 4 patients showed distal segment aneurysms in absence of proximal involvement of same coronary artery; 4 patients had isolated distal CAAs. On TTE, only 40 aneurysms could be identified. Further, distal CAAs could not be identified on TTE. CTCA also identified complications (thrombosis, mural calcification and stenosis) that were missed on TTE.

CONCLUSIONS

CAAs can, at times, occur in distal segments in isolation and also in association with, or extension of, proximal CAAs. CTCA demonstrates CAAs in distal segments of coronary arteries, including branches, in a significant number of children with KD-these cannot be detected on TTE. CTCA may therefore be considered as a complimentary imaging modality in children with KD who have CAAs on TTE.

Cardiac Involvement in Children Affected by COVID-19: Clinical Features and Diagnosis

COVID-19 (Coronavirus disease 2019) in children is usually mild. However, multiple organ disorders associated with SARS-CoV-2 (severe acute respiratory syndrome-related coronavirus 2) have been detected with poor respiratory symptoms. Cardiac changes are noted in 17% to 75% of cases, which are associated with diagnostic difficulties in high-risk groups for the development of complications that are associated with myocardial damage by the SARS-CoV-2 virus. The objective of this review is to identify the most significant symptoms of cardiac involvement affected by COVID-19, which require in-depth examination. The authors analyzed publications from December 2019 to the October 2022, which were published in accessible local and international databases. According to the analysis data, the main sign of myocardial involvement was increasing as cardiomarkers in the patient's blood, in particular troponin I or troponin T. Many authors noted that the increased level of CRP (C-reactive protein) and NT-proBNP, which are accompanied by changes in the ECG (electrocardiogram) and EchoCG (echocardiography), as a rule, were nonspecific. However, the identified cardiac functional dysfunctions affected by SARS-CoV-2, required an cardiac MRI. The lack of timely diagnosis of myocardial involvements, especially in children at high risk for the development of complications associated with SARS-CoV-2 myocardial injury, can lead to death. The direct damage of the structural elements of myocardial blood vessels in patients with severe hypoxic changes resulted from respiratory failure caused by SARS-CoV-2 lung damage, with the development of severe acute diffuse alveolar damage and cell-mediated immune response and myocardial involvement affected by SARS-CoV-2 damage. In this article, the authors introduce a clinical case of a child who dead from inflammatory myocardities with COVID-19 in a background of congenital heart disease and T-cell immunodeficiency.

Multisystem Imaging Manifestations of Kawasaki Disease

Kawasaki disease (KD) is a common pediatric vasculitis syndrome involving medium- and small-sized arteries that is especially prevalent in early childhood (ie, age 6 months to 5 years). The diagnosis of KD is made on the basis of clinical features, such as fever, characteristic mucocutaneous changes, and nonsuppurative cervical lymphadenopathy. However, early diagnosis is often challenging because many children with KD present with atypical symptoms. The most serious complication of KD is coronary artery aneurysm caused by coronary arteritis. Prompt intravenous immunoglobulin therapy reduces the risk of cardiac morbidity. In addition, the systemic extension of KD-related vasculitis during the acute phase causes a variety of multisystem manifestations, including encephalopathy, stroke, retropharyngeal edema, pericarditis, myocarditis, KD shock syndrome, pulmonary lesions, intestinal pseudo-obstruction, gallbladder hydrops, arthritis, and myositis. These complications tend to be more common in affected children with atypical presentation. Radiologists can play an important role in the timely identification of diverse KD-associated morbidities and thus may contribute to the early diagnosis of atypical KD. Online supplemental material is available for this article. ^©RSNA, 2021.

Coronary Artery Aneurysm in Kawasaki Disease: Coronary CT Angiography through the Lens of Pathophysiology and Differential Diagnosis

Kawasaki disease (KD) is an inflammatory autoimmune vasculitis affecting the coronary arteries of very young patients, which can result in coronary artery aneurysms (CAAs) with lifelong manifestations. Accurate identification and assessment of CAAs in the acute phase and sequentially during the chronic phase of KD is fundamental to the treatment plan for these patients. The differential diagnosis of CAA includes atherosclerosis, other vasculitic processes, connective tissue disorders, fistulas, mycotic aneurysms, and procedural sequelae. Understanding of the initial pathophysiology and evolutionary arterial changes is important to interpretation of imaging findings. There are multiple applicable imaging modalities, each with its own strengths, limitations, and role at various stages of the disease process. Coronary CT angiography is useful for evaluation of CAAs as it provides assessment of the entire coronary tree, CAA size, structure, wall, and lumen characteristics and visualization of other cardiothoracic vasculature. Knowledge of the natural history of KD, the spectrum of other conditions that can cause CAA, and the strengths and limitations of cardiovascular imaging are all important factors in imaging decisions and interpretation. Keywords: Pediatrics, Coronary Arteries, Angiography, Cardiac © RSNA, 2021.

Multimodality cardiac evaluation in children and young adults with multisystem inflammation associated with COVID-19

Aims

Following the peak of the UK COVID-19 epidemic, a new multisystem inflammatory condition with significant cardiovascular effects emerged in young people. We utilized multimodality imaging to provide a detailed sequential description of the cardiac involvement.

Methods and Results

Twenty consecutive patients (mean age 10.6 ± 3.8 years) presenting to our institution underwent serial echocardiographic evaluation on admission (median day 5 of illness), the day coinciding with worst cardiac function (median day 7), and the day of discharge (median day 15). We performed cardiac computed tomography (CT) to assess coronary anatomy (median day 15) and cardiac magnetic resonance imaging (CMR) to assess dysfunction (median day 20). On admission, almost all patients displayed abnormal strain and tissue Doppler indices. Three-dimensional (3D) echocardiographic ejection fraction (EF) was <55% in half of the patients. Valvular regurgitation (75%) and small pericardial effusions (10%) were detected. Serial echocardiography demonstrated that the mean 3D EF deteriorated (54.7 ± 8.3% vs. 46.4 ± 8.6%, P = 0.017) before improving at discharge (P = 0.008). Left main coronary artery (LMCA) dimensions were significantly larger at discharge than at admission (Z score –0.11 ± 0.87 vs. 0.78 ± 1.23, P = 0.007). CT showed uniform coronary artery dilatation commonly affecting the LMCA (9/12). CMR detected abnormal strain in all patients with global dysfunction (EF <55%) in 35%, myocardial oedema in 50%, and subendocardial infarct in 5% (1/20) patients.

Conclusions

Pancarditis with cardiac dysfunction is common and associated with myocardial oedema. Patients require close monitoring due to coronary artery dilatation and the risk of thrombotic myocardial infarction.

Giant coronary artery aneurysm in infantile Kawasaki disease: When to use cardiac computed tomography angiography

Transthoracic echocardiography is the imaging modality of choice for the detection of coronary artery aneurysms (CAAs) in Kawasaki disease. However, cardiac computed tomography angiography is useful in the diagnosis of distal CAAs.

CT Coronary Angiography Studies After a Mean Follow-up of 3.8 Years in Children With Kawasaki Disease and Spontaneous Defervescence

Background: There is paucity of literature on follow-up of children with Kawasaki disease (KD) who have spontaneous defervescence during the acute stage and do not receive intravenous immunoglobulin. We report herein the role of computed tomography coronary angiography (CTCA) as an imaging modality in such situations. Methods: This prospective observational study was carried out during the period January 2016-June 2017. Children underwent CTCA on 128-slice Dual Source CT (DSCT) scanner (Somatom Definition Flash, Siemens; Germany), and 2D-echocardiography on the same day. Results: Mean age at time of diagnosis was 6.52 ± 3.13 years; range 2-14 years. Mean age at time of study was 11.03 ± 5.10 years; range 3.75-23.30 years. Mean interval between diagnosis of KD and time of present study was 3.84 ± 2.27 years. None of the patients showed any coronary artery abnormalities on either 2D-echocardiography or CTCA. While assessment of proximal segments of left main coronary artery, proximal right coronary artery, and left anterior descending artery was comparable on both 2D-echocardiography and CTCA, left circumflex artery, and distal right coronary artery could be clearly visualized only on CTCA. Conclusion: In our experience, patients with KD who have spontaneous defervescence during the acute stage and do not receive IVIg may not have significant long-term coronary sequelae. CTCA is a useful imaging modality for delineation of coronary artery in patients with KD on long term follow-up especially in older children with thick chest walls and poor acoustic windows.

Coronary artery assessment in Kawasaki disease with dual-source CT angiography to uncover vascular pathology

Background

Kawasaki disease (KD) is a vasculitis with formation of coronary artery aneurysms (CAAs) that can lead to myocardial ischemia. Echocardiography is the primary imaging modality for the coronary arteries despite limited visualization. Coronary angiography (CAG) is the gold standard yet invasive with high-radiation exposure. To date however, state-of-the-art CT scanners enable high-quality low-dose coronary computed tomographic angiography (cCTA) imaging. The aim of our study in KD is to report (i) the diagnostic yield of cCTA compared to echocardiography, and (ii) the radiation dose.

Methods and results

We collected data of KD patients who underwent cCTA. cCTA findings were compared with echocardiography results. In 70 KD patients (median age 15.1 years [0.5–59.5 years]; 78% male; 38% giant CAA), the cCTA identified 61 CAAs, of which 34 (56%, with a Z score > 3, in 22 patients) were not detected by echocardiography. In addition, the left circumflex (aneurysmatic in 6 patients) was always visible upon cCTA and not detected upon echocardiography. Calcifications, plaques, and/or thrombi were visualized by cCTA in 25 coronary arteries (15 patients). Calcifications were seen as early as 2.7 years after onset of disease. In 5 patients, the cCTA findings resulted in an immediate change of treatment. The median effective dose (ED) in millisievert differed significantly (p < 0.01) between third-generation dual-source and other CT scanners (1.5 [0.3–9.4] (n = 56) vs 3.8 [1.7–20.0] (n = 14)).

Conclusions

The diagnostic yield of third-generation dual-source cCTA combined with reduced radiation exposure makes cCTA a favorable diagnostic modality to complete the diagnosis and long-term treatment indications for KD.

Key Points

• cCTA is a favorable diagnostic modality to complete the diagnosis and long-term treatment indications for Kawasaki disease.

• Kawasaki disease patients with proven coronary artery involvement on echocardiography require additional imaging.

The Role of Computed Tomography Coronary Angiography in Kawasaki Disease: Comparison with Transthoracic Echocardiography in a 25-Case Retrospective Study

Although transthoracic echocardiography (TTE) is the first-line examination for the study of coronary lesions in Kawasaki disease, CT coronary angiography (CTCA) is increasingly used and showed good results. Our aim is to evaluate the contribution of CTCA in the detection of coronary lesions and to compare its results with those of TTE. Retrospective study that included 25 patients with Kawasaki disease enrolled in La Rabta University Hospital. The study was conducted over a 4-year period from January 2012 to May 2015. A TTE and a CTCA have been performed for all patients during KD first 3 months of evolution to investigate the coronary artery lesions. There were 23 lesions described on CTCA and not diagnosed with TTE: there were 16 aneurysms, 6 ectasia and 1 case of stenosis. The lesions concerned: LCX in eight cases, RCA in eight cases, LMCA in three cases, and LAD and PDA in two cases each. Differences of description between TTE and CTCA were identified in 14 cases. These discrepancies concerned the type of lesion in seven cases (50%), the size of the aneurysm in five cases (35%) and the shape of the aneurysm in two cases. The CTCA showed its superiority in detecting coronary lesions in our series especially fusiform ones and those interesting distal and posterior network. However, because of its radiating character and its availability, TTE should remain the fist-line examination.

Computed tomography in paediatric heart disease

Cardiovascular CT (CCT) is an important imaging modality in congenital and acquired paediatric heart disease. Technological advances have resulted in marked improvements in spatial and temporal resolution of CCT with a concomitant increase in speed of data acquisition and a decrease in radiation dose. This has elevated CCT from being sparingly used to an essential diagnostic tool in the daily multimodality imaging practice alongside echocardiography, cardiovascular MR and invasive angiography. The application of CCT in paediatric congenital and acquired heart disease can be both technically and diagnostically challenging. This review highlights important considerations for current state of the art CCT across the spectrum of heart disease encountered in children.

Coronary manifestations of Kawasaki Disease in computed tomography coronary angiography

Coronary arteritis in Kawasaki disease can lead to serious complications such myocardial infarction and sudden death. The identification of coronary manifestations with a method that is minimally invasive and of low radiation exposure is therefore important in paediatric patients with Kawasaki disease. Coronary CT angiography can be an attractive alternative to invasive coronary angiography. This paper describes imaging techniques for coronary CT angiography in pediatric patients and demonstrates the spectrum of cardiovascular manifestations in patients with Kawasaki disease.

Radiation dose management for pediatric cardiac computed tomography: a report from the Image Gently 'Have-A-Heart' campaign

Children with congenital or acquired heart disease can be exposed to relatively high lifetime cumulative doses of ionizing radiation from necessary medical imaging procedures including radiography, fluoroscopic procedures including diagnostic and interventional cardiac catheterizations, electrophysiology examinations, cardiac computed tomography (CT) studies, and nuclear cardiology examinations. Despite the clinical necessity of these imaging studies, the related ionizing radiation exposure could pose an increased lifetime attributable cancer risk. The Image Gently "Have-A-Heart" campaign is promoting the appropriate use of medical imaging studies in children with congenital or acquired heart disease while minimizing radiation exposure. The focus of this manuscript is to provide a comprehensive review of radiation dose management and CT performance in children with congenital or acquired heart disease.

Role of imaging studies in Kawasaki disease

Kawasaki disease is a medium vessel vasculitis which may be associated with coronary artery abnormalities. Recognition of these abnormalities depends upon various imaging modalities. While two-dimensional echocardiography remains the first line modality to identify coronary artery abnormalities, it is subject to several fallacies and is operator dependent. Computed tomography coronary angiography is rapidly emerging as a useful imaging modality for better characterization of dilatations, ectasia and aneurysms in the mid- and distal segments of coronary arteries. It provides precise details in terms of aneurysm size and morphology. In this review we here described the importance of computed tomography coronary angiography and have also given a brief description of magnetic resonance coronary angiography.

Computed tomography coronary angiography is the way forward for evaluation of children with Kawasaki disease

Kawasaki disease (KD) is an acute idiopathic vasculitis affecting infants and children. Coronary artery abnormalities and myocarditis are the major cardiovascular complications of KD. Coronary artery abnormalities develop in 15–25% of untreated KD. Two-dimensional transthoracic echocardiography has hitherto been considered the modality of choice for evaluation of children with KD. There are, however, several limitations inherent to echocardiography - including limited evaluation of distal vessels, left circumflex artery and poor acoustic window in growing children. Catheter angiography is the gold standard for evaluation of coronary artery abnormalities in older children and adults; however it also has inherent limitations - including complications related to its invasive nature, higher radiation exposure, and inability to evaluate intramural abnormalities. Thus serial invasive coronary angiography studies are not feasible in children. There have been major advances in computed tomography (CT) coronary imaging so that it is now possible to delineate the coronary artery anatomy with higher temporal resolution and motion-free images at all heart rates with acceptable radiation exposure. There is, however, a paucity of literature with regard to the use of this technique in children with KD. In this review, we discuss the application of computed tomography coronary angiography (CTCA) in children with KD with special reference to strategies aimed at reducing the effective radiation dose.

Computed Tomography Coronary Angiography for Evaluation of Children With Kawasaki Disease

OBJECTIVE

We sought to assess the feasibility of computed tomography coronary angiography (CTCA) on a 128-slice, dual source scanner in children with acute and convalescent phase Kawasaki disease (KD).

MATERIALS AND METHODS

A prospective study of 49 children with KD (12 at presentation and 37 in the convalescent phase) was conducted between November 2013 and April 2015. CTCA was performed with either prospective (n = 37) or retrospective (n = 12) electrocardiographic gating. A radiologist blinded to clinical profile and echocardiogram evaluated each scan.

RESULTS

Median age (36 boys and 13 girls) was 7 years. Median dose-length product value and median effective CT radiation dose was 32mGycm (interquartile range [IQR]: 21-74) and 0.54 miliSieverts (mSv) (IQR: 0.77-3.2) for all scans, and 27mGycm (IQR: 18.5-33.75) and 0.48mSv (IQR: 0.18-1.17) for prospectively triggered scans (n = 37). Fourteen subjects (30 coronary segments) showed abnormalities by CTCA including aneurysms (n = 27) and stenoses (n = 3). In the acute phase (n = 12), aneurysms were detected in 5 children (18 segments).

CONCLUSION

CTCA allows comprehensive evaluation of coronary arteries in children with KD.

Computed tomography predict regression of coronary artery aneurysm in patients with Kawasaki disease

BACKGROUND/PURPOSE

The study evaluated possible factors influencing the regression of coronary artery aneurysm (CAA) in patients with Kawasaki disease (KD) through electrocardiographically gated cardiac computed tomography (CT).

METHODS

18 patients with KD exhibited CAAs in at least 2 CT examinations conducted from December 2004 to September 2015, and 37 aneurysms were observed. Every aneurysm was corrected through the descending aorta at the origin level of the left main coronary artery under a normal distribution and measured under a fixed window level. These aneurysms were divided into 2 groups according to regression. Clinical symptoms, laboratory data, and imaging characteristics of both groups were analyzed.

RESULTS

All the aneurysms of 4 patients decreased in size, and totally, 14 aneurysms (37%) regressed. CAA regression tends to occur early after disease onset. No significant differences were observed in sex, aneurysm location, and the distance to the orifice between the 2 groups. The aneurysms with no calcification (p = 0.012), smaller diameter (p = 0.004), younger disease onset age (p = 0.048), and ectatic shape (p < 0.001) were more likely to regress according to univariate analysis. Receiver operating characteristic analysis revealed that the possible cut-off point of the maximal diameter to yield the highest sensitivity (91.3%) and specificity (92.9%) to predict CAA regression was 5.6 mm.

CONCLUSION

Calcified CAAs in patients with KD was less likely to regress. The aneurysm size and shape as well as disease onset age were possible factors influencing regression.

Diagnosis, Treatment, and Long-Term Management of Kawasaki Disease: A Scientific Statement for Health Professionals From the American Heart Association

BACKGROUND

Kawasaki disease is an acute vasculitis of childhood that leads to coronary artery aneurysms in ≈25% of untreated cases. It has been reported worldwide and is the leading cause of acquired heart disease in children in developed countries.

METHODS AND RESULTS

To revise the previous American Heart Association guidelines, a multidisciplinary writing group of experts was convened to review and appraise available evidence and practice-based opinion, as well as to provide updated recommendations for diagnosis, treatment of the acute illness, and long-term management. Although the cause remains unknown, discussion sections highlight new insights into the epidemiology, genetics, pathogenesis, pathology, natural history, and long-term outcomes. Prompt diagnosis is essential, and an updated algorithm defines supplemental information to be used to assist the diagnosis when classic clinical criteria are incomplete. Although intravenous immune globulin is the mainstay of initial treatment, the role for additional primary therapy in selected patients is discussed. Approximately 10% to 20% of patients do not respond to initial intravenous immune globulin, and recommendations for additional therapies are provided. Careful initial management of evolving coronary artery abnormalities is essential, necessitating an increased frequency of assessments and escalation of thromboprophylaxis. Risk stratification for long-term management is based primarily on maximal coronary artery luminal dimensions, normalized as Z scores, and is calibrated to both past and current involvement. Patients with aneurysms require life-long and uninterrupted cardiology follow-up.

CONCLUSIONS

These recommendations provide updated and best evidence-based guidance to healthcare providers who diagnose and manage Kawasaki disease, but clinical decision making should be individualized to specific patient circumstances.

Kawasaki disease and giant coronary artery aneurysms: the role of echocardiography from diagnosis through follow-up

Kawasaki disease is an acquired vasculitis that can affect the coronary arteries placing the patient at risk for coronary artery thrombosis, myocardial ischemia and infarction. The risk of complications related to coronary artery involvement persists for years despite recovery from the acute illness phase. The risk of late coronary disease progression necessitates long term follow-up generally accomplished by non-invasive echocardiography in pediatric patients. We review the utility of echocardiography in patients with Kawasaki disease as it relates to initial management, risk stratification and follow-up of these children.

Coronary artery abnormalities in Kawasaki disease: comparison between CT and MR coronary angiography

BACKGROUND

Although CT coronary angiography (CTCA) and MR coronary angiography (MRCA) are increasingly used in patients with Kawasaki disease, comparison of coronary artery assessibility and diagnostic performance between the two imaging modalities has been rarely performed.

PURPOSE

To investigate which imaging modality, CTCA or MRCA, is better for evaluating coronary artery abnormalities in patients with Kawasaki disease.

MATERIAL AND METHODS

Between 2003 and 2011, 56 patients (38 boys/men; age range, 1-24 years) with Kawasaki disease underwent CTCA or MRCA (group A). Of these, 17 underwent both CTCA and MRCA (group B). Visibility of 11 coronary arterial segments in each patient was graded on a four-point scale. Coronary artery aneurysm, stenosis, and occlusion were evaluated by CTCA and MRCA, based on a reference standard obtained from cardiac catheterization, echocardiography, follow-up CTCA and MRCA, and clinical history. Coronary artery assessibility and diagnostic performance were compared between CTCA and MRCA.

RESULTS

In per-segment analysis, more segments were assessable on CTCA than on MRCA in both groups. In per-patient analysis of group B, no significant difference in the assessibility was found between CTCA (95.0%, 128.3/135 segments) and MRCA (92.4%, 124.8/135 segments) (P > 0.05). Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of CTCA vs. MRCA were 93.1% vs. 77.9% (P < 0.001), 99.2% vs. 99.7% (P = 0.65), 96.8% vs. 98.7% (P = 0.65), 98.2% vs. 94.1% (P < 0.001), and 98.0% vs. 94.9% (P = 0.008), respectively, in group A, and 91.8% vs. 70.4% (P < 0.001), 99.5% vs. 99.5% (P = 1.000), 98.5% vs. 98.0% (P = 1.000), 97.2% vs. 91.1% (P = 0.006), and 97.6% vs. 92.3% (P = 0.004), respectively, in group B.

CONCLUSION

Although CTCA and MRCA show comparable assessibility in per-patient analysis, CTCA shows higher diagnostic performance than MRCA for evaluating coronary artery abnormalities in patients with Kawasaki disease.

Application of prospective ECG-triggered dual-source CT coronary angiography for infants and children with coronary artery aneurysms due to Kawasaki disease

OBJECTIVES

The aim of this study was to prospectively evaluate the initial application and value of prospective electrocardiogram (ECG)-triggered dual-source CT coronary angiography (DSCTCA) in the diagnosis of infants and children with coronary artery aneurysms due to Kawasaki disease.

METHODS

19 children [12 males; mean age 13.47 months, range 3 months to 5 years; mean heart rate 112 beats per minute (bpm), range 83-141 bpm] underwent prospective ECG-triggered DSCTCA with free breathing. Subjective image quality was assessed on a five-point scale (1, excellent; 5, non-diagnostic) by two blinded observers. The location, number and size of each aneurysm were observed and compared with those of transthoracic echocardiography (TTE) performed within 1 week. Interobserver agreement concerning the subjective image quality was evaluated with Cohen's κ-test. Bland-Altman analysis was used to evaluate the agreement on measurements (diameter and length of aneurysms) between DSCTCA and TTE. The average effective dose required for DSCTCA was calculated for all children.

RESULTS

All interobserver agreement for subjective image quality assessment was excellent (κ=0.87). The mean ± standard deviation (SD) aneurysm diameter with DSCTCA was 0.76 ± 0.36 cm and with TTE was 0.76 ± 0.39 cm. The mean ± SD aneurysm length with DSCTCA was 2.06 ± 1.35 cm and with TTE was 2.00 ± 1.22 cm. The Bland-Altman plot for agreement between DSCTCA and TTE measurements showed good agreement. The mean effective dose was 0.36 ± 0.06 mSv.

CONCLUSION

As an alternative diagnostic modality, prospective ECG-triggered DSCTCA with excellent image quality and low radiation exposure has been proved useful for diagnosing infants and children with coronary artery aneurysms due to Kawasaki disease.

ADVANCES IN KNOWLEDGE

Prospective ECG-triggered DSCTCA for infants and children allows rapid, accurate assessment of coronary aneurysms due to Kawasaki diseases, compared with TTE.

Adolescent Kawasaki disease: usefulness of 64-slice CT coronary angiography for follow-up investigation

BACKGROUND

Kawasaki disease (KD) is a systemic vasculitis that mainly affects coronary arteries in children, and requires regular follow-up from the time of diagnosis.

OBJECTIVE

To evaluate the feasibility of 64-slice CT angiography (CTA) for follow-up of patients with KD using previously performed invasive catheter coronary angiography (CCA) as reference standard.

MATERIALS AND METHODS

The study group comprised 12 patients (age 17.6 ± 2.9 years, mean ± SD) with a diagnosis of KD and a previously performed CCA (interval, 32.6 ± 13.5 months) who underwent 64-slice cardiac CTA. The quality of the images for establishing the presence of coronary abnormalities was determined by two observers. The CTA findings were compared with those from the prior CCA.

RESULTS

Adequate image quality was obtained in all patients. Mean effective dose for CTA was 6.56 ± 0.95 mSv. CTA allowed accurate identification, characterization and measurement of all coronary aneurysms (n = 32), stenoses (n = 3) and occlusions (n = 9) previously demonstrated by CCA. One patient with disease progression went on to have percutaneous coronary intervention.

CONCLUSION

Coronary lesions were reliably evaluated by 64-slice CTA in the follow-up of compliant patients with KD, reducing the need for repeated diagnostic invasive CCA. Hence, in an adequately selected patient population, the role of CCA could be limited almost only to therapeutic procedures.

Comparison study of echocardiography and dual-source CT in diagnosis of coronary artery aneurysm due to Kawasaki disease: coronary artery disease

The identification of coronary artery aneurysm (CAA) in the acute and chronic phase of the disease is of prime importance for assessing the likelihood of acute lesions and cardiovascular sequelae. Occasionally, recognition of distal coronary artery has been proven challenging by traditional echocardiography. Our purpose was to evaluate the clinical application of two-dimensional echocardiography (2DE) for detecting CAA caused by Kawasaki disease (KD) and compare with dual-source computed tomography (DSCT). A total of 24 patients with known KD and CAAs were studied by two imaging modalities, i.e., 2DE and DSCT; that is to say, the number, position, shape, and size of each CAA and its association with thrombus, were detected first from echocardiography and then compared with those obtained from DSCT performed on the same day. Meanwhile the diameters of all coronary segments were measured for each patient. Giant aneurysms (GAs) were detected in 5 patients, small and medium coronary aneurysms were identified in 19 patients. The 2DE and DSCT have the same results of proximal coronary artery, whereas conclusion of our comparison of coronary artery visualization indicated that DSCT provided more explicit distal coronary artery than 2DE. A mural thrombus could be clearly delineated in the GAs by DSCT. The 2DE has been demonstrated to be an accurate technique to quantify CAAs in KD. However, DSCT is superior to 2DE for distal coronary artery visualization. Therefore, a combination of echocardiography and DSCT can offer an overview of coronary artery anatomy.

Diagnostic application of multidetector-row computed tomographic coronary angiography to assess coronary abnormalities in pediatric patients: comparison with invasive coronary angiography

BACKGROUND

Multidetector-row computed tomographic (MDCT) coronary angiography has been validated for noninvasive assessment of coronary anatomy. However, we have less experience in diagnosing children with congenital or acquired coronary artery abnormalities by MDCT. We compared the results of MDCT with invasive coronary angiography (ICA) on identifying coronary abnormalities in infants, children, and adolescents with coronary artery abnormalities, including aneurysm, coronary fistula, or anomalous left coronary artery from pulmonary artery (ALCAPA).

METHODS

From January 2002 to December 2009, patients with congenital or acquired coronary abnormalities underwent either ICA, MDCT, or both studies for assessment of coronary anatomy. We reviewed all patients' clinical diagnosis, coronary abnormalities identified by MDCT or ICA, and analyzed the advantages and disadvantages between those two methods.

RESULTS

Thirty-three patients (20 males and 13 females) with a mean age of 10.3 years (range: 18 days to 25 years) had coronary abnormalities, including coronary artery aneurysm in Kawasaki disease (n=15), coronary artery fistula (n=12), myocardial bridge (n=2), and ALCAPA (n=4). In 17 patients only referred for ICA, 5 coronary aneurysms (3 on left main coronary artery, 1 on left anterior descending artery segment proximal, 1 on right coronary artery segment proximal), 11 coronary artery fistulas, and 2 ALCAPAs were detected. Sixteen patients received MDCT study, and 14 coronary artery aneurysms (4 on right coronary artery, 5 on left main coronary artery, 4 on left anterior descending artery, 1 on left circumflex artery), 3 myocardial bridges, 1 coronary artery fistulas, and 2 ALCAPAs were assessed. Ten patients with Kawasaki disease-related coronary lesions received MDCT study, and totally 102 (78.5%) segments permitted visualization with accurate diagnostic image quality. In this study, there were 11 patients with indication for conventional ICA spared invasive angiography after precise assessment by MDCT.

CONCLUSION

We conclude that MDCT is a good and useful modality for assessment of congenital or acquired coronary abnormalities in pediatric patients. However, MDCT cannot replace invasive cardiac catheterization and ICA because of lack of therapeutic role.

CT angiography of coronary artery aneurysms: detection, definition, causes, and treatment

OBJECTIVE

This article reviews the predisposing conditions, diagnostic criteria, CT appearances, and potential complications of coronary artery aneurysms.

CONCLUSION

With the increasing use of MDCT to image the coronary arteries, aneurysms will be identified more frequently. Coronary artery aneurysms arise from a variety of causes, with CT appearance, management, and clinical course depending on the cause.

Comprehensive evaluation of Kawasaki disease with electrocardiogram-gated cardiac multidetector computed tomography

We present a case of a young woman with Kawasaki disease who was comprehensively evaluated by electrocardiograph-gated cardiac multidetector computed tomography (MDCT). MDCT disclosed 3-vessel giant coronary arterial aneurysms and associated focal apical septal myocardial pathology. This was characterized by an early enhancement defect, myocardial thinning, and hypokinesia. These findings are likely due to focal ischemic insult resulting from distal embolization of thrombus material from the giant proximal right coronary arterial aneurysms. This case illustrates the full capabilities of MDCT in the comprehensive evaluation of Kawasaki disease.

Assessment of coronary artery lesions in children with Kawasaki disease: evaluation of MSCT in comparison with 2-D echocardiography

BACKGROUND

Transthoracic two-dimensional echocardiography is an effective method for detecting coronary arterial injury in Kawasaki disease. However, its accuracy in the diagnosis of coronary arterial lesions is limited.

OBJECTIVE

To investigate the value of multislice spiral CT for coronary angiography for observing the coronary arterial injury caused by infantile Kawasaki disease.

MATERIALS AND METHODS

Coronary angiography, using a 64-slice spiral CT scanner, and 2-D echocardiography were performed in 48 children with Kawasaki disease in whom the position, internal diameter, and length of each coronary artery were measured.

RESULTS

MSCT showed coronary artery injury in 15 of the 48 children. Among these 15 children, 20 coronary artery branches showed complications, including the left coronary artery branches in 15 (31.2%) and the right coronary artery branches in 5 (10.4%). Complications in the left coronary artery branches included dilation in 12 (25.0%) and stenosis, calcification and the combination of the two in one each, and the right coronary artery branches showed dilation; two branches also showed beaded changes. MSCT also showed dilation in the left anterior descending arteries in two children. These children showed no abnormality on 2-D echocardiography.

CONCLUSION

MSCT is a valuable examination method for detecting coronary artery injury in Kawasaki disease.

Pediatric 64-MDCT coronary angiography with ECG-modulated tube current: radiation dose and cancer risk

OBJECTIVE

The purpose of our study was to measure the radiation dose from ECG-gated CT coronary angiography in children and to estimate the cancer risk associated with the radiation dose.

MATERIALS AND METHODS

Organ doses were measured with a 5-year-old pediatric phantom and thermoluminescent dosimeters on a 64-MDCT scanner. Four retrospectively ECG-gated CT coronary angiography protocols with four simulated heart rates and the corresponding pitches were studied. The lifetime attributable risk of cancer incidence was estimated for children in the United States and Hong Kong according to the National Academies Biologic Effects of Ionizing Radiation VII report.

RESULTS

The effective doses were 16.45, 12.17, 11.97, and 11.81 mSv for the four protocols, respectively. The corresponding lifetime attributable risks estimated for 5-year-old U.S. boys and girls were 0.14%-0.20% and 0.43%-0.60%, respectively, and for 5-year-old Hong Kong boys and girls were 0.22%-0.33% and 0.61%-0.85%. In relation to the total cancer incidence (baseline cancer incidence plus lifetime attributable risk), lifetime attributable risk from radiation exposure contributed up to 0.99% and 3.51% for Hong Kong boys and girls and up to 0.46% and 1.57% for U.S. boys and girls.

CONCLUSION

Our results suggest that radiation dose and cancer risk of CT coronary angiography to pediatric patients are not negligible, more so in Hong Kong children than in U.S. children. Therefore, these examinations should be well justified clinically.

Kawasaki Disease update

Kawasaki Disease is rapidly becoming the most common cause of acquired heart disease in children in both the developed and developing world. Its etiology remains a mystery but important progress has been made in characterizing the features of the arterial wall and myocardial pathology and long-term clinical consequences. New treatments aimed at modifying the host immune response are currently under study. The genetic influence on susceptibility and disease outcome is an area of active research.

How to image Kawasaki disease: A validation of different imaging techniques

Kawasaki disease contributes to coronary artery aneurysm in 25% of patients. Cardiovascular imaging has an important role in diagnosis and follow-up of these cases. Echocardiography is the bedside technique of choice during the acute phase of the disease. MRI can be a valuable tool especially in adolescents, where sometimes echocardiography fails to detect coronary abnormalities and it has also the advantage of simultaneous perfusion, function and viability evaluation. If MRI is not available, a combination of echocardiography and SPECT gives an overview of anatomy, function and perfusion. MSCT is of limited value for follow-up because of radiation and the misleading data due to coronary calcifications. X-ray coronary angiography is kept mainly for cases where an invasive procedure should be performed.

Usefulness of 64-slice MDCT for follow-up of young children with coronary artery aneurysm due to Kawasaki disease: initial experience

To evaluate the initial application and value of 64-slice multidetector computed tomography as an alternative diagnostic modality in the follow-up of young children with coronary artery aneurysm due to Kawasaki disease. Twelve boys (mean age 5.1 years, range 1.8-7.8 years) for follow-up (time range from 1.1 to 5.1 years) of known Kawasaki disease and coronary artery aneurysm underwent 64-slice MDCT ECG-gated coronary angiography. All data were acquired without breath holding. Two pediatric radiologists independently assessed image quality and the diameter of all coronary segments were measured for each patient. The number, position, shape and size of each coronary artery aneurysm were observed and compared with those of ECHO performed previously. A total of 118/156 segments permitted visualization with diagnostic image quality, the CT measurements showed good inter-observer and intra-observer reliability, coefficients were 0.93 and 0.88, respectively. A total of 30 coronary artery aneurysms were identified with measured mean of 7.5+/-3.8 mm in diameter, and of 12.4+/-9.1 mm in longitudinal lengths.10 tumors were small, 8 tumors were medium and 12 tumors were giant aneurysm. The affected segments included LM7/12(58.3%), 9/12(75%) of LAD1, 4/12(33.3%) of LAD2, 2/12(16.7%) of LCX1; 6/12(50%) of RCA1, 9/12(75%) of RCA2 and 4/12(33.3%) of RCA3, including affected two segments in 9 tumors and three segments in 1 tumor. Calcifications were found in 5 aneurysms and 3/5 with thrombosis; six stenotic segments were found. ECHO failed to detect 8 tumors with 2/8 in LAD, 1/8 in LCX and 5/8 in RCA, and those included 4 small aneurysms. The use of 64-slice MDCT angiography proved valuable for monitoring young children with Kawasaki disease. However, further study is necessary to specify the sensitivity and specificity of MDCT in the follow-up.

Coronary artery diameters in infants and children with congenital heart disease as determined by computed tomography

This study was conducted to establish reference curves and formulas for the diameters of the coronary arteries in infants and children using computed tomography. A total of 145 children (57 female, 88 male) ranging in age from 2 days to 19 years, 11 months (mean 5 years, 10 months), were retrospectively identified, and the diameters of their coronary arteries were quantified. The measurability of the coronary arteries, coronary arterial size differences between the genders, and relations of the diameters of the coronary arteries to age, height, weight, body surface area, and the diameter of the descending aorta were examined. Independent-samples Student's t tests, 2-tailed Pearson's correlations, and linear regression were used in statistical analysis. The measurability of all coronary arteries was 73.3%. No difference in coronary arterial size was found between the genders. The diameter of the descending aorta correlated most strongly with coronary arterial size. In conclusion, predictive formulas and reference curves for coronary arterial diameters in infants and children were obtained.

Visualization of coronary arteries in patients after childhood Kawasaki syndrome: value of multidetector CT and MR imaging in comparison to conventional coronary catheterization

BACKGROUND

After childhood Kawasaki syndrome (KS) the coronary arteries undergo a lifelong dynamic pathological change, and follow-up coronary artery imaging is essential. At present, conventional coronary catheterization (CCC) and angiography is still regarded as the gold standard. Less-invasive methods such as multidetector CT angiography (MDCT-A) and MRI have been used sporadically.

OBJECTIVE

To compare the diagnostic quality of MDCT-A and MRI with that of CCC for coronary imaging in a group of patients with coronary artery pathology after childhood KS.

MATERIALS AND METHODS

A total of 16 patients (aged 5-27 years) underwent CCC and 16-row MDCT-A and 14 patients MRI (1.5 T).

RESULTS

There was 100% agreement between MDCT-A and CCC in the detection of coronary aneurysms and stenoses. MDCT-A was superior for the visualization of calcified lesions. MRI and CCC showed 93% agreement for the detection of aneurysms. Visualization of coronary artery stenoses was difficult using MRI-one stenosis was missed.

CONCLUSION

MDCT-A has excellent correlation with CCC regarding all changes affecting the coronary arteries in the follow-up of childhood KS. In comparison to MDCT-A and CCC, MRI is less precise in the detection of stenotic lesions. Due to its high image quality and ease of performance MDCT-A should be the primary diagnostic modality in patients following childhood KS.

Imaging studies in the diagnosis and management of vasculitis

The term vasculitis encompasses a number of distinct clinicopathologic disease entities. Final diagnosis should be supported by histologic study in most cases. However, different imaging modalities offer the potential for an early visualization of inflammatory vascular abnormalities, provide some diagnostic clues, and allow for an adequate assessment of therapeutic response. This review discusses recent advances in imaging techniques and refinements in vascular imaging methods, as well as a brief mention of research modalities that are increasingly used in studies of pathogenesis or in the assessment of disease progression.