Scientific Exhibit Authors:

Transcription

1 Preoperative evaluation of infants and children with congenital heart disease with ECG triggered 128 Dual Source CT Angiography- Portugal- Angola collaboration Poster No.: C-0942 Congress: ECR 2013 Type: Scientific Exhibit Authors: J. Costa, A. Proença Ramos, J. C. A. Costa, V. Silva, C Gomes, R. Muingilu, M. R. Goncalves ; Bruxelles/BE, Viana do 3 Castelo/PT, Luanda/AO Keywords: Cardiac, CT-Angiography, Echocardiography, Catheter arteriography, Acceptance testing, Congenital DOI: /ecr2013/C-0942 Any information contained in this pdf file is automatically generated from digital material submitted to EPOS by third parties in the form of scientific presentations. References to any names, marks, products, or services of third parties or hypertext links to thirdparty sites or information are provided solely as a convenience to you and do not in any way constitute or imply ECR's endorsement, sponsorship or recommendation of the third party, information, product or service. ECR is not responsible for the content of these pages and does not make any representations regarding the content or accuracy of material in this file. As per copyright regulations, any unauthorised use of the material or parts thereof as well as commercial reproduction or multiple distribution by any traditional or electronically based reproduction/publication method ist strictly prohibited. You agree to defend, indemnify, and hold ECR harmless from and against any and all claims, damages, costs, and expenses, including attorneys' fees, arising from or related to your use of these pages. Please note: Links to movies, ppt slideshows and any other multimedia files are not available in the pdf version of presentations. Page 1 of 26

2 Purpose Congenital heart diseases (CHD) is the most common inborn defect (incidence of 1% approximately) with significant impact on morbidity, mortality, and healthcare costs. Reported total CHD worldwide birth prevalence reached a stable estimate of 9 per 1000 live births in the last 15 years [1]. A recent systematic review of 114 papers and Meta-analysis found significant geographic differences in CHD birth prevalence. Genetic, environmental, socio-economical, ethnic aspects as well as limited access to health care in many parts of the world or scarce data from developing countries may play a role in these differences. In Europe the CHD prevalence is approximately 8 per 1000 live births, higher than in North America (7 per 1000 live births) [1]. The American Heart Association estimated last year that approximately 25% of infants affected by CHD in the United States require invasive treatment in the first year of life. The most common types of CHD at birth are ventricular septal defect (30%), atrial septal defect (10%), patent ductus arteriosus (10%), pulmonary stenosis (7%), aortic stenosis (6%), tetralogy of fallot (6%) and transposition of the great arteries (4%) [2]. In pre-operative evaluation, transthoracic echocardiography is the first imaging modality [3]. Nevertheless extracardiac structures such as the great arteries and great veins as well as complex intracardiac connections may be difficult to resolve by ultrasound [3]. Diagnostic cardiac catheterization, being an invasive technique, has its own risk of complications and can be limited in providing accurate anatomical information. CT angiography (CTA) plays an important supplementary role to ultrasound, allowing an accurate assessment of normal and pathologic anatomic features. It serves also as a road map to surgical intervention. The purpose of this study was to diagnose and evaluate the characteristics of congenital heart disease with 128-slice dual source CTA in a paediatric population of 59 patients referred to the Girassol Clinic at Luanda - Angola for surgical treatment, from May 2011 to May A second purpose was to compare the mean radiation dose (DLP and effective dose) of this series with doses used in daily practice referred in recent literature. Page 2 of 26

3 Methods and Materials Patients Informed consent and institutional board approval were obtained. Fifty-nine patients (53% male and 47% female) with CHD were referred by the National Health Service of Angola to the Girassol Clinic at Luanda - Angola for surgical treatment and underwent low-dose prospective ECG-triggering DSCT angiography. Patients were included if they met the following criteria: sinus rhythm in ECG, no known contraindications to iodinated contrast media administration and no history of renal insufficiency. Acquisition Protocol Patients underwent general inhalational anaesthesia, with spontaneous ventilation, using sevoflurane (3% to 5%) through a facemask. The concentration of oxygen administered varied according to the type of congenital heart disease - cyanotic or non-cyanotic. In all patients, vital parameters monitoring during anaesthesia included non-invasive measurement of blood pressure, heart rate, arterial oxygen saturation and capnography. After inhalational induction, central or peripheral venous access was placed for contrast administration. For every patient, a baseline heart rate was recorded before CT acquisition. Intravenous b-blocker (metoprolol) was administered when heart rate was superior to 120 bpm and in absence of contraindications. The dose of metoprolol ranged from 0.1 to 0.2 mg/ kg. A clear QRS complex was obtained before CT acquisition. Contrast was administered by an automated double head injector at a flow rate of 1.2 ml/s, followed by 50 ml of saline solution at the same rate. The volume of non-ionic iodinated contrast (Iopromide 370 mg I/mL) ranged between ml/kg. We used a bolus tracking technique and the region of interest (ROI) was placed in the descending intra-thoracic aorta Page 3 of 26

4 The triggering threshold for bolus tracking depended on the arm's side of the venous access due to different length of subclavian veins: 90 UH if it was a left side access and 80 UH if it was right. Using the Dual Source 128-CT, the fixed start delay is 6 seconds. No additional delay was added. As heart rates in paediatric population are almost always superior to 70 bpm, even with prior b-blockers administration, use of Helical Acquisition Mode was not possible. The CT acquisition mode was the ECG triggered sequential mode, the so-called Adaptive Cardio Sequence Mode. In this mode there is an adjustable acquisition window, allowing to chose an interval of the cardiac cycle for CT acquisition, instead of just one precisely phase as happened with the classic sequential mode. This gives to CT operator the opportunity of free phase shifting in post-processing reconstruction, if extra-systole or patient movement has disturbed some part of acquisition. Besides, as we can adjust the acquisition window, if we decrease it, the radiation dose will be lower. Images were reconstructed with a section thickness of 0.75 mm and overlapping of 0.4 mm. The table I summarizes the examination protocol for a left side venous access. Post-processing Various image data post-processing techniques were performed, including maximum intensity projection (MIP) with 3 mm of slice thickness, and volume rendering (VRT), at a workstation equipped with dedicated software. Page 4 of 26

5 Images for this section: Table 1: Example of examination protocol for a left side venous access. Department of Radiology, Girassol Clinic, Luanda/ Angola Page 5 of 26

6 Results From the 59 patients purposed to surgical treatment, CTA identified thirty eight cases of Tetralogy, two cases of Aortic Coarctation, one case of Aortic Arch Interruption, four Truncus Arteriosus, one Ebstein Anomaly, two Transpositions of Great Arteries, ten Stenosis/ Agenesis, one Aortopulmonary Window, nine Patent Ductus Arteriosus, two cases of Dextrocardia, one Double Outlet Right ventricle and one Ventricular Tumor. All cases were confirmed at surgery, if indicated, or with angiography and echocardiogram. Mean age of patients was 31 months (range between 13 days - 12 years) and mean weight 8.37 kg. The baseline heart rate ranged between 51 and 149 bpm. Mean dose-length product was mgy cm and mean calculated effective dose was 2.4 msv (DLP ranged between mgy cm and Effective dose between msv). Ten cases are presented here: one Aortic Interruption (Fig.1), two Tetralogies of (Fig.2 and Fig.3), two Truncus Arteriosus, one type I and another type II, according to Collet and Edwards classification (Fig. 5 and Fig. 6), one Transposition of the Great Arteries (Fig. 7), one Unilateral Agenesis with bilateral major aortopulmonary collaterals (MAPCAs) (Fig. 8 and Fig. 9), one Aortopulmonary Window (Fig. 10 and Fig. 11), one Patent Ductus Arteriosus (Fig. 12) and one Ebstein Anomaly (Fig.13). Patient Age Weigh Contrast HR DLP (mgy cm) Eff. Dose (msv) Pathology 1 3w 3.4 kg 5 ml TGA +VSD Aortic Arch Interruption +PDA 2 3y 8 kg 13 ml m 4.4 kg 6 ml Left Ventricular Tumor Page 6 of 26

7 4 7m 7.5 kg 11 ml MAPCAs 5 13 m 6.7 kg 10 ml Right Aortic Arch m 4.9 kg 7 ml Absent Valve Stenosis 7 8m 7 kg 10 ml Aortic Coarctation +PDA 8 3m 5.4 kg 8 ml with Main and Left Stenosis 9 5y 14 kg 12 ml y 13 kg 10 ml Absent Valve Stenosis 11 2y 6 kg 10 ml Aortic Coarctation +PDA 12 2y 9.8 kg 10 ml Dextrocardia Atresia of Tricuspid Single Ventricle Discordant Page 7 of 26

8 Ventriculoarterial Connections y 16 kg 27 ml y 10.6 kg 18 ml Bilateral MAPCAs y 20 kg 25 ml Left Hypoplasia +Right Agenesis +MAPCAs 16 2y 10.5 kg 17 ml m 7 kg 12 ml y 6 kg 10 ml Truncus Arteriosus 19 3y 7 kg 11 ml with Bilateral Stenosis y 35 kg 35 ml with Stenosis 21 2y 8.2 kg 10 ml Stenosis + VSD 22 3y 7 kg 11 ml ASD + VSD Stenosis Page 8 of 26

9 23 2m 3.5 kg 6 ml Hemitruncus Arteriosus + VSD Right Aortic Arch 24 2w 1.9 kg 3 ml Truncus Arteriosus type I Bicuspid Aortic Valve 25 2y 6 kg 10 ml Left Agenesis MAPCAs 26 5w 3.8 kg 6 ml Truncus Arteriosus type II Right Aortic Arch 27 2y 6 kg 10 ml y 8 kg 13 ml m 6.8 kg 11 ml d 2.8 kg 4.5 ml with Bilateral Stenosis 31 5m 6 kg 10 ml y 8.2 kg 10 ml Hipoplasia + VSD 33 3m 3 kg 5 ml with Left Stenosis Right Page 9 of 26

10 Aortic Arch 34 2y 4 kg 6 ml y 7 kg 12 ml y 22 kg 25 ml Left Agenesis +MAPCAs 37 7y 20 kg 24 ml y 7.4 kg 12 ml y 9 kg 15 ml y 8 kg 14 ml TGA + VSD Dextrocardia m 9 kg 11 ml y 30 kg 45 ml Ebstein Anomaly m 9.4 kg 11 ml Right Aortic Arch m 10 kg 10 ml m 4.5 kg 5 ml with Stenosis + Bicuspid Valve d 3 kg 4 ml m 7.4 kg 9 ml y 8.6 kg 10 ml m 6.5 kg 8 ml Page 10 of 26

11 50 14 m 8 kg 9 ml d 4 kg 5 ml m 3 kg 3.5 ml Aortopulmonary Window 53 1y 4.5 kg 7 ml Left Stenosis + PDA +VSD 54 1y 7.7 kg 13 ml VSD multiple + Overriding Aorta+ PDA 55 4y 8 kg 13 ml Double Outlet Right Ventricle Stenosis VSD + MAPCAs 56 5y 7 kg 11 ml VSD +PDA +Left Agenesis +MAPCAs 57 6m 5.7 kg 7 ml d 4 kg 5 ml Stenosis + VSD 59 3w 2.8 kg 5 ml Right Aortic Arch + Left Page 11 of 26

12 Agenesis Table 2. Total of patients with CHD that underwent DS-CTA, between May 2011 and May 2012, and respective pathologies diagnosed by this imaging method. Age: d-days, w-weeks, y-years. Pathologies: TGA - transposition of the great arteries, VSD - ventricular septal defect, PDA - patent ductus arteriosus, MAPCAs - major aortopulmonary collateral arteries, ASD - atrial septal defect. Page 12 of 26

13 Images for this section: Fig. 1: Aortic arch interruption type A in a new born of 21 days. There is a complete lack of anatomic continuity (red line) between the aortic arch after left subclavian artery (lsa) origin - aortic isthmus and descending thoracic aorta (da). Patent ductus arteriosus (PDA) is always present and links the descending thoracic aorta to the main pulmonary artery (mpa). In this case PDA is very large in proximal and middle parts, and stenotic at the junction point with descending aorta (arrow). This can mimic an aortic coarctation. Right pulmonary artery (rpa) and left pulmonary artery (lpa). MIP (a) and VRT reconstructions images (b). Department of Radiology, Girassol Clinic, Luanda/ Angola Page 13 of 26

14 Fig. 2: Tetralogy of in a child of 3 years. MIP reconstructions images showing the overriding aorta over the ventricular septal defect (c) infundibular stenosis (d, arrow). The coronary arteries have a normal origin (a,b). Note that right coronary artery (a) has no major marginal branches crossing the infundibulum as well as the normal traject of left anterior descending artery (b). These are important information data for the cardiothoracic surgeon, as he will do a right ventriculotomy for infundibular stenosis repair. Department of Radiology, Girassol Clinic, Luanda/ Angola Page 14 of 26

15 Fig. 3: Tetralogy of in 3-month-old infant. MIP reconstructions images showing the overriding aorta over the ventricular septal defect (a). MIP (b) and VRT (c) reconstruction images showing common pulmonary artery stenosis (red arrow) and left pulmonary stenosis (white arrow). Department of Radiology, Girassol Clinic, Luanda/ Angola Fig. 5: Truncus arteriosus (TA) type I of the Collet and Edwards classification. The pulmonary arteries originate as a single main pulmonary artery (mpa) from the lateral aspect of the TA. Ascending aorta (aa). MIP reconstruction (a) showing also the ventricular septal defect (asterisk). Anterior and posterior views of VRT reconstruction (b,c). Department of Radiology, Girassol Clinic, Luanda/ Angola Page 15 of 26

16 Fig. 6: Truncus arteriosus (TA) type II of the Collet and Edwards classification, where pulmonary arteries (lpa and rpa) originate independently from the postero-lateral aspect of the TA. Ascending aorta (aa), inferior vena cava (IVC). MIP reconstruction images showing the origin of aorta and pulmonary arteries from truncus arteriosus in the axial plan (a), the origin of aorta and right pulmonary artery (b) and the very close but separate emergence of pulmonary arteries from TA (c). Department of Radiology, Girassol Clinic, Luanda/ Angola Page 16 of 26

17 Fig. 7: Transposition of the great arteries and associated dextrocardia. MIP reconstruction image (a) showing the ascending aorta (aa) in a anterior position to the pulmonary artery (PA). The aortic valve is normal with three leaflets. The coronary arteries arise in the normal position. MIP reconstructions images (b,c) showing the origin of aorta from the morphologic right ventricle (RV) (b) and the origin of the main pulmonary artery (PA) from the morphologic left ventricle (LV) (c) - ventriculoarterial discordant connections. Associated ventricular septal defect (asterisk). Anterior oblique left view of VRT reconstruction (d). Department of Radiology, Girassol Clinic, Luanda/ Angola Page 17 of 26

18 Fig. 8: Right pulmonary artery agenesis and left pulmonary artery hypoplasia with bilateral major aortopulmonary collateral arteries (MAPCAs) in a patient with Tetralogy of. In this case MAPCAs are very developed - they arise from the initial part of the descending aorta, acquire a circuitous route in upper mediastinum (red arrows) before approaching both pulmonary hila (a,b). Department of Radiology, Girassol Clinic, Luanda/ Angola Page 18 of 26

19 Fig. 9: Right pulmonary artery agenesis and left pulmonary artery hypoplasia with bilateral major aortopulmonary collateral arteries (MAPCAs) in a patient with Tetralogy of. VRT reconstruction image (c) showing the origin of MAPCAs from descending thoracic aorta. Department of Radiology, Girassol Clinic, Luanda/ Angola Page 19 of 26

20 Fig. 10: Aortopulmonary window in a new born of one month old. MIP reconstruction images (a,b) showing the communication (asterisk) between the ascending aorta and the main pulmonary artery, close to the orifice of the left coronary artery, and in the presence of two semilunar valves. As there is very little length to the communication the term «window» is used. The origin of coronary arteries was normal (not shown). Department of Radiology, Girassol Clinic, Luanda/ Angola Page 20 of 26

21 Fig. 11: Aortopulmonary window in a new born of one month old. VRT reconstruction image showing the "window" (asterisk) between ascending aorta and main pulmonary artery, close to their emergence (c). Department of Radiology, Girassol Clinic, Luanda/ Angola Page 21 of 26

22 Fig. 12: Patent ductus arteriosus (arrow). MIP reconstruction (a) and anterior oblique left view of VRT reconstruction (b) shows that the ductus connects aortic arch, after the emergence of left subclavian artery, to the left pulmonary artery. Department of Radiology, Girassol Clinic, Luanda/ Angola Page 22 of 26

23 Fig. 13: Ebstein anomaly in a ten years old child. MIP reconstruction image showing the displacement of the septal and posterior leaflets of the tricuspid valve towards the apex of the right ventricle (arrows), right atrium dilatation as well as the large atrialized portion of the right ventricle. Note the left intraventricular hypodensity coming from the septal wall, which can corresponds to a thrombus vs. ventricular tumor (asterisk). Department of Radiology, Girassol Clinic, Luanda/ Angola Page 23 of 26

24 Conclusion Congenital Heart Disease (CHD) is frequently diagnosed in the neonatal or childhood period of life. In pre-operative evaluation, CTA plays an important supplementary role, allowing an accurate assessment of normal and pathologic anatomic features, providing a road map for the surgical team. In paediatric population, radiation dose is even a more concerning issue. In our cases the mean effective dose was 2.4 msv (range msv). These are really low doses comparing to those used in daily practice CTAs referred in recent literature. In fact, the effective radiation dose for ECG-gated MDCT scanning with retrospective helical acquisition mode and ECG pulsing has been estimated as 9 msv [4]. The number of cases per year (59 patients and 28 different congenital heart diseases), their complexity and variety, as well as the multidisciplinary work between radiologists, cardiologists, anaesthetists and cardio-thoracic surgeons gives to the Girassol Clinic, a deep experience in the diagnosis and treatment of CHD. The 128-slice dual source CTA with prospective ECG - triggering protocol (the so-called Adaptive Cardio Sequence Mode) proved to be a very low-dose, effective, non-invasive method of diagnosing Congenital Heart Disease. Page 24 of 26

25 References Van der Linde D, Konings EE, et al. Birth Prevalence of Congenital Heart Disease Worldwide: a Systematic Review and Meta-Analysis. JACC 2011; 58(21): Gatzoulis MA, Swan L, et al. Adult Congenital Heart Disease: a practical guide. Oxford: Blackwell Publishing Ltd, Corno AF, Festa P. Congenital Heart Defects: Decision Making for surgery, Vol. 3 CT-Scan and MRI. Stürtz GMbH: Steinkopff Verlag Srpinger, Hansleiter J, Meyer T, et al. Radiation dose estimates from cardiac multislice computed tomography in daily practice: impact of different scanning protocols on effective dose estimates. Circulation 2006; 113: Page 25 of 26

26 Personal Information Joana Costa MD, Department of Radiology, Centre Hospitalier Universitaire de Charleroi - Hôpital Civil, Université Libre de Bruxelles, Brussels, Belgium; joanaalvescosta@gmail.com. João Carlos Costa MD, Head of the Departments of Radiology, Hospital Particular de Viana do Castelo, Viana do Castelo and Hospital Escola, Porto, Faculdade de Medicina da Universidade do Porto, Portugal; gito.jcc@gmail.com. Andreia Proença MD, Department of Radiology, Hospital Particular de Viana do Castelo, Faculdade de Medicina da Universidade do Porto, Portugal; andreia_m_ramos@hotmail.com. Vasco Silva MD, CEO of the Department of Radiology, Girassol Clinic, Luanda, Angola; vasco.silva@clinicagirassol.co.ao. Constança Gomes MD, Head of the Department of Radiology, Girassol Clinic, Luanda, Angola; constancagomes@gmail.com. Rachel Muingilu MD, Department of Radiology, Girassol Clinic, Luanda, Angola; rachelnanizeyi@hotmail.com. Marisa Gonçalves CT Radiologic Technologist, formerly Department of Radiology, Girassol Clinic, Luanda, Angola, currently Department of Radiology, Hospital Escola, Porto, Portugal; marisag.jcc@gmail.com. Page 26 of 26