1. Stanford University School of Medicine, Department of Pediatrics, Division of Pediatric Cardiology,
Palo Alto, CA, USA
2. Stanford University School of Medicine, Department of Radiology, Division of Cardiothoracic Imaging,
Palo Alto, CA, USA
3. Stanford University School of Medicine, Division of Cardiovascular Medicine, Palo Alto, CA, USA
Clinical History:
A 40-year-old female with a past medical history of anomalous left coronary artery from the pulmonary artery (ALCAPA) complicated by severe left ventricular dysfunction in infancy underwent Takeuchi repair consisting of creation of an aortopulmonary window
and an intrapulmonary tunnel connecting the anomalous left main coronary artery (LMCA) ostium with the aorta at 14 months. She presented to adult congenital heart disease (ACHD) care in the setting of desiring pregnancy.
Physical examination revealed a normal S1 and S2 with a harsh, mid-peaking 3/6 systolic ejection murmur heard best at the left upper sternal border. To better inform pregnancy risk, heart rhythm monitoring was ordered for palpitations and cardiopulmonary
exercise testing (CPET) was obtained to assess hemodynamic response to stress and overall fitness. Additionally, CMR was obtained to further investigate biventricular size and function, LGE (given history of late repair and historically reduced LV function), Takeuchi repair site and concern for supravalvar pulmonary stenosis on examination.
CMR Findings:
The study was performed on a 1.5 Tesla magnet (GE Optima 450W). Cine steady state free precession (SSFP, Movies 1-4) revealed normal biventricular size and systolic function (LVEDVi: 53 mL/m2, LVEF: 59%; RVEDVi: 70 mL/m2, RVEF: 61%). Narrowing of the pulmonary trunk was noted at the site of Takeuchi repair (peak velocity 3.13 m/s, peak pressure gradient 39 mmHg) with flow directed towards a post-stenotically aneurysmal left pulmonary artery (LPA) (30 x 32 mm; Movies 5-6). There was associated moderate pulmonary regurgitation (regurgitant volume: 20 mL/beat, regurgitant fraction: 25%) with holodiastolic flow reversal present in the main pulmonary artery (MPA), but not the branch pulmonary arteries. 4D flow imaging also revealed abnormal diastolic flow in the MPA arising from the aortic side of the Takeuchi tunnel directed towards the LPA (Movie 7). No ischemic late gadolinium enhancement was detected (Movie 8).
  |
  |
Movies 1-4: SSFP cine images from various projections demonstrating normal biventricular size and systolic function. Supravalvar pulmonary stenosis is noted from a long axis view of the right ventricle.
 |
Movie 5: SSFP cine image demonstrating moderate supravalvar pulmonary stenosis and moderate pulmonary regurgitation at the site of Takeuchi repair.
 |
Movie 6: 4D flow image demonstrating moderate supravalvar pulmonary stenosis and moderate pulmonary regurgitation at the site of Takeuchi repair.
 |
Movie 7: 4D flow reveals abnormal diastolic flow from the Takeuchi left main coronary baffle into the main pulmonary artery.
 |
Figure 1: Still frame image from 4D flow with baffle leak into the main pulmonary artery labeled (arrow).
 |
Movie 8: Short axis stack of delayed enhancement images without evidence of late gadolinium enhancement.
Conclusion
The patient subsequently underwent a gated coronary computed tomography angiography (CTA) as part of pre-surgical planning, which noted a 3 mm fistulous leak between the aortic side of the intrapulmonary baffle to the right side of the MPA (Figure 2). The patient had a normal hemodynamic response to stress, no ischemic ST-T changes, and achieved a peak VO2 of 19 mL/min/kg on cardiopulmonary exercise test (CPET) (peak VO2 predicted based on age and body mass using the Waserserman equation; result is 75% of her predicted peak VO2). However, more definitive testing with improved negative predictive value was deemed necessary given her desire to become pregnant in the ensuing months. A pharmacologic positron emission tomography (PET) stress test was obtained, which showed no focal epicardial territory ischemia, but globally reduced myocardial flow reserve (MFR=1.96) with regional worsening in the left anterior descending (LAD) and left circumflex (LCx) territories as well as transient ischemic dilation (1.24; normal <1.02 in females) of the left ventricle after stress. Thus, testing confirmed left coronary artery steal from her Takeuchi baffle leak with high-risk ischemic stress testing features. She underwent direct Takeuchi baffle leak repair, patch augmentation of the MPA, and bioprosthetic pulmonary valve replacement and is doing well post-operatively. Intra-operatively, a single fistulous leak from the superior aspect of the baffle, allowing steal from the left coronary artery into the MPA, was visualized and directly sutured closed.
 |
Figure 2: Gated coronary CT confirms presence of 3mm fistulous leak between the aortic side of the Takeuchi tunnel and the main pulmonary artery.
Perspective
ALCAPA is a rare congenital heart defect (CHD) in which the LMCA arises from the pulmonary artery rather than the aorta. If left untreated ALCAPA can result in ischemic cardiomyopathy or may be fatal. Both American and European ACHD guidelines give a class I indication for surgical repair of ALCAPA regardless of symptoms.[1] Surgical approach to treatment is dictated by the proximity and course of the anomalous LMCA relative to its usual origin from the left coronary cusp of the aortic root. Reimplantation of the coronary ostia, subclavian-left coronary anastomosis, coronary bypass, or the Takeuchi procedure have all been used to treat ALCAPA. The Takeuchi procedure creates an aortopulmonary window and an intrapulmonary tunnel that baffles the anomalous left coronary to the aorta. Late complications of this surgical approach are common, with baffle leaks and supravalvar pulmonary stenosis occurring most often, both of which were observed in our case.[2]
4D flow CMR increasingly has shown clinical utility in characterizing intracardiac flow patterns, more accurate and time-efficient flow quantification relative to 2D phase contrast imaging in CHD, and improved detection of CHD-related shunting not seen well by traditional imaging techniques.[3, 4] 4D flow imaging was crucial for the detection of our patient’s Takeuchi baffle leak and drastically changed clinical management in favor of surgical revision prior to planned pregnancy. PET stress testing was used provided its improved diagnostic accuracy and prognostic performance, given the addition of quantitation of myocardial blood flow.[5] Multidisciplinary discussion recommended pre-pregnancy surgical repair given the patient’s LMCA steal with transient ischemic dilation noted on stress PET testing. The patient has recovered completely from surgery and intends to conceive soon.
View the entire study on Cloud CMR
References
- Egidy Assenza G, Krieger EV, Baumgartner H, Cupido B, Dimopoulos K, Louis C, et al. AHA/ACC vs ESC Guidelines for Management of Adults With Congenital Heart Disease: JACC Guideline Comparison. J Am Coll Cardiol. 2021;78(19):1904-18.
- Ginde S, Earing MG, Bartz PJ, Cava JR, Tweddell JS. Late complications after Takeuchi repair of anomalous left coronary artery from the pulmonary artery: case series and review of literature. Pediatr Cardiol. 2012;33(7):1115-23.
- Demirkiran A, van Ooij P, Westenberg JJM, Hofman MBM, van Assen HC, Schoonmade LJ, et al. Clinical intra-cardiac 4D flow CMR: acquisition, analysis, and clinical applications. Eur Heart J Cardiovasc Imaging. 2022;23(2):154-65.
- Johnson JN, Mandell JG, Christopher A, Olivieri LJ, Loke YH, Campbell MJ, et al. Society for Cardiovascular Magnetic Resonance 2020 Case of the Week series. J Cardiovasc Magn Reson. 2021;23(1):108.
- Gulati M, Levy PD, Mukherjee D, Amsterdam E, Bhatt DL, Birtcher KK, et al. 2021 AHA/ACC/ASE/CHEST/SAEM/SCCT/SCMR Guideline for the Evaluation and Diagnosis of Chest Pain: Executive Summary: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines. Circulation. 2021;144(22):e368-e454.
Case Prepared By:
Robert D. Tunks, MD, MHS
Penn State Health Milton S. Hershey Medical Center
Hershey, PA USA
Editorial Board Member, Cases of SCMR
