Use of 4D Flow CMR to Diagnose the Cause of Desaturation in a 35-year-old Male Patient with a Classic Fontan Circulation (QF_TH_031)

Thursday, January 30, 2025

8:00 AM – 8:10 AM East Coast USA Time

Location: Blue Room PreFunction

Presenting Author(s)

MK

Masaki Kodaira, MD, PhD

Associate Professor
Keio University Hospital, Japan

Primary Author(s)

MK

Masaki Kodaira, MD, PhD

Associate Professor
Keio University Hospital, Japan

Co-Author(s)

RT

Ryo Tsukada

Deputy Chief
Keio University Hospital, Japan
SM

Shigeki Miura, RT

Technologist
Keio University Hospital, Japan
MK

Mai Kimurua, MD

Associate Professor
Keio University Hospital, Japan
NS

Naofumi Suumitomo, MD, PhD

Associate Professor
Keio University Hospital, Japan
TO

Takayuki Oyanagi, MD

Associate Professor
Keio University Hospital, Japan
TN

Takehiro Nakahara, MD, PhD

Associate Professor
Keio University Hospital, Japan
NK

Naritaka Kimura, MD, PhD

Assistant Professor
Keio University School of Medicine, Japan
HY

Hiroyuki Yamagishi, MD, PhD

Professor
Keio University School of Medicine, Japan
MJ

Masahiro Jinzaki, MD

Professor
Keio University School of Medicine, Japan
MI

Masaki Ieda, MD, PhD

Professor
Keio University Hospital, Japan

Description of Clinical Presentation: A 35-year-old male with native anatomy of tricuspid atresia had undergone aortopulmonary connection (APC) Fontan at the age of 4. He had been lost to follow-up for the last five years. He presented to another local hospital with shortness of breath and leg edema. His electrocardiogram showed atrial flutter, which was treated with electric conversion. His oxygen level was around 74% at sitting, which rose to around 90% at supine. He was referred to our hospital for further diagnostic testing and treatment.

Diagnostic Techniques and Their Most Important Findings: CMR was scanned using a 1.5 tesla CMR system(SIGNA^TM Artist, General Electric Healthcare, Wisconsin, USA). Short-axis and long-axis balanced steady-state free precession (bSSFP) cine images were acquired to assess ventricle volumes and function. Respiratory and electrocardiogram-gated 4D flow MRI CMR sequences were obtained in an axial 3D volume. Data were processed using cvi42 (version 5.9, Circle Cardiovascular Imaging, Calgary, Alberta, Canada).
There was significant right atrium enlargement and no obstruction in the Fontan pathway. 4D flow CMR showed a large amount of collateral from the right atrium leading to the upper left pulmonary veins via the coronary sinus. This 4D flow CMR image guided us when we performed the diagnostic catheter and enabled us to perform selective angiography of this collateral. We concluded that the patient was desaturating from the low cardiac output due to the APC Fontan circulation and this right-to-left collateral.

Learning Points from this Case: We successfully demonstrated a right atrium to coronary sinus to left upper pulmonary vein collateral pathway using 4D flow CMR. This collateral can be categorized as systemic venous to pulmonary venous collateral. However, to our knowledge, this specific type of collateral in a Fontan circulation has never been reported. 4D flow CMR is an effective diagnostic imaging tool for demonstrating the collaterals in the Fontan circulation.