Racing against time: A quality study of accelerated CMR in patients with congenital heart disease

Friday, February 6, 2026

3:45 PM - 3:52 PM

Location: Galapagos / Aruba / Ilhabela (2nd Lower Level)

Presenting Author(s)

Emilie Schalch, BSc

Medical Student
University Hospital (CHUV) and University of Lausanne (UNIL)
Lausanne, Vaud, Switzerland

Primary Author(s)

Fabienne Dirbach, MD

Physician, PhD student
Lausanne University Hospital and University of Lausanne
Lausanne, Vaud, Switzerland

Co-Author(s)

Fabienne Dirbach, MD

Physician, PhD student
Lausanne University Hospital and University of Lausanne
Lausanne, Vaud, Switzerland
AM

Ambra Masi, MD

Cardiologist
University Hospital (CHUV) and University of Lausanne (UNIL), Switzerland
Christopher W. Roy, PhD

Lecturer
Lausanne University Hospital (CHUV) and University of Lausanne (UNIL)
Lausanne, Vaud, Switzerland
PG

Paolo Garelli, MSc

PhD student
University Hospital (CHUV) and University of Lausanne (UNIL), Switzerland
DR

David Rodrigues, MSc

Deputy chief radiology technician
Lausanne University Hospital and University of Lausanne, Switzerland
MS

Matthias Stuber, PhD

Professor/Director
CIBM/CHUV/UNIL
Lausanne, Switzerland
JB

Judith Bouchardy, MD

Medical doctor
Lausanne University Hospital and University of Lausanne
Lausanne, Switzerland
ML

Magalie Ladouceur, MD

MD
University Hospital (CHUV) and University of Lausanne (UNIL), Switzerland
Juerg Schwitter, MD

Full Professor
University Hospital and University of Lausanne
Lausanne, Vaud, Switzerland
Tobias Rutz, MD

Medical doctor
University Hospital and University of Lausanne
Lausanne, Vaud, Switzerland

Background: Improved survival of patients with congenital heart disease (CHD) has led to a rapid increase in the use of cardiovascular magnetic resonance (CMR) [1]. However, conventional CMR acquisitions remain time-consuming with scan time around approx. 60min, prompting efforts to accelerate the process to meet the surge in demand. In this study we assess the implementation and efficiency of accelerated CMR trying to cut-down CMR exam duration by 30% in selected CHD patients [2]. The goal of this quality study was to evaluate whether the 40-minute time target was achieved while fully addressing the clinical question.

Methods: CHD patients with indication for CMR were scanned on a 1.5T scanner. Ahead of the exam, patients were selected for a standard or accelerated protocol. Patients with a precisely defined clinical question (e.g., follow-up of size of aortic root or ventricular volumes, shunt quantification) and unlikely to require contrast agent were scheduled for accelerated CMR. The scan time was calculated based on the time of the first and last CMR sequence. The typical protocol for accelerated CMR included localizers, true fast imaging with steady-state free precession (TRUFI, SSFP), in axial, coronal and sagittal planes, long and short axis compressed-sensed cine SSFP, 3D self-navigated whole heart, native T1 mapping, 2D and 4D flow while for standard CMR, contrast-enhanced angiography, post-contrast T1 mapping and late gadolinium enhancement sequences were added. Patients were divided into groups of aorthopathy (i.e. bicuspid aortic valve, coarctation, Marfan syndrome), right-sided CHD, shunt lesions and other.

Results: Of 184 ambulatory patients, 113 underwent standard and 71 accelerated CMR. All clinically relevant questions were answered. In the accelerated group, the 40min scan time was met in 76% of cases with an overall mean scan time of 36min 22s (Figure). 12 patients needed contrast administration to improve image quality or for clinical reasons, prolonging mean scan time (39min 11s vs. 35min 47s without contrast; p=0.03, Table 1). Scan time was significantly longer in right-sided CHD than in aortopathy in the accelerated group (p = 0.037, Table 2). Scan time non-adherence in the accelerated group was associated with contrast use (35% vs. 11%, p=0.03).

Conclusion: Accelerated CMR is feasible in selected patients, while in most patients the planned scan time can be respected, allowing adequate response to the clinical question. Clinical need for contrast administration and right-sided CHD are associated with prolonged scan time.
Our results highlight the potential and feasibility of CMR acceleration. Continuous implementation of new accelerated imaging sequences will allow to further shorten scan time thus replying to the increasing demand of CMR in CHD patients.

Table 1: Comparison of patient characteristics between standard and accelerated group

	Standard group	Accelerated group	p
Age (median; IQR)	32.9 (32.9; 46.9)	26.1 (21.3; 36.0)	0.004
Sex, female (%)	46 (41)	28 (39)	0.879
Scan time (mean±SD)	55:40 ± 11:35)	36:22± 07:46)	< 0.001
Aortopathy, N (%)	35 (31)	43 (61)
Right sided CHD, N (%)	35 (31)	16 (23)
Shunt lesion, N (%)	29 (26)	9 (13)
Other, N (%)	14 (12)	3 (4)
Contrast, N (%)	92 (81)	12 (17)	< 0.001
Scan time respected N, (%)	81 (72)	53 (76)	0.609

Abbreviations: CHD=congenital heart disease, Nfnumber of patients, IQR=interquartile range, SD= standard deviation</span>

p-values were calculated with independent t-test for normally distributed parameters and with Man-Whitney-U test for not normally distributed parameters or Chi-square test for frequencies. Table 2: Comparison of mean scan time in each group (mean and SD)

Scan time (min, sec)	Standard group	Accelerated group	p
Aortopathy, mean±SD	51:35 ± 07:38	34:48 ± 06:28	< 0.001
Right sided CHD, mean±SD	57:47 ± 11:22	40:31 ± 07:04	< 0.001
Shunt lesion, mean±SD	57:33 ± 12:19	36:09 ± 05:37	< 0.001
Other, mean±SD	56:37 ± 12:01	37:02 ± 14:22	0.013

Abbreviations: see table 1Figure: Histograms of duration of standard and accelerated CMR exams