Evaluation of Gadopiclenol Washout Kinetics and Optimal Timing for Late Gadolinium Enhancement Imaging

Presenting Author(s)

• MH

  Mehdi Hedjazi Moghari, PhD

  Associate Professor
  West Virginia University
  -, West Virginia, United States

Primary Author(s)

• EO

  Efeturi M. Okorigba, MD

  Internal Medicine Resident
  West Virginia University
  Morgantown, West Virginia, United States

Co-Author(s)

• AM

  Avilash Mondal, MD

  Advanced Cardiac Imaging Fellow
  West Virginia University, West Virginia, United States
• AJ

  Ayesha Tamkinat Jalal, MD

  Advanced Cardiac Imaging Fellow
  West Virginia University, United States
• MH

  Mobeen Z. Haider, MD

  Cardiology Fellow
  West Virginia University, West Virginia, United States
• SP

  Shauna Poindexter, RT

  MRI Modality Specialist
  West Virginia University
  Morgantown, West Virginia, United States
• MH

  Mina Hanna, MD, MSc

  Associate Professor, Section Chief
  West Virginia University, West Virginia, United States
• RH

  Ruby Havistin, MD

  Advanced Cardiac Imaging Fellow
  West Virginia University
  Morgantown, West Virginia, United States
• IZ

  Irfan Zeb, MD

  Cardiologist
  West Virginia University
  Morgantown, West Virginia, United States
• SB

  Sudharshan Balla, MD

  Associate Professor of Cardiology
  West Virginia University, United States
• MH

  Mehdi Hedjazi Moghari, PhD

  Associate Professor
  West Virginia University
  -, West Virginia, United States
• LM

  Lakshmi Muthukumar, Dr, MD, FSCMR

  Assistant Professor
  West Virginia University, West Virginia, United States

Background: Optimal timing of post-contrast imaging for late gadolinium enhancement (LGE) in cardiac MRI is essential for accurately detecting myocardial lesions, ensuring adequate lesion-to-myocardium contrast while minimizing the effects of contrast washout. Gadopiclenol (Vueway), a newly FDA-approved contrast agent, has limited published data regarding its washout kinetics and ideal timing for LGE imaging. This study aimed to characterize the washout rate of Gadopiclenol and identify the optimal delay time for LGE acquisition.

Methods: Fifty-five patients referred for contrast-enhanced cardiovascular magnetic resonance (CMR) at our institution were prospectively recruited. The CMR protocol included a segmented TrueFISP sequence (TI scout) to determine optimal myocardial nulling time, followed by single-shot phase-sensitive inversion recovery (PSIR) with TrueFISP readout and 8 signal averages for LGE imaging. TI scout images were acquired at two time points for each patient, and the difference in inversion times was used to calculate the washout rate in the myocardium and left ventricular cavity blood pool (BP), stratified by ejection fraction (EF).

In 17 patients, short-axis PSIR LGE images were acquired at 3- and 8-minute post-contrast (Gadopiclenol, 0.125 mL/kg), including 6 patients with myocardial scar. Regions of interest were placed in enhanced myocardium (EM), normal myocardium (NM), Blood pool (BP), and air at identical locations on corresponding images. Signal intensity, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) were measured at both time points. SNR and CNR comparisons were used to determine the optimal post-contrast acquisition time for PSIR LGE. Continuous variables were analyzed using a two-tailed t-test (p-value < 0.05 was considered statistically significant).

Results: In the washout rate group, the median age was 51 (37 – 66), and 53% were females. Similarly, in the LGE group, the median age was 52 (40 – 68), and 41% were females. Figure 1 shows an example of LGE images in short axis at 3- and 8-minute post-contrast. Tables 1 and 2 provides statistical comparisons. The washout rate was observed to be 0.18 milliseconds/second in the myocardium vs 0.14 milliseconds/second in the BP. The SNR of EM and BP was higher at 3 minutes vs 8 minutes (14.15 vs 9.0; p = 0.015) and (12.64 vs 9.51; p = 0.003), respectively. Similarly, the CNR (EM-NM) was better at 3 minutes (11.93 vs 6.59; p = 0.001), and the CNR (BP-NM) was also superior at 3 minutes (10.89 vs 8.20; p = 0.001).

Conclusion: In patients receiving Gadopiclenol, myocardial washout occurs faster than in BP. CNR between enhanced and normal myocardium (EM–NM) and between normal myocardium and BP (BP–NM) was higher at 3 minutes than at 8 minutes post-contrast. These findings suggest that acquiring cardiac PSIR LGE images at 3 minutes post-injection may optimize image quality and diagnostic accuracy. Future studies should include more patients with myocardial enhancement to compare CNR between EM and BP.

Table 1. Gadopiclenol Washout Rate

	Participants, n = 55(%)	Normal Ejection Fraction (EF > 50%) n =42 (%)	Low Ejection Fraction (EF < 50%) n =13 (%)
Age in years (median, IQR)p-value (Normal vs low EF)	51 (37 – 66)	51(33 – 62)	65 (51 – 69)
		0.007
Sex Female Male	29 (53)26 (47)	25 (60) 17 (40)	4 (31)9 (69)
Race White Black Other	52 (94)2 (4)1 (2)	41 (98)0 (0)1 (2)	11(82)2 (18)0 (0)
Haemoglobin (median, IQR)p-value (Normal vs low EF)	13.85 (12.58 – 14.8)	13.50 (12.40 – 14.63)	14.75 (13.78 – 15.15)
		0.090
BMI (median, IQR)p-value (Normal vs low EF)	29.10 (26.06 – 33.13)	29.47 (26.18 – 33.34)	28.51 (22.81 – 30.27)
		0.360
eGFRp-value (Normal vs low EF)	90 (77.8 – 90.00)	90 (78.75 – 90.00)	86.5 (61.75 – 90.00)
		0.180
Heart Rate (median, IQR)p-value (Normal vs low EF)	67 (60 – 74)	66 (60 – 72)	69 (62 – 80)
		0.300
Ejection Fraction (Median, IQR)p-value (Normal vs low EF)	57 (50 – 63)	61 (56 – 65)	42 (40 – 47)
		0.001
Dose of Gadopiclenol in mLs (median, IQR)p-value (Normal vs low EF)	10 (8.5 – 12.0)	10 (9 – 12)	10 (7 – 12)
		0.910
Washout rate (ms/sec) Myocardium (median, IQR) BP (median, IQR) p-value (Myo vs BP) Washout rate (ms/sec) stratified by Ejection fraction (EF) Myocardium (median, IQR) p-value (Normal vs low EF) BP (median, IQR) p-value (Normal vs low EF)	0.18 (0.14 – 0.24)0.14 (0.12 – 0.20)0.001	0.19 (0.14 - 0.25)0.14 (0.12 – 0.20)	0.15 (0.14 – 0.91)0.4900.14 (0.13 -0.16)0.840

Comparison of myocardial and Blood pool (BP) washout rates in all participants and stratified by ejection fraction (EF). IQR = interquartile range (25th–75th percentile) reported for skewed distributions. Washout was significantly faster in the myocardium compared to the BP (0.18 ms/s vs 0.14 ms/s; p-value = 0.001). No significant differences were observed between low and normal EF groups for either myocardial or BP washout, likely reflecting the limited sample size 
Table 2. Gadopiclenol SNR and CNR

	Participants,n = 17 (%)	Normal Ejection Fraction (EF >50%)n = 12 (%)	Low Ejection Fraction (EF < 50%)n =5 (%)
Age in years (median, IQR)  p-value (Normal vs low EF)	52 (40 – 68)	51 (40 – 68)	66 (53 – 66)
		0.210
Sex Female Male	7 (41)10 (59)	6 (50)6 (50)	1 (20)4 (80)
Race White Black Other	17 (100)0 (0)0 (0)	12 (100)0 (0)0 (0)	5 (100)0 (0)0 (0)
Haemoglobin (median, IQR)p-value (Normal vs low EF)	14.10 (11.55 – 14.65)	13.20(11.55 – 14.30)	14.80 (13.25 – 14.95)
		0.840
eGFR (median, IQR)p-value (Normal vs low EF)	90 (78.50 – 90.00)	90 (78.50 – 90.00)	90 (78.50 – 90.00)
		0.620
BMI (median, IQR)p-value (Normal vs low EF)	27.96 (26.17 – 30.27)	28.18 (26.58 – 33.46)	27.96 (23.63 – 28.51)
		0.170
Heart Rate (median, IQR) p-value (Normal vs low EF)	63 (57 – 68)	65 (60 – 71)	59 (55 – 63)
		0.190
Ejection Fraction (median, IQR)p-value (Normal vs low EF)	57 (48 – 61)	59 (57 – 66)	41 (39 – 44)
		0.005
Dose of Gadopiclenol in mLs (median, IQR)p-value (Normal vs low EF)	10 (9 – 11)	10.25 (9.45 – 11.13)	9.0 (8.7 – 9.6)
		0.310
Signal-to-Noise ratio
Enhanced Myocardium (EM) 3 minutes (median, IQR) 8 minutes (median, IQR) p-value (3 min vs. 8 min)	14.15 (11.92 – 16.12)9.0 (7.24 – 11.07)0.015	16.64 (15.06 – 18.21)12.71(11.72 – 13.69)0.190	13.10 (9.87 – 15.25)7.25 (6.57 – 8.26)0.080
Normal Myocardium (NM) 3 minutes (median, IQR) 8 minutes (median, IQR) p-value (3 min vs. 8 min)	1.23 (0.89 – 2.17)1.23 (0.85 – 2.00)0.316	1.62 (0.98 -2.42)1.45 (0.94 – 2.03)0.180	1.07 (0.79 – 2.09)0.99 (0.85 – 1.30)0.770
Blood pool (BP) 3 minutes (median, IQR) 8 minutes (median, IQR) p-value (3 min vs. 8 min)	12.64 (6.90 – 16.949:51 (6.54 – 14.67)0.003	12.74 (7.41 – 17.78)11.05 (7.75 – 16.90)0.016	12.64 (6.41 – 15.26)6.54 (6.02 – 9.20)0.130
Contrast-to-Noise ratio
EM-NM 3 minutes (median, IQR) 8 minutes (median, IQR) p-value (3 min vs. 8 min)	11.93 (9.41 – 14.28)6.59 (4.44 – 9.46)0.001	12.83 (11.47 – 14.20)10.05 (8.65 – 11.44)0.010	11.46 (8.01 – 13.92)4.93 (3.89 – 6.99)0.060
BP-NM 3 minutes (median, IQR) 8 minutes (median, IQR) p-value (3 min vs. 8 min)	10.89 (6.45 – 14.72)8.20 (5.24 – 12.30)0.001	10.86 (6.54 – 15.73)10.02 (6.67 – 15.15)0.030	11.56 (5.75 – 13.17)5.24 (5.18 – 8.20)0.080

Comparison of SNR and CNR at 3- and 8-minutes post-contrast, as well as between participants with normal and reduced ejection fraction (EF). IQR indicates the interquartile range (25th–75th percentile) for skewed distributions. SNR was significantly higher at 3 minutes in both the enhanced myocardium (EM) and Blood pool (BP). Similarly, CNR between EM and normal myocardium (NM), as well as between Blood pool and normal myocardium, was superior at 3 minutes.. However, no statistically significant differences was observed in the Normal vs reduced EF group, likely reflecting the limited sample size.Fig 1. Example of late gadolinium enhancement (LGE) magnitude (MAG) and phase-sensitive inversion recovery (PSIR) short-axis images at 3- and 8-minutes post-contrast in a 66-year-old male with Ischemic cardiomyopathy. Regions of interest include enhanced myocardium (EM), normal myocardium (NM), the left ventricular cavity (BP) and Microvascular obstruction (MVO) . Signal intensity, SNR, and CNR of the enhanced myocardium (EM) are higher at 3 minutes compared to 8 minutes.