||M Kawakubo, M Nagao, U Ishizaki, Y Shina, K Inai, Y Yamasaki, M Yoneyama, S Sakai., Feature-Tracking MRI Fractal Analysis of Right Ventricular Remodeling in Adults with Congenitally Corrected Transposition of the Great Arteries, Radiology: Cardiothoracic Imaging, 10.1148/ryct.2019190026, 1, 4, 2019.10,
To assess a recently available technique for quantification of right ventricular (RV) trabeculae that is based on fractal analysis performed by using cardiac MRI feature tracking, in patients with congenitally corrected transposition of the great arteries (cc-TGA).
Materials and Methods
A total of 19 patients (eight men, 11 women; mean age, 35 years ± 10 [standard deviation]) with consecutive cc-TGA who underwent cardiac MRI were enrolled in the study. For analysis, patients were divided into two groups: six patients (four men, two women; mean age, 34 years ± 14) with an end-systolic RV volume index higher than 72 mL/m2 (indicative of adverse RV remodeling) and 13 patients (four men, nine women; mean age, 36 years ± 9) in whom this index was lower than or equal to 72 mL/m2 (indicative of adapted RV). The following outcomes were quantified in the midsection of the RV: fractional fractal dimension (FD) and diastolic FD, circumferential strain, and radial strain. Receiver operating characteristic (ROC) analysis was performed to determine the cutoff FD values for the detection of adverse RV remodeling. Correlations among fractional FD, diastolic FD, circumferential strain, and radial strain were calculated by using Pearson correlation coefficient (r) analysis.
The following ROC values were identified for fractional and diastolic FD: cutoff, 0.09 and 1.39, respectively; area under the ROC curve, 0.95 and 0.68, respectively; sensitivity, 1.00 and 0.33, respectively; and specificity, 0.92 and 1.00, respectively. Fractional FD correlated with circumferential strain and radial strain (r = −0.70 and 0.69, respectively; P < .01), as did diastolic FD (r = 0.37 and −0.38, respectively; P < .05).
The fractional FD derived from cardiac MRI feature-tracking analysis correlates with adverse RV remodeling, including a changed strain pattern and trabeculae, in patients with cc-TGA..
||Shiina Y, Taniguchi K, Nagao M, Takahashi T, Niwa K, Kawakubo M, and Inai K., The relationship between extracellular volume fraction in symptomatic adults with tetralogy of Fallot and adverse cardiac events., Journal of Cardiology, DOI: 10.1016/j.jjcc.2019.09.009., 2019.10.
||Arai H, Kawakubo M*, Abe K, Hatashima H, Sanui K, Nishimura H, and Kadokami T. *Corresponding author, Quantification of intramyocardial hemorrhage volume using magnetic resonance imaging with three-dimensional T1-weighted sequence in patients with ischemia-reperfusion injury—a semi-automated image processing technique, The International Journal of Cardiovascular Imaging, In Press, 2019.09.
||R Nakao, M Nagao, K Fukushima, A Sakai, E Watanabe, M Kawakubo, S Sakai, N Hagiwara., Prediction of Cardiac Resynchronization Therapy Response in Dilated Cardiomyopathy Using Vortex Flow Mapping on Cine Magnetic Resonance Imaging, Circulation Reports, In Press, 2019.07.
||Kawakubo M*, Yamasaki Y, Kamitani T, Sagiyama K, Matsuura Y, Hino T, Abe K, Hosokawa K, Yabuuchi H, and Honda H. *Corresponding author, Clinical usefulness of right ventricular 3D area strain in the assessment of treatment effects of balloon pulmonary angioplasty in chronic thromboembolic pulmonary hypertension: comparison with 2D feature-tracking MRI, European Radiology, https://doi.org/10.1007/s00330-019-6008-3, 29, 9, 4583-4592, 2019.09,
To evaluate the usefulness of right ventricular (RV) area strain analysis via cardiac MRI (CMRI) as a tool for assessing the treatment effects of balloon pulmonary angioplasty (BPA) in inoperable chronic thromboembolic pulmonary hypertension (CTEPH), RV area strain was compared to two-dimensional (2D) strain with feature-tracking MRI (FTMRI) before and after BPA.
We retrospectively analyzed 21 CTEPH patients who underwent BPA. End-systolic global area strain (GAS), longitudinal strain (LS), circumferential strain (CS), and radial strain (RS) were measured before and after BPA. Changes in GAS and RV ejection fraction (RVEF) values after BPA were defined as ΔGAS and ΔRVEF. Receiver operating characteristic (ROC) analyses were performed to determine the optimal cutoff of the strain at after BPA for detection of improved patients with decreased mean pulmonary artery pressure (mPAP) less than 30 mmHg and increased RVEF more than 50%.
ROC analysis revealed the optimal cutoffs of strains (GAS, LS, CS, and RS) for identifying improved patients with mPAP < 30 mmHg (cutoff (%) = - 41.2, - 13.8, - 16.7, and 14.4: area under the curve, 0.75, 0.56, 0.65, and 0.75) and patients with RVEF > 50% (cutoff (%) = - 37.2, - 29.5, - 2.9, and 14.4: area under the curve, 0.81, 0.60, 0.56, and 0.56).
Area strain analysis via CMRI may be a more useful tool for assessing the treatment effects of BPA in patients with CTEPH than 2D strains with FTMRI..
||Arai H, Kawakubo M, Sanui K, Nishimura H, Kadokami T., Accurate and robust systolic myocardial T1 mapping using saturation recovery with individualized delay time: Comparison with diastolic T1 mapping, Radiol Phys Technol., https://doi.org/10.1007/s12194-018-0478-x, 11, 4, 415-422, 2018.09.
||Kawakubo M*, Arai H, Nagao M, Yamasaki Y, Sanui K, Nishimura H, Kadokami T. *Corresponding author, Global left ventricular area strain using standard two-dimensional cine MR imaging with inter-slice interpolation, Cardiovascular Imaging: Asia, https://doi.org/10.22468/cvia.2018.00108, 2, 4, 187-193, 2018.10.
||Kojima T, Kawakubo M, Nishizaka MK, Rahmawati A, Ando S, Chishaki SA, Nakamura Y, Nagao M, Assessment by airway ellipticity on cine-MRI to differentiate severe obstructive sleep apnea., Clinical Respiratory Journal, 10.1111/crj.12598., 12, 3, 878-884, 2018.03.
||Kawakubo M*, Akamine H, Yamasaki Y, Takemura A, Abe K, Hosokawa K, Morishita J, Nagao M. *Corresponding author, Three-dimensional phase contrast magnetic resonance imaging validated to assess pulmonary artery flow in patients with chronic thromboembolic pulmonary hypertension., Radiological Physics and Technologies, 2016.10.
||Kawakubo M*, Nagao M, Kumazawa S, Yamasaki Y, Chishaki AS, Nakamura Y, Honda H, Morishita J. *Corresponding author, Evaluation of ventricular dysfunction using semi-automatic longitudinal strain analysis of four-chamber cine MR imaging., The International Journal of Cardiovascular Imaging., 32, 2, 283-9, 2016.02.
||Kawakubo M*, Yamasaki Y, Sakamoto I, Yamamura K, Nagao M. *Corresponding author, Clinical Impact of Interventricular Dyssynchrony in Repaired Tetralogy of Fallot: Myocardial Strain Analysis Using Semi-automatic Tracking of Cine Magnetic Resonance Imaging., Journal of Adult Congenital Heart Disease, Vol. 4, No. 2, 69-73, 2015.12.
||Kawakubo M*, Nagao M, Kumazawa S, Chishaki AS, Mukai Y, Nakamura Y, Honda H, Morishita J. *Corresponding author, Evaluation of cardiac dyssynchrony with longitudinal strain analysis in 4-chamber cine MR imaging., European Journal of Radiology, 82, 12, 2212-2216, 2013.12.