RPS 1403 - Valves and pulmonary hypertension: the role of cardiac CT and MRI

Author Block: E. Moliterno, L. Giarletta, A. Pasquini, M. Massetti, L. Natale, R. Marano; Rome/IT
Purpose: To compare the size assessment of the mitral annulus (MA) obtained by preoperative CCT with the intraoperative 3D-TOE in patients undergoing surgical mitral valve repair (MVr) and assess their agreement with the MA measured intraoperatively by the surgeon.
Methods or Background: 55 patients with severe primary mitral regurgitation and candidates to MVr by the Carpentier technique with annuloplasty underwent pre-surgery CCT to exclude coronary artery disease (CAD). We compared CCT-derived MA sizing on short-axis view according to the D-shape MV segmentation model obtaining inter-trigonal distance, septal-to-lateral and inter-commissural distances, with those obtained by 3D-reconstruction of intra-operative TOE and the surgical implanted ring sizes, using intraclass correlation.
Results or Findings: Good agreement resulted between the inter-trigonal distance measured by CCT and the surgical ring (ICC 0.89 [CI 0.330-0.985; p < 0.05]) and between inter-commissural distance obtained by 3D-TOE and surgical ring (ICC 0.81 [CI 0.458-0.936; p < 0.05]), while the inter-trigonal distance measured by 3D-TOE showed a moderate agreement (ICC 0.63 [CI 0.056-0.852; p < 0.05]).
Excellent agreement resulted between the inter-trigonal distance assessed by intraoperative 3D-TOE and CCT (ICC 0.95 [CI 0.755-0.989; p<0.05]).
Conclusion: Our study shows the good accuracy of the pre-procedural CCT-based MA size assessment in comparison with the intraoperative 3D-TOE and the conventional surgical sizing, proposing CCT as a complementary non-invasive imaging technique in predicting eligibility and surgical ring sizing in patients candidate to MVr.
Limitations: The major study limitations are the relatively small sample size and the monocentric design.
Funding for this study: None
Has your study been approved by an ethics committee? Not applicable
Ethics committee - additional information: No additional information

Author Block: P. Marakhouskay, P. Chernoglaz, K. Marakhouski, K. Drozdovski; Minsk/BY
Purpose: The aim of the study was to quantify the method of planning transcatheter pulmonary valve implantation (TPVI) in patients who have undergone surgery for congenital heart defects(CHD) by measuring in both ECG and non-ECG gated CTA sizes of pulmonary artery(PA).
Methods or Background: 22 patients with CHD as Tetralogy of Fallot and Double outlet Right Ventricle(DORV), operated in infancy, were included into study and divided into two groups: study group, in which direct intravascular balloon sizing of PA was performed, and control group in which TPVI was rejected for excessive artery size without performing angiography.
CTA of all cases were retrospectively analyzed and 4 sizing zones were measured: RVOT, supravalvular zone, middle-segment of and bifurcation zone of PA. After that calculations to find appropriate patient -specific sizing methods by comparing parameters with an actual stent size were made (MedCalc Software Ltd, Ostend, Belgium; https://www.medcalc.org;2022).
Results or Findings: Analysis showed no significant correlation between diastolic RVOT sizing with any other measuring points or an actual stent size (P=0,0004). Only supravalvular zone was accepted as an independent residual in regression analysis (F-ratio 22, P=0,0004).
After implementing a regression equation to calculate appropriate size of PA stent on the control group, all the stents exceeded 30 mm (TPVI exclusion point). Mann-Whitney U-Test showed that the significant difference between an actual stent size and calculated size for study group (U 91,00,P = 0,5678) and no significant difference between calculated sizes of two groups (U 0,50 P = 0,0004).
Conclusion: Our study showed that any cardiac CT-based preTPVI landing zone sizing in diastolic phase can be based solely on measuring supravalvular zone of PA (r= 0,7992, F-ratio 22, P=0,0004), especially as an exclusion criteria (U 0,50 P = 0,0004).
Limitations: None
Funding for this study: No funding
Has your study been approved by an ethics committee? Yes
Ethics committee - additional information: Approved by the Ethics Committee of the NACPS No. 11 22.03.24.

Author Block: A. F. F. Tekin, B. Tütüncüoğlu, T. Banaz, Ö. Altun, Y. C. Kartal, S. Ozkök; Istanbul/TR
Purpose: Tetralogy of Fallot (TOF) is a congenital heart disease surgically repaired in early life.Guidelines recommend pulmonary valve replacement (PVR) for these patients. However, the effects of PVR on lung perfusion are not yet fully understood.In our study, we aimed to evaluate the changes in lung perfusion following PVR in patients with surgically corrected TOF.
Methods or Background: The study included 10 patients with surgically corrected TOF (M/F: 6/4, mean age: 16 years, median: 11-19 years).Lung perfusion was assessed using 4D time-resolved magnetic resonance angiography (MRA) before and 1 year after pulmonary valve replacement (PVR) .Gadolinium-based contrast was administered and images were analyzed with Philips Intellispace workstation.For measurement, ROI 's were manually placed in the main pulmonary artery before bifurcation, the aortic arch, upper, middle, and lower lobes of the right and left lungs.Changes in both ventricular parameters, pulmonary insufficiency ratio, and perfusion were assessed before and after PVR. Statistical analyses were performed using SPSS .Data were reported as medians and the Wilcoxon-sum rank test was used.
Results or Findings: Following PVR, a reduction in pulmonary regurgitation fraction and right ventricular end-diastolic volume was observed, while no changes were seen in right ventricular ejection fraction and left ventricular volume. After PVR, a difference was noted in right and left lung perfusion but no differences were observed between lung zones .
Conclusion: Lung perfusion assessment is a non-invasive, radiation-free imaging technique for the diagnosis and monitoring of various respiratory diseases.Improved pulmonary artery flow volumes, reduced perfusion heterogeneity, and enhanced perfusion dynamics following PVR reflect a positive impact on pulmonary hemodynamics.MRA-perfusion imaging can be a valuable tool for evaluating perfusion changes in this patient population.
Limitations: The planning of retrospective studies using a larger number of patient groups is necessary.
Funding for this study: No funding was received for this study.
Has your study been approved by an ethics committee? Yes
Ethics committee - additional information: This study was approved by Istanbul Medeniyet University Göztepe Training and Research Hospital Clinical Trials Ethics Commitee

Author Block: C. Gnasso, D. Vignale, A. Palmisano, S. Barbieri, E. Agricola, A. Esposito; Milan/IT
Purpose: Aortic stenosis (AS) causes myocardial microstructural modifications: the development of interstitial fibrosis, in particular, negatively impacts patients’ prognosis. Echocardiography, the gold standard for AS phenotypization, can’t investigate microstructural changes. CT -routinely performed for pre-procedural TAVI planning- can be implemented with delayed scans to assess myocardial fibrosis as ECV quantification. The prognostic role of ECV has already been demonstrated. The study aims to investigate the capacity of ECV to improve risk stratification on top of echocardiographic classification (low-flow low-gradient AS -LF-LG- vs high-gradient AS -HG-).
Methods or Background: Prospective, single-center study (IRCCS OSR Milan), enrolling consecutive patients undergoing CT for TAVI planning (Oct2020-Mar2023); clinical, echocardiographic, and laboratoristic data were collected. Patients were categorized as LF-LG or HG. The CT protocol included a low-dose delayed scan (5 mins after iodixanol 320 administration, 85-110 mL based on patient’s BMI). ECV was calculated with the formula: (1-hematocrit)x(ΔHUmyocardium/ΔHUblood), with ΔHU being the HU-difference in pre and post-contrast scans. The composite endpoint (death; heart failure hospitalization) was collected after a 1-year follow-up.
Results or Findings: The final cohort consisted of 415 patients (82 years [78-85]); 87 reached the endpoint. At Cox multivariable analysis including clinical, echo, and CT data, ECV (using the cut-off of 29% derived from Youden index) resulted an independent prognosticator of the endpoint, along with sex, hypercholesterolemia, diabetes and transvalvular gradient, with HR of 1.828 (95%CI1.151-2.903, p=0.0106), significantly higher in the LF-LG group (31.9(27.6-35.6) vs 28 (25.4;31), p<0.001). At Kaplan-Meier analysis, adding ECV to echo classification led to an improvement in risk stratification: HG-AS patients with higher ECV had a worse prognosis even compared to LF-LG-AS with low ECV (log-rank<.0001).
Conclusion: CT-ECV improves risk stratification in AS patients on top of echocardiographic evaluation.
Limitations: Lack of MR as reference standard
Funding for this study: None
Has your study been approved by an ethics committee? Not applicable
Ethics committee - additional information: All patients signed informed consent.
protocol number: CTMyoC 112/INT/2019

Author Block: C. Lisi¹, V. Mergen², L. J. Moser², K. Klambauer², H. Alkadhi², M. Eberhard²; ¹Milan/IT, ²Zurich/CH
Purpose: Diffuse myocardial fibrosis and altered deformation are relevant prognostic factors in aortic stenosis (AS) patients. The aim of this exploratory study was to investigate the relationship between myocardial strain, and myocardial extracellular volume (ECV) in patients with severe AS with photon-counting detector (PCD)-CT.
Methods or Background: We retrospectively included 77 patients with severe AS undergoing PCD-CT imaging for transcatheter aortic valve replacement (TAVR) planning between January 2022 and May 2024 with a protocol including a non-contrast cardiac scan, an ECG-gated helical coronary CT angiography (CCTA), and a cardiac late enhancement scan. Myocardial strain was assessed with feature tracking from CCTA and ECV was calculated from spectral cardiac late enhancement scans.
Results or Findings: Patients with cardiac amyloidosis (n=4) exhibited significantly higher median mid-myocardial ECV (48.2% versus 25.5%, p=0.048) but no significant differences in strain values (p>0.05). Patients with prior myocardial infarction (n=6) had reduced median global longitudinal strain values (-9.1% versus -21.7%, p<0.001) but no significant differences in global mid-myocardial ECV (p>0.05). Significant correlations were identified between global longitudinal, circumferential, and radial strains, and CT-derived left ventricular ejection fraction (EF) (all, p<0.001). Patients with low-flow, low-gradient AS and reduced EF exhibited lower median global longitudinal strain (GLS) values compared with those with high-gradient AS (-15.2% versus -25.8, p<0.001). In these patients, the baso-apical mid-myocardial ECV gradient correlated with GLS values (R=0.33, p<0.05).
Conclusion: In patients undergoing PCD-CT for TAVR planning, ECV and GLS may enable to detect patients with cardiac amyloidosis and patients with reduced myocardial contractility after myocardial infarction. Patients with low-flow, low-gradient AS and reduced EF showed lower median GLS correlating with basal LV fibrosis.
Limitations: Retrospective design, monocentric design, small sample number
Funding for this study: No funding
Has your study been approved by an ethics committee? Yes
Ethics committee - additional information: No additional information

Author Block: G. C. Pambianchi, G. Cundari, L. Marchitelli, C. Catalano, N. Galea; Rome/IT
Purpose: To evaluate functional and fluidodynamic modifications after MAP with different types of annuloplasty prosthetics using CMR 4D-flow techniques and left atrial (LA) strain feature-tracking
Methods or Background: We enrolled 12 patients treated with MAP (7 semi-flexible and 5 flexible incomplete rings), and had them undergo CMR at least 12 months after the procedure. The protocol included cineMR and 4D-Flow sequences with a whole heart coverage. We quantified TotalFlowVolume (TFV), PeakVelocity (Vmax), and WallShearStress (WSS) at LV inflow. We analyzed LA volumes and strain. MAP were compared with 30 age- and sex-matched healthy controls (10 studied with 4D-flow)
Results or Findings: MAP patients had lower EF (49.3±4.2% vs62.34±6.3%; p<0.021), reduced TFV (52.3±7.8ml vs69.6±9.7ml; p=0.039), and increased Vmax (159.7±21.3cm/s vs125.1±35.3 cm/s; p=0.002) compared to controls; the WSS resulted comparable between the groups (0.23±0.11 vs0.21±0.44; p=0.354). As for the flow patterns analysis, intraventricular and beneath the mitral valve flow, there was similar vortex formation among the two groups. MAP patients had decreased Reservoir (20.6±20.1% vs22.9±2.5%; p=0.033), lower Conduit (9.1±3.48% vs12.7±1.8%; p = 0.005), and increased Booster Pump strain (12.4±1.8% vs8.9±2.3%; p=0.001) compared to controls. The time between the surgery and CMR was inversely correlated with TVF (r: -0.95; p=0.04) but didn't affect the WSS.
Conclusion: Mitral annuloplasty with leaflets preservation did not considerably alter intraventricular flow patterns compared to healthy controls; while the prosthetic ring causes slight stenosis, WSS isn't significantly increased.
Atrial function was preserved in MAP but still reduced if compared to healthy controls.
Detailed evaluation of hemodynamic changes post-mitral repair and potential impact on the choice of annuloplasty devices and techniques to optimize long-term outcomes.
Limitations: The study had a numerically limited sample, patients didn't have pre-annuloplasty CMR,. We didn't analyze TKE and viscous energy loss.
Funding for this study: Not applicable
Has your study been approved by an ethics committee? Not applicable
Ethics committee - additional information: The study was submitted to local ethics committee

Author Block: G. Reiter, G. Kovacs, C. Reiter, H. Olschewski, M. Fuchsjäger, U. Reiter; Graz/AT
Purpose: Mean pulmonary arterial pressure (mPAP), pulmonary arterial wedge pressure (PAWP), and pulmonary vascular resistance (PVR) are the hemodynamic parameters measured during right heart catheterization (RHC) for diagnosis and classification of pulmonary hypertension (PH). This study aimed to assess the accuracy of 4D flow MRI in predicting these parameters non-invasively.
Methods or Background: 103 patients with known or suspected PH (PH/non-PH, 77/26) prospectively underwent both RHC and whole-heart 4D flow MRI at 3T. From 4D flow data, the duration of vortical blood flow along the main pulmonary artery (t_vortex), the left atrial acceleration factor (acc) and the cardiac output (CO_MR) were determined to derive estimates for mPAP via mPAP_MR = 16 + 0.63·t_vortex, PAWP via PAWP_MR = −6.2 + 10.1·acc, and PVR via PVR_MR = (mPAP_MR – PAWP_MR)/CO_MR. Relationships between invasive and 4D flow MRI-derived parameters were analyzed by correlation analysis and t-test. The performance of 4D flow MRI-derived parameters to predict the hemodynamic classification of PH was assessed by receiver operating characteristic curve analysis.
Results or Findings: The area under the curve (AUC) for predicting PH (mPAP > 20 mmHg) using mPAP_MR was 0.96. In PH patients, mPAP and mPAP_MR correlated strongly (r = 0.94) and showed no significant bias (0.6 ± 4.5 mmHg, p=0.24). Within PH patients, the AUCs for predicting post-capillary PH (PAWP > 15 mmHg) from PAWP_MR and PVR > 2 WU from PVR_MR were 1.00 and 0.95, respectively. PAWP and PAWP_MR correlated strongly (r = 0.94) and demonstrated no significant bias (0.4 ± 1.6 mmHg, p=0.05). PVR and PVR_MR correlated strongly (r = 0.85) but demonstrated a significant bias (0.8 ± 2.2 WU, p<0.01).
Conclusion: 4D flow MRI allows accurate non-invasive diagnosis and hemodynamic classification of PH.
Limitations: Single-center study
Funding for this study: None
Has your study been approved by an ethics committee? Yes
Ethics committee - additional information: Medical University of Graz, Austria

Author Block: C. Reiter, G. Reiter, G. Kovacs, D. Scherr, A. Schmidt, H. Olschewski, M. Fuchsjäger, U. Reiter; Graz/AT
Purpose: To assess the feasibility of measuring pulmonary arterial pulse wave velocity (PWV) – a potential prognostic marker in pulmonary hypertension (PH) – from 4D flow MRI.
Methods or Background: Thirty-one healthy subjects (15 females; age, 60 ± 10 years) and 10 patients with PH (6 females; age, 66 ± 11 years; mean pulmonary arterial pressure, 46 ± 11 mmHg) were prospectively recruited for 4D flow MRI at 3T. PWV was calculated using the transit-time approach (cvi42). Centerline segmentation of the pulmonary artery was performed twice, from the main pulmonary artery once to the left and once to the right pulmonary artery; PWV was measured in the main pulmonary artery as well as the entire segmented vessels. The pulmonary artery cross-section area was obtained from a multiplanar-reconstructed plane through the center of the main pulmonary artery. Results were analyzed using t-tests and correlation analysis.
Results or Findings: In healthy subjects, the main pulmonary arterial PWV was 2.4 ± 0.2 m/s with no significant difference between the main-to-right (2.7 ± 0.3 m/s) and main-to-left pulmonary PWV (2.7 ± 0.3 m/s, p=0.583). Moreover, no significant sex differences were observed (p=0.430). In PH subjects the PWV was higher than in controls in the main (6.1 ± 1.8 m/s, p<0.001), the main-to-right (7.7 ± 3.0 m/s, p<0.001) and the main-to-left pulmonary artery (7.1 ± 2.5 m/s, p<0.001). Main, main-to-right and main-to-left pulmonary artery PWV correlated significantly with the average pulmonary artery cross-section area (r = 0.78, 0.61 and 0.59, respectively; p<0.001 in all cases).
Conclusion: Pulmonary arterial PWV assessment from 4D flow MRI is feasible. Normal ranges align with values reported from 2D flow measurements, show small variations in healthy subjects, and differ compared PWV in patients with PH.
Limitations: Small sample size.
Funding for this study: OeNB Anniversary Fund 17934
Has your study been approved by an ethics committee? Yes
Ethics committee - additional information: Approval was obtained from the Ethics committee of the Medical University of Graz, Austria.