RPS 503 - Cardiac CT: plaques and beyond

Author Block: M. Y. Koopman¹, R. Willemsen², B. Kietselaer³, P. M. A. Van Ooijen¹, J-W. Gratama⁴, R. Braam⁴, R. Van Bruggen⁴, P. Van Der Harst⁵, R. Vliegenthart¹; ¹Groningen/NL, ²Maastricht/NL, ³Rochester, MN/US, ⁴Apeldoorn/NL, ⁵Utrecht/NL
Purpose: Computed Tomography coronary calcium scoring (CT-CCS) has higher sensitivity for detection of obstructive coronary artery disease (OCAD) than exercise electrography (x-ECG), but its utility as an initial diagnostic test in primary care remains unclear. This pilot study compares CT-CCS results with x-ECG results in primary care and assesses patients’ perspectives.
Methods or Background: Thirty-eight primary care offices participated in this study. After cluster randomisation, 19 offices referred patients with atypical angina pectoris or non-specific thoracic complaints for CT-CCS and 19 offices used x-ECG as the primary test (standard care). Clinical data were collected using electronic patient records, and patients’ perspectives on the diagnostic test were assessed through a questionnaire. Outcome measures included CAD diagnosis, initiation of cardiovascular risk management (CVRM), and patient satisfaction.
Results or Findings: In total, 101 patients were included. In 25 patients undergoing X-ECG, one (4%) had a positive test result and received CVRM, but no patients were diagnosed with obstructive CAD. CT-CCS was performed in 76 patients. 17 CT-CCS patients (23%) had a positive test result (calcium score >100), and 14 (19%) received CVRM. Obstructive CAD was diagnosed in four CT-CCS patients (5.3%). Of CT-CCS patients, 31 (43%) perceived the test as ‘very easy’ compared to none of the x-ECG patients.
Conclusion: CT-CCS is a promising diagnostic tool in primary care for the detection of obstructive CAD, offering a more patient-friendly experience compared to x-ECG.
Limitations: Small cohort, especially in the x-ECG arm, and low OCAD rate. A few patients received the test result before completing the questionnaire. Baseline cardiovascular related risk factors were inconsistently reported in electronic patient records.
Funding for this study: Funding was received from the Dutch Heart Foundation (Hartstichting, grant number: CVON2017-14).
Has your study been approved by an ethics committee? Yes
Ethics committee - additional information: The Medical Ethical Committee of the University Medical Center of Groningen approved CONCRETE (number 2018/404).

Author Block: F. Yavuz, F. Biavati, K. Schulze, S. Tsogias, B. Föllmer, A-M. Stantien, M. Bosserdt, M. Dewey; Berlin/DE
Purpose: To evaluate whether thin-slice non-contrast CT (NCCT) can detect prognostically relevant coronary plaques missed by conventional 3.0-mm reconstructions.
Methods or Background: This study included 141 patients from the CAD-Man trial [NCT00844220] (mean age 60.77 ± 11.06 years, 55% female) with available thin-slice NCCT (0.5-mm). The Agatston method was used to detect calcified plaques. Sensitivity and specificity for the detection of calcified plaques were calculated using CT angiography (CTA) as the reference standard. Lesion- and patient-level statistics were calculated for plaque volume parameters. Prognostic relevance was assessed by evaluating plaque progression rates for plaques detected only on thin-slice reconstructions, using median 10-year follow-up data when available.
Results or Findings: In total 551 calcified plaques were detected. Thin-slice NCCT showed a higher sensitivity (91.83%; 506/551) for detecting coronary calcified plaques compared to 3.0-mm reconstruction (82.76%; 456/551), although standard reconstructions showed an overall per-patient increased mean calcified plaque volume (197.22 mm3 ± 330.05 mm3) compared to thin-slice NCCT (162.65 mm3 ± 284.1 mm3). Conversely, we observed a slightly lower specificity (97.23%; 492/506) for thin-slice NCCT compared to standard reconstructions (99.56%; 454/456). Coronary calcified plaques missed in standard reconstructions were smaller in volume (2.67 mm3 ± 1.47 mm3) compared to all detected plaques (20.68 mm3 ± 25.56 mm3). Missing calcified plaques on standard reconstructions would have led to the omission of 9 out of 141 patients (6.4%). Additionally, plaques only identified on thin-slice NCCT at baseline were clearly visible at follow-up, with an average 7.9-fold increase in volume.
Conclusion: Coronary calcified plaques detected exclusively on thin-slice NCCT reconstructions showed increased plaque progression rates compared to plaques detected in conventional calcium scoring.
Limitations: This study involved patients from a single-centre, and 10-year follow-up data were not available for all patients with missed plaques.
Funding for this study: This study was funded by a grant of the Heisenberg programme.
Has your study been approved by an ethics committee? Yes
Ethics committee - additional information: The study was approved by ethics committee at Charité (EA1/124/23).

Author Block: S. Tsogias, B. Föllmer, M. Mohamed, F. Biavati, K. Schulze, M. Bosserdt, M. Dewey; Berlin/DE
Purpose: To investigate the association of segment-level coronary artery calcium (CAC) scoring derived features with major adverse cardiovascular events (MACE) compared to vessel-based and overall CAC scoring.
Methods or Background: This subanalysis of the multicentre DISCHARGE trial (NCT02400229) included a total of (N = 1446) patients (mean age 59.9 ± 10.2 years) who had received a calcium scoring CT and were followed up over a median timespan of 3.5 years. The definition of MACE included nonfatal stroke, nonfatal myocardial infarction and cardiovascular death. Associations with MACE were examined for proximal (LM and proximal segments of the LAD, LCX and RCA) versus non-proximal calcifications and the total number of segments containing calcifications out of 19 (0: No calcification; 1: Limited; 2-9: Moderate, ≥ 10: Extensive). CAC scores were obtained both manually and using deep learning-based scoring methods. Analysis was performed using Cox proportional hazards regression adjusting for age, sex, body-mass-index, diabetes, dyslipidemia, hypertension, family history, smoking status and Agatston categories (< 400; ≥ 400) with hazard ratios (HR) and 95% confidence intervals (CI).
Results or Findings: During follow-up a total of 31 MACE occurred. Proximal vessel calcifications were associated with higher risk for MACE (HR = 3.9, 95% CI [1.02, 14.5], p < .05). A moderate number of calcified segments [2-9 segments] was also associated with an increased risk for MACE (HR = 4.2, 95% CI [1.08, 16.1], p < .05).
Conclusion: Proximal vessel calcification as well as moderate segment calcification were associated with a higher risk for MACE.
Limitations: Due to the low number of MACE in this study population 2.1% (31 of 1446) the overall predictive value of the segment level CAC scoring may have been underrepresented.
Funding for this study: This work was funded by the German Research Foundation through the graduate program BIOQIC (GRK2260, project-ID: 289347353) and the DISCHARGE project (603266-2, HEALTH-2012.2.4.-2) funded by the FP7 Program of the European Commission.
Has your study been approved by an ethics committee? Yes
Ethics committee - additional information: The study was approved by The German Federal Office for Radiation Protection and the local or national authorities at each trial site.

Author Block: E. Bruno, A. Bettinelli, V. Morrone, A. Colombo, C. Gnasso, F. Pisu, D. Vignale, A. Palmisano, A. Esposito; Milan/IT
Purpose: Coronary artery disease (CAD) is a global leading cause of morbidity and mortality, with complex pathogenesis. Coronary computed tomography angiography (cCTA) is a powerful non-invasive tool for diagnosing obstructive CAD. However, most patients have non-obstructive CAD, and risk stratification data are limited. Many cCTA-based risk scores were developed, however with low predictive value and reproducibility.
This study aims to develop clinical-imaging models to predict major adverse cardiac events (MACEs) in patients undergoing cCTA for suspected CAD.
Methods or Background: Observational, single-center retrospective study including 4096 out of 10104 patients undergoing cCTA between 2016 and 2020. Patients with cardiovascular comorbidities or terminal cancer were excluded. Demographics, cardiovascular risk-factors, and medical history were collected via phone contact and medical records, to calculate known semiquantitative cCTA scores (CAD-RADS, Leiden risk score, Leaman risk score, SSS, SIS, Calcium score). Patients were compared after a minimum 4-year follow-up according to the occurrence of MACEs (cardiovascular death, nonfatal myocardial infarction, all-cause mortality, angina-related hospitalization, late coronary revascularization). Multivariable Cox regression models, adjusted for age and sex, were created using significant clinical variables and one cCTA score.
Results or Findings: Among 1933 patients enrolled (65% men, age:63.511.6 year-old), 353/1933(18%) had MACE. Patients with MACE had higher rates of hypertension, dyslipidemia, diabetes, and higher cCTA scores(all p<.001). All cCTA scores significantly predicted MACE occurrence in Kaplan-Meier survival analysis(p<.005). Six multivariable models including clinical features (diabetes, dyslipidemia, hypertension) and one cCTA score have been developed: in each model cCTA score was the strongest prognosticator of outcome, with CAD-RADS having the highest HR(2.996, 95%CI 2.374-3.781, p<.001), followed by CACS(2.103, 95%CI 1.646-2.687, p<.001).
Conclusion: CCTA scores area all predictors of outcome, in particular CAD-RADS, indicating the highest-grade coronary artery lesion, had the higher Hazard Ratio.
Limitations: No prospective data.
Funding for this study: None
Has your study been approved by an ethics committee? Yes
Ethics committee - additional information: Approved by San Raffaele hospital ethics committee (124/2023)

Author Block: B. Longere¹, R. Cusumano¹, C. V. Gkizas¹, A. Rodriguez Musso¹, F. Dubus¹, C. Croisille², C. Artaud¹, M. Haidar¹, F. A. Pontana¹; ¹Lille/FR, ²Bordeaux/FR
Purpose: To compare the image quality of myocardial delayed enhancement (CT-MDE) obtained by two different tube voltages and three distinct cardiac synchronization modes on a first-generation dual-source photon-counting detector CT (PCD-CT).
Methods or Background: Ninety patients (43 women) aged 63 years (54–73y) referred for cardiac CT with CT-MDE were enrolled. CT-MDE acquisition was performed 5min after injection of 90mL of iodine contrast medium (400mgI/mL). Tube voltage was set to either 120 or 140kVp. Current was automatically adjusted to a predetermined image quality level of 50. CT-MDE was acquired using helicoidal retrospective gating (R120; R140), sequential triggering (S120; S140) or prospective high-pitch gating (F120; F140). Triggering was set to an RR delay of 300ms. Signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR) and subjective image quality were assessed on virtual monoenergetic images at 65keV (VMI65) and iodine maps.
Results or Findings: High-pitch acquisitions provided the lowest CT dose index (P<0.001) with no differences in body mass index between the 6 groups (P=0.09). No differences were observed in SNR across the six acquisition types on VMI65 (P=0.07) and iodine map (P=0.22). F120 demonstrated a CNR that was equivalent to or better than that of the other acquisitions (VMI65, P=0.01; iodine map, P=0.04). No difference was observed in artifact scores (VMI65, P=0.43; iodine maps, P=0.83). Global subjective image quality provided by F120-derived VMI65 was better than or equivalent to that of other series (P=0.04).
Conclusion: High-pitch acquisition at 120kVp provides lower radiation dose without compromising image quality. This acquisition mode should be recommended for the assessment of CT-MDE with PCD-CT.
Limitations: It was a single-center study with a limited sample size. The detectability of iodine enhancement of pathological finding was not assessed as it was considered to be outside the scope of this study.
Funding for this study: None
Has your study been approved by an ethics committee? Yes
Ethics committee - additional information: IRB number: CRM-2408-417

Author Block: C. V. Gkizas¹, J. Limousin¹, W. Ben Mansoura¹, B. Longere¹, A. L. Rodriguez Musso¹, C. Croisille², F. A. Pontana¹; ¹Lille/FR, ²Bordeaux/FR
Purpose: The aim of this study was to assess the feasibility and accuracy of myocardial late enhancement (LE) scanning for extracellular volume (ECV) quantification with dual-source photon-counting detector computed tomography (PCD-CT) in acute myocarditis.
Methods or Background: Patients with clinical suspicion of myocarditis who were referred for coronary CT angiography (CCTA) to exclude CAD were included in this retrospective study. The CCTA protocol using a first-generation PCD-CT, included a systematic LE acquisition. ECV was calculated from the iodine ratio of the myocardium and blood pool on the LE scan. A comprehensive CMR protocol was used as the reference method to confirm myocarditis according to the Lake Louise 2018 criteria. All subjects underwent CCTA and CMR within 24 hours.
Results or Findings: 32 patients were included (mean age 36 years; 13 females). The mean dose length product of the LE scan was 96± 32 mGy.cm. The mean global ECV between CCT and CMR did not show significant difference (29.4% ±4.5 vs 30.0 ±4.1, P=0.69). In patients diagnosed with myocarditis confirmed by CMR (n=25), the mean ECV-CT was notably elevated compared to individuals with normal CCT and CMR findings (31.6% ±3.6 vs 25.6% ±3.2, P<0.01). ECV-CT value showed a strong positive correlation with LGE mass (r =0.85; p < 0.001).
Conclusion: Calculation of ECV using iodine maps derived from LE cardiac CT images is both feasible and accurate at low radiation dose. PCD-CT offers a promising non-invasive imaging method in the context of acute myocarditis.
Limitations: Retrospective, single study
Funding for this study: None
Has your study been approved by an ethics committee? Not applicable
Ethics committee - additional information: All subjects were informed and provided their consent.