CT-based multi-threshold calcium scoring for aortic valve assessment: comparable predictive performance across HU thresholds in a pre-TAVI cohort.

Journal of Community Hospital Internal Medicine Perspectives Journal of Community Hospital Internal Medicine Perspectives

CT-derived AVA demonstrates strong agreement with TTE and provides complementary information for severity assessment and risk stratification in patients with aortic stenosis, particularly in cases with discordant or borderline findings.

Diagnostic performance of computed tomography-derived fractional flow reserve in patients with severe aortic stenosis undergoing transcatheter aortic valve implantation: a single-centre feasibility study.

OBJECTIVE Coronary artery disease (CAD) is prevalent in patients with severe aortic stenosis (AS) undergoing transcatheter aortic valve implantation (TAVI). Computed tomography-derived fractional flow reserve (CT-FFR) may provide non-invasive functional assessment using existing TAVI planning imaging to evaluate CT-FFR diagnostic performance compared with invasive coronary angiography (ICA) for identifying functionally significant CAD in TAVI candidates. METHODS This single-centre retrospective study included 37 patients with severe AS undergoing TAVI (June 2016-June 2023). All underwent pre-procedural coronary CT angiography and ICA. CT-FFR was retrospectively analysed using deep learning-based software (threshold < 0.81 for significant stenosis). Diagnostic performance was assessed per-vessel (52 coronary arteries) using ICA as reference standard. RESULTS Mean age was 79.2 ± 8.4 years; 56.7% were male. ICA identified significant CAD in 14 patients (37.8%), involving 21 lesions. CT-FFR successfully analysed all 52 vessels in the final cohort (mean value 0.86 ± 0.11) identifying 20 lesions (38.4%) as functionally significant; however, 8 of 62 initially screened patients (12.9%) were excluded due to insufficient CT image quality, reflecting a relevant limitation of clinical feasibility. CT-FFR demonstrated sensitivity 80.9% (95% CI: 58.1%-94.6%), specificity 93.5% (95% CI: 78.6%-99.2%), positive predictive value 85.0%, negative predictive value 90.6%, and diagnostic accuracy 88.5%. No significant difference existed between CT-FFR and ICA classifications (p > 0.05). At 30 days, no deaths, myocardial infarctions, or strokes occurred. CONCLUSION CT-FFR provides good diagnostic performance for detecting haemodynamically significant CAD in TAVI candidates. Integration into routine workflows may reduce purely diagnostic invasive procedures while maintaining accuracy. Larger prospective studies are needed to validate these findings.

Diagnostic Value of Calcium Score Derived From Virtual Noncontrast, Non-ECG-gated Dual-energy CT as an Indicator of Severe Aortic Stenosis.

Aortic Valve Calcium Score obtained on VNC images from DECT examinations is a promising method for noninvasively differentiation between severe and nonsevere aortic stenosis, which could be potentially useful in patients who have undergone examinations for noncardiac indications.

Quantitative coronary artery and aortic valve calcification by virtual non-contrast Images from dual-energy delayed CT scans in patients with severe aortic stenosis.

With the growing use of delayed dual-energy computed tomography (DECT) imaging for extracellular volume assessment, this study aimed to assess the accuracy of coronary artery calcium (CAC) and aortic valve calcification (AVC) quantification in virtual non-contrast (VNC) images derived from delayed DECT images. Eighty-eight patients undergoing pre-transcatheter aortic valve replacement (TAVR) cardiac CTA with DECT were retrospectively enrolled. We compared CAC score (CACS), CAC volume, AVC score (AVCS), and AVC volume between true non-contrast (TNC) and VNC images. VNC images were created by subtracting iodine from delayed CT angiography using commercial post-processing software. Concordance for the likelihood of severe aortic stenosis (AS) between TNC and VNC was assessed using guideline-based AVCS thresholds: men > 3,000 AU, women > 1,600 AU (highly likely); men > 2,000 AU, women > 1,200 AU (likely). CACS was lower in VNC than TNC (363.0 [13.7-1,154.0] AU vs. 470.1 [46.8-1,569.9] AU, p < 0.001), but the correlation was excellent (r = 0.966). No significant difference between VNC and TNC was observed in AVCS (959.5 [321.2-2,475.0] AU vs. 1,079.6 [492.2-2,329.4] AU, p = 0.521), with strong correlation (r = 0.966). Application of a correction factor (1.1-fold) improved agreement between VNC- and TNC-derived CACS (weighted κ = 0.839 to 0.869). Diagnostic concordance for severe AS between VNC and TNC was 92.1% (weighted kappa = 0.785) at the "highly likely" threshold and 97.7% (weighted kappa = 0.952) at the "likely" threshold. Delayed VNC images from DECT demonstrate strong agreement with TNC images for CACS and AVCS, suggesting that delayed VNC could potentially reduce the need for TNC acquisition in pre-TAVR assessment.

Coronary artery calcium and thoracic aortic calcification on non–ECG–gated chest CT in a large community-based cohort of Chinese men and women

Aims Non-ECG-gated chest CT frequently identifies coronary artery calcification (CAC) and thoracic aortic calcification (TAC), but age- and sex-specific thresholds remain unclear in Chinese communities. The ACC/AHA guideline recommends statins for those with CAC ≥75th percentile1. In subgroups with CAC positivity rate ≤25%, any detectable CAC corresponds to the ≥75th percentile. We aimed to determine precise sex-specific age thresholds using single-year stratification for opportunistic cardiovascular risk stratification. Methods A total of 42 363 participants aged 1–105 years (mean age: 56.9 ± 17.3 years; 52.0% male) who underwent non‑ECG‑gated chest CT from 2023 to 2025 were enrolled in this retrospective study. CAC and TAC were visually evaluated as binary (present/absent) variables. Single‑year stratification was applied to calculate key age thresholds corresponding to 25%, 50%, and 75% positivity rates of CAC and TAC. Distributions of isolated CAC, isolated TAC, and combined vascular calcification were compared between men and women. Results The ages at which CAC positivity reached 25%, 50%, and 75% were 48, 57, and 70 years for men versus 58, 67, and 76 years for women. Corresponding TAC threshold ages were 57, 60, and 71 years in men and 60, 67, and 78 years in women; TAC showed strong age dependence with modest sex‑related differences. The inflection age for CAC positivity exceeding 25% was approximately 58 years in women, around 10 years later than that observed in men. Isolated CAC was more frequent among men, while isolated TAC predominated in women; combined calcification became the dominant phenotype with increasing age. Conclusion In male aged <48 years and women aged <58 years, CAC detected on non-gated chest CT may warrant statin initiation, providing additional cost-free opportunistic risk stratification beyond current guideline recommendations. Moreover, CAC-negative individuals aged <70 years in men and <76 years in women are likely to have a favorable cardiovascular prognosis.

Diagnostic performance of CT-derived fractional flow reserve across coronary lesion morphologies: a prospective multicenter study.