JACC. Cardiovascular imaging最新文献

Background: Despite extensive evidence of the beneficial effects of proprotein convertase subtilisin/kexin type 9 inhibition on clinical outcomes, the mechanisms for favorable outcomes remain poorly understood.

Objectives: The authors evaluated alterations in plaque morphology using intracoronary imaging and gene expression in peripheral blood mononuclear cells after adding evolocumab to maximum statin therapy.

Methods: A total of 110 stable coronary artery disease patients receiving maximally tolerated statin therapy were treated with evolocumab 140 mg every 2 weeks for 26 weeks. Serial optical coherence tomography, intravascular ultrasound, and near-infrared spectroscopy of nonobstructive lesions were performed in all patients at baseline and 26-week follow-up; peripheral blood mononuclear cells were isolated for bulk RNA transcriptomic sequencing. Machine learning models were used to predict baseline transcriptomic signatures of beneficial imaging response of plaque stabilization.

Results: After evolocumab treatment, optical coherence tomography-verified fibrous cap thickness (FCT) increased from 70.9 ± 21.7 to 97.7 ± 31.1 μm (mean 26.8 ± 22.3 μm; P < 0.001), and maximal lipid core burden index within 4 mm (LCBI) decreased from 306.8 ± 177.6 to 213.1 ± 168.0 (mean -93.7 ± 140.5; P < 0.001). In addition, there was a significant reduction in the percentage atheroma volume (-1.38% ± 1.48%; P < 0.001) defined by intravascular ultrasound. In total, 922 up-regulated and 571 down-regulated differentially expressed genes were identified at follow-up. Among 110 patients, 88 (80%) demonstrated FCT increase >0 (FCT responders), and 86 (78%) demonstrated LCBI reduction >0 (LCBI responders). Whereas multiple canonical pathways modulating immune cell adhesion, recruitment and communication were down-regulated, those associated with mitochondrial function, cell survival, and protein synthesis were significantly up-regulated in response to evolocumab. Elastic net models with 38 genes for FCT increase (AUC = 0.97) and 71 genes for LCBI reduction (AUC = 0.86) were able to predict patient response using baseline genes with high accuracy. The transcriptomic signature of beneficial response included pathways modulating inflammation, matrix metalloproteinases, neutrophil degranulation, and oxygen exchange.

Conclusions: In stable coronary artery disease, intravascular imaging-verified beneficial changes in plaque morphology after evolocumab treatment were associated with restored mitochondrial function, suppressed inflammation, and alleviated oxidative stress. Similar studies of plaque morphology with noninvasive modalities would allow the confirmation of novel pathways of plaque stabilization in response to maximized lipid-lowering therapy in larger number of subjects.

Epidemiological population studies may include cardiac magnetic resonance (CMR)-derived phenotyping and large-scale genotyping, providing unprecedented level of detail to investigate novel gene-lifestyle-disease interactions. The systematic review presents high-level summaries and critically appraises contemporary challenges and biobank opportunities. The authors identified 17 relevant biobanks by searching "CMR," "genome" and "population study" on MEDLINE, EMBASE, and Web of Science 2025. Collectively, studies recruited ∼1 million participants with stored blood samples for extensive genomic analyses, of whom >180,000 have or will undergo CMR. Use of expansive personal data must safeguard participant confidentiality, encourage technological standardization, and champion inclusivity and sustainability. Application of genotypic and imaging-derived phenotypic information will be readily translatable to clinical practice through investigation of, among others, new therapeutic targets and highly sensitive and specific biomarkers. Imaging biobanks are accessible to researchers by application. This systematic review should inspire greater use and cross-collaboration and facilitate powerful discoveries in more heterogeneous population samples.

Background: On-site computed tomography (CT)-derived fractional flow reserve (FFR) solutions are increasingly needed to reduce delays, costs, and reliance on external platforms.

Objectives: This single-center prospective study evaluated the diagnostic performance of an on-site deep learning and fluid dynamic-based CT-FFR algorithm (xFFR, GE HealthCare) against off-site HeartFlow CT-FFR (FFRct) and invasive FFR (iFFR) for coronary artery disease (CAD) assessment.

Methods: In this single-center prospective study, 250 symptomatic patients at intermediate-to-high CAD risk (mean age: 65 ± 9 years; 76% male) underwent coronary computed tomography angiography (CTA), xFFR, FFRct, and invasive coronary angiography with iFFR. Areas under the curve (AUCs) were calculated for xFFR and FFRct, with Spearman's correlations and Cohen's κ used to assess agreement with iFFR.

Results: Functionally significant CAD was detected in 56.6% (xFFR), 54% (FFRct), and 48% (iFFR) of cases; xFFR showed sensitivity, specificity, and accuracy of 95%, 81%, and 88%, respectively. The overall diagnostic accuracy was comparable to FFRct (AUC: 0.91 vs AUC: 0.89; P = 0.274), superior only for left anterior descending coronary artery assessment (AUC: 0.96 vs AUC: 0.84; P = 0.001). Correlation analysis showed good agreement with iFFR (ρ = 0.67) and FFRct (ρ = 0.53). The mean xFFR analysis time was 8 ± 3.4 minutes.

Conclusions: This study establishes xFFR as a robust and efficient on-site tool for assessing CAD, demonstrating high diagnostic accuracy, reproducibility, and agreement with invasive methods. Its rapid processing and integration into clinical workflows position xFFR as a promising alternative to off-site FFRct solutions. Further studies are warranted to confirm its generalizability and optimize its implementation.

Background: Cardiovascular disease prevention relies on accurate risk assessment; however, existing scores are imprecise. Routine imaging may be opportunistically used to predict risk.

Objectives: The authors tested whether computed tomography (CT)-derived cardiac and aortic structure predicts major adverse cardiac events (MACE) beyond standard-of-care scores.

Methods: The authors developed a least absolute shrinkage and selection operator model to predict cardiovascular mortality using "radiomics" features describing cardiac and aortic structure from 13,437 lung cancer screening CTs from the NLST (National Lung Screening Trial). They compared this score to the PREVENT (Predicting Risk of Cardiovascular Disease Events) tool and the coronary artery calcium (CAC) score in patients with routine chest CT and no prior MACE from Mass General Brigham. They calculated discrimination using Harrel's C-index and MACE rates in high-risk groups by the PREVENT score (≥7.5% risk) or the radiomics score (≥3.0% in men, ≥1.5% in women).

Results: In external testing, (n = 14,577, mean age 61.1 ± 8.6 years, 47.5% male), 6.2% had incident MACE over a median of 5.7 years of follow-up. The radiomics score had higher discrimination for MACE than PREVENT (C-index 0.66 [95% CI: 0.64-0.68] vs 0.61 [95% CI: 0.59-0.63]) and was complementary to CAC (combined C-index 0.69 [95% CI: 0.67-0.71] vs CAC alone 0.66 [95% CI: 0.65-0.68]). High-risk patients by the radiomics score but not PREVENT had 3.6-fold higher MACE incidence than low-risk patients by both scores (23.1 [95% CI: 16.7-30.2] vs 6.5 [95% CI: 5.5-7.5] MACE per 1,000 person-years). Aortic surface-to-volume ratio, left ventricular volume, and left atrial short-axis length were among the most predictive features of MACE.

Conclusions: CT-derived structural cardiac and aortic radiomics identified high-risk patients missed by clinical scores and further stratified risk among CAC risk groups. High-risk patients may benefit from intensified primary prevention.

Background: Recent guidelines suggest that coronary computed tomography angiography (CTA) may be the preferred testing modality in patients <65 years of age who are suspected of having coronary artery disease (CAD). Because of a higher prevalence of CAD, the role of coronary CTA in older cohorts is less well established.

Objectives: The authors aimed to characterize the yield and prognostic utility of coronary CTA by age in a large registry with long-term follow-up.

Methods: Retrospective cohort of patients clinically referred to coronary CTA at 2 medical centers from 2006 to 2021, excluding patients with prior CAD, severe renal disease, and malignancy. Adjusted Cox regression was used to assess the association of CAD severity (absent, nonobstructive, obstructive) and extent (number of vessels with plaque) with adverse cardiovascular events (major adverse cardiovascular events [MACE]: cardiovascular death, nonfatal myocardial infarction, or ischemic stroke) across different age groups.

Results: Among 22,412 patients followed over a median of 6.2 years (Q1-Q3: 3.9-9.6 years), 16,726 were <65 years of age and 5,686 were ≥65 years of age. Older patients had a higher prevalence of obstructive CAD (38% vs 15%) and extensive plaque (52% vs 20% with 3- to 4-vessel involvement) compared with their younger counterparts. Nonobstructive plaque was common in both groups (<65 years of age: 37%; ≥65 years of age: 48%). Obstructive CAD was associated with MACE in both younger (HR: 2.45; P < 0.001) and older individuals (HR: 1.97; P < 0.001). Nonobstructive plaque was associated with MACE in younger individuals (HR: 1.39; P = 0.005), whereas only extensive nonobstructive CAD was associated with MACE in older individuals (HR: 1.56; P = 0.02). Among those with obstructive CAD on coronary CTA who underwent early invasive coronary angiography, revascularization was less common among older adults (48% vs 56%; P = 0.002).

Conclusions: In a large coronary CTA registry, patients ≥65 years of age were more likely to have extensive plaque and stenosis. Although the prognostic value of coronary CTA may be lower among older adults with nonobstructive plaque (a group that has a similar event rate as those with no CAD), the presence of extensive nonobstructive plaque or obstructive stenosis was independently associated with a significantly higher rate of MACE. Newer techniques to better risk stratify patients with nonobstructive plaque may improve the value of coronary CTA, especially in older adults.

Background: The prognostic value of serial myocardial fibrosis assessments in hypertrophic cardiomyopathy (HCM) remains to be elucidated.

Objectives: The study aims to investigate late gadolinium enhancement (LGE) progression via follow-up cardiac magnetic resonance (CMR) in HCM patients and its prognostic value.

Methods: Retrospective analysis included 313 HCM patients with 2 CMR studies (between 2010 and 2019). LGE mass progression (ΔLGE mass/y) was defined as the increase in grams of enhanced myocardium divided by interval scan years. The primary endpoint included all-cause mortality, heart transplantation, aborted sudden cardiac death, unscheduled hospitalization for heart failure, and stroke. The secondary endpoint included all-cause mortality, aborted sudden cardiac death, and heart transplantation. Maximally selected rank statistical analysis was conducted to identify the optimal cutoff for ΔLGE mass/y.

Results: LGE mass progressed from a median of 2.9 g at the first CMR study to 8.3 g at the second CMR study (median scan interval 4.2 years). During a median follow-up period of 3.4 years after the second CMR study, 69 patients reached the primary endpoint, 17 of whom reached the secondary endpoint. For the primary and secondary endpoints, the optimal cutoffs for ΔLGE mass/y were >1.50 and 3.75 g/y, respectively. Multivariable Cox regression analysis showed that ΔLGE mass/y >1.50 g/year was an independent predictor of the primary endpoint (HR: 2.22 [95% CI: 1.13-4.34]; P = 0.02). The addition of ΔLGE mass/y to the baseline model improved the discrimination (C statistic = 0.81 vs 0.84) and risk reclassification (net reclassification improvement = 0.27, integrated discrimination improvement = 0.02; P < 0.001 for both). External validation in 6 multicenter data sets confirmed the prognostic value of ΔLGE mass/y.

Conclusions: In HCM patients, myocardial fibrosis increased over time. Serial assessments of myocardial fibrosis on CMR may improve risk stratification and clinical decision-making.