Circulation: Cardiovascular Imaging最新文献

Background: Fluorine-18 fluorodeoxyglucose (FDG) with positron emission tomography (PET) is the standard for detecting myocardial inflammation in cardiac sarcoidosis, requiring preparation with the ketogenic diet (KD) to achieve myocardial glucose suppression. Despite this, incomplete myocardial glucose suppression remains a significant issue, and strategies to reduce myocardial glucose uptake (MGU) and identify incomplete myocardial glucose suppression are required. This study sought to understand the relationship between point-of-care beta-hydroxybutyrate (BHB) and different patterns of MGU and between KD and fasting duration with MGU in patients undergoing evaluation for cardiac sarcoidosis.

Methods: We prospectively included 471 outpatients who underwent FDG-PET for cardiac sarcoidosis evaluation, followed the KD for 1 (n=100), 2 (n=29), and ≥3 days (n=342), fasted for at least 12 hours, and had BHB levels measured immediately before FDG injection. Images were classified as (1) no MGU (negative), (2) focal/multifocal (positive), (3) diffuse (nondiagnostic), or (4) nonspecific uptake (NS-MGU).

Results: Cardiac FDG-PET scans were interpreted as the following: 376 (79.83%) negative; 61 (12.95%) positive; 14 (2.97%) diffuse; and 20 (4.25%) NS-MGU. There was a strong negative relationship between BHB levels and MGU (P<0.0001). BHB levels increased significantly with KD duration (P<0.0001) and fasting time (P=0.0067). The combined rate of diffuse, NS-MGU, and positive scans (34%, 28%, 16%) decreased inversely with KD duration (1, 2, and ≥3 days, respectively). However, MGU was not different across different fasting times (P=0.6). Blood glucose levels were not associated with MGU (P=0.17) and only weakly associated with BHB levels (R²=0.03; P<0.001).

Conclusions: We observed a strong inverse relationship between ketosis and patterns of MGU. Longer KD and fasting durations are associated with higher ketosis. However, only KD duration was associated with lower rates of MGU. Measurement of BHB levels before FDG-PET using point-of-care testing is feasible and may facilitate the management of patients referred for myocardial inflammation.

Background: Coronary computed tomography angiography provides valuable information for evaluating the difficulty of chronic total occlusion (CTO) percutaneous coronary intervention. This study aimed to investigate the value of CTO plaque characteristics derived from radiomics analysis for predicting the difficulty of percutaneous coronary intervention.

Methods: Patients with CTO were retrospectively enrolled from a hospital as training and internal test sets and from the other 2 territory hospitals as external test sets. Radiomics characteristics were extracted from the CTO segment on coronary computed tomography angiography. Radiomics and combined models were developed to predict successful guidewire crossing within 30 minutes (guidewire success) of CTO percutaneous coronary intervention. Subgroup analysis was conducted to investigate the influence of potential risk factors on the radiomics model performance.

Results: A total of 551 patients (median, 60; interquartile range, 52.00-66.00 years, 460 men) with 565 CTO lesions were finally enrolled. In the training, internal test, and external test sets, 203 of 357, 85 of 149, and 38 of 59 CTO lesions achieved guidewire success, respectively. Six radiomics features were selected for constructing the radiomics model. In the external test set, the area under the receiver operating characteristic curve of the radiomics model was significantly higher than prior prediction models (P<0.05 for all) with the area under the receiver operating characteristic curve, accuracy, sensitivity, and specificity of 0.86, 74.58%, 81.58%, and 61.90%, respectively. The performance of the radiomics model was dependent on calcification, CTO location, adjacent branch(es), and operator caseload.

Conclusions: CTO characteristics revealed by radiomics analysis can be used as effective imaging biomarkers for predicting guidewire success. However, the performance of the radiomics model depends on anatomic and operator factors.

Background: Right ventricular (RV) dysfunction is known to impact prognosis, but its determinants in coronary artery disease are poorly understood. Stress cardiac magnetic resonance (CMR) has been used to assess ischemia and infarction in relation to the left ventricle (LV); the impact of myocardial tissue properties on RV function is unknown.

Methods: Vasodilator stress CMR was performed in patients with known coronary artery disease at 7 sites between May 2005 and October 2018. Myocardial infarction was identified on late gadolinium enhancement-CMR, and infarct transmurality was graded on a per-segment basis. Ischemia was assessed on stress CMR based on first-pass perfusion and localized by using segment partitions corresponding to cine and late gadolinium enhancement analyses. RV function was evaluated by CMR-feature tracking for primary analysis with a global longitudinal strain threshold of 20% used to define impaired RV strain (RV_IS); secondary functional analysis via RV ejection fraction was also performed.

Results: A total of 2604 patients were studied, among whom RV_IS was present in 461 patients (18%). The presence and magnitude of RV_IS were strongly associated with LV dysfunction, irrespective of whether measured by LV ejection fraction or wall motion score (P<0.001 for all). Regarding tissue substrate, regions of ischemic and dysfunctional myocardium (ie, hibernating myocardium) and infarct size were each independently associated with RV_IS (both P<0.001). During follow-up (median, 4.62 [interquartile range, 2.15-7.67] years), 555 deaths (21%) occurred. Kaplan-Meier analysis for patients stratified by presence and magnitude of RV dysfunction by global longitudinal strain and RV ejection fraction each demonstrated strong prognostic utility for all-cause mortality (P<0.001). RV_IS conferred increased mortality risk (hazard ratio, 1.35 [95% CI, 1.11-1.66]; P=0.003) even after controlling for LV function, infarction, and ischemia.

Conclusions: RV_IS in patients with known coronary artery disease is associated with potentially reversible LV processes, including LV functional impairment due to ischemic and predominantly viable myocardium, which confers increased mortality risk independent of LV function and tissue substrate.

Recent studies have demonstrated that coronary plaque burden carries greater prognostic value in predicting adverse atherosclerotic cardiovascular disease outcomes than myocardial ischemia, thereby challenging the existing paradigm. Advances in plaque quantification through both noncontrast and contrast-enhanced computed tomography (CT) methods have led to earlier and more cost-effective detection of coronary disease compared with traditional stress testing. The 2 principal techniques of noninvasive coronary plaque quantification assessment are coronary artery calcium scoring by noncontrast CT and coronary CT angiography, both of which correlate with disease burden on invasive angiography. Plaque quantification from these imaging modalities has shown utility in risk stratification and prognostication of adverse cardiovascular events, leading to increased incorporation into clinical practice guidelines and preventive care pathways. Furthermore, due to their expanding clinical value, emerging technologies such as artificial intelligence are being integrated into plaque quantification platforms, placing more advanced measures of plaque burden at the forefront of coronary plaque evaluation. In this review, we summarize recent clinical data on coronary artery calcium scoring and coronary CT angiography plaque quantification in the evaluation of adverse atherosclerotic cardiovascular disease in patients with and without chest pain, highlight how these methods compare to invasive quantification approaches, and directly compare the performance characteristics of coronary artery calcium scoring and coronary CT angiography.