JACC. Cardiovascular imaging最新文献

Background: Approximately half of the patients with angina and nonobstructive coronary artery disease (ANOCA) have evidence of coronary microvascular dysfunction (CMD).

Objectives: This study aims to characterize patients with ANOCA by measuring their minimal microvascular resistance and to examine the pattern of vascular remodeling associated with these measurements.

Methods: The authors prospectively included patients with ANOCA undergoing continuous thermodilution assessment. Lumen volume and vessel-specific myocardial mass were quantified using coronary computed tomography angiography (CTA). CMD was defined as coronary flow reserve <2.5 and high minimal microvascular resistance as >470 WU.

Results: A total of 153 patients were evaluated; 68 had CMD, and 22 of them showed high microvascular resistance. In patients with CMD, coronary flow reserve was 1.9 ± 0.38 vs 3.2 ± 0.81 in controls (P < 0.001). Lumen volume was significantly correlated with minimal microvascular resistance (r = -0.59 [95% CI: -0.45 to -0.71]; P < 0.001). In patients with CMD and high microvascular resistance, lumen volume was 40% smaller than in controls (512.8 ± 130.3 mm³ vs 853.2 ± 341.2 mm³; P < 0.001). Epicardial lumen volume assessed by coronary CTA was independently associated with minimal microvascular resistance (P < 0.001). The predictive capacity of lumen volume from coronary CTA for detecting high microvascular resistance showed an area under the curve of 0.79 (95% CI: 0.69-0.88).

Conclusions: Patients with CMD and high minimal microvascular resistance have smaller epicardial vessels than those without CMD. Coronary CTA detected high minimal microvascular resistance with very good diagnostic capacity. Coronary CTA could potentially aid in the diagnostic pathway for patients with ANOCA.

Background: There is increasing evidence that coronary artery calcium (CAC) density is inversely associated with plaque vulnerability and atherosclerotic cardiovascular disease risk.

Objectives: A systematic review and meta-analysis were performed to examine the predictive value of CAC density for future cardiovascular events in asymptomatic individuals undergoing noncontrast CAC scoring computed tomography.

Methods: Electronic databases were searched for studies reporting CAC density and subsequent cardiovascular disease (CVD) or coronary heart disease (CHD) events. Two independent reviewers performed data extraction. Random-effects models were used to estimate pooled HRs and 95% CIs. Subgroup analyses were performed with studies stratified by CVD vs CHD events and by statin use.

Results: Of 5,029 citations, 5 studies with 6 cohorts met inclusion criteria. In total, 1,309 (6.1%) cardiovascular events occurred in 21,346 participants with median follow-up ranging from 5.2 to 16.7 years. Higher CAC density was inversely associated with risk of cardiovascular events following adjustment for clinical risk factors and CAC volume (HR: 0.80 per SD of density [95% CI: 0.72-0.89]; P < 0.01; I² = 0%). There was no significant difference in the pooled HRs for CVD vs CHD events (HR: 0.80 per SD [95% CI: 0.71-0.90] vs 0.74 per SD [95% CI: 0.59-0.94] respectively; P = 0.59). The protective association between CAC density and event risk persisted among statin-naive patients (HR: 0.79 per SD [95% CI: 0.70-0.89]; P < 0.01) but not statin-treated patients (HR: 0.97 per SD [95% CI: 0.77-1.22]; P = 0.78); the test for interaction indicated no significant between-group differences (P = 0.12).

Conclusions: Higher CAC density is associated with a lower risk of cardiovascular events when adjusted for risk factors and CAC volume. Future work may expand the contribution of CAC density in CAC scoring, and enhance its role in CVD risk assessment, treatment, and prevention.

Background: Recently, a standardized classification system for carotid atherosclerotic plaques, known as Carotid Plaque-RADS (Reporting and Data System), has been introduced. However, its capacity to improve stroke risk stratification beyond traditional stenosis degree assessment has not been extensively explored.

Objectives: This study aimed to determine the incremental prognostic value of Carotid Plaque-RADS over stenosis degree for stroke risk.

Methods: A retrospective analysis was performed on data from January 2010 to December 2021, involving subjects who underwent magnetic resonance imaging, computed tomography angiography, and ultrasound evaluations of the carotid artery. Disease-free survival (DFS) and recurrence-free survival (RFS) rates were compared across different stenosis degrees, Carotid Plaque-RADS categories, and their combination, using the Kaplan-Meier and net reclassification improvement formula.

Results: The study enrolled 1,378 subjects. During a follow-up period of 57 ± 25 months, 4.6% of 987 asymptomatic individuals and 16.9% of 391 subjects with stroke history experienced initial and recurrent strokes, respectively. Significant differences in DFS and RFS rates were found between subjects with mild/moderate and severe stenosis (P < 0.001). Significant differences in DFS rates were observed across Carotid Plaque-RADS categories (P < 0.001), with a notable decrease in DFS rates as Carotid Plaque-RADS categories increased from 1 to 4. This trend was similar in subjects with a history of stroke (P < 0.001). For patients with mild/moderate stenosis, significant differences in DFS and RFS rates were found between those with Carotid Plaque-RADS of ≥3 vs <3 (P < 0.001). Correct reclassification was achieved for 3.3% (32 of 979) of asymptomatic individuals and 9.7% (37 of 381) of subjects with a stroke history initially identified with mild/moderate stenosis. Incorporating Carotid Plaque-RADS with stenosis grading markedly improved risk assessment, resulting in net reclassification improvement of 63.8% for initial stroke and 47.8% for recurrent stroke prediction. The likelihood ratio test demonstrated that Carotid Plaque-RADS scores significantly enhanced the prognostic accuracy of stenosis degrees for both asymptomatic individuals and patients with a history of stroke (both P < 0.001).

Conclusions: Carotid Plaque-RADS significantly improves stroke risk stratification over traditional stenosis grading, especially in mild/moderate stenosis cases.