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Background Lipoprotein(a) (Lp(a)) is a potent causal risk factor for cardiovascular events and mortality. However, its relationship with subclinical atherosclerosis, as defined by arterial calcification, remains unclear. This study uses the ARIC (Atherosclerosis Risk in Communities Study) to evaluate the relationship between Lp(a) in middle age and measures of vascular and valvular calcification in older age. Methods and Results Lp(a) was measured at ARIC visit 4 (1996-1998), and coronary artery calcium (CAC), together with extracoronary calcification (including aortic valve calcium, aortic valve ring calcium, mitral valve calcification, and thoracic aortic calcification), was measured at visit 7 (2018-2019). Lp(a) was defined as elevated if >50 mg/dL and CAC/extracoronary calcification were defined as elevated if >100. Logistic and linear regression models were used to evaluate the association between Lp(a) and CAC/extracoronary calcification, with further stratification by race. The mean age of participants at visit 4 was 59.2 (SD 4.3) years, with 62.2% women. In multivariable adjusted analyses, elevated Lp(a) was associated with higher odds of elevated aortic valve calcium (adjusted odds ratio [aOR], 1.82; 95% CI, 1.34-2.47), CAC (aOR, 1.40; 95% CI, 1.08-1.81), aortic valve ring calcium (aOR, 1.36; 95% CI, 1.07-1.73), mitral valve calcification (aOR, 1.37; 95% CI, 1.06-1.78), and thoracic aortic calcification (aOR, 1.36; 95% CI, 1.05-1.77). Similar results were obtained when Lp(a) and CAC/extracoronary calcification were examined on continuous logarithmic scales. There was no significant difference in the association between Lp(a) and each measure of calcification by race or sex. Conclusions Elevated Lp(a) at middle age is significantly associated with vascular and valvular calcification in older age, represented by elevated CAC, aortic valve calcium, aortic valve ring calcium, mitral valve calcification, thoracic aortic calcification. Our findings encourage assessing Lp(a) levels in individuals with increased cardiovascular disease risk, with subsequent comprehensive vascular and valvular assessment where elevated.

Background: Nonalcoholic fatty liver disease (NAFLD) is a leading cause of end‐stage liver disease. NAFLD diagnosis and follow‐up relies on a combination of clinical data, liver imaging, and/or liver biopsy. However, intersite imaging differences impede diagnostic consistency and reduce the repeatability of the multisite clinical trials necessary to develop effective treatments. Purpose/Hypothesis: The goal of this pilot study was to harmonize commercially available 3 T magnetic resonance imaging (MRI) measurements of liver fat and stiffness in human participants across academic sites and MRI vendors. Study Type: Cohort. Subjects: Four community‐dwelling adults with obesity. Field strength/Sequence: 1.5 and 3 T, multiecho 3D imaging, PRESS, and GRE. Assessment: Harmonized proton density fat fraction (PDFF) and magnetic resonance spectroscopy (MRS) protocols were used to quantify the FF of synthetic phantoms and human participants with obesity using standard acquisition parameters at four sites that had four different 3 T MRI instruments. In addition, a harmonized magnetic resonance elastography (MRE) protocol was used to quantify liver stiffness among participants at two different sites at 1.5 and 3 T field strengths. Data were sent to a single data coordinating site for postprocessing. Statistical Tests: Linear regression in MATLAB, ICC analyses using SAS 9.4, one‐sided 95% confidence intervals for the ICC. Results: PDFF and MRS FF measurements were highly repeatable among sites in both humans and phantoms. MRE measurements of liver stiffness in three individuals at two sites using one 1.5 T and one 3 T instrument showed repeatability that was high although lower than that of MRS and PDFF. Conclusions: We demonstrated harmonization of PDFF, MRS, and MRE‐based quantification of liver fat and stiffness through synthetic phantoms, traveling participants, and standardization of postprocessing analysis. Multisite MRI harmonization could contribute to multisite clinical trials assessing the efficacy of interventions and therapy for NAFLD. Level of Evidence: 2 Technical Efficacy Stage: 2 [ABSTRACT FROM AUTHOR]

Purpose: To evaluate precision of a software-based liver surface nodularity (LSN) score derived from CT images.Methods: An anthropomorphic CT phantom was constructed with simulated liver containing smooth and nodular segments at the surface and simulated visceral and subcutaneous fat components. The phantom was scanned multiple times on a single CT scanner with adjustment of image acquisition and reconstruction parameters (N = 34) and on 22 different CT scanners from 4 manufacturers at 12 imaging centers. LSN scores were obtained using a software-based method. Repeatability and reproducibility were evaluated by intraclass correlation (ICC) and coefficient of variation. Using abdominal CT images from 68 patients with various stages of chronic liver disease, inter-observer agreement and test-retest repeatability among 12 readers assessing LSN by software- vs. visual-based scoring methods were evaluated by ICC.Results: There was excellent repeatability of LSN scores (ICC:0.79-0.99) using the CT phantom and routine image acquisition and reconstruction parameters (kVp 100-140, mA 200-400, and auto-mA, section thickness 1.25-5.0 mm, field of view 35-50 cm, and smooth or standard kernels). There was excellent reproducibility (smooth ICC: 0.97; 95% CI 0.95, 0.99; CV: 7%; nodular ICC: 0.94; 95% CI 0.89, 0.97; CV: 8%) for LSN scores derived from CT images from 22 different scanners. Inter-observer agreement for the software-based LSN scoring method was excellent (ICC: 0.84; 95% CI 0.79, 0.88; CV: 28%) vs. good for the visual-based method (ICC: 0.61; 95% CI 0.51, 0.69; CV: 43%). Test-retest repeatability for the software-based LSN scoring method was excellent (ICC: 0.82; 95% CI 0.79, 0.84; CV: 12%).Conclusion: The software-based LSN score is a quantitative CT imaging biomarker with excellent repeatability, reproducibility, inter-observer agreement, and test-retest repeatability. [ABSTRACT FROM AUTHOR]

Background: Pulse wave velocity (PWV) is a noninvasive measure of arterial stiffness and predictor of cardiovascular disease. However, the association between PWV and vascular calcification across different vascular beds has not been fully investigated. This study aimed to quantify the association between PWV and multiterritory calcification and to explore whether PWV can identify individuals with vascular calcification beyond traditional risk factors., Methods and Results: Among 1351 older adults (mean age, 79.2 years [SD, 4.1]) from the ARIC (Atherosclerosis Risk in Communities) study, we measured segment-specific PWVs: heart-carotid, heart-femoral, carotid-femoral, heart-ankle, brachial-ankle, and femoral-ankle. Dependent variables were high calcium score (≥75th percentile of Agatston score) across different vascular beds: coronary arteries, aortic valve ring, aortic valve, mitral valve, ascending aorta, and descending aorta. Quartiles of carotid-femoral, heart-femoral, heart-ankle, and brachial-ankle PWV were significantly associated with coronary artery calcium (eg, adjusted odds ratio [OR] for the highest versus lowest quartile of carotid-femoral PWV, 1.84 [95% CI, 1.24-2.74]). Overall, PWVs were most strongly associated with descending aorta calcification, with significant results for carotid-femoral, heart-femoral, heart-ankle, and brachial-ankle PWV (eg, adjusted OR for the highest versus lowest quartile of carotid-femoral PWV, 3.99 [95% CI, 2.61-6.17]). In contrast, femoral-ankle PWV was inversely associated with descending aorta calcification. Some PWVs improved the discrimination of coronary artery calcium and descending aorta calcification beyond traditional risk factors., Conclusions: The associations of PWV with vascular calcification varied substantially across segments, with descending aorta calcification most closely linked to PWVs. Our study suggests that some PWVs, especially carotid-femoral PWV, are helpful to identify individuals with coronary artery calcium and descending aorta calcification.