Disease Activity in Mitral Annular Calcification

Abstract

Background: Mitral annular calcification (MAC) is associated with cardiovascular events and mitral valve dysfunction. However, the underlying pathophysiology remains incompletely understood. In this prospective longitudinal study, we used a multimodality approach including positron emission tomography, computed tomography, and echocardiography to investigate the pathophysiology of MAC and assess factors associated with disease activity and progression. Methods: A total of 104 patients (age 72±8 years, 30% women) with calcific aortic valve disease, therefore predisposed to MAC, underwent 18 F-sodium fluoride (calcification activity) and 18 F-Fluorodeoxyglucose (inflammation activity) positron emission tomography, computed tomography calcium scoring, and echocardiography. Sixty patients underwent repeat computed tomography and echocardiography after 2 years. Results: MAC (mitral annular calcium score >0) was present in 35 (33.7%) patients who had increased 18 F-fluoride (tissue-to-background ratio, 2.32 [95% CI, 1.81–3.27] versus 1.30 [1.22–1.49]; P <0.001) and 18 F-Fluorodeoxyglucose activity (tissue-to-background ratio, 1.44 [1.37–1.58] versus 1.17 [1.12–1.24]; P <0.001) compared with patients without MAC. MAC activity ( 18 F-fluoride uptake) was closely associated with the local calcium score and 18 F-Fluorodeoxyglucose uptake, as well as female sex and renal function. Similarly, MAC progression was closely associated with local factors, in particular, baseline MAC. Traditional cardiovascular risk factors and calcification activity in bone or remote atherosclerotic areas were not associated with disease activity nor progression. Conclusions: MAC is characterized by increased local calcification activity and inflammation. Baseline MAC burden was associated with disease activity and the rate of subsequent progression. This suggests a self-perpetuating cycle of calcification and inflammation that may be the target of future therapeutic interventions.

Coronary 18 F-Fluoride Uptake and Progression of Coronary Artery Calcification

“…Here, we have confirmed that increased 18 F-fluoride uptake provides an assessment of calcification activity within the coronary arteries, with uptake predicting progression in macroscopic calcium measured in individual plaques on CT (Figure 1 ), similar to previous results in the aortic valve and mitral valve annulus. 28 , 29 Indeed, while calcium scores remained static in lesions without uptake, there was progression of calcification in plaques with increased 18 F-fluoride uptake, with an ≈50% increase in median calcium score and calcium mass in as little as 12 months. Furthermore, the median change in calcium score in individual lesions with 18 F-fluoride uptake was almost 20× greater than the change in calcium score in those without uptake.…”

Iterative reconstruction incorporating background correction improves quantification of [18F]-NaF PET/CT images of patients with abdominal aortic aneurysm

“…BC image, A B without much effort to manually exclude the aneurysm part close to the bone. Although the BC technique was used in this study to effectively remove the spill in activity from the bone into the aneurysm, the application is not limited to aneurysm imaging, but in principle it can be applied to other mappable regions such as the aortic valves 19 and the mitral annulus 42 where an automated (or semiautomated) ROI can be drawn on the BC image without much effort to manually exclude the uptake from the hot region. Further study is, however, needed to validate this.…”

Chronic kidney disease and valvular heart disease: conclusions from a Kidney Disease: Improving Global Outcomes (KDIGO) Controversies Conference

“…MAC progression appears to be more closely associated with the extent of baseline MAC and its inflammatory component, assessed by 18 F-fluorodeoxyglucose activity, than with eGFR. 47 The presence of MAC has been associated with mitral regurgitation, stenosis, or mixed valvular disease. In addition, MAC is associated with greater cardiovascular risk, and higher risk for endocarditis, and atrial arrhythmias.…”