Association of mitral annulus calcification with high-sensitivity C-reactive protein, which is a marker of inflammation

The Association of Mitral Annular Calcification With Cardiovascular and Noncardiovascular Outcomes: The Multi-Ethnic Study of Atherosclerosis

Mitral annular calcification (MAC) may be a potential marker of biologic aging. However, the association of MAC with noncardiovascular measures, including bone mineral density (BMD), incident renal failure, dementia, and noncardiovascular mortality, is not well-studied in a multiracial cohort. We used data from 6,814 participants (mean age: 62.2 ± 10.2 years, 52.9% women) without cardiovascular disease at baseline in the Multi-Ethnic Study of Atherosclerosis. MAC was assessed with noncontrast cardiac computed tomography at study baseline. Using multivariable-adjusted linear and logistic regression, we assessed the cross-sectional association of MAC with BMD and walking pace. Furthermore, using Cox proportional hazards, we evaluated the association of MAC with incident renal failure, dementia, and all-cause mortality. In addition, we assessed the association of MAC with cardiovascular and noncardiovascular mortality using competing risks regression. The prevalence of MAC was 9.5% and was higher in women (10.7%) than in men (8.0%). MAC was associated with low BMD (coefficient -0.04, 95% confidence interval [CI] -0.06 to -0.02), with significant interaction by gender (p-interaction = 0.035). MAC was, however, not associated with impaired walking pace (odds ratio 1.09, 95% CI 0.89 to 1.33). Compared with participants without MAC, those with MAC had an increased risk of incident renal failure, albeit nonsignificant (hazard ratio [HR] 1.18, 95% CI 0.95 to 1.45), and a significantly higher hazards of dementia (HR 1.36, 95% CI 1.10 to 1.70). In addition, participants with MAC had a substantially higher risk of all-cause (HR 1.47, 95% CI 1.29 to 1.69), cardiovascular (subdistribution HR 1.39, 95% CI 1.04 to 1.87), and noncardiovascular mortality (subdistribution HR 1.35, 95% CI 1.14 to 1.60) than those without MAC. MAC ≥100 versus <100 was significantly associated with reduced BMD, incident renal failure, dementia, all-cause, cardiovascular, and noncardiovascular mortality. In conclusion, MAC was associated with reduced BMD and dementia and all-cause, cardiovascular, and noncardiovascular mortality in this multiracial cohort. Thus, MAC may be a marker not only for atherosclerotic burden but also for other metabolic and inflammatory factors that increase the risk of noncardiovascular outcomes and death from other causes.

Association of Inflammatory and Metabolic Biomarkers with Mitral Annular Calcification in Type 2 Diabetes Patients

(1) Background: Type 2 diabetes mellitus (T2DM) contributes to cardiovascular disease and related mortality through the insidious effects of insulin resistance and chronic inflammation. Mitral annular calcification (MAC) is one such degenerative process promoted by T2DM. (2) Methods: This is a post hoc analysis of insulin resistance, inflammation, and hepatic steatosis markers in T2DM patients without atherosclerotic manifestations, but with incidental echocardiographic detection of mild MAC. (3) Results: 138 consenting patients were 49.3% men, 57.86 years old, with a history of T2DM of 6.16 years and HbA_1c 8.06%, of whom sixty had mild MAC (43.47%). The statistically significant differences between patients with/without MAC were higher HOMA C-peptide and C-peptide index for insulin resistance, higher TNF-α for inflammation, and lower estimated glomerular filtration rate. High-sensitive C-reactive protein (hsCRP) was significantly associated with insulin resistance and the strength of the relationship was higher in the MAC group. Predictive of MAC were TNF-α, HOMA C-peptide, and especially hepatic steatosis and hypertension. (4) Conclusions: MAC was more prevalent than reported in the literature. Insulin resistance and inflammation were predictive of MAC, but significant markers differ across studies. Widely available routine tests and echocardiographic assessments are useful in the early identification of mitral annular calcifications in diabetes patients.

Valvular calcification and risk of peripheral artery disease: the Multi-Ethnic Study of Atherosclerosis (MESA)

AIMS

The detection of cardiac valvular calcification on routine imaging may provide an opportunity to identify individuals at increased risk for peripheral artery disease (PAD). We investigated the associations of aortic valvular calcification (AVC) and mitral annular calcification (MAC) with risk of developing clinical PAD or a low ankle-brachial index (ABI).

METHODS AND RESULTS

AVC and MAC were measured on cardiac computed tomography in 6778 Multi-Ethnic Study of Atherosclerosis participants without baseline PAD between 2000 and 2002. Clinical PAD was ascertained through 2015. Incident low ABI, defined as ABI <0.9 and decline of ≥0.15, was assessed among 5762 individuals who had an ABI >0.9 at baseline and at least one follow-up ABI measurement 3-10 years later. Adjusted Cox proportional hazards and Poisson regression modelling were used to determine the association of valvular calcification with clinical PAD and low ABI, respectively. There were 117 clinical PAD and 198 low ABI events that occurred over a median follow-up of 14 years and 9.2 years, respectively. The presence of MAC was associated with an increased risk of clinical PAD [hazard ratio 1.79; 95% confidence interval (CI) 1.04-3.05] but not a low ABI (rate ratio 1.28; 95% CI 0.75-2.19). No significant associations were noted for the presence of AVC and risk of either clinical PAD.

CONCLUSION

MAC is associated with an increased risk of developing clinical PAD. Future studies are needed to corroborate our findings and better understand whether MAC holds any predictive value as a risk marker for PAD.

Mitral annular calcification predicted major cardiovascular events in patients presented with acute coronary syndrome and underwent percutaneous coronary intervention

Background: Despite the presence of several clinical studies evaluating the association of atherosclerosis and MAC, no data is present regarding the value of MAC in predicting CV adverse events in patients with acute coronary syndrome (ACS).Methods: Prospective, observational cohort study including 314 patients presented with ACS and underwent percutaneous coronary intervention (PCI). MAC was defined by increased echodensity located at the junction of the atrioventricular groove and posterior mitral leaflet on the parasternal long-axis, short-axis, or apical four-chamber view. Patients were followed for a median 25.1 (23.1-26.5) months for any occurrence of major adverse cardiovascular events (MACE).Results: Among 316 patients 46 (14%) had MAC. Seventy (22.1%) patients had MACE during the follow-up. Patients with MACE had higher creatinine, white blood cell count (WBC), C-reactive protein (CRP), peak troponin I, glucose level at admission compared to those without MACE. Age (HR = 1.026, 95% CI = 1.004-1.049; p = .023), myocardial blush grade (HR = 0.637, 95% CI = 0.480-0.846; p = .008), MAC (HR = 2.429, 95% CI = 1.126-5.239; p = .026), and WBC at admission (HR = 1.079, 95% CI = 1.007-1.157; p = .031) were independent predictors for MACE.Conclusion: In patients presented with ACS and underwent PCI, MAC detected by TTE was an independent predictor for MACE during the long-term follow-up.

Degenerative Mitral Stenosis: From Pathophysiology to Challenging Interventional Treatment

Mitral stenosis (MS) is characterized by obstruction of left ventricular inflow as a result of narrowing of the mitral valve orifice. Although its prevalence has declined over the last decade, especially in developed countries, it remains an important cause of morbidity and mortality.  The most often cause of MS worldwide is still postrheumatic mitral valve disease. However, in developed countries, degenerative or calcific changes cause MS in a siginificant proportion of patients. Although the range of treatment for mitral valve disease has grown over the years in parallel with transcatheter therapies for aortic valve disease, these improvements in mitral valve disease therapy have experienced slower development. This is mainly due to the more complex anatomy of the mitral valve and entire mitral apparatus, and the interplay of the mitral valve with the left ventricle which hinders the development of effective implantable mitral valve devices. This is especially the case with degenerative MS where percutaneous or surgical comissurotomy is rarely employed due to the presence of extensive annular calcification and at the base of leaflets, without associated commissural fusion. However, the last few years have witnessed innovations in transcatheter interventional procedures for degenerative MS which consequently hinted that in the future, transcatheter mitral valve replacement could be the treatment of choice for these patients.

Obesity and inflammation: the linking mechanism and the complications

Obesity is the accumulation of abnormal or excessive fat that may interfere with the maintenance of an optimal state of health. The excess of macronutrients in the adipose tissues stimulates them to release inflammatory mediators such as tumor necrosis factor α and interleukin 6, and reduces production of adiponectin, predisposing to a pro-inflammatory state and oxidative stress. The increased level of interleukin 6 stimulates the liver to synthesize and secrete C-reactive protein. As a risk factor, inflammation is an imbedded mechanism of developed cardiovascular diseases including coagulation, atherosclerosis, metabolic syndrome, insulin resistance, and diabetes mellitus. It is also associated with development of non-cardiovascular diseases such as psoriasis, depression, cancer, and renal diseases. On the other hand, a reduced level of adiponectin, a significant predictor of cardiovascular mortality, is associated with impaired fasting glucose, leading to type-2 diabetes development, metabolic abnormalities, coronary artery calcification, and stroke. Finally, managing obesity can help reduce the risks of cardiovascular diseases and poor outcome via inhibiting inflammatory mechanisms.

Effect of Mitral Annular Calcium on Left Ventricular Diastolic Parameters

Assessment of left ventricular (LV) diastolic function by Doppler flow imaging and tissue Doppler is an integral part of the echocardiographic examination. Mitral annular calcium (MAC) is frequently encountered on echocardiography. The aim of this study was to assess the impact of MAC, quantitatively measured by computed tomography scan, on echocardiographic LV diastolic parameters. We included 155 patients aged ≥65 years. Computed tomography reconstructions of the mitral annulus were created, and calcium identified and quantified by Agatston technique. Calcium locations were assigned using an overlaid template depicting the annular segments in relation to surrounding anatomic structures. Echocardiographic assessment of diastolic function was performed in standard fashion. Mean age was 77 years; 49% were men; and 43% were black. Patients with MAC had lower septal e' (p = 0.003), lateral e' (p = 0.04), and average e' (p = 0.01) compared with those without MAC. They also had a higher E-wave velocity (p = 0.01) and E/e' ratio (p <0.001). When evaluated by severity of MAC, and after adjustment for multiple clinical factors, there was a graded (inverse) relation between MAC severity and septal e' (p = 0.01), lateral e' (p = 0.01), and average e' (p = 0.01). In conclusion, LV diastolic parameters, as measured by Doppler echocardiography, are altered in the presence of MAC. This could be due to direct effects of MAC on annular function or might reflect truly reduced diastolic function. Interpretation of diastolic parameters in patients with MAC should be performed with caution.