Distribution of Mitral Annular and Aortic Valve Calcium as Assessed by Unenhanced Multidetector Computed Tomography

The Associations of Aortic Valve Sclerosis, Aortic Annular Increased Reflectivity, and Mitral Annular Calcification with Subsequent Aortic Stenosis in Older Individuals: Findings from the Cardiovascular Health Study

BACKGROUND

Although aortic valve sclerosis (AVS) is well described as preceding aortic stenosis (AS), the associations of AS with antecedent mitral annular calcification (MAC) and aortic annular increased reflectivity (AAIR) have not been characterized. In a population-based prospective study, the authors evaluated whether MAC, AAIR, and AVS are associated with the risk for incident AS.

METHODS

Among participants of the Cardiovascular Health Study free of AS at the 1994-1995 visit, the presence of MAC, AAIR, AVS, and the combination of all three was evaluated in 3,041 participants. Cox proportional-hazards regression was used to assess the association between the presence of calcification and the incidence of moderate or severe AS in three nested models adjusting for factors associated with atherosclerosis and inflammation both relevant to the pathogenesis of AS.

RESULTS

Over a median follow-up period of 11.5 years (interquartile range, 6.7-17.0 years), 110 cases of incident moderate or severe AS were ascertained. Strong positive associations with incident moderate or severe AS were found for all calcification sites after adjustment for the main model covariates: AAIR (hazard ratio [HR], 2.90; 95% CI, 1.95-4.32; P < .0005), AVS (HR, 2.20; 95% CI, 1.44-3.37; P < .0005), MAC (HR, 1.67; 95% CI, 1.14-2.45; P = .008), and the combination of all three (HR, 2.50; 95% CI, 1.65-3.78; P < .0005). In a secondary analysis, the risk for AS increased with the number of sites at which calcification was present.

CONCLUSIONS

In a large cohort of community-dwelling elderly individuals, there were strong associations between each of AAIR, AVS, MAC, and the combination of the three and incident moderate or severe AS. The novel finding that AAIR had a particularly strong association with incident AS, even after adjusting for other calcification sites, suggests its value in identifying individuals at risk for AS and potential inclusion in routine assessment by transthoracic echocardiography.

Systolic Anterior Motion of the Mitral Valve in the Presence of Annular Calcification

BACKGROUND

Mitral annular calcification (MAC) has been reported as a possible cause of systolic anterior motion (SAM) of the mitral valve and dynamic left ventricular outflow tract (LVOT) obstruction. While morphologic features predisposing to SAM in other clinical settings have been described, patients with MAC+SAM have not been systematically investigated. We hypothesized that bulky calcium deposits in the mitral annulus could displace the valve toward the septum, thus promoting development of SAM.

METHODS

We studied 30 patients with severe MAC who had SAM with septal contact. Three comparator groups (matched for age and sex) were developed: 30 controls without MAC or SAM, 30 with severe MAC but no SAM, and 30 with SAM but no MAC.

RESULTS

Significant differences were found across groups for mitral valve coaptation point-septal distance (CSD), anterior mitral leaflet (AML) length, left ventricular diastolic dimension, and ejection fraction. Comparing all MAC subjects (n = 60) with controls, CSD was less (20.5 ± 4.1 vs 23.2 ± 3.7 mm, P = .003) and ejection fraction was higher (67.7% ± 7.8% vs 60.9% ± 6.4%, P < .0001) in MAC patients. Within MAC subjects AML was longer (21.9 ± 3.0 vs 17.4 ± 2.2 mm, P < .0001) and CSD was smaller (18.0 ± 2.7 vs 23.1 ± 3.6 mm, P < .0001) when SAM was present despite similar height of the calcium bar in the 2 MAC groups (12.4 ± 2.9 vs 11.1 ± 3.1 mm, P = .11). Regression analysis confirmed AML length and CSD as independent predictors of SAM. MAC+SAM patients also had more echocardiographic risk factors for SAM (acute aortomitral angle, small LVOT, long AML, small CSD, and presence of a septal bump) than MAC/no-SAM patients (3.4 ± 0.9 vs 1.8 ± 1.0, P < .0001).

CONCLUSIONS

Bulky MAC appears to contribute to dynamic LVOT obstruction when it accumulates in such a way that the mitral valve is displaced anteriorly toward the septum. However, other features are also associated with SAM in these patients, particularly a long AML. A combination of morphologic features and favorable hemodynamics may be needed for SAM to develop in patients with severe MAC.

Sex-and race-specific burden of aortic valve calcification among older adults without overt coronary heart disease: The Atherosclerosis Risk in Communities Study

BACKGROUND AND AIMS

The prevalence of aortic valve calcification (AVC) increases with age. However, the sex-and race-specific burden of AVC and associated cardiovascular risk factors among adults ≥75 years are not well studied.

METHODS

We calculated the sex-and race-specific burden of AVC among 2283 older Black and White adults (mean age:80.5 [SD:4.3] years) without overt coronary heart disease from the Atherosclerosis Risk in Communities Study who underwent non-contrast cardiac-gated CT-imaging at visit 7 (2018-2019). Using Poisson regression with robust variance, we calculated the adjusted prevalence ratios (aPR) of the association of AVC with cardiovascular risk factors.

RESULTS

The overall AVC prevalence was 44.8%, with White males having the highest prevalence at 58.2%. The prevalence was similar for Black males (40.5%), White females (38.9%), and Black females (36.8%). AVC prevalence increased significantly with age among all race-sex groups. The probability of any AVC at age 80 years was 55.4%, 40.0%, 37.3%, and 36.2% for White males, Black males, White females, and Black females, respectively. Among persons with prevalent AVC, White males had the highest median AVC score (100.9 Agatston Units [AU]), followed by Black males (68.5AU), White females (52.3AU), and Black females (46.5AU). After adjusting for cardiovascular risk factors, Black males (aPR:0.53; 95%CI:0.33-0.83), White females (aPR:0.68; 95%CI:0.61-0.77), and Black females (aPR:0.49; 95%CI:0.31-0.77) had lower AVC prevalence compared to White males. In addition, systolic blood pressure, non-HDL-cholesterol, and lipoprotein (a) were independently associated with AVC, with no significant race/sex interactions.

CONCLUSIONS

AVC, although highly prevalent, was not universally present in this cohort of older adults. White males had ∼50-60% higher prevalence than other race-sex groups. Moreover, cardiovascular risk factors measured in older age showed significant association with AVC.

Estimation of Aortic Valve Calcium Score Based on Angiographic Phase Versus Reduction of Ionizing Radiation Dose in Computed Tomography

The aim of the study was to evaluate the estimation efficacy of aortic valve calcium score (AVCS) based on the multislice computed tomography (MSCT) angiographic phase. The evaluation of the reduced amount of ionizing radiation dose was performed because of this estimation. The study included 51 consecutive patients who qualified for transcatheter aortic valve implantation (TAVI) (78.59 ± 5.72 years). All subjects underwent MSCT: in the native phase dedicated to AVCS as well as angiographic phases aimed to morphologically assess the aortic ostium and arterial accesses for TAVI. Based on the native phase, an AVCS assessment was performed for axial reconstructions at 3.0 mm and 2.0 mm slice thickness (AVCS_native3.0 and AVCS_native2.0). Based on the angiographic phase AVCS was estimated for axial reconstruction at 0.6 mm slice thickness with increased values of lesion density in aortic valve cusps/aortic valve annulus, which is considered a calcification, from a typical value of 130 HU to 500 HU and 600 HU (AVCS_{CTA0.6 500 HU} and AVCS_{CTA0.6 600 HU}). Mathematical formulations were developed, allowing for AVCS native calculation based on AVCS values estimated based on the angiographic phase: AVCS_native3.0 = 813.920 + 1.510 AVCS_{CTA0.6 500 HU}; AVCS_native3.0 = 1235.863 + 1.817 AVCS_{CTA0.6 600 HU}; AVCS_native2.0 = 797.471 + 1.393 AVCS_{CTA0.6 500 HU}; AVCS_native2.0 = 1228.310 + 1.650 AVCS_{CTA0.6 600 HU}. The amount of a potential reduction in dose length product (DLP) in the case of AVCS estimation was 4.45 ± 1.54%. In summary, relying solely on the angiographic phase of MSCT examination before TAVI, it is possible to conclusively estimate AVCS. This estimation results in a marked reduction in radiation dose in MSCT.

Predictors of calcification distribution in severe tricuspid aortic valve stenosis

We investigated aortic valve calcification (AVC) distribution and predictors for leaflet calcification patterns in patients with severe tricuspid aortic valve stenosis undergoing transcatheter aortic valve replacement (TAVR). Patients undergoing routine multi-sliced computed tomography (MSCT) for procedural planning were enrolled. MSCT data were transferred to a dedicated workstation for evaluation (3mensio Structural Heart™, Pie Medical Imaging BV, Maastricht, The Netherlands) and analyzed. Participants were separated into asymmetrical (AC) and symmetrical (SC) leaflet calcification and potential predictors for calcification distribution were identified with univariate and multivariate regression analysis. 567 Participants with severe tricuspid AS were divided into asymmetrical (AC, n = 443; 78.1%) and symmetrical (SC, n = 124; 21.9%) AVC. In AC, the non-coronary cusp was the most calcified cusp (n = 238; 57.7%). SC is more common in females (AC/SC: 49.2% vs. 67.7%; p < 0.0001). AVC was more severe in patients with AC, who also have larger aortic root dimensions. Multivariate analysis depicted, inter alia, left ventricular outflow tract (LVOT) calcification < 25 Agatston units (OR 1.81 [1.09-3.00], p = 0.021), a mean pressure gradient < 36 mmHg (OR 1.77 [1.03-3.05], p = 0.039), and an annulo-apical angle > 67° (OR 1.68 [1.00-2.80], p = 0.049) as predictors for SC, although with only moderate predictive value. Data from this retrospective analysis indicate that SC occurs more frequently in females. The cumulative leaflet calcification burden is higher in patients with AC, who also present with larger aortic root dimensions. The predictive value for prominent calcification of different aortic valve cusps in AC patients was only low to moderate.Trial registration number: NCT01805739.

A study on the prevalence, distribution and related factors of heart valve calcification using coronary CT angiography

Background

The concept of active atherosclerotic disease has been accepted for heart valve calcification (HVC). We investigated prevalence, distribution and related factors of HVC in patients who had undergone coronary CT angiography (CCTA).

Methods

Subjects were consecutive 200 patients who underwent CCTA. The prevalence and the distribution of HVC using ECG gated non-contrast CT were investigated. Logistic regression analysis and simple regression analysis for factors associated with presence of the calcification and quantitative calcification in the aortic and mitral valve were conducted.

Results

HVC was detected in 48.0%. Aortic valve calcification (AVC) was found in 92 cases, the most, followed by mitral valve calcification (MVC) in 25 cases, pulmonary valve in 3 cases, and tricuspid valve in 1 case. Although the left coronary cusp showed the most in 65.2%, no statistic significant difference for Agatston score was detected among each cusp in AVC. Multiple logistic regression analysis showed that age (OR:1.211, 95%C.I.:1.0716-1.1728, p < 0.0001) and coronary artery calcium score (CACS) grade (grade2 OR:7.3393, 95%C.I.:1.7699-30.4349, p = 0.0060, grade3 OR:7.2214, 95%C.I.:1.4376-36.2762, p = 0.0164) were significant factors associated with presence of AVC. The significant factors associated with quantitative AVC were age (p = 0.0043), dyslipidemia (p = 0.0117), and statin use (p = 0.0221). Only age (OR:1.1589, 95%C.I.:1.0726-1.2520, p = 0.0002) was significant factor related to presence of MVC. No significant related factor was found in quantitative MVC.

Conclusions

There was an association between presence of AVC and CACS, but not a significant association with presence of MVC. Neither quantitative AVC nor MVC had a significant association with CACS or coronary artery disease.

Cardiac Computed Tomography and Magnetic Resonance Imaging in the Evaluation of Mitral and Tricuspid Valve Disease

Transcatheter interventions to treat mitral and tricuspid valve disease are becoming increasingly available because of the growing number of elderly patients with significant comorbidities or high operative risk. Thorough clinical and imaging evaluation in these patients is essential. The latter involves both characterization of the mechanism and severity of valvular disease as well as determining the hemodynamic consequences and extent of ventricular remodeling, which is an important predictor of future outcomes. Moreover, an assessment of the suitability and risk of complications associated with device-specific therapies is also an important component of the preprocedural evaluation in this cohort. Although echocardiography including 2-dimensional and 3-dimensional methods has an important role in the initial assessment and procedural guidance, cross-sectional imaging, including both computed tomographic imagning and cardiac magnetic resonance imaging, is increasingly being integrated into the evaluation of mitral and tricuspid valve disease. In this review, we discuss the role of cross-sectional imaging in mitral and tricuspid valve disease, primarily valvular regurgitation assessment, with an emphasis on the preprocedural evaluation and implications for transcatheter interventions.