Association between aortic valve calcification measured on non-contrast computed tomography and aortic valve stenosis in the general population

Reproducibility of semi-quantitative assessment of aortic valve calcification and valve motion on echocardiography: a small-scale study

BACKGROUND

Aortic stenosis (AS) is the most common degenerative valve disease in high income countries. While hemodynamic metrics are commonly used to assess severity of stenosis, they are impacted by loading conditions and stroke volume and are often discordant. Anatomic valve assessments such as aortic valve calcification (AVC) and valve motion (VM) during transthoracic echocardiography (TTE) can offer clues to disease severity. The reliability of these semi-quantitatively assessed anatomic imaging parameters is unknown.

METHODS

This is a retrospective study of semi-quantitative assessment of AVC and valve VM on TTE. TTEs representing a range of AS severities were identified. The degree of calcification of the aortic valve and the degree of restricted VM were assessed in standard fashion. AVC scores and valve motion were assessed by readers with varied training levels blinded to the severity of AS. Correlation and inter-reader reliability between readers were assessed.

RESULTS

420 assessments (210 each for AVC and VM) were collected for 35 TTEs. Correlation of AVC for imaging trainees (fellows and students, respectively), ranged from 0.49 (95% CI 0.18-0.70) to 0.62 (95% CI 0.36-0.79) and 0.58 (95% CI 0.30-0.76) to 0.54 (95% CI 0.25-0.74) for VM. Correlation of anatomic assessments between echocardiographer-assigned AVC grades was r = 0.76 (95% CI 0.57-0.87)). The correlation between echocardiographer-assigned assessment of VM was r = 0.73 (95% CI 0.53-0.86), p < 0.00001 for both. For echocardiographer AVC assessment, weighted kappa was 0.52 (0.32-0.72), valve motion weighted kappa was 0.60 (0.42-0.78).

CONCLUSION

There was good inter-reader correlation between TTE-based semi-quantitative assessment of AVC and VM when assessed by board certified echocardiographers. There was modest inter-reader reliability of semi-quantitative assessments of AVC and VM between board certified echocardiographers. Inter-reader correlation and reliability between imaging trainees was lower. More reliable methods to assess TTE based anatomic assessments are needed in order to accurately track disease progression.

CLINICAL TRIAL NUMBER

STUDY00003100.

Correlation Between Cardiac Computed Tomography and Histopathology for Evaluating Patients with Aortic Valve Disease

BACKGROUND

The use of cardiac computed tomography (cardiac CT) and the quantification of the Agatston score for the evaluation of calcium of the aortic valve (AVC) has increased in different clinical contexts for diagnostic and prognostic purposes. This study aims to evaluate the correlation between cardiac CT and histopathology for the quantification of AVC.

METHODS

Ninety patients diagnosed with severe aortic valve dysfunction, of any etiology and regardless of the predominant type of injury, were included. Before the surgical event, a Cardiac CT were performed with Agatston Score measurement. The removed native valve was evaluated by a Pathologist, who provided a qualitative and quantitative evaluation of valve calcium. Calcium density was also analyzed by quantifying the area in pixel units obtained from photomicrographs. Follow-up was performed for four years after the aortic valve replacement.

RESULTS

Ninety patients were analyzed. The degenerative etiology predominated 63.3% (57 patients). The calcium load was different for the gender (p = 0.01) and type of valve injury (p = 0.0013). There was a positive correlation between the Agatston score, and the percentage of calcium reported by the pathologist in a conventional qualitative way (rs = 0.75, p < 0.001) and between the AVC and the Cote et al. score (rs = 0.77, p < 0.001). There was no difference in survival after aortic valve replacement concerning valve calcium load. Left ventricular dysfunction showed a significant difference in survival (p = 0.003, Log-rank).

CONCLUSION

There is a moderately high correlation between the Agatston score quantified by Cardiac CT and the histopathological evaluation. The severity of the calcification did not prove to be a predictor of death in the postsurgical follow-up.

Aortic valve calcification among elderly males from the general population, associated echocardiographic findings, and clinical implications

AIMS

Aortic valve calcification (AVC) detected by non-contrast computed tomography (NCCT) associates with morbidity and mortality in patients with aortic valve stenosis. However, the importance of AVC in the general population is sparsely evaluated. We intend to describe the associations between AVC score on NCCT and echocardiographic findings as left atrial (LA) dilatation, left ventricular (LV) hypertrophy, aortic valve area (AVA), peak velocity, mean gradient, and aortic valve replacement (AVR) in a population with AVC scores ≥300 AU.

METHODS AND RESULTS

Of 10 471 males aged 65-74 years from the Danish Cardiovascular Screening trial (DANCAVAS), participants with AVC score ≥300 AU were invited for transthoracic echocardiography and 828 (77%) of 1075 accepted the invitation. AVC scores were categorized (300-599, 600-799, 800-1199, and ≥1200 AU). AVR was obtained from registries. AVC was significantly associated with a steady increase in LA dilation (10.5%, 16.3%, 15.8%, 19.6%, P = 0.031), LV hypertrophy (3.9%, 6.6%, 8.9%, 10.1%, P = 0.021), peak velocity (1.7, 1.9, 2.1, 2.8 m/s, P = 0001), mean gradient (6, 8, 11, 19 mmHg, P = 0.0001), and a decrease in AVA (2.0, 1.9, 1.7, 1.3 cm2, P = 0.0001). The area under the curve was 0.79, 0.93, and 0.92 for AVA ≤1.5 cm2, peak velocity ≥3.0 m/s, and mean gradient ≥20 mmHg, respectively, and the associated optimal AVC score thresholds were 734, 1081, and 1019 AU. AVC > 1200 AU was associated with AVR (P < 0.0001).

CONCLUSION

Among males from the background population, increasing AVC scores were associated with LA dilatation, LV hypertrophy, AVA, peak aortic velocity, mean aortic gradient, and AVR.

Sex differences in aortic valve calcification in severe aortic valve stenosis: association between computer tomography assessed calcification and valvular calcium concentrations

AIMS

The aims of this study were to investigate the correlation and sex differences between total valve calcium, valve calcium concentration, and aortic valve calcification (AVC) in explanted valves from patients with severe aortic valve stenosis undergoing aortic valve replacement (AVR).

METHODS AND RESULTS

Sixty-nine patients with severe aortic stenosis (AS) scheduled for elective AVR underwent echocardiography and cardiac computed tomography (CT) prior to surgery (AVCin vivo) and CT of the explanted aortic valve (AVCex vivo). Explanted valves were prepared in acid solution, sonicated, and analysed with Arsenazo III dye to estimate total valve calcium and valve calcium concentration. Median AVCex vivo was 2082 (1421-2973) AU; mean valve calcium concentration was 1.43 ± 0.42 µmol Ca2+/mg tissue; median total valve calcium 156 (111-255) mg Ca2+, and valve calcium density 52 (35-81) mg/cm2. AVC displayed a strong correlation with total valve calcium (R2 = 0.98, P < 0.001) and a moderate correlation with valve calcium concentration (R2 = 0.62, P < 0.001). Valvular calcium concentration was associated with sex, aortic valve area, and mean gradient. After adjusting for age and estimated glomerular filtration rate, sex and mean gradient remained associated with valve calcium concentrations.

CONCLUSION

AVC score provides a strong estimate for total valve calcium but to a lesser degree calcium concentration in the valve tissue of patients with severe AS. Females presented lower valvular calcium concentrations than males irrespective of AS severity, adding evidence and providing support to the important point that sex differences in valvular calcium concentration in AS does not reflect valvular size.

Reporting incidental coronary, aortic valve and cardiac calcification on non-gated thoracic computed tomography, a consensus statement from the BSCI/BSCCT and BSTI

Incidental coronary and cardiac calcification are frequent findings on non-gated thoracic CT. We recommend that the heart is reviewed on all CT scans where it is visualised. Coronary artery calcification is a marker of coronary artery disease and it is associated with an adverse prognosis on dedicated cardiac imaging and on non-gated thoracic CT performed for non-cardiac indications, both with and without contrast. We recommend that coronary artery calcification is reported on all non-gated thoracic CT using a simple patient-based score (none, mild, moderate, severe). Furthermore, we recommend that reports include recommendations for subsequent management, namely the assessment of modifiable cardiovascular risk factors and, if the patient has chest pain, assessment as per standard guidelines. In most cases, this will not necessitate additional investigations. Incidental aortic valve calcification may also be identified on non-gated thoracic CT and should be reported, along with ancillary findings such as aortic root dilation. Calcification may occur in other parts of the heart including mitral valve/annulus, pericardium and myocardium, but in many cases these are an incidental finding without clinical significance.

The association between aortic valve calcification, cardiovascular risk factors, and cardiac size and function in a general population

To determine the presence and extent of aortic valve calcification (AVC) quantified by non-contrast cardiac computed tomography (NCCT), to determine the association between traditional cardiovascular risk factors and AVC score, and to evaluate the association between AVC and cardiac size and function assessed by echocardiography, in a general population aged 65-75 years. A random sample of 2060 individuals were invited to undergo NCCT through which their AVC score was assessed. Individuals with an AVC score ≥ 300 arbitrary units (AU) were invited for a transthoracic echocardiography together with age-matched controls. Descriptive statistics and multiple regression analyses were performed to identify risk factors associated with AVC and to describe associations between AVC score and echocardiographic findings. Of 2060 individuals invited 664 males and 636 females participated. Among those, 455 (68.5%) of males and 358 (56.3%) of females had AVC scores > 0 AU. The median AVC score was 6 AU (IQR 0-3064). Seventy-seven (11.6%) males and 20 (3.1%) females had an AVC score ≥ 300 AU. In a multiple regression analysis, age, sex, prior cardiovascular disease, smoking, and hypertension were associated with AVC score, while diabetes, hypercholesterolemia and kidney function were not. Individuals with AVC ≥ 300 AU had higher peak and mean aortic valve gradient, smaller indexed aortic valve area, greater left ventricular mass, and larger left atrial (LA) volume. In a random population sample of individuals aged 65-75 years, AVC was common and associated with most known cardiovascular risk factors. AVC ≥ 300 AU was associated with concentric remodeling and LA dilatation.

Feasibility Study of Advanced Cardiovascular Screening in Middle-Aged Patients with Diabetes

Purpose

Cardiovascular mortality remains high among patients with diabetes compared with the general population. The primary aim was to evaluate the interest in and demand for advanced cardiovascular screening in patients with diabetes; the secondary aim was to explore its efficiency in detecting unprotected subclinical cardiovascular disease (CVD).

Patients and Methods

In a cross-sectional design, randomly selected 40–60-year-old men and women with diabetes were invited to the screening trial. Screening encompassed (1) a comprehensive medical interview; (2) non-contrast computed tomography scanning to quantify coronary artery and aortic valve calcification, to measure left atrial size, to assess heart rhythm and to detect aortic and iliac dilatations; (3) ankle and brachial blood pressure measurements; and (4) blood and urine samples for measurements of HbA_1c, lipid profile, renal function, NT-pro B-type natriuretic peptide (pro-BNP) and albuminuria. Primary outcome was participation rate; secondary outcome was rate of unprotected subclinical CVD.

Results

Of 465 invited patients, 191 (41.1%) attended screening. The participation rate was 40% (95% CI:33–47) for males and 42% (95% CI:36–48) for females. Twenty-four patients were excluded due to previous CVD. The remaining patients’ mean age was 52 years; 58% were males. Subclinical CVD was found in 64%, with a male preponderance (males 75% (95% CI:66–83; females 49% (95% CI:37–60)). Presence of severe coronary artery calcification (score ≥ 400) showed a male preponderance (males 19% (95% CI:12–27); females 7% (95% CI:3–16)). Aortic valve calcification, enlarged left atrial volume, atrial fibrillation, aortic dilatations, peripheral artery disease or increased pro-BNP were uncommon, and without any sex differences. Unprotected subclinical CVD was very common, and medical treatment was intensified in 60% (95% CI:53–68) of patients.

Conclusion

We propose a feasible cardiovascular screening examination from which middle-aged patients with diabetes may benefit. However, the participation rate may be too low to warrant screening.

Association of aortic valve calcification and vitamin K antagonist treatment

Aims 

Vitamin K antagonists (VKAs) are suspected of causing aortic valve calcification (AVC). The objective of this study was to clarify whether patients undergoing VKA treatment have increased AVC scores compared to patients treated with new oral anticoagulants (NOACs) and patients who never have been treated with VKA/NOAC.

Methods and results 

We included participants from the population-based DANCAVAS trial (n = 15 048). Information on confounders was collected, and the AVC scores were measured on non-contrast computed tomography scans. The participants’ medication data, including VKA and NOAC data, were collected from the Danish National Health Service Prescription Database. The final population consisted of 14 604 participants (67.4 years, 95% men) of whom 873 had been treated with VKA and 602 with NOAC. The association between AVC score and duration of anticoagulant use was investigated in an adjusted zero-inflated negative binomial regression model. For every year treated with VKA, the AVC score increased, on average, by 6% [ratio of expected counts (RECs) = 1.06; 95% confidence interval (CI) 1.02–1.10] compared to non-use. The results were consistent in sensitivity analyses excluding patients with known cardiovascular disease and statin users (REC = 1.07; 95% CI 1.02–1.11 and REC = 1.10; 95% CI 1.03–1.17, respectively). NOAC treatment was not significantly associated with AVC score in any of the corresponding models (REC = 1.03, 1.02, and 0.96).

Conclusion 

Compared to no treatment with anticoagulants, VKA use was associated with increased AVC score, while a similar association could not be established for NOAC.

Prevalence and Prognostic Implications of Mitral and Aortic Valve Calcium in Patients With Chronic Kidney Disease

Calcium in the cardiac valves can be observed in patients with severe chronic kidney disease (CKD). However, the prevalence and prognostic implications of left-sided cardiac valve calcium in patients with stage 2 and 3 CKD (estimated glomerular filtration rate (eGFR) of 60 to 89 and 30 to 59 ml/min/1.73 m² respectively) is unknown. The present study investigates the prevalence of mitral and aortic valve calcium in patients with stage 2 and 3 CKD and evaluates its association with all-cause mortality. In patients with stage 2 and 3 CKD who underwent clinically indicated coronary computed tomography angiography, the presence of mitral and/or aortic valve calcium was assessed. Patients were divided into 2 groups according to the presence of mitral and/or aortic valve calcium on coronary computed tomography angiography. Patients were followed for the occurrence of all-cause mortality (primary end point). Of 204 stage 2 and 3 CKD patients (54% men, mean age 60 ± 10 years), 66 (32%) patients had mitral and/or aortic valve calcium. During a median follow-up of 6 years (IQR; 2, 9 years), 29 (14%) patients died. Patients with mitral and/or aortic valve calcium showed significantly higher mortality rates compared with patients without left-sided valve calcium (log-rank p = 0.009). Mitral valve calcium was independently associated with increased risk of all-cause mortality, whereas aortic valve calcium was not. In conclusion, the prevalence of left-sided valve calcium in patients with stage 2 and 3 CKD is high. Mitral valve calcium was independently associated with increased risk of all-cause mortality, whereas aortic valve calcium was not.

Effects of menaquinone-7 supplementation in patients with aortic valve calcification: study protocol for a randomised controlled trial

INTRODUCTION

Aortic stenosis is a common heart valve disease, and due to the growing elderly population, the prevalence is increasing. The disease is progressive with increasing calcification of the valve cusps. A few attempts with medical preventive treatment have failed; thus, presently, the only effective treatment of aortic stenosis is surgery. This study will examine the effect of menaquinone-7 (MK-7) supplementation on progression of aortic valve calcification (AVC). We hypothesise that MK-7 supplementation will slow down the calcification process.

METHODS AND ANALYSIS

In this multicenter and double-blinded, placebo-controlled study, 400 men aged 65-74 years with substantial AVC are randomised (1:1) to treatment with MK-7 (720 µg/day) supplemented by the recommended daily dose of vitamin D (25 µg/day) or placebo treatment (no active treatment) for 2 years. Exclusion criteria are treatment with vitamin K antagonist or coagulation disorders. To evaluate AVC score, a non-contrast CT scan is performed at baseline and repeated after 12 and 24 months of follow-up. Primary outcome is difference in AVC score from baseline to follow-up at 2 years. Intention-to-treat principle is used for all analyses.

ETHICS AND DISSEMINATION

There are no reported adverse effects associated with the use of MK-7. The protocol is approved by the Regional Scientific Ethical Committee for Southern Denmark (S-20170059) and the Data Protection Agency (17/19010). It is conducted in accordance with the Declaration of Helsinki. Positive as well as negative findings will be reported.

TRIAL REGISTRATION NUMBER

NCT03243890.

Resting heart rate and the incidence and progression of valvular calcium: The Multi-Ethnic Study of Atherosclerosis (MESA)

BACKGROUND AND AIMS

Left-sided valvular calcification is associated with cardiovascular disease (CVD) morbidity and mortality. Resting heart rate (RHR) may influence valvular calcium progression through shear stress. Whether RHR, an established CVD risk factor, is associated with valvular calcium progression is unknown. We assessed whether RHR predicts incidence and progression of mitral annular calcium (MAC) and aortic valve calcium (AVC) in a community-based cohort free of CVD at baseline.

METHODS

RHR was obtained from baseline electrocardiograms of 5498 MESA participants. MAC and AVC were quantified using Agatston scoring from cardiac computed tomography scans obtained at baseline and at a second examination during follow-up. We examined associations of RHR with incident MAC/AVC and annual change in MAC/AVC scores, after adjusting for demographics, CVD risk factors, physical activity, and atrioventricular nodal blocker use.

RESULTS

At baseline, participants had mean age of 62 ± 10 years and mean RHR of 63 ± 10 bpm; 12.3% and 8.9% had prevalent AVC and MAC, respectively. Over a median of 2.3 years, 4.1% and 4.5% developed incident AVC and MAC, respectively. Each 10 bpm higher RHR was significantly associated with incident MAC [Risk Ratio 1.17 (95% CI 1.03-1.34)], but not incident AVC. However, RHR was associated with AVC progression [β = 1.62 (0.45-2.80) Agatston units/year for every 10 bpm increment], but not MAC progression.

CONCLUSIONS

Higher RHR was associated with MAC incidence and AVC progression, independent of traditional CVD risk factors. Future studies are needed to determine whether modification of RHR through lifestyle or pharmacologic interventions can reduce valvular calcium incidence or progression.

Role of Imaging in Transcatheter Aortic Valve Replacement

OPINION STATEMENT

Transcatheter aortic valve replacement (TAVR) has emerged as an effective treatment alternative in patients with severe aortic stenosis (AS) who are deemed surgically high-risk or ineligible for surgery. Pre-procedural imaging, in particular computed tomography (CT), plays an integral part in the planning and performance of TAVR and is crucial for a successful treatment. Novel technological advances in CT include high-pitch, low kV acquisitions, and iterative reconstruction resulting in high image quality at substantially reduced scan duration, contrast volume, and radiation exposure. Given the high spatial and temporal resolution of the acquisitions, CT angiography provides critical information on the eligibility for the peripheral vascular access, aortic root assessment, as well as the aortic annulus measurements, including the coronary ostia and concomitant cardiac pathology. Pre-procedural CT imaging is key for appropriate device size selection to minimize peri-procedural complications and optimize procedural success. In this article, we review the current state of imaging in the pre-interventional setting of TAVR with a special emphasis on CT.