Frequency of thromboembolic stroke in persons greater than or equal to 60 years of age with extracranial carotid arterial disease and/or mitral annular calcium

Prognostic value of mitral annular calcification in coronary atherosclerotic disease assessed by coronary computed tomographic angiography

Background

There is a lack of evidence on the link between mitral annular calcification (MAC) and coronary atherosclerotic diseases. The present investigation was undertaken to detect the clinical and prognostic value of MAC in coronary atherosclerotic diseases in patients who underwent coronary computed tomographic (CT) angiography.

Materials and Methods

Two hundred and five individuals with MAC and without it (n = 85 and 120, respectively) were included in the present cross-sectional study. Coronary artery disease-reporting and data system (CAD-RADS) at coronary CT angiography was used to define the severity of coronary atherosclerotic diseases. Patients were classified into no or non-significant CAD (CAD-RADS 0-2) and significant CAD (CAD-RADS 3-5) according to the severity of coronary atherosclerotic diseases. The association of MAC with two mentioned groups (no or non-significant CAD and significant CAD) was assessed using the Chi-squared test and logistic regression in crude and adjusted models.

Results

Patients with MAC were significantly older (69.34 ± 8.20 vs. 60.64 ± 11.42, P < 0.001), had lower glomerular infiltration rate (69.67 ± 20.92 vs. 78.00 ± 20.23, P = 0.005), and higher coronary artery calcification score (352.87 ± 495.85 vs. 200.55 ± 426.13, P = 0.05) in comparison to those without MAC. However, the significant difference between the two groups regarding coronary artery calcification score disappeared after adjustment for confounders (P = 0.14). In addition, a statistically significant positive link between MAC and significant CAD was observed (odds ratio [OR] [95% confidence interval (CI)]: 1.96 [1.04-3.71], P = 0.04). Nevertheless, the association became statistically insignificant after adjustment for confounders (OR [95% CI]: 1.60 [0.78-3.28], P = 0.2).

Conclusion

The findings of the study revealed that MAC has no independent prognostic value in coronary atherosclerotic diseases evaluated by coronary CT angiography.

Risk of Cerebral Embolization with Caseous Calcification of the Mitral Annulus: Review Article

Background:

Caseous calcification of the mitral annulus (CCMA) is believed to have a benign prognosis. Several authors have recommended conservative management in asymptomatic patients. However, the prevalence of cerebrovascular events (CVE) in patients with CCMA has never been evaluated before. The aims of this study are to investigate whether patients with CCMA are at increased risk of cerebral embolization, and to determine whether elective surgical resection of CCMA should be considered to prevent a cardioembolic stroke.

Methods:

A comprehensive literature search was obtained from MEDLINE via PubMed.gov, ScienceDirect.com, and Google Scholar using the following search queries: caseous calcification of the mitral annulus, intracardiac pseudotumor, mitral annular calcification, and cardioembolic stroke.

Results:

From our initial search that yielded 1,502 articles, we identified a total of 130 patients with CCMA reported in 86 publications. Literature review revealed that the prevalence of CVE associated with CCMA is 19.2% (25 of 130) which is significantly higher than the prevalence of CVE reported with mitral annular calcification (MAC), 11.8% (214 of 1818) (range 4.8% to 24.1%) (P = 0.01796) (odds ratio = 1.78; 0.95 confidence interval = 1.1278 – 2.8239). Only four of 25 (16.0%) patients with CCMA who suffered a CVE had history of atrial fibrillation (AF).

Conclusion:

Based on our review, it would be reasonable to consider elective surgical resection of CCMA in asymptomatic patients who are good surgical candidates, because patients with CCMA may be at increased risk of embolic strokes, which are unrelated to AF.

Interactions between cardiovascular and cerebrovascular disease

OPININION STATEMENT: All patients with ischemic stroke should undergo a comprehensive assessment of cardiovascular risk. Patients with carotid artery disease, symptoms of cerebral ischemia and high cardiovascular risk profiles should be considered for noninvasive testing for coronary artery disease (CAD). Routine testing for CAD before carotid endarterctomy is not recommended. Patients with coexisting coronary and carotid artery disease should be more aggressively treated for reducing their "very high" risk of cardiovascular events. In patients candidates to carotid revascularization, a preoperative coronary angiography and coronary revascularization are not recommended. Warfarin is recommended in all patients with moderate to high risk of stroke. Novel oral anticoagulants represent an attractive alternative to warfarin. However, their place in therapy in clinical practice is not yet established. Percutaneous closure of the left atrial appendage for stroke prophylaxis may be considered in selected patients with atrial fibrillation and contraindications for oral anticoagulant therapy. Warfarin is not indicated in patients with heart failure who are in sinus rhythm. Percutaneous closure of patent foramen does not seem to be superior to medical therapy for the prevention of recurrences in patients with cryptogenic stroke.

Heart disease and aging

CAD is the most common cause of death in older persons and was present in 43% of 1,160 men and in 41% of 2,464 women, mean age 81 years. Hypertension was present in 60% of these older women and in 57% of these older men. The prevalence of valvular aortic stenosis, aortic regurgitation, mitral regurgitation, and MAC increases with age in older men and in older women. The prevalence and incidence of CHF increase with age. CHF is the most common cause of hospitalization in persons aged 65 years and older. The prevalence of normal LV ejection fraction associated with CHF increases with age and is higher in older women than in older men. The prevalence of chronic atrial fibrillation increases with age and was present in 16% of 1,160 older men and in 13% of 2,464 older women. Atrial fibrillation is an independent predictor of new coronary events and thromboembolic stroke in older persons. Older persons who have unexplained syncope should have 24-hour ambulatory electrocardiograms to determine whether pauses of longer than 3 seconds are present that require permanent pacemaker implantation.

Mitral annulus calcification--a window to diffuse atherosclerosis of the vascular system

Mitral annulus calcification (MAC) is a chronic, non-inflammatory, degenerative process of the fibrous support structure of the mitral valve. It occurs more often in women and the elderly. MAC is associated with known atherosclerotic risk factors such as diabetes mellitus, hypertension and hypercholesterolemia. It is also known that patient with MAC have higher prevalence of left atrial and left ventricular enlargement, hypertrophic cardiomyopathy, atrial fibrillation, aortic valve calcification and stenosis, various cardiac conduction defects, bacterial endocarditis, cardiovascular events and stroke, though the etiological basis is unknown. Pathological studies from the 80s present a theory that MAC is a form of atherosclerosis. In order to test this theory we conducted during the last years a few clinical studies to examine the association of MAC and known atherosclerotic phenomena. We found higher prevalence of aortic atheroma in patients with MAC and atheroma thickness. We also found in MAC patients higher prevalence of carotid artery stenosis, coronary artery stenosis, peripheral artery stenosis and higher levels of beta2-Glycoprotein I antibodies in patients with MAC thickness equal or greater than 5 mm. These studies support the theory that MAC is a form of atherosclerosis and define a group of patients with higher prevalence of atherosclerotic disease in multiple blood vessels. The purpose of this review is to summarize the data concerning MAC and atherosclerotic processes, emphasizing that MAC in itself may be an atherosclerotic process.

Association between mitral annular calcification and carotid atheroma

Carotid artery atherosclerosis is a strong predictor of stroke and represents a potential source of cerebral emboli. The aim of this study was to investigate whether an association exists between mitral annular calcification and carotid atheroma. In addition, the characteristics of carotid atheromas were compared between patients with and without mitral annular calcification. The authors found that there was a significant association between the presence of mitral annular calcification and carotid atheroma. Mitral annular calcification in the elderly may be a form of atherosclerosis.

Association between mitral annulus calcification and aortic atheroma: a prospective transesophageal echocardiographic study

BACKGROUND AND PURPOSE

Although mitral annulus calcification (MAC) has been reported to be a significant independent predictor of stroke, no causative relationship was proven. It is also known that aortic atheroma (AA), especially those >/=5 mm thick and/or protruding and/or mobile are associated with stroke. This study was designed to determine whether an association exists between MAC and AA.

METHODS

We prospectively evaluated the records of 279 consecutive patients who underwent transesophageal echocardiography (TEE) for various indications to measure the presence and characteristics of AA. The 105 patients in whom a diagnosis of MAC was made on transthoracic echocardiography (TTE) immediately preceding the TEE, were compared with 174 age-matched patients without MAC. MAC was defined as a dense, localized, highly reflective area at the base of the posterior mitral leaflet. We measured MAC thickness with two-dimensional-TTE in four-chamber view and AA thickness, protrusion and mobility with TEE. AA was defined as localized intimal thickening of >/=3 mm. A lesion was considered complex if there was plaque extending >/=5 mm into the aortic lumen and/or if it was protruding, mobile or ulcerated.

RESULTS

No differences were found between the groups in risk factors for atherosclerosis or in indications for referral for TEE. Significantly higher rates were found in the MAC group for prevalence of AA (91 vs. 44%, P<0.001), atheromas >/=5 mm thick (68 vs. 19%, P<0.001), protruding atheromas (44 vs. 15%, P<0.001), ulcerated atheromas (10 vs. 1%, P<0.001) and complex atheroma (74 vs. 22%, P<0.001). Sixty patients had MAC thickness >/=6 mm and 45<6 mm. AA thickness was significantly greater in the patients with a MAC thickness of >/=6 mm (6.1+/-2.8 vs. 5.0+/-2.6 mm, P=0.03). On multivariate analysis MAC, hypertension and age were the only independent predictors of AA (P=0.0001, 0.005 and 0.007, respectively).

CONCLUSIONS

There is a significant association between the presence and severity of MAC and AA. MAC may be an important marker for atherosclerosis of the aorta. This association may explain in part the high prevalence of systemic emboli and stroke in patients with MAC.

The older man's heart and heart disease

CAD is the most common cause of death in older men and was present in 44% of 664 men, mean age 80 years. Independent risk factors for new coronary events in older men include increasing age, prior CAD, cigarette smoking, hypertension, diabetes mellitus, high serum total cholesterol, and low serum HDL cholesterol. In older men with hypertension, echocardiographic LVH is a powerful independent predictor of new coronary events, atherothrombotic brain infarction, and CHF. In 554 older men with a mean age of 80 years, two-dimensional and Doppler echocardiography demonstrated that the prevalence of aortic stenosis was 14%, 1 + aortic regurgitation or greater was 31%, rheumatic mitral stenosis was 0.4, 1 mitral regurgitation or greater was 32%, mitral annular calcium was 35%, hypertrophic cardiomyopathy was 3%, idiopathic dilated cardiomyopathy was 1%, left atrial enlargement was 29%, LVH was 41%, and abnormal LVEF was 29%. The prevalence and incidence of CHF increase with age in older persons. The prevalence of a normal LVEF associated with CHF as a result of prior myocardial infarction or hypertension was 22% in men aged 60 to 69 years, 33% in men aged 70 to 79 years, 41% in men aged 80 to 89 years, and 47% in men aged 90 years or older.

Association of mitral annular calcium with new thromboembolic stroke at 44-month follow-up of 2,148 persons, mean age 81 years

We investigated in a prospective study of 2,148 persons (mean age 81 years), the association between mitral annular calcium and new thromboembolic stroke at 44-month follow-up. Independent risk factors for new thromboembolic stroke were prior stroke (risk ratio 2.4), mitral annular calcium (risk ratio 2.6), atrial fibrillation (risk ratio 3.0), and male gender (risk ratio 1.6).

Use of panoramic radiography among an ambulatory dental population to detect patients at risk of stroke

Panoramic radiographs of 3.6 percent of 1,175 newly accepted dental school patients displayed calcifications in the area of the carotid vasculature. The authors interviewed the patients with calcifications to determine whether they exhibited any recognized atherosclerosis, risk factors. One patient had symptoms of atherosclerosis, and a statistically significant correlation was found for obesity among the patients interviewed. The authors concluded that panoramic radiography is useful for identifying some asymptomatic patients with carotid calcifications. These patients should be referred to their physicians promptly for a cerebrovascular work-up as part of an active stroke-prevention strategy.

Thrombus associated with mitral valve calcification. A possible mechanism for embolic stroke

BACKGROUND

Several studies have demonstrated an association between mitral annular calcification and stroke; however, the pathophysiological explanation remains speculative.

CASE DESCRIPTIONS

We describe two patients with cerebral embolism in whom mitral valve calcification was demonstrated by transthoracic echocardiography. In both patients, transesophageal echocardiography identified a mass that appeared to be thrombus on the calcified portion of the mitral apparatus. There was no evidence of a hypercoagulable state or endocarditis in either case. Repeated transesophageal echocardiography after anticoagulation demonstrated resolution of the masses in both patients.

CONCLUSIONS

These cases support the hypothesis that thrombus formation may be a pathophysiological link between ischemic cerebral events and mitral annular calcification in some patients.

Usefulness of M-mode, 2-dimensional, and Doppler echocardiography in the diagnosis, prognosis, and management of valvular aortic stenosis, aortic regurgitation, and mitral annular calcium in older patients

OBJECTIVE

To review the diagnosis, prognosis, and management of valvular aortic stenosis, aortic regurgitation, and mitral annular calcium (MAC) with emphasis on older persons.

DATA SOURCES

A computer-assisted search of the English-language literature (MEDLINE database) followed by a manual search of the bibliographies of pertinent articles.

STUDY SELECTION

Studies on the diagnosis, prognosis, and management of valvular aortic stenosis, aortic regurgitation, and MAC were screened for review. Studies in older persons and recent studies were emphasized.

DATA EXTRACTION

Pertinent data were extracted from the reviewed articles. Emphasis was on studies involving older persons. Relevant articles were reviewed in depth.

DATA SYNTHESIS

Available data about the diagnosis, prognosis, and management of valvular aortic stenosis, aortic regurgitation, and MAC with emphasis on studies involving older persons were summarized.

CONCLUSIONS

Valvular aortic stenosis, aortic regurgitation, and MAC are degenerative cardiac disorders which are common in older people. The presence and severity of these cardiac disorders are diagnosed by M-mode, 2-dimensional, and Doppler echocardiography. M-mode, 2-dimensional, and Doppler echocardiographic techniques are also very useful in the prognosis and management of these cardiac disorders in older persons.