CASE 2—2012 Intraoperative Diagnosis and Management of Caseous Calcification of the Mitral Annulus

Surgical treatment of caseous calcification of the mitral annulus causing mitral stenosis and mimicking the clinical picture of infective endocarditis: A case report

Among masses involving the mitral valve and annulus, caseous calcification of the mitral annulus (CCMA) is a rare disease. CCMA accounts for .63% of all mitral annular calcification (MAC) cases. The pathophysiology is still unknown. The correct diagnosis and treatment of this disease is very important to prevent complications. We present a case of giant CCMA with advanced mitral stenosis and hypertrophic cardiomyopathy, presenting with symptoms of infection and therefore a preliminary diagnosis of infective endocarditis. Because of these features, we wanted to share our case as it is the 1st case in the literature.

The Spectrum of Caseous Mitral Annulus Calcifications

Mitral annular calcification (MAC) is a chronic, degenerative condition of the fibrous mitral annulus, which may transform to liquefaction necrosis MAC, a rare variant of caseous MAC. We present a series of experiences, showing the varying manifestations of caseous MAC according to multimodal imaging. (Level of Difficulty: Intermediate.)

Approach to An Unusual Cardiac Mass: Mitral Annulus Caseoma

Caseous calcification of the mitral annulus (CCMA) is known to be a rare variant of mitral annulus calcification, a chronic and degenerative process of the mitral valve fibrous ring. It usually carries a benign prognosis. The following case demonstrates a huge mitral annulus caseoma that complicated with severe mitral regurgitation and was treated with a successful surgery. The common consensus on the optimal management of CCMA is conservative medical management and avoiding unnecessary surgery. Therewithal, the current indications for surgical intervention include mitral valve dysfunction, strokes and uncertain diagnosis. Aggressive debridement, risk of left ventricular perforation and exposure of caseous debris to the systemic blood flow may increase the risk of a standard mitral valve surgery. Mitral valve replacement should be preferred compared with mitral valve repair.

Caseous Calcification of the Mitral Annulus

Soft-tissue masses or mass-like lesions involving the mitral valve include a wide range of diseases such as tumors, abscesses, vegetations, thrombus and, rarely, caseous calcifications of the mitral annulus. Caseous calcifications of the mitral annulus is a rare variant of mitral annular calcification that is usually asymptomatic and diagnosed incidentally. Echocardiography is the first-choice imaging modality. Cardiac computed tomography is an ideal tool to confirm the presence of calcifications and caseous necrosis. In cases where there is doubt, cardiac magnetic resonance imaging may be used. We present the case of a 62-year-old patient with an intra-cardiac mass diagnosed by echocardiography. Imaging modalities to achieve a correct diagnosis and avoid unnecessary surgical intervention are discussed.

Caseous calcification of the mitral annulus - the complementary role of computed tomography and transthoracic echocardiogram

Purpose

Caseous calcification is a relatively uncommon variant of calcification of the mitral annulus. The purpose of the study was to assess characteristic radiological features of caseous calcification of the mitral annulus (CCMA) using computed tomography (CT) and compare the usefulness of CT and transthoracic echocardiogram (TTE) in a diagnosis of CCMA.

Material and methods

Seventeen patients with CCMA, who underwent TTE and CT, were analysed. The following features of CCMA were evaluated: location, size, attenuation, enhancement after contrast administration, and margins.

Results

In all cases TTE visualised an echo-dense structure with an irregular appearance involving the mitral valve annulus. In five cases the acoustic shadowing artefact was visible, and in four cases the mass contained central areas of echolucency. Eleven patients had valve disease.

On CT CCMA appeared as a round mass in one case, in 10 cases as an oval mass, and in six patients it had a semilunar shape.

In all cases on unenhanced CT, CCMA appeared as a hyperdense mass. On enhanced CT, CCMA in 10 cases (58.8%) had a hypodense centre, and in 7seven (41.2%) it had a hyperdense centre without enhancement after contrast administration. A hyperdense rim was observed in all cases except one patient.

Conclusions

In cases of the atypical appearance of CCMA on TTE, CT can lead to a definitive diagnosis. The combination of unenhanced CT and after IV contrast administration scans allows for recognition and distinction of CCMA from other pathologies, while TTE allows for assessment of additional valve dysfunction.

Caseous Calcifications of Mitral Annulus as an Unusual Cause of Cardioembolic Stroke in a 40-Year-Old Man

Caseous calcification of mitral annulus (CCMA) is a rare variant of mitral annular calcification. Previously thought to have been a benign condition, CCMA may be a potential source of cardioembolic stroke. We present a case of a 40-year-old man with end-stage renal disease on hemodialysis and hypertension who presented with acute onset of visual blurring and headache and was diagnosed with cardioembolic stroke secondary to CCMA. It is imperative for the echocardiographers to recognize the typical features of CCMA and to differentiate it from other common causes for appropriate intervention.

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.

A 65 year-old woman with an echodense mitral annular mass

Caseous calcification of the mitral annulus (CCMA) is a rare variant of mitral annular calcification which usually represents an incidental finding during cardiac imaging. Differential diagnosis from significant lesions such as myocardial abscesses or tumours may be problematic. Herein, we present the case of a 65 year-old woman with CCMA who was managed conservatively. Besides providing useful diagnostic clues, we briefly discuss management issues for this under-recognised clinical entity.

Caseous calcification of the mitral annulus: a review

Caseous calcification of the mitral annulus (CCMA) is a rare variant of mitral annular calcification (MAC). Since most cardiologists are unfamiliar with CCMA, it is commonly misdiagnosed as an abscess, tumor or infective vegetation on the mitral valve. In most cases, conservative management for this lesion is sufficient. In this review, we will discuss the various aspects of this condition and illustrate the gross and histologic pathology as well as various imaging modalities (Ultrasound, Computed tomography, Cardiac Magnetic resonance) to assess this unusual cardiac mass.