***TASK*** the task is to summarize an input biomedical literature in six sentences 
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    Input: Background —Mitral annular calcification ( MAC ) has been associated with stroke in longitudinal , community-based cohorts and cardiovascular disease ( CVD ) outcomes in many small retrospective studies . Prospect i ve data are limited on the relation of MAC with CVD morbidity and mortality . Methods and Results —We examined the association between MAC assessed by M-mode echocardiography and the incidence of CVD , CVD death , and all-cause death over 16 years of follow-up in the Framingham Heart Study subjects who attended a routine examination between 1979 and 1981 . Cox proportional hazards models were used to estimate hazard ratios ( HRs ) associated with the presence of MAC for each outcome . Of 1197(445 male , 752 female ) subjects who had adequate echocardiographic assessment , 14 % had MAC . There were 307 incident CVD events and 621 deaths . In multivariable adjusted analyses , MAC was associated with an increased risk of incident CVD ( HR , 1.5 ; 95 % CI , 1.1 , 2.0 ) , CVD death ( HR , 1.6 ; 95 % CI , 1.1 , 2.3 ) , and all-cause death ( HR , 1.3 ; 95 % CI , 1.04 , 1.6 ) . For each 1-mm increase in MAC , the risk of incident CVD , CVD death , and all-cause death increased by ≈10 % . Conclusions —The independent association of MAC with incident CVD and CVD death underscores that cardiac calcification is a marker of increased CVD risk BACKGROUND Rheumatoid arthritis ( RA ) is a systemic disease involving many organ systems and is frequently accompanied by cardiac alterations . However , there is considerable disagreement concerning the cardiac abnormalities found in patients with RA . The purpose of our investigation was to determine , by a non-invasive method such as echocardiography , the nature and extent of cardiac involvement in RA patients with no symptoms of cardiac disease , in comparison with a control sample . METHODS We selected 35 patients affected by rheumatoid arthritis ( five men , 30 women ) , aged 51 + /- 11 years . No patient had either symptoms of cardiac disease or extra cardiac complaint . As a control group we studied 52 volunteers , aged 51 + /- 12 years , r and omly selected among a larger group of subjects with no symptoms , signs and /or clinical findings of extra cardiac diseases . All were in sinus rhythm and without any cardiac symptom .  St and ard two-dimensional , M-mode and Doppler echocardiographic examination was carried out on each subject . RESULTS In RA patients we found a higher prevalence of several abnormalities . We found no statistically significant differences between the groups of RA patients based on the stage and duration of disease . We found no correlation between cardiac abnormalities and inflammatory indices or drug therapy . DISCUSSION At least three alterations seem to be typical of RA patients in the absence of any symptom of cardiac disease : ( 1 ) posterior pericardial effusion , ( 2 ) aortic root alterations and ( 3 ) valvular thickening . The prevalence of MVP is controversial and needs further investigation . These alterations are variously combined in each patient , and for this reason we think that it is possible to represent such a heart involvement as ' silent rheumatoid heart disease ' . Moreover the knowledge of the presence of unrecognised cardiac abnormalities can be very important for the correct assessment and management of the RA patient Since heart lesions were found at autopsy in 55 - 60 % of rheumatoid arthritis patients , we decided to assess echocardiographically their clinical significance . The study comprised 100 consecutive patients with rheumatoid arthritis ( 77 females and 23 males ) of the mean age 55.7 + /- 12.5 yrs ( range 18 - 83 yrs ) and the disease duration of 8.3 + /- 8.0 yrs ( range 1 - 35 yrs ) . The control group consisted of 100 consecutive age and sex matched patients admitted to university hospital . All the patients underwent echocardiographic examinations in apical and parasternal projections . The activity of the rheumatoid process , the severity of articular lesions , the presence of extraarticular sings as well as HLA DR and DQ antigens were determined clinical ly and with laboratory tests . Twenty six patients with rheumatoid arthritis had pericardial effusion , 10 revealed the sings of chronic pericarditis , in the control group 4 and 0 respectively ( p = 0.001 and p = 0.025 ) . No difference was shown in the wall contractions disturbances , size of the cardiac cavity , or thicknesses of the interventricular septum or posterior wall . In 3 rheumatoid arthritis patients , a valvular heart disease was diagnosed , this number was not significantly different from that in the control group ( 2 patients ) . There was no correlation between the lesions observed in the heart and the rheumatoid process activity estimated with clinical and laboratory indices A clinical and echocardiographic study was carried out in a r and omly selected group of 101 patients with rheumatoid arthritis to determine the prevalence of cardiac abnormalities . Adequate two-dimensional assessment s were obtained in 84 patients and 77 patients had adequate M mode recordings . Thirty-one patients ( 37 per cent ) had 45 echocardiographic abnormalities .  Five patients ( 6 per cent ) had a pericardial effusion . Eleven abnormalities of the mitral valve were noted in 10 patients ( 13 per cent ) . Three patients had mitral valve prolapse , one patient with aortic incompetence had flutter on the mitral valve , five patients had mitral annular calcium and one patient had hypertrophic obstructive cardiomyopathy and mitral annular calcification . A reduction in the E-F slope was noted in 12 patients , seven of whom had associated cardiac disease , one patient had a sinus tachycardia and four patients ( 5 per cent ) had a mild reduction without any other cardiac abnormality . Apart from the presence of pericardial effusion in 6 per cent and minor abnormalities of the E-F slope in 5 per cent of patients , all the other significant echocardiographic abnormalities could be related to the presence of associated cardiac disease Abstract Echocardiographic examination and 24-h electrocardiographic Holter monitoring were carried out on 35 patients with nodular rheumatoid arthritis ( RA ) and 35 with non-nodular RA , who were matched with the nodular RA group regarding age , sex and BSA . A further 35 patients with osteoarthrosis and spondyloarthrosis matched , with both RA groups , constituted a control group . Patients with a history of myocardial infa rct ion , hypertension , rheumatic fever and diabetes were excluded from the study .  Cardiac involvement , evaluated using  echo-Doppler cardiography , 24-h electrocardiographic Holter monitoring and ECG at rest  , occurred in 25 ( 71.9 % ) patients with nodular RA and in 15 ( 42.9 % ) with non-nodular RA in comparison to 8 ( 22.9 % ) control group patients ( P<0.0002 ) .  Holter electrocardiographic monitoring  over 24 h did not present any essential differences in frequency of rhythm disorders between the examined groups and the control group . However , it revealed more patients with 1-mm ST depression in the nodular RA group than in the non-nodular and control groups . Echocardiographic examination revealed more cases of valvular heart abnormalities , especially those of mitral insufficiency , in nodular RA patients than in non-nodular and control patients . Both a mitral valve prolapse and a pericardial effusion were noted in 8.6 % of nodular RA patients . Patients with nodular RA were noted to have a bigger aortic root diameter , but smaller ejection fraction , mean velocity of circumferential fibre shortening and fractional shortening in comparison to non-nodular and to control group patients In the elderly , mitral annular calcification ( MAC ) and aortic valve sclerosis ( AVS ) are associated with increased cardiovascular morbidity and mortality .  Aortic annular calcification ( AAC ) commonly occurs with MAC . However , the prognostic value of AAC , singly or in combination with MAC and AVS , for incident cardiovascular disease and mortality is unknown . From the Cardiovascular Health Study , we analyzed 3,782 participants ( 76 + /- 5 years of age , 60 % women ) who had an echocardiogram at the 1994 to 1995 examination and who were prospect ively followed for an average of 6.6 years ( range 0.01 to 8.5 ) . All 3 calcification categories were associated with incident congestive heart failure ( MAC : hazard ratio [ HR ] 1.71 , 95 % confidence interval [ CI ] 1.35 to 2.18 , AAC : HR 1.62 , 95 % CI 1.28 to 2.06 , and AVS : HR 1.50 , 95 % CI 1.19 to 1.89 ) and death . A stronger association with incident cardiovascular disease and mortality was observed with a larger number of calcification categories and with increased MAC severity . Moreover , in the participants with prevalent cardiovascular disease at echocardiographic examination ( n = 1,054 ) , MAC and AAC were still associated with cardiovascular mortality ( MAC : HR 1.91 , 95 % CI 1.04 to 3.50 ; AAC : HR 2.11 , 95 % CI 1.16 to 3.85 ) even in fully adjusted models . In conclusion , MAC , AAC , and AVS are associated with a significant risk of incident congestive heart failure , cardiovascular and all-cause mortalities , and worse outcome in older patients with preexisting cardiovascular disease . Elderly patients with these findings represent a high-risk group and may require close medical attention 
    Output:
    
Our systematic review pointed out the strength and the grade of both pericardial and cardiac valvular involvement in RA patients .