Mitral Annular Calcification, Aortic Valve Sclerosis, and Incident Stroke in Adults Free of Clinical Cardiovascular Disease

Abstract

Background and Purpose-Mitral annular calcification (MAC) and aortic valve (AV) sclerosis have each been linked to cardiovascular disease. Whether MAC and AV sclerosis are risk factors for stroke independent of other echocardiographic or laboratory predictors has not been established. We evaluated the relationship between MAC, AV sclerosis, and first stroke events in a population-based cohort. Methods-Our study cohort consisted of 2723 American Indians participating in the Strong Heart Study who were free of prevalent cardiovascular disease. Participants underwent standardized clinical, echocardiographic, and laboratory evaluation, and incident stroke was ascertained using validated methods. Results-During a median follow-up of 7 years, 86 strokes occurred. Age-and sex-adjusted incidence rates of stroke were significantly increased for MAC (rate ratio [RR], 3.12; 95% CI, 1.77 to 5.25) but not for AV sclerosis (RR, 1.15; 95% CI, 0.45 to 2.49). MAC was also associated with a reduced time to first stroke events after adjustment for clinical variables and the inflammatory markers C-reactive protein and fibrinogen (hazard ratio [HR], 2.42; 95% CI, 1.39 to 4.21) or the echocardiographic covariates left ventricular hypertrophy and left atrial enlargement (HR, 1.89; 95% CI, 1.04 to 3.41). Individuals with and without AV sclerosis showed no significant difference in stroke-free survival in unadjusted analyses (Pϭ0.698). Crossing of the survival curves precluded multivariable analysis using Cox models. Conclusions-In this cohort of American Indians without clinical cardiovascular disease, the presence of MAC, but not AV sclerosis, proved to be a strong risk factor for incident stroke after extensive adjustment for other predictors. Individuals exhibiting MAC may benefit from aggressive risk factor modification, but this will require further investigation. (Stroke. 2005;36:2533-2537.)Key Words: calcium Ⅲ echocardiography Ⅲ heart valves Ⅲ stroke M itral annular calcification (MAC) is characterized by calcium and lipid deposition in the annular fibrosa of the mitral valve, whereas aortic valve (AV) sclerosis results from similar accumulation involving the AV leaflets. 1 Clinical precursors of atherosclerosis are also risk factors for MAC and AV sclerosis, 2,3 and the 2 conditions often exist concurrently. 2 Each, in turn, has been documented to be an independent predictor of cardiovascular events. 4,5 Several, 6,7 although not all, 8,9 studies have detailed a similar relationship between MAC and stroke, but an independent association between AV calcification and cerebral infarction has only been demonstrated in the presence of AV stenosis. 5,10,11 MAC and AV sclerosis are associated with atherosclerosis risk factors that can promote left ventricular (LV) hypertrophy and left atrial (LA) enlargement, each of which has been reported to predict cerebrovascular events. 12,13 However, available studies linking valvular calcification with cerebral ischemia have adjusted only partly, if at all, for these concurrent echocardiographi...

The Association of Thyroid Function and Heart Valve Sclerosis. Results from a Population-Based Study

“…We assume that our results may reflect an association between thyroid function and atherosclerotic state in male individuals with high TSH levels, taking into account that AVS and MAC both share common risk factors of atherosclerosis [1,2,4,6], and are highly associated with generalized atherosclerosis [6], coronary artery disease [16,17], myocardial infarction [5], and stroke [4]. In particular MAC is strongly associated with cardiovascular disease [12,18].…”

“…Pathohistologically, early lesions represent the summation of degenerative and inflammatory processes that are similar to the development of atherosclerosis, resemble atherosclerotic plaques, and are characterized by lipid and calcium deposition in the valve annular fibrosa [3]. Thus, AVS and MAC are independently associated with atherosclerotic diseases [2,[4][5][6].…”

Factors Associated with Incident Ischemic Stroke in Hospitalized Heart Failure Patients: A Pilot Study

“…Our finding of BNP as a risk factor for stroke also has not been reported before. Cardiomyopathy and valvular heart disease can be risk factors for stroke in cardiac diseases (8,17). However, these two were not present in the stroke group.…”

Aortic Valve Calcification and Risk of Stroke

“…[1][2][3][4] Remarkably, data on AVC and risk of incident stroke have been less unambiguous. 5,6 Previous populationbased studies demonstrated substantial variations in risk estimates, 1,2,4 with HRs ranging from 1.09 to 1.38.…”

“…[1][2][3][4] Interestingly, knowledge on the relation of AVC with subsequent risk of stroke remains uncertain, 5,6 because of limited and conflicting data. Yet, as potential source of cardioembolism 7 and its relatively high prevalence in the general population of ≥60 years, 4,8 further evaluation of AVC in relation with future stroke is warranted.…”