Relation between mitral annular calcium and complex aortic atheroma in patients with cerebral ischemia referred for transesophageal echocardiography.

Mitral annular calcium (MAC) has been shown to be an independent predictor of stroke, but the basis for this association remains incompletely defined. This study was conducted to investigate the extent to which aortogenic embolism may mediate the MAC-stroke relation. In a cross-sectional study of patients referred for transesophageal echocardiography for the evaluation of cerebral ischemia, the relation between MAC and proximal and distal complex aortic atheroma (CAA) was assessed. In 419 patients composing the study cohort, MAC was associated with atherosclerosis risk factors, previous cardiovascular disease, atrial fibrillation, ipsilateral large-artery stenosis, left-sided cardiac abnormalities, and aortic valve calcium. MAC was associated with CAA of the proximal and distal thoracic aorta in unadjusted analyses, and these associations became stronger with increasing MAC severity. After adjustment for clinical and echocardiographic covariates, MAC exhibited a significant association with proximal and distal CAA in the entire cohort. In patients without alternative potential mechanisms for cerebral ischemia, however, the relation with proximal CAA became more pronounced (adjusted odds ratio 2.74, 95% confidence interval 1.22 to 6.16), but that for distal CAA changed little and became nonsignificant (adjusted odds ratio 1.97, 95% confidence interval 0.87 to 4.45). In conclusion, MAC was significantly associated with proximal and distal CAA independent of clinical and echocardiographic covariates in this cohort with cerebral ischemia, but in subjects without identifiable alternative mechanisms, the magnitude of the relation increased only for proximal CAA. These findings support the role of proximal CAA as a direct mediator of the increased stroke risk associated with MAC.

Effect of treatment on the incidence of stroke and other emboli in 519 patients with severe thoracic aortic plaque.

Severe aortic plaques seen on transesophageal echocardiography (TEE) are a high-risk cause of stroke and peripheral embolization. Evidence to guide therapy is lacking. Retrospective information was obtained regarding the occurrence of embolic events (stroke, transient ischemic attacks, or peripheral emboli) in 519 patients with severe thoracic aortic plaque seen on TEE since 1988. Treatment with statins, warfarin, or antiplatelet medications was noted. Treatment was not randomized. In a matched-paired analysis, each patient taking each class of therapy was matched for age, gender, previous embolic event, hypertension, diabetes, congestive failure, and atrial fibrillation to someone not taking that medication. Multivariate analysis was also performed. An embolic event occurred in 111 patients (21%). Multivariate analysis showed that statin use was independently protective against recurrent events (p = 0.0001). Matched analysis also showed a protective effect of statins (p = 0.0004; absolute risk reduction 17%, relative risk reduction 59%, number needed to treat [n = 6]). No protective effect was found for warfarin or antiplatelet drugs. The odds ratio for embolic events was 0.3 (95% confidence interval [CI] 0.2 to 0.6) for statin therapy, 0.7 (95% CI 0.4 to 1.2) for warfarin, and 1.4 (95% CI 0.8 to 2.4) for antiplatelet agents. Thus, there is a protective effect of statin therapy, and no significant benefit of warfarin or antiplatelet drugs on the incidence of stroke and other embolic events in patients with severe thoracic aortic plaque on TEE.