Complex Atheromatous Plaques in the Descending Aorta and the Risk of Stroke

Abstract

This meta-analysis has adopted the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines for systematic Background and Purpose-Proximal aortic plaques, especially in the aortic arch, have already been established as an important cause of stroke and peripheral embolism. However, aortic plaques situated in the descending thoracic aorta have recently been postulated as a potential embolic source in patients with cryptogenic cerebral infarction through retrograde aortic flow. The aim of the present study was to evaluate the potential association of descending aorta atheromatosis with cerebral ischemia. Methods-We conducted a systematic review and meta-analysis of all available prospective observational studies reporting the prevalence of complex atheromatous plaques in the descending aorta in patients with stroke and in unselected populations undergoing examination with transesophageal echocardiography. Results-We identified 11 eligible studies including a total of 4000 patients (667 patients with stroke and 3333 unselected individuals; mean age, 65 years; 55% men). On baseline transesophageal echocardiograpic examination, the prevalence of complex atheromatous plaques in the descending aorta was higher (P=0.001) in patients with stroke (25.4%; 95% confidence interval, 14.6-40.4%) compared with unselected individuals (6.1%; 95% confidence interval, 3.4-10%). However, no significant difference (P=0.059) in the prevalence of complex atheromatous plaques in the descending aorta was found between patients with cryptogenic (21.8%; 95% confidence interval, 17.5-26.9%) and unclassified (28.3%; 95% confidence interval, 23.9-33.1%) cerebral infarction. Conclusions-Our findings indicate that the presence of complex plaques in the descending aorta is presumably a marker of generalized atherosclerosis and high vascular risk. The present analyses do not provide any further evidence for a direct causal relationship between descending aorta atherosclerosis and cerebral embolism. (Stroke. 2014;45:1764-1770.)

Letter by Wehrum and Harloff Regarding Article, “Complex Atheromatous Plaques in the Descending Aorta and the Risk of Stroke: A Systematic Review and Meta-Analysis”

“…With great interest, we read the meta-analysis on complex atheromatous plaques in the descending aorta (DAo) and the risk of stroke by Katsanos et al 1 By analyzing 4000 patients of 11 prospective observational studies, they have shown that such atheroma are 4× more prevalent in patients with stroke undergoing transesophageal echocardiography compared with unselected patients who undergo transesophageal echocardiography for other reasons. Among patients with stroke, those with cryptogenic stroke tended to have a lower prevalence of complex plaques in the DAo compared with patients with unclassified stroke pathogenesis.…”

“…Among patients with stroke, those with cryptogenic stroke tended to have a lower prevalence of complex plaques in the DAo compared with patients with unclassified stroke pathogenesis. Katsanos et al 1 conclude that the presence of complex plaques in the DAo is presumably a marker of generalized atherosclerosis and high vascular risk and that such atheroma are not causally related with cerebral embolism.…”

Response to Letter Regarding Article, “Complex Atheromatous Plaques in the Descending Aorta and the Risk of Stroke: A Systematic Review and Meta-Analysis”

“…2 We acknowledge that the 2 studies from the research group of Harloff et al 3,4 were not included in our meta-analysis because of the restriction of our inclusion criteria in prospective cohort studies that reported the prevalence of complex atheromatous plaques in the descending aorta (DAo) using the widely available and the (still considered) gold standard investigation of transesophageal echocardiography.2 The aforementioned studies 3,4 used sophisticated MRI protocols to detect plaques and further analyze blood flow in the DAo, reporting considerably higher complex athoromatous rates in the DAo (43.6% and 52.4%, respectively) 3,4 compared with the studies presented in the meta-analysis that used protocols more close to everyday clinical practice.2 The results of these pioneering studies were, however, mentioned in the introduction (reference 6) and in the discussion section of our article (reference 29), whereas a previous study published from the same group-which reported data on the prevalence of complex DAo plaques in transesophageal echocardiographic examination-was used in the quantitative synthesis (reference 15).2 Drs Wehrum and Harloff 1 indicate that in the pivotal French study, the crude odds ratio (OR) for stroke was ≈4× greater for plaques ≥4 mm located in the distal arch/proximal DAo (crude OR, 5.5; 95% confidence interval, 2.8-10.6) compared with those located in the distal straight segment of the DAo (crude OR, 1.5; 95% confidence interval, 0.5-4.8).5 However, we note that in the same study the likelihood of cerebral ischemia was considerably higher for plaques ≥4 mm located in the ascending aorta or proximal arch (crude OR, 13.8; 95% confidence interval, 5.2-36.1) in comparison with plaques located in the distal arch/proximal DAo. In addition, the authors have provided adjusted OR according to the cause of stroke only for the ascending aorta or proximal arch plaques.…”

“…2 We acknowledge that the 2 studies from the research group of Harloff et al 3,4 were not included in our meta-analysis because of the restriction of our inclusion criteria in prospective cohort studies that reported the prevalence of complex atheromatous plaques in the descending aorta (DAo) using the widely available and the (still considered) gold standard investigation of transesophageal echocardiography.…”

“…2 The aforementioned studies 3,4 used sophisticated MRI protocols to detect plaques and further analyze blood flow in the DAo, reporting considerably higher complex athoromatous rates in the DAo (43.6% and 52.4%, respectively) 3,4 compared with the studies presented in the meta-analysis that used protocols more close to everyday clinical practice. 2 The results of these pioneering studies were, however, mentioned in the introduction (reference 6) and in the discussion section of our article (reference 29), whereas a previous study published from the same group-which reported data on the prevalence of complex DAo plaques in transesophageal echocardiographic examination-was used in the quantitative synthesis (reference 15).…”