Choroidal Thickness (CTh) Patterns in Patients with Coronary Artery Disease (CAD)

Abstract

Purpose : Subfoveal choroidal thinning has been shown to occur in cases of systemic vascular disease such as carotid artery stenosis, hypertension, and heart failure; however, few studies in this population have investigated CTh at points outside the fovea. We performed a cross-sectional clinical study of CTh measured at 5 points in the macula in patients with CAD compared to controls without CAD, testing the hypothesis that patients with CAD would exhibit choroidal thinning at all points compared to controls.

Methods : 36 patients (70 eyes) with documented CAD and 28 controls (56 eyes) underwent enhanced depth imaging spectral domain optical coherence tomography (EDI SD-OCT) at a single large city hospital. Patients were defined as having CAD if they had >50% obstruction in at least 1 coronary artery, positive stress test, history of ST elevation myocardial infarction, or revascularization procedure; controls had no self-reported history of cardiac disease or diabetes. Images were analyzed for subfoveal CTh and CTh 2000 µm superiorly, inferiorly, nasally, and temporally to the fovea by 2 trained readers. An intraclass correlation coefficient (ICC) was used to measure agreement between the readers, and their results were averaged. CTh’s at each point were compared using a student’s t-test.

Results : There was no difference in age between subjects with CAD and healthy controls (P=0.53). All 5 CTh measurements were significantly lower in patients with CAD compared to controls (P<0.001), with mean differences ranging from 51.7 to 66.8 µm (Table 1). Within the CAD population, CTh was significantly lower temporally (P<0.001) and nasally (P<0.001) than subfoveally, consistent with the pattern observed in our control population and other healthy populations. Furthermore, the absolute difference between subfoveal and nasal CTh and between subfoveal and temporal CTh did not vary significantly between patients with CAD and controls (P=1.00 and P=0.89, respectively). ICC between the 2 readers was 0.945.

Conclusions : Patients with CAD show overall thinning of the choroid throughout the macula, with preservation of the normal spatial CTh pattern. These findings are of interest because choroidal thinning has been associated with high-risk phenotypes of age-related macular degeneration such as reticular pseudodrusen, the primary structural feature of reticular macular disease.

This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.

 

Figure 1: CTh pattern in CAD Group vs. Non-CAD Group