Retinal microvascular changes in microvascular angina: Findings from the Australian Heart Eye Study.

OBJECTIVE: Microvascular changes in microvascular angina are poorly understood due to difficulties in imaging the coronary microcirculation in vivo. The retinal microvasculature may reflect changes in coronary microcirculation. We assessed microvascular changes in the retina in patients with microvascular angina and compared them with patients with angiographically proven coronary artery disease. METHODS: We performed retinal photography and coronary angiography on 915 patients. Retinal vessel calibers were measured using a validated computer-assisted method; coronary artery disease was graded from coronary angiograms. Microvascular angina was defined as angina with <25% stenosis in all coronary epicardial arteries. RESULTS: A total of 139 patients (15.2%) had microvascular angina, while 776 (84.8%) had coronary artery disease. Participants with microvascular angina and coronary artery disease had similar retinal arteriolar and venular calibers. After adjustment for age, ethnicity, mean arterial pressure, diabetes, current smoking, body mass index, and fellow vessel caliber, women with smaller venules were threefold more likely to have microvascular angina than women with larger venules (multivariable-adjusted odds ratio 3.54, 95% confidence interval 1.35 to 9.24, P < 0.01). This difference was not observed in men. CONCLUSIONS: Microvascular angina in women was associated with microvascular changes distinct from those in coronary artery disease.

Association between Retinal Arteriolar and Venule Calibre with Prevalent Heart Failure: A Cross-Sectional Study.

BACKGROUND: There is evidence to suggest that microvascular disease, particularly diabetic retinopathy, plays a role in the pathogenesis of HF. However, whether changes in retinal vessel calibre predicts HF is unclear. The purpose of this study was to examine the association of retinal microvascular structure with prevalent heart failure (HF). METHODS: The Australian Heart Eye Study (AHES) is a cross-sectional study that surveyed 1680 participants who presented to a tertiary referral hospital for the evaluation of potential coronary artery disease by coronary angiography. Retinal vessel calibre was graded using retinal photography and participants' self-reported echocardiography-confirmed HF was obtained via an extensive medical questionnaire. RESULTS: There were 107 participants (8.1%) with prevalent self-reported HF. Persons with wider retinal arteriolar calibre (comparing highest versus lowest tertile or reference) were more likely to have prevalent HF (OR 3.5; 95% CI, 1.7-7.2) when adjusted for age and sex. After further adjustment for body mass index, hypertension, diabetes, smoking status, triglycerides and estimated glomerular filtration rate, this association remained significant (OR 4.5; 95% CI, 2.0-9.8). After further stratification, this association remained significant among participants with diabetes (OR 10.3; 95% CI, 2.7-39.3) but not in those without diabetes (OR 2.7; 95% CI, 0.9-7.5). The strength of this association was not dependent on the length of history of diabetes, or retinopathy status. There was no significant association between retinal venular calibre and prevalence of HF. CONCLUSIONS: Wider retinal arteriolar diameter was significantly and independently associated with prevalent HF in participants of a cross-sectional study. This association was significant stronger among participants with diabetes compared to without diabetes. No association was found between retinal venule calibre with prevalent HF.

Gender differences in the severity and extent of coronary artery disease.

OBJECTIVE: To investigate whether women presenting with suspected angina would show less severe coronary artery disease in than men as determined by the extent score. METHODS: We examined 994 participants of the Australian Heart Eye Study presenting for coronary angiography in the investigation of chest pain from June 2009 to February 2012. People were excluded if there was a history of coronary artery bypass surgery, previous stenting procedure or incomplete angiogram scoring. An extent and vessel score was calculated using invasive coronary angiography. Normal coronary arteries were defined as having no luminal irregularity (Extent score = 0). Obstructive coronary artery disease was defined as a luminal narrowing of greater than 50%. RESULTS: Women compared to men without infarction had a lower burden of CAD with up to 50% having normal coronary arteries in the 30-44 year group and 40% in the 45-59 year group. Compared to men, women with chest pain had lower mean extent scores (19.6 vs 36.8; P < 0.0001) and lower vessel scores (0.7 v 1.3; P < 0.0001). Although the mean extent score was lower in women than men with myocardial infarction, this was not statistically significant (34.8 vs 41.6 respectively; P = 0.18). CONCLUSION: There is a marked difference in coronary artery disease severity and burden between females and males presenting for the investigation of suspected angina. Women are more likely to have normal coronary arteries or less severe disease than age-matched men, particularly if they do not present with myocardial infarction.