Evaluation of the relationship between coronary artery disease and retinal vascular density using optical coherence tomography angiography

In this study it was aimed to establish a relationship between patients who underwent coronary angiography (CAG) with the suspicion of coronary artery disease (CAD) by determining the severity of CAD with the Gensini score and evaluating the microvascular changes in both CAD and CAD severity and retinal superficial capillary plexus (SCP) with optical coherence tomography angiography (OCTA). Between August 1, 2021 and October 31, 2022, 120 eyes of 60 patients with coronary artery disease (CAD) who presented with chest pain to the Cardiology Department's clinic and underwent coronary angiography (CAG) with a diagnosis of stable angina pectoris (SAP) and 117 eyes of 59 patients with normal coronary artery structure were included in the study. The data of the patients included in the study, such as their coronary angiography (CAG) data, demographic characteristics, left ventricular ejection fraction (LVEF), comorbid diseases and laboratory results were retrospectively reviewed. In 3x3 mm optical coherence tomography angiography (OCTA) scans, the vascular density (VD) of the superficial capillary plexus (SCP) in different quadrants in the foveal and parafoveal regions, the vascular perfusion percentage (VP) and the width, area, and perfusion rate of the foveal avascular zone (FAZ) were separately scanned and recorded. Coronary artery disease (CAD) (n=60) and Control (n=59) groups were established. When comparing VD (vascular density) parameters between the coronary artery disease (CAD) and control groups, there was a statistically significant decrease in the full, nasal, temporal, and inferior VD parameters in the CAD group (p=0.023, p=0.034, p=0.045, p=0.027 respectively). When VP (vascular perfusion) parameters were compared there was a statistically significant decrease in the inner, full, nasal, temporal, and inferior VP parameters in the CAD group (p=0.039, p=0.029, p=0.042, p=0.034, p=0.041 respectively). There was no significant difference between the two groups in FAZ (foveal avascular zone) parameters such as area, perimeter and circularity (p=0.956, p=0.671, p=0.895 respectively). In the control group, when attempting to establish a relationship between LVEF (left ventricular ejection fraction) and VD (vascular density) a significant positive correlation was found between VD central, inner, full, nasal, temporal, superior and inferior parameters (p=0.005, p<0.0001, p<0.0001, p=0.001, p<0.0001, p=0.007, p=0.007 respectively). In the control group, when attempting to establish a relationship between LVEF and VP (vascular perfusion), a significant positive correlation was found between VP central, inner, full, nasal, temporal, superior, and inferior parameters (p=0.010, p<0.0001, p=0.001, p<0.0001, p=0.015, p=0.009, p=0.002 respectively). In the CAD group, when attempting to establish a relationship between LVEF and VD, a significant positive correlation was found between VD central, inner, full, and inferior parameters (p=0.002, p=0.001, p=0.016, p=0.002 respectively). In the CAD group, when attempting to establish a relationship between LVEF and VP, a significant positive correlation was found between VP central, inner, full, nasal, temporal, superior, and inferior parameters (p<0.0001, p=0.001, p=0.001, p=0.041, p=0.011, p=0.004, p=0.022 respectively). In the CAD group, when attempting to establish a relationship between the Gensini score and VD, a significant negative correlation was found between VD inner, full, nasal, temporal, superior, and inferior parameters (p<0.0001, p<0.0001, p=0.020, p=0.001, p=0.002, p=0.002 respectively). In the CAD group, when attempting to establish a relationship between the Gensini score and VP, a significant negative correlation was found between VP inner, full, nasal, temporal, superior, and inferior parameters (p=0.009, p=0.005, p=0.029, p<0.0001, p=0.001, p=0.001 respectively). In light of this study and future research, the investigation and diagnosis of retinal vascular diseases in patients diagnosed with CAD (coronary artery disease) and HF (heart failure) can be conducted noninvasively, quickly and practically through OCTA (optical coherence tomography angiography). This will aid in early diagnosis and treatment helping to prevent the reduction or loss of vision. Moreover, coronary artery disease is a common condition in society and one of the leading causes of mortality. The detection of a decrease in retinal VD (vascular density) and VP (vascular perfusion) by OCTA may facilitate the early detection of narrowing in the coronary arteries and HF, which are structurally similar. Hence, it is concluded that this could be beneficial in reducing mortality related to CAD and HF in the population. Key words: Gensini score, coronary artery disease, left ventricular ejection fraction, optical coherence tomography angiography, vascular density