Retinal fluorescein angiography: A sensitive and specific tool to predict coronary slow flow

BACKGROUND: Obstructive coronary artery disease (OCAD) and coronary slow flow (CSF) are frequent angiographic findings for patients that have chest pain and require frequent hospital admission. The retina provides a window for detecting changes in microvasculature relating to the development of cardiovascular diseases such as arterial hypertension or coronary heart disease. OBJECTIVES: To assess the coronary and ocular circulations in patients with CSF and those with obstructive coronary artery disease. METHODS: A prospective study was conducted over 3.5 years, included a total of 105 subjects classified to 4 groups: Group I (OCAD): Included 30 patients with obstructive coronary artery disease, group II (CSF): Included 30 patients with coronary slow-flow, group III (Control 1): Included 30 healthy control persons and group IV (Control 2): Included 15 patients indicated for coronary angiography that proved normal. All participants were subjected to coronary angiography (except control group 1), ophthalmic artery Doppler for measuring Pulsatility index (PI) and resistivity index (RI) and Fluorescence angiography of retinal vessels. RESULTS: Patients with CSF showed slow flow retinal circulation (microcirculation) evidenced by prolonged fluorescein angiography (Arm-retina time [ART] & Arterio-venous Transit time [AVTT]). Ophthalmic artery Doppler measurements (RI & PI) were significantly delayed in OCAD and CSF patients. There was significant positive correlation between TIMI frame count in all subjects and ART, AVTT, PI, RI and Body Mass Index. Using ART cutoff value of >16 s predicted CSF with sensitivity and specificity of 100%, meanwhile AVTT of >2 s predicted CSF with a sensitivity 96.7% and specificity of 93.3. CONCLUSION: Both delayed arm-retina time and retinal arterio-venous transit times can accurately predict coronary slow-flow.