‘Coronary Sinus Filling Time’- For Diagnosis of Microvascular Disease in Patients with Chronic Stable Angina

Patients having angina with normal epicardial coronary arteries are often considered to have coronary microvascular dysfunction that may result in coronary slow flow. Delayed Coronary Sinus Filling Time (CSFT) may represent transit time through coronary microcirculation.We evaluated CSFT in patients having angina with normal epicardial coronary arteries and compared it with control population. Methods: 31 patients having definite angina or probable angina with positive exercise tolerance test with normal epicardial coronary arteries in coronary angiogram (CAG) were included in the study group. 31 patients having normal epicardial coronary arteries in CAG during preoperative evaluation before surgical treatment for valvular and congenital heart diseases were in control group. CSFT, TIMI (Thrombolysis In Myocardial Infarction) frame count, cTIMI (Corrected TIMI) frame count and TMP (TIMI Myocardial Perfusion) score were assessed in CAG of both group and compared between groups. Results: Patients’ Mean±SD of age in study and control group were 48.84±9.50years and 46.71±5.53years respectively with no significant difference (p=0.569) and there was female preponderance (55% and 65%) in both groups. CSFT was significantly prolonged in study group (4.22±0.71sec vs. 3.65±0.25sec, P value 0.001) but TIMI frame count, cTIMI and TMP showed no significant difference between two groups (25.71±5.74 vs. 26.74±3.81, p= 0.552; 14.76±3.6 vs. 15.4±2.56, p=0.449; 2.54±0.5 vs. 2.61±0.49, p=0.326; respectively). Conclusion: We concluded that CSFT was significantly prolonged in patients having angina with normal epicardial coronary arteries which might be a marker for diagnosis of coronary microvascular disease.