Application of hypoglossal microcirculation imaging system in observation of distal microcirculation after myocardial infarction

Objective To explore the feasibility of detecting cardiac microvessel with hypoglossal microcirculatory imaging system (abbreviated as microvision system), and explore its clinical value in diagnosis, treatment and prognosis evaluation of coronary microcirculation disorder. Methods Normal SD rats were used as research objects to detect the microcirculation of the main coronary artery and its branches with microvision system. Forty SD rats were randomly divided into two groups (20 each): myocardial infarction (MI) group and sham operation (Sham) group. The left anterior descending branch of coronary artery was ligated to make the model of myocardial infarction in MI group, and the sham group received the same treatment as in MI group but no ligation. The microvessel of left anterior descending branch was detected and analyzed in sham group and MI group before operation and 5, 10 and 20 minutes after operation by microvision system. The measured parameters included the total vessel density (TVD), the perfused vessel density (PVD), the proportion of perfused vessels (PPV), the microcirculatory flow index (MFI) and the heterogeneity index (HI). Results In microvision system, the left and right coronary vessels and their branches in the normal rat heart were clearly visible, the blood flow perfusion was continuous, and the blood vessels were dense and evenly distributed. In MI group, the longer the ligation time, the more blurred the vein of the microvessel. Furthermore, the blood flow was interrupted and the vessels were non-uniform distribution. The microcirculation was invisible and blood flow disappeared at 20min time point after infarction. Compared with that at 5min time point, TVD, PVD, PPV and MFI decreased, while HI increased at 10min and 20min time points (P