The effect of ticagrelor on myocardial microcirculation, cardiac function, and adverse cardiovascular events in STEMI patients after PCI.

OBJECTIVE: This study aimed to investigate the effects of ticagrelor on myocardial microcirculation, cardiac function, and adverse cardiovascular events in ST-segment elevation myocardial infarction (STEMI) patients after percutaneous coronary intervention (PCI). PATIENTS AND METHODS: A total of 80 STEMI patients admitted to our hospital from February 2020 to March 2023 were selected and included in the retrospective study, all receiving PCI treatment. They were randomly and retrospectively divided into a control group (40 cases) and an observation group (40 cases), and treated with clopidogrel and ticagrelor, respectively. The clinical effects were compared. RESULTS: The starting perfusion time of the contrast agent in the myocardial infarction area in the observation group was 2.22±0.27 s, and the peak perfusion time was 2.62±0.27 s, which was lower than those in the control group (2.51±0.29 s and 3.21±0.39 s, t=4.629, 7.867, p=0.000). The ratio of peak perfusion intensity between the two groups was significantly different (t=2.363, p=0.021). Left ventricular ejection fraction, stroke volume index, and cardiac index in the observation group were higher than those in the control group (55.03±6.03 vs. 52.33±5.13; 57.39±6.81 vs. 51.11±6.31 L/min·m-2; 3.49±0.45 vs. 3.12±0.38 mL/m2, t=2.157, 4.278, 3.973, p<0.05). The observation group had lower levels of brain natriuretic peptide and C-reactive protein compared to the control group (425.35±55.71 vs. 589.36±70.24 pg/mL; 15.13±1.03 vs. 21.64±2.74 mg/L; t=11.570, 14.066, p=0.000). There was no statistical significance in the incidence of adverse cardiovascular events between the two groups (2.50% vs. 7.50%, χ2=1.920, p=0.166). CONCLUSIONS: The use of ticagrelor can regulate myocardial microcirculation and improve cardiac function in STEMI patients undergoing PCI.

Blood flow index as an indicator of successful sciatic nerve block: a prospective observational study using laser speckle contrast imaging.

BACKGROUND: Laser speckle contrast imaging allows real-time, non-invasive, quantitative measurements of regional blood flow. The objectives of this prospective observational study were to use laser speckle contrast imaging to evaluate blood flow changes after sciatic nerve block, and to determine whether this novel optical technique can evaluate block success. METHODS: This observational study included 63 adult patients undergoing elective lower limb surgery with sciatic nerve block. Blood flow images and blood flow index (BFI) values of toes were recorded using laser speckle contrast imaging 5 min before nerve block and at 5 min intervals until 30 min after sciatic block. The sensitivity, specificity, and cut-off value of laser speckle contrast imaging for predicting successful sciatic block were determined by receiver operator characteristic (ROC) curve analysis. RESULTS: The BFI values of toes were significantly increased at each time point after successful sciatic block, compared with the baseline value obtained 5 min before nerve block; in failed sciatic block, there were no significant differences. For successful sciatic block, the highest increase of BFI value was at the big toe. BFI increase of the big toe at 10 min after sciatic block has great potential as an indicator of block success. The area under the ROC curve was 0.954 at a cut-off value of 8.48 perfusion units (PU) with a sensitivity of 89% and a specificity of 100%. CONCLUSIONS: Laser speckle contrast imaging might be an early, objective, quantitative, and reliable indicator of successful sciatic block. BFI increase of the big toe not reaching 8.48 PU within 10 min after sciatic block indicates block failure. CLINICAL TRIAL REGISTRATION: NCT03169517.