Efficacy of combined ultrasound and microbubble treatment for thrombolysis for rescuing ischemic tissues in rats at different time after thrombosis / 南方医科大学学报

<p><b>OBJECTIVE</b>To explore the relationship between the time after thrombosis and the efficacy of combined ultrasound and microbubble treatment for rescuing the ischemic tissues.</p><p><b>METHODS</b>Rat models of thrombosis in the right common iliac artery were established and received combined ultrasound and microbubble treatment at 3, 6 and 12 h after thrombosis. The recanalization rate of the right common iliac artery was assessed using both 2-dimensional and Doppler ultrasound. The plateau acoustic intensity (AI) was quantified for estimating the skeletal microvascular blood volume, and skeletal muscle injury markers including myoglobin (Mb) and creatinine kinase (CK) were measured using ELISA. Postmortem TUNEL staining was used to detect the apoptotic rate of skeletal muscle cells in the hind limb of the rats.</p><p><b>RESULTS</b>Compared with those in 3 h group, the recanalization rate and AI were significantly lower, and the levels of Mb and CK and the apoptotic rate of the skeletal muscle cells were significantly higher in both 6 h group and 12 h group ( < 0.05). Compared with those in 6 h group, the rats receiving treatment at 12 h after thrombosis showed significantly lowered AI and increased Mb, CK and apoptotic rate of the skeletal muscle cells ( < 0.05).</p><p><b>CONCLUSIONS</b>The efficacy of combined ultrasound and microbubble treatment for rescuing ischemic tissues tends to be attenuated as the time after thrombosis prolongs in rats.</p>

Mechanism of lumen loss of the left circumflex ostium after main vessel stent implantation: observations by intravascular ultrasound / 南方医科大学学报

<p><b>OBJECTIVE</b>To explore the mechanism of lumen loss of the left circumflex ostium after main vessel stent implantation.</p><p><b>METHODS</b>Twenty-eight patients undergoing provisional T technique were enrolled in this study. Intravascular ultrasound (IVUS) examination was performed before and after main vessel stenting and kissing balloon post-dilatation to evaluate the geometrical changes of the vessels.</p><p><b>RESULTS</b>The CSA of LCX ostium lumen decreased significantly from 5.9∓2 mm(2) to 4.9∓1.9 mm(2) (P<0.01) after the procedure, and the CSA of LCX ostium P and M increased from 5.4∓2.9 mmmm(2) to 5.7∓2.9 mm(2) (P=0.21) after the main vessel stenting. The changes in LCX ostium lumen CSA was correlated with the changes of LCX ostium EEM CSA but not the LCX ostium P and M CSA. After kissing balloon post-dilatation, the CSA of LCX ostium lumen increased from 4.9∓1.9 mm(2) to 5.5∓1.9 mm(2) (P<0.01) , and the CSA of LCX ostium P and M showed no obvious changes (5.7∓2.9 mmmm(2) vs 5.7∓2.6 mmmm(2), P=0.89). The changes of LCX ostium lumen CSA were correlated with the those of the LCX ostium EEM CSA (R=0.432, P=0.02).</p><p><b>CONCLUSION</b>After stent implantation from the LMCA to the LAD, most of lumen losses of the LCX are due to carina shift, and in occasional cases, plaque shift occurs from the distal LMCA to the ostium of the LCX. Kissing balloon technique can adjust carina shift but can not improve plaque shift.</p>

Atorvastatin prevents contrast agent-induced renal injury in patients undergoing coronary angiography by inhibiting oxidative stress / 南方医科大学学报

<p><b>OBJECTIVE</b>To evaluate the efficacy of atorvastatin in preventing contrast agent-induced nephropathy (CIN) in patients undergoing coronary angiography and explore the mechanism.</p><p><b>METHODS</b>A total of 180 patients undergoing coronary angiography or percutaneous coronary interventions (PCI) were randomized into regular dose and high dose atorvastatin groups (n=90). Serum creatinine (Scr), glomerular filtration rate (GFR), cystatin, peripheral blood levels of myeloperoxidase (MPO), malondialdehyde (MDA), and superoxide dismutase (SOD) before and after the procedure were compared between the two groups.</p><p><b>RESULTS</b>The incidence of CIN was significantly lower in high-dose atorvastatin group than in the regular dose group. At 48-72 h after the surgery, serum Scr and cystatin levels were significantly lower and eGFR was significantly higher in the high-dose group. At 24 h after the surgery, MPO and MDA levels were significantly lower, and SOD activity was significantly higher in high-dose group than in the regular dose group.</p><p><b>CONCLUSION</b>High-dose atorvastatin used before angiography is more effective than the regular dose in attenuating contrast agent-induced renal dysfunction, and its mechanism is related with the inhibition of oxidative stress.</p>