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Objective To investigate the safety and efficacy of a self-developed novel multi-electrode radiofrequency ablation catheter (Spark) for catheter-based renal denervation (RDN). Methods A total of 14 experimental miniature pigs were randomly divided into four groups (55°& 5-watt, 55°& 8-watt, 65°& 5-watt, and 65° & 8-watt groups). Spark was used for left and right renal artery radiofrequency ablation. Blood samples collected from renal arteries and veins as well as renal arteriography were performed on all animals before, immediately after, and three months after procedure to evaluate the effects of Spark on the levels of plasma renin, aldosterone, angiotensin I, and angiotensin II as well as the pathological changes of renal arteries. Results One pig died of an anesthetic accident, 13 pigs successfully underwent the bilateral renal artery ablation. Compared with basic measurements, pigs in all the four groups had significantly decreased mean arterial pressure after procedure. Histopathological analysis showed that this procedure could result in intimal hyperplasia, significant peripheral sympathetic nerve damage in the renal arteries such as inflammatory cell infiltration and fibrosis in perineurium, uneven distribution of nerve fibers, tissue necrosis, severe vacuolization, fragmented and unclear nucleoli myelin degeneration, sparse axons, and interruption of continuity. In addition, the renal artery radiofrequency ablation could significantly reduce the levels of plasma renin, aldosterone, angiotensin I, and angiotensin II in pigs. Conclusions The results suggest that this type of multi-electrode catheter-based radiofrequency ablation could effectively remove peripheral renal sympathetic nerves and reduce the activity of systemic renin-angiotensin system in pigs, thus facilitating the control of systemic blood pressure in pigs.

The SPIRIT checklist. (PDF 366Â kb)

SPIRIT figure. (PDF 311Â kb)

Objective To evaluate the utility of multi-slice computed tomography (MSCT) in assessing acute non-reperfused myocardial infarct size. Methods Seven domestic pigs (mean weight 17.3 ± 1.9 kg) underwent ligation of the distal left anterior descending artery to establish a model of acute myocardial infarction (MI). MSCT and triphenyltetrazolium chloride (TTC) staining were performed two hours later. The following data were acquired and analyzed: MI volume (%), CT values of the infarcted region, left ventricular cavity and normal cardiac tissue at various scanning time-points (1, 5, 10, 15, 20 min after contrast injection). Results Using MSCT, the overall MI volume showed a time-dependent decrease, with a reduction of 28.87% after 20 min. The greatest reduction occurred at the 5 min time-point. In TTC staining, MI volume was 9.87% ± 2.44%. When MI size, as determined by MSCT, was compared with that by TTC staining in Bland-Altman plots, there was a better agreement at 5, 10, and 15 min time-points at 1 and 20 min. Conclusions The study indicates that double-phase scanning examination using MSCT is a useful tool to assess MI size, and the optimal late-phase scanning time-point set within 5–15 min of contrast injection.

Ghrelin/GHS-R axis is known as its role in stimulating growth hormone release. Besides, it is also implicated in the regulation of atherosclerosis (AS), a chronic vascular disease that has been recognized as the main cause of coronary heart disease and cerebrovascular disease. It has been reported that both Ghrelin and AMPK play protective roles in AS by inhibiting the inflammatory response as well as cell proliferation. However, it remains unclear whether AMPK pathway is involved in Ghrelin/GHS-R-mediated inhibition of the inflammatory response and cell proliferation in AS. Here, we established the GHS-R gene knockout mice (GHS-R(-/-)) and found that AMPK activity is notably down-regulated in endothelial cells (ECs) of GHS-R(-/-) mice and the ECs from GHS-R(-/-) mice possess higher proliferative capability than the ECs from wild-type mice. Moreover, AMPK is activated in primary ECs upon Ghrelin induction in vitro. Taking together, the present study unravels that Ghrelin/GHS-R could efficiently activate AMPK in ECs, suggesting a possible mechanism that the roles of Ghrelin/GHS-R in the inhibition of inflammatory response and cell proliferation in AS disease may be partially mediated by activating AMPK.

Aim: The aim of the present study was to explore the role of receptor tyrosine kinases (RTKs) in the regulation of expression of PTX-3, a protector in atherosclerosis. Methods: Human monocytic U937 cells were infected with a shRNA lentiviral vector library targeting human RTKs upon LPS stimuli and PTX-3 expression was determined by ELISA analysis. The involvement of downstream signaling in the regulation of PTX-3 expression was analyzed by both Western blotting and ELISA assay. Results: We found that knocking down of ERBB2/3, EPHA7, FGFR3 and RET impaired PTX-3 expression without effects on cell growth or viability. Moreover, inhibition of AKT, the downstream effector of ERBB2/3, also reduced PTX-3 expression. Furthermore, we showed that FGFR3 inhibition by anti-cancer drugs attenuated p38 activity, in turn induced a reduction of PTX-3 expression. Conclusion: Altogether, our study demonstrates the role of RTKs in the regulation of PTX-3 expression and uncovers a potential cardiotoxicity effect of RTK inhibitor treatments in cancer patients who have symptoms of atherosclerosis or are at the risk of atherosclerosis.

BACKGROUND: Data on the relevance of the location of coronary bifurcation lesions treated by crush stenting with outcomes were limited. HYPOTHESIS: We hypothesized that the location of the bifurcation lesion correlated with clinical outcome. METHOD: A total of 212 patients with 230 true bifurcation lesions treated by crush stenting with drug‐eluting stents (DES) were assessed prospectively. Surveillance quantitative angiographies were indexed at 8 months after procedure. Primary endpoint was major adverse cardiac events (MACE), defined as cardiac death, myocardial infarction, and target lesion revascularization (TLR). RESULTS: Patients in the distal right coronary artery (RCAd) group were characterized by higher proportions of prior myocardial infarction and very tortuous lesions. However, lesions in the RCAd group, compared to those of other groups, had the lowest late lumen loss, with resultant lowest incidence of MACE at a mean follow‐up of 268±35 days. Independent predictors of MACE included unsatisfied kissing (KUS; hazard ratio [HR]: 12.14, 95% confidence interval [CI]: 4.01–12.10, P = .001) and non‐RCA lesion (HR: 20.69, 95% CI: 5.05–22.38, P = .001), while those of TLR were KUS (HR: 10.21, 95% CI: 0.01–0.34, P = .002), bifurcation angle (HR: 4.728, 95% CI: 2.541–4.109, P = .001), and non‐RCA lesion (HR: 16.05, 95%CI: 1.01–4.83, P = .001). CONCLUSIONS: Classical crush stenting with drug‐eluting stents is associated with significantly better outcomes in RCAd. Quality of kissing inflation is mandatory to improve outcome. Copyright © 2009 Wiley Periodicals, Inc.