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Background and objectives The hemodynamic evaluation of coronary stenoses undergoes a transition from wire-based invasive measurements to image-based computational assessments. However, fractional flow reserve (FFR) values derived from coronary CT angiography (CCTA) and angiography-based quantitative flow ratio have certain limitations in accuracy and efficiency, preventing their widespread use in routine practice. Hence, we aimed to investigate the diagnostic performance of FFR derived from the integration of CCTA and invasive angiography (FFRCT-angio) with artificial intelligence assistance in patients with stable coronary artery disease (CAD). Methods Forty stable CAD patients with 67 target vessels (50%–90% diameter stenosis) were included in this single-center retrospective study. All patients underwent CCTA followed by coronary angiography with FFR measurement within 30 days. Both CCTA and angiographic images were combined to generate a three-dimensional reconstruction of the coronary arteries using artificial intelligence. Subsequently, functional assessment was performed through a deep learning algorithm. FFR was used as the reference. Results FFRCT-angio values were significantly correlated with FFR values (r = 0.81, P < 0.001, Spearman analysis). Per-vessel diagnostic accuracy of FFRCT-angio was 92.54%. Sensitivity and specificity in identifying ischemic lesions were 100% and 88.10%, respectively. Positive predictive value and negative predictive value were 83.33% and 100%, respectively. Moreover, the diagnostic performance of FFRCT-angio was satisfactory in different target vessels and different segment lesions. Conclusions FFRCT-angio exhibits excellent diagnostic performance of identifying ischemic lesions in patients with stable CAD. Combining CCTA and angiographic imaging, FFRCT-angio may represent an effective and practical alternative to invasive FFR in selected patients.

Aims Aging is the most significant contributor to the increasing prevalence of atrial fibrillation (AF). The gut microbiota dysbiosis is involved in age-related diseases. However, whether the aged-associated dysbiosis contributes to age-related AF is still unknown. Direct demonstration that the aged gut microbiota is sufficient to transmit the enhanced AF susceptibility in a young host via microbiota-intestinal barrier-atria axis has not yet been reported. This study aimed to determine whether gut microbiota dysbiosis affects age-related AF. Methods and results Herein, by using a fecal microbiota transplantation (FMT) rat model, we demonstrated that the high AF susceptibility of aged rats could be transmitted to a young host. Specially, we found the dramatically increased levels of circulating lipopolysaccharide (LPS) and glucose led to the up-regulated expression of NLR family pyrin domain containing 3 (NLRP3)-inflammasome, promoting the development of AF which depended on the enhanced atrial fibrosis in recipient host. Inhibition of inflammasome by a potent and selective inhibitor of the NLRP3 inflammasome, MCC950, resulted in a lower atrial fibrosis and AF susceptibility. Then we conducted cross-sectional clinical studies to explore the effect of aging on the altering trends with glucose levels and circulating LPS among clinical individuals in two China hospitals. We found that both of serum LPS and glucose levels were progressively increased in elderly patients as compared with those young. Furthermore, the aging phenotype of circulating LPS and glucose levels, intestinal structure and atrial NLRP3-inflammasome of rats were also confirmed in clinical AF patients. Finally, aged rats colonized with youthful microbiota restored intestinal structure and atrial NLRP3-inflammasome activity, which suppressed the development of aged-related AF. Conclusions Collectively, these studies described a novel causal role of aberrant gut microbiota in the pathogenesis of age-related AF, which indicates that the microbiota-intestinal barrier-atrial NLRP3 inflammasome axis may be a rational molecular target for the treatment of aged-related arrhythmia disease. Translational perspective The current study demonstrates that aged-associated microbiota dysbiosis promotes AF in part through a microbiota-gut-atria axis. Increased AF susceptibility due to enhanced atrial NLRP3-inflammasome activity by LPS and high glucose was found in an aged FMT rat model, and also confirmed within elderly clinical individuals. In a long-term FMT rat study, the AF susceptibility was ameliorated by treatment with youthful microbiota. The present findings can further increase our understanding of aged-related AF and address a promising therapeutic strategy that involves modulation of gut microbiota composition.

Spexin (SPX) is a novel peptide with pleiotropic functions in adipose tissue including energy balance adjustment, fatty acid uptake, and glucose homeostasis. SPX level is closely associated with cardiovascular risk factors such as age, obesity, hypertension, and diabetes; however, its physiological significance in the cardiovascular system remains mostly undefined. We therefore here investigated the roles of SPX in regulating hypoxia-induced alterations in energy metabolism and mitochondrial function. We firstly confirmed that SPX is expressed in human and mouse cardiac tissue and documented that exposure to hypoxia in vitro reduces SPX level in rat H9C2 cardiomyocytes and primary neonatal rat ventricular myocytes (NRVMs). We then treated primary NRVMs with SPX before exposure to hypoxia, which (1) promoted fatty acid metabolism by enhancing expression of FAT/CD36, CPT1, ACADM, and PPAR-a and PGC1-a; (2) did not improve impaired glucose uptake; and (3) significantly prevented the downregulation of TFAM and mitochondrial electron transport chain complex and restrained UCP2 level and reactive oxygen species (ROS) production, thus enhancing ATP level in cardiomyocytes. In summary, SPX protects energy and mitochondrial homeostasis of cardiomyocytes during hypoxia, thereby highlighting the potential importance of SPX in the treatment of cardiovascular diseases.

Aging plays a critical role in the genesis of atrial fibrillation (AF) and also changes the gut microbes. Whether the aging-associated gut dysbiosis contributes to the development of aging-related AF and whether the gut microbes can be a target to prevent aging-related AF remains unknown.16S rRNA gene sequencing was performed to reveal the changes of gut microbes in elderly patients with AF, and the result showed that the intestinal abundance of B. fragilis was significantly decreased in elderly patients with AF. Subsequently, we examined the impact of B. fragilis supplementation on AF promotion, atrial structural remodeling and inflammation response in D-galactose induced aging rats. We found that oral administration of B. fragilis prevented AF inducibility and duration, which was associated with attenuation of atrial senescence, apoptosis and fibrosis. Furthermore, B. fragilis significantly diminished the systemic and atrial inflammation, which is accompanied by an increase in the number of Treg cells in the spleen and blood. More importantly, we found that the circulation level of polysaccharide A (PSA), the metabolite synthesized by B. fragilis, was reduced in elderly patients with AF and could predict the occurrence of AF, and B. fragilis increased the circulation concentration of PSA in D-galactose induced aging rats.The abundance of B. fragilis was lower in elderly patients with AF. Oral administration of B. fragilis significantly attenuated inflammatory response by increasing Treg cells, thereby preventing atrial structural remodeling and inhibiting AF promotion in D-galactose induced aging rats. This study provides experimental evidence for the effectiveness of targeting gut microbes in the prevention of aging-related AF.

Background: Aging is the most significant contributor to the increasing prevalence of atrial fibrillation (AF). The gut microbiota dysbiosis is involved in age-associated diseases. However, whether age-associated gut microbial dysbiosis contributes to AF is still unknown. The aim of this study was to evaluate the effect of gut microbiota on the susceptibility of aging-induced AF and to elucidate the underlying mechanisms. Results: The gut microbiota profiling of fecal samples in aged (22-24 months old) and young (2-3 months old) rats was performed by 16S ribosomal RNA gene analysis. A rat model of fecal microbiota transplantation (FMT) was established for analyzing the possible role of age-associated gut microbial dysbiosis in AF. Here, we found that aging process led to marked shift of the microbiota spectrum. The microbiota in young rats following FMT resembled that of aged microbiota and transmitted the increased AF susceptibility by elevation of circulating lipopolysaccharide (LPS). The mechanism for LPS-driven atrial pro-arrhythmic action was dependent on the activation of atrial nucleotide binding and oligomerization domain-like receptor family pyrin domain-containing (NLRP3)-inflammasome. Inhibition of inflammasome by MCC950 resulted in lower atrial fibrosis and AF susceptibility. In addition, atrial fibrosis, plasma LPS concentration, plasma glucose to oral glucose tolerance test (OGTT), intestinal permeability, and gut pathology were significantly increased in elderly human subjects. Finally, altering the microbiota in aged recipient to resemble that of young restored the intestinal barrier dysfunction and LPS and impaired glucose tolerance, and the worse outcomes of aged dysbiosis on atrial fibrosis and AF susceptibility were abrogated. Conclusions: These data suggest that age-associated microbial dysbiosis induces circulating LPS and impairs glucose tolerance, and thereby promotes AF susceptibility through enhanced activity of atrial NLRP3-inflammasome.

Inability to advance a balloon is a well-recognized cause leading to a failure in recanalization of chronic total occlusions (CTOs) despite successfully passing a guidewire. A few techniques and devices have been introduced to facilitate balloon passage, especially the use of Tornus catheter. However, complex manipulation, expensive cost, and availability limit the application of these methods. This study was to evaluate the efficiency and safety of "seesaw balloon-wire cutting" technique in comparison with Tornus catheter for balloon uncrossable CTOs.Eighty patients with balloon uncrossable CTOs were enrolled in this study. Among them, 40 patients treated with "seesaw balloon-wire cutting" technique were consecutively investigated and 40 patients treated with Tornus catheter before were matched retrospectively. A rotablator or retrograde strategy was taken as a bail-out strategy. Success rates of device and procedure and complication rate were assessed. Complications included coronary dissection, cardiac tamponade, death, Q-wave myocardial infarction (MI), non-Q-wave MI, emergency PCI and bypass surgery.Compared with the Tornus catheter, device success rate was significantly higher with the "seesaw balloon-wire cutting" technique (87.5% vs. 45.0%, P0.001), and the mean procedural time was much shorter (90.5±8.3min vs. 141.5±21.3min, P0.001). The procedural success rate was also higher with the "seesaw balloon-wire cutting" technique (92.5% vs.72.5%, P=0.037). There were no differences in complication rate.The "seesaw balloon-wire cutting" technique is superior to the Tornus catheter in treating balloon uncrossable CTOs.

Blood pressure variability (BPV) is a powerful predictor of end-organ damage, cardiovascular events and mortality independently of the BP level. Calcium channel blockers may offer an advantage over other first-line antihypertensive drugs by preventing increased BPV. But the effect of alpha-receptor blockers on BPV in hypertensive patients is still unclear.In this crossover trial, 36 hypertensive patients were randomly assigned to two groups, receiving doxazosin mesylate gastrointestinal therapeutic system (GITS) (4 mg/day) or nifedipine GITS (30 mg/day) for 12 weeks, followed by a 2-week washout period then a 12-week crossover phase. At baseline and after 12-week treatment, 24-hour ambulatory BP monitoring was performed. BPV was evaluated through standard deviation (SD), coefficient of variation (CV), and average real variability (ARV) of systolic BP (SBP) and diastolic BP (DBP) during daytime, nighttime and over 24 hours.After 12-week treatment, both doxazosin and nifedipine significantly decreased SBP and DBP (P0.05), whereas no between-group differences were shown (P0.05). Systolic BPV (24-hour SD, CV, and ARV; daytime SD; nighttime SD and CV) and diastolic BPV (24-hour SD and ARV) were significantly lowered by nifedipine (P0.05); doxazosin resulted in significant reductions of systolic BPV (24-hour SD, CV and ARV; daytime SD; nighttime SD) and diastolic BPV (nighttime SD and CV) (P0.05). Doxazosin was revealed to be as effective as nifedipine for reducing BPV (P0.05) except for 24-hour SBP ARV.Doxazosin mesylate GITS had similar therapeutic effects on BP, BP SD, and BP CV lowering as nifedipine GITS in patients with mild-to-moderate essential hypertension.

Background Whether chronic obstructive sleep apnea ( OSA ) could promote epicardial adipose tissue ( EAT ) secretion of profibrotic adipokines, and thereby contribute to atrial fibrosis, and the potential therapeutic effects of metoprolol remain unknown. Methods and Results A chronic OSA canine model was established by repeatedly clamping the endotracheal tube for and then reopening it for 4 hours every other day for 12 weeks. In a metoprolol treatment group, metoprolol succinate was administered daily for 12 weeks. The EAT infiltration and left atrial fibrosis were examined. The expressions of adipokines secreted by EAT and hypoxic 3T3‐L1 adipocytes were detected. The changes in collagen synthesis, transforming growth factor‐β1 expression, and cell differentiation and proliferation in cardiac fibroblasts induced by hypoxic 3T3‐L1 adipocyte‐derived conditioned medium were further analyzed. Chronic OSA induced infiltration of EAT into the left atrium. OSA enhanced the profibrotic effect of EAT on the adjacent atrial myocardium. Moreover, OSA induced profibrotic cytokine secretion from EAT . We also found that hypoxia induced adipokine secretion in cultured adipocytes, and the medium conditioned by the hypoxic adipocytes increased collagen and transforming growth factor‐β1 protein expression and cell proliferation of cardiac fibroblasts. More importantly, metoprolol attenuated infiltration of EAT and alleviated the profibrotic effect of EAT by inhibiting adipokine secretion. Metoprolol also inhibited hypoxia‐induced adipokine secretion in adipocytes and thereby blocked the hypoxic adipocyte–derived conditioned medium–induced fibrotic response of cardiac fibroblasts. Conclusions Chronic OSA enhanced the profibrotic effect of EAT on the neighboring atrial myocardium by stimulating the secretion of profibrotic adipokines from EAT , which was significantly attenuated by metoprolol. This study gives insights into mechanisms underlying OSA ‐induced atrial fibrillation and also provides experimental evidence for the protective effects of metoprolol.

As an effective means of traffic organization, one-way traffic plays an important role in easing traffic congestion. However, the reality is often a one-way traffic organization based on experience, and new traffic problems have emerged during the implementation process. Based on the discussion of one-way traffic setting conditions, this paper models and evaluates the one-way traffic organization scheme that meets the conditions. The fuzzy distribution-analytic hierarchy process is used to evaluate the traffic patency, safety, economy, comfort and environmental impact of the organization scheme. Then, the setting condition-evaluation method is applied to the actual case in combination with VISSIM simulation for inspection. Finally, the experimental results show that the setting conditions-evaluation method can provide a scientific basis for the design and comparison process of one-way traffic organization.

Autophagy, a bidirectional degradative process extensively occurring in eukaryotes, has been revealed as a potential therapeutic target for several cardiovascular diseases. However, its role in atrial fibrillation (AF) remains largely unknown. This study aimed to determine the role of autophagy in atrial electrical remodeling under AF condition. Here, we reported that autophagic flux was markedly activated in atria of persistent AF patients and rabbit model of atrial rapid pacing (RAP). We also observed that the key autophagy-related gene7 (ATG7) significantly upregulated in AF patients as well as tachypacing rabbits. Moreover, lentivirus-mediated ATG7 knockdown and overexpression in rabbits were employed to clarify the effects of autophagy on atrial electrophysiology via intracardiac operation and patch-clamp experiments. Lentivirus-mediated ATG7 knockdown or autophagy inhibitor chloroquine (CQ) restored the shortened atrial effective refractory period (AERP) and alleviated the AF vulnerability caused by tachypacing in rabbits. Conversely, ATG7 overexpression significantly promoted the incidence and persistence of AF and decreased L-type calcium channel (Cav1.2 α-subunits), along with abbreviated action potential duration (APD) and diminished L-type calcium current (ICa,L). Furthermore, the co-localization and interaction of Cav1.2 with LC3B-positive autophagosomes enhanced when autophagy was activated in atrial myocytes. Tachypacing-induced autophagic degradation of Cav1.2 required ubiquitin signal through the recruitment of ubiquitin-binding proteins RFP2 and p62, which guided Cav1.2 to autophagosomes. These findings suggest that autophagy induces atrial electrical remodeling via ubiquitin-dependent selective degradation of Cav1.2 and provide a novel and promising strategy for preventing AF development.

Coronary artery perforation (CAP) is an infrequent yet potentially life-threatening complication of percutaneous coronary intervention. We report, for the first time, two cases of successful closure of guidewire-induced distal CAP with silk suture embolization using a microcatheter. This technique appears to be safe, simple, and effective for the treatment of distal guidewire perforations, even in refractory cases.

Background The prevalence of atrial fibrillation ( AF ) is significantly higher in rheumatoid arthritis ( RA ) patients, but the underlying mechanisms remain poorly understood. The goal of this study was to assess the effects of RA on AF susceptibility and atrial arrhythmogenic remodeling in a rat model of RA . Methods and Results Collagen‐induced arthritis was induced in rats by immunization with type II collagen in Freund's incomplete adjuvant. Among the rats that developed arthritis, AF susceptibility and atrial remodeling were examined 8 weeks after the primary immunization. AF inducibility and duration were substantially increased in collagen‐induced arthritis rats, and AF duration was significantly and positively correlated with the serum IL ‐6 and TNF ‐α levels. Rats with collagen‐induced arthritis showed prolonged atrial conduction time with no changes in the atrial effective refractory period. Atrial conduction delay was accompanied by significantly increased atrial fibrosis. In addition, atrial structural and autonomic remodeling, including left atrial dilation, apoptosis and autophagy of atrial myocytes, and atrial heterogeneous sympathetic hyperinnervation, was observed. Interestingly, we found that collagen‐induced arthritis had no significant effects on connexins, Nav1.5, and the main ion channels' protein expressions in atria. Conclusions We demonstrated that RA increased AF susceptibility by inducing AF ‐promoting atrial remodeling. This study may provide insights into mechanisms underlying RA ‐induced AF and validate a model that is suitable for further mechanistic and therapeutic exploration.

Acute lung injury (ALI), acute respiratory distress syndrome (ARDS), is actually involved in an ongoing and uncontrolled inflammatory response in lung tissues. Although extensive studies suggested that phospodiesterase type 4B (PDE4B) may be related to inflammation, the underlying cell biological mechanism of ALI remains unclear. To further investigate the mechanism how PDE4B take part in inflammatory response and the maintenance of vascular integrity, we established the experimental model of ALI in vitro and in vivo. In vitro, we found that Cilomilast, Diazepam and PDE4B knockout could potently inhibit the LPS-induced NF-κB activation and inflammatory response in multiple cell types, including lung epithelial cells (A549), pulmonary microvascular endothelial cells (PMVECs) and vascular smooth muscle cells (VSMCs). Besides, PDE4B deletion attenuated the LPS-induced ROS generation. In vivo, PDE4B deletion could attenuate the lung water content, histological signs of pulmonary injury and elevate the ratio of partial pressure of arterial O2 to fraction of inspired O2 (PaO2/FIO2 ratio). Additionally, PDE4B deletion reduced LPS-induced vascular permeability. Collectively, our results strongly indicates that PDE4B is a valid target for anti-ALI.

Background: Previous studies revealed that culprit vessels of ST-segment elevation myocardial infarction (STEMI) were often related to mild or moderate stenosis. However, recent studies suggested that severe stenosis was primarily found in culprit lesions. The objective of this study was to analyze the stenosis severity of culprit lesions in STEMI patients and to clarify the paradoxical results. Methods: A total of 489 consecutive STEMI patients who underwent primary percutaneous coronary intervention were retrospectively studied from January 2012 to December 2014. The patients were divided into three groups based on stenosis severity using quantitative coronary analysis: Group A, 314 cases, stenosis ≥70%; Group B, 127 cases, stenosis 50–70%; and Group C, 48 cases, stenosis ≤50%. The clinical, demographic, and angiographic data of all groups were analyzed. Results: Patients in Group A exhibited a significantly higher prevalence of history of angina pectoris (95.9% vs. 62.5%, P < 0.001), multivessel disease (73.2% vs. 54.2%, P = 0.007), and lower cardiac ejection fraction (53.3 ± 8.6 vs. 56.8 ± 8.4, P = 0.009) than those in Group C. Multivariable analysis revealed that history of angina pectoris (odds ratio [OR]: 13.89, 95% confidence interval [CI]: 6.21–31.11) and multivessel disease (OR: 2.32, 95% CI: 1.25–4.31) were correlated with severe stenosis of the culprit lesion in Group A. Conclusions: Most culprit lesions in STEMI patients were severe stenosis. These patients exhibited a higher prevalence of angina history and multivessel diseases.

Aims. Oxidative stress has recently been implicated in atrial fibrillation (AF); however, the mechanisms remain unclear. Herein, we hypothesize that probucol can attenuate atrial structure remodeling. Methods. Twenty dogs were randomly divided into sham-operated, control, and probucol-treated groups. We identified apoptosis and histopathological changes in the atria. Oxidative stress was measured by lipid peroxidation and echocardiographic examinations were performed. Results. Atrial apoptosis indexes were dramatically decreased in the probucol-treated group compared to the control group. Relative to the control group, the percentage of myolysis was dramatically decreased in the probucol-treated group (p < 0.01). There was less lipid peroxidation in the probucol-treated group than the control group. Atrial function was dramatically elevated in the probucol-treated group. Conclusions. The results of this study indicate that the antioxidant probucol suppresses atrial structural remodeling and may act as a new therapy for AF.

Excessive movement of coronary stents within the artery can make accurate stent placement difficult. This study assessed the use of the floating-wire technique to reduce stent motion to improve placement accuracy.During percutaneous coronary intervention, if excessive stent movement prevented accurate stent placement, the floating-wire technique was performed to reduce stent motion within the coronary artery during both stent positioning and deployment. Postprocedural angiograms were analyzed by two independent operators to measure the motion length of the stent delivery system relative to the coronary artery before and after using the floating-wire technique. The floating-wire technique was considered necessary in 19 patients. No procedural complications occurred. The extent of motion was markedly reduced by using the floating-wire technique (4.04 ± 1.25 mm to 1.11 ± 0.81 mm; P.001).The floating-wire technique is an effective and safe method to reduce stent movement and facilitate accurate stent deployment. This simple technique can be easily applied in any interventional cardiac catheterization laboratory without the need for additional training or equipment.

Background/Aims: Angiotensin II receptor blockers (ARBs) have been proved to be effective in preventing atrial structural and electrical remodelinq in atrial fibrillation (AF). Previous studies have shown that parasympathetic remodeling plays an important role in AF. However, the effects of ARBs on atrial parasympathetic remodeling in AF and the underlying mechanisms are still unknown. Methods: Canines were divided into sham-operated, pacing and valsartan + pacing groups. Rats and HL-1 cardiomyocytes were divided into control, angiotensin II (Ang II) and Ang II + valsartan groups, respectively. Atrial parasympathetic remodeling was quantified by immunocytochemical staining with anti-choline acetyltransferase (ChAT) antibody. Western blot was used to analysis the protein expression of neurturin. Results: Both inducibility and duration were increased in chronic atrial rapid-pacing canine model, which was significantly inhibited by the treatment with valsartan. The density of ChAT-positive nerves and the protein level of neurturin in the atria of pacing canines were both increased than those in sham-operated canines. Ang II treatment not only induced atrial parasympathetic remodeling in rats, but also up-regulated the protein expression of neurturin. Valsartan significantly prevented atrial parasympathetic remodeling, and suppressed the protein expression of neurturin. Meanwhile, valsartan inhibited Ang II -induced up-regulation of neurturin and MAPKs in cultured cardiac myocytes. Inhibition of MAPKs dramatically attenuated neurturin up-regulation induced by Ang II. Conclusion: Parasympathetic remodeling was present in animals subjected to rapid pacing or Ang II infusion, which was mediated by MAPKs/neurturin pathway. Valsartan is able to prevent atrial parasympathetic remodeling and the occurrence of AF via inhibiting MAPKs/neurturin pathway.

Obstructive sleep apnea (OSA) is closely related to atrial fibrillation (AF). However, the roles and mechanisms of chronic OSA in atrial remodeling are still unclear. Canine model of chronic OSA was simulated by stopping the ventilator and closing the airway for 4 h per day and lasting for 12 weeks. AF inducibility and duration was increased while atrial effective refractory period (AERP) was shortened after chronic apnea. Meanwhile, upregulation of proteins encoding inward rectifier K(+) current (IK1), delayed rectifier K(+) current (IKr and IKs), acetylcholine activated K(+) current (IKACh), transient outward K(+) current (Ito) and ultra-rapid delayed rectifier potassium current (IKur) as well as downregulation of protein encoding L-type Ca(2+) current (ICa,L) were found after chronic OSA. Besides abnormal electrical activity, chronic OSA induced apoptosis and interstitial fibrosis of atrial myocytes, which was partly mediated by caspase 9, phosphorylation of extracellular-regulated kinase 1/2, and α-smooth muscle actin. In addition, atrial sympathetic and parasympathetic hyperinnervation were found manifesting by enhanced growth-associated protein 43, tyrosine hydroxylase and elevated choline acetyltransferase. Moreover, protein expression of β1, β2, and M2 receptor were markedly increased by chronic OSA. In summary, we firstly demonstrated in canine model that chronic OSA could shorten AERP and lead to altered expression of important channel proteins, moreover, induce atrial structure remodeling by increased atrial apoptosis, fibrosis, and autonomic remodeling, eventually promoting the development of a substrate of AF. Our findings suggested that reversing atrial remodeling might be a potential therapeutic strategy for OSA-induced AF.

Balloon crossing failure after passing a guidewire usually leads to unsuccessful percutaneous recanalization of chronic total occlusions (CTOs). We sought to investigate a novel technique for solving this problem.Twenty-one patients with failed balloon crossing through CTOs after successful guidewire passing were treated with the "seesaw balloon-wire cutting" technique between July 2012 and May 2013. The main process of this technique was to insert two guidewires (guidewire A and guidewire B) into the distal true lumen of CTOs and then to advance two short and lowprofile balloons (balloon A and balloon B) over the two guidewires, respectively. Balloon A was first advanced over guidewire A as distally as possible, and then was inflated with high pressure (≥18 atm) to press guidewire B, producing a cutting power to crush the proximal fibrous cap of the CTO. Subsequently, balloon A was withdrawn slightly, and balloon B was advanced as distally as possible and then was inflated to press guidewire A, producing a similar cutting effect to crush the proximal fibrous cap on the other side. The two balloons were progressed alternatively until one of them was able to cross through the occluded segment.This new technique was successfully applied in 17 patients (81.0%), leading to procedural success of their CTOs. The technique failed in 4 patients (19.0%) due to heavy calcification. No complications occurred in all patients.The seesaw balloon-wire cutting technique is an effective and safe approach to facilitate balloon crossing during CTO interventions.

Objective To investigate whether microRNAs (miRs) can serve as novel biomarkers for in-stent restenosis (ISR). Methods This retrospective, observational single-centre study was conducted at the cardiovascular department of a tertiary hospital centre in the north of China. Follow-up coronary angiography at 6 to 12 months was performed in 181 consecutive patients implanted with drug-eluting stents. Fifty-two healthy volunteers served as the control group. The plasma miRs levels were analyzed by quantitative real-time PCR. Receiver-operating characteristic curve (ROC) analysis was performed to investigate the characters of these miRs as potential biomarkers of ISR. Results MiR-21 levels in ISR patients were significantly higher than those in non-ISR patients and healthy controls (P

This study was designed to evaluate the effects of a calpain inhibitor on cardiac muscle apoptosis in rapid pacing canine atrial fibrillation (AF) models.Twenty one dogs were divided into three groups: a sham operation group, a control AF group and a calpain inhibitor group. Sustained AF was induced by rapid right atrium pacing at 600 beats per minute. N-Acetyl-Leu-Leu-Met (1.0 mg/kg/day) was administered in the calpain inhibitor group for three weeks. The activity of calpain I and cardiomyocyte apoptosis were measured by fluorometry and TUNEL assay, respectively. Protein expression of caspase-3 was detected by Western blot. The localizations of caspase-3, caspase-8, bcl-2 and ARC were assessed by immunohistochemistry.In comparison to the sham operation group, the activity of calpain I was significantly increased in the control AF group (2.3 fold, p0.001), and decreased in the calpain inhibitor group (1.1 fold, p0.005). The calpain activity correlated with the apoptosis index (r = 0.9, p0.05). The apoptosis index was 1.0 +/- 0.2%, 11.8 +/- 6.8% and 3.5 +/- 2.1% in the sham operation group, control AF group and calpain inhibitor group, respectively. In the sham operation group, control AF group and calpain inhibitor group, the expressions of caspase-3 (13.0 +/- 1.9%, 52.8 +/- 4.3% and 33.6 +/- 3.7%), caspase-8 (40.1 +/- 5.3%, 92.6 +/- 6.5% and 55.3 +/- 5.9%), bcl-2 (65.8 +/- 6.1%, 52.0 +/- 5.7% and 69.9 +/- 5.3%) and ARC (70.2 +/- 8.6%, 68.8 +/- 7.3% and 81.5 +/- 8.8%) were calculated as immunohistochemical indexes, respectively.The calpain inhibitor N-Acetyl-Leu-Leu-Met attenuated apoptosis through a complicated network of apoptosis-related proteins, which may result in improvement of structural remodeling in atrial fibrillation.

It has been demonstrated that stent implantation in a myocardial bridge is associated with a high restenosis rate; however, coronary perforation caused by stent implantation has been reported. The present report describes two myocardial bridge cases with severe coronary rupture soon after stent implantation. Previous studies have reported that the diameter of the bridge vessels was less than that of the proximal and distal vessels; thus, coronary perforation may be due to stent oversizing. To determine the risks and benefits associated with this therapeutic option, interventional therapy should be critically evaluated, and careful selection of balloon and drug-eluting stent size using intravascular ultrasound is recommended.

BACKGROUND Atrial fibrillation (AF) is accompanied by atrial structural remodeling. Calpain activity is induced during AF. To test a causal relationship between calpain activation and atrial structural changes, N-acetyl-Leu-Leu-Met (ALLM), a calpain inhibitor, was utilized in a canine AF model. METHODS Fifteen dogs were randomly divided into 3 groups: sham-operated group, control group and calpain inhibitor group; each with 5 dogs. Sustained AF was induced by rapid right atrium pacing at 600 beats per minute for 3 weeks. ALLM was administered at a dosage of 1.0 mg x kg(-1) x d(-1) in the calpain inhibitor group. Three weeks later, the proteolysis, protein expression of TnT and myosin, calpain I localization and expression and structural changes were examined in left atrial free walls, right atrial free walls and the interatrial septum respectively. Atrial size and contractile function were also measured by echocardiography. RESULTS Long-term rapid atrial pacing induced marked structural changes such as enlarged atrial volume, myolysis, degradation of TnT and myosin, accumulation of glycogen and changes in mitochondrial shape and size, which were paralleled by an increase in calpain activity. The positive correlation between calpain activity and the degree of myolysis (r(s) = 0.90 961, P < 0.0001) was demonstrated. In addition to structural abnormalities, pacing-induced atrial contractile dysfunction was observed in this study. The pacing-induced atrial structural alterations and loss of contractility were partially prevented by the calpain inhibitor ALLM. CONCLUSIONS Activation of calpain represents key features in the progression towards overt structural remodeling. Calpain inhibitor, ALLM, suppressed the increased calpain activity and reversed structural remodeling caused by sustained atrial fibrillation in the present model. Calpain inhibition may therefore provide a possibility for therapeutic intervention in AF.

Objectives Chronic excessive consumption of alcohol causes cardiac remodelling and eventually leads to alcoholic cardiomyopahty (ACM). A disintegrin and metalloproteinase-12 (ADAM-12) is involved in degradation of extracellular matrix using syndecan-4 as a primary cell surface receptor. This study aimed to investigate the role of ADAM-12/syndecan-4 signalling pathway in ventricular remodelling of ACM. Methods Fifty healthy Wistar rats were randomly divided into a control group (n=20) and an ACM group (n=30). Animals in the ACM group were given 10% alcohol ad libitum as the drinking water and 60% alcohol (5 ml kg −1 once per day) by intragastric administration in the first week; 10% alcohol ad libitum as the drinking water and 60% alcohol (10 ml kg −1 twice per day) by intragastric administration in the second week; 20% alcohol ad libitum as the drinking water and 60% alcohol (15 ml kg −1 twice per day) by intragastric administration from week 3 to week 16; and 30% alcohol ad libitum as the drinking water and 60% alcohol (15 ml kg −1 twice per day) by intragastric administration from week 17 to month 6. Animals in the control group received purified drinking water in the same regimen with alcohol treatment. Before and 6 months after initiating the study, left ventricular end diastolic diameter (LVEDD), left ventricular ejection fraction (LVEF), and fractional shortening (FS) were assessed by echocardiography. Histopathology and ultrastructure of myocardium were examined with light and electron microscopy; mRNA expressions of ADAM-12 and syndecan-4 were evaluated by real-time PCR; and protein expressions of ADAM-12 and syndecan-4 were analysed using immunohistochemistry and western blot, respectively. The expression of TIMP-3, an endogenous inhibitor of ADAM-12, was also tested. Results Following 6 months of alcohol feeding, LVEF and FS were reduced p Conclusions Along with decreased expression of TIMP-3, ADAM-12 and syndecan-4 are over-expressed and are associated with ventricular remodelling in ACM. Therefore, the ADAM-12/syndecan-4 signalling pathway may represent a new therapeutic target in the prevention and treatment of ventricular remodelling in ACM.