Application of a circular-shaped pulsed field ablation catheter with magnetic sensors for pulmonary vein isolation: a multi-centre clinical study report.

AIMS: A few studies have reported the effect and safety of pulsed field ablation (PFA) catheters for ablating atrial fibrillation (AF), which were mainly based on basket-shaped or flower-shaped designs. However, the clinical application of a circular-shaped multi-electrode catheter with magnetic sensors is very limited. To study the efficacy and safety of a PFA system in patients with paroxysmal AF using a circular-shaped multi-electrode catheter equipped with magnetic sensors for pulmonary vein isolation (PVI). METHODS AND RESULTS: A novel proprietary bipolar PFA system was used for PVI, which utilized a circular-shaped multi-electrode catheter with magnetic sensors and allowed for three-dimensional model reconstruction, mapping, and ablation in one map. To evaluate the efficacy, efficiency, and safety of this PFA system, a prospective, multi-centre, single-armed, pre-market clinical study was performed. From July 2021 to December 2022, 151 patients with paroxysmal AF were included and underwent PVI. The study examined procedure time, immediate success rate, procedural success rate at 12 months, and relevant complications. In all 151 patients, all the pulmonary veins were acutely isolated using the studied system. Pulsed field ablation delivery was 78.4 ± 41.8 times and 31.3 ± 16.7 ms per patient. Skin-to-skin procedure time was 74.2 ± 29.8 min, and fluoroscopy time was 13.1 ± 7.6 min. The initial 11 (7.2%) cases underwent procedures with deep sedation anaesthesia, and the following cases underwent local anaesthesia. In the initial 11 cases, 4 cases (36.4%) presented transient vagal responses, and the rest were all successfully preventatively treated with atropine injection and rapid fluid infusion. No severe complications were found during or after the procedure. During follow-up, 3 cases experienced atrial flutter, and 11 cases had AF recurrence. The estimated 12-month Kaplan-Meier of freedom from arrhythmia was 88.4%. CONCLUSION: The PFA system, comprised of a circular PFA catheter with magnetic sensors, could rapidly achieve PVI under three-dimensional guidance and demonstrated excellent safety with comparable effects.

Silencing CTGF/CCN2 inactivates the MAPK signaling pathway to alleviate myocardial fibrosis and left ventricular hypertrophy in rats with dilated cardiomyopathy.

Dilated cardiomyopathy (DCM) is characterized by left ventricular dilation associated with systolic dysfunction. The purpose of the current study is to clarify the effect of connective tissue growth factor (CTGF/CCN2) on myocardial fibrosis and left ventricular hypertrophy (LVH) of rats with DCM through the mitogen-activated protein kinase (MAPK) signaling pathway. First, DCM rat models were established and sh-CTGF/CCN2 lentiviral expression vectors were constructed. Then, by observing the pathological changes and myocardial ultrastructure as well as detecting cardiac functions, myocardial fibrosis, and LVH of rats, the effect of CTGF/CCN2 gene silencing on rats with DCM was investigated. To further explore how CTGF/CCN2 gene silencing affects rats with DCM, the expression of CTGF/CCN2 and the related genes of the MAPK signaling pathway was detected. Sh-CTGF/CCN2-2 and sh-CTGF/CCN2-3 with lower CTGF/CCN2 expression were selected for further experimentation. CTGF/CCN2 gene silencing improved cardiac function and alleviated myocardial fibrosis and LVH of rats with DCM. It was also verified that CTGF/CCN2 gene silencing could relieve the pathology of rats with DCM by inactivation of the MAPK signaling pathway. We conclude that CTGF/CCN2 gene silencing inhibits the activation of the MAPK signaling pathway, thus decreases myocardial fibrosis and LVH, and then improves the pathological symptoms of DCM in rats.

Teneligliptin mitigates diabetic cardiomyopathy by inhibiting activation of the NLRP3 inflammasome.

BACKGROUND: Diabetic cardiomyopathy (DCM), which is a complication of diabetes, poses a great threat to public health. Recent studies have confirmed the role of NLRP3 (NOD-like receptor protein 3) activation in DCM development through the inflammatory response. Teneligliptin is an oral hypoglycemic dipeptidyl peptidase-IV inhibitor used to treat diabetes. Teneligliptin has recently been reported to have anti-inflammatory and protective effects on myocardial cells. AIM: To examine the therapeutic effects of teneligliptin on DCM in diabetic mice. METHODS: Streptozotocin was administered to induce diabetes in mice, followed by treatment with 30 mg/kg teneligliptin. RESULTS: Marked increases in cardiomyocyte area and cardiac hypertrophy indicator heart weight/tibia length reductions in fractional shortening, ejection fraction, and heart rate; increases in creatine kinase-MB (CK-MB), aspartate transaminase (AST), and lactate dehydrogenase (LDH) levels; and upregulated NADPH oxidase 4 were observed in diabetic mice, all of which were significantly reversed by teneligliptin. Moreover, NLRP3 inflammasome activation and increased release of interleukin-1ß in diabetic mice were inhibited by teneligliptin. Primary mouse cardiomyocytes were treated with high glucose (30 mmol/L) with or without teneligliptin (2.5 or 5 µM) for 24 h. NLRP3 inflammasome activation. Increases in CK-MB, AST, and LDH levels in glucose-stimulated cardiomyocytes were markedly inhibited by teneligliptin, and AMP (p-adenosine 5'-monophosphate)-p-AMPK (activated protein kinase) levels were increased. Furthermore, the beneficial effects of teneligliptin on hyperglycaemia-induced cardiomyocytes were abolished by the AMPK signaling inhibitor compound C. CONCLUSION: Overall, teneligliptin mitigated DCM by mitigating activation of the NLRP3 inflammasome.

[Radiofrequency catheter ablation for ventricular premature beats of left coronary cusp under the guidance of 3-dimensional mapping system].

OBJECTIVE: To explore the efficacy and safety of radiofrequency catheter ablation (RCA) for ventricular premature beats originating from left coronary sinus under the guidance of 3-dimensional mapping system (CARTO). METHODS: A total of 15 patients with premature ventricular contractions (PVCs) originating from left coronary sinus underwent CARTO-guided RCA. Anatomical structures were constructed and three-dimension (3D) electrical activation sequence was plotted for left ventricle and aortic sinus. The distance of earliest activation point of PVCs and origin of left coronary artery were surveyed after left coronary arteriography. RESULTS: The electrocardiogram (ECG) results showed that R-wave was upward in leads II, III and avF, QRS waves in lead I was mainly of rS, rs and rsr types, QS type in lead avL, RS, Rs and rS type in lead V(1), RS type in lead V(3) and absence of S wave in lead V(5)/V(6). Intraoperative mapping detected the earliest activation point on the posterior-inferior origin of left coronary artery (LMCA) ostium (n = 7), on the anterio-inferior of LMCA ostium (n = 3) and on the inferior of LMCA ostium (n = 5). The earliest activation point (local activation time) was shorter 86 - 120 ms than surface electrocardiogram QRS wave, discharge melting on the earliest activation point and nearby succeeded. PVCs disappeared, PVCs failed to be induced under similar preoperative conditions (aleudrin intravenous) and no complication occurred intraoperatively and postoperatively. CONCLUSION: The CARTO-guided RCA is a safe and effective in the treatment of PVCs originating from left coronary sinus.

[Comparative study of interventricular electrical and mechanical synchrony at different cardiac pacing sites].

OBJECTIVE: To compare the different impacts of right ventricular apex, right ventricular outflow tract septum and left ventricular outflow tract septum region on interventricular electro-mechanical synchronization and assess the ideal pacing sites for maintaining the interventricular electro-mechanical synchronization. METHODS: A total of 30 patients without organic heart disease were operated with radiofrequency ablation at our hospital. The mapping electrodes were implanted post-operatively on the left ventricular posterior wall (LVPLW) and right ventricular anterior lateral wall (RVALW) respectively. And the ablation electrodes were placed subsequently in right ventricular apex, right ventricular outflow tract septum region and left ventricular outflow tract septum. The difference values were measured between transmission time from pacemaker to LVPLW, from pacemaker to RVALW and between aortic pre-ejection interval (APEI) and pulmonary artery pre-ejection interval (PPEI). Then their correlations were compared. RESULTS: When pacing at right ventricular apex, the difference value between transmission time from pacemaker to LVPLW and from pacemaker to RVALW was (34 ± 7) ms. And it was (18 ± 4) ms while pacing at right ventricular outflow tract septum region and (12 ± 4) ms at left ventricular outflow tract septum region. There was significant difference (P < 0.01). The absolute value of APEI-PPEI was (25 ± 5) ms at right ventricular apex, (13 ± 4) ms at right ventricular outflow tract septum region and (11 ± 3) ms at left ventricular outflow tract septum region. And there was significant difference (P < 0.01). The absolute value of APEI-PPEI was positively correlated with the change of LVPLW-RVALW (r = 0.993, P < 0.01). Left ventricular outflow tract septum pacing showed ABp and left ventricle end-systolic pressure significantly increased [(127 ± 23) mm Hg, (142 ± 22) mm Hg, P < 0.05], left ventricular end-diastolic pressure was significantly lower [(9 ± 3) mm Hg, P < 0.05]. CONCLUSION: Compared with right ventricular apical pacing and right ventricular outflow tract ventricular septal pacing, left ventricular outflow tract septum has a smaller impact on the electro-mechanical synchronization. It conforms more closely to the physiological pacing so that there is a higher synchronization of electrical and mechanical ventricular contractions.

[Percutaneous coronary intervention of patients with complex small coronary artery lesion unsuitable for coronary artery bypass graft].

OBJECTIVE: To investigate the safety and efficacy of percutaneous coronary intervention (PCI) in patients with low left ventricular ejection fraction (LVEF) and complex small coronary artery lesions. METHODS: Complete or partial post-PCI revascularization of coronary artery was employed in 16 patients with a low LVEF and complex small coronary artery lesions who were unsuitable for CABG (coronary artery bypass grafting). All cases were observed with regards to immediate success rate of operation, complication, hospitalization duration, improvement of cardiac function and LVEF and major adverse cardiac events (including cardiac death, myocardial infarction and target lesion revascularization) at 12 months post-operation. RESULTS: All cases were successfully treated without death and severe complications while the hospitalization duration was (11 +/- 5) days. The follow-up survey at 12 months post-operation showed that no major adverse cardiac event occurred, the post-operative improvement of cardiac function was from III - IV grade to I - II grade, the improvement of LVEF was from 25% - 45% [(29 +/- 8)%] to 32% - 48% [(37 +/- 7)%], left ventricular end diastolic diameter (LVDd) was shortened from 52 - 79 (66 +/- 11) mm to 49 - 68 (58 +/- 8) mm. The reexamination of 14 cases by coronary angiography at 12 months post-operation showed that there was no intra-stent thrombosis while 20% - 40% intra-stent restenosis occurred in 2 cases. CONCLUSION: For patients with a low LVEF and complex small coronary artery lesions, PCI is a safe and effective method to lower the mortality rate of CHD patients with heart failure and improve the long-term patient prognosis.

Application of percutaneous balloon mitral valvuloplasty in patients of rheumatic heart disease mitral stenosis combined with tricuspid regurgitation.

BACKGROUND: Tricuspid regurgitation (TR) is frequently associated with severe mitral stenosis (MS), the importance of significant TR was often neglected. However, TR influences the outcome of patients. The aim of this study was to investigate the efficacy and safety of percutaneous balloon mitral valvuloplasty (PBMV) procedure in rheumatic heart disease patients with mitral valve (MV) stenosis and tricuspid valve regurgitation. METHODS: Two hundred and twenty patients were enrolled in this study due to rheumatic heart disease with MS combined with TR. Mitral balloon catheter made in China was used to expand MV. The following parameters were measured before and after PBMV: MV area (MVA), TR area (TRA), atrial pressure and diameter, and pulmonary artery pressure (PAP). The patients were followed for 6 months to 9 years. RESULTS: After PBMV, the MVAs increased significantly (1.7 ± 0.3 cm 2 vs. 0.9 ± 0.3 cm 2 , P < 0.01); TRA significantly decreased (6.3 ± 1.7 cm 2 vs. 14.2 ± 6.5 cm 2 , P < 0.01), right atrial area (RAA) decreased significantly (21.5 ± 4.5 cm 2 vs. 25.4 ± 4.3 cm 2 , P < 0.05), TRA/RAA (%) decreased significantly (29.3 ± 3.2% vs. 44.2 ± 3.6%, P < 0.01). TR velocity (TRV) and TR continue time (TRT) as well as TRV × TRT decreased significantly (183.4 ± 9.4 cm/s vs. 254.5 ± 10.7 cm/s, P < 0.01; 185.7 ± 13.6 ms vs. 238.6 ± 11.3 ms, P < 0.01; 34.2 ± 5.6 cm vs. 60.7 ± 8.5 cm, P < 0.01, respectively). The postoperative left atrial diameter (LAD) significantly reduced (41.3 ± 6.2 mm vs. 49.8 ± 6.8 mm, P < 0.01) and the postoperative right atrial diameter (RAD) significantly reduced (28.7 ± 5.6 mm vs. 46.5 ± 6.3 mm, P < 0.01); the postoperative left atrium pressure significantly reduced (15.6 ± 6.1 mmHg vs. 26.5 ± 6.6 mmHg, P < 0.01), the postoperative right atrial pressure decreased significantly (13.2 ± 2.4 mmHg vs. 18.5 ± 4.3 mmHg, P < 0.01). The pulmonary arterial pressure decreased significantly after PBMV (48.2 ± 10.3 mmHg vs. 60.6 ± 15.5 mmHg, P < 0.01). The symptom of chest tightness and short of breath obviously alleviated. All cases followed-up for 6 months to 9 years (average 75 ± 32 months), 2 patients with severe regurgitation died (1 case of massive cerebral infarction, and 1 case of heart failure after 6 years and 8 years, respectively), 2 cases lost access. At the end of follow-up, MVA has been reduced compared with the postoperative (1.4 ± 0.4 cm 2 vs. 1.7 ± 0.3 cm 2 , P < 0.05); LAD slightly increased compared with the postoperative (45.2 ± 5.7 mm vs. 41.4 ± 6.3 mm, P < 0.05), RAD slightly also increased compared with the postoperative (36.1 ± 6.3 mm vs. 28.6 ± 5.5 mm, P < 0.05), but did not recover to the preoperative level. TRA slightly increased compared with the postoperative, but the difference was not statistically significant (P > 0.05). The PAP and left ventricular ejection fraction appeared no statistical difference compared with the postoperative (P > 0.05), the remaining patients without serious complications. CONCLUSIONS: PBMV is a safe and effective procedure for MS combined with TR in patients of rheumatic heart disease. It can alleviate the symptoms and reduce the size of TR. It can also improve the quality-of-life and prognosis. Its recent and mid-term efficacy is certain. While its long-term efficacy remains to be observed.

Application of peripheral-blood-derived endothelial progenitor cell for treating ischemia-reperfusion injury and infarction: a preclinical study in rat models.

BACKGROUND: Our aim was to explore the therapeutic effects of peripheral blood-derived endothelial progenitor cells (PB-EPC) in cardiac ischemia-reperfusion infarction models in rats and in in vitro culture systems. METHODS: Rat models of ischemia reperfusion and myocardial infarction were developed using male, Sprague-Dawley rats. Cardiomyocyte and endothelial cell cultures were also established. Therapeutic effects of PB-EPCs were examined in vivo and in vitro in both models. Rats underwent either cardiac ischemia-reperfusion (n = 40) or infarction (n = 56) surgeries and were transplanted with genetically modified EPCs. Treatment efficacy in the ischemia-reperfusion group was measured by infarct size, myocardial contraction velocity, and myeloperoxidase activity after transplantation. Cardiomyocyte survival and endothelial cell apoptosis were investigated in vitro. Vascular growth-associated protein expression and cardiac function were evaluated in the myocardial infarction group by western blot and echocardiography, respectively. RESULTS: Infarct size and myeloperoxidase activity were significantly decreased in the ischemia-reperfusion group, whereas myocardial contractility was significantly increased in the EPC and Tß4 groups compared with that in the control group. In contrast, no differences were found between EPC + shRNA Tß4 and control groups. Rates of cardiomyocyte survival and endothelial cell apoptosis were significantly higher and lower, respectively, in the EPC and Tß4 groups than in the control group, whereas no differences were found between the EPC + shRNA Tß4 and control group. Four weeks after myocardial infarction, cardiac function was significantly better in the EPC group than in the control group. Expressions of PDGF, VEGF, and Flk-1 were significantly higher in EPC group than in control group. CONCLUSIONS: Study findings suggest that PB-EPCs are able to protect cardiomyocytes from ischemia-reperfusion or infarction-induced damage via a Tß4-mediated mechanism. EPCs may also provide protection through increased expression of proteins involved in mediating vascular growth. Autologous peripheral-blood-derived EPCs are readily available for efficient therapeutic use without the concerns of graft rejection.