Predictive value of impedance of leadless pacemaker during implantation on trend changes of pacing threshold / 中华心血管病杂志

Objective: To explore the predictive value of the impedance measured during leadless pacemaker Micra implantation on the trend of changes of pacing threshold post implantation. Methods: This is a retrospective cross-sectional study. Patients who received implantation of leadless pacemaker Micra at the Second Xiangya Hospital of Central South University from December 2019 to August 2020 were enrolled. The clinical data and the intraoperative electrical parameters during leadless pacemaker implantation were collected. The impedance and pacing threshold data were analyzed at three time points: immediate release, 5-10 min after release, and after traction test. Receiver operating characteristic (ROC) curves and the area under the curve (AUC) were used to analyze the value of the impedance at immediate release on predicting the trend of changes of pacing threshold post implantation. Results: A total of 21 patients (mean age: (72.2±12.5) years, 12 males) were included. The impedance of 21 patients was (798.1±35.3) Ω immediately after implantation, (800.9±35.6) Ω after 5-10 minutes of release, and (883.6±31.7) Ω after traction test. Impedance was similar between the three time points (P>0.05). The threshold was (0.97±0.11) V/0.24 ms immediately after implantation, (0.95±0.12) V/0.24 ms at 5-10 min after the release, and (0.59±0.06) V/0.24 ms after the traction test. The threshold was significantly lower after the traction test than that immediately after release (P=0.003) and than that at 5-10 minutes after release (P=0.008), suggesting a decreased tendency of the threshold over time. According to the analysis of the ROC curve, the immediate impedance after the release ≥680 Ω could predict the ideal pacing threshold after the traction test (AUC=0.989, 95%CI 0.702-0.964, P<0.001), the prediction sensitivity was 87%, and the specificity was 100%. The pacing threshold would be not ideal with the immediate impedance ≤ 520 Ω (95%CI 0.893-1.000, P<0.001), the sensitivity was 100%, and the specificity was 80%. Conclusions: The impedance immediately after the release has predictive value for the changing trend of threshold post leadless pacemaker Micra implantation. Impedance ≥680 Ω immediately after release is often related with ideal pacing threshold after the traction test. In contrast, the impedance ≤ 520 Ω pacing is often related with unsatisfactory threshold after the traction test, therefore, it is recommended to find a new pacing site to achieve the impedance ≥680 Ω immediately after release during leadless pacemaker Micra implantation.

Comparative outcomes of subcutaneous and transvenous cardioverter-defibrillators / 中华医学杂志(英文版)

BACKGROUND@#The comparative outcomes of subcutaneous implantable cardioverter-defibrillator (S-ICD) and transvenous ICD (T-ICD) have not been well studied. The aim of this study was to evaluate the safety and efficacy of currently available S-ICD and T-ICD.@*METHODS@#The study included 86 patients who received an S-ICD and 1:1 matched to those who received single-chamber T-ICD by gender, age, diagnosis, left ventricular ejection fraction (LVEF), and implant year. The clinical outcomes and implant complications were compared between the two groups.@*RESULTS@#The mean age of the 172 patients was 45 years, and 129 (75%) were male. The most common cardiac condition was hypertrophic cardiomyopathy (HCM, 37.8%). The mean LVEF was 50%. At a mean follow-up of 23 months, the appropriate and inappropriate ICD therapy rate were 1.2% vs. 4.7% (χ = 1.854, P = 0.368) and 9.3% vs. 3.5% (χ = 2.428, P = 0.211) in S-ICD and T-ICD groups respectively. There were no significant differences in device-related major and minor complications between the two groups (7.0% vs. 3.5%, χ = 1.055, P = 0.496). The S-ICD group had higher T-wave oversensing than T-ICD group (9.3% vs. 0%, χ = 8.390, P = 0.007). Sixty-five patients had HCM (32 in S-ICD and 33 in T-ICD). The incidence of major complications was not significantly different between the two groups.@*CONCLUSIONS@#The efficacy of an S-ICD is comparable to that of T-ICD, especially in a dominantly HCM patient population. The S-ICD is associated with fewer major complications demanding reoperation.

Treatment of pulmonary sinus cusp-derived ventricular arrhythmia with reversed U-curve catheter ablation / 中国介入心脏病学杂志

Objective To summarize the ablation methods,and to provide experience reference for the treatment of pulmonary since cusp(PSC)-derived ventricular arrhythmia(VA)with ablation. Methods A retrospective analysis of the clinical data of 19 patients undergoing catheter ablation for PSC-derived VA in Cardiac Intervention Therapy Center,The Second Xiangya Hospital of Central South University between January 2013 and March 2016 was conducted. Results Among the 19 patients,PSC-derived VA originated from the lower regions of the pulmonary sinuses,generating from the right,left,and anterior sinuses of the PSC were identified in 5,7,and 7 patients,respectively. Twelve patients with PSC-derived VAs originating from the right and anterior sinuses underwent successful reversed U-curve catheter ablation,while the other 7 patients with arrhythmias originating from the left sinus underwent successful ablation with the conventional method(non-reversed U-curve catheter ablation). All the patients were followed-up for 6 to 31 months,and no recurrence of VA or complications were recorded. Conclusions Reversed U-curve catheter ablation is suitable for VA originating from the right and anterior PSCs,while conventional ablation can be used for those originating from the left PSCs.

Prevalence and risk factors of peri-procedure electrical storm in acute myocardial infarction patients underwent emergency percutaneous coronary intervention / 中华心血管病杂志

<p><b>OBJECTIVE</b>To determine the prevalence and to identify risk factors of peri-procedure electrical storm (ES) in patients with acute myocardial infarction (AMI) underwent emergency percutaneous coronary intervention (PCI).</p><p><b>METHODS</b>The clinical data of 228 AMI patients underwent emergency PCI were retrospectively analyzed and patients were divided into ES group (n = 39) and non-ES (n = 189) group. ES was referred to spontaneous ventricular tachycardia or ventricular fibrillation occurring twice or more within 24 h and requiring emergency treatment including anti-arrhythmic medicine and/or cardioversion or defibrillation.</p><p><b>RESULTS</b>ES was diagnosed in 39 out of 228 patients (17.1%) during peri-procedure stage. The incidence of ES in patients with various infarct related arteries (IRA) was as follows: 55.6% with left main artery (LM), 23.7% with right coronary artery (RCA), 12.4% with anterior descending branch (LAD) and 0 with left circumflex artery (LCX). Older age, lager diameter of IRA, higher concentration of CK-MB and cTnT, higher incidence of reperfusion arrhythmia (RA), lower grade of TIMI after PCI and higher mortality were associated with increased risks of ES (The P value was 0.043, 0.012, 0.036, 0.018, 0.001, 0.049, respectively). Gender, systolic pressure, diastolic pressure, random blood glucose level, white blood count and concentration of hs-CRP were similar between ES and non-ES patients. Logistic analysis showed that the diameter of IRA (OR 2.381, 95%CI 1.127-5.028, P = 0.023), TIMI grade of IRA after PCI (OR 4.744, 95% CI 1.773-12.691, P = 0.002) and RA (OR 12.680, 95% CI 4.360-36.879, P = 0.000) were the independent risk factors of per-procedure ES in AMI patients underwent emergency PCI.</p><p><b>CONCLUSIONS</b>The AMI patients with LM as IRA had the highest incidence of ES during emergency PCI and the diameter of IRA, TIMI grade of IRA after PCI and RA were independent risk factors for the development of ES during peri-PCI stage.</p>

Changes of plasma CD40L and PAPP-A in patients with acute coronary syndrome after the PCI operation / 中南大学学报(医学版)

OBJECTIVE@#To observe the changes and significance of plasma CD40L and pregnancy-associated plasma protein-A (PAPP-A) in acute coronary syndrome (ACS) patients after percutaneous coronary intervention (PCI) operation.@*METHODS@#According to the occurrence of primary heart events or restenosis 6 months after the PCI, 68 patients were divided into the ACS group and the stable angina pectoris (SAP) group. Plasma CD40L and PAPP-A after the PCI operation were measured and compared. Thirty-six patients underwent repeated angiography after the PCI. Their baseline and follow up angiograms were compared by quantitative coronary angiography to assess the incidence of restenosis.@*RESULTS@#CD40L and PAPP-A after the PCI operation were higher in the ACS group than that in the SAP group.The group having primary heart events within 6 months had higher level of PAPP-A after the PCI. The group having restenosis 6 months had higher level of PAPP-A after the PCI. The change of later loss index of coronary artery lumen diameter was correlated with PAPP-A level after the PCI.@*CONCLUSION@#CD40L and PAPP-A were higher in the ACS group, indicating the possible mechanism by which CD40L facilitates the plaque rupture via up-regulating the PAPP-A expression.Plasma PAPP-A level after the PCI possibly for cases the occurrence of primary heart events or restenosis within 6 months.

Peripheral vascular complications after the cardiac catheterization / 中南大学学报(医学版)

OBJECTIVE@#To explore the cause, the clinical manifestation and the management of peripheral vascular complications after cardiac catheterization.@*METHODS@#Clinical data of patients with peripheral vascular complications were analyzed retrospectively.@*RESULTS@#Of the 4,531 patients, 122 (2.7%) had peripheral vascular complications, including local hematoma (86 cases, 1.90%), pseudoaneurysm (15 cases, 0.33%), arteriovenous fistula (8 cases, 0.18%), femoral venous thrombosis (5 cases, 0.11%), excessive hemorrhage (5 cases, 0.11%), femoral arterial thrombosis (2 cases, 0.04%), and femoral nerve malfunction (1 case, 0.02%). All complications were relieved after conservative therapy except that one case needed surgery.@*CONCLUSION@#Peripheral vascular complications are associated with anticoagulation, diabetes, and hypertension. Prognosis of overwhelming complications is good, as long as patients are treated timely and appropriately.

Oxidative stress and inflammation with angiographic morphology of coronary lesions in patients with coronary heart disease / 中南大学学报(医学版)

OBJECTIVE@#To evaluate the role of oxidative stress and inflammation in the development of plaque rupture.@*METHODS@#One hundred and ten patients enrolled in this study. All patients underwent coronary angiography. It included 85 patients with coronary heart disease (CHD) and 25 controls. The angiographic morphology of plaques was analyzed. According to the morphologic types of plaque, CHD patients were divided into Type I (smooth borders) group (n=31), Type II (irregular lesions) group (n=35), and Type III (long lesions) group (n=19). All patients were measured of MDA-LDL, hs-CRP, creatine kinase (CK), and MB isoenzyme of CK (CK-MB) in the plasma.@*RESULTS@#Plasma MDA-LDL and hs-CRP in the Type II group were significantly higher than those in the control group, Type I group, and Type III group (P0.05). The plasma levels of MDA-LDL and hs-CRP had a significant positive correlation in patients in Type II group (r=0.630, P<0.01).@*CONCLUSION@#Oxidative stress and inflammation may cause plaque rupture in CHD patients. The oxidative stress is likely to either induce or intensify the inflammatory action, and may co-affect with inflammation factors to cause or accelerate plaque rupture.

Epigallocatechin gallate protects dopaminergic neurons against 1-methyl-4- phenyl-1,2,3,6-tetrahydropyridine-induced neurotoxicity by inhibiting microglial cell activation / 南方医科大学学报

<p><b>OBJECTIVE</b>To observe whether the dopaminergic neuroprotective effect of (-)-epigallocatechin gallate (EGCG) is associated with its inhibition of microglial cell activation in vivo.</p><p><b>METHODS</b>The effects of EGCG at different doses on dopaminergic neuronal survival were tested in a methyl-4-phenyl-pyridinium (MPP+)-induced dopaminergic neuronal injury model in the primary mesencephalic cell cultures. With unbiased stereological method, tyrosine hydroxylase-immunoreactive (TH-ir) cells were counted in the A8, A9 and A10 regions of the substantia nigra (SN) in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-treated C57BL/6 mice. The effect of EGCG on microglial activation in the SN was also investigated.</p><p><b>RESULTS</b>Pretreatment with EGCG (1 to 100 micromol/L) significantly attenuated MPP+-induced TH-ir cell loss by 22.2% to 80.5% in the mesencephalic cell cultures. In MPTP-treated C57BL/6 mice, EGCG at a low concentration (1 mg/kg) provided significant protection against MPTP-induced TH-ir cell loss by 50.9% in the whole nigral area and by 71.7% in the A9 region. EGCG at 5 mg/kg showed more prominent protective effect than at 1 or 10 mg/kg. EGCG pretreatment significantly inhibited microglial activation and CD11b expression induced by MPTP.</p><p><b>CONCLUSION</b>EGCG exerts potent dopaminergic neuroprotective activity by means of microglial inhibition, which shed light on the potential use of EGCG in treatment of Parkinson's disease.</p>

Drinking behavior and c-fos expression induced by chemical or electrical stimulation of SFO in rat brain / 中国应用生理学杂志

<p><b>AIM</b>To compare the drinking behavior and c-fos expression induced by chemical or electrical stimulation of subfornical organ (SFO) in rat brain.</p><p><b>METHODS</b>L-glutamic acid microinjection and constant electrical current were used as chemical and electrical stimulation of SFO, respectively. The water intake over 1 h was recorded and Fos expression was examined immunohistochemically.</p><p><b>RESULTS</b>A similar volume of water intake and Fos expression pattern were induced by both methods of stimulation of SFO. These include 11 forebrain areas (organum vasculosum of the lamina terminalis, median preoptic nucleus, hypothalamic paraventricular nucleus, supraoptic nucleus and lateral hypothalamic area, paraventricular nucleus, reunions nucleus and central medial nucleus of thalamus, bed nucleus of the stria terminalis, perifornical dorsal area and substantia innominata) and 4 areas of hindbrain (area postrema, nucleus solitary tract, lateral parabrachial nucleus and dorsal raphe nucleus).</p><p><b>CONCLUSION</b>The drinking behavior and Fos expression in brain induced by SFO stimulation are the results of activation of the neuronal bodies in SFO.</p>