2005年 · 第118卷第14期

In the past decade, there is a great progress in the treatment of atrial fibrillation (AF) by transcatheter ablation. The catheter-based procedures have developed from Maze-like linear lesion, focal lesion to segmental electrical isolation of pulmonary veins and circumferential ablation under guidance of anatomical mapping, ablation energy developed from radiofrequency to multiple energy such as radiofrequency, ultrasound and cryoablation; and success rate has risen to 90% from around 30% in the past.1 Catheter ablation has been widely accepted as a treatment of AF and tends to substitute pharmacological therapy and become first-line treatment gradually. It must point out that, however, catheter ablation of AF is not perfect and there are many issues desiderating resolution。

Abstract：Background Delayed cure had been observed in recurrent cases after index ablation of atrial fibrillation (AF), however, its mechanism and incidence have not been elucidated in detail. This study aims to investigate the impact of different ablation strategies on the incidence of delayed cure and its possible mechanisms after trans-catheter ablation of AF. Methods One hundred and fifty-one consecutive cases with highly symptomatic, drug refractory AF were included in this study [M/F=109/42, mean age (56.0±11.2) (18-79) years]. Segmental pulmonary vein ablation (SPVA) was performed in 83 patients with the guidance of circular mapping catheter (SPVA Group), circumferential PV linear ablation (CPVA) was carried out in the rest 68 cases under the guidance of 3 dimensional mapping system in conjunction with circular mapping catheter (CPVA Group). Delayed cure was defined as that early recurrence of atrial tachyarrhythmias (AF, atrial tachycardia, or atrial flutter) after ablation procedure was no longer observed during subsequent follow-up, and stable sinus rhythm was maintained ≥2 months. Results Early recurrence of atrial tachyarrhythmias was detected in 41 cases from SPVA group and 23 cases from CPVA group, and delayed cure occurred in 21.9% (9/41) of the cases from SPVA group and 47.8% (11/23) of the cases from CPVA group, more delayed cure in later group was observed (P<0.05). Meanwhile, patients in SPVA group took a longer time to achieve a delayed cure [(27.0±18.0) days vs (14.0±8.1) days, P<0.05], and presented more recurrent episodes [(3.50±1.08) times a week vs (2.42±1.11) times a week, P<0.05]. However, recurrent episodes after index ablation were markedly decreased in cases with delayed cure from both groups (P<0.05). Conclusions Despite of an early recurrence of atrial tachyarrhythimas after index ablation of AF, delayed cure occurs in a significant number of patients undergoing either SPVA or CPVA. However, different ablation strategies place different impact on the delayed cure, more delayed cure is obtained with CPVA approach, and the delayed cure occurs earlier with this approach; the average recurrent episodes before delayed cure are also less frequently detected in CPVA group compared with those in SPVA group。

Abstract：Background The circumferential pulmonary vein ablation (CPVA) has been proved effective for atrial fibrillation (AF) treatment and is becoming more widely accepted and practiced. This study aims to evaluate the characteristics of the CARTO and the Ensite/NavX system and draw a comparison between them on the aspects of procedural parameters and clinical effectiveness.Methods Seventy-five cases with paroxysmal or chronic symptomatic AF were randomly assigned to CPVA procedure guided by the Ensite/NavX system (group Ⅰ, n=40) and by the CARTO system (group Ⅱ, n=35). After successful transseptal procedure, the geometry of left atrium was created under the guidance of the two systems. Radiofrequency energy was applied to circumferentially ablate tissues out of pulmonary veins' (PVs') ostia. In cases with chronic AF, linear ablation was applied to modify the substrate of left atrium (LA). The endpoint of the procedure was complete PVs isolation. Results Seventy-five cases underwent the procedure successfully. The total procedure and fluoroscopic durations in group Ⅱ were significantly shorter than in group Ⅰ [(150±23) min and (18±17) min versus (170±34) min and (25±16) min, P=0.03 and 0.04, respectively]. There was no significant difference in the fluoroscopic and procedure durations for geometry creation between group Ⅰ and group Ⅱ [(8±4) min and (16±11) min versus (5±4) min and (14±8) min, respectively]. The fluoroscopic durations for CPVA were (15±5) min in group Ⅰ versus (10±6) min in group Ⅱ (P=0.05), and the CPVA procedural durations were significantly shorter in group Ⅱ than in group Ⅰ [(18±11) min versus (25±10) min, P=0.04]. AF was terminated by radio frequency delivery in 14 cases (35%) in group Ⅰ versus 5 cases (14%) in group Ⅱ (P=0.035). After CPVA complete PV isolation was attained in 26 cases (65%) in group Ⅰ versus 11 cases (31%) in group Ⅱ (P=0.004). During a mean follow-up of 7 months, 32 (80%) cases in group Ⅰ and 24 (69%) cases in group Ⅱ were arrhythmia-free (P=0.06). One case developed pericardium effusion and another one case was found to have intestinal artery thrombosis in group Ⅱ. One case had moderate hemothorax in group Ⅰ. All the complications were cured by proper treatment. No PV stenosis was observed. Conclusions The CPVA procedure for atrial fibrillation is effective and safe. Although there is difference between the CARTO and the Ensite/NavX system, the CPVA procedure guided by either of them yields similar clinical results。

Abstract：Background Atrial fibrillation (AF) is the most common supraventricular arrhythmia in clinical practice. Chronic atrial fibrillation (CAF) is associated with ionic remodeling. However, little is known about the activity of ATP-sensitive potassium current (IK,ATP) during CAF. So we studied the changes of IK,ATP density and allosteric modulation of ATP-sensitivity by intracellular pH during CAF.Methods Myocardium samples were obtained from the right auricular appendage of patients with rheumatic heart disease complicated with valvular disease in sinus rhythm (SR) or CAF. There were 14 patients in SR group and 9 patients in CAF group. Single atrial cells were isolated using an enzyme dispersion technique. IK,ATP was recorded using the whole-cell and inside-out configuration of voltage-clamp techniques. In whole-cell model, myocytes of SR and CAF groups were perfused with simulated ischemic solution to elicit IK,ATP. In inside-out configuration, the internal patch membranes were exposed to different ATP concentrations in pH 7.4 and 6.8.Results Under simulated ischemia, IK,ATP current density of CAF group was significantly higher than in SR group [(83.5±10.8) vs. (58.7±8.4) pA/pF, P<0.01]. IK,ATP of the two groups showed ATP concentration-dependent inhibition. The ATP concentration for 50% current inhibition (IC50) for the SR group was significantly different in pH 7.4 and pH 6.8 (24 vs. 74 μmol/L, P<0.01). The IC50 did not change significantly in CAF group when the pH decreased from 7.4 to 6.8.Conclusions During CAF, IK,ATP current density was increased and its allosteric modulation of ATP-sensitivity by intracellular pH was diminished。

Abstract：Background The oxidative modification of low-density lipoprotein in the artery wall is currently believed to be central to the pathogenesis of atherosclerosis. Paraoxonase (PON1), an enzyme located on high-density lipoprotein (HDL), can prevent low-density lipoprotein (LDL) from oxidation at a certain extent. Recent studies show two other members of paraoxonase gene family, PON2 and PON3, possess antioxidant properties similar to PON1. The aim of the present study was to explore the role of PON gene cluster on coronary heart disease (CHD) in Chinese Han women.Methods Seven polymorphisms including PON1 -107C>T, -162G>A, -831G>A, R160G, Q192R, PON2 S311C, and PON3 -133C>A were genotyped in 184 female patients with CHD and 239 female controls. The plasma PON1 activity toward phenylacetate was determined in 50 cases and 50 controls randomly selected. Results The plasma PON1 activities were significantly lower in cases than in controls. Individual SNP analysis showed that cases had significantly higher frequencies of PON1 -107T, -831G and PON2 311S alleles than controls. The genotype distributions of -107C>T were also significantly different between two groups. The odds ratios for the development of CHD were 1.66 for -107TC carriers and 2.0 for -107TT carriers, compared with -107CC carriers. Haplotype analyses showed that the distributions of haplotypes comprised of PON1 -107C>T and PON2 S311C were significantly different between cases and controls, with cases having higher frequency of T-S haplotype (44.8% vs. 36.3%, P=0.013). The T-S haplotype remained significantly associated with CHD after adjusting environmental risk factors (P=0.0069).Conclusions This association study suggested that lower plasma PON1 activity increased the risk of CHD in Chinese woman, which may be mediated by the higher frequency of -107T allele in cases. Haplotype analyses indicated that there might be some synergistic effects between the PON1 -107C>T and PON2 S311C polymorphisms。

Abstract：Background Emerging evidence suggests that stem cells can be used to improve cardiac function in patients after acute myocardial infarction. In this randomized trial, we aimed to use Doppler tissue tracking and strain imaging to assess left ventricular segmental function after intracoronary transfer of autologous bone-marrow stem cells (BMCs) for 6 months' follow up. Methods Twenty patients with acute myocardial infarction and anterior descending coronary artery occlusion proven by angiography were double-blindedly randomized into intracoronary injection of bone-marrow cell (treated, n=9) or diluted serum (control, n=11) groups. GE vivid 7 and Q-analyze software were used to perform echocardiogram in both groups 1 week, 3 months and 6 months after treatment. Three apical views of tissue Doppler imaging were acquired to measure peak systolic displacement (Ds) and peak systolic strain (εpeak) from 12 segments of LV walls. Left ventricular ejection fraction (LVEF), end-diastolic volume (EDV) and end-systolic volume (ESV) were obtained by Simposon's biplane method. Results (1) 3 months later, Ds and εpeak over the infract-related region clearly increased in the BMCs group [Ds: (4.49±2.71) mm vs (7.56±2.95) mm, P<0.01; εpeak: (-13.40±6.00)% vs (-17.06±6.05)%, P<0.01], but not in the control group [Ds: (4.74±2.67) mm vs (5.01±3.23) mm, P>0.05; εpeak : (-13.84±6.05)% vs (-15.04±6.75)%, P>0.05]. At the same time, Ds over the normal region also increased, but the Ds enhancement was markedly higher in the BMCs group than that in the control group [(3.21±3.17) mm vs (0.76±1.94) mm, P<0.01]. Parameters remained steady from the 3rd to 6th month in either group (P>0.05). (2) LVEF in treated and control groups were almost the same at baseline (1st week after PCI) [(53.37±8.92)% vs (53.51±5.84)%, P>0.05]. But 6 months later, LVEF in the BMCs group were clearly higher than that in the control group [(59.33±12.91)% vs (50.30±8.30)%, P<0.05]. (3)There were no evident difference in EDV or ESV between two groups at baseline [EDV:(113.74±23.24) ml vs (129.94±32.72) ml , P>0.05; ESV: (57.12±18.66) ml vs (62.09±17.68) ml, P>0.05]. Three months later, EDV and ESV in the control group were markedly greater than those in the BMCs group [EDV: (154.89±46.34) ml vs (104.85±33.21) ml, P<0.05; ESV :(82.91±35.79) ml vs (49.54±23.32) ml, P<0.05]. But EDV and ESV did not change much from 3rd to 6th month in either group (P>0.05). Conclusions Emergency transplantation of autologous BMCs in patients with acute myocardial infarction helps to improve global and regional contractility and attenuate post-infarction left ventricular remodeling. Tissue tracking and strain imaging provide quick, simple and noninvasive methods for quantifying left ventricular segmental function in humans。

Abstract：Background Enhanced external counterpulsation (EECP) has been demonstrated to be effective in the treatment of patients with coronary artery disease (CAD). It has been proposed that the beneficial effects of EECP observed in clinical studies may be due to the formation of new blood vessels (angiogenesis) and collateral development. However, there is a relative paucity of basic studies to support the proposed mechanisms. Methods Twelve Beagle dogs were anesthetized with 3% sodium pentobarbital, 1 mg/kg intraperitoneal injection and mechanically ventilated for the development of myocardial infarction. After coronary occlusion, all animals were randomly assigned to either EECP or control. EECP was given one hour per day, 5 days a week, for a total of 28 to 30 hours treatment over a 6-week course. Immunohistochemical studies of α-actin and von Willebrand factor (vWF) were used to detect newly developed microvessels. Systemic and local vascular endothelial growth factor (VEGF) were identified by enzyme linked immunosorbent assay (ELISA) and reverse-transcriptional polymerase chain reaction (RT-PCR) analysis. Results There was a significant increase in the density of microvessels per mm2 in the infarcted regions of EECP group compared to control group (vWF, 15.2±6.3 versus 4.9±2.1, P<0.05; α-actin, 11.8±5.3 versus 3.4±1.2, P<0.05), along with significant increase of positive vWF and α-actin stained area. Both immunohistochemical staining and RT-PCR analysis documented a significant increase in VEGF expression. These factors associated with angiogenesis corresponded to improved myocardial perfusion by 99mTc-sestamibi single-photon emission computed tomography. Conclusion Microvessel angiogenesis may be a mechanism of action for the improved myocardial perfusion after EECP therapy。

Abstract：Background Awareness under general anesthesia is a serious complication which leads to psychiatric disorders. The incidence of awareness in patients undergoing cardiac surgery has been reported in as many as 1.5%-23% in foreign countries. But so far, medical literature about awareness during cardiac surgery is still rare in China. Therefore, we investigated the incidence of awareness in patients undergoing different kinds of cardiac surgery, the phases when awareness occured and the effect of cardiopulmonary bypass on the incidence of awareness in coronary artery bypass grafting in Beijing.Methods Patients' recall of awareness during cardiac surgery was assessed. One hundred patients undergoing coronary artery bypass grafting (CABG) in Chaoyang Hospital, Beijing, one hundred patients undergoing CABG and one hundred patients undergoing valve replacement or septal defect repair in Fuwai Hospital, Beijing, were interviewed 3-6 days after surgery. Every report obout patients on recall of awareness was recorded. An independent research team, blinded to patients' surgery and anesthesia, assessed every report of awareness.Results The incidence of awareness of patients received CABG under cardiopulmonary bypass (CPB), off -pump CABG, septal repair or valve replacement under CPB was 4.7% (5 of 106 cases), 9.6% (9 of 94 cases) and 4% (4 of 100 cases), respectively. CPB did not greatly affect the incidence of awareness during the period of CABG (P>0.05). The incidence of awareness of patients who received CABG under CPB did not increase significantly, in comparison with that of patients who received septal repair or valve replacement under CPB in Fuwai Hospital (P>0.05). Awareness easily occurred before bypass grafting or CPB.Conclusions Awareness mainly occurs before bypass grafting or CPB in cardiac surgery. Most cases with awareness have auditory perceptions. CPB is not a main factor which affects the incidence of awareness of CABG. Surgical types do not affect the incidence of awareness of patients under CPB。

Abstract：Background It is internationally accepted that in drug-nave individuals with hepatitis C virus (HCV) and human immunodeficiency virus (HIV) co-infection, chronic hepatitis C should be treated first if the CD4 cell count does not require the initiation of anti-retroviral therapy. Present paper evaluated the clinical effect and side-effect of interferon-α (IFN-α) and ribavirin (RBV) combination therapy for Chinese patients with HCV-HIV co-infection, and compared with them for HIV infection alone. Methods Ten patients with HCV-HIV and 17 patients with HCV received 5 million unit IFNα-2b every other day intramuscularly, and 300 mg RBV triple daily by oral. Dynamic observations were made for HCV RNA and HIV RNA loads, CD4+ and CD8+ T lymphocyte counts, liver function and blood cell measurement, and the medicine side-effects. Results After 12-week and 24-week treatments of IFN-α and RBV combination therapy, mean HCV RNA levels reduced 1.14 logs and 1.56 logs from the baseline at week 0 in HCV-HIV co-infection, and reduced 1.48 logs and 1.75 logs in HCV infection, respectively. The HIV RNA levels decreased 1.22 logs and 1.32 logs from the base line; however, there were no obvious different changes at T lymphocyte counts of HCV-HIV and HCV patients through 24-week treatments. Whole 27 patients showed satisfactory biochemical response to therapy. There were some mild or mediate influence-like symptoms, intestinal uncomfortable and depressed blood cell counts in early stage of the treatments. No neuropsychiatric and auto-immune disorders were found. Conclusions IFN-α and RBV combination therapy had similar anti-HCV effects during 24-week treatment for HCV-HIV and HCV infected Chinese patients, and some anti-HIV effect. There were no obvious different biochemical responses and side-effects between two groups above。

Abstract：Background Macrophage migration inhibitory factor (MIF) plays a pivotal role in inflammatory and immune-mediated diseases. However, its molecular function and role in gastrointestinal diseases has rarely been studied and thus warrants an in-depth investigation. This study was designed and conducted to determine MIF expression in Helicobacter pylori (H. pylori)-induced gastritis and the effect of H. pylori on MIF expression in monocytes in vitro. Methods Gastric specimens of 62 patients with chronic gastritis were obtained through endoscopic biopsies. Both gastric antrum and body were examined for histopathologic changes. Positive H. pylori was determined through rapid urease test and histopathological examination. A patient was classified as H. pylori positive if both tests showed positive results. The updated Sydney System was employed to assess the severity and activity of gastric inflammation. Double immunoassaying for MIF/T-cells (CD45RO) and MIF/macrophage (KP1), as well as in situ hybridization for the expression of MIF mRNA were used for the current analysis. THP-1, a monocyte cell line, was co-incubated with H. pylori strains (ATCC26695) and subsequently examined for the expression of MIF protein and mRNA by enzyme linked immunosorbent assay and retrospective transcription-polymerase chain reaction, respectively. Results Among 62 patients with chronic gastritis, significant increase in total T-cells, MIF+ T-cells, total macrophages, MIF+ macrophages and MIF mRNA+ cells was observed in 42 H. pylori positive patients compared to H. pylori negative patients. Moreover, the increase of the MIF mRNA+ cells was highly correlated with the severity of the disease(number of MIF mRNA+cells/mm2, mild: 2834±382, moderate: 3569±123, severe: 3881±118, P<0.01). In vitro results showed that the expression of MIF protein and mRNA in monocytes was significantly increased after incubation with H. pylori strains.Conclusions Overexpression of MIF is common in H. pylori-induced gastric inflammation, which suggests MIF may play an important role in the initiation and development of this disease.

Nonvalvular atrial fibrillation (NVAF) is the most common sustained cardiac arrhythmia in clinical practice, which if untreated results in a doubling of cardiovascular morbidity and mortality. AF is an independent predictor of stroke, with an annual risk 5 to 6 times higher than patients in sinus rhythm.1 During recent years, several randomised clinical trials conducted by investigators around the world involving 13 843 participants with NVAF have demonstrated convincingly the value of warfarin therapies for stroke prevention in high risk patients.2-8 However, the dose response of warfarin is complex and its activity is easily altered by concurrent medications, food interactions, alcohol and illnesses. Adherence to medical advice and routine monitoring of the international normalized ratio (INR) is important, because low anticoagulant intensity predisposes the patients to thromboembolic complications and high intensity to haemorrhage. Studies suggested that anticoagulant clinics could improve the quality of anticoagulation control,9 and anticoagulant clinics are common in western countries. However, in China, most AF patients taking warfarin usually attend the outpatient clinic of cardiology, while the quality of anticoagulation control is never investigated. We therefore assessed anticoagulation control in the outpatient clinic of cardiology, and the quality of anticoagulation control since the establishment of anticoagulant clinics。

Atrial fibrillation (AF) is a common tachyarrhythmia and may cause serious complications, such as stroke. When atrial pressure was elevated, the effect refraction period (ERP) was shortened and the conductivity in atria was slowed and the heterogeneity of different parts of atria was increased. These changes facilitate the occurrence and maintenance of AF. Recent researches demonstrated that pulmonary veins (PVs) are important sources of ectopic beats in the initiation of paroxysmal AF. In patients with drug-resistant chronic AF and structural heart disease, after electrical cardioversion, the PVs are also the dominant trigger in reinitiating AF.1 Yamane et al2 reported that, AF patients were often with dilated PVs if the AF was initiated by focal activity in PVs. Atrial myocardial fibers wrap around the PVs entering the left atrium to form PV myocardial sleeves (PVMSs), and this structure is the origin of focal activity. Little is known about the effects of elevated atrial pressure on PV electrophysiology. In the present study, we found that, spontaneous activity in PVMSs could be induced by elevated atrial pressure and it could affect the atrial rhythm。

Kai Xin San (KXS) is a category of traditional complex prescription that was first recorded in Bei Ji Qian Jin Yao Fang by SUN Si-miao in the Tang Dynasty and then also recorded in Tai Ping Hui Min He Ji Ju Fang, Qian Jin Yao Fang and Gu Jin Lu Yan in later generations. It was mainly used by herbalist doctors to treat symptoms including desolation, moodiness, forgetfulness etc., which are similar to the neurosis such as depression, anxiety and difficulty in studying and memory in the West medicine. The former recorded formulas were all composed of ginseng, polygala, hoelen and acori graminei with different proportion. But there are no systematic studies on the clinical adaptive symptom corresponding to different matching and the best anti-depressive matching so far。

With the increase of clinical use of cardiac pacemaker, a certain kinds of severe leads-related complications (especially infection) have presented in a few patients who underwent pacemaker implantation. The best way to manage this problem is to remove the transvenous leads.1,2 The technique for percutaneous removal of transvenous leads have undergone considerable development in western countries over the past 2 decades. However, there was scarce data on the application of this technique in China. This article reports the results of transvenous extraction of 171 permanent pacemaker leads with the standard lead extraction devices and intravascular countertraction technique during the period from January 1996 to May 2005 in the Center of Arrhythmia Diagnosis and Treatment, Fu Wai Hospital, Beijing, China。

Approximately 15%-20% of the patients undergoing percutaneous coronary intervention (PCI) procedure complicate with diabetes and this patient population continues to be a particular challenge for both the interventional cardiologist and the cardiac surgeon.1 It is well documented that diabetes is associated with more diffuse and severe coronary atherosclerosis. Long-term outcome after PCI is clearly worse in diabetics compared with non-diabetics.2 However, there is little information on the procedural and in-hospital outcomes of elective PCI in diabetic patients. In this study we analyzed the practice and in-hospital outcomes in a large series of consecutively treated patients with and without diabetes who underwent elective PCI。

Pulmonary vein (PV) stenosis or occlusion is a recently described complication of radiofrequency ablation for atrial fibrillation (AF), though favorable results of PV ostial ablation have fueled great enthusiasm.1,2 The presenting symptoms include dyspnea, cough, hemoptysis, pleural infusion and pulmonary consolidation.3

Atrial arrhythmia is common in clinic. Recently, it was revealed that ectopic impulses originating in sleeve muscles around the orifices of pulmonary veins (PVs) were deemed to be one of the most important reasons that trigger or drive atrial arrhythmia, which was called myocardial sleeve related arrhythmia. Electrical isolation by radiofrequency ablation is becoming highlight and proved to be an effective method for the arrhythmia. We report a 55-year-old man with paroxysmal atrial tachy-arrhythmias admitted for PV electrical isolation. An abscess was discovered in right inferior lung before the operation. The arrhythmia was disappeared after resection of the abscess. It implies that for such sufferer and recidivist after ablation, the factors outside the pulmonary veins should be excluded or treated as far as possible, especially before radiofrequency ablation therapy。

Pseudocoarctation, frequently called kinking or buckling of the aorta, is a rare condition, thought to be of a congenital origin and characterized by elongation and kinking of the aorta at the level of the ligamentum arteriosum, without a pressure gradient across the lesion. Misdiagnosis is often encountered and its treatment remained controversial. Herein we report a case of pseudocoarctation of the aorta associated with aneurysm formation。