起源点邻近二尖瓣环的频发室性早搏体表心电图特征及射频消融治疗

目的评估起源点邻近二尖瓣环的频发室性早搏(简称室早)体表心电图特点及射频消融治疗效果。方法10例频发室早患者接受常规电生理检查及射频消融治疗,对所有病例12导联体表心电图进行分析。结果10例室早均消融成功,并证实起源点邻近二尖瓣环的不同部位,根据成功消融靶点将本组病例分为3组,二尖瓣环前侧壁组(4例)、二尖瓣环后侧壁组(3例)、二尖瓣环后间隔组(3例)。所有病例胸前导联R波移行区位于V1～V2导联,绝大部分病例V6导联可见s波。对各组二尖瓣环室早心电图做进一步比较,可概括出系列心电图判断指标用以估计消融靶点的部位。结论射频消融治疗起源点邻近二尖瓣环的频发室早可取得良好效果,掌握其体表心电图特点有助于判定室早的起源部位。     

Control of hospital acquired infections in the ICU: A?service perspective

Background

The service setting has some unique strengths and weaknesses that must be kept in mind when organizing Hospital acquired infections (HAI) prevention interventions.

Methods

Following an initial study to gather data regarding HAI in the Surgical intensive care unit (ICU) we put into place various infection control interventions. The present study was carried out to analyse the effect of these interventions on the incidence of HAI in the ICU.

Results

The total admissions to the ICU were 253 patients. Eighty eight patients (34.78%) were admitted for more than 48 hr, 165 patients stayed for less than 48 h. The frequency of HAI was 7.95% (95% CI 3.54, 15). Hospital acquired pneumonia was observed in 2 of the 88 patients (2.27%) (95% CI 0.38, 7.30) which amounted to 9.70 infections per 1000 ventilator days. Bloodstream infection was detected in 3 out of 88 patients (3.4%) (95% CI 0.87, 8.99) amounting to 6.54 fresh infections per 1000 Central Venous Catheter days. Urinary tract infection was observed in 2 (2.27%) (95% CI 0.38, 7.30) at 2.86 fresh infections per 1000 catheter days. As compared to the previous study we found that there was a decline of HAI ranging from 60 to 70%.

Conclusion

Our study demonstrated that by meticulously following infection control protocols especially tailored to the service setting the incidence of HAI''s can be reduced. However, the challenge is in maintaining the gains achieved since there is a rapid turnover of manpower in the ICU and a lack of a structured ICU design model.     

Entrapment of circular mapping catheter in the mitral valve

BACKGROUND: Ablation procedures in the left atrium for treatment of atrial fibrillation are becoming increasingly common. The procedure often involves placing one or two circular mapping catheters in the left atrium. Entrapment of an ablation catheter in the mitral valve during ablations of left-sided accessory pathways by the retrograde approach has been described in two earlier published reports. More recently, several reports describe similar entrapment of a mapping catheter. In a recently published review, however, only one case of unspecified valve damage was registered among 8745 atrial fibrillation procedures. OBJECTIVE: The purpose of this study was to evaluate patients with entrapment. METHODS: Retrospective analysis of electrophysiological results. RESULTS: We describe three patients with entrapment during ablations for atrial fibrillation. The entrapments occurred with three different operators at three different electrophysiological laboratories within 2 years. The complication described here may be more common than is widely appreciated. CONCLUSIONS: From our figures, we estimate the incidence of the complication to 0.9% (95% confidence interval, 0.2-2.5%).     

Atrial flutter ablation: efficacy and cost-effectiveness of a single decapolar electrode to demonstrate bidirectional isthmus block.

AIMS: To evaluate whether a single decapolar electrode is a reliable and cost-effective substitute for the 'Halo' catheter to map the circuit and detect bidirectional isthmus block during atrial flutter (AFL) ablation. METHODS AND RESULTS: Twenty-four patients underwent AFL ablation by using the decapolar electrode in the infero-lateral wall of right atrium (group A) while a 'Halo' catheter was used in 11 patients (group B). Both groups had similar clinical characteristics. Anti-clockwise rotation (20 patients), clockwise (3 patients) or both forms of AFL (1 patient) were detected in group A. All patients in group B had anti-clockwise AFL. Bidirectional isthmus block was completed in 22 patients of group A and in 9 of group B (P=NS) while incomplete isthmus block was detected in 2 patients in each group (P=NS). Mean fluoroscopy and procedure time was 27 +/- 47 min, 107 +/- 36 min in group A and 14 +/- 19 min, 114 +/- 65 min in group B (P=NS). AFL relapsed in 3 patients of group A (follow-up 7 +/- 4 months) and in 2 of group B (4 +/- 2 months). CONCLUSION: A single decapolar electrode is a reliable method to map the circuit and demonstrate bidirectional isthmus block during AFL ablation. The cost of the decapolar electrode is a quarter of that of the 'Halo' catheter. This represents a significant saving particularly for centres with a substantial number of AFL ablations.     

Identification of successful catheter ablation sites in patients with ventricular tachycardia based on electrogram characteristics during sinus rhythm

BACKGROUND: Zones of slow conduction facilitate reentry, the major mechanism of ventricular tachycardia (VT) after myocardial infarction (MI). Identification of these zones during sinus rhythm (SR) is desirable for radiofrequency (RF) catheter ablation of VT. Local conduction velocity may correlate with electrogram duration. OBJECTIVES: The purpose of this study was to revise the definition of normal electrogram characteristics and to reevaluate the significance of low-amplitude, long-duration electrograms recorded during SR to select RF catheter ablation sites in patients with VT. METHODS: Electroanatomic mapping was performed during SR in 10 control patients with normal left ventricles (LVs) and in 10 patients with stable VT after MI. From the controls, reference values for electrogram amplitude, duration (first peak to last peak distance), and fragmentation (positive deflection) were derived. In patients after MI, areas with signals exceeding these values were annotated and related to successful ablation sites. RESULTS: Ninety-five percent of normal LV electrograms were > or =1.0 mV and < or =28 ms (range 5-39 ms) and all had < or =4 deflections. Based on these results, cutoff values were set at 1 mV, four deflections, and 40 ms. In infarcted hearts, 653 electrograms (44%) were <1.0 mV and of these, 303 were > or =40 ms with >4 deflections and restricted to circumscribed areas. Twenty-seven of 28 targeted VTs remained noninducible after RF catheter ablation within these areas, resulting in 86% sensitivity and 94% specificity for low-amplitude, long-duration electrograms predicting successful ablation sites. CONCLUSION: Identification of successful RF target areas during SR in patients with VT is feasible with high sensitivity and specificity using a mapping strategy based on voltage and duration criteria.     

典型心房扑动射频消融术后发生心房颤动患者的心房电生理特性

分析典型心房扑动(简称房扑)射频消融术后发生心房颤动(简称房颤)患者的心房电生理特性,探讨心房内传导时间在房颤发生中的意义。56例典型房扑患者,其中19例有器质性心脏病,16例在消融前有房颤发作。所有患者均进行常规的电生理检查及标测,记录消融前后心房的电生理参数。根据消融术后随访是否有房颤的发生分为两组进行分析。结果:56例房扑患者全部消融成功,随访14±12(6～60)个月,中位数14个月。消融术后15例有房颤发作,其中3例进展为慢性房颤。15例有房颤发作患者的年龄较无房颤发作的患者大(57.1±13.6岁vs42.3±11.2岁,P<0.05),消融术前和术后的高右房至冠状窦的传导时间延长(分别为98.4±17.1msvs67.8±16.5ms;93.1±18.4msvs70.2±19.7ms;P均<0.05)。多因素Cox回归分析消融前有房颤发作的病史(危险比2.3,95%CI1.425～4.632,P=0.02)和窦性心律下高右房至冠状窦的传导时间超过90ms(危险比1.7,95%CI1.215～3.758,P=0.03)是预测射频消融术后发生房颤的独立的危险因素。结论:典型房扑射频消融术后发生房颤患者心房内传导延迟,并且房内传导延迟是预测射频消融术后发生房颤的重要电生理指标。     

The effect of different treatment strategies on left atrial size in patients with lone paroxysmal atrial fibrillation—a prospective cohort study

INTRODUCTION: The effect of different treatment strategies of atrial fibrillation on left atrial (LA) size has not been compared in lone paroxysmal atrial fibrillation. The objective of the present study was to evaluate the evolution of LA size over time in patients who underwent different treatment interventions. METHODS AND RESULTS: Two hundred forty patients with lone paroxysmal atrial fibrillation were assigned to four groups. The circumferential pulmonary vein ablation (CPVA) group (n = 60) was treated with CPVA, segmental pulmonary vein isolation (SPVI) group (n = 60) with SPVI, AMIO group (n = 60) with amiodarone alone, and AMIO + LO group (n = 60) with amiodarone plus losartan. LA diameter was measured with transthoracic echocardiogram at baseline, 3, 6, 9, and 12 months after the interventions. In the CPVA group, LA size at third, sixth, ninth, and 12th month had a significant decrease than that at baseline and in the other three groups. LA size in patients with atrial fibrillation recurrence in the four groups was significant higher than that in patients with no atrial fibrillation recurrence (P = 0.002-0.001). CONCLUSION: The results suggested that a shortened LA size is not consistent with improved sinus rhythm maintenance. Although maintenance of sinus rhythm is not the only factor in determining shrinking or enlargement of the left atrium, inhibiting or eliminating activity of the pulmonary vein is very important for paroxysmal atrial fibrillation. Atrial fibrillation recurrence is a main factor contributing to enlargement of the LA.     

TACE联合PRFA治疗原发性肝癌有效性和安全性的meta分析

目的对原发性肝癌肝动脉化疗栓塞(transarterial chemoembolization,TACE)联合经皮射频消融(percutaneous radiofrequency ablation,PRFA)治疗的有效性和安全性进行评价。方法通过计算机检索中国知网、中国生物医学文献数据库、维普期刊数据库、Pub Med、Cochrane图书馆、EMbase数据库中关于TACE联合PRFA治疗原发性肝癌的效果及安全性的研究,对文献质量进行严格评价和资料提取,对符合质量标准的研究文献进行meta分析。结果本研究共纳入10篇文献累计病例798例。结果显示,TACE联合PRFA组治疗后3年总体生存率、肿瘤灭活率及肿瘤复发率均优于TACE组[OR=2.72,95%CI(1.81,4.10),P0.01;OR=3.74,95%CI(2.25,6.23),P0.01;OR=0.38,95%CI(0.24,0.61),P0.01],而在肝脏甲胎蛋白转阴率方面两组相比差异无统计学意义[OR=1.40,95%CI(0.65,3.01),P=0.39]。纳入文献相关并发症发生较少。结论 TACE联合PRFA治疗原发性肝癌的有效性和安全性显著优于TACE单独疗法,然而还需加大研究文献量及样本量,以增加论证强度。     

超声引导下射频消融术联合靶向治疗对晚期肝癌患者生命质量的影响

目的探讨超声引导下射频消融术(radiofrequency ablation,RFA)联合靶向治疗对晚期肝癌患者生命质量的影响。方法将90例诊断为晚期肝癌的患者随机分为对照组与观察组,每组45例。两组均予吉非替尼联合卡培他滨靶向治疗,观察组在靶向治疗的基础上行超声引导经皮腹腔穿刺RFA,治疗前及治疗后4周采用肿瘤生命质量核心量表(core quality of life questionnaire,QLQ-c30)进行评估并比较。结果治疗后两组QLQ-c30整体功能、特异性症状模块各条目评分均明显优于治疗前,观察组上述指标均优于对照组,差异有统计学意义(P0.05)。结论超声引导下RFA联合靶向治疗较单纯靶向治疗能更好地改善晚期肝癌患者的生命质量。     

肾交感神经消融治疗高血压及其研究进展

肾交感神经的过度激活可能是高血压的产生和维持的关键因素,肾交感神经消融属选择性的去交感神经化治疗,为高血压的治疗提供了新途径,本文对肾交感神经消融治疗高血压的安全性、有效性及其适应症的进一步拓展作一综述。