Optimized Fluoroscopy Setting and Appropriate Project Position Can Reduce X-ray Radiation Doses Rates during Electrophysiology Procedures

Background:

Nonfluoroscopic three-dimensional electroanatomical system is widely used nowadays, but X-ray remains indispensable for complex electrophysiology procedures. This study aimed to evaluate the value of optimized parameter setting and different projection position to reduce X-ray radiation dose rates.

Methods:

From June 2013 to October 2013, 105 consecutive patients who underwent complex ablation were enrolled in the study. After the ablation, the radiation dose rates were measured by two different settings (default setting and optimized setting) with three projection positions (posteroanterior [PA] projection; left anterior oblique [LAO] 30° projection; and LAO 45° projection). The parameter of preset voltage, pulse width, critical voltage, peak voltage, noise reduction, edge enhancement, pulse rate, and dose per frame was modified in the optimized setting.

Results:

The optimized setting reduced radiation dose rates by 87.5% (1.7 Gy/min vs. 13.6 Gy/min, P < 0.001) in PA, 87.3% (2.5 Gy/min vs. 19.7 Gy/min, P < 0.001) in LAO 30°, 85.9% (3.1 Gy/min vs. 22.1 Gy/min, P < 0.001) in LAO 45°. Increase the angle of projection position will increase the radiation dose rate.

Conclusions:

We can reduce X-ray radiation dose rates by adjusting the parameter setting of X-ray system. Avoiding oblique projection of large angle is another way to reduce X-ray radiation dose rates.     

Resultados de la ablación con catéter con mínimo o nulo empleo de fluoroscopia en pacientes pediátricos con taquiarritmias supraventriculares

Introduction and objectivesIonizing radiation exposure in catheter ablation procedures carries health risks, especially in pediatric patients. Our aim was to compare the safety and efficacy of catheter ablation guided by a nonfluoroscopic intracardiac navigation system (NFINS) with those of an exclusively fluoroscopy-guided approach in pediatric patients.MethodsWe analyzed catheter ablation results in pediatric patients with high-risk accessory pathways or supraventricular tachycardia referred to our center during a 6-year period. We compared fluoroscopy-guided procedures (group A) with NFINS guided procedures (group B).ResultsWe analyzed 120 catheter ablation procedures in 110 pediatric patients (11 ± 3.2 years, 70% male); there were 62 procedures in group A and 58 in group B. We found no significant differences between the 2 groups in procedure success (95% group A vs 93.5% group B; P = .53), complications (1.7% vs 1.6%; P = .23), or recurrences (7.3% vs 6.9%; P = .61). However, fluoroscopy time (median 1.1 minutes vs 12 minutes; P < .0005) and ablation time (median 96.5 seconds vs 133.5 seconds; P = .03) were lower in group B. The presence of structural heart disease was independently associated with recurrence (P = .03).ConclusionsThe use of NFINS to guide catheter ablation procedures in pediatric patients reduces radiation exposure time. Its widespread use in pediatric ablations could decrease the risk of ionizing radiation.     

Is mitochondrial DNA copy number a good prognostic marker in resectable pancreatic cancer?

Background

The aim of this prospective study was to investigate mitochondrial DNA (mtDNA) copy number in a group of resectable pancreatic cancer (PC) tumor tissues and adjacent normal pancreatic tissues, and to explore the correlation between the mtDNA content in tissues and the clinicopathological parameters and the overall survival.

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%).     

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。     

Relationship of different surgical margins with recurrence-free survival in patients with hepatocellular carcinoma

To investigate the impact of different surgical margin and recurrence-free survival in patients with hepatocellular carcinoma (HCC). The data of 601 patients who underwent curative hepatectomy for HCC between January 1997 and December 2009 were analyzed. Milan group and exceeding Milan group were divided according to the Milan Criteria. Each of them was divided into 3 groups: group A (surgical margin ≤ 1 mm), group B (1 mm < surgical margin ≤ 9 mm) and group C (surgical margin ≥ 10 mm). The relationship between surgical margin and recurrence-free survival in different groups was analyzed. In Milan group recurrence-free survival of group C was more than group B and group B more than group A (P < 0.05). And in the exceeding Milan group recurrence-free surgical of group B was more than group A. There were no statistic differences within groups of B and C. Enlarging surgical margin may increase recurrence-free survival in HCC under Milan criteria.1mm in cases of exceeding Milan criteria may be regarded as the suitable surgical margin for operation of HCC.     

Catheter ablation of atrial fibrillation in the elderly

Background Atrial fibrillation （AF） catheter ablation has emerged as a promising treatment strategy for AF, but has not been widely adopted in the elderly population. The present study aimed to determine the safety and efficacy of AF catheter ablation in the elderly popula-tion. Methods and Results The study population consisted of 316 patients with paroxysmal AF who underwent left atrial ablation. Ninety-five patients were≥65 years （48 males, mean age 68.9 ± 3.0 years old） and 221 patients were〈65 years old （130 males, mean age 52.5 ± 10.4 years old）. After a mean follow-up period of 34.0 ± 15.1 months, 55 （57.9%） patients in the elderly group were free from ar-rhythmia recurrence compared with 149 （67.4%） patients in the younger group （P=0.169）. Procedural complications were uncommon in both study groups. In logistic regression analysis, left atrial diameter （P=0.003）, hypertension （P=0.001）, dyslipidemia （P=0.039）, and coronary artery disease （P=0.018） were independent predictors of AF recurrence in the elderly population. Conclusions Catheter ablation of AF is safe and effective in older patients. Invasive strategies should be considered as an alternative choice in symptomatic elderly patients with AF.     

心房颤动消融术中合并室上性心动过速的相关性研究

目的对心房颤动(房颤)消融术中合并阵发性室上性心动过速(室上速)的患者进行特征性分析。方法回顾性选取2016年1月至2018年6月浙江大学医学院附属邵逸夫医院庆春院区心内科所有接受房颤消融术的患者(1484例),依据术中是否合并室上速分为合并室上速组和未合并室上速组,分析性别、年龄、房颤类型是否与房颤消融术中合并室上速的关系。同时,以年龄50岁和65岁为界点,再次进行分层分析。术中合并室上速组患者明确机制后同时行慢径改良或旁路消融,进行长期随访。结果房颤消融术中合并室上速共41例(41/1484,2.76%)。其中,合并房室结折返性心动过速(AVNRT)29例,合并房室折返性心动过速(AVRT)12例。女性房颤组合并室上速(25/505)明显高于男性组(16/979,4.95%对1.63%,P<0.001);≤50岁房颤组合并室上速(8/133)的患者明显高于>50岁组(33/1351,6.02%对2.44%,P=0.016);阵发性房颤组合并室上速(29/741)的患者明显高于持续性房颤组(12/743,3.91%对62%,P=0.007)。Logistic回归分析显示女性、≤50岁、阵发性房颤是房颤消融术中合并室上速患者的高危因素(女性:OR=0.292,95%CI 0.151~0.565,P<0.050;≤50岁:OR=0.301,95%CI 0.131~0.689,P=0.004;阵发性房颤:OR=0.456,95%CI 0.230~0.906,P=0.025)。结论房颤消融术中患者应同时行电生理检查排除室上速,尤其是年龄较轻的女性阵发性房颤患者。