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81.
目的通过比较右室间隔部起搏和右室心尖部起搏电极参数和心功能的变化趋势,选择更为有利的起搏方式。方法选取心尖部起搏21例和间隔部起搏21例,术时、12个月、24个月随诊,分别作心脏彩色多普勒超声检查,记录左室舒张末期内径(LVEDD)、左室射血分数(LVEF)、起搏心电图测量Ⅱ导联QRS波时限、抽血查氨基末端脑钠肽前体(NT-proBNP)、起搏器程控仪记录阈值、阻抗、R波感知进行比较。结果间隔部组比心尖部组QRS时限和电极阻抗小,随起搏时间延长QRS时限、NT-proBNP、LVEDD增加、LVEF(%)下降,心尖部组表现较为明显。结论间隔部起搏QRS波较窄,LVEF(%)下降缓慢、LVEDD(mm)和NT-proBNP(pg/m1)升高缓慢,与心尖部起搏比较,心室同步性好、可延缓心功能减退,是右室起搏较好的选择部位。 相似文献
82.
CHARLES A. HENRIKSON M.D. KARL ZHANG B.S. JEFFREY A. BRINKER M.D. 《Pacing and clinical electrophysiology : PACE》2010,33(6):721-726
Background: Endovascular lead extraction is an important component of the management of patients with chronically implanted arrhythmia control devices. Although it is associated with the potential for significant morbidity and mortality, there is little information about its scope and practice. Methods: We surveyed 1,000 physician members of the Heart Rhythm Society via e‐mail solicitation. Results: Of the 252 respondents (25%), 221 (88%) reported either performing extractions themselves (63%), or having privileges at a hospital where extractions are performed (25%). Electrophysiologists perform extractions at most sites (83%) but cardiac surgeons perform endovascular lead extraction at a significant minority of sites (20%). Most respondents report low annual volumes of extractions at their site: 15% reported <10 procedures/year, 42% 10–25 procedures/year, 23% 26–50 procedure/year, and only 19% reported >50 procedures/year. Thirty‐six percent of respondents reported that extractions were done in the operating room (OR) with surgeon present or immediately available, 39% in the electrophysiology (EP) lab with surgeon and OR identified and available, and 25% in EP lab without a surgeon or OR identified. The overall risks of lead extraction were felt to be 1–5% of major complication and 0.5–1% of mortality, roughly in line with published data. Conclusions: While there is agreement as to the risk of major complication and death from lead extraction, the degree of surgical availability varies considerably. The new guidelines document recommends the ability to promptly initiate an emergent surgical procedure, and this should be an important goal for all extractionists. (PACE 2010; 33:721–726) 相似文献
83.
HOONG SERN LIM M.D. MAURO LENCIONI M.D. HOWARD MARSHALL M.D. 《Pacing and clinical electrophysiology : PACE》2010,33(5):549-552
Background : Antitachycardia pacing (ATP) is an effective treatment of ventricular tachycardia (VT). However, persistent failure of ATP in some patients is well recognized. Methods : A method of deriving the local activation time from stored intracardiac electrograms in implantable cardioverter defibrillators is described. Using a case‐control design, the local activation times were compared between patients with persistent unsuccessful ATP with comparable controls with successful ATP. Results : The local activation times during VT in patients with failed ATP were longer at 120–180 ms compared with corresponding control patients with successful ATP (60–80 ms). The local activation time expressed as a proportion of VT cycle length in patients with failed ATP compared with patients with successful ATP were 0.40 ± 0.08 versus 0.19 ± 0.08 (P = 0.012). Conclusion : A novel method of deriving local activation time is described, and delayed local activation time may explain failure of ATP in terminating VT in some patients. (PACE 2010; 549–552) 相似文献
84.
GREGORY WOO M.D. THOMAS BURKART M.D. WILLIAM MILES M.D. SHERRY SAXONHOUSE M.D. JAMIE CONTI M.D. 《Pacing and clinical electrophysiology : PACE》2010,33(2):246-247
An asymptomatic patient with a Teletronics Accufix atrial lead (Teletronics, Englewood, CO, USA) presented for an annual fluoroscopic examination. The examination revealed a retention wire fracture, which occurred 18 years after the initial implantation. Annual fluoroscopic examination of these leads should still be performed. (PACE 2010; 33:246–247) 相似文献
85.
Wolfgang Schoels MD David Steinhaus MD W. Ben Johnson MD Gilles OHara MD Joerg O. Schwab MD Inge Jenniskens MSc Paul J. DeGroot MS Feng Tang PhD Erhard Helmling MD EnTrust Clinical Study Investigators 《Heart rhythm》2007,4(7):879-885
BACKGROUND: Previous studies in implantable cardioverter-defibrillator (ICD) patients demonstrated the efficacy and safety of antitachycardia pacing (ATP) for rapid ventricular tachycardias (VT). To prevent shock delay in case of ATP failure, a new feature (ATP during charging) was developed to deliver ATP for rapid VT while charging for shock. OBJECTIVE: The purpose of this study was to determine the efficacy and safety of this new feature. METHODS: In a prospective, nonrandomized trial, patients with standard ICD indication received an EnTrust ICD. VT and ventricular fibrillation (VF) episodes were reviewed for appropriate detection, ATP success, rhythm acceleration, and related symptoms. RESULTS: In 421 implanted patients, 116 VF episodes occurred in 37 patients. Eighty-four (72%) episodes received ATP during or before charging. ATP prevented a shock in 58 (69%) of 84 episodes in 15 patients. ATP stopped significantly more monomorphic (77%) than polymorphic VTs (44%, P = .05). Five (6%) episodes accelerated after ATP but were terminated by the backup shock(s). No symptoms were related to ATP during charging. In four patients, 38 charges were saved by delivering ATP before charging. Of 98 induced VF episodes, 28% were successfully terminated by ATP versus 69% for spontaneous episodes (P <.01). CONCLUSION: Most VTs detected in the VF zone can be painlessly terminated by ATP delivered during charging, with a low risk of acceleration or symptoms. ATP before charging allows delivery of two ATP attempts before shock in the same time that would otherwise be required to deliver only one ATP plus a shock. It also offers potential battery energy savings. 相似文献
86.
体外无创性临时心脏起搏的临床应用 总被引:2,自引:0,他引:2
目的 评价体外无创性临时心脏起搏 ( ENCP)对心脏骤停及急性严重缓慢性心律失常的抢救效果、安全性。方法 19例心脏骤停患者和 18例有严重临床症状缓慢性心律失常患者紧急行 ENCP。结果 所有病人均在 1~ 5 min内在床边得到 ENCP。心脏骤停组 12例起搏成功 ,其中 5例复苏 ,起搏成功者平均起搏阈值 ( 10 5 .2± 15 .6) m A,起搏成功率 63 .1% ,起搏成功并复苏2 6.3 %。严重缓慢性心律失常组 17例 ENCP后临床症状迅速明显改善 ,平均起搏阈值 ( 75 .3± 2 1.5 ) m A,起搏成功率 94.4%。严重缓慢性心律失常组的起搏成功率明显高于心脏骤停组 ,起搏阈值明显低于心脏骤停组。所有患者起搏过程中均出现与起搏脉冲同步的胸部肌肉抽动 ,但只有 1例因胸痛在 ENCP维持下安装了经静脉临时心脏起搏器 ,其余病人虽有不适 ,均能接受 ENCP。所有 ENCP患者均未发现皮肤、软组织损伤及严重心律失常等不良反应。结论 体外起搏是心脏骤停、急性严重缓慢性心律失常行之有效的治疗手段。 相似文献
87.
88.
Gardiwal Ajmal; Yu Hong; Oswald Hanno; Luesebrink Ulrich; Ludwig Andreas; Pichlmaier Andreas Maximilian; Drexler Helmut; Klein Gunnar 《Europace : European pacing, arrhythmias, and cardiac electrophysiology》2008,10(3):358-363
Aims: There is increasing evidence that right ventricular (RV) pacingmay have detrimental effects by increasing morbidity and mortalityfor heart failure in implantable cardioverter–defibrillator(ICD) patients. In this study we prospectively tested the hypothesisthat cumulative RV pacing increases ventricular tachycardia/ventricularfibrillation (VT/VF) occurrence (primary endpoint) and hospitalizationand mortality for heart failure (secondary endpoint) in a predominantlysecondary prophylactic ICD patient population. Methods and results: Two hundred and fifty patients were divided into two groupsaccording to the median of cumulative RV pacing (2 vs. >2%)and prospectively followed-up for occurrence of primary andsecondary endpoints for 18 ± 4 months. Established predictorsfor VT/VF occurrence and heart failure events such as age, leftventricular ejection fraction (EF), QRS duration, history ofatrial fibrillation, and NT-proBNP were collected at enrolment.Multivariate Cox regression analysis revealed that cumulativeRV pacing > 2% and EF < 40% were independent predictorsfor VT/VF occurrence and heart failure events. Kaplan–Meieranalysis showed that patients with >2% cumulative RV pacingmore frequently suffered from VT/VF occurrence and heart failurehospitalization. Conclusion: Cumulative RV pacing > 2% and EF < 40% are independentpredictors for VT/VF occurrence and mortality and hospitalizationfor heart failure in predominantly secondary prophylactic ICDpatients. Our data show that algorithms capable of reducingcumulative RV pacing should be used more frequently in clinicalpractice. 相似文献
89.
90.
A Randomized Comparison of Alternative Techniques to Achieve Coronary Sinus Cannulation During Biventricular Implantation Procedures 总被引:1,自引:0,他引:1
Giuseppe De Martino Tommaso Sanna Antonio Dello Russo Gemma Pelargonio Loredana Messano Carolina Ierardi Daniele Gabrielli Quintino Parisi Paolo Zecchi Fulvio Bellocci Filippo Crea 《Journal of interventional cardiac electrophysiology》2004,10(3):227-230
INTRODUCTION: Biventricular pacing system implantation is a time-consuming and challenging procedure. A critical step in biventricular pacemaker implantation is coronary sinus (CS) cannulation. CS cannulation can be achieved either using dedicated guiding catheters (guiding catheter alone positioning strategy, GCA) or with the aid of an electrophysiology catheter advanced inside the guiding catheter (electrophysiology catheter aided positioning strategy, EPA). AIM OF THE STUDY: To evaluate whether the EPA technique is useful for reducing CS cannulation time compared to a conventional GCA technique. METHODS: Thirty-four consecutive patients were randomly assigned to the GCA (18 patients) or EPA (16 patients) CS cannulation strategy. RESULTS: Time to successful catheterization of CS was 5.0 +/- 2.4 min in the EPA group versus 10.1 +/- 5.4 min in the GCA group p = 0.004. Fluoroscopy time was 4.6 +/- 2.3 min in the EPA group versus 9.2 +/- 4.9 min in the GCA group p = 0.004. Total contrast dye volume to search and engage the CS ostium was 0.0 ml in the EPA group versus 14.3 +/- 3.4 ml in the GCA group p < 0.001. CONCLUSIONS: Cannulation of CS with the adjunct of an electrophysiology catheter to dedicated delivery systems significantly reduces procedural time, fluoroscopy time and contrast dye volume compared to a conventional strategy. 相似文献