Balloon-occluded retrograde transvenous obliteration for treatment of gastric varices

Rupture of gastric varices(GVs) can be fatal. Balloon-occluded retrograde transvenous obliteration(BRTO), as known as retrograde sclerotherapy, has been widely adopted for treatment of GVs because of its effectiveness, ability to cure, and utility in emergency and prophylactic treatment. Simplifying the route of blood flow from GVs to the gastrorenal shunt is important for the successful BRTO. This review outlines BRTO indications and contraindications, describes basic BRTO procedures and modifications, compares BRTO with other GVs treatments, and discusses various combination therapies. Combined BRTO and partial splenic embolization may prevent exacerbation of esophageal varices and shows promise as a treatment option.     

床边插管法在临时心脏起搏的应用

目的 :探讨在起搏脉冲发生器起搏与感知的指导下 ,结合心脏听诊定位进行临时心脏起搏的可行性。方法 :应用深静脉穿刺和带漂浮球囊的起搏电极 ,在起搏脉冲发生器起搏与感知的指导下结合心脏听诊定位 ,进行床旁临时心脏起搏。结果 :72例起搏均获成功 ,且均无严重心律失常发生。结论 :床旁临时心脏起搏无X光显示盲目插管法在起搏脉冲发生器起搏与感知的指导下结合心脏听诊定位是安全有效的     

Transvenous atrial defibrillation--techniques and clinical applications.

Atrial fibrillation (AF) is the most common arrhythmia requiring treatment. The most desirable therapy may be restoration and maintenance of sinus rhythm. Limitations of the current methods for cardioversion of AF have prompted the development of transvenous atrial defibrillation (TADF) as an alternative and more effective technique for converting AF. Recent advances in the technique of TADF, particularly in the design and configuration of the electrodes, and the use of an optimal biphasic shock waveform have dramatically improved the efficacy of TADF for the termination of all types of AF. The reduction in voltage and energy requirements for cardioversion by TADF may allow the procedure to be performed with little or no sedation and the risk of general anesthesia may be avoided. Both experimental and clinical studies have demonstrated the feasibility, safety, and efficacy of using TADF as a new temporary or "permanent" mode of electrical therapy for AF. It has several potential applications, from acute termination of AF in the electrophysiology laboratory and in patients who have failed to respond to external cardioversion, to its use as an implantable device for treating recurrent AF. This article reviews the current technique and clinical applications of TADF for treatment of AF.     

Transatrial selective coronary arteriography in pulmonary atresia with intact ventricular septum

We describe a technique for transvenous, transatrial selective coronary arteriography, which may prove useful in the diagnostic evaluation of the neonate with pulmonary atresia with intact ventricular septum when right ventriculography and antegrade aortography inadequately define the coronary arterial circulation. Cathet. Cardiovasc. Diagn. 43:174–176, 1998. © 1998 Wiley-Liss, Inc.     

Emergency transvenous ablation of atrioventricular conduction to control refractory atrial tachycardia

Three patients were referred for urgent investigation and treatmentof refractory arrhythmias. Each patient had failed to respondto antiarrhythmic drugs and in two patients direct current cardioversionwas also unsuccessful. Transvenous ablation of atrioventricularconduction was therefore thought appropriate. With a temporaryventricular pacing system in situ, a second electrode was usedto record His and atrial electro-grams. A 270 watt-second shockwas delivered through this lead when the His potential was maximized.The tachycardia was controlled in two patients and the procedurewas without deleterious effects.     

Temporal Stability of Defibrillation Thresholds with an Active Pectoral Lead System

Stability of Defibrillation Thresholds. Introduction : Monophasic defibrillation thresholds rise over time with a variety of lead systems. These chronic changes are attenuated or eliminated by biphasic waveforms, although the effect appears dependent upon the lead system. With the downsizing of pulse generator size to allow for routine pectoral implantation, active can lead systems have now become standard. However, the temporal stability of such lead systems has not been evaluated previously.
Methods and Results : This study was a prospective assessment of the changes of active pectoral defibrillation thresholds over time. Thresholds were measured at implant, predischarge, and at a mean follow-up of 50 days in 46 patients with a uniform testing protocol and shock polarity. The lead system was a dual-coil Endotak DSP lead with an active pectoral pulse generator. Defibrillation thresholds were 9.9 ± 5.5 J at implantation, 8.5 ± 6.0 J predischarge, and 7.6 ± 5.5 J at follow-up (ANOVA, P = 0.007). Moreover, only two patients developed an increased threshold > 5 J, and no patient had an inadequate safety margin at follow-up.
Conclusion : These results indicate that active pectoral defibirillation thresholds are stable over the first 2 months postimplantation and question the need for routine serial defibrillation threshold testing.     

A new atrial transseptal pacing electrode

Summary: The atrial septum provides a convenient structure to which a transvenous electrode can be attached securely. The Brockenbrough cardiac catheterization technique has been used to gain access to the left atrium. A new electrode has been fabricated which can be inserted into the left atrium through the lumen of a Brockenbrough catheter. The electrode is composed of a stainless steel coil attached inside the proximal end of a platinum cylinder at the cardiac terminal. Three Elgiloy wires, having a wing configuration, are attached inside the distal end of the platinum cylinder. The coil and cylinder are insulated by silicone rubber and the metallic surface area of the distal electrode tip equals 5 mm². This electrode has been implanted without difficulty or complications in five patients with tachycardia-bradycardia syndrome.     

Effect of Electrode Length on Atrial Defibrillation Thresholds

Electrode Length for Atrial Defibrillation. Introduction: Catheter-based electrodes have been used previously to terminate episodes of atrial fibrillation in animals and man. Typically, these electrodes span 6 to 7 cm, and lowest energy requirements are achieved when these electrodes are positioned in the distal coronary sinus and in the right atrium. The purpose of this study was to evaluate the use of longer electrode lengths for atrial defibrillation. Methods and Results: In 15 patients, two decapolar catheters were inserted, one into the distal coronary sinus and one in the right atrium. To provide longer electrodes lengths, a third catheter was inserted and alternated positioned in the right atrium or coronary sinus. A 6-cm electrode span was obtained by using the distal 8 rings on the coronary sinus catheter or 8 consecutive electrodes on the right atrial catheter and increased from 6 to 11 cm by connecting consecutive, nonoverlapping rings of the third catheter with the 10 rings of the initial right atrial or coronary sinus catheter. Atrial defibrillation thresholds were determined twice, in a randomized order, in each patient for each of the three combinations of electrode lengths. All 15 patients could he successfully converted to sinus rhythm without complications; however, one patient could be converted reproducibly with only 2 of the 3 electrode combinations. Mean thresholds were 306 ± 102 V, 5.9 ± 4.0 J for the 6 cm/6 cm electrode length combination with an impedance of 72 ± 18 ω. For the electrode combination using the 11-cm electrode in the right atrium, the defibrillation threshold was 296 ± 107 V, 5.8 ± 3.9 J with an impedance of 61 ± 17 ω and was 294 ± 91 V, 5.6 ± 3.6 J with an impedance of 55 ± 11 ω for the 11-cm electrode in the coronary sinus. There were no significant differences in defibrillation voltage or energy (P > 0.05) associated with the longer electrode lengths; however, the longer electrode lengths did significantly lower shock impedance (P < 0.05). Conclusion: The use of longer electrodes, when using the right atrium to coronary sinus shock vector, does not lower the defibrillation requirements for restoration of sinus rhythm.     

How to Implant a Leadless Pacemaker With a Tine‐Based Fixation

Two major studies have shown that leadless pacemakers are safe and effective for patients requiring right ventricular rate responsive pacing therapy. This positive result recently led to FDA approval of one of the available leadless pacing devices. While this new technology is promising, it requires a different skill set for safe implantation. In this article, we review in detail the different steps required for implantation of tine‐based leadless pacemakers while providing tips and tricks to minimize complications.     

经皮球囊二尖瓣成形术患者血浆心钠素和血管加压素水平的改变

选择１６例风湿性二尖瓣狭窄患者进行经皮球囊二尖瓣成形术。术后心功能改善Ⅰ～Ⅱ级。术前，左右心房血浆心钠素水平明显高于外周静脉。研究发现，心房心钠素分泌增加可分为两型：右房分泌为主型者（ｎ＝５）；左房分泌为主型者（ｎ＝１１）。前一型的左心房平均压和右心房平均压均明显高于后一型。两型的外周血浆心钠素水平均无显著差异。术后５ｍｉｎ、２０ｍｉｎ、１ｈ、２４ｈ等时点，左右心腔和外周血浆心钠素水平均较术前显著下降。１６例患者术后２０ｍｉｎ时的左心腔血浆心钠素水平的降低幅度与二尖瓣跨瓣压差降低幅度显著相关（ｒ＝０．５０２，Ｐ＜０．０５）。术后血管加压素水平也显著下降，术后２４ｈ下降达７７．９±２．９％。这提示，成功地经皮球囊二尖瓣成形术可使风湿性心脏病患者血浆心钠素和血管加压素水平显著下降。     

Unsuccessful deflation of a bifoil balloon during percutaneous mitral valvuloplasty

A middle-aged woman was subjected to balloon mitral valvuloplasty using a bifoil balloon catheter. After inflation the balloon failed to deflate inspite of negative suction, probably due to a kink. The balloon was perforated with a transseptal puncture needle in order to deflate it and save open heart surgery. © 1996 Wiley-Liss, Inc.     

Transvenous coronary angiography in dogs using synchrotron radiation

Summary The application of coronary angiography is limited because it requires arterial invasion and the direct injection of contrast agent into the coronary arteries. A prototype system has been developed which achieves sufficient sensitivity to the iodinated contrast agent to allow the visualization of coronary arteries in dogs after its intravenous injection. The system uses two fan beams of x-rays from an electron storage ring and a 300 element linear silicon detector. Two interlaced images, spaced at 150 eV above and below the K absorption edge of iodine (33.2 keV), are acquired and the logarithmic subtraction of these two images produces an image which has maximal sensitivity to iodine and minimal sensitivity to soft tissue and bone. This approach appears suitable for studies on human subjects.     

Transvenous ICD implantation after artificial tricuspid valve replacement. A new approach placing a transvenous ICD lead in the mid cardiac vein of the coronary sinus

Summary Implantation of a transvenous device in patients with a tricuspid valve replacement or a complex congenital heart disease with no access to the right ventricle represents problems. The lack of access to the right ventricle might preclude transvenous placement of a defibrillation lead at ICD implantation. A young patient (21 years) with a history of severe chest trauma with rupture of the tricuspid valve as well as the right coronary artery and consecutive inferior myocardial infarction was initially treated with tricuspid valve replacement (St Jude Medical artificial prosthesis, 33 mm) and a bypass graft to the right coronary artery. Four years later, the patient was admitted with a hemodynamically not tolerated ventricular tachycardia (VT: CL 250 ms, LBBB, left axis). The VT could be reproduced during electrophysiological testing. An ICD was implanted subpectorally in combination with a transvenous active fixation ICD lead. The transvenous ICD lead was placed via a guiding catheter into a coronary sinus branch (middle cardiac vein). Acceptable pacing and sensing values could be obtained. The defibrillation threshold was 25 J. In conclusion transvenous ICD lead implantation into a side branch of the coronary sinus in combination with a pectorally implanted “active can” ICD device seems to be an alternative approach. This approach may avoid implantation of additional subcutaneous defibrillation leads or even thoracotomy for ICD implantation.     

Percutaneous transvenous mitral commissurotomy for restenosis after surgical mitral valvotomy

Percutaneous transvenous mitral commissurotomy (PTMC) was performed in 350 patients. Of these patients, 51 (15%) (30 women and 21 men, aged 32 ± 11 years) had restenosis 11 ± 4 years following surgical valvotomy. Forty (79%) patients were in New York Heart Association (NYHA) class III and 11 (21 %) were in class IV. PTMC resulted in an increase in mitral valve area from 0.82 ± 0.3 to 1.9 ± 0.2 cm² (p < 0.001), an increase in cardiac index from 1.9 ± 0.4 to 2.8 ± 0.51/min/m² (p < 0.001), and a decrease in mean transmitral gradients from 29 ± 4 to 6 ± 4 mmHg (p < 0.001). The results did not differ from those observed in 299 patients without prior surgical valvotomy. On univariate analysis, the subvalvular fibrosis, assessed angiographically, and the duration from prior surgery were not found to influence the overall outcome. At 24 weeks, 46 of 48 (96%) patients in whom clinical follow-up was available, were found to be in NYHA class I and 2 (4%) patients were in class II. Thus, PTMC is a safe and effective procedure for patients with mitral restenosis following surgical valvotomy.     

Leadless versus transvenous single-chamber ventricular pacemakers: 3 year follow-up of the Micra CED study

Introduction

The Micra Coverage with Evidence Development (CED) Study is a novel comparative analysis of Micra (leadless VVI) and transvenous single-chamber ventricular pacemakers (transvenous VVI) using administrative claims data. To compare chronic complications, device reinterventions, heart failure hospitalizations, and all-cause mortality after 3 years of follow-up.

Methods

US Medicare claims data linked to manufacturer device registration information were used to identify Medicare beneficiaries with a de novo implant of either a Micra VR leadless VVI or transvenous VVI pacemaker from March 9, 2017 to December 31, 2018. Unadjusted and propensity score overlap-weight adjusted Fine-Gray competing risk models were used to compare outcomes at 3 years.

Results

Leadless VVI patients (N = 6219) had a 32% lower rate of chronic complications and a 41% lower rate of reintervention compared with transvenous VVI patients (N = 10 212) (chronic complication hazard ratio [HR] 0.68; 95% confidence interval [CI], 0.59−0.78; reintervention HR 0.59; 95% CI 0.44−0.78). Infections rates were significantly lower among patients with a leadless VVI (<0.2% vs. 0.7%, p < .0001). Patients with a leadless VVI also had slightly lower rates of heart failure hospitalization (HR 0.90; 95% CI 0.84−0.97). There was no difference in the adjusted 3-year all-cause mortality rate (HR 0.97; 95% CI, 0.92−1.03).

Conclusion

This nationwide comparative evaluation of leadless VVI versus transvenous VVI de novo pacemaker implants demonstrated that the leadless group had significantly fewer complications, reinterventions, heart failure hospitalizations, and infections than the transvenous group at 3 years, confirming that the previously reported shorter-term advantages associated with leadless pacing persist and continue to accrue in the medium-to-long-term.     

A Comparison of Pectoral and Abdominal Transvenous Defibrillator Implantation: Analysis of Costs and Outcomes

Traditionally cardioverter-defibrillator implantation was performed by surgeons under general anesthesia. However, with advances in lead and pulse generator technology, the surgical implantation technique has been simplified and routine pectoral pulse generator placement without general anesthesia is now possible. To assess the economic benefit of pectoral implantation, we analyzed 43 consecutive initial transvenous defibrillator implantations. The patients were grouped according to whether the implant was abdominal by a surgeon in the operating room (n = 23) or pectoral by an electrophysiologist in a laboratory (n = 20). The duration of hospitalization was significantly longer in the operating room than in the laboratory group (8.1 ± 3.4 vs 5.8 ± 2.4 days, p = 0.01), which was due primarily to the postoperative stay which averaged 1.9 days longer. Total costs were $40,274 ± 6,861 for the operating room cohort and $32,546 ± 3,634 for the lab group (p < 0.001). This reduction was due to a 32% lowering of professional costs and an 18% lowering of facility costs. We conclude that pectoral defibrillator implantation is cost effective and results in significant reductions of hospital stay.     

Patient profile and results of percutaneous transvenous mitral commissurotomy in mitral restenosis following prior percutaneous transvenous mitral commissurotomy vs surgical commissurotomy

Background

Patients with mitral restenosis who have undergone prior PTMC or surgical commissurotomy have increased. Predictors of outcome of repeat PTMC in either subgroup of patients may be different.

Aims and objectives

Aim was to assess and compare the immediate results of PTMC in patients who had undergone a prior PTMC or surgical commissurotomy.

Methods and results

This is a single center, prospective, open label study. Of 70 patients in study, 44 (62.85%) patients had prior history of PTMC and 26 (37.15%) had prior surgical commissurotomy (closed/open). Average time from the initial procedure was 8.88 ± 5.36 years overall, 6.75 ± 3.38 for patients with prior PTMC and 16.73 ± 3.67 for patients with prior surgical commissurotomy. Prior PTMC group had 75% female, patients with prior surgical commissurotomy were older (44 ± 7 vs 33.57 ± 9.1 years, p = 0.001), had higher NYHA class (III/IV in100% vs 86.36%, p = 0.006.), higher atrial fibrillation (73.1% vs 25% p < 0.0001) and higher Wilkins'' score (>8 in 88.46% vs 68.18%, p = 0.05). Successful PTMC was lower (65.4% vs 84.1%) in patients with prior surgical commissurotomy, though statistically not significant (p = 0.07). After PTMC, mitral valve area, PA systolic pressure, LA mean pressure and trans-mitral gradient were similar. Post procedure complications were not different in both the groups.

Conclusion

PTMC for mitral restenosis in patients with prior surgical valvotomy is as effective as in patients with prior PTMC despite older age, higher NYHA class, higher Wilkins score and atrial fibrillation and can be considered in all patients with restenosis irrespective of the type of past procedures done.