Radiofrequency catheter ablation in patients with common atrial flutter

BACKGROUND: Type 1 atrial flutter is produced by a reentry circuit located in the right atrium that can be interrupted applying radiofrequency in the inferior cava-tricuspid valve isthmus. AIM: To report our experience in the treatment of atrial flutter with radiofrequency ablation. PATIENTS AND METHODS: Nine patients (eight male) whose ages ranged from 6 to 72 years old were studied. Two patients had an operated congenital cardiopathy, two had high blood pressure, one was subjected previously to radiofrequency ablation due to a left paraspecific pathway, one developed a cardiac failure secondary to tachycardia and three did not have evidences of cardiopathy. RESULTS: In two patients, atrial flutter was not interrupted. In the other seven patients, radiofrequency ablation was successful. There were three relapses in the first month after the procedure, of these, two patients were successfully treated again. After a mean follow up of 4.5 months, these patients are asymptomatic and without antiarrhythmic drugs. Analysis of obtained signals, showed that radiofrequency that interrupted atrial flutter always occurred in zones of double potentials. CONCLUSIONS: Radiofrequency ablation is an effective treatment for atrial flutter and the zone of successful ablation is associated to the presence of double atrial potentials.     

Utility of the radial-deviated, thumb-abducted lateral radiographic view for the diagnosis of hamate hook fractures: case report

Data from all 225 women operated on for ectopic pregnancy in 1992-1994 at Sahlgrenska University Hospital were collected and compared with three previous cross-sectional investigations from our hospital (1975-1979, 1981-1982 and 1986-1987) in order to evaluate the extent to which surgical treatment and post-operative complications have changed over a 20 year period. Laparoscopic surgery, which was not possible in the 1970s, was used in almost 85% of the ectopic pregnancies in 1992-1994. Conservative treatment was still the most frequently used technique. The complication rate was 1.2% in 1975-1979 when only laparotomies were carried out. After the introduction of laparoscopic surgery (1986-1987), the complication rate rose significantly (7.3%) and continued to increase even when this procedure was established as routine (14.2% in 1992-1994). Post-operative complications were most frequent after conservative laparoscopic surgery (24.4%) while there were no complications after laparotomies. In spite of increasing complication rates the frequency of patients in pre-shock, as well as the proportion of patients with heavy intra-abdominal bleeding and tubal rupture, decreased over time.     

Cystoid macular edema associated with latanoprost in aphakic and pseudophakic eyes

PURPOSE: To describe four patients who developed cystoid macular edema shortly after onset of treatment with latanoprost. METHOD: Retrospective review of medical records of patients with open-angle glaucoma who developed cystoid macular edema shortly after starting latanoprost. RESULTS: The use of topical latanoprost was temporally related to the development of cystoid macular edema in four patients (six eyes; two aphakic eyes and four pseudophakic eyes). Cystoid macular edema resolved in all patients after latanoprost was discontinued. CONCLUSIONS: Cystoid macular edema is a potential complication of latanoprost therapy. Further observations are needed to determine if the risk of cystoid macular edema is limited to or greatest in patients who are pseudophakic or aphakic.     

Macular hole surgery without using adjunctive additives

BACKGROUND AND OBJECTIVE: To evaluate the efficacy of performing surgical techniques for macular holes without using adjunctive additives. PATIENTS AND METHODS: A prospective study was completed of consecutive eyes treated for macular holes of 1 year or less duration that had not had previous vitreous surgery. The best-corrected visual acuity and hole flattening were determined. RESULTS: Postoperative flattening of the hole was achieved in 39 (91%) of 43 eyes, with at least a 50% reduction of the minimum resolvable visual angle (3-line visual increase) in 65% of the eyes and a final vision of 20/40 or better in 40% of the eyes during the follow-up interval (mean 10.6 months). CONCLUSIONS: The success rate of current macular hole surgical techniques suggests that adjunctive additives may not be necessary for most cases. Thus, new treatment modalities need to be evaluated with carefully controlled studies.     

Mucosal iron retention and plasma iron absorption in the duodenum and jejunum of dogs

The electroretinograms (ERGs) from 14 patients with proliferative diabetic retinopathy were recorded before and after peripheral retinal ablation by photocoagulation. It was expected that the ERG would be reduced in amplitude in proportion to the area of retina destroyed by the treatment. The ablation treatment, carried out in a standard manner in each patient, resulted in a decrease of ERG amplitude that varied from 10 to 95% among the patients, and caused an increase in ERG latency and implicit time in several patients. This suggests a wide variability in the area of retina affected by the treatment, and the possibility of an effect of the procedure on adjacent untreated retina in some diabetic patients.     

Cause of death in men diagnosed with prostate carcinoma

Interrelations between QRS morphology, duration, and HV interval changes in a model of "complete" bundle branch block following right bundle branch radiofrequency ablation have not been subjected to systematic study. This article describes these interrelations in patients who underwent right bundle ablation. Over a period of 42 months, 16 patients underwent radiofrequency ablation of the right bundle for treatment of bundle branch reentrant tachycardia. All 16 patients had prolonged HV interval at baseline (minimum = 60 ms; mean = 68 +/- 8 ms). After ablation, one patient developed complete heart block; the remaining 15 patients developed complete right bundle branch block (RBBB) and further prolongation of the HV interval (increment = 24 +/- 16 ms). In 14 of these 15 patients, QRS duration was 138 +/- 26 ms before ablation and increased to 168 +/- 13 ms after ablation. In the remaining patient, the QRS duration was 160 ms before ablation and shortened to 144 ms following ablation despite further HV prolongation. Larger increases of HV interval after ablation were associated with smaller or negative changes in QRS duration (r = -0.77). Three was a direct relationship between QRS duration at baseline and the increment in HV interval after ablation (r = 0.70), and an inverse relationship between QRS duration before and after ablation (r = 0.84). Radiofrequency ablation of right bundle may be associated with an increase in HV interval and QRS duration. However, HV interval prolongation is not necessarily associated with QRS duration widening. A large change in HV interval is more likely to be associated with an already prolonged QRS duration before ablation and a lesser increase or even decrease in QRS duration after ablation. A shorter QRS duration before ablation is associated with a smaller HV interval increase following ablation but a greater increment in QRS duration. These findings are consistent with the concept that narrowness of QRS duration is due to synchronized activation of ventricular endocardium; whereas, QRS duration widening seen with His-Purkinje damage is due to reduced synchronization of endocardial activation.     

An additional variant of the persistent primitive trigeminal artery: accessory meningeal artery--antero-superior cerebellar artery anastomosis associated with moyamoya disease

Neuropathy is a frequent complication in diabetes mellitus. Since the involvement of the autonomic nervous system indicates a poor prognosis, early detection and subsequent management are important. Analysis of heart rate variability (HRV) provides a quantitative measure of sympathovagal modulation activities on the heart and has been proven to be useful for the early assessment of the diabetic autonomic neuropathy. We recently developed a simple method of measuring pulse wave velocity (PWV) to evaluate sympathetic nervous activity in the vascular system. In this paper, we examined 33 diabetic patients with and without peripheral neuropathy (15 and 18 respectively) using these methods. In time domain analysis, the mean heart rate, standard deviation and coefficient of variation of HRVs significantly differed between these two groups, whereas the indices of PWVs did not show a significant difference. In frequency domain analysis of HRV, both low and high frequency components were decreased, and the low frequency component in normalized unit did not increase after standing in patients with peripheral neuropathy. We previously reported that the mean PWV decreased after standing in patients with diabetic neuropathy. This disagreement suggests that beta sympathetic dysfunction precedes alpha sympathetic dysfunction in diabetic neuropathy.     

Refractory intraocular pressure increase after photorefractive keratectomy

A patient with developmental angle anomaly developed a corticosteroid-induced refractory increase in intraocular pressure (IOP) after photorefractive keratectomy (PRK). Trabeculectomy was required to reduce the pressure. Although rare, corticosteroid-induced refractory IOP increase is a serious complication of PRK and may necessitate trabeculectomy. More frequent monitoring of IOP in post-PRK patients and a re-evaluation of postoperative treatment are indicated.     

Distraction osteogenesis in congenital limb length discrepancy: a review

This paper reviews the technique of callotasis used to correct limb length discrepancy due to congenital causes. Many more lower than upper limb lengthening procedures have been reported. Despite the low complication rate reported by the originators of the technique, patients undergoing limb lengthening because of congenital problems are at significant risk of pin tract sepsis, joint contracture, nerve palsies, angular deformities and fracture through the regenerate bone. A minority of studies focus specifically on limb lengthening for congenital defects. Most series simply include some congenital patients, but it is difficult to retrieve the data, and to generalize from them. The amount of lengthening with an acceptable complication rate should not exceed 25%; of the initial bone length. Even using circular frames with small pins, practically all patients may be expected to develop at least one complication each, ranging from pin tract infection to the necessity of carrying out additional unplanned operative procedures either during or after the treatment period. The prevalence of major complications seems to be correlated with the complexity and the duration of the treatment. The functional outcome and the psychological problems associated with a lengthy procedure, which may require long periods of repeated hospitalization, have only rarely been studied. However, it appears that prolonged strength loss is frequent, and that significant psychological morbidity is experienced. Patients and their families should be counselled before and during the procedure on these lesser known aspects of callotasis lengthening.     

Recurrent bronchogenic cyst with rupture into the pericardium. A case report

A case of tamponnade due to intrapericardial rupture of a recurrent bronchogenic cyst, presenting as pericarditis, is described. This case is unique because it demonstrates the possibility of rupture of a bronchogenic cyst into the pericardium and by the unusual mode of presentation. It also shows that bronchogenic cysts may recur many years after incomplete ablation. Bronchogenic cysts are benign dysembrioplasic formations characterised by their respiratory epithelial lining. The usual presentation in the adult is by haemorrhage or infection, but our case shows that recurrent pericarditis without an obvious cause may be due to bronchogenic cyst, which should be systematically excluded. The diagnosis suspected after medical imaging (chest X-ray, scanner, magnetic resonance imaging) is confirmed by histology. Total surgical ablation is the treatment of choice and may be curative.     

Possibilities and limits of intramedullary Kirschner wire osteosynthesis in treatment of metacarpal fractures

Extrasystoles and both supraventricular and ventricular tachycardias may occur as a complication of almost any underlying cardiac disease and many extracardiac causes; on the other hand, also a patient without any detectable structural heart disease may present with these arrhythmias. Refined mapping techniques of the intracardiac conduction process have let to important new informations about the pathophysiology of sustained tachycardias (focal impulse formation, macro-reentry) with practical consequences, for example when ablation of these arrhythmias by radiofrequency catheter ablation is considered. Cardiac arrhythmias may lead to both typical and atypical symptoms. Finally, the patient at risk of sudden cardiac death is characterized. One needs to differentiate patients who have survived a life-threatening event of ventricular tachycardia or have been successfully resuscitated from cardiac arrest (both situations usually need life-long antiarrhythmic interventions for secondary prophylaxis) from patients who also are at high risk, however, are asymptomatic until now. For the latter population, symptoms due to extrasystoles or assessment of the severity of ventricular ectopic beats by the Lown classification are of minor importance; most emphasis in this regard, however, must be placed on the type and severity of underlying cardiac disease.     

Low energy fluence CO2 laser treatment of lymphangiectasia

Lymphangiectasia is an uncommonly reported complication of lymphatic insufficiency. These dilatations of lymphatic vessels may be symptomatic, necessitating treatment. While CO2 laser ablation has been used with success in the treatment of lymphangiectasia, it is infrequently reported and previous laser protocols have relied on high irradiances. The successful use of low fluence CO2 laser in the treatment of multiple lymphangiectases on the lower limb of a middle-aged Caucasian woman with unilateral chronic lymphoedema is described.     

Venous access in oncology

INDICATIONS: Many treatments administered to cancer patients require venous access either via a peripheral vein or a larger central vein at the risk of local or systemic infection, thrombus formation or venous occlusion and dysfunction. PRECAUTIONS: Insertion of a central catheter is an invasive procedure which must be conducted under conditions of rigorous asepsia. Strict rules based on well-defined protocols must be applied throughout its use. INFECTIOUS COMPLICATIONS: Local or systemic infectious complications account for 18 to 25% of all nosocomial infections and are often related to colonisation of the puncture site by a Gram positive germ. In case of infection, ablation of the central catheter is not mandatory for diagnosis or antibiotic treatment. THROMBUS FORMATION: Reported at varying frequencies in the literature from 4 to 42%, thrombus formation is unpredictable and often difficult to diagnose. Anticoagulants or fibrolytic agents are indicated but it may also be necessary to withdraw the catheter. MECHANICAL COMPLICATIONS: Displacement, rupture, obstruction and extravasation are frequent complications. Back flow must be checked in all venous accesses and free flow carefully verified. The access must remain patent throughout the period of use, guaranteed by a standard heparinization and rinsing protocol. UNDENIABLE PROGRESS: This complications must not mask the important progress achieved with the use of central venous access for specific and symptomatic treatment in cancer patients.     

Catheter ablation for atrial flutter and fibrillation. An effective alternative to medical therapy

Atrial flutter and atrial fibrillation are common arrhythmias that can be difficult to manage clinically. In many patients, these conditions are refractory to pharmacologic therapy because of drug failure or intolerance. Radiofrequency catheter ablation may be a reasonable alternative in patients with typical atrial flutter. The procedure has a high initial success rate and a low complication rate. However, recurrence after ablation is common, and a second treatment session may be needed. In selected patients with atrial fibrillation, radiofrequency ablation can be useful for rate control. However, its use in curing chronic fibrillation is still experimental. The procedure involves insertion of a pacemaker, anticoagulation therapy is still needed in most patients, and the need for antiarrhythmic medication may not be obviated.     

Hypoparathyroidism--presenting 40 years after thyroid surgery

BACKGROUND: Latanoprost represents a new therapeutic option in the treatment of chronic open angle glaucoma. It has only recently been reported for the first time that latanoprost caused cystoid macular edema in pseudophakic patients. CASE REPORT: A 60-year-old pseudophakic patient who suffered from a 10-year history of glaucoma, revealed a cystoid macular edema on fluorescence angiography after 10 days of treatment with latanoprost. One week after cessation of latanoprost therapy the cystoid edema in fluorescence angiography had resolved and the vision improved from 0.4 to 0.8. CONCLUSIONS: With respect to this severe complication, latanoprost should be used with great care and in clear indications, particularly in patients with risk of blood-aqueous leakage e.g. pseudophakic patients.     

原颗粒边界问题和热处理裂纹形成原因的研究

业已证实,粉末高温合金中原颗粒边界（PPB）问题严重影响合金性能。本文研究了FGH95合金PPB对淬火裂纹的影响,通过对淬火开裂后样品断口形貌、析出相类型、表面俄歇谱化学成分分析找出淬火时裂纹形成的原因和控制因素。
实验结果和分析表明;造成淬火裂纹形成的两种机制,开裂严重的是由于PPB碳化物及在其外表面形成富氧层破坏合金的连续性,促使沿原颗粒边界断裂。开裂不严重的是由于γ相界析出大块γ'相其周围贫A1,Ti区形成易氧化层,促使沿γ相界断裂。
基于两种机制的提出,可以较好地说明影响淬火裂纹形成的主要原因是氧的污染和不适宜的淬火冷却速度。     

A perspective on the ESVEM trial and current knowledge: catheter ablation for ventricular tachyarrhythmias

Although an effective and potentially curative technique for treating idiopathic ventricular tachycardia, map-guided transcatheter radiofrequency ablation is far from optimal for ventricular tachyarrhythmias in patients with advanced ischemic or other types of organic heart disease. First, this technique can be applied only to a minority of patients with structural heart disease, who can tolerate relatively long episodes of induced ventricular tachycardia necessary for mapping and successful ablation. Second, the success rate is lower and recurrence higher in patients with organic heart disease. Finally, for patients who lose consciousness during tachycardia or who present with prehospital cardiac arrest, transcatheter radiofrequency ablation is inappropriate as definitive treatment. At best, it is palliative and may be used to suppress relatively slow, frequent, or incessant ventricular tachycardias but does not obviate the need for other therapies such as cardioverter-defibrillator implantation or antiarrhythmic drug therapy.     

Dislocation in total hip arthroplasties

In a series of 1,443 total hip arthroplasties performed between 1970 and 1975, dislocation was the most frequent complication and its incidence was found to be increasing. Dislocatin was frequently associated with component malposition that the surgeon was not aware of at the time of surgery and was relatively frequent among less experienced surgeons. It was especially frequent if the patient had had previous hip surgery and was related to the difficulty of the surgery rather than the primary hip disease. Increasing incidence was associated with change in operative technique and less stringent patient selection. Dislocation was 2 1/2 times more frequent if trochanteric osteotomy was not performed. The tip of the greater trochanter was moved significantly closer to the center of the prosthetic head in the patients who dislocated. Traction for up to three weeks did not lower the incidence of subsequent dislocation compared with mobilization of the patients as soon as tolerated after dislocation. Surgery was effective in preventing further dislocations in patients with recurrent dislocation and component malposition. The use of an articulated prosthesis is not recommended.     

Peripheral arterial complications after heart catheterization

After diagnostic and interventional cardiac catheterization, local vascular complications at the arterial entry site must be expected. With respect to the method applied for catheterization and the puncture site, the type of complications may vary. With transfemoral approach a large variety of vascular complications have to be feared, mostly in the form of bleeding complications and hematomas, arterial dissections or occlusions, pseudoaneurysms and AV-fistulas. Each of these complications may have the potential for serious morbidity. When cardiac catheterization is performed via the arteries of the arm (either in the classical Sones technique by arterial cutdown to the brachial artery or by direct puncture of the brachial or radial artery) vascular occlusions will mostly occur as local vascular complications. These occlusions can often be managed conservatively or by a surgical procedure. The incidence of a vascular complication is mainly dependent on patient-related (sex, age, height, weight, arterial hypertension, diabetes, presence of peripheral vascular disease and compliance of the patient after withdrawal of the sheath) and procedure-related (arterial access site, diagnostic or interventional study, sheath size, periprocedural anticoagulation, duration of intra-arterial sheath placement, faulty puncture technique, operator skill) factors. In addition, the definition of a complication, the publication year of a certain study and the technique used for identification of complications seem to play a role for the reported incidence of peripheral vascular complications after cardiac catheterization. Currently, incidences of 0.1 to 2% for significant local vascular complications after diagnostic transfemoral catheterization are reported, after interventional transfemoral treatment 0.5 to 5% and after complex procedures using large sheath sizes with periprocedural anticoagulation (directional atherectomy, IABP, left-heart assist, valvuloplasty) up to 14%. Following transbrachial and transradial catheterization, local vascular complications at the entry site amount to 1 to 3% after diagnostic and 1 to 5% after interventional procedures. Local vascular complications may be diminished by a cautious and sensitive puncture technique with additional care in patients at higher risk for vascular complications (females, prediagnosed peripheral vascular disease, mandatory anticoagulation, necessity for large sheaths). By using smaller sized catheters and an adequate, defensive anticoagulation regimen, the rate of arterial access site complications may be reduced. Proper methods for achievement of hemostasis as well as a close and careful observation after sheath withdrawal are required.     

Hysteroscopic endometrium ablation to avoid hysterectomy in "high risk" patients

Hysteroscopic endometrial ablation under maximal anaesthesiological surveillance was performed in 34 high-risk patients to avoid hysterectomy. It was a collective of patients with heavy thrombo-embolic or thrombotic disease, either under permanent anticoagulation due to residual disease or multiple endoprosthetic treatment, or with endogenous coagulopathy. In all these women, hysterectomy was either a relative or an absolute contraindication. In 22 patients, treatment resulted in complete amenorrhoea or at least hypomenorrhoea (without menometrorrhagia) respectively cyclic spotting. In 6 further patients, amenorrhoea was achieved after a repeat procedure. Endometrial ablation was thus successful in 28 of 34 cases. In these patients, hysterectomy with the risk of major or even lethal complications, could thus be avoided. Hysterectomy, however, had to be performed in 2 women with extensive adenomyosis uteri interna. Within two respectively three years after endometrial ablation, two other patients died from causes unrelated to the surgical intervention (cardiac infarction, cerebral haemorrhage). Follow-up ranged from 1 to 5 years. Hysteroscopic endometrial ablation proved an effective therapeutic option in this selected group of patients. Other indications require further study.