Safety and Performance of the Subcutaneous Implantable Cardioverter Defibrillator Detection Algorithm INSIGHTTM in Pacemaker Patients.

BACKGROUND: The use of the S-ICD is limited by its inability to provide backup pacing. Combined use of the S-ICD with a pacemaker may be a good choice in certain situations, yet current experience concerning the compatibility is limited. The goal of this study was to determine the safety and efficacy of the S-ICD in patients with a pacemaker. METHODS: A total of 74 consecutive patients with a bipolar pacemaker were prospectively enrolled. First, surface rhythm strips were recorded in all possible pacemaker stimulation modes, to screen for T-wave oversensing (TWOS). Second, a S-ICD functional dummy was placed epicutaneously on the patient in the typical implant position. The same standardized pacing protocol was used as mentioned above, and every stimulation mode was recorded via S-ECG in all vectors. RESULTS: In 16 patients (21.6%), programmed stimulation would have led to VT/VF detection. Triggered episodes were due to counting of the pacing spike(s), QRS complex, premature ventricular contractions, and/or additional TWOS. Three cases triggered in the bipolar stimulation mode. Oversensing was associated with lung emphysema and a reduced QRS amplitude in the S-ECG. CONCLUSION: The combination of an S-ICD and a pacemaker may lead to inadequate shock delivery due to oversensing, even under programmed bipolar stimulation. Oversensing cannot be sufficiently predicted by the screening tool in pacemaker patients. Testing with an epicutaneous S-ICD dummy in all vectors and stimulation settings is recommended in patients with pre-existing pacemakers.

[Novel endoscopic antireflux procedures - time for critical appraisal]. / Dags för kritisk bedömning av nya minimalinvasiva antirefluxtekniker.

GERD is the most prevalent gastrointestinal disorder in the Western world and the extent of anatomic alterations underlying the mechanisms of GERD can be viewed upon as a spectrum from a single anatomic alteration (e.g.  incompetent lower esophageal sphincter) to multiple anatomic alterations, such as diaphragmatic hiatal hernia. The degree of anatomic aberrations also seem to correlate with the complications of GERD. Since GERD is a heterogenous disease, it can be argued that its treatment should be individualized. The medical and surgical therapies have been the mainstay of long-term treatment of GERD, but during recent decades several Food and Drug Administration (FDA)-approved devices have become available for endoscopic treatment of GERD, thus potentially filling the alleged therapeutic gap between medication and surgery. Endoscopic treatment options are now considered appropriate treatment in particular in patients early in the GERD spectrum. However, serious methodological concerns can be raised regarding the scientific documentation behind all of these devices, despite the fact that they are vigorously marketed. This article outlines the basic principles and guidelines for the current and future documentations of such devices, which might be helpful for the clinician in selecting the most accurate long-term therapeutic alternative for patients with chronic GERD.

[Management of patients with gastroesophageal reflux disease can be optimized]. / Gastroesofageal refluxsjukdom ­ gammal bekant med nya ansikten.

Gastroesophageal reflux disease (GERD) often requires lifelong treatment to return to and maintain a normal quality of life. Proton pump inhibitors (PPIs) offer effective medical treatment and can be used for a long time with good safety margins. The diagnostic criteria for GERD must be strictly based on current guidelines and the need for maintained treatment must be regularly evaluated. When medical treatment fails (> 20%), the patient should be offered a consultation with a specialist in the field. Too many patients who are currently treated with PPI for suspected GERD ultimately require treatment with a completely different diagnosis in focus. The investigation and treatment options are several and well-defined in the event of PPI failure in patients with well documented GERD. The indications for surgical treatment are well established, but this treatment option is likely underused today.

[Significant over- and misuse of PPIs]. / Stor överförskrivning och ökat bruk av protonpumpshämmare.

PPIs (Proton-pump inhibitors) offers the best treatment for acid related diseases. The predominant indications for PPI prescription are: GERD eradication of H. pylori-infection in combination with antibiotics H. pylori-negative peptic ulcer  healing of and prophylaxis against NSAID/COXIB--induced gastroduodenal lesions  acid hypersecretory states such as Zollinger-Ellisons syndrome. The market for PPIs continues to expand in most countries. A significant over- and misuse of PPIs prevails in hospital care as well as in general practice. The predominant reasons for and mechanisms behind the over- and misuse of PPIs are well recognised. The most important consequences of this overprescription of PPIs are increasing medical costs and risk for long-term adverse side effects. Continued education and dedicated information are key factors to guide physicians, medical personnel and patients to adopt to generally accepted principles for and balanced use of PPIs.

Laparoscopic Heller myotomy or pneumatic dilatation in achalasia: results of a prospective, randomized study with at least a decade of follow-up.

BACKGROUND AND OBJECTIVES: The most efficient long-term treatment strategy for achalasia has yet to be established. This study compared the long-term results (≥ 10 years) after either pneumatic dilatations or laparoscopic myotomy using treatment failure as the primary outcome. Secondary objectives were; the frequency and degree of dysphagia and effects on health-related quality of life (QoL). PATIENTS AND METHODS: Out of the 53 patients with achalasia who were initially randomized to either laparoscopic myotomy with a posterior partial fundoplication (LM) or repetitive pneumatic dilatation (PD), 43 remained for scrutiny after a median observation period of 170 months (LM; n = 20 and PD; n = 23). RESULTS: At the follow-up of 60 months, 10 patients (36%) in the PD group and two patients (8%) in the LM group were classified as treatment failures (p = 0.016). At the latest follow-up time point (≥ 10 years), the corresponding numbers were 13 (57%) and 4 (20%), respectively. The Kaplan-Meier analysis of the cumulative incidence of treatment failure revealed a significant advantage of LM over the dilatation strategy (p = 0.036)). QoL assessed by the generic instrument PGWB and the more disease-specific instrument GSRS revealed scores which were similar in the two study groups with no obvious changes over time. Reflux was better controlled in the LM group (p = 0.02 regarding PPI consumption). CONCLUSIONS: After more than a decade of follow-up, laparoscopic myotomy reinforces its superiority over repetitive pneumatic dilatation treatment strategy in the management of newly diagnosed achalasia.

Phase response curves for models of earthquake fault dynamics.

We systematically study effects of external perturbations on models describing earthquake fault dynamics. The latter are based on the framework of the Burridge-Knopoff spring-block system, including the cases of a simple mono-block fault, as well as the paradigmatic complex faults made up of two identical or distinct blocks. The blocks exhibit relaxation oscillations, which are representative for the stick-slip behavior typical for earthquake dynamics. Our analysis is carried out by determining the phase response curves of first and second order. For a mono-block fault, we consider the impact of a single and two successive pulse perturbations, further demonstrating how the profile of phase response curves depends on the fault parameters. For a homogeneous two-block fault, our focus is on the scenario where each of the blocks is influenced by a single pulse, whereas for heterogeneous faults, we analyze how the response of the system depends on whether the stimulus is applied to the block having a shorter or a longer oscillation period.

The HLA-DQß1 insertion is a strong achalasia risk factor and displays a geospatial north-south gradient among Europeans.

Idiopathic achalasia is a severe motility disorder of the esophagus and is characterized by a failure of the lower esophageal sphincter to relax due to a loss of neurons in the myenteric plexus. Most recently, we identified an eight-amino-acid insertion in the cytoplasmic tail of HLA-DQß1 as strong achalasia risk factor in a sample set from Central Europe, Italy and Spain. Here, we tested whether the HLA-DQß1 insertion also confers achalasia risk in the Polish and Swedish population. We could replicate the initial findings and the insertion shows strong achalasia association in both samples (Poland P=1.84 × 10(-04), Sweden P=7.44 × 10(-05)). Combining all five European data sets - Central Europe, Italy, Spain, Poland and Sweden - the insertion is achalasia associated with Pcombined=1.67 × 10(-35). In addition, we observe that the frequency of the insertion shows a geospatial north-south gradient. The insertion is less common in northern (around 6-7% in patients and 2% in controls from Sweden and Poland) compared with southern Europeans (~16% in patients and 8% in controls from Italy) and shows a stronger attributable risk in the southern European population. Our study provides evidence that the prevalence of achalasia may differ between populations.

Treatment of achalasia with laparoscopic myotomy or pneumatic dilatation: long-term results of a prospective, randomized study.

BACKGROUND: This study compares the long-term results of pneumatic dilatations versus laparoscopic myotomy using treatment failure as the primary outcome. The frequency and degree of dysphagia, the effects on quality of life (QoL), and health economy were also examined. METHODS: Fifty-three patients with achalasia were randomized to laparoscopic myotomy with a posterior partial fundoplication [laparoscopic myotomy (LM) n = 25] or repetitive pneumatic dilatation [pneumatic dilatation (PD) n = 28]. The median observation period was 81.5 months (range 12-131). RESULTS: At the minimal follow-up of 5 years, ten patients (36%) in the dilatation group and two patients (8%) in the myotomy group, including two patients lost to follow-up (one in each arm), were classified as failures (p = 0.016). The cumulative incidence of treatment failures was analyzed by survival statistics. Taking the entire follow-up period into account, a significant difference was observed in favor of the LM strategy (p = 0.02). Although both treatments resulted in significant improvements in dysphagia scores, LM was significantly favored over PD after 1 and 3 years, but not after 5 years. Health-related QoL assessed by the personal general well being score was higher in the LM group after 3 years, but the difference was not fully statistically significant at 5 years. Direct medical costs during the entire follow-up period were in median $13,421 for LM as compared to $5,558 for PD (p = 0.001). CONCLUSIONS: This long-term follow-up of a randomized clinical study shows that LM is superior to repetitive PD treatment of newly diagnosed achalasia, albeit that this surgical strategy is burdened by high initial direct medical costs. www.ClinicalTrials.gov NCT 02086669.

Activation process in excitable systems with multiple noise sources: Large number of units.

We study the activation process in large assemblies of type II excitable units whose dynamics is influenced by two independent noise terms. The mean-field approach is applied to explicitly demonstrate that the assembly of excitable units can itself exhibit macroscopic excitable behavior. In order to facilitate the comparison between the excitable dynamics of a single unit and an assembly, we introduce three distinct formulations of the assembly activation event. Each formulation treats different aspects of the relevant phenomena, including the thresholdlike behavior and the role of coherence of individual spikes. Statistical properties of the assembly activation process, such as the mean time-to-first pulse and the associated coefficient of variation, are found to be qualitatively analogous for all three formulations, as well as to resemble the results for a single unit. These analogies are shown to derive from the fact that global variables undergo a stochastic bifurcation from the stochastically stable fixed point to continuous oscillations. Local activation processes are analyzed in the light of the competition between the noise-led and the relaxation-driven dynamics. We also briefly report on a system-size antiresonant effect displayed by the mean time-to-first pulse.

Supportive nutrition on recovery of metabolism, nutritional state, health-related quality of life, and exercise capacity after major surgery: a randomized study.

BACKGROUND & AIMS: The aim of this study was to investigate whether specialized supportive enteral and parenteral feeding have superior effects compared to oral nutrition on recovery during long-term postoperative treatment of cancer patients with preoperative weight loss and reduced maximum exercise capacity. METHODS: One hundred twenty-six patients referred for resection of the esophagus (n = 48), stomach (n = 28), or pancreas (n = 50) were considered to be included before operation. Included patients (n = 80) received supportive enteral or parenteral nutrition postoperatively at home corresponding to 1000 kcal/d until the patients did not wish to continue with artificial nutrition for any reason. Patients randomized to oral nutrition only served as control subjects. Caloric intake, body composition (dual-energy x-ray absorptiometry), and respiratory gas exchanges at rest and during exercise were measured including health-related quality of life. RESULTS: Survival and hospital stay did not differ among the groups, whereas overall complications were higher on artificial nutrition (P < .05). Changes in resting energy expenditure and biochemical tests did not differ during follow-up among the groups. Body weight and whole body fat declined similarly over time in all groups (P < .005), whereas lean body mass was unchanged during follow-up compared to preoperative values. Maximum exercise capacity and maximum oxygen consumption were normalized within 6 months postoperatively in all groups. There was no difference in recovery of food intake among the groups. Parenteral feeding was associated with the highest rate of nutrition-related complications, whereas enteral feeding reduced quality of life most extensively. CONCLUSION: After major surgery, specialized supportive enteral and parenteral nutrition are not superior to oral nutrition only when guided by a dietitian.

Leakage testing at the time of surgical oesophageal myotomy.

BACKGROUND: Surgical myotomy is a well-established and validated method to treat severe gastro-oesophageal motor disorders such as achalasia. The benign character of these diseases further substantiates the importance of operating with greatest possible safety margins. We presently report our experiences with the use of perioperative leakage testing. MATERIALS AND METHODS: Thirty-seven consecutive patients are reported of whom 30 had a laparoscopic, 3 a thoracoscopic and 4 an open operation. The indications for an operation were in 3 patients oesophageal spasm, in 30 patients newly diagnosed achalasia and 4 patients had an open reoperation due to a previous incomplete myotomy plus epiphrenic diverticulum. Thirty patients had a perioperative endoscopy with gas insufflation and a leakage test, whereas the others did not. RESULTS: A previously unrecognised oesophageal mucosal tear was discovered during the test and repaired in 4 of the 30 tested cases whereafter everyone had an uneventful postoperative recovery. Among the remaining 7 untested patients, 3 developed clinical signs of leakage of whom 1 had an immediate reoperation. The postoperative courses were in all those prolonged and complicated. CONCLUSION: Perioperative use of endoscopy at the time of completion of the surgical myotomy is a useful tool to document leakage. Thereby the safety profile of the operation can be further enhanced.