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Introduction: Usage of vacuum therapy and dry needling in physical therapy management of musculoskeletal cases have gained increasing usage but there is a limited number of literatures regarding its effect. This study determines the effect size of the interventions, which are vacuotherapy and dry needling as adjunct treatment to exercises, performed in a local PT clinic to musculoskeletal cases in three different treatment sessions with a week gap in between. Methods: The study is a retrospective-cohort where sampling was purposive in gathering historical patient charts. The numerical pain rating scales and relevant range of motion in the musculoskeletal cases were collected for analysis. Results: Results showed large significant reduction in pain scale between sessions but no significant changes in all ranges of motion across different anatomically categorized musculoskeletal cases. Discussions: The results of this study imply that using vacuum therapy and dry needling as adjunct to therapeutic exercises can reduce pain intensities significantly but not ROM. Further research is recommended regarding effects of these tools for ROM and their retention of effects.

Communicative competence is the learner’s ability to use language to communicate successfully. This descriptive-comparative study assessed the communicative competence of 248 senior high school students in a private academic institution in Bacolod City, Philippines. Data were gathered using the researcher-made essay test and extemporaneous speaking questions. Significant findings revealed that the respondents were competent in written and oral communication, with mean scores of 44.07 and 47.03, respectively. However, when grouped according to sex, female students performed better than their male counterparts based on the levels of linguistic and discourse competence. When grouped according to strand, the mean scores of the respondents vary from ‘moderate’ to ‘good’ in both areas. Using Independent T-test, the data further indicated significant differences when the respondents are grouped according to sex in terms of linguistic and discourse competence. On the contrary, One-Way Analysis of Variance revealed no significant differences for both areas when the respondents are grouped according to strand. Overall, the communicative competence of senior high school students could still be improved. For this reason, a remedial program was proposed to provide additional instruction to aid students’ difficulties concerning communication skills and to ensure that they meet their grade level expectations in English language learning.

Background Inadvertent lead malposition (ILM) in the left ventricle (LV) via the subclavian artery is a rare complication during the insertion of cardiac implantable electronic devices (CIED). If not identified, there is a risk of systemic thromboembolism. Transarterial pacing lead extraction often requires surgical removal and carries high risks of bleeding and thromboembolism, but percutaneous extraction has also been previously described. Case summary A 71-year-old female presented with left homonymous hemianopia on Day 1 post-insertion of a dual-chamber permanent pacemaker (PPM). A computed tomography (CT) angiogram of the brain and aortic arch revealed an acute occlusion of a branch of the right posterior circulating artery (PCA) and a malpositioned pacing lead in the left subclavian artery. Urgent percutaneous removal of the transarterial lead using the retained wire technique was successfully performed. Discussion Inadvertent lead malposition in the arterial system is rare and often requires lead extraction due to systemic thromboembolic complications. The retained wire technique has been previously described for percutaneous transvenous lead extraction and exchange, but to our knowledge, we are the first to report utilizing this technique for transarterial lead extraction. Using a case report, we highlight the utility, safety, and effectiveness of the retained wire technique in extracting a malposition lead in the subclavian artery and LV.

Water quality (WQ) analysis is a critical stage in water resource management and should be handled immediately in order to control pollutants that could have a negative influence on the ecosystem. The dramatic increase in population, the use of fertilizers and pesticides, and the industrial revolution have resulted in severe effects on the WQ environment. As a result, the prediction of WQ greatly helped to monitor water pollution. Accurate prediction of WQ is the foundation of managing water environments and is of high importance for protecting water environment. WQ data presents in the form of multi-variate time-sequence dataset. It is clear that the accuracy of predicting WQ will be enhanced when the multi-variate relation and time sequence dataset of WQ are fully utilized. This article presents the Water Quality Prediction utilising Sparrow Search Optimization with Hybrid Long Short-Term Memory (WQP-SSHLSTM) model. The presented WQP-SSHLSTM model intends to examine the data and classify WQ into distinct classes. To achieve this, the presented WQP-SSHLSTM model undergoes data scaling process to scale the input data into uniform format. Followed by, a hybrid long short-term memory-deep belief network (LSTM-DBN) technique is employed for the recognition and classification of WQ. Moreover, Sparrow search optimization algorithm (SSOA) is utilized as a hyperparameter optimizer of the proposed DBN-LSTM model. For demonstrating the enhanced outcomes of the presented WQP-SSHLSTM model, a sequence of experiments has been performed and the outcomes are reviewed under distinct prospects. The WQP-SSHLSTM model has achieved 99.84 percent accuracy, which is the maximum attainable. The simulation outcomes ensured the enhanced outcomes of the WQP-SSHLSTM model on recent methods.

Defibrillator technology for sudden cardiac death (SCD) prevention now includes the transvenous implantable cardiac defibrillator (ICD), subcutaneous ICD (S-ICD) and wearable cardioverter defibrillator (WCD). ICD use improves survival in patients who survived previous sudden cardiac arrest (SCA) due to ventricular tachycardia (VT)/ventricular fibrillation (VF), as well as in patients who experienced haemodynamically significant VT. It is also currently indicated for primary prevention in ischaemic/non-ischaemic cardiomyopathies, certain congenital heart disease conditions and inherited channelopathies. In this review article, we hope to present an updated review on ICD use for SCD prevention, with a focus on contemporary issues affecting ICD selection. These include: the role of primary prevention ICD in patients with non-ischaemic cardiomyopathy (NICM) in light of the 2016 DANISH (Danish Study to Assess the Efficacy of ICDs in Patients with Non-Ischemic Systolic Heart Failure on Mortality) trial; the role of defibrillator component (CRT-D) in patients receiving cardiac resynchronisation therapy (CRT-P); and the emerging role of cardiac magnetic resonance imaging (cMRI) in particular, the presence of late gadolinium enhancement (LGE), as an important SCD risk predictor. The current use of S-ICD and WCD, including clinical indications, evidence for efficacy and limitations, will also be discussed.

Background Atrioventricular nodal (AVN) ablation with permanent pacemaker (PPM) insertion is indicated for rate control in patients with atrial fibrillation (AF) who remain unresponsive to rate or rhythm control strategies. The leadless PPM (Micra Transcatheter Pacing System [TPS], Medtronic, Minneapolis, MN, USA) has the advantage of eliminating transvenous lead and pacemaker pocket-related complications. The aim of this case series was to determine the outcomes of patients who had undergone combined Micra TPS and AVN ablation, performed via a single femoral approach. Method A retrospective review was undertaken on patients who had undergone concurrent procedures, across two major hospitals in Perth, Western Australia. Procedural details were obtained from a cardiac devices database whilst patient demographics and clinical information were determined from medical records. Results Fourteen (14) patients underwent concurrent Micra TPS insertion and AVN ablation for symptomatic AF. The average age was 73 ± 9.2 years, and 43% of them were males. There was no acute procedural/device related complication. Over a median follow-up duration of 9 months (36% completing 12-month follow-up), there was no incidence of device complications, in particular device dislodgement, malfunction or infection. One patient had a resuscitated ventricular fibrillation (VF) arrest event with new onset cardiomyopathy during follow-up and required Micra TPS removal. One patient died at 33 days post procedure from a non-cardiac cause. Device performance was excellent with stable sensing and pacing thresholds during the follow-up period. Conclusion Our study has shown that combined leadless PPM (Micra TPS) implantation and AVN ablation using a single femoral approach is feasible, with good safety and efficacy profile in the short–medium term. Long-term data involving larger cohorts is needed to confirm the findings of this study and determine the clinical usefulness of this combined approach.

Left atrial appendage (LAA) device occlusion represents a major evolution in stroke prevention for atrial fibrillation (AF). Left atrial appendage device occlusion is now a proven strategy which provides long-term thromboembolic stroke prevention for patients with non-rheumatic AF. Evidence supports its benefit as an alternative to long-term anticoagulation while mitigating long-term bleeding risks and improving cardiovascular mortality. The therapy offers expanded options to physicians and patients negotiating stroke prevention (both primary and secondary prevention), but a good understanding of the risks and benefits is required for decision-making. This review aims to summarise the evolution of LAA device occlusion therapy, current knowledge in the field and a snapshot of current status of the therapy in clinical practice in Australia and around the world.

Biometric systems are growingly used for authentication purposes in various security applications. Face, Fingerprint and Iris are the biometric modalities commonly used in the authentication systems. Simplicity of use, reliability and uniqueness are important characteristics of biometric based authentications. This kind of techniques can solve the typical problem of systems based on use of password which can be forgotten or stolen. Biometric systems plays a significant role in personal, national, and global security. Despite the increase in usage of biometric based systems, these are quiet susceptible to sophisticated spoofing attacks. Various spoofing attacks are present to defeat such biometric authentication systems. To improve the level of security, it is necessary to augment the reliable liveness detection tools as software modules along with the existing authentication systems. This paper targets the countermeasures for the biometric spoofing attacks and also suggests technical measures for implementing the biometric liveness detection systems. The research in this field is very active, with local descriptors. In order to overcome the shortcomings of already existing liveness detection tools, in this work we propose two different feature extraction techniques for software-based liveness detection: Convolutional Networks and Local Binary Patterns. Both techniques were used in conjunction with a Support Vector Machine (SVM) classifier. Dataset Augmentation was used to increase classifier's performance and a variety of preprocessing operations were tested, such as frequency filtering, contrast equalization, and region of interest filtering.

Feature selection is very important as data is created constantly and at an ever increasing rate, it helps to reduce the high dimensionality of some problems. Feature selection as a preprocessing step to machine learning, is effective in reducing redundancy, removing irrelevant data, increasing learning accuracy, and improving result comprehensibility. This work offers comprehensive approach to feature selection in the scope of classification problems, explaining the foundations, real application problems etc in the context of high dimensional data. First, we focus on the basis of feature selection provides an analysis on history and basic concepts. The different types of feature selection methods are discussed and finally analyze the findings.

Alzheimer's Disease (AD) is brain disease which gradually develops over years. It progressively damages the reasoning capability and memory of the affected. There is no current treatment to cure AD. But early diagnosis can prevent the severity of the disease and can improve the quality of life. The identification of discriminative features in brain images leads to accurate diagnosis of AD. This paper presents an analysis of related works done for the classification of AD using different feature extraction, feature selection and classification techniques. The methods used for the classification of AD, their accuracy levels and their advantages are consolidated. Based on the analysis, a new model has been proposed for classification of AD.

Feature extraction simplifies the amount of information needed to describe the properties of an image accurately. This paper measures the performance of a CBIR system based on texture feature against combination of both color and texture feature. A Gray Level Co-occurrence Matrix is calculated for computing the texture feature of an image. Using these textual parameters similar images are extracted from a data set. RGB color space is considered for color feature extraction. Global Color Histogram is generated and calculated color features are represented as one dimensional feature vector. Then we combined both color and texture features to retrieve similar images from the dataset. In both situations Euclidean distance is used to measure the similarity of two images. By this experiment it is found that the system which uses the combination of color and texture has better performance in retrieving similar images from the dataset.

Background The practise of catheter ablation for atrial fibrillation (AF) is increasing rapidly and is recommended as the treatment of choice in many patient subgroups. At present, the efficacy of this procedure has been assessed by means of electrocardiographic recording, intermittent Holter monitoring and evaluation of patient symptoms. We sought to evaluate the true efficacy of this procedure in patients with sophisticated permanent pacemakers capable of continuous long-term cardiac rhythm monitoring. Methods Twenty-five patients (aged 63.7 (9.4), 20 men), seven with persistent AF and 18 with prolonged paroxysmal AF, underwent a mean of 1.7 AF ablation procedures. All the patients had previously been implanted with a pacemaker or atrial defibrillator device. Data were downloaded from the device Holter before catheter ablation and at 2, 4, 6 and 8 months postprocedure(s). The primary outcome measure was AF burden. The secondary outcomes were patient symptom and quality-of-life measures. Results Initial AF burden was 43.8 (35.5)%. After catheter ablation(s), this was significantly reduced at 2 months to 23.8 (35.4)% (p=0.023), at 4 months to 21.4 (34.1)% (p=0.008), at 6 months to 14.5 (28.1)% (p=0.002) and at 8 months to 15.0 (29.4%) (p=0.003). Only nine (36%) of 25 patients demonstrated no recurrence of arrhythmia during follow-up completion, consistent with a long-term cure. Quality-of-life indices showed significant improvement after ablation. Conclusions Catheter ablation for AF significantly improves patient symptoms and reduces AF burden after long-term beat-to-beat monitoring by implanted cardiac pacemaker and defibrillator devices. However, AF recurrence is common after these procedures.

Background: Cardiac resynchronization therapy (CRT) is recommended for patients with NYHA class III–IV refractory heart failure (HF), ejection fraction 120ms. We attempted to identify responders to CRT from echocardiographic (echo) indices of mechanical dyssynchrony in patients with QRS < 150 ms. Methods and results: The study enrolled 51 men and 9 women (mean age: 64.5years) in NYHA class III (n=54) or IV (n=6) presenting with a mean ejection fraction: 25.7%, LV end-diastolic diameter: 69.1mm, and QRS = 121 ± 19 ms. All patients were implanted with a CRT system and followed for 1year. Implantation was preceded and followed by clinical, functional and Doppler (D)-echo evaluation. The primary combined endpoint included 1) death from any cause, 2) HF-related hospitalisations, and 3) NYHA class at 6 months. Before implant, 27 patients had ≥ 1 echo criterion of mechanical dyssynchrony (DES+ group) and 33 had no evidence of dyssynchrony (DES− group). At 12months, 8 patients (4 per group) had died, 7 from HF. As regards the primary endpoint at 6 months, 33 patients (55%) had improved, 10 (16%) were unchanged, and 17 (29%) had deteriorated. Clinical improvement was observed in 19 of 27 DES+ (70%), versus 14 of 33 DES− (42%) patients (P

Objectives The theory of a red blood cell derived nitric oxide (NO) reserve conserving NO bioactivity and delivering NO as a function of oxygen demand has been the subject of much interest. We identified the human coronary circulation as an ideal model system in which to analyse NO metabolites because of its large physiological oxygen gradient. Our objective was to identify whether oxygen drove apportion between various NO metabolite species across a single vascular bed. Methods Plasma and red blood cell NO metabolites were assessed from the left main coronary artery, coronary sinus and pulmonary artery (providing cross heart and cross pulmonary analysis) of healthy subjects under resting conditions and following administration of an inhibitor of NO biosynthesis. Physiological parameters and angiographic data were monitored throughout the study. Results Under baseline conditions we observed significant metabolite flux upon the transit of blood across the coronary and pulmonary vascular beds. Whilst there was no net loss of NO through the coronary circulation ( p =0.0759), plasma nitrite/protein NO (excluding nitrate) ( p =0.0279) and red blood cell sulphanilamide labile signal ( p =0.0143) decreased whereas haemoglobin-bound NO increased three-fold ( p =0.005). These changes across the coronary circulation were reversed through the pulmonary circuit with red blood cell sulphanilamide labile signal ( p =0.0143) and plasma nitrite/protein NO ( p =0.0279) increasing and haemoglobin-bound NO decreasing. Blockade of NO synthesis increased mean arterial blood pressure ( p

Aims The aim of this study is to investigate the safety and effectiveness of Excimer laser-assisted lead extraction in Europe. The final European multi-centre study experience is presented. Method and results The Excimer is a cool cutting laser (50°C) with a wavelength of 308 nm. The energy is emitted from the tip of a flexible sheath and is absorbed by proteins and lipids, 64% of the energy is absorbed at a tissue depth of 0.06 mm. The sheath is positioned over the lead, and the fibrosis surrounding the lead is vaporized while advancing the sheath without damaging other leads. From August 1996 to March 2001, 383 leads (170 atrial, 213 ventricular) in 292 patients (mean age 61.6 years, range 13–96) were extracted at 14 European centres. Mean implantation time was 74 months (3–358). Most frequent indications were pocket infection (26%), non-functional leads (21%), patient morbidity (21%), septicaemia or endocarditis (14%), erosion (5%), and lead interference (8%). Median extraction time was 15 min (1–300). Complete extraction was achieved in 90.9% of the leads and partial extraction in 3.4%. Extraction failed in 5.7% of the leads. Major complications = perforations caused 10/22 (3.4/5.7%) of the failures. Most partially extracted patients were considered clinically successful, as only minor lead parts without clinical significance were left. Femoral non-laser technique was used to remove 8/12 of the non-complication failures. The total complication rate, including five minor complications (1.7%), was 5.1%. No in-hospital mortality occurred. Conclusion Pacing and implantable cardioverter–defibrillator leads can safely, effectively, and predictably be extracted. Open-heart extractions can be limited to special cases. The results indicate that the traditional policy of abandoning redundant leads, instead of removing them, may be obsolete in many patients.

Transvenous left ventricular (LV) leads are primarily inserted "over-the-wire" (OTW). However, a stylet-driven (SD) approach may be a helpful alternative. A new polyurethane-coated, unipolar LV lead can be placed either by a stylet or a guide wire, which can be inserted into the lead body from both ends. The multicenter OVID study evaluates the clinical performance of this new steroid- and nonsteroid eluting lead. The primary endpoint is the LV lead implant success rate after identification of the coronary sinus (CS). Secondary endpoints include complication rate, short- and long-term lead characteristics, overall procedure and LV lead placement duration, total fluoroscopy time, and lead handling characteristics ratings. To date, 96 patients with heart failure (68 +/- 9 years old, 76% men) are enrolled. The CS was identified in 95 patients and, in 85 (88.5%), the LV lead was successfully implanted. The final lead positioning was lateral in 41%, posterolateral in 35%, anterolateral in 18%, and great cardiac vein in 6% of patients. In 70%, the 85 successful implantations, both stylet-driven and guide-wire techniques were used, a stylet only was used in 22%, and a guide wire only in 8%. Mean overall duration of 85 successful procedures was 112 +/- 40 minutes, total fluoroscopy time 28 +/- 15 minutes, and the duration of LV lead placement was 35 +/- 29 minutes. During a 3-month follow-up, the loss of LV capture occurred in three and phrenic nerve stimulation in six patients. The mean long-term pacing threshold is 0.8 V/0.5 ms and pacing impedance is 550 Omega. The OVID data suggest that these new leads are safe and effective. The choice of both OTW and SD techniques during lead implantation offers greater procedural flexibility.

Resynchronisation therapy with biventricular pacing is increasingly accepted as therapy for patients with drug resistant heart failure. The complications of device implantation include those associated with conventional pacing and those specifically related to the positioning of a lead within a branch of the coronary sinus. These complications include unsuccessful implantation, phrenic nerve stimulation, coronary sinus dissection or perforation, and embolic phenomena.

Aims To determine the effect of an endocardial DC shock on the basic electrophysiology of the human atrium if delivered in sinus rhythm. Methods and results A 5J endocardial R wave synchronized DC shock was delivered in 10 patients in stable sinus rhythm during ICD implantation for ventricular arrhythmias. There was no prior history of atrial fibrillation. Monophasic action potential duration (APD) and atrial effective refractory periods (AERP) were evaluated before, 1 min post DC shock, and 15 min post shock. These parameters were assessed at basic cycle lengths and at atrial paced cycle lengths of 600 ms and 400 ms at two right atrial sites; mid lateral right atrial wall (MRLA) and the right atrial appendage (RAA). There were no significant differences in APD 90, AERP or atrial refractory dispersion at any site or drive cycle length before, immediately after or 15 min after shock delivery. Conclusions There are no significant changes in basic electrophysiological parameters following a DC shock delivered in sinus rhythm in patients with no prior history of atrial fibrillation. This suggests that atrial electrical remodelling occurs as a result of atrial fibrillation and is unrelated to shock artefact. (Europace 2003; 5: 33–37)

Background: The effect of left ventricular (LV) systolic function on the long-term left ventricular pacing and sensing threshold is unclear. Methods and Results: We studied the effect of LV ejection fraction (LVEF) on the LV pacing and sensing threshold in 56 patients (mean age: 70.2 ± 10.5 years) underwent permanent LV pacing using a self-retaining coronary sinus lead (Model 1055 K, St Jude Medical, USA). In 49 patients, the LV lead was implanted for conventional pacemaker indication (sick sinus syndrome = 14, heart block = 26 or slow atrial fibrillation = 9). The remaining 7 patients were implanted for congestive heart failure. The LV pacing and sensing threshold, and lead impedance were compared between patients with LVEF 40% (Group 2, n = 28) during implant and at 3-month follow up. The LV pacing lead was successfully implanted in all patients without any lead dislodgement on follow-up. At implant, Group 1 patients had a significant lower R wave amplitude, but similar LV pacing threshold and lead impedance as compared to Group 2. However, at 3-month follow-up, Group 1 patients had a significantly higher LV pacing threshold compared to Group 2 patients. There were no significant differences in the sensing threshold and lead impedance between the two groups. Furthermore, there was also a significant interval increase in LV pacing threshold in Group 1 patients (0.94 ± 0.12 V) after 3 months, but not in Group 2 patients (0.16 ± 0.08 V, p < 0.01). Conclusions: The results of this study suggest that the LV systolic function has a significant impact on the long-term LV pacing threshold. The long-term left ventricular pacing threshold in patients with left ventricular systolic dysfunction increased after implant and was higher than patients with normal left ventricular systolic function.

OBJECTIVE—To determine the importance of rhythm regulation or rate control in patients with permanent atrial fibrillation (AF) and normal left ventricular function. PATIENTS AND INTERVENTIONS—Thirty six patients with a mixed fast and slow ventricular response rate to their AF were randomised to either His bundle ablation (HBA) and VVIR pacemaker (HBA group) or VVI pacemaker and atrioventricular modifying drugs (Med group). Outcomes assessed at one, three, six, and 12 months included exercise duration and quality of life. RESULTS—Exercise duration significantly improved from baseline in both groups. There was no difference in outcome between the groups (Med +40% v HBA +20%, p = NS). The heart rate profile on exercise was similarly slowed in both groups compared to baseline. Quality of life significantly improved in both treatment arms for the modified Karolinska questionnaire (KQ) (Med +50% v HBA +50%, p = NS) and the Nottingham health profile (NHP) (Med +40% v HBA +20%, p = NS). However, for the individual symptom scores of each questionnaire more were improved in the Med group (KQ-Med 6 improved v HBA 4, NHP-Med 3 v HBA 1). Left ventricular function was equally preserved by both treatments during follow up. CONCLUSION—In these patients control of ventricular response rate with either HBA + VVIR pacemaker or atrioventricular modifying drugs + VVI pacemaker will lead to a significant improvement in exercise duration and quality of life. Rhythm regulation by HBA did not confer additional benefit, suggesting rate control alone is necessary for the successful symptomatic treatment of these patients in permanent AF. Keywords: ablation; atrial fibrillation; pacemaker; atrioventricular modifying drugs

OBJECTIVE—To evaluate the incremental antifibrillatory effect of multisite atrial pacing compared with right atrial pacing in patients with drug refractory paroxysmal atrial fibrillation paced for arrhythmia prevention alone. METHODS—In 20 of these patients (mean (SD) age 64 (8) years; 14 female, six male), a single blinded randomised crossover study was performed to investigate the incremental benefit of one month of multisite atrial pacing compared with one month of right atrial pacing. Outcomes included the number of episodes of paroxysmal atrial fibrillation, their total duration obtained from pacemaker Holter memory, and quality of life using a cardiac specific questionnaire (the modified Karolinska questionnaire). RESULTS—Comparing right atrial with multisite atrial pacing, there was no significant change in either the number of paroxysmal atrial fibrillation episodes (mean (SD): right atrial pacing 77 (98) episodes v multisite pacing 52 (78) episodes, NS) or their total duration (right atrial, 4.8 (5.4) days v multisite, 6.3 (9.8) days, NS). Quality of life scores compared with baseline status were equally improved by either pacing strategy (mean percentage improvement: right atrial, 38%, p = 0.003; multisite, 44%, p = 0.003). There was no significant difference in life scores comparing the two pacing modes. CONCLUSIONS—Multisite atrial pacing has no incremental antiarrhythmic effect compared with right atrial pacing in patients paced for drug refractory paroxysmal atrial fibrillation. Quality of life is equally improved with either pacing strategy, with no differences between them. Keywords: multisite atrial pacing; atrial fibrillation; pacing

Background —Atrial fibrillation (AF) is a common problem after CABG. Prevention with prophylactic drug therapy has had limited success, therefore alternative approaches are required. This study investigated the role of biatrial pacing compared with no pacing on AF incidence after isolated first-time CABG. Methods and Results —During surgery, temporary pacing leads were placed in the lateral wall of the right atrium and at the roof of the left atrium in Bachmann’s bundle to allow bipolar pacing and sensing at each site. After surgery, all patients were connected to an external pacemaker (Chorum ELA) that also acted as a Holter monitor. Patients were consecutively randomized to either 4 days of biatrial pacing at a base rate of 80 bpm or to no pacing (control group, base rate 30 bpm). End points included an episode of AF lasting >1 hour on pacemaker Holter, clinically detected AF, intensive care unit (ICU) and hospital stay, and postoperative complications. One hundred thirty patients were randomized. Biatrial pacing significantly reduced both monitored (13.8% versus 38.5%, P =0.001) and clinical (10.8% versus 33.8%, P =0.002) episodes of AF. Median ICU (19 versus 24 hours, P =NS) and mean hospital stay (7.7±6.9 versus 9.7±10, P =NS) did not significantly change. The number of postoperative complications was lower in the biatrial group (13 versus 35, P =0.001). Conclusions —Biatrial pacing after CABG significantly decreases the incidence of AF. This is associated with reduced postoperative complications and a trend toward reduced ICU and hospital stay.

Background : Atrio-ventricular junctional ablation with pacemaker insertion has been shown to improve quality of life in patients with drug refractory paroxysmal atrial fibrillation. It is unknown whether this improvement is secondary to the ablation procedure or to the pacemaker mode utilised. To investigate this we reviewed our experience of implanting a dual chamber rate responsive pacemaker with mode switching (DDDR/MS) alone on quality of life in this patient group. Methods and results : Over a 1-year period, 19 patients (mean age 62±9 years, 13 female) with drug refractory paroxysmal atrial fibrillation (mean duration of symptoms 8.7±7 years, failed 3.1±0.9 anti-arrhythmic drugs, amiodarone in 15) were recruited. Quality of life was assessed at baseline and after 1 month using a cardiac specific questionnaire, the modified Karolinska questionnaire. The mean score for all patients significantly improved by 39% at follow up (baseline 59±24, 1 month 36±24, P =0.001). Individually 15 patients (79%) had an improvement in their score, whilst for 13 patients (68%) their symptoms were sufficiently improved after pacing that ablation was not required. The benefit was maintained to a mean follow up of 12±5 months (score 31±20, P Conclusions : Patients with drug refractory paroxysmal atrial fibrillation, DDDR/MS pacing alone can improve quality of life without concurrent atrio-ventricular junctional ablation in a significant proportion of patients.

The role of atrial overdrive pacing for the suppression of paroxysmal atrial fibrillation remains unclear. To investigate this we have performed a randomised study evaluating the role of an increased atrial base rate in suppressing this arrhythmia in patients implanted with a permanent pacemaker (Chorum ELA) for sick sinus syndrome with previous documented paroxysmal atrial fibrillation. Twenty-seven patients (mean age, 69; 15 female) were randomised to two 3-month single-blinded crossover periods of DDDR pacing. The pacemaker was set with a base rate of 60 bpm (normal) during one period and at 10 bpm (overdrive) above the average heart rate during the other, mean (S.D.) 75+/-7 beats/min (range, 70-96). The fallback algorithm of the pacemaker was activated to record the number and duration of paroxysmal atrial fibrillation episodes. During the overdrive period there was a significant increase in the total duration of atrial pacing (normal 60+/-26% vs. overdrive 72+/-28%, P

Aims To describe the institution of a biventricular pacing programme with particular reference to the implantation procedure and new technological considerations. Methods and Results Analysis of outcomes of a consecutive series of 54 patients undergoing attempted biventricular pacemaker implantation between February 1998 and April 1999. Successful implantation was achieved in 49 of the 54 patients (91%). Five patients required lead repositioning after initial successful implantation. Left ventricular lead pacing thresholds were found to be satisfactory and stable in the long term, with pacing thresholds of 1·3 V, 1·9 V and 1·6 V at implantation, 1 and 3 months, respectively. Left-sided lead function was not dependent on lead position within the tributaries of the coronary sinus. The implantation procedure was found to be safe, although one patient died during long-term follow-up. Conclusion With appropriate previous experience in complex and coronary sinus pacing and with access to up-to-date pacemaker and lead technology, a biventricular pacemaker implantation service can be instituted with good medium-term results.

Aims It has been reported that biatrial pacing can prevent the recurrence of atrial fibrillation. This technique requires a stable coronary sinus (CS) lead position for left atrial pacing. We report our experience of CS pacing with a specifically designed lead [Medtronic 2188 (n= 19)] and active fixation leads [Pacesetter Tendril (n=3), Medtronic Capsurefix (n=6)] in 21 patients with paroxysmal atrial fibrillation and a normal mean left atrial size of 39 mm (range 33-54 mm). Methods and results Using the Medtronic 2188 lead, successful initial CS canulation and lead positioning was achieved in all 19 patients. One patient developed subclavian vein thrombosis 3 months after initial implant. Eight patients (42%) experienced subsequent lead displacement (12 displacements in total). Of these, seven had their lead replaced with active fixation leads. In addition, two patients underwent active fixation lead implantation at first implant. CS canulation and lead positioning was successful in all nine patients. No patient suffered displacement of an active fixation lead. There were no complications in this group. Twelve of the 19 (66%) Medtronic 2188 leads were functioning at long-term follow-up (11 +/- 4 months) with a biatrial pacing threshold of 2.4 +/- 1 V. Eight of the nine (89%) active fixation leads were functioning at long-term follow-up (6 +/- 3 months) with a biatrial pacing threshold of 2.9 +/- 1.1 V. Using a combined approach 95% of patients had a functioning CS lead at long-term follow-up. Conclusion Active fixation leads can safely be used for left atrial pacing via the CS with good long-term pacing thresholds and stability.

We report our preliminary experience with the combined use of implantable cardioverter defibrillators (ICD) and biventricular pacemakers in six patients with heart failure and malignant ventricular arrhythmia. Two patients underwent ICD implantation for malignant ventricular arrhythmia after previous biventricular pacemaker implantation. One patient underwent biventricular pacemaker insertion for NYHA Class III heart failure after previous ICD implantation. Two patients underwent single device implantation. In the sixth patient, a combined implantation failed due to an inability to obtain a satisfactory left ventricular pacemaker lead position. The potential for device interaction was explored during implantation. In two patients a potentially serious interaction was discovered. Subsequent alterations in device configuration and programming prevented these interactions with long-term use. No complication of combined device use has been demonstrated during a mean follow-up of 2 months (range 1-4 months). Satisfactory ICD and pacemaker function has also been demonstrated. We conclude that combined device implantation may be feasible with currently available pacing technology and that further prospective studies are required in this area.

It has been suggested biatrial pacing may prevent the recurrence of atrial fibrillation (AF). To further evaluate this hypothesis, we performed a randomized, single-blinded study in 19 patients with drug refractory AF. The study compared biatrial pacing with conventional right atrial (RA) pacing and a control period of inhibited pacing. The pacing modes utilized were DDD with a base rate of 70 beats/min for biatrial and RA pace (with and without biatrial resynchronization, respectively) and 40 beats/min for the control period. The duration of each pacing mode was 3 months. The number of AF episodes and their duration were obtained from pacemaker Holter memory (Chorus RM ELA Medical). Comparison of the control period (n = 11) with either pacing strategy showed a significant decrease in the total duration of AF (control 27 +/- 35 days, biatrial 8 +/- 15 days p = 0.02, RA 11 +/- 27 days p = 0.04). However, there was no effect on the number of AF episodes (control 79 +/- 108, biatrial 36 +/- 75 p = 0.32, RA 41 +/- 80 p = 0.11). The total percentage of atrial pacing also significantly increased when the control period (6 +/- 9%) was compared with both RA pace (62 +/- 33%, p = 0.008) and biatrial pace (63 +/- 31, p = 0.003). When biatrial pacing was compared with RA pace (n = 19), there was no significant difference in either the duration of AF (biatrial 16 +/- 26 days vs RA 19 +/- 31 days, p = 0.7) or the number of AF episodes (biatrial 56 +/- 91 vs RA 87 +/- 106, p = 0.34). In conclusion, pacing (either type) at a base rate of 70 beats/min has an antifibrillatory effect when compared with inhibited pacing at 40 beats/min. No additional benefit of biatrial pacing over right atrial pacing was demonstrated in this study.

OBJECTIVE—To review the efficacy of intra-aortic balloon counterpulsation (IABCP) in medically refractory ventricular arrhythmia. DESIGN—Retrospective analysis of the outcome of patients with ventricular arrhythmia treated with IABCP after transfer between 1992 and 1997. SETTING—Tertiary cardiac referral centre. PATIENTS—21 patients (mean age 58 years) who underwent IABCP for control of ventricular arrhythmia. All had significant left ventricular impairment (mean ejection fraction 28.6%); 18 had coronary artery disease. RESULTS—Before IABCP, 10 patients had incessant monomorphic ventricular tachycardia and 11 had paroxysmal ventricular tachycardia and/or ventricular fibrillation (VT/VF). IABCP resulted in suppression of ventricular arrhythmia in 18 patients, of whom 13 were weaned from IABCP. After stabilisation of ventricular arrhythmia, 10 patients were maintained on medical treatment alone and one underwent endocardial resection. IABCP was maintained until cardiac transplantation in five patients. One patient had a fatal arrest before discharge and one died from progressive heart failure. IABCP failed to control ventricular arrhythmia in three patients and was subsequently discontinued. A cardiac assist device was employed in one of these until cardiac transplantation; the other two were eventually stabilised on medical treatment. Nineteen patients were discharged from hospital. Overall survival was 95% at mean follow up of 25.7 months. CONCLUSIONS—IABCP can be an effective means of controlling refractory ventricular arrhythmia, allowing time for the institution of more definitive treatment. Keywords: ventricular arrhythmia; intra-aortic balloon counterpulsation

This report describes the initial results of the "InSync" study, a European and Canadian multicenter trial that examines the safety and efficacy of a multisite pacemaker (Medtronic InSync) and of left ventricular pacing leads (Medtronic 2187 and 2188) implanted via a cardiac vein as a supplemental treatment of refractory congestive heart failure. Over a 10-month period, the system was implanted successfully in 68 of the 81 (84%) patients who had been enrolled in the study. The 68 patients were, on average, 66 +/- 10 years old, had a mean left ventricular ejection fraction (LVEF) = 21% +/- 9%, and 63% were in NYHA functional Class III and 37% were in Class IV. No system implant related complication occurred. During follow-up, 7 of 10 patients who exited the study had died, 4 suddenly. There was a clinical benefit among surviving patients, which was corroborated by a significant improvement in NYHA functional class and in the Minnesota Living with Heart Failure Quality of Life Questionnaire Score (MLS) and by a longer distance covered during a 6-minute walk test. This clinical improvement was associated with a significant narrowing of the paced QRS complex during biventricular pacing, a significant decrease in the interventricular mechanical delay, and a trend towards an increase in the duration of ventricular filling. These encouraging preliminary results confirm the feasibility and reliability of this new multisite pacing system in the management of dilated cardiomyopathy and support the continuation of further evaluations of this complementary treatment of refractory congestive heart failure.

Distributed Denial of Service (DDoS) attacks pose an increasingly grave threat to the Internet, as evidenced by recent DDoS attacks mounted on both popular Internet sites and the Internet infrastructure. Alarmingly, DDoS attacks are observed on a daily basis on most of the large backbone networks. The previous work presented Gaussian distribution factor to enhance the attack resistance scheme for having better detection rate even for stationary object in the application DDoS attacks. The attack detection is identified with the Gaussian distribution of the traffic data of flash crowds surrounding the respective web sites with Bayes optimal filter strategy. But it consumes more time to distribute the Gaussian factor across the Applications used in the network and the security of services in applications also being less. To improve the security and service factor of the network, in this work, we are going to present a polynomial distribution model for attack resistance scheme by distributing the application services prior to sending the packet data streams. The distribution is done at first, so, the service abnormality is identified efficiently. The polynomial distribution is done for organizing the packet data which is to be sent with application services. The simulation using Network Simulator results proves that the attack resistance using polynomial distribution model minimizes execution time, distribution and load overhead and improves the security of the services present in the application contrast to an existing enhanced attack resistance scheme for app-DDoS attacks using Bayes optimal filter strategy.