Catheter ablation of common-type atrial flutter guided by three-dimensional right atrial geometry reconstruction and catheter tracking using cutaneous patches: a randomized prospective study

INTRODUCTION: EnSite NavX (NavX) is a novel mapping and navigation system that allows visualization of conventional catheters for diagnostic and ablative purposes and uses them to create a three-dimensional (3D) geometry of the heart. NavX is particularly suitable for ablation procedures utilizing an anatomic approach, as in the setting of common-type atrial flutter (AFL). The aim of this study was to compare NavX-guided and conventional ablation procedures for AFL. METHODS AND RESULTS: Forty consecutive patients (32 male, 59 +/- 12 years) with documented AFL were randomized to undergo fluoroscopy-guided (group I, 20 patients) or NavX-guided (group II, 20 patients) ablation, including 3D isthmus reconstruction. The same catheter setup was used in both groups. The endpoint of bidirectional isthmus block was obtained in all patients. Compared to conventional approaches, NavX-guided procedures significantly reduced fluoroscopy time (5.1 +/- 1.4 min vs 20 +/- 11 min, P < 0.01) and total x-ray exposure (5.1 +/- 3.1 Gycm2 vs 24.9 +/- 1.6 Gycm2, P < 0.01). Isthmus geometry reconstruction could be performed in all patients of group II. In 4 patients (20%) of group II, anatomic isthmus variations were detected by NavX. No significant differences in radiofrequency current applications and procedural times were found between the two groups. CONCLUSION: NavX technology allows geometry reconstruction of the cavotricuspid isthmus. NavX-guided ablation of AFL reduces total x-ray exposure compared to the fluoroscopy-guided approach but does not prolong procedure time.     

Short‐Term Outcomes of Patent Ductus Arteriosus Closure With New Occlutech® Duct Occluder: A Multicenter Study

Aim

Over the past 2 decades, transcatheter occlusion of patent ductus arteriosus (PDA) with coils and the duct occluders evolved to be the procedure of choice. A new device, the Occlutech PDA® occluder (ODO) device has been designed. Herein, we aimed to evaluate the characteristics and short‐term results of patients who underwent transcatheter closure of PDA using the ODO.

Methods

We reviewed the clinical records of 60 patients from different centers in Turkey between December 2013 and January 2016. The medical records were reviewed for demographic characteristics and echocardiographic findings. Device size was selected on the narrowest diameter of PDA.

Results

The median patient age was 2.5 years (6 months–35 years), and median PDA diameter was 2.5 mm (1.2–11 mm). Fifty‐eight of 60 patients (96.6%) had successful ODO implantation. The occlusion rates were 37/58 (63.7%) at the end of the procedure, 51/58 (87.9%) at 24–48 hours post‐procedure, and 57/58 (98.2%) on echocardiography at a median follow‐up of 7.6 months.

Conclusion

Our results indicate that transcatheter closure of PDA using the ODO is effective. Larger studies and longer follow‐up are required to assess whether its shape and longer length make it superior to other duct occluders in large, tubular, or window‐type ducts. (J Interven Cardiol 2016;29:325–331)

     

Tuberculous peritonitis--reports of 26 cases, detailing diagnostic and therapeutic problems

OBJECTIVE: To evaluate the clinical presentation, biochemical (ascites and serum) and laparoscopic findings, and to assess the efficacy of triple antituberculous therapy without rifampicin for 6 months in patients with tuberculous peritonitis. METHODS: Twenty-six tuberculous peritonitis patients (11 male, 15 female) with a mean age of 34.8 +/- 3.4 years (range 14-77) were assessed with regard to diagnostic and therapeutic features. RESULTS: The most common symptoms and signs were abdominal pain (92.3%) and ascites (96.2%), respectively. Tuberculin skin test (TST) was positive in all patients. An abnormal chest radiography suggestive of previous tuberculosis was present in five patients (19.2%), and two patients (7.7%) had extra-peritoneal (cerebral, pericardial) active tuberculous involvement. In 24 of the 25 patients who underwent laparoscopy with directed biopsy, whitish nodules suggested tuberculous peritonitis; 76% of the biopsy specimens revealed caseating, 20% non-caseating granulomatous inflammation, and 4% non-specific findings. The ascitic fluid of one patient (3.8%) was positive for acid-resistant bacilli, and culture was positive in two patients (7.7%). Twenty-four of the patients were treated for 6 months with isoniazid, streptomycin (total dose 40 g) and pyrazinamide (for the first 2 months and then substituted with ethambutol). Eighteen patients also received methyl prednisolone, initially 20 mg/day, for 1 month. The follow-up period was 19 +/- 1.7 months after the end of therapy (range 6-36). Ascites and abdominal pain abated earlier in patients on steroid therapy. All but two of the 24 patients responded to treatment. CONCLUSION: Non-invasive tests such as acid-fast stain and culture of the ascitic fluid are usually insufficient, hence invasive laparoscopy and peritoneal biopsy are necessary for the diagnosis of tuberculous peritonitis if non-invasive tests such as ascites adenosine deaminase activity measurement are not easily available. Triple therapy without rifampicin for 6 months is sufficient to treat tuberculous peritonitis.     

Cutaneous tuberculosis

Tuberculosis continues to be a significant health problem in developing countries. Although cutaneous tuberculosis is uncommon, disseminating skin involvement may still be seen, especially patients from rural areas. A case is reported of disseminated tuberculosis presenting with different clinical forms of cutaneous lesions, pulmonary and liver involvement in an immunocompetent patient.     

Mathematical model of the rapidly activating delayed rectifier potassium current I(Kr) in rabbit sinoatrial node

INTRODUCTION: A rapidly activating delayed rectifier potassium current (I(Kr)) is known to have an important role in determining the properties of spontaneous pacing in enzymatically isolated rabbit sinoatrial node (SAN) cells. The functional characteristics of I(Kr) are conferred by its dependence on time, voltage, and external potassium. The aim of this study was to develop a rigorous mathematical representation for I(Kr) based on experimental findings and to investigate the role of I(Kr) in the automaticity and intercellular communication of SAN cells. METHODS AND RESULTS: A Markov model was developed using available experimental data for I(Kr) in rabbit SAN. The dependence of I(Kr) on external potassium, [K+]o, was incorporated using data from both in vitro preparations and results from heterologous expression experiments for this ether-a-go-go related gene product. Our simulation results show the following. (1) I(Kr) is the dominant repolarizing current in rabbit SAN cells. (2) Deactivation of I(Kr) contributes to the net current change during the early diastolic depolarization phase. (3) Inward rectification of I(Kr) results in a decrease in membrane resistance during repolarization relative to plateau. (4) The complex [K+]o dependence of I(Kr) confers [K+]o insensitivity on isolated cells, which may account for the sensitivity of pacing rate to elevated [K+]o at the tissue level. CONCLUSION: Model results show that I(Kr) mediates diastolic depolarization by the kinetics of its decay and by lowering resistance during late repolarization. In elevated [K+]o, increased chord conductance is balanced by the changes in kinetics and voltage dependence of I(Kr) so that the pacing rate of single cells may be more [K+]o insensitive than expected. In addition, elevated [K+]o increases I(Kr) magnitude during repolarization but lowers resistance, so current flow through gap junctions is less able to hyperpolarize pacing cells.     

One-year follow up results of Smoking Cessation Outpatient Clinic

In this study we investigated the five-year-results of our smoking cessation outpatient clinic retrospectively. Out of 839 subjects admitted to our clinic during this time period 634 of them completed the one-year follow up period. 318 (50.2%) of these subjects were male and 316 (49.8%) of them were female. Subjects were divided into two groups. While one group received nicotine patch therapy, education and motivation the other group received just education and motivation. Mean age was 43.5 +/- 12 years. Nicotine patch therapy administered to 297 subjects and smoking cessation rates in this group were 46.8% at 15th day and 33.6% at the end of first year. The other group had smoking cessation rates of 11.8% at 15th day and 10.9% at the end of one year. Out of 185 subjects who did not smoke at the end of 15th day 98 of them were also not smoking at the end of one year. 449 subjects were smoking at the end of 15th day and just 26 (5.7%) of them gave up smoking at the end of first year. Therapy compliance was 82.2% at the 15th day and 23.2% at 12th week. Most frequent side effects were local skin reactions (13.8%) due to nicotine patches, irritability and nervousness (8.5%) and concentration difficulties (7.4%). In this retrospective analysis we concluded that nicotine replacement therapy in conjunction with education and motivation may be an effective method for helping individuals in giving up smoking. We also observed that smoking situation in first 15 days is a good predictor of long-term success.     

From vulnerable plaque to vulnerable patient: a call for new definitions and risk assessment strategies: Part II

Atherosclerotic cardiovascular disease results in >19 million deaths annually, and coronary heart disease accounts for the majority of this toll. Despite major advances in treatment of coronary heart disease patients, a large number of victims of the disease who are apparently healthy die suddenly without prior symptoms. Available screening and diagnostic methods are insufficient to identify the victims before the event occurs. The recognition of the role of the vulnerable plaque has opened new avenues of opportunity in the field of cardiovascular medicine. This consensus document concludes the following. (1) Rupture-prone plaques are not the only vulnerable plaques. All types of atherosclerotic plaques with high likelihood of thrombotic complications and rapid progression should be considered as vulnerable plaques. We propose a classification for clinical as well as pathological evaluation of vulnerable plaques. (2) Vulnerable plaques are not the only culprit factors for the development of acute coronary syndromes, myocardial infarction, and sudden cardiac death. Vulnerable blood (prone to thrombosis) and vulnerable myocardium (prone to fatal arrhythmia) play an important role in the outcome. Therefore, the term "vulnerable patient" may be more appropriate and is proposed now for the identification of subjects with high likelihood of developing cardiac events in the near future. (3) A quantitative method for cumulative risk assessment of vulnerable patients needs to be developed that may include variables based on plaque, blood, and myocardial vulnerability. In Part I of this consensus document, we cover the new definition of vulnerable plaque and its relationship with vulnerable patients. Part II of this consensus document will focus on vulnerable blood and vulnerable myocardium and provide an outline of overall risk assessment of vulnerable patients. Parts I and II are meant to provide a general consensus and overviews the new field of vulnerable patient. Recently developed assays (eg, C-reactive protein), imaging techniques (eg, CT and MRI), noninvasive electrophysiological tests (for vulnerable myocardium), and emerging catheters (to localize and characterize vulnerable plaque) in combination with future genomic and proteomic techniques will guide us in the search for vulnerable patients. It will also lead to the development and deployment of new therapies and ultimately to reduce the incidence of acute coronary syndromes and sudden cardiac death. We encourage healthcare policy makers to promote translational research for screening and treatment of vulnerable patients.     

Technical and clinical evaluation of a glucose meter employing amperometric biosensor technology

The objective of this study was to assess accuracy and precision of the Optimum H System for measuring glucose in fresh venous whole blood samples. Ninety-one whole blood specimens were analyzed duplicate on two optimum blood glucose meter and compared to YSI reference analyser and Beckman LX20 laboratory analyser. The study demonstrated that the Optimum H System gives clinically accurate, plasma equivalent glucose results for venous samples, compared to the YSI*1.12 reference method. All results were within the clinically acceptable A and B zones of the Parkes error grid, with 98.6% falling within zone A. The mean bias of the Optimum H System versus the YSI*1.12 reference was +5.39%, which is consistent with the strip claim that slightly higher results may be observed when using venous samples. The Optimum H System results showed good precision, with an overall mean CV of 3.0%. Plasma results from the Beckman laboratory analyser correlated well with the YSI*1.12 whole blood reference with a slightly higher mean bias of +3.92%. The study demonstrated the Optimum H System to give clinically accurate and precise results for glucose in fresh venous whole blood samples.