Pattern of initiation of monomorphic ventricular tachycardia in recorded intracardiac electrograms

Background: By analyzing stored intracardiac electrograms during spontaneous monomorphic ventricular tachycardia (VT), we examined the patterns of the VT initiation in a group of patients with implantable cardioverter defibrillators (ICDs). Methods: Stored electrograms (EGMs) were monomorphic VTs and at least 5 beats before the initiation and after the termination of VT were analyzed. Cycle length, sinus rate, and the prematurity index for each episode were noted. Results: We studied 182 episodes of VT among 50 patients with ICDs. VPC-induced (extrasystolic initiation) episode was the most frequent pattern (106; 58%) followed by 76 episodes (42%) in sudden-onset group. Among the VPC-induced group, VPCs in 85 episodes (80%) were different in morphology from subsequent VT. Sudden-onset episodes had longer cycle lengths (377±30ms) in comparison with the VPC-induced ones (349±29ms; P= 0.001). Sinus rate before VT was faster in the sudden-onset compared to that in VPC-induced one (599±227ms versus 664±213ms; P=0.005). Both of these episodes responded similarly to ICD tiered therapy. There was no statistically significant difference in coupling interval, prematurity index, underlying heart disease, ejection fraction, and antiarrhythmic drug usage between two groups (P=NS). Conclusions: Dissimilarities between VT initiation patterns could not be explained by differences in electrical (coupling interval, and prematurity index) or clinical (heart disease, ejection fraction, and antiarrhythmic drug) variables among the patients. There is no association between pattern of VT initiation and the success rate of electrical therapy

Analisis Penurunan Peserta Jaminan Pemeliharaan Kesehatan Masyarakat (Jpkm) Bapel Sintesa Kendari = Analysis Of The Declining Number Of Community Health Care Insurance Participant Of

Background: Service agency of Sintesa Community Health Care Insurance Kendari was founded as community health insurance agency at Kendari City. At the begining the agency attracts people to become participants of health care insurance but due to some reasons the number of participants decline. Objective: The study was aims to identify factors leading to opting out and continuation as member of community health care insurance agency. Methods: The study was a qualitative and quantitative type. The qualitative method was applied to 3 groups (22 people) of focus group discussion, two groups of which consisted of those who opted out from their participation and one group consisted of those who continued their participation in the insurance, followed by indepth interview with 4 respondents who opted out and 2 respondents who were active participants the topics for study are premium issues, perception of being ill, health care packages, health services at health centers and the professionalism of service agency. The discussion and interview were recorded, transcripts were compiled and open coding was conducted. Results: Most respondents, both who resigned and were active participants, worried about the cost of being ill. Most participants who resigned said that premi was too high and that they were dissatisfied with health care packages. Most participants, either those who opted out or those who were still active said that health service at health centers was unsatisfactory and the professionalism of service agency was low. Active participants had more knowledge about community health care insurance than those who resigned. Factors leading to decision of opting out from participation were the absence of premi collector, temporary cancellation of premi collection, unawareness of the functioning of community health care insurance, and distrust toward service agency. Factors leading to active participation were benefits of having the insurance when participants were ill, satisfaction with health care packages and the fact that participants had no other health insurance. Conclusion: High premi, unsatisfactory health service at health centers and health care packages, as well as low professionalism of service agency were factors leading to decision of opting out from the insurance. Consequently there was declining number of community health care insurance participants at Sintesa service agency. Keywords: community health care insurance, resigned an active participan

Idiopathic Submitral Left Ventricular Aneurysm: an Unusual Substrate for Ventricular Tachycardia in Caucasians

Annular submitral aneurysms have been rarely reported in Caucasians. They are typically diagnosed in non-white adults who present with severe mitral regurgitation, heart failure, systemic embolism, ventricular arrhythmias, and sudden cardiac death. In this article, we describe the case of a white woman, presenting with ventricular tachycardia, who had a large submitral left ventricular aneurysm diagnosed incidentally during coronary angiography

Changing QRS Morphology: What is the mechanism?

ECG in sinus rhythm with ventricular preexcitation and changing QRS morphology was seen that was initially interpreted as the multiple accessory pathway from elsewhere. (Figure 1A). The following mechanisms are potentially involved in the electrogenesis of changing QRS morphology in WPW syndrome: 1) multiple accessory pathways1; 2) simultaneous occurrence of aberrant atrioventricular conduction with accessory pathway conduction 2; 3) ventricular fusion of preexcited sinus impulse with ectopic impulse. Electrophysiologic study showed short PR (75 ms) interval with wide QRS (152 ms) and negative HV (-12 ms) interval. No change in delta wave polarity was observed during HRA and CS pacing. In full preexcitation, no breakthrough was seen in the CS. During incremental ventricular pacing, atrial breakthrough site is initially recorded on the HRA catheter and then changed to distal pole of CS catheter with progressive decrease in pacing cycle length. During ventricular pacing at cycle length of 500 ms (S1), earliest atrial activity is recorded on HRA catheter. Changing QRS could not be explained by presence of multiple APs because only right-sided AP had bidirectional conduction and no distal CS breakthrough was seen simultaneous with changing QRS morphology. The possibility of aberrant conduction is excluded by presence of negative HV interval in the beats with differing QRS morphology. No sinus cycle length variation before and after the beats with different morphologies are against the occurrence of functional LBBB. The prematurity of ventricular electrogram in His recording catheter with variable HV (H-electrogram is recorded after V-electrogram in second beat and before V-electrogram in third beat) and fixed V-RB intervals (interval from ventricular electrogram in His to the RB potential) are compatible with ventricular fusion of preexcited sinus impulse with ectopic ventricular impulse originating from parahissian area (explaining LBBB and inferior axis morphology of the beats with changing QRS) but not from the His bundle or RBB itself (because H-electrogram and RB potential is recorded after V-electrogram in the second beat with greater degree of ventricular fusion)(Figure 1B)

Radiofrequency Catheter Ablation of Atrioventricular Nodal Reentrant Tachycardia: It Is Not Always As It Is Expected

Observation of Coincident arrhythmias is not uncommon but the co-existence of idiopathic verapamil sensitive left ventricular tachycardia (ILVT) with other arrhythmias is very rare. We hereby presented a 30 year old male patient with a history of frequent episodes of palpitations and sustained narrow complex tachycardia. During electrophysiologic study two arrhythmias, one with narrow complexes which was shown to be typical atrioventricular nodal re-entrant tachycardia and the other with wide QRS complexes and right bundle branch block and left axis morphology, compatible with ILVT, were inducible. Radiofrequency catheter ablation of both arrhythmias was done at two consecutive sessions. The patient has remained asymptomatic without antiarrhythmic therapy for the past six months

Investigating biomarkers in Parkinson's disease using machine learning

Genome-Wide Association Studies (GWAS) identify genetic variations in individuals affected with diseases such as Parkinson's disease (PD), whose allele or genotype frequencies are significantly different between the affected individuals and individuals who are free of the disease. GWAS data can be used to identify genetic variations associated with the disease of interest. However, GWAS datasets are extensive and contain many more Single Nucleotide Polymorphisms (SNPs pronounced “snips”) than individual samples. To address these challenges, we used Singular-Vectors Feature Selection (SVFS) and applied it to PD GWAS datasets. We discovered a group of SNPs that are potentially novel PD biomarkers as we found indirect links between them and PD in the literature but have not directly been associated with PD before. Direct association means that current literature directly links a SNP with PD; while an indirect link means that current literature suggests the involvement of a SNP in a disease other than PD but this other disease co-occurs with PD in a significant number of PD patients. These indirectly-linked SNPs open new potential lines of investigation. Directly-linked SNPs identified by our method are rs11248060, rs239748, rs999473, and rs2313982. One can see the full list of identified SNPs in Section 4.4

Semi-analytical methods for simulating the groundwater-surface water interface

Groundwater-surface water interaction is a key component of the hydrologic cycle. This interaction plays a key role in many environmental issues such as the impacts of land use and climate change on water availability and water quality. Modeling of local and regional groundwater-surface water interactions improves understanding of these environmental issues and assists in addressing them. Because of the physical and mathematical complexities of this interaction, numerical approaches are generally used to model water exchange between subsurface and surface domains. The efficiency, accuracy, and stability of mesh-based numerical models, however, depend upon the resolution of the underlying grid or mesh. Grid-free analytical methods can provide fast, accurate, continuous and differentiable solutions to groundwater-surface water interaction problems. These solutions exactly satisfy mass balance in the entire internal domain and may improve our understanding of groundwater-surface water interaction principles. However, to model this interaction, analytical approaches typically required simplifying, sometimes unrealistic, assumptions. They are typically used to implement linearized mathematical models in homogenous confined or semi-confined aquifers with geometrically regular domains. By benefiting from the strengths of both analytical and numerical approaches, grid-free semi-analytical methods may be able to address more challenging groundwater problems which have been out of reach of traditional analytical approaches, and/or are poorly simulated using mesh-based numerical methods. Here, novel 2-D and 3-D semi-analytical solutions for the simulation of mathematically and physically complex groundwater-surface water interaction problems are developed, assessed and applied. Those models are based upon the series solution method and analytic element method (AEM) and are intended to address groundwater-surface water interactions induced by pumping wells and/or the presence of surface water bodies in naturally complex stratified unconfined aquifers. Semi-analytical solutions are obtained using the least squares method, which is used to determine the unknown coefficients in the series expansion and the unknown strengths of analytic elements. The series and AEM solutions automatically satisfy the groundwater governing equation. Hence, the resulting solutions are exact over the entire domain except along boundaries and layer interfaces where boundary and continuity conditions are met with high precision. A robust iterative algorithm is used to implement a free boundary condition along the phreatic surface with a priori unknown location. This thesis addresses three general problem types never addressed within a semi-analytic framework. First, a steady-state free boundary semi-analytical series solutions model is developed to simulate 2-D saturated-unsaturated flow in geometrically complex stratified unconfined aquifers. The saturated-unsaturated flow is controlled by water exchange along the land surface (e.g., evapotranspiration and infiltration) and the presence of surface water bodies. The water table and capillary fringe are allowed to intersect stratigraphic interfaces. The capillary fringe zone, unsaturated zone, groundwater zone and their interactions are incorporated with a high degree of accuracy. This model is used to assess the influences of important factors on unsaturated flow behavior and the water table elevation. Second, a 3-D free boundary semi-analytical series solution model is developed to simulate groundwater-surface water interaction controlled by infiltration, seepage faces and surface water bodies along the land surface. This model can simulate the water exchange between groundwater and surface water in geometrically complex stratified phreatic (unconfined) aquifers. The a priori unknown phreatic surface will be obtained iteratively while the locations of seepage faces don’t have to be known a priori (i.e., this is a constrained free boundary problem). This accurate grid-free multi-layer model is here used to investigate the impact of the sediment layer geometry and properties on lake-aquifer interaction. Using this method, the efficiency of widely-used Dupuit-Forchheimer approximation used in regional groundwater-surface water interaction models is also assessed. Lastly, this 3-D groundwater-surface water interaction model is augmented with AEM solutions to simulate horizontal pumping wells (radial collector well) for assessing surface water impacted by pumping and determining the source of extracted well water. The resulting model will be used to assess controlling parameters on the design of a radial collector well in a river bank filtration system. This 3-D Series-AEM model, in addition, mitigates the limitations of AEM in modeling of general 3-D groundwater-surface water interaction problems

Brugada Syndrome Manifested by the Typical Electrocardiographic Pattern both in the Right Precordial and the High Lateral Leads

We identified a patient with the Brugada syndrome and frequent episodes of the traumatic syncope. This patient presented with alternating ST-segment elevation in the right precordial and the high lateral leads. The signal-averaged ECG was positive for the late potentials and electrophysiology study revealed no inducible supraventricular or ventricular tachycardias. Because of the frequent traumatic syncope, a dual-chamber implantable cardioverter-defibrillator was implanted. This report suggests that the Brugada syndrome may have different electrocardiographic presentations within a single individual over a short period of time. The significance of these changes needs to be assessed in a prospective long term study

Idiopathic Submitral Left Ventricular Aneurysm: an unusual substrate for ventricular tachycardia in Caucasians

Annular submitral aneurysms have been rarely reported in Caucasians. They are typically diagnosed in non-white adults who present with severe mitral regurgitation, heart failure, systemic embolism, ventricular arrhythmias, and sudden cardiac death. In this article, we describe the case of a white woman, presenting with ventricular tachycardia, who had a large submitral left ventricular aneurysm diagnosed incidentally during coronary angiography

Concealed Malfunction of The Temporary Pacemaker

The 12-lead ECG shows sequential atrial and ventricular pacing (Figure 1A). A tracing, obtained simultaneously during pacemaker interrogation, disclosed pacemaker functioning as VDD mode (Figure 1B). The careful examination of this pacemaker tracing showed that there is a pacing stimulus before each P wave (compatible with DDD mode). This paradox can only be explained by displacement of the temporary pacing lead to right atrium and right atrial stimulation by temporary pacemaker. In this setting, each temporary pacemaker-induced atrial depolarization is tracked by the right atrial lead of the permanent pacemaker as intrinsic P wave. Fluoroscopic study confirmed this explanation (Figure 2). The displaced temporary pacing lead was seen near the lateral right atrial wall. Temporary pacemaker lead had been inserted before replacement of permanent pacemaker