Guidewire pacing during transcatheter aortic valve implantation in a patient with complex congenital heart disease

We present a case of temporary guidewire pacing in a patient with Fontan anatomy during transcatheter aortic valve implantation. Temporary pacing was successfully achieved utilizing this method without complications. There is an increasing population of patients with complex congenital heart disease and expanding variety of transcatheter interventions. Due to limitations in vascular access and surgical anatomies, guidewire pacing may have a wide array of potential applications in pediatrics and the congenital heart disease population.     

Doppler echocardiographic evaluation of pulmonary artery flow after modified Fontan operation: importance of atrial contraction

Doppler echocardiography was used to evaluate blood flow in the pulmonary artery in 14 patients 2 to 42 months (mean (SD) 17 (12) months) after a modified Fontan operation incorporating a direct atriopulmonary anastomosis. Preoperatively six patients had tricuspid atresia, six had a double inlet left ventricle, and two had pulmonary atresia with an intact ventricular septum. The postoperative rhythm was sinus in 11 patients, junctional in one, ventricular pacing in one, and atrioventricular sequential pacing in one. In one patient the Doppler trace was unsatisfactory for analysis. In all patients forward flow in the pulmonary artery had biphasic peaks related to both atrial and ventricular contraction. The mean (SD) peak flow velocity that was synchronous with atrial contraction was 80 (30) cm/s and that synchronous with ventricular contraction was 74 (23) cm/s. The atrial contribution to total pulmonary artery flow, assessed by velocity-time integrals, varied between 22% and 73% (mean (SD) 45 (14)%). In patients with tricuspid atresia the mean (SD) peak flow velocity with atrial contraction was 90 (27) cm/s and that with ventricular contraction was mean (SD) 68 (24) cm/s. In patients with double inlet left ventricle the mean (SD) peak flow velocity was 67 (36) cm/s with atrial contraction and 80 (25) cm/s with ventricular contraction. The atrial contribution to total pulmonary blood flow in patients with tricuspid atresia was significantly higher (53 (11)%) than in those with double inlet left ventricle (37 (14)%). Pulmonary artery flow after modified Fontan operation was biphasic and was related to both atrial and ventricular contraction. The atrial contribution to pulmonary blood flow is greater in patients with tricuspid atresia than in those with a double inlet left ventricle. The mechanism of the second peak related to ventricular contraction is unknown.     

Noncirrhotic portal fibrosis/idiopathic portal hypertension: APASL recommendations for diagnosis and treatment

The Asian Pacific Association for the Study of the Liver (APASL) Working Party on Portal Hypertension has developed consensus guidelines on the disease profile, diagnosis, and management of noncirrhotic portal fibrosis and idiopathic portal hypertension. The consensus statements, prepared and deliberated at length by the experts in this field, were presented at the annual meeting of the APASL at Kyoto in March 2007. This article includes the statements approved by the APASL along with brief backgrounds of various aspects of the disease.     

Pulmonary regurgitation in transposition of the great arteries.

A female infant who presented with cyanosis and tachypnoea was found to have transposition of the great arteries, a ductus arteriosus, and a ventricular septal defect. An aortogram showed evidence of mild pulmonary regurgitation, which persisted after a Senning's operation; this is a hitherto unrecognised clinical finding.     

Variation management by functional tolerance allocation and manufacturing process selection

The imperfections of the manufacturing process lead to functional characteristics degradation, and therefore product quality. To ensure a certain level of product quality, the synthesis of tolerance (tolerance design) aims to determine the acceptable limits of the characteristics of parts, assemblies... The allocation or synthesis of functional tolerances is an important step in the design process which takes place generally during the detailed design and greatly impacts the design of the manufacturing process, manufacturing and product control. That is why it is important, when functional tolerances are quantified, to take into account their impacts on the manufacturing cost and product quality. These two concepts (manufacturing cost and product quality) are usually considered as conflicting goals. The proposed approach aims to allocate the functional tolerances that provide the best ratio between functional performances and manufacturing cost. It is based on the “Key Characteristics” approach, developed by Boeing coupled with an activities approach. This optimization is carried out by a genetic algorithm. The process selection is performed by a constraint satisfaction algorithm. Finally, the impacts of process choices are assessed with the Monte Carlo simulation which calculates the behavior and quality of the resulting product.     

Epigenetic Mechanisms Underlying the Pathogenesis of Neurogenetic Diseases

There have been considerable advances in uncovering the complex genetic mechanisms that underlie nervous system disease pathogenesis, particularly with the advent of exome and whole genome sequencing techniques. The emerging field of epigenetics is also providing further insights into these mechanisms. Here, we discuss our understanding of the interplay that exists between genetic and epigenetic mechanisms in these disorders, highlighting the nascent field of epigenetic epidemiology—which focuses on analyzing relationships between the epigenome and environmental exposures, development and aging, other health-related phenotypes, and disease states—and next-generation research tools (i.e., those leveraging synthetic and chemical biology and optogenetics) for examining precisely how epigenetic modifications at specific genomic sites affect disease processes.     

High Risk of New Episode of Symptomatic Vasospasm in Unaffected Arteries in Subarachnoid Hemorrhage Patients Receiving Targeted Endovascular Treatment for Symptomatic Focal Vasospasm

Background

There is controversy whether asymptomatic vasospasm in other arteries should be concurrently treated (global treatment) in patients receiving targeted endovascular treatment [percutaneous-transluminal-angioplasty (PTA) and/or intra-arterial (IA) vasodilators] for focal symptomatic vasospasm.

Objective

To determine the rates of occurrence of new symptomatic vasospasm in previously asymptomatic arterial distributions among patients with aneurysmal subarachnoid hemorrhage (SAH) who underwent targeted endovascular treatment for focal symptomatic vasospasm.

Methods

We identified all patients with SAH who had received targeted endovascular treatment during a 4-year period. We ascertained any new occurrence of symptomatic vasosopasm requiring endovascular treatment in previously unaffected (and untreated) arterial distributions within the same hospitalization. Blinded reviewers quantitatively graded angiographic vasospasm (<25, 26–49, ≥50 %) in all major arteries for each patient at the time of targeted treatment.

Results

Of the 41 patients who received targeted endovascular treatment (PTA in 41 % and vasodilators in 59 %), 11 (27 %) developed new symptomatic vasospasm in previously asymptomatic vascular distributions requiring endovascular treatment. Moderate severity of angiographic vasospasm in asymptomatic arteries at the time of targeted treatment tended to predict the occurrence of new symptomatic vasospasm. The rate of death and disability at discharge [modified Rankin scale (mRS) of 3–6] was 82 % (9/11) among those who developed a new episode of symptomatic vasospasm compared with 70 % (21/30) in those who did not (P = 0.58).

Conclusions

High risk of new occurrence of ischemic symptoms in previously asymptomatic (and untreated) arterial distributions among patients receiving targeted treatment should be recognized. Further studies should evaluate the benefit of performing global endovascular treatment during the initial targeted endovascular treatment session.     

Predictors of poor outcome of decompressive craniectomy in pediatric patients with severe traumatic brain injury: a retrospective single center study from Pakistan

Objective

This study aimed to determine the risk factors associated with poor outcome of decompressive craniectomy (DC) for severe traumatic brain injury (TBI) in pediatric patients.

Methods

This retrospective study is conducted on pediatric population (age 1–15 years) presenting with TBI who underwent DC at our institute between January 2000 and 2010. Based on Glasgow outcome score (GOS) at a minimum follow-up of 5 months, patients were divided into two groups, namely poor outcome (GOS 1, 2, and 3) and good outcome (GOS 4 and 5). Records were reviewed and analyzed for preoperative and intraoperative predictors.

Results

We found 25 patients who were eligible as per selection criteria. Mean age at presentation was 6?±?4 years and there was male preponderance (84 %). Fall (60 %) was the most common mechanism of injury followed by gunshots and road traffic accident. On univariate analysis, presenting GCS ≤5 (p value?=?0.009), delay in presentation of more than 150 min (p value?=?0.010), DC performed after more than 4 h of arrival in hospital (p value?=?0.042), and intraoperative blood loss exceeding 300 ml (p value?=?0.001) were significant predictors of poor outcome.

Conclusion

Our study suggests that DC in children is not only a life-saving procedure, but also leads to a good functional outcome after severe injury. However, patient selection still remains an important aspect, and the above-mentioned factors should be considered while deciding for DC to improve survival. Further prospective studies on larger sample size are warranted to validate our results.     

A systematic review and meta-analysis evaluating the role of laparoscopic surgical resection of transverse colon tumours

Objectives

A meta-analysis of published literature comparing outcomes after laparoscopic resection (LR) with open resection (OR) for transverse colon tumours.

Methods

Medline, PubMed, CINAHL, EMBASE and Cochrane were searched from inception to October 2013. The text words “minimally invasive”, “keyhole surgery” and “transverse colon” were used in combination with the medical subject headings “laparoscopy” and “colon cancer”. Outcome variables were chosen based upon whether the included articles reported results. A meta-analysis was performed to obtain a summative outcome.

Results

Six comparatives involving 444 patients were analysed. Of them 245 patients were in the LR group and 199 in the OR group. There was a significant increase in operative time in the LR group compared with the OR group [random effects model: SMD = ?0.65, 95 % CI (?1.01, ?0.30), z = ?3.60, p < 0.001] but there was significant heterogeneity amongst trials (Q = 15.51, df = 5, p = 0.008, I ² = 68). There was less blood loss in the LR group [fixed effects model: SMD = 0.70, 95 % CI (0.47, 0.93), z = 6.01, p < 0.001] and patients returned to oral diet earlier [random effects model: SMD = 0.78, 95 % CI (0.40, 1.16), z = 4.01, p < 0.001] and had a reduced time to functioning bowel [fixed effects model: SMD = 0.86, 95 % CI (0.60, 1.11), z = 6.63, p < 0.001]. No difference was seen for overall morbidity (p = 0.76) or mortality (p = 0.58).

Conclusions

LR of transverse colon tumours is a safe and effective technique. Although there is an increase in operating time, operative and clinical outcomes of intraoperative blood loss and faster recovery are seen with laparoscopic procedures.