Safety and Effectiveness of Transvenous Lead Extraction in Octogenarians

Transvenous Lead Extraction . Introduction: As the population ages, the number of elderly patients with implantable cardiac devices referred for transvenous lead extraction will dramatically increase in Western countries. The safety and effectiveness of lead extraction in elderly patients has not been well evaluated. We report the safety and effectiveness of transvenous lead extraction in octogenarians. Methods and Results: From January 2005 to January 2011, we reviewed data from consecutive patients ≥ 80 years referred to our institutions for transvenous lead extraction because of cardiac device infection or lead malfunction. Clinical characteristics, procedural features, and periprocedural major and minor complications were compared between octogenarians and younger patients. Out of 849 patients undergoing lead extraction in the participating institutions during the study period, 150 (18%) patients were octogenarians (mean age 84 years; range 80–96; 64% males). A significantly higher percentage of octogenarians presented with chronic renal failure (55% vs 26%; P < 0.001), history of malignancy (22% vs 6%; P < 0.001), and chronic obstructive pulmonary disease (46% vs 19%; P < 0.001). Complete lead extraction rates were similar in the 2 age groups (97% in octogenarians vs 96% in patients <80 years; P = 0.39). Periprocedural death occurred in 2 (1.3%) patients ≥80 years and in 5 (0.72%) patients <80 years (P = 0.45 for comparison). No differences in terms of other periprocedural major and minor complications were found between the 2 age groups. Conclusion: Despite presenting with a significantly higher rate of comorbidities, transvenous lead extraction can be performed safely and successfully in octogenarians. (J Cardiovasc Electrophysiol, Vol. 23 pp. 1103‐1108, October 2012)     

The Short-Term Effect on Restenosis and Thrombosis of a Cobalt-Chromium Stent Eluting Two Drugs in a Porcine Coronary Artery Model

The aim of this article was to study the effect of dual drug-eluting stent (DES) on both restenosis and thrombosis in a porcine coronary artery model. This study reports on the use of two drugs coated on the stent to simultaneously minimize both restenosis and thrombosis. The DES was prepared by spray coating a bare metal stent with a biodegradable polymer loaded with sirolimus and triflusal, to treat against restenosis and thrombosis, respectively. The two-layered dual drug-coated stent was characterized in vitro for surface properties before and after expansion, as well as for possible delamination by cross-sectioning the stent in vitro. In vivo animal studies (in a pig model) were then performed for acute thrombosis, inflammation, and restenosis. The results show a significant reduction in restenosis with a stent coated with both drugs compared with the controls (a bare metal stent, a sirolimus-coated, and a pure polymer-coated stent). The reduction in restenosis with a sirolimus/triflusal-eluting stent is associated with an inhibition of inflammation and thrombus formation, suggesting that such dual DES have a role to play for the treatment of coronary artery diseases.     

An interplay of alleviating mutations in the clinical phenotype of β‐thalassaemia intermedia

Prediction of a β‐thalassaemia major phenotype from the β‐genotype is generally relatively straightforward. However, despite the ability to accurately define the β‐thalassaemia mutations, prediction of a β‐thalassaemia intermedia phenotype from the genotype sometimes remains problematic and this has important implications in genetic counselling and prenatal diagnosis. We report a 11‐year‐old Indian male child with a thalassaemia intermedia phenotype. β‐Globin gene analysis of the family showed that he was a compound heterozygote with the ?88 (C→T) β⁺‐mutation and the IVS1 nt 130 (G→C) β⁰‐mutation. Both these mutations are rare among Indians. The propositus was also found to be heterozygous for the XmnI polymorphism and had a normal α‐genotype. In this family interplay of two alleviating mutations (a milder promoter mutation along with a gene for raised HbF) might have synergistically compensated for lack of globin chains in the patient. Hence, the nature of the β‐genotype as well as the knowledge of the presence or absence of alleviating factors will help the clinician to decide whether early commencement of a regular transfusion regime is necessary.     

Variant rs2200733 on Chromosome 4q25 Confers Increased Risk of Atrial Fibrillation: Evidence From a Meta‐Analysis

Variant rs2200733 on Chromosome 4q25 Confers Increased Risk . Introduction: Several genome‐wide association studies have identified rs2200733, a single‐nucleotide polymorphism (SNP) at 4q25 to be the most common chromosomal variant present in patients with atrial fibrillation (AF). We aimed to explore the association of rs2200733 with AF through a systematic review and meta‐analysis. Method: An extensive literature search was performed on PubMed, and other databases using the key words “genetics” and “AF.” Seven case‐control studies evaluating the association via multivariate analysis were identified including a total of 83,335 subjects (10,546 with AF, 72,789 referent individuals without AF). Meta‐analytic estimates were derived using random effects models. Potential sources of heterogeneity were examined in sensitivity analyses, and publication biases were estimated. Result: At pooled analysis, there was a strong independent association between the variant rs2200733 and the risk of AF (OR 1.89 [95% CI 1.62–2.16], P < 0.001). Minor allelic frequencies for SNP rs22000733 were significantly more prevalent in AF population than non‐AF. Metaregression results revealed that country of descent (logOR 0.38, P = 0.45) or site of study (logOR: ?0.16, P = 0.41) did not moderate the overall effect size. Conclusion: Variant rs2200733 on chromosome 4q25 independently confers increased risk of AF. This finding will aid in improving our understanding of AF pathophysiology, risk prediction, and stratification of treatment strategy. (J Cardiovasc Electrophysiol, Vol. 24, pp. 155‐161, February 2013)     

Hydroxyl radical formation in human gastric juice

The hydroxyl radical is the most potent free radical derived from oxygen, and has been implicated in damage caused to the gastroduodenal mucosa. The ability of human gastric juice to generate hydroxyl radicals has been investigated in 54 adults with endoscopically normal gastroduodenal mucosa and in 39 patients with chronic duodenal ulcer. Hydroxyl radical production was measured by the formation of formaldehyde from dimethylsulfoxide. Unlike other body fluids, this reaction could proceed without the extraneous addition of catalysts such as hydrogen peroxide (H2O2), ascorbate and iron. Measurement of H2O2, iron and ascorbate showed that these catalysts are already present in the gastric juice. There was no significant difference in the concentration of these components in gastric juice between normal subjects and patients with duodenal ulcer, except that H2O2 levels were slightly higher in duodenal ulcer patients. Although generation of free radicals has been investigated in other body fluids, this is the first reported case regarding the production of these active species in normal human gastric juice. Since hydroxyl production is not significantly enhanced in duodenal ulcer, we suggest that attention may be turned to mucosal antioxidant defences in this disease.     

Long‐Term Functional and Neurocognitive Recovery in Patients Who Had an Acute Cerebrovascular Event Secondary to Catheter Ablation for Atrial Fibrillation

PVAI and Stroke . Introduction: Cerebral thromboembolic event (CTE) is a possible complication of pulmonary vein antrum isolation (PVAI). The objective of this study was to report long‐term functional and neurocognitive recovery in patients who had a CTE during or within 48 hours of catheter ablation. Methods and Results: We screened 3,060 patients who underwent PVAI between January 2000 and June 2007. Out the 3,060 patients, 26 patients (0.8%) (61 ± 8 years, 88% males) had a CTE during or within 48 hours of the procedure. We followed these 26 patients (study group) over time and assessed their functional and neurocognitive recovery status. No preferential vascular territory for the site of obstruction was found; right anterior circulation‐5 patients (26%), left anterior circulation‐5 patients (26%), posterior circulation‐3 patients (16%), and 2 or more territories‐6 patients (32%), (P‐value = 0.8). The average international normalized ratio at the time of CTE was 1.33 ± 0.4. Two patients died during the study period. At the end of 38.4 ± 24 months follow‐up, most surviving patients had complete neurocognitive and functional recovery irrespective of the severity of periprocedural stroke. Conclusions: Periprocedural stroke in the setting of catheter ablation for atrial fibrillation is relatively rare. When it occurs, complete functional and neurocognitive recovery over time is the likely outcome for most patients. (J Cardiovasc Electrophysiol, Vol. 21, pp. 412–417, April 2010)