Isolation of the phrenic nerve to suppress diaphragmatic contraction induced by cardiac resynchronization

Left phrenic nerve stimulation is a well-known complication of cardiac resynchronization therapy (CRT). We report a case where electronic or anatomical repositioning of the left ventricular (LV) electrode (within the coronary sinus tributaries) was not feasible/effective. Surgical graft interpositioning was performed to successfully isolate the phrenic nerve from the previously implanted coronary sinus epicardial LV lead.     

Triaging in pulmonary embolism

Risk stratification of patients with pulmonary embolism represents an important step and may help to guide initial therapeutic management. Pulmonary embolism can be stratified into several groups, with different risk of early death or complications based on the presence of several risk factors. High-risk pulmonary embolism is defined by shock or peripheral signs of hypoperfusion. It is a life-threatening emergency with high short-term mortality (>25%) requiring specific therapeutic strategy with inotropic agents and fibrinolysis. In normotensive patients with pulmonary embolism, the presence of right ventricular dysfunction assessed by echocardiography or myocardial injury based on elevated levels of biomarkers, is associated with an intermediate risk of early death. These patients require close monitoring, and the role of thrombolytic treatment is currently assessed in a large trial. Lastly, patients with normotensive pulmonary embolism and without right ventricular dysfunction or myocardial injury have a low risk of death and complications. These patients may be candidates for home treatment. Several scores combining these risk factors have been described.     

Variation in PTX3 Is Associated with Primary Graft Dysfunction after Lung Transplantation

Rationale: Elevated long pentraxin-3 (PTX3) levels are associated with the development of primary graft dysfunction (PGD) after lung transplantation. Abnormalities in innate immunity, mediated by PTX3 release, may play a role in PGD pathogenesis. Objectives: Our goal was to test whether variants in the gene encoding PTX3 are risk factors for PGD. Methods: We performed a candidate gene association study in recipients from the multicenter, prospective Lung Transplant Outcomes Group cohort enrolled between July 2002 and July 2009. The primary outcome was International Society for Heart and Lung Transplantation grade 3 PGD within 72 hours of transplantation. Targeted genotyping of 10 haplotype-tagging PTX3 single-nucleotide polymorphisms (SNPs) was performed in lung transplant recipients. The association between PGD and each SNP was evaluated by logistic regression, adjusting for pretransplantation lung disease, cardiopulmonary bypass use, and population stratification. The association between SNPs and plasma PTX3 levels was tested across genotypes in a subset of recipients with idiopathic pulmonary fibrosis. Measurements and Main Results: Six hundred fifty-four lung transplant recipients were included. The incidence of PGD was 29%. Two linked 5' region variants, rs2120243 and rs2305619, were associated with PGD (odds ratio, 1.5; 95% confidence interval, 1.1 to 1.9; P = 0.006 and odds ratio, 1.4; 95% confidence interval, 1.1 to 1.9; P = 0.007, respectively). The minor allele of rs2305619 was significantly associated with higher plasma PTX3 levels measured pretransplantation (P = 0.014) and at 24 hours (P = 0.047) after transplantation in patients with idiopathic pulmonary fibrosis. Conclusions: Genetic variants of PTX3 are associated with PGD after lung transplantation, and are associated with increased PTX3 plasma levels.     

The association between insulin-like growth factor-I and cardiac repolarization

ObjectivePrevious studies reported associations between insulin-like growth factor I (IGF-I) serum concentration and cardiac morbidity and mortality, but the association between IGF-I serum concentration and cardiac repolarization has not been investigated in a population-based study so far. Therefore, we analyzed the impact of IGF-I concentrations on QTc, QT and RR intervals in two population based studies, The Study of Health in Pomerania (SHIP) and the Rotterdam Study.Design457 individuals from SHIP and 155 individuals from the Rotterdam Study older than 55 years and without cardiovascular diseases and a left ventricular hypertrophy were investigated. IGF-I was determined by automated two-site chemiluminescence immunoassays and electrocardiograms were recorded by an ACTA electrocardiograph at a sampling frequency of 500 Hz. The association of IGF-I with QTc, QT and RR intervals was investigated by multivariable linear regression analyses adjusted for age, gender, diabetes mellitus, myocardial infarction, hypertension, body mass index, serum potassium and calcium in both studies separately and in pooled analysis.ResultsThere were no significant associations between log-transformed IGF-I and QTc interval in the single populations, whereas a significant inverse association was detectable in the pooled population (β, ? 15.6; 95%-confidence interval, ? 25.7, ? 5.5). The QTc interval was significantly higher in the first tertile of IGF-I compared to the third tertile (β, 5.4; 95%-confidence interval, 9.5–1.3) in the pooled analysis.ConclusionThe inverse association between IGF-I serum concentrations and QTc interval in our study is suggestive of a higher risk for cardiac arrhythmias and thus might provide additional evidence for increased cardiovascular mortality in subjects with low IGF-I secretion.     

Usefulness of Acarbose and Dietary Modifications to Limit Glycemic Variability Following Roux-en-Y Gastric Bypass as Assessed by Continuous Glucose Monitoring

Abstract Background: About 70% of the patients operated on for a gastric bypass (Roux-en-Y gastric bypass [RYGB]) suffer from dumping syndrome. In these patients, previous studies have demonstrated a high glycemic variability with hypoglycemia and with altered continuous glucose monitoring (CGM) profiles. The aim of this study was to evaluate the effect of treatment with dietary counseling plus acarbose administration on the symptoms and on the characteristics of the CGM profile. Subjects and Methods: Eight consecutive patients with dumping syndrome were given dietary counseling for 6 weeks and also treated with acarbose (50-100?mg three times a day). Their symptoms and the features of the CGM were compared before and after treatment. Results: The symptoms disappeared in seven patients. There was a significant increase in the time to the interstitial glucose (IG) peak and a reduction in the rate of the IG increase after a meal and in the rate of the IG decrease following the peak. The time below 60?mg/dL was significantly decreased, and the minimal IG value was significantly increased. The maximum and mean IG levels and the time above 140?mg/dL were decreased, but not significantly. Six patients spent more than 1% of the time with IG values below 60?mg/dL before treatment, but after treatment this was reduced to one patient. Before treatment only one patient had an IG level neither below 60 or above 140?mg/dL, and after treatment four patients were in this category. Conclusions: Dietary counseling and acarbose treatment eliminated the symptoms and improved the CGM profile of patients suffering from dumping syndrome after RYGB.