Recent Trends in Utilization of Implantable Cardioverter-Defibrillators in Survivors of Cardiac Arrest in the United States

Background: Cardiac arrest (CA) is a class I indication for implantable defibrillator (ICD) therapy. We studied the trend of ICD utilization in survivors of CA in the US population between 2002 and 2006.
Methods: We searched the National Hospital Discharge Survey for patients admitted with the primary diagnosis of CA who survived to hospital discharge. Patients with a concomitant diagnosis of acute myocardial infarction or previous ICD implantation were excluded.
Results: From 2002 to 2006, 758 patients were surveyed representing 88,920 discharges. Of those, 396 (52.2%) representing 48,098 discharges did not survive to hospital discharge. Of the remaining 362 (representing 38,855) patients, 38.4% received an ICD prior to discharge. Independent predictors of in-hospital mortality included older age, female gender, black race, smaller hospital of discharge, and a higher number of organ failures (P < 0.001 for all). Using logistic regression, patients who were discharged with an ICD were more likely to have been discharged from a larger hospital (odds ratio = 2.35 for each additional 100 beds, P < 0.001) and to be less sick (odds ratio = 0.85 for each additional organ failure, P < 0.001). There was no gender or racial discrepancy in the ICD utilization after CA.
Conclusions: Despite their class I indication after CA, ICDs continue to be underutilized, but the previously documented racial gaps have disappeared. Our data reveal a large discrepancy in ICD utilization by the size of the discharge hospital, which may suggest regional influences and gaps in resource allocations. Future studies looking into the root causes of these discrepancies and possible remedies are warranted.     

Acyclic peptides as conformational models

The tripeptide Boc-Aib-Leu-Pro-NHMe crystallizes in the orthorhombic space group P2₁2₁2₁ with a = 9.542, b = 15.200, c = 18.256 Å and Z = 4. Each peptide is associated wth two water molecules in the asymmetric unit of the crystal. The structure has been solved by direct methods and refined to an R-value of 0.069. The peptide adopts a structure without any intramolecular hydrogen bond. The three residues occupy distinctly different regions of the Ramachandran map: Aib in the left-handed 3₁₀-helical region (± = 67°, ± = 23°), Leu in the β-sheet region (± = - 133°, ± = 142°) and Pro in the poly (Pro) II region (± = - 69°, ± = 151°). An interesting observation is that each water molecule participates in four hydrogen bonds with distorted tetrahedral coordination about the oxygen atom.     

Synthesis and characterization of 1-13C-DLeu12,14 gramicidin A

The ¹³C-D-Leu^12,14 gramicidin A was synthesized by the solid phase method incorporating ¹³C-D-leucine in positions 12 and 14 with about 25 and 50% enrichment, respectively. The pentadecapeptide was removed from the resin by ethanolamine treatment, with the N-protecting group (Boc) still on. After removal of the protecting group, the peptide was formylated and purified by preparative t.l.c. to obtain ¹³C-D-Leu^12,14 gramicidin A in a very pure state in an overall yield of about 12.5%. The peptide was then thoroughly characterized by HPLC which gave one single peak with the same retention time as that of Val¹-gramicidin A of the natural gramicidin mixture. The CD spectra of the synthetic and the HPLC purified natural Val¹ -GA were obtained and found to be identical, indicating the optical purity of the sample. The synthetic GA was characterized by ¹³C n.m.r. spectrum and compared with that of natural GA. Single channel conductance parameters of the synthetic GA were determined and found to be indistinguishable from those of natural Val¹-GA in lipid bilayer membranes and the mean channel lifetime was found to be as reported earlier by others.     

BRONCHIAL ARTERIOGRAPHY AND TRANSCATHETER EMBOLIZATION IN MANAGEMENT OF SEVERE HAEMOPTYSIS

The purpose of this study was to assess the effectiveness of bronchial arteriography and transcatheter embolization in treatment of severe haemoptysis. Forty five patients with severe haemoptysis were evaluated by means of bronchial arteriography and study of non bronchial systemic arteries and underwent transcatheter embolization. Specific causes of haemoptysis were Tuberculosis (n=37), Tuberculosis with Aspergilloma (n=4) and bronchiectasis (n=4). Gel foam pellets and polyvinyl alcohol (PVA) particles were used as embolic material in 36 patients and 9 patients respectively. The angiographic signs of haemorrhage encountered were extravasation of contrast in 2 patients (4.4%), hypervascularisation in 42 (93.3%), broncho-pulmonary shunt in 13 (28.8%) and bronchial artery aneurysm in 1 patient (2.2%). Immediate control of bleeding occurred in 44 (97.7%) of 45 patients after embolization. Recurrent haemoptysis occurred in 4 cases (11.9%) more than 1 month after embolization but bleeding was less severe, than before treatment. This study suggests that bronchial artery embolization is an effective method of managing patients with severe haemoptysis, minor bleeding recurrences appear to be relatively infrequent.KEYWORDS: Embolization, Haemoptysis, Lung haemorrhage