Acoustic cardiographic recording during ventricular fibrillation

This is the second case report in literature that describes the simultaneous acoustic cardiographic, electrocardiographic, and invasive hemodynamic events that occurred before, during and after ventricular fibrillation that was successfully cardioverted to sinus rhythm. The absence of heart sounds, which are linked to the lack of effective myocardial contractility, correlated well with invasive hemodynamic data, indicating the lack of perfusion during ventricular fibrillation. These observations, coupled with the challenges of pulse detection as a sign of adequate perfusion during resuscitation suggest that acoustic cardiography may be a potentially effective supplemental diagnostic tool during the resuscitation of malignant arrhythmias.     

Low Ejection Fraction Predicts Shortened Survival in Patients Undergoing Infrainguinal Arterial Reconstruction

Background With the advent of endovascular therapy for lower extremity ischemia it is important to better determine what factors may affect the outcome. The goal of the present study was to evaluate whether ejection fraction (EF) is predictive of outcome in infrainguinal arterial reconstruction. Methods We retrospectively reviewed 736 patients undergoing 897 infrainguinal arterial reconstructions from July 1999 to February 2002. Patients were divided into two groups: group I contained 54 patients with an EF<35% and group II had 216 patients with an EF ≥35%. The outcome evaluated was major adverse clinical events (MACEs), defined as postoperative myocardial infarction (MI), arrhythmia, congestive heart failure (CHF), and perioperative mortality. Results Major adverse clinical events occurred in 20.3% of patients (11/54) in group I and 10.6% patients (23/216) in group II (p = 0.068). Group I had a trend toward a greater incidence of MACEs compared to group II. Two-year survival for group I was 61.7%, whereas survival for group II was 78.4% (p = 0.0085). Conclusions Low EF predicts a significantly shortened 2-year survival after infrainguinal arterial reconstruction and a trend toward increased perioperative complications. This is another factor to be considered in choosing open versus endovascular options.     

Oscillatory vagal maneuvers produce ventricular entrainment in patients with atrial fibrillation

Background  

Atrial fibrillation (AF) is the most common sustained dysrhythmia and appears to be an independent predictor of sudden cardiac death. The irregular ventricular rhythm contains both linear and non-linear patterns; however, it remains unclear whether vagally mediated effects are present within these patterns.     

Model for assessment of proficiency of human immunodeficiency virus type 1 sequencing-based genotypic antiretroviral assays

Use of sequencing-based genotyping as a diagnostic assay for human immunodeficiency virus (HIV) antiretroviral resistance is increasing. Periodic evaluation of the proficiency of laboratories performing this assay should be established. It is important to identify components of the assay that influence the generation of reliable sequencing data and that should and can be monitored. A model was developed to determine what parameters were reasonable and feasible for assessing the performance of genotyping assays. Ten laboratories using the genotyping platform, HIV-1 Genotyping System (HGS) v. 1 and software versions 1.1 or 2.0, participated in two rounds of testing. For each round, each group was sent a panel consisting of three clinical samples to sequence in real time. Six months later, seven laboratories using the TRUGENE HIV-1 Genotyping Kit participated in a separate round, working with both panels at the same time. Analysis of the data showed that one main indicator of genotyping proficiency was achievement of > or =98% sequence homology of a sample tested to a group consensus sequence for that sample. A second was concordant identification of codons at sites identified with resistance mutations in the sample, although scoring of these criteria is still undetermined from this study. These criteria are applicable to all sequence-based genotyping platforms and have been used as a baseline for assessing the performance of genotyping for the determination of antiretroviral resistance in our ongoing proficiency program.