Cardiac resynchronization therapy: Part 1--issues before device implantation.

Cardiac resynchronization therapy (CRT) has been used extensively over the last years in the therapeutic management of patients with end-stage heart failure. Data from 4,017 patients have been published in eight large, randomized trials on CRT. Improvement in clinical end points (symptoms, exercise capacity, quality of life) and echocardiographic end points (systolic function, left ventricular size, mitral regurgitation) have been reported after CRT, with a reduction in hospitalizations for decompensated heart failure and an improvement in survival.

Tissue harmonic imaging for standard left ventricular measurements: fundamentally flawed?

Tissue harmonic imaging (THI) is a B mode imaging technique that improves echocardiographic image quality by reducing superficial artefact. The modality increases image signal-to-noise ratio at the expense of reduced axial resolution. While the qualitative improvements of harmonic echocardiographic imaging are widely accepted, the degree to which this is translated into improved quantitative measurements and whether THI-derived measurements result in systematic bias continue to be areas of uncertainty.

DNA-based species delineation in tropical beetles using mitochondrial and nuclear markers.

DNA barcoding has been successfully implemented in the identification of previously described species, and in the process has revealed several cryptic species. It has been noted that such methods could also greatly assist in the discovery and delineation of undescribed species in poorly studied groups, although to date the feasibility of such an approach has not been examined explicitly. Here, we investigate the possibility of using short mitochondrial and nuclear DNA sequences to delimit putative species in groups lacking an existing taxonomic framework.

Trans-oceanic and endemic origins of the small minnow mayflies (Ephemeroptera, Baetidae) of Madagascar.

We investigated the relative importance of dispersal and vicariance in forming the Madagascar insect fauna, sequencing approximately 2300bp from three rRNA gene regions to investigate the phylogeny of Afrotropical small minnow mayflies (Ephemeroptera: Baetidae). Six lineages contained trans-oceanic sister taxa, and variation in genetic divergence between sister taxa revealed relationships that range from very recent dispersal to ancient vicariance. Dispersal was most recent and frequent in species that spend the larval stage in standing water, adding to evidence that these evolutionarily unstable habitats may select for ecological traits that increase dispersal in insects.

Real-time three-dimensional echocardiography: a novel technique to quantify global left ventricular mechanical dyssynchrony.

Background: Left ventricular (LV) mechanical dyssynchrony (LVMD) has emerged as a therapeutic target using cardiac resynchronization therapy (CRT) in selected patients with chronic heart failure. Current methods used to evaluate LVMD are technically difficult and do not assess LVMD of the whole LV simultaneously. We developed and validated real-time 3D echocardiography (RT3DE) as a novel method to assess global LVMD.

The effect of refurbishing a UK steel plant on PM10 metal composition and ability to induce inflammation.

Background: In the year 2000 Corus closed its steel plant operations in Redcar, NE of England temporarily for refurbishment of its blast furnace. This study investigates the impact of the closure on the chemical composition and biological activity of PM10 collected in the vicinity of the steel plant.

Methods: The metal content of PM10 samples collected before during and after the closure was measured by ICP-MS in order to ascertain whether there was any significant alteration in PM10 composition during the steel plant closure.

Stress echocardiography for the diagnosis and risk stratification of patients with suspected or known coronary artery disease: a critical appraisal. Supported by the British Society of Echocardiography.

Stress echocardiography today has matured into a robust and reliable technique not only for the diagnosis of suspected coronary artery disease (CAD) but also for the accurate risk stratification of patients with suspected and established CAD. This is mainly because of rapid advances in image acquisition, digital display, and the development of harmonic and contrast imaging. Stress echocardiography today is also utilised in patients with heart failure both for assessing the cause of heart failure and determining the extent of hibernating myocardium.

Sonovue improves endocardial border detection and variability in assessing wall motion score and ejection fraction during stress echocardiography.

Background: Stress echocardiography is useful for assessing patients with coronary artery disease unable to undergo formal exercise testing. Considerable skill is required to avoid large intra- and inter-observer variability due to poor endocardial definition. Intravenous ultrasound contrast agents are now available which may improve this variability.

Echocardiographic evaluation of cardiac dyssynchrony for predicting a favourable response to cardiac resynchronisation therapy.

Cardiac resynchronisation therapy (CRT) is an established therapy for patients with heart failure with wide QRS duration. Recent studies observed that assessment of systolic dyssynchrony is an important diagnostic tool as the treatment involves the re-coordination of regional wall contraction within the left ventricle. Therefore, the effectiveness of CRT depends heavily on whether systolic dyssynchrony is present before the treatment.

KChIPs and Kv4 alpha subunits as integral components of A-type potassium channels in mammalian brain.

Voltage-gated potassium (Kv) channels from the Kv4, or Shal-related, gene family underlie a major component of the A-type potassium current in mammalian central neurons. We recently identified a family of calcium-binding proteins, termed KChIPs (Kv channel interacting proteins), that bind to the cytoplasmic N termini of Kv4 family alpha subunits and modulate their surface density, inactivation kinetics, and rate of recovery from inactivation (An et al., 2000).

Cost of a pharmacist-directed intervention to increase treatment of hypercholesterolemia.

Study Objective: To evaluate the cost of a pharmacist-directed intervention that prompts physicians to treat hypercholesterolemia more aggressively in patients with coronary heart disease (CHD).

Methods: Health care resource use and CHD outcomes were evaluated for 612 patients with CHD followed for 2 years after an index hospitalization for an ischemic event. After discharge, the physicians of 309 patients who had been admitted from January 1--March 31, 1999, were contacted by telephone and mail concerning lipid profiles and statin therapy.

Effect of harmonic imaging on the measurement of ultrasonic integrated backscatter and its interpretation in patients following myocardial infarction.

Background: Recently, we have demonstrated that cyclic variation in ultrasonic integrated backscatter (IBS) can be used to predict patency of the infarct related artery (IRA) post-acute myocardial infarction (AMI). Second harmonic imaging has become widely available on ultrasound machines and enhances endocardial definition. The effect of harmonic imaging on the measurement and interpretation of cyclic IBS is unknown.

The treatment of de novo acromegalic patients with octreotide-LAR: efficacy, tolerability and cardiovascular effects.

Aim: Somatostatin analogues are normally used as adjunctive therapy to surgery and radiotherapy in management of acromegaly. We studied the effects of de novo OCT-LAR treatment on growth hormone (GH) suppression, tumour size, cardiovascular function, clinical symptoms, signs and quality of life in 9 newly diagnosed acromegalic patients.

Methods: Patients commenced OCT-LAR 20 mg IM monthly for 2 months.

Normal values of left ventricular systolic and diastolic function derived from signal-averaged acoustic quantification waveforms: a multicenter study.

Automated border-detection techniques such as acoustic quantification have proven accurate and useful for quantifying left ventricular (LV) function. We acquired LV acoustic quantification waveforms from the parasternal short-axis window in 140 healthy patients in the age range of 16 to 78 years. Signal-averaged waveforms were analyzed for parameters of systolic and diastolic performance.

Rhabdomyolysis associated with simvastatin-nefazodone therapy.

Simvastatin is a hydroxymethyl glutaryl coenzyme A reductase inhibitor commonly used to treat patients with hyperlipidemia. It is a safe and effective medication in most patients when used appropriately. A serious side effect known as rhabdomyolysis may rarely occur in patients who take simvastatin, especially at higher doses and with agents that interact and increase the level of simvastatin in the blood.

Myocardial contrast echocardiography (MCE) with triggered ultrasound does not cause premature ventricular complexes: evidence from PB127 MCE studies.

Previous studies suggest that myocardial contrast echocardiography using high mechanical index triggered ultrasound can be associated with increased frequency of the premature ventricular complex (PVC). However, this association has not been systematically examined. PB127 (Point Biomedical Corp, San Carlos, Calif) is a novel microsphere designed for evaluation of myocardial perfusion with ultrasound.

Comparison of usefulness of dipyridamole stress myocardial contrast echocardiography to technetium-99m sestamibi single-photon emission computed tomography for detection of coronary artery disease (PB127 Multicenter Phase 2 Trial results).

We hypothesized that assessment of hyperemic myocardial blood flow (MBF) velocity using myocardial contrast echocardiography (MCE) can detect coronary artery disease (CAD). We also postulated that only a single MCE study during stress is required for the detection of CAD in patients with normal function at rest. Patients with known or suspected CAD referred for dipyridamole stress technetium-99m sestamibi single-photon emission computed tomographic (SPECT) studies were enrolled.

Manipulation of the cervical spine.

In New Zealand, a new approach to manual therapy of the cervical spine has integrated physiotherapy and osteopathy techniques. The combination of the philosophies of these two professions has added a new dimension to the management of cervical spine pain. Emphasis is placed on issues of safety, such as the degree of cervical rotation and comfort for both the patient and the therapist.