Assessment of right ventricular perfusion after right coronary artery occlusion by myocardial contrast echocardiography.

Objectives: The purpose of this study was to examine the ability of myocardial contrast echocardiography (MCE) to assess right ventricular (RV) perfusion.

Background: Although MCE can readily assess left ventricular perfusion abnormalities, there are no data regarding the ability to assess RV perfusion abnormalities.

Methods: The right coronary artery (RCA) was occluded in 10 open-chest dogs.

Effect of microbubble fragility on transit rate measurement by contrast echography.

We sought to propose a simplified method to measure flow velocity based on ultrasonic microbubble destruction, and investigated the effect of microbubble shell fragility on such measurement. Acoustic density (AD) from the second harmonic short axis image of flow was obtained at variable velocities (2 to 73 mm/s) in an in vitro model during long (1000 ms) and short (33 ms) interval ultrasound (US) pulsing, allowing complete and partial microbubble replenishment between pulses, respectively. Microbubbles with shell elastic modulus of 0.

Coxibs--beyond the GI tract: renal and cardiovascular issues.

Although the coxibs have demonstrated superior gastrointestinal safety compared to traditional non-selective NSAIDs, questions remain regarding their effects on the renal and cardiovascular systems. In terms of renal function, both Type 1 and Type 2 cyclooxygenase (COX-1 and COX-2) are expressed constitutively in the kidney. Prostaglandins do not play a major role in the maintenance of renal function in healthy individuals but they become profoundly important in certain clinical situations such as renal stress, or volume depletion.

A historical overview of enhanced external counterpulsation.

Angina remains a significant health problem in the United States and the world. Although there are a variety of pharmacologic and interventional therapies to treat angina, many patients are not adequately helped by these treatments. Enhanced external counterpulsation (EECP) is an effective, noninvasive technique designed to decrease the frequency and duration of anginal episodes, as well as increase exercise duration in patients with acute angina.

Physical principles of microbubble ultrasound contrast agents.

Early contrast agents could not achieve left-sided cardiac opacification because these microbubbles could not traverse the pulmonary circulation and remain intact. The specific shell material and gas used determine the properties of individual microbubbles, including fragility, persistence, and resonance. Persistence, perhaps the most important property of a microbubble, has been achieved by second-generation agents through the use of shells or surfactants and by substituting high-density, high molecular weight gas for air.

Correlation of left ventricular diastolic filling characteristics with right ventricular overload and pulmonary artery pressure in chronic thromboembolic pulmonary hypertension.

Objectives: This study was designed to determine a quantitative relationship between right ventricular (RV) pressure overload and left ventricular (LV) diastolic filling characteristics in patients with chronic thromboembolic pulmonary hypertension (CTEPH).

Background: Right ventricular pressure overload in patients with CTEPH causes abnormal LV diastolic filling. However, a quantitative relationship between RV pressure overload and LV diastolic function has not been established.

Limited cardiac ultrasound examination for cost-effective echocardiographic referral.

Background: Although a standard echocardiogram is frequently requested and requires significant resources, few data exist on methods to improve referral for this examination. Therefore, we sought to determine the diagnostic value of a limited echocardiographic examination and to predict the cost-effectiveness of a limited imaging strategy on echocardiographic referral.

Methods: A limited echocardiographic examination was reviewed for abnormalities and compared with standard echocardiographic findings.

Contrast echocardiography can assess risk area and infarct size during coronary occlusion and reperfusion: experimental validation.

Objectives: We sought to validate the ability of real-time myocardial contrast echocardiography (MCE) measures of opacification defect and contrast refilling parameters to estimate risk area (RA) and infarct area (IA) during coronary occlusion and reperfusion.

Background: No data exist establishing the accuracy of MCE in determining RA and IA size. We hypothesized that in the setting of coronary occlusion, MCE should identify RA as a perfusion defect early after bubble destruction, collateral flow to viable myocardium as opacification late during refilling and IA as absent opacification.

Hemodialysis access assessment with intravascular ultrasound.

Reliable identification and treatment of specific hemodialysis access complications may improve access patency and result in significant cost reduction. Angiography is the gold standard for the evaluation of vascular access; however, it has significant limitations. Intravascular ultrasound (IVUS) is a relatively new technique capable of detecting subtle vascular abnormalities.

Relative risk of cardiovascular events in patients with rheumatoid arthritis.

Rheumatoid arthritis (RA) is associated with increased comorbidity and mortality resulting from cardiovascular disease. A review of past and recent studies suggests that inflammation and thrombosis may provide a link between both diseases. This association has significant clinical implications for therapy, because many of the drugs used in the symptomatic treatment of RA, such as nonsteroidal anti-inflammatory drugs and the new cyclooxygenase (COX)-2-specific inhibitors, affect mediators of both inflammation and thrombosis.