Biomedical subjects

Anthony N DeMaria

Publications and source records attributed to Anthony N DeMaria.

77 records · Page 5Linked to original sources

PubMed2002

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. METHODS: Three hours of coronary occlusion and reperfusion were each produced in 11 dogs in which real-time MCE was performed during intravenous infusion of Sonovue (Bracco). Real-time contrast echocardiography was performed at baseline, during occlusion and reperfusion. Early (BEGIN) and end (END) images from a FLASH refilling sequence were acquired, as well as late refilling images (LATE) 1 min after FLASH. Real-time contrast echocardiography defect size and quantitative refilling parameters were compared with RA and IA determined by tissue staining. RESULTS: During occlusion, defect size varied with refilling time; defects from BEGIN images correlated best to RA and those from LATE images to IA. Refilling parameters, but not LATE peak intensity, did not predict the IA size during occlusion. During reperfusion, defects from BEGIN images were well correlated to RA and END images to IA, whereas peak plateau intensity and refilling slope parameters predicted IA size. CONCLUSIONS: Real-time contrast echocardiography defect size varies throughout microbubble refilling. Appropriately selected defect sizes and refilling parameters provide estimates of RA and IA during coronary occlusion and reperfusion.

Animals↗

PubMed2002

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. Recent studies have elucidated the potential effects of COX-2-specific inhibitors on thrombogenic events and their potential impact on cardiovascular disease. Although a causal effect of these drugs to increase the risk of cardiovascular disease has not been established, further investigation is needed on the effects of COX-2-specific inhibitors on cardiovascular risk. Such data would be of particular importance in determining appropriate therapeutic approaches to the treatment of patients with RA who are also at risk for cardiovascular events.

Aged↗

PubMed2002

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. Since the early 1960s, the technology of EECP has been thoroughly refined. In addition, a number of important clinical trials have provided evidence for its effectiveness. Continuing research is needed to determine the best patients for EECP and its appropriate clinical application.

Angina Pectoris↗

PubMed2002

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. To investigate the safety, feasibility, and accuracy of IVUS imaging to detect hemodialysis access complications, including stenoses, graft deterioration, and thrombus, we performed 31 IVUS imaging studies in 22 hemodialysis patients. Nineteen studies were performed in the dialysis unit, and 12 studies in the angiography suite. The IVUS catheter was inserted into the graft through the access used for hemodialysis. Findings of 21 studies (17 patients) imaged on the same day by both angiography and IVUS were compared. Grafts and vessels were successfully imaged using IVUS in 29 of 31 studies. There were no adverse effects caused by IVUS. Angiography assessed 17 of 54 vessel segments as normal versus 9 of 54 segments by IVUS (P < 0.001). Angiography detected lesions in 25 segments as opposed to 33 segments by IVUS (P < 0.001). A thrombus was detected in 32 of 54 vessel segments by IVUS, but in only 1 of 54 segments by angiography (P < 0.001). In conclusion, IVUS imaging is feasible and safe to assess hemodialysis access in the angiographic suite and dialysis unit. IVUS detected more vascular abnormalities than angiography. IVUS may be a useful independent imaging and screening modality in the assessment of dialysis access complications, which may help increase graft patency and reduce cost.

Angiography↗

PubMed2002

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. Assuming an imaging strategy in which a normal limited echocardiographic examination would negate the need for standard echocardiography, we calculated the diagnostic yields, the number of full echocardiographic studies eliminated, and the number of abnormal cases missed. We also stratified data by patient age (< or > or = 65 years), inpatient versus outpatient status, gender, referral diagnosis, and referring physician subspecialty. RESULTS: In 151 outpatients, overall diagnostic yield was 47% (95% CI [39%, 55%]), and was lower in those younger than 65 years, in women, and in noncardiologist referral. In 155 inpatients, yields were 75% (95% CI [67%, 83%]) and were also related to age, but not to gender, diagnosis, and physician subspecialty. Sensitivity, specificity, negative and positive predictive values, and accuracy for the limited echocardiographic examination was 77%, 72%, 67%, 81%, and 75%, respectively. The limited imaging strategy negated 70% of studies in the outpatient group younger than 65 years, with a less than 5% chance of missing a clinically significant finding. CONCLUSION: A limited echocardiographic imaging strategy is most cost-effective when used in young outpatients, where it can result in a substantial reduction in referral for standard echocardiography while rarely missing findings.

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