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Gregory S Thomas

Publications and source records attributed to Gregory S Thomas.

16 recordsLinked to original sources
PubMed2005

Role of noninvasive testing in the clinical evaluation of women with suspected coronary artery disease: Consensus statement from the Cardiac Imaging Committee, Council on Clinical Cardiology, and the Cardiovascular Imaging and Intervention Committee, Council on Cardiovascular Radiology and Intervention, American Heart Association.

Cardiovascular disease is the leading cause of mortality for women in the United States. Coronary heart disease, which includes coronary atherosclerotic disease, myocardial infarction, acute coronary syndromes, and angina, is the largest subset of this mortality, with >240,000 women dying annually from the disease. Atherosclerotic coronary artery disease (CAD) is the focus of this consensus statement. Research continues to report underrecognition and underdiagnosis of CAD as contributory to high mortality rates in women. Timely and accurate diagnosis can significantly reduce CAD mortality for women; indeed, once the diagnosis is made, it does appear that current treatments are equally effective at reducing risk in both women and men. As such, noninvasive diagnostic and prognostic testing offers the potential to identify women at increased CAD risk as the basis for instituting preventive and therapeutic interventions. Nevertheless, the recent evidence-based practice program report from the Agency for Healthcare Research and Quality noted the paucity of women enrolled in diagnostic research studies. Consequently, much of the evidence supporting contemporary recommendations for noninvasive diagnostic studies in women is extrapolated from studies conducted predominantly in cohorts of middle-aged men. The majority of diagnostic and prognostic evidence in cardiac imaging in women and men has been derived from observational registries and referral populations that are affected by selection and other biases. Thus, a better understanding of the potential impact of sex differences on noninvasive cardiac testing in women may greatly improve clinical decision making. This consensus statement provides a synopsis of available evidence on the role of the exercise ECG and cardiac imaging modalities, both those in common use as well as developing technologies that may add clinical value to the diagnosis and risk assessment of the symptomatic and asymptomatic woman with suspected CAD.

Coronary Artery Disease↗
PubMed2005

Potential indications for coronary angiography by computed tomography.

Recent advances in computed tomography technology have made possible angiographic images of relatively small, moving vascular structures such as the coronary arteries. Computed tomographic coronary angiography is an exciting modality which has several obvious advantages over invasive catheterization, such as its relatively noninvasive nature and rapid speed of acquisition. However, significant drawbacks still exist, including limitations of spatial and temporal resolution and radiation exposure. Computed tomographic coronary angiography appears best suited as a diagnostic modality for the patient population with a low-to-moderate pretest probability of coronary artery disease, and for specific indications such as the imaging of coronary anomalies and bypass grafts and before biventricular pacemaker placement and atrial fibrillation ablation.

Coronary Angiography↗
PubMed2004

Should simultaneous exercise become the standard for adenosine myocardial perfusion imaging?

Concomitant low-level treadmill exercise with adenosine pharmacologic stress (AdenoEx) during radionuclide myocardial perfusion imaging has become commonly used in recent years, particularly in large-volume laboratories. A number of studies have demonstrated a beneficial impact of AdenoEx protocols. These benefits include decreased side effects, improved safety and patient tolerance, improved target-to-background ratios because of less subdiaphragmatic activity, and improved sensitivity and defect reversibility. In light of these benefits, recent reviews and guidelines call for the addition of low-level exercise to adenosine stress whenever possible.

Adenosine↗
PubMed2004

Technetium 99m sestamibi myocardial perfusion imaging predicts clinical outcome in the community outpatient setting. The Nuclear Utility in the Community (NUC) Study.

OBJECTIVES: The purpose of this study was to evaluate the prognostic value of community-based myocardial perfusion imaging (MPI) and to assess the incremental value of individual components of (99m)Tc-sestamibi single photon emission computed tomography (SPECT). BACKGROUND: Although the most rapid growth of MPI has been in community outpatient laboratories, its prognostic value has not been validated in this setting. METHOD: We prospectively followed 1,612 consecutive patients undergoing stress (99m)Tc-sestamibi SPECT in an outpatient community laboratory who experienced 71 hard events over 24 +/- 7 months (0.2% lost to follow-up). RESULTS: Patients whose scans were normal incurred an annualized event rate of 0.4%, compared with 2.3% for those with abnormal scans (p < 0.0001). Subset analysis demonstrated comparable risk stratification for women and men, diabetics, patients with normal resting ECGs, and those referred for pharmacologic and exercise stress. After adjusting for pre-test variables, multivariable Cox regression analysis found the most potent independent components of MPI to be, in order of importance, transient ischemic dilation, extent of reversibility, post-stress ejection fraction, extent and severity of the stress perfusion defect, and the overall test result (normal or abnormal). Each 1% decrement of ejection fraction predicted a 3% increase in risk (p = 0.0009). Post-MPI angiography and revascularization increased commensurate with the extent and severity of MPI result. CONCLUSIONS: The prognostic value of perfusion imaging is portable and transferable to the outpatient community setting, with multiple components of MPI providing incremental prognostic information.

Aged↗
PubMedDate not supplied

Should we screen asymptomatic individuals for coronary artery disease or implement universal lipid-lowering therapy?

The lifetime risk of developing coronary heart disease after age 40 has been estimated to be 49% and 32% in men and women, respectively. Including other diseases secondary to atherosclerosis makes the likelihood of developing cardiovascular disease even greater. Lacking an adequate screening test for subclinical cardiovascular disease, or for those in whom it will develop, our current national prevention and treatment strategy is to screen for risk factors of coronary artery disease (CAD), treating only those at greatest risk. Although pharmacologic lipid-lowering therapy has proven to be effective at reducing the development and manifestations of CAD, as well as remarkably safe, our current strategy withholds treatment of many in whom cardiovascular disease will ultimately develop. An alternate strategy is to implement universal lipid-lowering therapy, initiated in men at age 30 and at the time of menopause in women. Such a policy would not limit effective treatment to only those at greatest risk. While the cost of such a program would be substantial, although decreasing with the increasing availability of generic agents, this must be weighed against the direct and indirect costs of cardiovascular disease, estimated to be $368 billion in 2004. If such a strategy were implemented, the goal of screening would shift from CAD detection to detection of a disease burden such that therapies shown to decrease events among those with manifest CAD would be expected to benefit. Such treatments currently include aspirin, beta blockers, angiotensin-converting enzyme inhibitors, and revascularization.

Adult↗