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Lori B Croft

Publications and source records attributed to Lori B Croft.

11 recordsLinked to original sources
PubMed2006

A pilot study of the clinical impact of hand-carried cardiac ultrasound in the medical clinic.

BACKGROUND: Small, hand-carried ultrasound devices have become widely available, making point-of-care echocardiograms (echos) accessible to all medical personnel as a means to augment and improve the increasingly inefficient physical examination. This study was designed to determine the clinical utility of hand-carried echo by medical residents in clinical decision making. METHODS: Nine residents underwent brief, practical echo training to perform and interpret a limited hand-carried echo as an integral component of their office examination. The residents' hand-carried echo consisting of four basic views to define left ventricular (LV) function and wall thickness, valvular disease, and any pericardial effusions was compared to one performed by a level III echocardiographer. RESULTS: Seventy-two consecutive medical clinic patients were enrolled with an average image acquisition time of 4.45 minutes. Residents obtained diagnostic images in 94% of the cases and interpreted them correctly 93% of the time. They correctly identified 92% of the major echo findings and 78% of the minor findings. Their diagnosis of LV dysfunction, valvular disease, and LV hypertrophy improved by 19%, 39%, and 14% with hand-carried echo compared to history and physical alone. Management decisions were reinforced in 76% and changed in 40% of patients with the use of hand-carried echo. CONCLUSION: This study demonstrates that it is possible to train medical residents to perform an effective and reasonably accurate hand-carried echo during their physical examination, which can impact clinical management.

Chi-Square Distribution↗
PubMed2005

Immediate upright post-treadmill exercise echocardiographic imaging.

Using standard treadmill exercise techniques, it has been shown that postexercise echocardiographic imaging can be performed safely and effectively while a patient is still standing on the treadmill. Furthermore, upright imaging can be initiated earlier and completed at a higher heart rate than standard supine imaging. Patients who can ambulate but with decreased agility and maneuverability and who would otherwise have been denied treadmill tests may be eligible for upright poststress imaging.

Echocardiography↗
PubMed2005

Feasibility and potential clinical utility of goal-directed transthoracic echocardiography performed by noncardiologist intensivists using a small hand-carried device (SonoHeart) in critically ill patients.

OBJECTIVE: This study was designed to assess the clinical applicability of a small, handheld, portable transthoracic echocardiography device by noncardiologist intensivists. DESIGN: Prospective, observational study. After 10 one-hour tutorials, intensivists performed a limited transthoracic echocardiography (TTE) (2-4 views, without Doppler or M-mode) examination with the 5.6-lb SonoHeart Echo System (SonoSite, Bethell, WA) on critically ill patients admitted to the surgical intensive care unit. After initial cardiac clinical assessment in 90 patients, a limited TTE was performed by an intensivist to assess left ventricular (LV) function and LV volume status. Each study was immediately reviewed and repeated by an echocardiographer to determine the technical quality of the TTE and the accuracy of the intensivist's interpretation. Data were analyzed and presented in proportions using descriptive statistics. SETTING: Surgical intensive care unit of an academic medical center. PARTICIPANTS: Ninety critically ill adult patients. INTERVENTIONS: After initial cardiac clinical assessment, a limited TTE was performed by an intensivist to assess LV size and function, to rule out significant pericardial effusions, and to estimate circulatory volume. RESULTS: Intensivists successfully performed a diagnostic limited TTE in 94% of patients and interpreted their studies correctly in 84%. Limited TTE provided new cardiac information and changed management in 37% of patients. TTE added useful information in an additional 47% of patients but did not alter immediate management. The mean "goal-directed TTE" acquisition time was 10.5 +/- 4.2 minutes. CONCLUSION: After a brief formal training in using this handheld echocardiographic system in intensive care unit patients, surgical intensivists successfully performed and correctly interpreted a limited TTE in critically ill patients. Limited TTE provided new information and altered management in a significant number of patients. This study supports incorporating bedside goal-directed, limited TTE into intensivists' training programs.

Adult↗
PubMed2004

Age-related prevalence of cardiac valvular abnormalities warranting infectious endocarditis prophylaxis.

The goal of our study was to determine the prevalence of older patients with cardiac valvular abnormalities warranting endocarditis prophylaxis. We performed a retrospective analysis of 1,000 randomly selected echocardiograms (inpatients and outpatients) from our tertiary care institution. We found that the prevalence of valvular abnormalities increased significantly with age, and that 50% of patients > or =60 years of age warranted endocarditis prophylaxis using current guidelines. With the aging population of the United States and the negative consequences of widespread antibiotic prophylaxis, further investigation is needed to identify patients who are truly at risk for infectious endocarditis.

Adolescent↗
PubMed2003

Calcific aortic stenosis: new pathophysiologic insights and possible new medical therapy.

Aortic stenosis is a progressive disease of aging with serious complications. A common disease of the elderly, it may inexorably progress to stenosis. Recent retrospective studies have correlated risk factors commonly associated with coronary and vascular atherosclerosis with an accelerated rate of aortic valve stenosis. Although hydroxymethyl glutaryl co-enzyme A reductase inhibitor (statin) treatment therapy has been shown to delay the rate of progression of valvular aortic stenosis, the salutary mechanism of the statin may be cholesterol-lowering and/or anti-inflammatory. Further prospective studies are warranted to investigate the mechanism and medical therapy of aortic sclerosis and stenosis.

Aortic Valve Stenosis↗
PubMed2003

Can hand-carried ultrasound devices be extended for use by the noncardiology medical community?

Echocardiography (echo) is a powerful, noninvasive, inexpensive diagnostic imaging technique that provides important information in a variety of cardiovascular diseases. Echo provides rapid information regarding ventricular and valvular function in the clinical management of patients. Smaller, relatively inexpensive hand-carried cardiac ultrasound (HCU) devices have become commercially available, which can be used for diagnostic cardiac imaging. Because of their relative ease of use, portability, and affordable cost, these new hand-held systems have made point-of-care (bedside) echocardiography available to all medical personnel. The rate-limiting step to the widespread use of this technology is the lack of personnel with echo training at the immediate contact point with patients. Although extensive training and experience are needed to acquire and interpret a complete echo, training medical personnel to perform and interpret a limited echo (defined as a brief, diagnosis focused exam) may fully exploit the potential of echo as a point-of-care diagnostic tool and may be accomplished in a short period of time. Presently there are guidelines for independent competency in echocardiography and HCU echo established by several professional organizations and as a result of these rigorous guidelines, other noncardiology medical professionals who could practically derive the greatest benefit are discouraged and virtually precluded from utilizing echo during the initial encounter with the patient. However, there is now a growing body of literature in a diverse group of noncardiology medical personnel that demonstrates that it is possible to quickly and effectively train them to perform and interpret limited echocardiograms. Medical students, medical residents, cardiology fellows with limited experience, emergency department physicians, and surgical intensive care unit staff have all been evaluated after only brief, focused training periods, and investigators found that HCU echo provided important new information, changed therapeutic management, and was vastly superior to the physical exam alone with an acceptable overall level of accuracy. The contribution of echocardiography to the field of cardiovascular disease since its invention has been significant and the newer compact, portable, ultrasound systems have the potential to revolutionize the utilization and availability of echocardiography. To maximize integration of echo into medical practice, physicians and physician extenders could be trained to perform and interpret limited echo to complement their clinical examination and improve their diagnostic skills. The challenge is to provide practical training programs to assure competency in performing point of care echocardiograms.

Emergency Service, Hospital↗
PubMed2003

The electrocardiogram as a predictor of left ventricular systolic function: correlation with gated SPECT imaging.

BACKGROUND: Left ventricular systolic function, expressed as ejection fraction (LVEF), is an important determinant of prognosis for cardiac disease, and is the basis for therapeutic decisions. Several imaging modalities are used for measuring LVEF. All require time, appropriate technology and professional attention, and most expose patients to small doses of radiation. We studied the correlation between surface electrocardiogram (ECG) and nuclear angiography in 673 patients. The purpose of our study was to determine whether normal ECG reliably predicts normal LVEF. Gated single-photon emission computed tomography (GSPECT) imaging was used as the reference. METHODS AND RESULTS: A total of 673 patients (273 men, 400 women) with known or suspected coronary artery disease and normal ECGs underwent GSPECT Tc99m sestamibi stress tests (exercise stress for 405 patients, pharmacological stress for 268). Post-stress images were gated 30 60 minutes after stress. LVEF was determined using QGS Cedar-Sinai commercial software. Results were grouped according to type of stress (exercise or pharmacological) and the interpretation of perfusion imaging (normal or abnormal). LVEF was similar after exercise and pharmacological stress in patients with normal (69 7 vs 69 7) and abnormal (61 9 vs 62 10) stress perfusion. LVEF was < 45% (lower limit of normal) in only 7/673 patients (1%). CONCLUSIONS: Normal ECG reliably predicts normal LVEF measured by post-stress GSPECT. Absolute LVEF value is lower in patients with stress perfusion defects.

Electrocardiography↗
PubMedDate not supplied

SPECT myocardial perfusion imaging in morbidly obese patients: image quality, hemodynamic response to pharmacologic stress, and diagnostic and prognostic value.

BACKGROUND: Obesity is a growing epidemic in the United States, and little is known about the characteristics of the morbidly obese population (body mass index [BMI] > or = 40 kg/m2) undergoing stress myocardial perfusion imaging (MPI). METHODS AND RESULTS: We retrospectively reviewed all consecutive morbidly obese patients without known coronary artery disease presenting for a clinically indicated technetium 99m (Tc-99m) gated stress single photon emission computed tomography imaging study over a 42-month period. Studies were analyzed for image quality, for the contribution of attenuation correction to image interpretation, and for the hemodynamic response to pharmacologic stress. In patients who subsequently had cardiac catheterization, the results were compared with those from the initial MPI study, and the Social Security Death Index and hospital medical records were searched to the assess survival rate in the entire cohort. A total of 433 patients were identified with a mean BMI of 47.3 +/- 8 kg/m2 and a mean Tc-99m stress dose of 35.6 +/- 5.4 mCi. Image quality was good in 61% of the patients, adequate in 37%, and poor in 2%. It was found to be dependent on the stressor used (better with exercise) but did not correlate with increasing weight or BMI. Attenuation correction was used in 95% of the studies reviewed and was helpful for image interpretation in 60%. The heart rate response to dipyridamole and adenosine was more pronounced and the blood pressure response to dipyridamole was less pronounced in morbidly obese patients compared with nonobese control patients. In the 43 patients who underwent catheterization, stress MPI had a sensitivity of 95% and negative predictive value of 80%. Kaplan-Meier survival analysis at 1 year showed a significant difference in survival rate of 98.3% for normal MPI studies and 94.0% for abnormal MPI studies (P = .02). CONCLUSION: Diagnostic-quality single photon emission computed tomography imaging is feasible in the majority (98%) of morbidly obese patients with the use of a dual-head camera, attenuation correction, and high stress Tc-99m tracer doses. Exercise stress was associated with better image quality. The prognostic value of a normal MPI study in this population appears to be less favorable than in non-morbidly obese patients.

Cohort Studies↗
PubMedDate not supplied

Effect of hormone replacement therapy on the electrocardiographic response to exercise.

BACKGROUND: Female gender and hormonal status affect electrocardiographic (ECG) response to exercise. Both are often cited as factors contributing to the decreased diagnostic accuracy of exercise stress tests in women. However, there is a paucity of data. To explore the relationship between hormonal status and exercise-induced ECG changes, we used gated single photon emission computed tomography (SPECT) technetium 99m sestamibi imaging for detection of myocardial ischemia. METHODS AND RESULTS: ECG response to exercise was analyzed in all female patients who underwent symptom-limited exercise stress testing over a 12-month period with no evidence of ischemia on SPECT myocardial perfusion imaging (N = 404). Hormonal status was defined as premenopausal (n = 78), postmenopausal (n = 277), and postmenopausal on hormone replacement therapy (HRT) (n = 49). Positive ECG response for ischemia was defined as 1 mm or greater horizontal and/or downsloping ST depression during and/or after exercise. The frequency of a positive ECG response to exercise without evidence of ischemia on gated SPECT imaging was analyzed according to hormonal status. Seventeen of 78 premenopausal women (22%), 48 of 277 postmenopausal women (17%), and 19 of 49 women taking HRT (39%) had a positive ECG response. ECG positivity was significantly higher in HRT users when compared with premenopausal (P =.05) and postmenopausal women (P =.001). CONCLUSIONS: Exogenous estrogen replacement therapy affects ST-segment response to exercise, likely through a nonischemic mechanism. Unless HRT can be discontinued for a prolonged period of time (up to 6 weeks) prior to a stress test, myocardial imaging should be used to improve diagnostic accuracy.

Adult↗