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D S Bach

Publications and source records attributed to D S Bach.

At least 55 records · Page 3Linked to original sources
PubMed1996

Quantitative Doppler tissue imaging as a correlate of left ventricular contractility.

Doppler tissue imaging is a new noninvasive imaging modality that allows quantitation of the low intensity, high amplitude Doppler shifts in the range of myocardial tissue motion. This study was performed to test the hypothesis that Doppler tissue imaging may provide unique information reflecting left ventricular systolic function, and to test the relationship between myocardial tissue velocity and noninvasive measures of ventricular contractility. Nine patients with mild or moderate mitral insufficiency and no regional wall motion abnormality were studied during dobutamine stress echocardiography. Left ventricular ejection fraction and peak systolic velocity of the sub-endocardial left ventricular posterior wall were quantified at baseline and at peak stress and compared with estimated peak dP/dt. During dobutamine infusion, ejection fraction increased from 41.7 +/- 22.2 (range 14 to 70) % to 56.6 +/- 27.9 (range 17 to 84)% (p = 0.001), peak systolic velocity increased from 22.7 +/- 4.2 (range 18 to 28) mm/sec to 35.3 +/- 10.1 (range 20 to 47) mm/sec (p = 0.004), and dP/dt increased from 1050 +/- 322 (range 613 to 1574) mm Hg/sec to 1766 +/- 768 (range 936 to 3000) mm Hg/sec (p = 0.01). Although there were good correlations between left ventricular dP/dt and both ejection fraction (R = 0.75) and peak systolic velocity (R = 0.81), the correlation between change in dP/dt and change in myocardial velocity (R = 0.75) was better than that between change in dP/dt and change in ejection fraction (R = 0.36). These data support the hypothesis that myocardial velocity determined with Doppler tissue imaging reflects myocardial contractility, and that catecholamine-induced alteration in contractility is better reflected by changes in myocardial velocity than by changes in ejection fraction.

Adult↗
PubMed1996

Quantitative Doppler tissue imaging for assessment of regional myocardial velocities during transient ischemia and reperfusion.

Doppler tissue imaging (DTI) is a new noninvasive imaging modality that directly interrogates myocardial velocity with high temporal and spatial resolution. This study was designed to test the hypothesis that quantitative DTI provides unique information regarding regional myocardial systolic and diastolic function during acute ischemic events. Myocardial velocities were quantified during the acute ischemic and reperfusion phases of 13 elective percutaneous coronary angioplasty procedures in 12 patients. In myocardium subtended by angioplasty vessels, peak velocities decreased during occlusive balloon inflation (from 21.2 +/- 9.8 to -0.6 +/- 4.0 mm/sec in systole [p < 0.001] and from 21.7 +/- 9.2 to -0.6 +/- 3.9 mm/sec in diastole [p < 0.001]). During early reperfusion, velocities exceeded those observed at baseline (p = 0.003). In regions remote from the treated artery, peak myocardial velocities increased in the absence of significant stenosis but remained unchanged or decreased in the presence of significant stenosis of the associated vessel. We conclude that (1) myocardial velocities rapidly decrease during acute ischemia and show a rebound increase after reperfusion, and (2) in regions remote from ischemia, velocities display distinct patterns on the basis of the presence or absence of obstructive coronary disease in the associated vessel. Quantitative DTI is a useful tool for the assessment of myocardial velocity and may provide new insights into myocardial systolic and diastolic function.

Angioplasty, Balloon, Coronary↗
PubMed1996

Mitral valve reconstruction in elderly, ischemic patients.

The role of mitral valve reconstruction is controversial in elderly patients with concurrent ischemic heart disease owing to technical difficulty, prolonged operative times, high mortality, and possible residual mitral regurgitation. However, mitral reconstruction could be most beneficial in this age group due to preservation of left ventricular function, avoidance of anticoagulation, or repeat operation for bioprosthetic degeneration. We studied the outcome of mitral valve reconstruction in 100 consecutive elderly ischemic patients 65 years or older (mean = 73 years; range, 65 to 86 years) operated on between October 1990 and May 1995. Preoperatively all patients were New York Heart Association (NYHA) class III or IV with an ejection fraction of 32 +/- 2%. All patients underwent primary coronary bypass grafting (2.7 +/- 0.2 grafts) and had a flexible mitral annuloplasty ring inserted. Additionally, 54 patients required further complex mitral repairs. All patients had 4+ mitral regurgitation by transesophageal echocardiography prior to operation. After mitral reconstruction, no patient had more than 1+ regurgitation, while most had none and no systolic anterior leaflet motion was noted. There were 4 early (30 day) deaths (4%) and 6 late deaths (6%) at a mean follow-up of 25 months. Patient morbidity has included episodes of mild congestive heart failure (nine), transient ischemic attack (one), endocarditis (one), and respiratory failure (five). There have been one early and two late reoperations for mitral valve replacement. All remaining patients are in NYHA class I or II. While longer-term follow-up is mandatory, coronary bypass grafting and mitral valve reconstruction in the elderly can be accomplished with acceptable surgical mortality and morbidity, yielding reliable improvement in symptoms and quality of life.

Aged↗
PubMed1996

Familial association of primary pulmonary hypertension and a new low-oxygen affinity beta-chain hemoglobinopathy, Hb Washtenaw.

A Hungarian-American kindred with familial primary pulmonary hypertension (PPH) and a new, low-oxygen affinity beta-chain variant hemoglobin, Hb Washtenaw, is described. The index case presented with severe PPH and was found to have the abnormal hemoglobin. Two siblings with the abnormal hemoglobin also demonstrated increased pulmonary artery pressures on exercise echocardiography suggestive of early PPH. The occurrence of PPH and the abnormal hemoglobin could be due to genetic or biochemical factors or simply coincidental. A previous study had described a possible association of an abnormal beta-chain variant hemoglobin, Hb Warsaw, and PPH. It was suggested that the putative gene for familial PPH may be located near the beta-globin gene on chromosome 11. The association of PPH and the beta-chain variant hemoglobin in this kindred adds further support to this hypothesis.

Base Sequence↗
PubMed1995

Arbutamine echocardiography: efficacy and safety of a new pharmacologic stress agent to induce myocardial ischemia and detect coronary artery disease. The International Arbutamine Study Group.

OBJECTIVES: This study sought to determine the efficacy and safety of arbutamine echocardiography in inducing myocardial ischemia and detecting coronary artery disease. BACKGROUND: Exercise and pharmacologic stress echocardiography are clinically accepted techniques for detecting coronary artery disease. Arbutamine is a new synthetic beta-adrenoceptor agonist developed specifically as a stress agent. Arbutamine is delivered by a new computerized drug delivery device that adjusts the rate of drug infusion according to the patient's heart rate response during stress testing. METHODS: The sensitivity of arbutamine echocardiography was determined in 143 patients who had coronary artery disease documented by coronary angiography. A subset of these patients (n = 114) also underwent exercise echocardiography. The specificity, or normalcy, of arbutamine echocardiography was determined in 54 patients considered to have a low likelihood of coronary artery disease. RESULTS: Among those patients who had both stress test results, the incidence of inducing myocardial ischemia (new or worsening wall motion abnormalities) was 79% (95% confidence interval [CI] 69% to 86%, n = 98) for arbutamine and 77% (95% CI 67% to 85%, n = 98) for exercise echocardiography. The sensitivity of detecting coronary artery disease (ischemia or rest wall motion abnormality) was 87% (95% CI 79% to 93%, n = 101) for arbutamine and 83% (95% CI 74% to 90%, n = 101) for exercise echocardiography. The specificity (normalcy) of arbutamine echocardiogrpahy was 96% (95% CI 87% to 100%, n = 52). Arbutamine was well tolerated, and there were no serious adverse events. CONCLUSIONS: Arbutamine echocardiography is an effective and safe pharmacologic stress test technique for diagnosing or excluding the presence of coronary artery disease. The ability of arbutamine stress to induce myocardial ischemia, detectable by echocardiography, was comparable to that for exercise.

Cardiotonic Agents↗
PubMed1995

Accuracy of intraoperative transesophageal echocardiography for estimating the severity of functional mitral regurgitation.

Although intraoperative transesophageal echocardiography (TEE) is used to guide mitral valve reconstructive procedures, the effects of hemodynamic alterations accompanying general anesthesia on mitral regurgitation (MR) are unknown. This study was performed to evaluate the effect of general anesthesia on MR jet size using TEE with color Doppler imaging in patients undergoing mitral valve surgery. Matched preoperative TEEs performed with the patient under intravenous conscious sedation, and intraoperative studies performed with the patient under general anesthesia were retrospectively reviewed in 46 patients undergoing mitral valve surgery. Patients were divided into groups based on etiology of MR, including 21 patients with myxomatous degeneration and leaflet flail, 19 patients with structurally normal leaflets and functional regurgitation due to abnormal leaflet coaptation, and 6 patients with rheumatic mitral disease. On both preoperative and intraoperative studies, regurgitation was quantified using maximal jet area and jet diameter at the vena contracta on color flow Doppler. Patients with leaflet flail and patients with functional MR had similar measures of regurgitation severity on preoperative imaging. On intraoperative imaging, regurgitant jet size was unchanged compared with preoperative studies among patients with leaflet flail (jet diameter 1.04 +/- 0.26 vs 1.10 +/- 0.28 cm, area 9.8 +/- 4.5 vs 10.1 +/- 5.2 cm2 on preoperative studies), although jet size decreased significantly in patients with functional MR (jet diameter 0.79 +/- 0.33 vs 1.10 +/- 0.29 cm [p < 0.001], area 5.7 +/- 3.5 vs 10.0 +/- 3.8 cm2 [p < 0.001] on preoperative studies). These findings were not accounted for by variation in heart rate, blood pressures, echocardiographic instrumentation, or Doppler Nyquist limit.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1995

Adequacy of low-stress arbutamine to provoke myocardial ischemia during echocardiography. International Arbutamine Study Group.

Arbutamine is a new, potent, short-acting synthetic catecholamine developed specifically for use as a cardiac stress agent. Previous reports on the accuracy of arbutamine for the detection of coronary artery disease have relied on heart rate (HR) increases similar to those seen at peak exercise. This study was undertaken to test the potential to provoke ischemic wall motion abnormalities on echocardiography using arbutamine at a HR below that associated with peak exercise. One hundred forty-six patients with coronary artery disease underwent computerized closed-loop stress testing with arbutamine; 120 (82%) had echocardiographic images adequate for analysis at baseline, low stress (20 beats/min above baseline), and peak stress (target of 85% age-predicted peak HR). Ejection fraction increased from 59 +/- 10% at baseline to 72 +/- 12% at low stress, and remained stable at 72 +/- 14% at peak stress. Of 88 patients with echocardiographic evidence of ischemia at peak stress, 73 (83%) had evidence of ischemia at low stress. Change in wall motion score index from baseline to low stress represented 62% of the change noted from baseline to peak stress. A greater number of stenotic vessels were associated with a somewhat higher proportion of ischemic responses evident at low stress. The present study suggests that the maximal inotropic effects of arbutamine may occur at a dose lower than that required for maximal chronotropic effect. In the future, it may be possible to establish an infusion end point for arbutamine stress testing using a HR < 85% of the age-predicted maximum.

Adult↗
PubMed1995

Regional heterogeneity on myocardial contrast echocardiography without severe obstructive coronary artery disease.

Myocardial contrast echocardiography (MCE) has been used successfully during cardiac catheterization to assess regional perfusion in patients with coronary artery disease (CAD), although heterogeneity on MCE has been observed without underlying CAD. This study was undertaken to assess regional perfusion patterns on visual assessment of MCE when interpreted without knowledge of coronary anatomy, and to define potential sources of contrast heterogeneity not related to underlying CAD. Forty patients underwent intracoronary or aortic root MCE, or both, with use of 5% sonicated human serum albumin (Albunex) at the time of left heart catheterization. A single observer without knowledge of angiographic coronary anatomy reviewed all contrast echocardiographic studies for evidence of heterogeneous or collateral-dependent perfusion that was believed to be predictive of CAD. Of 110 vessels with paired echocardiographic and quantitative coronary angiographic data, 10 had lesions with > 70% luminal diameter stenosis and 6 of these were occluded. Of 100 vessels without significant stenosis, blinded analysis of MCE identified 36 regions with abnormal contrast considered predictive of CAD (false-positive results). False-positive studies occurred most often (incidence 46%) in the distribution of the left circumflex artery. Myocardial contrast in a coronary perfusion territory was completely absent after > or = 1 injection in 56 of 100 vessels without significant disease, although contrast was visualized on a subsequent injection in 51 of 56 vessels (91%). The low prevalence of disease among the population studied precluded meaningful estimation of test sensitivity for the detection of CAD. However, regional contrast heterogeneity was frequently observed on MCE in the absence of CAD.(ABSTRACT TRUNCATED AT 250 WORDS)

Albumins↗
PubMed1995

Quantitative Doppler tissue imaging of the left ventricular myocardium: validation in normal subjects.

Doppler tissue imaging (DTI) is a new echocardiographic imaging technique from which quantitative data regarding myocardial velocity can be extracted. The purpose of this study was to compare endocardial velocities determined from DTI with those determined from M-mode echocardiography and to assess the range of myocardial velocities in normal subjects. Nineteen subjects were evaluated by M-mode echocardiography and quantitative DTI for maximal systolic velocities of the anteroseptal and inferoposterior walls. Mid-myocardial and epicardial velocities were also measured by DTI for each wall. Maximal systolic velocities of the anteroseptal and inferoposterior endocardium determined by DTI correlated significantly with those derived from M-mode echocardiography (r = 0.87). The velocity of the inferoposterior wall by DTI (27.3 +/- 4.8 mm/sec) was greater than that of the anteroseptum (20.8 +/- 4.1 mm/sec) by a mean difference of 7.0 +/- 5.7 mm/sec (p < 0.001). A peak velocity gradient of 5.9 +/- 3.5 mm/sec (p < 0.001) between the epicardium to endocardium was detected. These data confirm that (1) regional myocardial velocities may be quantified with DTI in human beings; (2) the high resolution of DTI allows velocities to be determined at different levels within the myocardium; and (3) heterogeneity of myocardial velocities may be demonstrated in normal subjects.

Adult↗
PubMed1995

Early improvement in congestive heart failure after correction of secondary mitral regurgitation in end-stage cardiomyopathy.

Mitral regurgitation frequently complicates dilated cardiomyopathy, aggravates volume overload of the left ventricle, and contributes to symptoms of congestive heart failure. This study was performed to assess the impact of mitral valve reconstruction in nine consecutive patients with severe mitral regurgitation resulting from end-stage dilated cardiomyopathy. Clinical and echocardiographic follow-up were obtained 17 +/- 5 and 16 +/- 6 weeks after surgery, respectively. There were no operative or early deaths. All patients noted symptomatic improvement postoperatively, and there was a decrease of at least one New York Heart Association functional class (3.9 +/- 0.3 to 1.7 +/- 0.5, p < 0.001). Quantitative echocardiography/Doppler demonstrated a small but significant decrease in left ventricular end-diastolic volume (317 +/- 111 ml to 291 +/- 105 ml, p = 0.04) and increases in ejection fraction (18 +/- 5% to 24 +/- 9%, p = 0.02) and forward cardiac output (3.1 +/- 1.0 to 4.6 +/- 0.8 L/min, p < 0.01) on follow-up. Mitral valve reconstruction for the correction of mitral regurgitation in patients with end-stage dilated cardiomyopathy results in improved symptomatic status on early follow-up accompanied by evidence of improvement in left ventricular performance.

Adult↗
PubMed1995

Heterogeneity of ventricular function and myocardial oxidative metabolism in nonischemic dilated cardiomyopathy.

OBJECTIVES: This study was performed to test the hypothesis that regional variation in ventricular function in patients with nonischemic dilated cardiomyopathy is related to regional variation in oxidative metabolism. BACKGROUND: Heterogeneity in regional left ventricular function has long been noted in patients with nonischemic dilated cardiomyopathy. Regional variation in wall stress has been proposed as the pathophysiologic mechanism. By correlating regional function with oxidative metabolism, one can test the hypothesis that heterogeneity in wall stress is responsible for heterogeneity in function. We hypothesized that preserved function as a result of more favorable loading conditions would be associated with regional oxidative metabolism that is equal to or lower than that in other regions. METHODS: Fifteen patients with nonischemic dilated cardiomyopathy (mean [+/- SD] ejection fraction 20.7 +/- 4.0%) were studied. Regional ventricular function was determined using short-axis chordal shortening on two-dimensional echocardiography. Regional oxidative metabolism was assessed by carbon-11 acetate clearance kinetics on dynamic positron emission tomography. An eight-segment model of the left ventricle was used. Segmental function and oxidative metabolism were defined as increased if they varied at least 1 SD from the respective mean value for that patient. RESULTS: Thirteen (87%) of 15 patients exhibited segments with increased function. In 7 (54%) of 13 patients, regional function was increased in the proximal lateral wall. Multivariate linear regression analysis showed a direct relation between regional function and oxidative metabolism (p = 0.02). The average concordance between increased function and increased oxidative metabolism among patients was 0.87 +/- 0.11 (95% confidence interval 0.70 to 1.00). CONCLUSIONS: Patients with nonischemic dilated cardiomyopathy display heterogeneity in regional ventricular function. Relative preservation is observed most frequently in the proximal lateral wall. Relative preservation of function is associated with higher regional oxidative metabolism, suggesting that mechanisms other than or in addition to local loading conditions may be responsible for heterogeneity in function.

Acetates↗
PubMed1995

Early outcome of mitral valve reconstruction in patients with end-stage cardiomyopathy.

Uncontrollable severe mitral regurgitation is a frequent complication of end-stage cardiomyopathy, significantly contributing to heart failure in these patients, and predicts a poor survival. Although elimination of mitral valve regurgitation could be most beneficial in this group, corrective mitral valve surgery has not been routinely undertaken in these very ill patients because of the presumed prohibitive operative mortality. We studied the early outcome of mitral valve reconstruction in 16 consecutive patients with cardiomyopathy and severe, refractory mitral regurgitation operated on between June 1993 and April 1994. There were 11 men and five women, aged 44 to 78 years (64 +/- 8 years) with left ventricular ejection fractions of 9% to 25% (16% +/- 5%). Preoperatively all patients were in New York Heart Association class IV, had severe mitral regurgitation (graded 0 to 4+ according to color flow Doppler transesophageal echocardiography) and two were listed for transplantation. Operatively, a flexible annuloplasty ring was implanted in all patients. Four patients also had single coronary bypass grafting for incidental coronary disease. In four patients the operation was performed through a right thoracotomy because of prior coronary bypass grafting, and four patients also underwent tricuspid valve reconstruction for severe tricuspid regurgitation. No patient required support with an intraaortic balloon pump. There were no operative or hospital deaths and mean hospital stay was 10 days. There were three late deaths at 2, 6, and 7 months after mitral valve reconstruction, and the 1-year actuarial survival has been 75%. At a mean follow-up of 8 months, all remaining patients are in New York Heart Association class I or II, with a mean postoperative ejection fraction of 25% +/- 10%. There have been no hospitalizations for congestive heart failure, and a decrease in medications required has been noted. For patients with cardiomyopathy and severe mitral regurgitation, mitral valve reconstruction as opposed to replacement can be accomplished with low operative and early mortality. Although longer term follow-up is mandatory, mitral valve reconstruction may allow new strategies for patients with end-stage cardiomyopathy and severe mitral regurgitation, yielding improvement in symptomatic status and survival.

Adult↗
PubMed1995

Clinical and diagnostic utility of arbutamine for cardiovascular stress testing during echocardiographic monitoring.

Arbutamine (Gensia, Inc., San Diego, CA) is a newly-developed sympathomimetic agent specifically designed for cardiovascular stress testing. It has been successfully used for the detection of coronary artery disease in conjunction with electrocardiography, echocardiographic and radionuclide techniques. Arbutamine increases heart rate and contractility, thus provoking ischaemia in a manner analogous to that of physical exercise. Ischaemia becomes manifest by reproduction of typical angina, diagnostic electrocardiographic changes, the development of a wall motion abnormality on two-dimensional echocardiography or of a perfusion defect on thallium scintigraphy. Thus far in clinical trials it has shown an acceptable side-effect profile and a level of diagnostic accuracy for the detection of patients with coronary disease equivalent to or exceeding that seen with physical exercise.

Cardiotonic Agents↗
PubMed1994

False positive dobutamine stress echocardiograms: characterization of clinical, echocardiographic and angiographic findings.

OBJECTIVES: This study was designed to characterize the clinical, echocardiographic and angiographic findings in patients who have regional wall motion abnormalities predictive of coronary artery disease on dobutamine stress echocardiograms, although coronary angiography reveals no critical stenoses. BACKGROUND: The specificity of dobutamine stress echocardiography has been reported to be lower than its sensitivity; the sources of false positive findings on dobutamine stress echocardiograms have not been previously defined. METHODS: Clinical and echocardiographic characteristics were retrospectively reviewed for patients who had both a dobutamine stress echocardiogram indicative of coronary artery disease on the basis of wall motion abnormalities and < 50% stenoses reported on coronary angiography performed within 6 weeks of the echocardiogram. A 16-segment model was used to perform wall motion scoring. Angiograms were independently reviewed, and stenosis severity was quantified with the use of digital calipers. RESULTS: Thirty-nine (11.4%) of 342 studies met criteria for false positive test results, which occurred predominantly in women (72%, p < 0.001). Regional wall motion abnormalities were evident more often in the posterior circulation (62%), and 65% of them were limited to the basal segments. Twelve (28%) of 43 wall motion abnormalities were associated with coronary stenoses of at least intermediate grade (lumen diameter 40.3% to 68.1%). Abnormalities confined to basal segments of the posterior circulation were unlikely to have associated coronary lesions (p = 0.03). CONCLUSIONS: False positive findings on dobutamine stress echocardiograms tend to involve small wall motion abnormalities that are frequently located in basal segments of the posterior myocardial circulation. Approximately one third of false positive results occurred in patients with intermediate-grade coronary stenoses, and these studies may reflect true inducible ischemia. Additional sources of false positive study results may include poor endocardial visualization and abnormal motion due to tethering to the fibrous skeleton of the heart. Altered echocardiographic diagnostic criteria may be appropriate for small wall motion abnormalities confined to basal segments of the posterior circulation.

Adult↗
PubMed1993

Acute effects of dobutamine on myocardial oxygen consumption and cardiac efficiency measured using carbon-11 acetate kinetics in patients with dilated cardiomyopathy.

OBJECTIVES: The aim of this study was to use positron emission tomography (PET)-derived carbon (C)-11 acetate kinetics to determine the effects of dobutamine on oxidative metabolism and its effects on myocardial efficiency in a group of patients with dilated cardiomyopathy. BACKGROUND: Dobutamine is known to improve myocardial function but may do so at the expense of myocardial oxygen consumption, which could be a potential deleterious effect. Carbon-11 acetate kinetics correlate with myocardial oxygen consumption as shown in animal models. Combining these scintigraphic measurements of oxygen consumption with estimates of cardiac work results in a work-metabolic index, which reflects cardiac efficiency. METHODS: Eight patients with nonischemic dilated cardiomyopathy underwent dynamic PET imaging, echocardiography and hemodynamic measurements. Seven of these patients were also studied while receiving dobutamine. Direct measurements of myocardial oxygen consumption using coronary sinus catheterization were obtained with eight of the PET studies to validate C-11 acetate in patients with cardiomyopathy. RESULTS: The mean (+/- SD) C-11 clearance rate significantly increased with dobutamine from 0.105 +/- 0.027 to 0.155 +/- 0.023 min-1 (p = 0.001). Directly measured myocardial oxygen consumption had a linear relation to the mean C-11 clearance rate (r = 0.8, p = 0.018). Dobutamine was noted to significantly reduce systemic vascular resistance as well as the severity of mitral regurgitation. The work-metabolic index determined using hemodynamic variables and PET data increased from 2 +/- 0.7 x 10(4) to 2.6 +/- 0.6 x 10(4) (p = 0.04). Efficiency, estimated by employing the oxygen consumption to k2 relation, also increased from 13 +/- 4.5% to 16.9 +/- 6.4% (p = 0.04). CONCLUSIONS: Despite an increase in myocardial oxygen consumption, dobutamine led to an increase in work-metabolic index in patients with dilated nonischemic cardiomyopathy. Dobutamine reduced systemic vascular resistance and mitral regurgitation, suggesting that in this group of patients, it had important vasodilatory action in addition to its inotropic effects. The use of the C-11 acetate PET for determining myocardial oxygen consumption and estimating efficiency could potentially complement existing clinical measures of ventricular performance and may allow improved and objective evaluation of therapy in patients with heart failure.

Adult↗
PubMed1993

Dobutamine stress echocardiography: prevalence of a nonischemic response in a low-risk population.

The problems of population referral bias in the calculation of specificity in diagnostic testing for coronary artery disease have been previously described. Previous studies investigating the sensitivity and specificity of dobutamine stress echocardiography (DSE) have been subject to pretest and posttest referral biases, largely as a result of the requirement for coronary arteriography. This study determines the normalcy rate for DSE by examining a population at statistically low risk for coronary artery disease. The probability of significant coronary artery disease was determined for 828 consecutive patients referred for DSE at the University of Michigan, and groups were identified with < 10% and < 5% probability of disease. Four of 72 patients (5.6%) with a normal baseline echocardiogram and a probability of coronary artery disease of < 10%, and three of 38 (7.9%) with a probability of < 5% were found to have an abnormal DSE, yielding normalcy rates of 94.4% and 92.1%, respectively. The area of abnormality involved the posterior circulation in three of four patients (75%). This study demonstrates that DSE has a normalcy rate of 92% to 94% and is an accurate test for excluding the presence of significant coronary artery disease.

Adult↗