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Don Poldermans

Publications and source records attributed to Don Poldermans.

At least 145 records · Page 8Linked to original sources
PubMed2003

Dobutamine-induced contractile reserve in stunned, hibernating, and scarred myocardium in patients with ischemic cardiomyopathy.

UNLABELLED: Because of damage to cardiomyocytes and the contractile apparatus, contractile reserve may be observed less frequently in hibernating than in stunned myocardium. The aim of this study was to assess the presence of contractile reserve in response to dobutamine infusion in a large group of patients with stunned and hibernating myocardium. METHODS: A total of 198 consecutive patients with ischemic cardiomyopathy (left ventricular ejection fraction < or = 40%) underwent resting 2-dimensional echocardiography to assess regional contractile dysfunction. On the basis of assessment of perfusion (with (99m)Tc-tetrofosmin SPECT) and glucose use (with (18)F-FDG SPECT), dysfunctional segments were grouped. Dysfunctional segments with normal perfusion were classified as stunned. Dysfunctional segments with a perfusion defect were classified as hibernating when a perfusion-(18)F-FDG mismatch was present. Dysfunctional segments with a perfusion defect were classified as scar tissue when a perfusion-(18)F-FDG match was present; these segments were subdivided into nontransmural and transmural scars. Contractile reserve was evaluated by dobutamine stress echocardiography. RESULTS: Dobutamine-induced contractile reserve was more frequently found in stunned than in hibernating myocardium (61% vs. 51%, respectively; P < 0.01). Only 14% of the scarred segments improved in wall motion during dobutamine infusion, significantly less than stunned or hibernating myocardium (P < 0.001). Nontransmural scars exhibited contractile reserve more frequently than did transmural scars. CONCLUSION: The progressive reduction of contractile reserve in stunned, hibernating, and scarred myocardium supports the hypothesis that stunning, hibernation, and scarring are not circumscript pathophysiologic entities but represent gradual ultrastructural damage on the myocyte level.

Dobutamine↗
PubMed2003

Feasibility and image quality of dual-isotope SPECT using 18F-FDG and (99m)Tc-tetrofosmin after acipimox administration.

UNLABELLED: Currently, with the rapidly increasing number of patients with heart failure due to chronic coronary artery disease, the need for viability studies to guide treatment in these patients is increasing. The most accurate method for viability assessment is metabolic imaging with (18)F-FDG with PET or SPECT. To obtain excellent image quality in all patients, the (18)F-FDG studies should be performed during hyperinsulinemic euglycemic clamping. However, this approach is time-consuming and is not feasible in busy nuclear medicine laboratories. Recently, the use of a nicotinic acid derivative, acipimox, has been suggested, but limited data are available on the image quality of the (18)F-FDG studies using this approach. METHODS: We evaluated the feasibility and image quality of (18)F-FDG SPECT (with dual-isotope simultaneous acquisition (DISA) using (99m)Tc-tetrofosmin to assess perfusion) after acipimox administration in 50 nondiabetic patients. The image quality of both (18)F-FDG and (99m)Tc-tetrofosmin was assessed visually and quantitatively using myocardium-to-blood-pool (M/B) ratios as a measure of target-to-background ratio. The image quality and diagnostic value of DISA (99m)Tc-tetrofosmin SPECT was compared with standard (99m)Tc-tetrofosmin SPECT at baseline. RESULTS: After acipimox administration, the plasma levels of free fatty acids were extremely low (68 +/- 89 nmol/L). No severe side effects were observed, only paroxysmal flushing. The (18)F-FDG image quality was good in 46 patients (92%) and moderate but still interpretable in the other 4 patients (8%). The clinical information of the baseline (99m)Tc-tetrofosmin SPECT was retained in the DISA (99m)Tc-tetrofosmin SPECT images because we did observe no substantial fill-in of perfusion defects by high (18)F-FDG uptake in the same segment. CONCLUSION: Cardiac (18)F-FDG SPECT after acipimox is safe and resulted consistently in good image quality; this simple approach may be the method of choice for routine cardiac metabolic imaging.

Administration, Oral↗
PubMed2003

Effect of diabetes mellitus on myocardial 18F-FDG SPECT using acipimox for the assessment of myocardial viability.

UNLABELLED: During the noninvasive assessment of myocardial viability with (18)F-FDG metabolic imaging, adequate regulation of metabolic conditions is needed to ensure optimal image quality. The aim of this study was to compare the feasibility and image quality of cardiac (18)F-FDG SPECT imaging using acipimox in patients with diabetes and patients without diabetes. METHODS: Seventy patients with ischemic cardiomyopathy underwent (18)F-FDG SPECT using acipimox for the assessment of myocardial viability, followed by resting 2-dimensional echocardiography to identify dysfunctional myocardial tissue. The image quality was scored visually and quantitatively; the myocardium-to-background ratio was determined by region-of-interest analysis. The plasma concentrations of glucose and free fatty acids were determined to evaluate the metabolic conditions before and during (18)F-FDG imaging. RESULTS: Thirty-four patients had diabetes mellitus; of these, 12 had insulin-dependent diabetes mellitus and 22 had non-insulin-dependent diabetes mellitus. The remaining 36 patients had no diabetes. During (18)F-FDG SPECT, no severe side effects occurred. Acipimox significantly lowered plasma levels of free fatty acids in both groups. Fifteen of 34 patients with diabetes had a plasma glucose level > 9 mmol/L, which was lowered successfully in all patients with additional insulin. Visual evaluation of the (18)F-FDG images showed good, moderate, and poor image quality in 27, 5, and 2 patients, respectively, with diabetes mellitus and in 32, 4, and 0 patients, respectively, without diabetes (P = not statistically significant). The myocardium-to-background ratio of (18)F-FDG SPECT images was comparable in patients with and without diabetes mellitus (3.1 +/- 1.0 vs. 3.5 +/- 0.9, P = not statistically significant). The type of diabetes had no influence on (18)F-FDG image quality. CONCLUSION: (18)F-FDG SPECT metabolic imaging after acipimox is safe and practical for routine assessment of viability in patients with ischemic cardiomyopathy. Image quality is good, even in patients with diabetes, although additional insulin is sometimes needed.

Blood Glucose↗
PubMed2003

Safety of dobutamine stress echocardiography in patients with aortic stenosis.

BACKGROUND AND AIM OF THE STUDY: Aortic valve disease is becoming one of the most important cardiac diseases in western society. Low-dose dobutamine stress echocardiography (DSE) is recommended in patients with low-gradient aortic stenosis (AS) and severe left ventricular (LV) dysfunction. DSE is also used in patients with AS and moderately reduced or normal LV function for diagnostic purposes. The study aim was to assess the safety of DSE in the setting of AS and various degrees of LV dysfunction. METHODS: A total of 75 patients with AS who underwent DSE at the authors' center between 1997 and 2001 was reviewed. Group A patients (n = 20) had severely reduced mean LV ejection fraction (LVEF) of 25 +/- 6% and underwent low-dose DSE; group B patients (n = 55) had moderate to normal LV function (LVEF 51 +/- 8%) and underwent high-dose DSE. The mean pressure gradient, valve area and side effects after DSE were evaluated. RESULTS: Serious cardiac arrhythmias occurred in 10 patients. In group A, four patients (20%) developed non-sustained ventricular tachycardia. In group B, two patients (4%) had non-sustained ventricular tachycardia (VT), four (7%) had paroxysmal supraventricular tachycardias, and two (4%) severe symptomatic hypotension. Among the 20 patients with evidence of ischemia on DSE, three developed adverse side effects (no difference compared with patients without ischemia; p = 0.922). Fourteen patients received atropine during DSE, and 1 of these developed non-sustained VT after atropine administration. CONCLUSION: Serious cardiac arrhythmias occur frequently during both low-dose and high-dose DSE in patients with AS. Adverse side effects do not relate to stress-induced ischemia or atropine addition.

Adrenergic beta-Agonists↗
PubMed2002

Perfusion and contractile reserve in chronic dysfunctional myocardium: relation to functional outcome after surgical revascularization.

BACKGROUND: Chronic dysfunctional but viable myocardium may exhibit contractile reserve and/or intact perfusion. Segments with intact perfusion without contractile reserve are frequently observed inpatients with ischemic cardiomyopathy. The clinical relevance of this observation is unclear; in particular, the functional outcome after revascularization is unknown. Thus, contractile reserve (using low-dose dobutamine echocardiography) and perfusion (using resting (99m)Tc tetrofosmin) were evaluated in 114 patients with ischemic cardiomyopathy and the findings were related to functional outcome (9 to 12 months after revascularization). METHODS AND RESULTS: Patients (n=114) with ischemic cardiomyopathy undergoing surgical revascularization were evaluated for perfusion (using (99m)Tc tetrofosmin) and contractile reserve (using low-dose dobutamine echocardiography). Contractile function (two-dimensional echocardiography) was assessed before and 9 to 12 months after revascularization. In the 1 336 dysfunctional segments, perfusion was preserved in 51% of the segments and contractile reserve in 31% (P<.05); 47% of the segments with perfusion did not exhibit contractile reserve. The majority (66%) of segments with recovery of function postrevascularization had intact perfusion and contractile reserve; the majority (58%) of segments without functional recovery lacked both perfusion and contractile reserve. Interestingly, 22% of segments with functional recovery and 25% of segments without functional recovery showed intact perfusion without contractile reserve. CONCLUSION: Segments with intact perfusion/contractile reserve have a high likelihood of recovery of function postrevascularization; segments without contractile reserve/perfusion have a low likelihood of recovery and segments with intact perfusion without contractile reserve have an intermediate likelihood of recovery.

Angina Pectoris↗
PubMed2002

Assessment of viable tissue in Q-wave regions by metabolic imaging using single-photon emission computed tomography in ischemic cardiomyopathy.

Chronic electrocardiographic Q waves are often believed to reflect irreversibly scarred, transmurally infarcted myocardium. The aim of this study was to evaluate whether residual viable tissue persists in dysfunctional myocardial regions related to chronic Q waves on the surface electrocardiogram. A total of 148 patients with healed myocardial infarction and impaired left ventricular (LV) function with heart failure symptoms underwent electrocardiography and metabolic imaging using technetium (Tc-99m) tetrofosmin/F18-fluorodeoxyglucose (FDG) single-photon emission computed tomography (SPECT). The left ventricle was divided into 4 major regions to compare myocardial viability in regions with and without chronic Q waves on surface electrocardiography. According to FDG SPECT metabolic imaging, residual viable tissue persisted in a high proportion (61%) of dysfunctional myocardial regions with chronic Q waves. Regions with chronic Q waves were more often dysfunctional than regions without Q waves. Moreover, dysfunctional regions with chronic Q waves were less frequently viable compared with dysfunctional regions without Q waves on the electrocardiogram. This study demonstrates that chronic Q waves on electrocardiography do not necessarily imply irreversibly scarred myocardium. Residual viable tissue persists in a high proportion of dysfunctional ventricular regions according to FDG SPECT metabolic imaging.

Aged↗
PubMed2002

Prediction of mortality in heart transplant recipients by stress technetium-99m tetrofosmin myocardial perfusion imaging.

Cardiac allograft vasculopathy is a major cause of mortality in heart transplant recipients. The aim of this study was to assess the prognostic value of stress myocardial perfusion imaging in heart transplant recipients. We studied 166 patients (age 54 +/- 10 years, 140 men) by symptom-limited bicycle exercise or dobutamine (up to 40 microg/kg/min) stress myocardial perfusion imaging 7.4 +/- 2.5 years after heart transplantation. An intravenous dose of 370 MBq of technetium-99m tetrofosmin was injected at peak stress and 24 hours after the stress test. An abnormal test was defined as reversible or fixed perfusion defects. Perfusion abnormalities were detected in 55 patients (33%). During a median follow-up of 2.5 years, 54 deaths (33%) occurred, 16 of which were due to cardiac causes. The incidence of perfusion abnormalities was higher in patients with subsequent cardiac death than in patients without subsequent cardiac death (69% vs 29%, p = 0.01). In an incremental multivariate Cox analysis, cardiac death was not predicted by age, gender, duration of transplantation, number of rejection episodes, or cytomegalovirus infection. In the next step, stress test parameters were added. The peak rate-pressure product was the only significant predictor at this step (risk ratio 0.84, 95% confidence interval 0.73 to 0.97, chi-square 7.7, p = 0.006). In the final step, the presence of abnormal myocardial perfusion was an independent predictor of cardiac death (risk ratio 3.5, 95% confidence interval 1.6 to 11.7, chi-square 4.7, incremental to clinical and stress test variables, p = 0.01). It is concluded that stress myocardial perfusion imaging with technetium-99m tetrofosmin single-photon emission computed tomography provides incremental data for the prediction of cardiac death in heart transplant recipients.

Echocardiography, Stress↗
PubMed2002

Feasibility, safety and image quality of cardiac FDG studies during hyperinsulinaemic-euglycaemic clamping.

Fluorine-18 fluorodeoxyglucose (FDG) imaging for the assessment of myocardial viability has become an integral part of the diagnostic and prognostic work-up of patients with ischaemic cardiomyopathy. To ensure good image quality, in particular in patients with diabetes mellitus, hyperinsulinaemic-euglycaemic clamping has been proposed. In this study we evaluated the safety and the image quality of cardiac FDG imaging during clamping in a large group of patients, including a subgroup with diabetes mellitus. The incidence of viability (on both a segment and a patient basis) was also determined for patients with and without diabetes mellitus. The safety and image quality of cardiac FDG studies during clamping were evaluated in 131 patients, including 19 with diabetes mellitus. Image quality was assessed visually and quantitatively using heart-to-lung (H/L), heart-to-liver (H/Li) and myocardium-to-background (M/B) ratios. Blood samples were drawn at baseline and at the time of FDG injection to determine levels of glucose, free fatty acids and insulin. The metabolic circumstances were optimal for FDG imaging: high insulin levels, low free fatty acid levels and glucose levels in the normal range (levels of substrates were comparable between patients with and patients without diabetes mellitus). No serious side-effects occurred in any patient. Image quality (assessed visually) was good in all patients. The quantitative parameters of image quality (H/L, H/Li and M/B) were comparable between patients with and patients without diabetes mellitus. The incidence of viability was high: 38% of patients without and 58% of patients with diabetes mellitus had substantial viability despite contractile dysfunction. It is concluded that cardiac FDG imaging during clamping is safe and provides excellent image quality, including in patients with diabetes mellitus. The incidence of viability is high, in particular in patients with diabetes mellitus.

Aged↗
PubMed2002

Assessment of residual myocardial viability in regions with chronic electrocardiographic Q-wave infarction.

BACKGROUND: Q waves on the electrocardiogram are often considered to be reflective of irreversibly scarred myocardium due to antecedent transmural myocardial infarction. However, there are some indications that residual viable tissue may be present in Q-wave-infarcted regions. It is clinically relevant to know how many Q-wave regions contain viable tissue because these patients may benefit from revascularization in terms of improvement of function and long-term survival. METHODS: Patients (n = 150) with chronic electrocardiographic Q-wave infarction, heart failure symptoms, and chronic coronary artery disease underwent dobutamine-atropine stress echocardiography to assess myocardial viability. Residual viability in regions with Q-wave infarction was considered present when the end-diastolic wall thickness (EDWT) was >6 mm and the response during dobutamine infusion indicated viable tissue. RESULTS: Baseline echocardiography revealed 517 dysfunctional myocardial regions; 202 of the dysfunctional regions were related to Q waves on the electrocardiogram and the other 315 dysfunctional regions were not. EDWT was < or =6 mm in 13 regions with a Q wave on the electrocardiogram, with only 1 region exhibiting viable tissue during dobutamine stress echocardiography. EDWT was >6 mm in 189 regions with a Q wave, with 118 (62%) having viable tissue on dobutamine stress echocardiography. In 6 dysfunctional regions without a Q wave, EDWT was < or =6 mm, with all being nonviable on dobutamine stress echocardiography; of the 309 regions without a Q wave and EDWT >6 mm, 204 (66%) exhibited viability on dobutamine stress echocardiography. CONCLUSIONS: Fifty-eight percent of dysfunctional regions related to chronic Q waves were viable according to the combined information of EDWT and dobutamine stress echocardiography. EDWT </=6 mm virtually excludes viability; regions with EDWT >6 mm need additional testing to detect or exclude viability.

Cardiac Output, Low↗
PubMed2002

Experience with an ultrasound stethoscope.

BACKGROUND: To test the diagnostic potential of the SonoHeart, a battery-powered hand-held ultrasound imaging device, in an outpatient clinic setting. METHODS: A total of 114 patients with a variety of cardiac diseases were examined by 2 independent cardiologists with the hand-held device using the standard echocardiographic system (SE) as a reference. Global right ventricular (RV) and left ventricular (LV) function (scored as normal, mildly to moderately, or severely reduced) and internal cavity dimensions were assessed. Regional wall motion of 6 segments using a 2-point score (1 = normal wall motion, 2 = abnormal wall motion) was evaluated in 34 patients on-line. RESULTS: There was a good agreement between the 2 imaging devices for evaluation of global LV (93%) and RV function (99%), regional wall motion (90%), dimensions of the LV (99%) and the RV (99%), and the left (96%) and right atria (99%). Furthermore, SonoHeart identified hypertrophic cardiomyopathy, pericardial effusion, and abnormalities of valves. CONCLUSION: The SonoHeart device allows rapid and accurate diagnosis, whenever needed in the outpatient clinic.

Adult↗
PubMed2002

Long-term prognostic value of dobutamine stress 99mTc-sestamibi SPECT: single-center experience with 8-year follow-up.

PURPOSE: To determine the long-term prognostic value of dobutamine stress technetium 99m (99mTc)-labeled sestamibi single photon emission computed tomography (SPECT) in patients with limited exercise capacity. MATERIALS AND METHODS: Clinical data and SPECT results were analyzed in 531 consecutive patients. Follow-up was successful in 528 (99.4%) patients; 55 underwent early revascularization and were excluded. Normal or abnormal findings were considered in the absence or presence of fixed and/or reversible perfusion defects. A summed stress score was calculated to estimate the extent and severity of perfusion defects. Univariate and multivariate Cox proportional hazards regression models were used to identify independent predictors of late cardiac events. The incremental value of myocardial perfusion scintigraphy over clinical variables in predicting events was determined according to two models. The probability of survival was calculated by using the Kaplan-Meier method. RESULTS: Findings were abnormal in 312 patients. During 8.0 years +/- 1.5 of follow-up (range, 4.5-10.6 years), cardiac death occurred in 67 patients (total deaths, 165); nonfatal myocardial infarction, in 34; and late revascularization, in 49. The annual rates for cardiac death, cardiac death or infarction, and all events were 0.9%, 1.2%, and 1.5%, respectively, after normal findings and 2.7%, 3.4%, and 4.4%, respectively, after abnormal findings (P <.05). In a multivariable Cox proportional hazards model, not only an abnormal finding but also the summed stress score provided incremental prognostic information in addition to clinical data. The hazard ratio for cardiac death was 1.09 (95% CI: 1.01, 1.18) per 1-unit increment of the summed stress score. CONCLUSION: The incremental prognostic value of dobutamine stress 99mTc-sestamibi SPECT over clinical data was maintained over an 8-year follow-up in patients with limited exercise capacity.

Coronary Disease↗
PubMed2002

Prognostic value of dobutamine-atropine stress myocardial perfusion imaging in patients with diabetes.

OBJECTIVE: Exercise tolerance in patients with diabetes is frequently impaired due to noncardiac disease such as claudication and polyneuropathy. This study assesses the prognostic value of dobutamine stress myocardial perfusion imaging in patients with diabetes. RESEARCH DESIGN AND METHODS: A total of 207 consecutive diabetic patients who were unable to undergo exercise stress testing underwent dobutamine-atropine stress myocardial perfusion imaging. Follow-up was successful in 206 of 207 (99.5%) patients. A total of 12 patients underwent early (<60 days) revascularization and were excluded from the analysis. End points during follow-up were hard cardiac events, defined as cardiac death and nonfatal myocardial infarction. RESULTS: Abnormal myocardial perfusion was detected in 125 (64%) patients. During 4.1 +/- 2.4 years of follow-up, 73 (38%) deaths occurred, 36 (49%) of which were due to cardiac causes. Nonfatal myocardial infarction occurred in 7 (4%) patients, and 45 (23%) patients underwent late coronary revascularization. Cardiac death occurred in 2 of 69 (3%) patients with normal myocardial perfusion and in 34 of 125 (27%) patients with perfusion abnormalities (P < 0.0001). A multivariable Cox proportional hazard model demonstrated that, in addition to clinical and stress test data, an abnormal scan had an incremental prognostic value for prediction of cardiac death (hazard ratio 7.2, 95% CI 1.7-30). The summed stress score was an important predictor of cardiac death; the hazard ratio was 1.2 (95% CI 1.07-1.34) per one-unit increment. CONCLUSIONS: Dobutamine-atropine stress myocardial perfusion imaging provides additional prognostic information incremental to clinical data in patients with diabetes who are unable to undergo exercise stress testing.

Aged↗
PubMed2002

Prognostic value of dobutamine-atropine stress (99m)Tc-tetrofosmin myocardial perfusion SPECT in patients with known or suspected coronary artery disease.

UNLABELLED: 99mTc-Tetrofosmin is a recently introduced radioactive isotope for the assessment of myocardial perfusion. Data regarding the prognostic value of stress imaging using this isotope are scarce. The aim of this study was to assess the prognostic value of dobutamine-atropine (99m)Tc-tetrofosmin SPECT for the prediction of late cardiac events in patients with known or suspected coronary artery disease. METHODS: A total of 721 consecutive patients with limited exercise capacity underwent dobutamine-atropine stress (99m)Tc-tetrofosmin SPECT. Follow-up was successful in 719 of 721 patients (99.7%). Twenty-eight patients who underwent early revascularization were excluded. RESULTS: Myocardial perfusion abnormalities were detected in 381 patients (55%) and included fixed defects in 190 patients (27%) and reversible defects 191 patients (28%). During a mean follow-up period of 37 +/- 17 mo, there were 150 deaths (22%), of which 62 (41%) were attributed to cardiac causes. Nonfatal myocardial infarction occurred in 23 patients (3%), and late (>3 mo) coronary revascularization was performed on 21 patients (3%). The cardiac death rate was 1%/y in patients with a normal scan and 5.1%/y in patients with an abnormal scan (P < 0.0001). In a multivariable Cox proportional-hazards model, the presence of abnormal perfusion was independently associated with an increased risk of cardiac death, after adjusting for clinical and stress test data (hazard ratio, 8.2; 95% confidence interval, 3.2-21). CONCLUSION: Dobutamine-atropine stress (99m)Tc-tetrofosmin SPECT is a useful imaging method for distinguishing patients at high and low risk of future cardiac events. The presence of perfusion abnormalities provides incremental prognostic information to clinical, stress electrocardiographic, and hemodynamic data.

Atropine↗
PubMed2002

Sequential (201)Tl imaging and dobutamine echocardiography to enhance accuracy of predicting improved left ventricular ejection fraction after revascularization.

UNLABELLED: 201Tl imaging and dobutamine echocardiography (DE) can both identify viable myocardium. Prediction of functional outcome after revascularization remains suboptimal with either technique because of the relatively low specificity of (201)Tl and low sensitivity of DE. This study was undertaken to develop an optimal testing strategy for prediction of post-revascularization functional outcome. METHODS: Seventy-three patients (mean [+/-SD] left ventricular ejection fraction [LVEF], 32% +/- 8%) underwent DE and resting (201)Tl SPECT (4-h delayed imaging) before surgical revascularization. Dysfunctional segments with (201)Tl activity > or = 50% or with contractile reserve were considered viable. LVEF was assessed before and 3-6 mo after revascularization. RESULTS: Analysis of receiver operator characteristic curves showed that the optimum criteria to predict improvement (> or = 5%) in LVEF after revascularization were > or = 6 viable dysfunctional segments (using a 16-segment model) on (201)Tl and > or = 4 segments on DE. Sensitivity and specificity were 84% and 63% for (201)Tl (P < 0.05 vs. DE) and 63% and 85% for DE (P < 0.05 vs. (201)Tl). Changing the (201)Tl criteria to improve specificity to 78% (> or = 8 segments) yielded a low sensitivity of 44%, and changing the DE criteria to improve sensitivity to 84% (> or = 2 segments) lowered specificity to 56%. Two sequential testing strategies were explored to achieve optimal sensitivity and specificity. In strategy 1, 33 (45%) of 73 patients with an intermediate likelihood of viability by (201)Tl (5-8 viable segments) underwent DE. In strategy 2, 31 (42%) of 73 patients with an intermediate likelihood of viability by DE (2-4 viable segments) underwent (201)Tl. For strategy 1, sensitivity did not change significantly (69%), whereas specificity was improved significantly (93%, P < 0.01 vs. (201)Tl). For strategy 2, sensitivity improved significantly (78%, P < 0.05 vs. DE) and specificity remained unchanged (80%). CONCLUSION: Sequential testing by (201)Tl SPECT and DE in a subgroup of patients with an intermediate likelihood of viability by either test significantly enhanced prediction of post-revascularization improvement of LVEF.

Coronary Disease↗
PubMed2002

Dobutamine stress myocardial perfusion imaging in coronary artery disease.

The accurate noninvasive diagnosis and functional evaluation of coronary artery disease is an important step in selecting the appropriate management strategy. Dobutamine stress myocardial perfusion imaging is an alternative to exercise in patients with limited exercise capacity. In many centers, the test is performed on patients who have a contraindication for vasodilator stress testing. Recent studies have shown hyperemia induced by the standard dobutamine-atropine stress test is not less than hyperemia induced by dipyridamole. The feasibility of the test is 90% and is often higher in patients without beta-blocker therapy. The safety of the test has been well studied and was also demonstrated in specific patients groups, such as patients with left ventricular dysfunction, the elderly, and heart transplant recipients. The diagnostic accuracy has been demonstrated in patients with and without myocardial infarction and in specific groups such as those with hypertension, left ventricular hypertrophy, and heart transplant recipients and after revascularization. The technique has a high sensitivity for prediction of functional recovery in patients with myocardial dysfunction referred for revascularization. The presence and severity of myocardial perfusion abnormalities assessed by this method are powerful predictors of cardiac events, incremental to clinical data. This article describes the methodology, safety, feasibility, diagnostic accuracy, and prognostic value of dobutamine stress myocardial perfusion imaging in patients with known or suspected coronary artery disease, with additional considerations for the application of the test in specific patient groups.

Angioplasty, Balloon, Coronary↗
PubMedDate not supplied

Incidence and predictors of heart failure during long-term follow-up after stress Tc-99m sestamibi tomography in patients with suspected coronary artery disease.

BACKGROUND: Heart failure is a major cause of morbidity and death in patients with coronary artery disease (CAD). The aim of this study was to define the incidence and predictors of heart failure during long-term follow-up in patients with suspected CAD referred for stress myocardial perfusion imaging. METHODS AND RESULTS: We studied 787 patients (mean age, 57 +/- 12 years; 470 men) with suspected CAD who had no history of previous myocardial infarction or heart failure with exercise (n = 508) or dobutamine (n = 279) stress technetium 99m sestamibi single photon emission computed tomography. Patients were followed up for the occurrence of heart failure, nonfatal myocardial infarction, and death. An abnormal perfusion scan (reversible or fixed perfusion defect) was detected in 341 patients (43%). During a mean follow-up of 6.7 +/- 2.3 years, heart failure occurred in 46 patients (6%), 170 patients (22%) died, and 52 patients (7%) had nonfatal myocardial infarction. Patients in whom heart failure developed were older (mean age, 60 +/- 12 years vs 56 +/- 12 years; P = .01) and were more likely to be men (34 [74%] vs 436 [59%], P = .01) and to have an abnormal scan (32 [70%] vs 309 [42%], P = .0002) compared with patients without heart failure. Nonfatal myocardial infarction occurred before the onset of heart failure in only 3 patients (7%). By multivariate analysis, predictors of heart failure were age (risk ratio [RR], 1.04 [95% CI, 1.01-1.08]), male gender (RR, 2 [95% CI, 1.3-4.5]), resting heart rate (RR, 1.1 [95% CI, 1.05-1.2]), and abnormal scan (RR, 2.3 [95% CI, 1.4-3.9]). The annual mortality rate was 15% after the diagnosis of heart failure. CONCLUSION: In patients with suspected CAD and no history of myocardial infarction, late heart failure is predicted by age, gender, resting heart rate, and abnormal perfusion, and it is associated with a substantial mortality rate. The majority of heart failure events are heralded by perfusion abnormalities on sestamibi single photon emission computed tomography but not by an earlier myocardial infarction.

Age Distribution↗
PubMedDate not supplied

Prognostic value of stress Tc-99m tetrofosmin SPECT in patients with previous myocardial infarction: impact of scintigraphic extent of coronary artery disease.

BACKGROUND: Our objective was to assess the prognostic value of the scintigraphic extent of coronary artery disease on stress technetium 99m tetrofosmin single photon emission computed tomography in patients with previous myocardial infarction. METHODS AND RESULTS: We studied 383 patients (280 men and 103 women; mean age, 60 +/- 11 years) more than 3 months after an acute myocardial infarction by exercise bicycle or dobutamine (up to 40 mug . kg -1 . min -1 ) stress Tc-99m tetrofosmin myocardial perfusion tomography. Stress images were acquired 1 hour after stress, and rest images were acquired 24 hours after stress testing. An abnormal study was defined as one demonstrating a reversible or fixed perfusion abnormality. Myocardial segments were assigned to corresponding coronary arteries as follows: the apex, anterior wall, and anterior septum were assigned to the left anterior descending coronary artery; the posterolateral wall was assigned to the left circumflex artery; and the basal posterior septum and inferior wall were assigned to the right coronary artery. During a mean follow-up of 4.3 +/- 2.1 years, 48 cardiac events occurred (36 cardiac deaths and 12 nonfatal myocardial infarctions). Myocardial perfusion was normal in 51 patients, abnormal in a single-vessel distribution in 170 patients, and abnormal in a multivessel distribution in 162 patients. The annual cardiac event rates in these groups were 0.4%, 2.6%, and 4%, respectively. In a multivariate analysis model, independent predictors of cardiac events were diabetes mellitus (odds ratio [OR], 2.3; 95% confidence interval [CI], 1.4-4.5), history of congestive heart failure (OR, 2.7; 95% CI, 1.4-4), age (OR, 1.05; 95% CI, 1.01-1.08), and scintigraphic extent of coronary artery disease (OR, 4.2; 95% CI, 1.8-9.1). CONCLUSION: Stress Tc-99m tetrofosmin myocardial perfusion imaging provides independent prognostic information for the risk stratification of patients with previous myocardial infarction. The event rate is directly related to the scintigraphic extent of coronary artery disease. Patients with normal perfusion have an excellent event-free survival rate.

Coronary Artery Disease↗