Coronary Artery Disease: Williams KA

Mehta R, Ward RP, Chandra S, Agarwal R, Williams KA, Anonymous00369, Anonymous00370. · Section of Cardiology, University of Chicago, Chicago, Ill 60637, USA. · J Nucl Cardiol. · Pubmed #18513640 No free full text.

Abstract: BACKGROUND: The American College of Cardiology Foundation/American Society of Nuclear Cardiology appropriateness criteria (AC) were created to guide responsible use of single photon emission computed tomography (SPECT). Clinical applicability of the AC has not been evaluated. METHODS AND RESULTS: Indications for testing were determined in 1209 patients and categorized as having appropriate, uncertain, or inappropriate indications; the specialty of the ordering physician was noted. There were 940 (80%) appropriate, 154 (13%) inappropriate, and 79 (7%) uncertain tests; 36 tests were labeled "no category," as these were ordered for indications not clearly addressed in the AC. Inappropriate studies had more normal and lower summed stress scores, although there remained a high proportion of abnormal SPECT studies in this group (26% of women and 50% of men). Women had lower summed stress scores and more normal tests in the appropriate and inappropriate groups. Studies ordered by anesthesiologists for preoperative evaluation were more likely to be deemed inappropriate than other specialty groups. CONCLUSION: In evaluating the AC in a single-center academic setting, the majority of studies are appropriate, but a large proportion of ordered SPECT studies were categorized as uncertain, inappropriate, or no category. Although the inappropriate studies showed less ischemia than other groups, especially in women, a substantial portion of these studies (32%) were abnormal.

Klocke FJ, Baird MG, Lorell BH, Bateman TM, Messer JV, Berman DS, O'Gara PT, Carabello BA, Russell RO, Cerqueira MD, St John Sutton MG, DeMaria AN, Udelson JE, Kennedy JW, Verani MS, Williams KA, Antman EM, Smith SC, Alpert JS, Gregoratos G, Anderson JL, Hiratzka LF, Faxon DP, Hunt SA, Fuster V, Jacobs AK, Gibbons RJ, Russell RO, Anonymous00288, Anonymous00289, Anonymous00290. · No affiliation provided · J Am Coll Cardiol. · Pubmed #14522503 No free full text.

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Klocke FJ, Baird MG, Lorell BH, Bateman TM, Messer JV, Berman DS, O'Gara PT, Carabello BA, Russell RO, Cerqueira MD, St John Sutton MG, DeMaria AN, Udelson JE, Kennedy JW, Verani MS, Williams KA, Antman EM, Smith SC, Alpert JS, Gregoratos G, Anderson JL, Hiratzka LF, Faxon DP, Hunt SA, Fuster V, Jacobs AK, Gibbons RJ, Russell RO, Anonymous00249, Anonymous00250, Anonymous00251. · No affiliation provided · Circulation. · Pubmed #12975245 links to  free full text

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Roberts R, Stewart AF, Wells GA, Williams KA, Kavaslar N, McPherson R. · University of Ottawa Heart Institute, Ontario. · Can J Cardiol. · Pubmed #17668082 No free full text.

Abstract: BACKGROUND: Coronary artery disease (CAD) remains the number one killer in the western world. Genetics accounts for greater than 50% of the risk for CAD. Genetic screening and early prevention in individuals identified as being at increased risk could dramatically reduce the prevalence of CAD, thus necessitating the identification of genes predisposing to CAD. Studies of genes identified by the candidate gene approach have not been replicated due, in part, to inadequate sample size. Genome-wide scan association studies have been limited by the use of thousands of markers rather than the hundreds of thousands required, and by the use of hundreds of individuals rather than the thousands required. Replication of positive findings in an independent population is essential. To detect a minor allele frequency of 5% or greater with an odds ratio for risk of 1.3 or greater and 90% power, an estimated 14,000 (9000 affected and 5000 control) subjects are required. METHODS: The Affymetrix GeneChip Human Mapping 500K Array Set (Affymetrix Inc, USA) provides a marker every 6000 base pairs as required, and is being used to genotype 1000 cases of premature CAD and 1000 normal subjects, followed by replication in 8000 affected individuals and 4000 control subjects. The phenotype is confirmed or excluded by coronary arteriograms by catheterization or multislice computed tomography. RESULTS: Since 2005, more than 800 million genotypes have been performed and analyses performed on 500 control subjects and 500 affected individuals. Several thousand significant single nucleotide polymorphisms and 130 clusters associated with CAD have been identified. CONCLUSIONS: This is the first genome-wide scan using the 500,000 marker set in a case-control association study for CAD genes. Several genes associated with CAD appear promising.

Okwuosa T, Williams KA. · Department of Internal Medicine, University of Chicago, Chicago, Ill, USA. · J Nucl Cardiol. · Pubmed #16580948 No free full text.

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Williams KA, Schuster RA, Williams KA, Schneider CM, Pokharna HK. · Department of Medicine, University of Chicago, 5758 S. Maryland Avenue, MC9025, Chicago, IL 60637, USA. · J Nucl Cardiol. · Pubmed #12900739 No free full text.

Abstract: BACKGROUND: This study sought to improve the detection of multivessel coronary artery disease (CAD) with the use of rest and exercise single photon emission computed tomography (SPECT) perfusion scintigraphy by developing a processing scheme, which provides proper regional normalization of the images for interpretation. When SPECT perfusion images are interpreted, one area of myocardium serves as "normal." We hypothesized that if this "normal" region changes location from rest to stress, the stress images must be adjusted for proper interpretation. By taking into account the level of tracer activity in this "normal" area on the resting images, we could more accurately identify patients with multivessel CAD.Methods and results Dual-isotope rest (thallium 201) and exercise dobutamine or adenosine stress (technetium 99m sestamibi) perfusion SPECT studies were examined in 258 patients with 2- or 3-vessel CAD on coronary arteriography performed within 6 months of each other (mean interval, 19 days). If a shift in regional location of the "normal" segment from rest to stress was present, the images were (1) interpreted in the usual fashion for the number of vessels with ischemia (PRE-NORM) and (2) reinterpreted after quantitative normalization (ie, adjusting the display window until the intensity of the "normal" segment was matched at rest and stress [POST-NORM]). Interpretation was performed with blinding to arteriographic results. An angiographic stenosis was defined as luminal diameter stenosis greater than 50%. Three control groups comprising (1) single-vessel CAD (n = 119), (2) no significant angiographic CAD (n = 118), and (3) a normalcy group of low pre- and post-test probability of CAD (n = 44) were also studied to determine the incidence of false-positive results induced by the renormalization technique. A shift in the "normal" segment occurred in 81 studies of 258 patients (31%), 80 of which were read as abnormal PRE-NORM (sensitivity, 99%); however, for their 216 stenosed vessels, only 143 were detected PRE-NORM (vessel sensitivity, 66%; accuracy, 65%). The mean POST-NORM change in the display was 11%. POST-NORM, all 82 patients' studies were interpreted as abnormal (sensitivity, 100%), and 196 of 216 vascular territories were abnormal (vessel sensitivity, 91%; accuracy, 83%; both P <.0001 vs PRE-NORM). In the single-vessel disease, no significant disease, and normalcy groups, 19 of 119, 15 of 118, and 11 of 44 patients, respectively, demonstrated a shift in the peak pixel location. However, there were no significant changes in single-vessel sensitivity, angiographic specificity, or normalcy in these patients. CONCLUSIONS: With multivessel CAD, the "normal" region on SPECT often changes in location from rest to stress, potentially masking the extent and severity of multivessel ischemia. Renormalization of the images to match their resting level before image interpretation allows diagnosis of contralateral ischemia and strikingly improves the detection of multivessel CAD, without a substantive loss in specificity.

Williams KA, Schuster RA, Williams KA, Schneider CM, Pokharna HK. · Department of Medicine, University of Chicago, 5758 S. Maryland Avenue, MC9025, Chicago, IL 60637, USA. · J Nucl Cardiol. · Pubmed #12900739 No free full text.

Abstract: BACKGROUND: This study sought to improve the detection of multivessel coronary artery disease (CAD) with the use of rest and exercise single photon emission computed tomography (SPECT) perfusion scintigraphy by developing a processing scheme, which provides proper regional normalization of the images for interpretation. When SPECT perfusion images are interpreted, one area of myocardium serves as "normal." We hypothesized that if this "normal" region changes location from rest to stress, the stress images must be adjusted for proper interpretation. By taking into account the level of tracer activity in this "normal" area on the resting images, we could more accurately identify patients with multivessel CAD.Methods and results Dual-isotope rest (thallium 201) and exercise dobutamine or adenosine stress (technetium 99m sestamibi) perfusion SPECT studies were examined in 258 patients with 2- or 3-vessel CAD on coronary arteriography performed within 6 months of each other (mean interval, 19 days). If a shift in regional location of the "normal" segment from rest to stress was present, the images were (1) interpreted in the usual fashion for the number of vessels with ischemia (PRE-NORM) and (2) reinterpreted after quantitative normalization (ie, adjusting the display window until the intensity of the "normal" segment was matched at rest and stress [POST-NORM]). Interpretation was performed with blinding to arteriographic results. An angiographic stenosis was defined as luminal diameter stenosis greater than 50%. Three control groups comprising (1) single-vessel CAD (n = 119), (2) no significant angiographic CAD (n = 118), and (3) a normalcy group of low pre- and post-test probability of CAD (n = 44) were also studied to determine the incidence of false-positive results induced by the renormalization technique. A shift in the "normal" segment occurred in 81 studies of 258 patients (31%), 80 of which were read as abnormal PRE-NORM (sensitivity, 99%); however, for their 216 stenosed vessels, only 143 were detected PRE-NORM (vessel sensitivity, 66%; accuracy, 65%). The mean POST-NORM change in the display was 11%. POST-NORM, all 82 patients' studies were interpreted as abnormal (sensitivity, 100%), and 196 of 216 vascular territories were abnormal (vessel sensitivity, 91%; accuracy, 83%; both P <.0001 vs PRE-NORM). In the single-vessel disease, no significant disease, and normalcy groups, 19 of 119, 15 of 118, and 11 of 44 patients, respectively, demonstrated a shift in the peak pixel location. However, there were no significant changes in single-vessel sensitivity, angiographic specificity, or normalcy in these patients. CONCLUSIONS: With multivessel CAD, the "normal" region on SPECT often changes in location from rest to stress, potentially masking the extent and severity of multivessel ischemia. Renormalization of the images to match their resting level before image interpretation allows diagnosis of contralateral ischemia and strikingly improves the detection of multivessel CAD, without a substantive loss in specificity.

Tolleson TR, O'Shea JC, Bittl JA, Hillegass WB, Williams KA, Levine G, Harrington RA, Tcheng JE. · Duke University Medical Center and Clinical Research Institute, Durham, NC 27705, USA. · J Am Coll Cardiol. · Pubmed #12575964 No free full text.

Abstract: OBJECTIVES: We evaluated the relationship between the degree of heparin anticoagulation and clinical efficacy and bleeding in patients undergoing contemporary percutaneous coronary intervention (PCI) with stent implantation. BACKGROUND: Despite universal acceptance of heparin anticoagulation as a standard of care in PCI, considerable controversy still exists regarding the appropriate dosing of heparin. METHODS: The study population (n = 2,064) comprised all patients enrolled in the Enhanced Suppression of the Platelet IIb/IIIa Receptor with Integrilin Therapy (ESPRIT) trial. The index activated clotting time (ACT) was defined as the ACT measured after the last heparin dose and before first device activation and was correlated with outcome and bleeding events. RESULTS: No association was observed between decreasing ACT levels and the rate of ischemic events in the treatment or placebo arms. The incidence of the primary composite end point (death, myocardial infarction, urgent target vessel revascularization, and thrombotic bailout glycoprotein IIb/IIIa inhibitor therapy at 48 h) was actually lowest in the lowest ACT tertile for both the placebo (10.0%) and treatment groups (6.1%). When analyzed by tertile, major bleeding rates did not increase in the lowest ACT tertile in patients given placebo (0.6%) versus those receiving eptifibatide (0.7%). Major bleeding rates increased as the ACT increased in the eptifibatide-treated patients. CONCLUSIONS: Ischemic end points in patients undergoing contemporary PCI with stent placement do not increase by decreasing ACT levels, at least to a level of 200 s. Bleeding events do increase with increasing ACT levels and are enhanced with eptifibatide treatment. An ACT of 200 to 250 s is reasonable in terms of efficacy and safety with the use of contemporary technology and pharmacotherapy.

Reddan DN, O'Shea JC, Sarembock IJ, Williams KA, Pieper KS, Santoian E, Owen WF, Kitt MM, Tcheng JE. · Division of Nephrology and Duke Institute for Renal Outcomes and Health Policy, Durham, North Carolina 27705, USA. · Am J Cardiol. · Pubmed #12505565 No free full text.

Abstract: The role of platelet glycoprotein IIb/IIIa inhibitor therapy in patients with mild renal impairment is not well characterized. Our objective was to explore the associations of creatinine clearance (CrCl) with outcomes in a trial of eptifibatide therapy in patients who underwent percutaneous coronary intervention (PCI). We analyzed 48-hour and 30-day outcomes of patients enrolled in the Enhanced Suppression of the Platelet IIb/IIIa Receptor with Integrilin Therapy (ESPRIT) trial. Patients were randomly assigned to placebo or eptifibatide as an adjunct to stent implantation (1,755 with CrCl > or =60 ml/min and 289 with CrCl <60 ml/min). CrCl was calculated using the Cockcroft and Gault formula, and the associations of CrCl with outcomes were evaluated using logistic regression models. Patients with CrCl <60 ml/min were more likely to be older, women, hypertensive, and have a history of coronary artery bypass surgery, stroke, or peripheral vascular disease. The interaction of eptifibatide with CrCl had borderline significance for the 30-day outcome (p = 0.109). Treatment effect trended toward a greater magnitude in patients with lower CrCl (60 ml/min) (odds ratio 0.53, confidence interval 0.34 to 0.83) compared with those with higher CrCl (90 ml/min) (odds ratio 0.68, confidence interval 0.49 to 0.94). An accompanying increase in bleeding risk also was not apparent with lower CrCl. The treatment effect of eptifibatide is realized regardless of renal function and trends toward being greater in patients with mild renal impairment.

Shin JH, Pokharna HK, Williams KA, Mehta R, Ward RP. · Section of Cardiology, Department of Medicine, University of Chicago, University of Chicago Hospitals, Chicago, IL 60637, USA. · J Nucl Cardiol. · Pubmed #19466502 No free full text.

Abstract: BACKGROUND: Recent evidence suggests that combining supine and prone acquisitions during stress-gated SPECT myocardial perfusion imaging (MPS) improves detection of obstructive coronary artery disease (CAD), though the additional imaging time required may not be feasible in routine clinical practice. MPS with prone-only acquisitions is occasionally performed in many laboratories, though little is known about the ability of modern MPS with prone-only acquisitions to detect obstructive CAD. Our goal was to assess the ability of MPS with prone-only acquisitions to detect obstructive CAD as determined by coronary angiography. METHODS AND RESULTS: We studied 386 patients referred for MPS with either recent coronary angiography or a low pretest likelihood of coronary artery disease. All rest and stress images were obtained exclusively in the prone position. The sensitivity of prone-only MPS was 88% for detecting > or =50% coronary artery stenosis and 92% for detecting > or =70% coronary artery stenosis as determined by coronary angiography. Normalcy rate for prone-only MPS in patients with low probability for CAD was 95%, and normalcy rates did not significantly differ among coronary artery distributions. CONCLUSIONS: The findings of this study suggest that MPS using prone-only acquisitions is a reasonable diagnostic option for the detection of ischemia due to obstructive coronary artery disease.

Hendel RC, Berman DS, Di Carli MF, Heidenreich PA, Henkin RE, Pellikka PA, Pohost GM, Williams KA, Wolk MJ, Alagona P, Bateman TM, Cerqueira MD, Corbett JR, Dean AJ, Dehmer GJ, Goldbach P, Gordon L, Kushner FG, Kwong RY, Min J, Quinones MA, Ward RP, Yang SH, Allen J, Brindis RG, Douglas PS, Patel M, Peterson E. · Appropriate Use Criteria for Radionuclide Imaging Writing Group-Midwest Heart Specialists, Winfield, IL, USA. · Circulation. · Pubmed #19451357 No free full text.

Abstract: The American College of Cardiology Foundation (ACCF), along with key specialty and subspecialty societies, conducted an appropriate use review of common clinical scenarios where cardiac radionuclide imaging (RNI) is frequently considered. This document is a revision of the original Single-Photon Emission Computed Tomography Myocardial Perfusion Imaging (SPECT MPI) Appropriateness Criteria, published 4 years earlier, written to reflect changes in test utilization and new clinical data, and to clarify RNI use where omissions or lack of clarity existed in the original criteria. This is in keeping with the commitment to revise and refine appropriate use criteria (AUC) on a frequent basis. The indications for this review were drawn from common applications or anticipated uses, as well as from current clinical practice guidelines. Sixty-seven clinical scenarios were developed by a writing group and scored by a separate technical panel on a scale of 1 to 9 to designate appropriate use, inappropriate use, or uncertain use. In general, use of cardiac RNI for diagnosis and risk assessment in intermediate- and high-risk patients with coronary artery disease (CAD) was viewed favorably, while testing in low-risk patients, routine repeat testing, and general screening in certain clinical scenarios were viewed less favorably. Additionally, use for perioperative testing was found to be inappropriate except for high selected groups of patients. It is anticipated that these results will have a significant impact on physician decision making, test performance, and reimbursement policy, and will help guide future research.

Ward RP, Weiner J, Taillon LA, Ghani SN, Min JK, Williams KA. · Section of Cardiology, Department of Medicine, University of Chicago Hospitals, Chicago, Illinois, USA. · Am J Cardiol. · Pubmed #18312766 No free full text.

Abstract: Erectile dysfunction (ED) has been associated with a future risk of myocardial infarction, yet the findings on stress testing in men with ED and without previous coronary artery disease are unknown. Stress myocardial perfusion single-photon emission computed tomographic imaging (MPI) allows detection of coronary artery disease and predicts cardiovascular prognosis. Our goal was to determine the association between ED and findings at stress MPI testing in men without previous coronary artery disease. Five hundred seventy-five men without previous coronary artery disease referred for stress MPI were prospectively screened for ED with the validated International Index of Erectile Function. ED was present in 46% of subjects, and ED was associated with more mild (summed stress score >or=4) and severe (summed stress score >8) coronary artery disease and with more composite high-risk stress MPI findings (summed stress score >8, left ventricular ejection fraction <40%, transient ischemic dilation). In patients referred for exercise, ED was associated with a lower Duke treadmill score. On multivariate analysis, ED was found to be an independent predictor of a summed stress score >or=4, a summed stress score >8, and composite high-risk MPI findings. In conclusion, in men without known coronary artery disease referred for stress MPI testing, ED is associated with adverse prognostic indicators at MPI testing including coronary artery disease and high-risk MPI findings.

Smelley MP, Virnich DE, Williams KA, Ward RP. · Section of Cardiology, Department of Medicine, University of Chicago, Chicago, Ill, USA. · J Nucl Cardiol. · Pubmed #17679062 No free full text.

Abstract: BACKGROUND: A hypertensive response to exercise (HRE) is associated with false-positive stress echocardiograms and myocardial perfusion single photon emission computed tomography (myocardial perfusion imaging [MPI]) defects even in the absence of coronary artery disease (CAD). Transient ischemic dilation (TID) of the left ventricle on stress MPI is a marker of severe CAD and future cardiac events. This study evaluated the association between an HRE and TID. METHODS AND RESULTS: Blinded quantitative TID assessment was performed in 125 patients who had an HRE and a summed stress score (SSS) of less than 4, as well as 125 control patients with an SSS of less than 4 and without an HRE matched for age, gender, and resting systolic blood pressure. Cardiac comorbidities, pretest Framingham risk, and exercise results were recorded. TID was defined as a stress-to-rest volume ratio of 1.22 or greater. An HRE was associated with a high prevalence of TID and significantly more TID than no HRE (25.6% vs 11.2%; odds ratio, 3.00 [95% confidence interval, 1.41-6.38]). TID was more prevalent even in subgroups with a low pretest probability CAD, including those without diabetes mellitus or angina. On conditional logistic regression analysis, an HRE was found to be independently associated with TID after consideration of other clinical and exercise MPI variables (odds ratio, 2.72 [95% confidence interval, 1.01-7.31]). CONCLUSION: An HRE is associated with a high prevalence of TID in patients without other significant perfusion defects, possibly as a result of global subendocardial ischemia induced by the HRE.

Min JK, Williams KA, Okwuosa TM, Bell GW, Panutich MS, Ward RP. · Section of Cardiology, Department of Medicine, The University of Chicago Hospitals, Chicago, Ill 60637, USA. · Arch Intern Med. · Pubmed #16432089 links to  free full text

Abstract: BACKGROUND: Recent evidence suggests a strong link between erectile dysfunction (ED) and atherosclerotic vascular disease. Stress myocardial perfusion single-photon emission computed tomography (MPS) is a widely used noninvasive imaging modality that allows diagnosis of coronary heart disease and stratification of cardiovascular risk. We sought to determine the relationship between ED and coronary heart disease in men referred for MPS. METHODS: A total of 221 men referred for MPS were prospectively screened for ED with a validated questionnaire. Patient characteristics, MPS findings, and exercise results were correlated with ED. RESULTS: Erectile dysfunction was present in 54.8% of the patients. Patients with ED exhibited more severe coronary heart disease (MPS summed stress score >8) (43.0% vs 17.0%; P<.001) and left ventricular dysfunction (left ventricular ejection fraction <50%) (24.0% vs 11.0%; P=.01) than those without ED. Erectile dysfunction was associated with a shorter exercise time (8.0 vs 10.1 minutes; P<.001) and lower Duke treadmill score (4.4 vs 8.4; P<.001). Multivariate analysis showed ED to be an independent predictor of severe coronary heart disease (odds ratio, 2.50; 95% confidence interval, 1.24-5.04; P = .01) and high-risk MPS findings (summed stress score >8, transient ischemic dilation, or left ventricular ejection fraction <35%) (odds ratio, 2.86; 95% confidence interval, 1.43-5.74; P = .003). CONCLUSIONS: Erectile dysfunction is common in men referred for MPS, is associated with markers of adverse cardiovascular prognosis, and is an independent predictor of severe coronary heart disease and high-risk MPS findings. These results suggest that questioning about sexual function may be a useful tool for stratifying risk in individuals with suspected coronary heart disease.

Ling MC, Ruddy TD, deKemp RA, Ukkonen H, Duchesne L, Higginson L, Williams KA, McPherson R, Beanlands R. · Division of Cardiology, Department of Medicine, Cardiac PET Centre, University of Ottawa Heart Institute, Ottawa, Ontario, Canada. · Am Heart J. · Pubmed #15976803 No free full text.

Abstract: BACKGROUND: Recent data suggest an early outcome benefit with reduction in cholesterol using statin therapy in patients with coronary artery disease (CAD). This may be caused by effects of low-density lipoprotein cholesterol (LDL-C) reduction on endothelial function and vascular reactivity in the coronary bed. The aim of this randomized placebo-controlled study was to examine the early effects of important reductions in LDL-C on myocardial perfusion and peripheral endothelial function. METHODS AND RESULTS: Seventy-two patients with CAD and LDL-C between 3.0 and 5.9 mmol/L (116-228 mg/dL) were randomized to receive simvastatin 20 mg daily, pravastatin 40 mg daily, or placebo for 8 weeks. At baseline, 2 weeks, and 8 weeks, patients underwent dynamic positron emission tomography perfusion imaging to quantify the retention of rubidium-82 as a measure of myocardial flow at rest and after dipyridamole stress. Patients also underwent brachial artery ultrasound to measure endothelium-dependent flow-mediated vasodilatation. At 2 and 8 weeks, the simvastatin and pravastatin groups showed a significant reduction (P < .001) in LDL-C compared with placebo. At 8 weeks, simvastatin led to an improvement in flow-mediated vasodilatation compared with placebo (6.86% +/- 4.4% vs 3.44% +/- 4.0%, P < .05), whereas pravastatin was not significantly different than placebo (5.62% +/- 4.1% vs 3.44% +/- 4.0%, P = NS). Despite this improvement in peripheral endothelial function with simvastatin, there were no significant differences observed in global stress flow and coronary flow reserve at 8 weeks with either drug. CONCLUSIONS: Short-term LDL reduction with simvastatin therapy improves peripheral endothelial function in patients with stable CAD, although an early effect on coronary vascular reactivity could not be demonstrated.

Ward RP, Pokharna HK, Lang RM, Williams KA. · Department of Medicine, University of Chicago, Chicago, IL 60637, USA. · J Nucl Cardiol. · Pubmed #14569244 No free full text.

Abstract: BACKGROUND: Patients with apical hypertrophic cardiomyopathy (ACM) are often referred for myocardial perfusion single photon emission computed tomography (SPECT) as a result of marked T-wave inversion and chest pain syndromes. Stress perfusion defects have been reported in ACM, but the characteristic SPECT pattern as well as the typical findings on volume-weighted polar maps has not been described. METHODS AND RESULTS: Dual-isotope rest (thallium 201) and exercise or adenosine stress (technetium 99m tetrofosmin) myocardial perfusion SPECT was performed in 11 patients with ACM, including 8 with either normal coronary arteriography (n = 5) or a low pretest probability of coronary artery disease (CAD) (n = 3), and 14 control patients with concentric left ventricular hypertrophy. An 8-pixel-diameter circular region of interest was used to quantitatively compare apical and septal counts on CEqual volume-weighted polar maps. A characteristic "Solar Polar" map pattern resulting from the increased apical counts was present in each ACM patient at rest, with a mean apical-septal ratio of 1.39 +/- 0.17 (range, 1.23-1.62, P <.01 vs concentric left ventricular hypertrophy group). With stress, there was a significant decrease in the apical-septal ratio (0.96 +/- 0.18, P <.001 vs rest) in the ACM subgroup without CAD. CONCLUSION: Patients with ACM demonstrate a newly described "Solar Polar" map pattern at rest, as well as relative apical ischemia on the stress images even in the absence of CAD.

Williams KA, Hill KA, Sheridan CM. · Department of Medicine, University of Chicago, 5758 S. Maryland Avenue, MC9025, Chicago, IL 60637, USA. · J Nucl Cardiol. · Pubmed #12900744 No free full text.

Abstract: BACKGROUND: This study examined the frequency of reporting noncardiac findings (NCFs), such as malignancies from inspection of raw projection images with dual-isotope single photon emission computed tomography (SPECT) perfusion imaging, which could potentially be of greater clinical importance than myocardial perfusion imaging alone. Dual-isotope (ie, rest thallium 201 and stress technetium 99m sestamibi [MIBI] or Tc-99m tetrofosmin [TET]) SPECT myocardial perfusion imaging combines multipotential tracers for noncardiac purposes (Tl-201 for renal or splenic imaging, inflammation, or lymphoma and MIBI or TET for hepatobiliary imaging and detecting increased mitochondrial number or activity in neoplastic processes). These images are optimally interpreted with cinematic inspection of the raw projection data, but this may not be practiced uniformly in every laboratory. METHODS AND RESULTS: We reviewed 12,526 computer-generated text reports of dual-isotope perfusion SPECT studies from a 6-year period for NCFs. NCFs were categorized by organ and by probability of malignancy: high (eg, focal breast or lung uptake of MIBI or TET), intermediate (eg, lymph node uptake or thyroid abnormalities), or low (eg, filling defects in liver, kidney, spleen, or gall bladder; ascites; or pleural effusions). Confirmatory imaging studies or clinical confirmation for each NCF was sought. There were a total of 207 NCFs identified in 180 reports (1.7% of reports, ranging from 0% to 2.8% of reports of individual interpreters). Of these, 107 NCFs were unsuspected before SPECT; 24% were considered at high probability for malignancy, and 24% were considered intermediate in likelihood of malignancy. Follow-up data were available for 178 NCFs, confirming 88% of these findings, including 82% of breast foci, 62% of lung foci, 86% of hepatobiliary/spleen abnormalities, and 94% of renal abnormalities. The probability of malignancy was highest (82%) in breast or lung foci in which uptake of both Tl-201 and the Tc-99m-labeled agent was present. CONCLUSIONS: In patients referred for evaluation of myocardial perfusion, NCFs are unusual and require systematic and careful inspection of projection images for their detection. With Tl-201, TET, MIBI, or dual-isotope imaging, detecting and reporting NCFs may occasionally result in life-saving early cancer identification.

Williams KA, Schneider CM. · Department of Medicine, The University of Chicago, Illinois 60637, USA. · J Am Coll Cardiol. · Pubmed #10440154 No free full text.

Abstract: OBJECTIVES: This study sought to determine the anatomic and physiologic correlates of increased right ventricular (RV) activity on exercise single-photon emission computed tomography (SPECT) perfusion imaging in patients with coronary artery disease (CAD). BACKGROUND: Because SPECT perfusion imaging delineates relative myocardial blood flow, patients with global left ventricular (LV) hypoperfusion but normal RV perfusion may have increased relative RV tracer uptake as an indicator of multivessel CAD. METHODS: Rest thallium-201 and exercise 99mTc-sestamibi or 99mTc-tetrofosmin SPECT perfusion images were analyzed for peak RV and LV activity (RV:LV index) in 315 patients, including 240 patients with documented CAD, 39 patients with no significant CAD on arteriography, and a "normalcy" group of 36 patients with a low pre- and posttest probability of CAD. RESULTS: Resting RV:LV perfusion index ranged from 0.32 to 0.34 in each group, increasing to 0.36 with exercise in control and normalcy groups. CAD patients with the highest exercise RV:LV were those with severe left main CAD (or "left main equivalent"), with a lesser degree of proximal right CAD (0.51, n = 14, p < 0.001 vs. other groups). An exercise RV:LV >0.42 with a exercise:rest ratio >1.2 was present in 93% patients with this pattern of CAD, but was absent in 97% of the normalcy group, 92% of patients without significant angiographic CAD, and 100% of patients with proximal right CAD tighter than stenoses in the left system. CONCLUSIONS: Increased RV:LV activity exercise may occur in patients with acute RV strain, but is otherwise an indicator of exercise-induced RV:LV perfusion imbalance associated with severe CAD, particularly high-grade left main with less severe proximal right CAD.