Same-day or next-day sentinel node biopsy after lymphoscintigraphy for melanoma using 99m Tc-labelled antimony sulphide colloid.

BACKGROUND: Two recent publications have reported that a shorter interval between preoperative lymphoscintigraphy and sentinel node biopsy (SNB) is associated with improved survival of patients with primary cutaneous melanoma. The aims of this study were to analyse prospectively collected survival data for patients who had SNB on the same day as lymphoscintigraphy or the day after; and to assess tracer migration from sentinel nodes to second-tier nodes after lymphoscintigraphy on the previous day. METHODS: Outcome data were obtained for patients who had lymphoscintigraphy and SNB on the same day (time interval less than 8 h) or the next day (interval more than 16 h). In a separate prospective cohort, same-day and next-day lymphoscintigraphic images of sentinel nodes and second-tier nodes were compared. RESULTS: Following lymphoscintigraphy, 2848 patients had same-day and 3328 had next-day SNB. Survival outcomes did not differ between these groups. In a prospectively studied cohort of 30 patients, none had significant tracer migration from sentinel nodes to second-tier nodes on imaging the following day. CONCLUSION: No difference in survival after same- or next-day sentinel node biopsy is seen when 99m Tc-labelled antimony sulphide colloid is used. This may be because of less tracer migration to second-tier nodes.

ANTECEDENTES: Dos publicaciones recientes han señalado que reducir el intervalo entre la linfografía isotópica preoperatoria y la biopsia del ganglio centinela (sentinel node biopsy, SNB) se asocia con una mejor supervivencia en pacientes con melanoma maligno primario. Los objetivos de este estudio fueron los siguientes: (1) analizar los datos de supervivencia recogidos prospectivamente en pacientes en los que se realiza la SNB el mismo día o al día siguiente de la linfografía isotópica, y (2) evaluar la migración del marcador desde los ganglios centinela a los ganglios de segundo nivel a partir de la linfografía del día anterior. MÉTODOS: Se analizaron los resultados de los pacientes a los que se realizó una linfografía isotópica y la SNB el mismo día (intervalo de tiempo < 8 h) o al día siguiente (intervalo > 16 h). En una cohorte prospectiva diferente, se compararon las imágenes de los ganglios centinela y de los ganglios de segundo nivel en linfografías isotópicas realizadas el mismo día o al día siguiente. RESULTADOS: Tras la linfografía isotópica, se realizó la SNB el mismo día en 2.848 pacientes y al día siguiente en 3.328 pacientes. No hubo diferencias en la supervivencia entre ambos grupos. En una cohorte de 30 pacientes estudiada de forma prospectiva, no hubo migración significativa del trazador de los ganglios centinela a los ganglios de segundo nivel en las imágenes obtenidas al día siguiente. CONCLUSIÓN: La mejor supervivencia que se obtiene cuando se realiza la SNB poco después de la linfografía isotópica podría explicarse por una diferencia en la migración del trazador a los ganglios de segundo nivel entre los dos marcadores utilizados: nanocoloide de albúmina humana o coloide de sulfuro de antimonio, ambos marcados con 99mTc. En este estudio y con este último marcador, no se observó migración a ganglios de segundo nivel durante la noche.

High-resolution lymphoscintigraphy is essential for recognition of the significance of internal mammary nodes in breast cancer.

BACKGROUND: Sentinel node biopsy (SNB) of internal mammary nodes (IMNs) in breast cancer is controversial. Most centers rarely identify IMN on lymphoscintigraphy but others report up to 45% of cases. Controversy relates to the technique of lymphatic mapping, safety of IMN SNB, the significance of positive IMN, and potential to impact survival. METHODS: Assessment of drainage rates from two unrelated nuclear medicine departments' databases. Review of related literature. RESULTS: High-resolution lymphoscintigraphy results in IMN drainage in one-third of breast cancers. There is a learning curve for the technique. In 1754 consecutive cases, internal mammary drainage occurred in 53% of medial tumors, 37% midline tumors and 24% of lateral tumors (overall 34%). Extended radical mastectomy series also demonstrate the (approximately) 1/3 ratio when comparing IMN positivity rates to axillary node positivity rates (18.8% : 48.3%) and in node-positive patients (31% : 100%). The management altering potential of IMN assessment and potential survival impact are discussed. CONCLUSIONS: IMN mapping gives information that alters management in up to one-third of cases. These rates of IMN drainage are reproducible and reflect lymphatic density and anatomy of the breast. A priority need exists to establish a collaborative clinical trial to clarify the value of IMN assessment.

Melanoma patient imaging in the era of effective systemic therapies.

Imaging plays a critical role in the current multi-disciplinary management of patients with melanoma. It is used for primary disease staging, surgical planning, and surveillance in high-risk patients, and for monitoring the effects of systemic or loco-regional therapies. Several different imaging modalities have been utilised in the past. Contemporary imaging practises vary geographically depending on clinical guidelines, physician preferences, availability and cost. Targeted therapies and immunotherapies have revolutionised the treatment of patients with metastatic melanoma over the last few years. With this have come new patterns of disease that were not observed after conventional therapies, and new criteria to assess therapeutic responses. In this article we review the role of imaging for patients with melanoma in the era of effective systemic therapies and discuss likely future developments.

Role of ischemia and infarction in late right ventricular dysfunction after atrial repair of transposition of the great arteries.

OBJECTIVES: This study was conducted to assess whether myocardial ischemia and/or infarction are involved in the pathogenesis of late right ventricular dysfunction in adult survivors of atrial baffle repair for transposition of the great arteries in infancy. BACKGROUND: The medium-term success of intraatrial baffle repair for transposition of the great arteries is good, with many patients surviving into adult life, but prognosis can be limited by progressive right ventricular dysfunction. We hypothesized that ongoing myocardial ischemia and/or infarction are important factors in the pathogenesis of this complication. Radionuclide techniques offer an opportunity to study both myocardial perfusion and concomitant ventricular wall motion. METHODS: Dipyridamole sestamibi single-photon emission computed tomography followed by rest sestamibi single-photon emission computed tomography was used to assess right ventricular myocardial perfusion, wall motion, wall thickening and ejection fraction in 22 adolescents/young adults who had undergone atrial baffle repair for simple transposition of the great arteries at median 6.7 (range 0.5 to 54) months of age. The patients were aged 10 to 25 (median 15.5) years; 19 in New York Heart Association class I, 2 in class II and 1 in class III. All were in a regular cardiac rhythm during the studies. The right ventricular tomographic images were examined in three parallel and two orthogonal planes, analyzed in 12 segments. RESULTS: Perfusion defects were evident in all patients in at least one segment, in either the rest or stress images. Twelve patients (55%) demonstrated fixed defects only, nine (41%) had fixed and reversible defects and one (4.5%) had reversible defects only. Concomitant wall-thickening abnormalities occurred in 83% of segments with fixed perfusion defects, mirrored by a reduction in wall motion in 91% of segments analyzed. Right ventricular ejection fraction was correlated with age (R = 0.62; p = 0.002), and with wall-thickening abnormalities (R = 0.60; p < 0.005). CONCLUSIONS: Reversible and fixed perfusion defects with concordant regional wall motion abnormalities occur in the right (systemic) ventricle 10 to 20 years after Mustard repair for transposition of the great arteries; this may be important in the pathogenesis of late right ventricular dysfunction in this group.

Noninvasive assessment of acute effects of nifedipine on rest and exercise hemodynamics and cardiac function in patients with aortic regurgitation.

The acute effects of nifedipine (20 mg sublingually) on hemodynamics and cardiac function were studied at rest and during supine bicycle exercise in 20 patients with aortic regurgitation. At rest, heart rate increased by 13%, systemic vascular resistance decreased by 34% and regurgitant index decreased by 17%. The change in systemic vascular resistance was related to its initial rest level (r = 0.82, p less than 0.001) and to the changes in forward cardiac output (r = 0.58, p less than 0.01) and regurgitant index (r = 0.60, p less than 0.01). Left ventricular end-diastolic and end-systolic volumes, stroke volume and ejection fraction were unchanged, whereas right ventricular ejection fraction increased. During exercise, nifedipine administration further increased heart rate by 8% and decreased systemic vascular resistance by 19%. Both forward stroke volume and forward cardiac output increased, but total left ventricular stroke volume was unchanged, resulting in a significant decrease in regurgitant index. Although left ventricular end-diastolic volume was slightly decreased, end-systolic volume did not increase; thus, ejection fraction was higher than that during control exercise (p less than 0.01). Right ventricular ejection fraction increased further. In aortic regurgitation, the acute administration of nifedipine improved cardiac performance and reduced regurgitation at rest and during exercise as a result of afterload reduction and increased heart rate. Whether these beneficial effects will occur during long-term therapy requires further investigation.

Thallium-201 scintigraphy in pediatric soft-tissue tumors.

UNLABELLED: Thallium-201 has been used as a tumor imaging agent in adults with lymphoma, brain tumors, thyroid carcinoma and bone sarcomas. The application of 201Tl in pediatric oncology has been very limited. METHODS: Whole-body 201Tl studies were incorporated into the imaging protocols of 45 children with solid soft-tissue tumors. Bone and 67Ga scans as well as 131I-MIBG scans for patients with neuroblastoma were obtained. RESULTS: Seventeen children with lymphoma, five with Hodgkin's disease and twelve with non-Hodgkin's lymphoma (NHL) were studied. All of the patients with Hodgkin's disease showed avid uptake of 201Tl and 67Ga. The six patients with B-cell NHL had positive 67Ga scans and four had positive 201Tl scans. There was variable uptake in T-cell and undifferentiated lymphoma with an overall sensitivity of 69% for 201Tl and 85% for 67Ga. In 14 patients with rhabdomyosarcoma, 10 (71%) had positive 201Tl scans and 11 (79%) had positive 67Ga images. Gallium and thallium scans detected lesions equally. There was poor uptake of 201Tl in the six children with neuroblastoma. Primary tumor and metastases were detected more readily with the bone and MIBG scans. Three children with Wilms' tumor had poor or no uptake on 201Tl images, two of three patients with histocytosis had no significant uptake and one patient had mild uptake of 201Tl. One patient with primitive neuroectodermal tumor had positive 201Tl and 67Ga images and one patient with a neurofibrosarcoma had negative 201Tl and 67Ga images. There was no correlation with histological types of tumor or disease staging. CONCLUSION: This study shows significant uptake of 201Tl in many pediatric solid soft-tissue tumors. Additional study is needed to determine 201Tl effects on treatment response and tumor viability. Also, more studies are needed to assess 201Tl delayed images to determine if there is more tracer concentration in the tumors.

Gallium and thallium scintigraphy in pediatric peripheral primitive neuroectodermal tumor (Askin tumor) of the chest wall.

A 3.5-yr-old child presented with a large thoracic mass which showed avid accumulation of 67Ga and 201Tl was studied. Histology showed a peripheral neuroectodermal tumor of the chest wall typical of the malignancy described as the Askin tumor. The 201Tl studies were a more accurate method of following tumor response to therapy than 67Ga scintigraphy.

Lymphoscintigraphy in high-risk melanoma of the trunk: predicting draining node groups, defining lymphatic channels and locating the sentinel node.

Lymphoscintigraphy was performed in 209 patients with high-risk melanoma of the trunk referred to the Sydney Melanoma Unit and considered for lymph node dissection. Lymphoscintigraphy accurately defined the draining lymph node groups and was 94% sensitive in detecting draining sites that contained metastases. When combined with the clinical finding of palpable lymph nodes, the sensitivity rose to 98%. Most patients showed lymph drainage to one or two node groups and only 22 patients showed drainage to 3 or more node groups. The major lymph channels could also be marked on the skin prior to incontinuity dissection. Most patients had multiple draining lymph channels and these often diverged significantly from each other in the path to the draining node group. The number and location of interval nodes could be determined and marked on the skin. These and the major lymph channels could thus be excised at the time of surgery. Unusual drainage patterns were sometimes seen; for example, three patients displayed a new lymph pathway with direct drainage from the back anteriorly to the para-aortic nodes. The location of the sentinel nodes in each draining lymph-node group could also be marked on the skin prior to surgery, enabling quick and accurate identification of this node, using the blue-dye technique if biopsy were to be performed. These findings lead us to recommend lymphoscintigraphy prior to wide local excision in patients with truncal melanoma who are candidates for surgery. Lymphoscintigraphy results will help plan surgery and lead to minimum surgical intervention, consistent with effective surgical management.

Patterns of abnormality on bone scans in acute childhood leukemia.

Bone scintigraphy is not performed routinely in the diagnostic work-up of children with leukemia; however, the initial diagnosis of childhood leukemia is often difficult to make and may be delayed. Patients may present with fever and skeletal symptoms and, in such cases, bone scintigraphy may be requested in the early search for a diagnosis. Recognition of the potential scintigraphic abnormalities that result from leukemic infiltration of bone and bone marrow will often facilitate an early diagnosis of leukemia. Bone scans also play a role in detecting osteomyelitis in the immunosuppressed leukemic child with fever and bone pain. This article presents four patients illustrating the salient features of bone scintigraphy in these clinical settings.

Exercise thallium imaging: location of perfusion abnormalities in single-vessel coronary disease.

Exercise-induced thallium defects were segmentally analyzed in four standard views (anterior, 40 degrees left anterior oblique, 60 degrees left anterior oblique, and left lateral) and correlated with the arteriographic findings in 49 patients with single-vessel disease (> 70% diameter narrowing). Defects in the septal (SEPT), anteroiseptal (ANT SEPT), and anterior (ANT) segments correlated (p < 0. 0005) with stenosis of the left anterior descending coronary artery (LAD). For LAD disease the ANT SEPT segment had the highest sensitivity (84%) and specificity (100%). Defects in the inferior (INF), posteroinferior (POST INF), and posterior (POST) segments correlated (p < 0.0005) with either right (RCA) or circumflex (LCX) stenosis. For RCA or LCX disease, the POST segment had the highest sensitivity (82%) and specificity (100%). The site of single-vessel coronary artery disease can be accurately predicted noninvasively by segmental analysis of thallium images in four anatomical projections.

A model for the radionuclide measurement of ascitic fluid volumes.

Technetium-99m phytate colloids formed in vitro and in vivo were examined as radioindicators for estimation of the volume of third-space fluid in an ovarian ascites model using C3HeB/FeJ mice. In double-label experiments, the accuracy of the colloids for dilution analysis was found to be equal or superior to that of I-125 HSA. Sampling times 3--5 min after intraperitoneal administration were found to produce the best volume estimates. Four needle-stopcock assemblies inserted sequentially into the quadrants of the peritoneal cavity were used for administration and sampling of the radioindicators. The stopcocks could be closed to prevent leakage of ascitic fluid during the procedure. In contrast to radiolabeled albumin, Tc-99m phytate colloids have clinical use for simultaneous imaging of radiotracer migration to assess potential occlusion of diaphragmatic lymphatics by neoplastic cells, and for dilution analysis to estimate volume of ascitic fluid.

Gallium-67 and technetium-99m-methylene diphosphonate skeletal scintigraphy in determining prognosis for children with stage IV neuroblastoma.

Thirty-five children (aged 0-9 yr) who had presented with Stage IV neuroblastoma were studied to see if avidity for 67Ga or 99mTc-methylene diphosphonate (MDP) uptake in both primary and secondary sites at diagnosis conferred any prognostic significance. Twenty-three percent of the patients were disease free and off treatment at the time of study. Crude survival did not differ between groups. Duration of survival and the likelihood of completing treatment were related to the scintigraphic appearance at the time of diagnosis, after adjustment for potential confounding effects, using Cox's proportional hazards regression and multiple logistic regression. After adjustment for confounding influences, neither 67Ga avidity nor uptake of 99mTc-MDP was associated with a significantly worse prognosis, both in terms of adjusted survival and likelihood of completing treatment. Patients with 67Ga-avid scans at diagnosis did not demonstrate significantly worse survival (HR 1.47, 95% CI 0.43-5.11) than those without 67Ga avidity. They were somewhat less likely to complete treatment (OR 0.23, 95% CI 0.03-1.63), but this did not reach statistical significance. Similarly, although patients with 99mTc-MDP positive scans demonstrated somewhat worse survival (HR 2.47, 95% CI 0.45-13.54), this result did not reach statistical significance, nor were they less likely to complete treatment (OR 0.69, 95% CI 0.07-6.67) than those with 99mTc-MDP negative scans. Uptake of 99mTc-MDP into extraosseous sites was also not associated with worse survival (HR 1.45, 95% CI 0.58-3.62) nor with decreased likelihood of completing treatment (OR 0.78, 95% CI 0.12-5.09). Other than indicating disease stage, these results do not support the hypothesis that the scintigraphic appearance at diagnosis confers prognostic information in children with advanced neuroblastoma.

Mammary lymphoscintigraphy in breast cancer.

UNLABELLED: Lymphoscintigraphy has previously been used to define lymph drainage patterns and locate sentinel lymph nodes, prior to surgery, in patients with cutaneous melanoma. The aim of this study was to apply this technique to patients with breast cancer using intramammary injections placed around the primary tumor in the breast. METHODS: Lymphoscintigraphy using 99mTc-labeled antimony sulphide colloid was performed in 34 patients with a suspected primary breast cancer. Images were recorded immediately and at 2.5 hr using a LFOV digital gamma camera. Sentinel lymph node location was marked when possible. RESULTS: Lymphatic drainage patterns were successfully recorded in all but three patients. Lymph drainage was to the axillary, internal mammary, supraclavicular and, in one patient, infraclavicular node fields in various combinations but always on the same side of the body as the breast tumor. There was unexpected drainage across the center line of the breast to axillary or internal mammary nodes in 32% of patients with inner or outer quadrant lesions. Direct drainage to supraclavicular or infraclavicular nodes occurred in 20% of upper quadrant lesions. Drainage to the ipsilateral axilla occurred in 85% of patients, where a single sentinel node was seen in all cases. CONCLUSION: Intramammary lymphoscintigraphy can be used to define the lymphatic drainage patterns of individual breast cancers. The surface location of sentinel lymph nodes in the draining node fields can be marked and in the axilla their depth can be measured. It should therefore be possible to use lymphoscintigraphy, along with a blue dye injection technique or the gamma probe at surgery, to locate sentinel lymph nodes in patients with breast cancer.

Lymphatic drainage to triangular intermuscular space lymph nodes in melanoma on the back.

METHODS: Lymphoscintigraphy with 99mTc-antimony sulphide colloid was performed on patients with cutaneous melanoma of the back to define draining node fields and sentinel nodes before surgery. RESULTS: One patient was found to have drainage from the back to sentinel lymph nodes in the triangular intermuscular spaces bilaterally, above and lateral to the scapula. Subsequently, drainage to this node field has been found in 26% of 42 consecutive patients who have had lymphoscintigraphy performed for melanoma on the back. CONCLUSION: When performing lymphoscintigraphy to locate draining node fields and sentinel nodes in patients with melanoma on the back, it is important to look for drainage to the triangular intermuscular space node field by obtaining posterior and lateral scans. Any sentinel lymph nodes found in this field should be marked prior to surgery in the same way as nodes in other node fields are delineated so that they may be removed at surgery.

Variability in the interpretation of dimercaptosuccinic acid scintigraphy after urinary tract infection in children.

UNLABELLED: Technetium-99m-dimercaptosuccinic acid (DMSA) scintigraphy is a frequently used diagnostic test in pediatric practice to assess the presence and severity of renal damage. Most commonly it is performed after urinary tract infection. The aim of this study was to investigate the variability in the interpretation of DMSA scans by pediatric nuclear medicine physicians in this clinical setting. METHODS: We selected all 441 scans from children with first-time urinary tract infection who presented between 1993 and 1995 to a pediatric casualty department and who are participants in a prospective cohort study. Two hundred and ninety-four scans were performed at a median time of 7 days after diagnosis, and 147 scans were from children who were free from further infection over a 1-yr follow-up period. Two experienced nuclear medicine physicians independently interpreted the 441 scans according to whether renal damage was present or absent and using the modified 4-level grading system for DMSA abnormality of Goldraich. Apart from being informed that urinary tract infection was the indication for DMSA scintigraphy, no other clinical information was given to the nuclear medicine physicians. The indices of variability used were the percentage of agreement and the kappa statistic. For the grading scale used, both measures were weighted with integers representing the number of categories from perfect agreement. Disagreement was analyzed for children, kidneys and kidney zones. RESULTS: There was agreement in 86% (kappa = 69%) for the normal-abnormal DMSA scan dichotomy, and the weighted agreement was 94% (weighted kappa = 82%) for the grading of abnormality. Disagreement of DMSA scan interpretation of > or =2 grades was present in three cases (0.7%). The same high level of agreement was present for patient, kidney and kidney zone comparisons. Agreement was not influenced by age or timing of scintigraphy after urinary tract infection. CONCLUSION: Two experienced nuclear medicine physicians showed good agreement in the interpretation of DMSA scintigraphy in children after urinary tract infection and using the grading system of Goldraich.

Radionuclide left ventriculography with the slant hole collimator.

A 30 degrees slant-hole collimator was used during radionuclide ventriculography of the cardiac blood pool to improve imaging of the heart in both the modified left anterior oblique (MLAO) and right anterior oblique (RAO) views. In the MLAO view, with the holes slanted caudally, good separation between the left atrium and left ventricle was achieved, and the septum was displayed without foreshortening. In the RAO view with the collimator flat against the chest there was better resolution of the cardiac apex. The results of ejection fraction and wall motion analysis in these patients correlated well with contrast ventriculography (r=0.94). Combination of the slant-hole collimator, in vivo red blood cell labeling with stannous pyrophosphate, simultaneous collection of all phases of the cardiac cycle, and cine mode display, provide a practical system for the noninvasive measurement of left ventricular performance parameters.

Localization of coronary artery disease with exercise electrocardiography: correlation wit thallium-201 myocardial perfusion scanning.

In 61 patients with single vessel coronary artery disease (70 percent or greater obstruction of luminal diameter in only one vessel) and no previous myocardial infarction, the sites of ischemic changes on 12 lead exercise electrocardiography and on thallium-201 myocardial perfusion scanning were related to the obstructed coronary artery. The site of exercise-induced S-T segment depression did not identify which coronary artery was obstructed. In the 37 patients with left anterior descending coronary artery disease S-T depression was most often seen in the inferior leads and leads V4 to V6, and in the 18 patients with right coronary artery disease and in the 6 patients with left circumflex artery disease S-T depression was most often seen in leads V5 and V6. Although S-T segment elevation was uncommon in most leads, it occurred in lead V1 or a VL, or both, in 51 percent of the patients with left anterior descending coronary artery disease. A reversible anterior defect on exercise thallium scanning correlated with left anterior descending coronary artery disease (probability [p] less than 0.0001) and a reversible inferior thallium defect correlated with right coronary or left circumflex artery disease (p less than 0.0001). In patients with single vessel disease, the site of S-T segment depression does not identify the obstructed coronary artery; S-T segment elevation in lead V1 or aVL, or both, identifies left anterior descending coronary artery disease; and the site of reversible perfusion defect on thallium scanning identifies the site of myocardial ischemia and the obstructed coronary artery.

Abnormal left ventricular response to isometric exercise in pure, isolated aortic regurgitation: beneficial effects of nifedipine.

To examine the effects of nifedipine on the left ventricular (LV) functional response to isometric exercise in patients with aortic regurgitation (AR), 20 patients with isolated, moderate to severe AR performed 3 minutes of handgrip exercise at 33% of their maximal voluntary contraction, before and after administration of 20 mg of sublingual nifedipine. Although handgrip exercise produced similar increases in heart rate and systolic blood pressure before and after nifedipine treatment, heart rate was higher and systolic blood pressure lower with handgrip exercise during nifedipine treatment. LV end-diastolic volume index was not different during the control period and nifedipine handgrip exercise, but the increase in end-systolic volume index was smaller and the ejection fraction was higher during nifedipine handgrip exercise. Nifedipine reduces afterload and ameliorates handgrip exercise-induced LV dysfunction in patients with AR.

Preoperative and postoperative technetium-99m pyrophosphate myocardial scintigraphy in the assessment of operative infarction in coronary artery surgery.

The incidence of operative myocardial infarction was assessed by electrocardiogram (ECG) and technetium-99m pyrophosphate (99mTc-PyP) myocardial scintigrams in 89 consecutive patients undergoing coronary artery bypass grafting (CABG). Myocardial scintigrams were performed on the day before operation and repeated 2 to 3 days postoperatively. All patients survived operation, with three in-hospital deaths not related to myocardial infarction (mortality rate 3 percent). Operative infarction was assessed to have occurred in four of 89 patients (4 percent). Two had new Q waves and positive scintigrams; one, major ST-T wave changes and a positive scintigram; and the fourth, new Q waves without a positive scintigram. Three further patients (3 percent) had Q waves and positive scintigrams postoperatively, but myocardial infarction was evolving before anesthesia and operation. Twenty-seven of 89 patients (30 percent) were found to have abnormal scintigrams preoperatively. In two patients, both operated upon with evolving myocardial infarction, the scintigram was worse postoperatively. In 13 patients the scintigram was improved after operation. In 12 patients (13 percent) the abnormal preoperative scintigram was unchanged after operation. Preoperative and postoperative myocardial scintigrams and ECG's must be compared to assess the incidence of operative myocardial infarction in patients undergoing CABG.