Fatores associados a anormalidades na cintilografia de perfusão miocárdica de pacientes diabéticos / Factors associated with abnormalities on myocardial perfusion scintigraphy in diabetic patients

O diabetes melito é o maior fator de risco para doença arterial coronariana. Além da longa duração de diabetes, outros fatores, como presença de doença arterial periférica e tabagismo são fortes preditores para anormalidades na cintilografia de perfusão do miocárdio. O objetivo deste estudo foi avaliar o impacto dos fatores de risco de pacientes diabéticos nos resultados da cintilografia de perfusão do miocárdio e comparar com os resultados de pacientes não diabéticos em uma clínica de medicina nuclear. Foi realizado um estudo transversal retrospectivo por meio da análise de prontuários de pacientes que realizaram cintilografia miocárdica no período de 2010 a 2019. Foram avaliados 34.736 prontuários. Analisando a fase de estresse da cintilografia de perfusão do miocárdio, os portadores de diabetes melito precisaram receber estímulo farmacológico duas vezes mais que os não diabéticos para sua realização. Também foram avaliados fatores que tivessem impacto negativo no resultado da cintilografia de perfusão do miocárdio, e foi visto que o diabetes melito (33,6%), a insulinoterapia (18,1%), a hipertensão arterial sistêmica (69,9%), a dislipidemia (53%), o sedentarismo (83,1%), o uso de estresse farmacológico (50,6%), a dor torácica típica (8,5%) e a angina limitante durante o teste (1,7%) estiveram associados significativamente (p<0,001) a anormalidades neste exame. (AU)

Diabetes mellitus (DM) is the greatest risk factor for coronary artery disease. In addition to a long duration of diabetes, the presence of peripheral arterial disease and smoking are strong predictors of abnormalities on myocardial perfusion scintigraphy (MPS). This study aimed to assess the impact of risk factors in diabetic patients on MPS results and compare them with those of non-diabetic patients in a nuclear medicine clinic. A retrospective cross-sectional study was performed through the analysis of the medical records of patients who underwent MPS in 2010­2019. A total of 34,736 medical records were evaluated. Analyzing the stress phase of MPS, DM patients required two-fold more pharmacological stimulation than non-diabetic patients for MPS. Factors that negatively impact the MPS results were also evaluated, and DM (33.6%), insulin therapy (18.1%), systemic arterial hypertension (69.9%), dyslipidemia (53%), sedentary lifestyle (83.1%), use of pharmacological stress (50.6%), typical chest pain (8.5%), and limiting angina during the test (1.7%) were significantly associated (p < 0.001) with test abnormalities. (AU)

Comparative Analysis of Lung Perfusion Scan and SPECT/CT for the Evaluation of Functional Lung Capacity / 대한핵의학회잡지

PURPOSE: This study aimed to compare lung perfusion scan with single photon emission computed tomography/computed tomography (SPECT/CT) for the evaluation of lung function and to elucidate the most appropriate modality for the prediction of postoperative lung function in patients with lung cancer.METHODS: A total of 181 patients underwent Tc-99m macroaggregated albumin lung perfusion scan and SPECT/CT to examine the ratio of diseased lung and diseased lobe. Forty-one patients with lung cancer underwent both preoperative and postoperative pulmonary function tests within 1 month to predict postoperative pulmonary function. Predicted postoperative forced expiratory volume in 1 s (ppoFEV₁) was calculated by the % radioactivity of lung perfusion scan and SPECT, and the % volume of the residual lung, assessed on CT.RESULTS: The ratios of diseased lung as seen on lung perfusion scan and SPECT showed significant correlation, but neither modality correlated with CT. The ratios of the diseased lung and diseased lobe based on CT were higher than the ratios based on either perfusion scan or SPECT, because CT overestimated the function of the diseased area. The lobar ratio of both upper lobes was lower based on the perfusion scan than on SPECT but was higher for both lower lobes. Actual postoperative FEV₁ showed significant correlation with ppoFEV₁ based on lung perfusion SPECT and perfusion scan.CONCLUSIONS: We suggest SPECT/CT as the primary modality of choice for the assessment of the ratio of diseased lung area. Both perfusion scan and SPECT/CT can be used for the prediction of postoperative lung function.

Fibrosing Mediastinitis: a Rare Cause of Unilateral Absent Lung Perfusion on a V/Q Scan / 대한핵의학회잡지

We report a case of a 29-year-old female with a history of asthma, post-partumARDS, and pulmonary hypertension who presents with severe shortness of breath. The patient describes her shortness of breath as progressive over the past 10 years. Chest radiography and CT angiography of the thorax showed findings consistent with fibrosing mediastinitis with severe stenosis of the left main pulmonary artery. This resulted in appearance of unilateral absent left lung perfusion on quantitative Tc-99-MAA perfusion and Xe-133 ventilation (V/Q) scan.

Estudio de la perfusión pulmonar posterior al cierre percutáneo del conducto arterioso permeable utilizando el dispositivo Amplatzer Duct Occluder en niños / Lung perfusion studies after percutaneous closure of patent ductus arteriosus using the Amplatzer Duct Occluder in children

Objetivo: La reducción en la perfusión pulmonar se ha descrito tras el cierre percutáneo del conducto arterioso permeable con varios dispositivos. Evaluamos la perfusión pulmonar posterior al cierre percutáneo del conducto arterioso con el dispositivo Amplatzer Duct Occluder utilizando la gammagrafía pulmonar de perfusión. Métodos: Treinta pacientes con oclusión transcatéter exitosa del conducto arterioso permeable utilizando el dispositivo Amplatzer Duct Occluder fueron incluidos en este estudio. La gammagrafía pulmonar de perfusión se realizó 6 meses después del procedimiento. Las velocidades de flujo máximo y la protrusión del dispositivo fueron analizadas por ecocardiografía Doppler. Una perfusión pulmonar izquierda < 40% se consideró anormal. Resultados: El implante del dispositivo fue exitoso en todos. La media de perfusión hacia el pulmón izquierdo fue de 44.7 ± 4.9% (37.8-61.4). Cinco pacientes (16.6%) mostraron disminución en la perfusión pulmonar izquierda. Tanto la edad y el peso bajo, así como la longitud del conducto arterioso y la relación diámetro mínimo y máximo con la longitud del conducto arterioso fueron estadísticamente significativos en los pacientes con anomalías de la perfusión pulmonar. Se observó protrusión del dispositivo en 6 pacientes con una velocidad de flujo máximo mayor en la arteria pulmonar izquierda. Conclusión: La perfusión pulmonar izquierda puede comprometerse tras el cierre percutáneo del conducto arterioso con el Amplatzer Duct Occluder. El aumento en la velocidad de flujo en el origen de la arteria pulmonar izquierda puede ser un pobre indicador de la reducción en la perfusión pulmonar y puede ocurrir en ausencia de protrusión del dispositivo.

Objective: The closure of patent ductus arteriosus with multiple devices has been associated with a reduction in lung perfusion. We evaluated the pulmonary perfusion after percutaneous closure of patent ductus arteriosus with the Amplatzer Duct Occluder device using perfusion lung scan. Methods: Thirty patients underwent successful percutaneous patent ductus arteriosus occlusions using the Amplatzer Duct Occluder device were included in this study. Lung perfusion scans were preformed 6 months after the procedure. Peak flow velocities and protrusion of the device were analyzed by Doppler echocardiography. A left lung perfusion < 40% was considered abnormal. Results: The device implantation was successful in all patients. Average perfusion of left lung was 44.7 ± 4.9% (37.8-61.4). Five patients (16.6%) showed decreased perfusion of the left lung. Age, low weight, the length of the ductus arteriosus and the minimum and maximum diameter/length of the ductus arteriosus ratio were statistically significant in patients with abnormalities of lung perfusion. It was observed protrusion the device in 6 patients with a higher maximum flow rate in the left pulmonary artery. Conclusion: The left lung perfusion may be compromised after percutaneous closure of patent ductus arteriosus with the Amplatzer Duct Occluder. The increased flow velocity in the origin of the left pulmonary artery can be a poor indicator of reduction in pulmonary perfusion and can occur in the absence of protrusion of the device.

The applications study of dual-source CT perfusion scan in normal pancreas / 实用放射学杂志

Objective To investigate perfusion imaging and parameters of normal pancreas by dual-source CT and to evaluate the appropriate perfusion imaging scan.Methods Sixty-six subjects with normal pancreas underwent low-dose pancreatic perfusion and plain scan.CT images were sent to a separate workstation via a network.The blood flow (BF)and blood volume (BV)of pancreas head,body and tail were measured using the VPCT Body software and analyzed by one-way ANOVA.Then the time-density curve of pancreas was drawn,and the enhancement peak time and the corresponding CT value were also measured.Results The average BF values of pancreas head,body and tail were (1 1 6.09 ± 31.83)mL·100 g-1 ·min-1 ,(1 1 9.72±32.50)mL·100 g-1 ·min-1 , (1 14.65±31.42)mL·100 g-1 ·min-1 ,and the mean BV values were (29.83 ±1 9.07)mL/100 g,(30.39 ± 1 9.38)mL/100 g, (28.82±1 9.22)mL/100 g,respectively.The perfusion parameters in different pancreatic parts were not statistically different.The mean enhancement peak time was (27.92 s±4.52)s,(28.02±5.34)s in pancreas head,(27.40±4.36)s in pancreas body,(27.34±4.57)s in pancreas tail.On plain image,the average CT value of pancreas was (41.43±5.88)HU.However,on enhanced image,the mean CT value was (95.96±18.44)HU in normal pancreas [(96.73±19.71)HU in pancreas head,(98.45±17.52)HU in body,(92.69±18.1 7)HU in tail].Conclusion The perfusion parameters including blood flow and blood volume in pancreatic head,body and tail are identical. The mean enhancement peak time is (27.92±4.52)s,and the corresponding enhancement CT value is (95.96±18.44)HU.

Comparing planar and SPECT lung perfusion scans in the diagnosis of pulmonary embolism

The non-specificity of symptoms of pulmonary embolism (PE) makes imaging studies essential. The ventilation-perfusion lung scan (VQ) is the most frequently done nuclear medicine test for PE but the length of imaging time is inconvenient to the patient. The purpose of this study is to evaluate planar and SPECT lung perfusion scans interpreted using the PISA-PED criteria. In determining the sensitivity, specificity, positive and negative predictive values of the two imaging techniques, we also aim to present a simplified imaging method that foregoes the ventilation scan in the diagnosis of PE. This could lead to a change in the standard VQ scintigraphy protocol being used by nuclear medicine centers in the Philippines. This is a prospective study wherein fourteen patients suspected of having PE underwent planar and SPECT perfusion scans and CT pulmonary angiography, which was used as the gold standard for diagnosing PE. Planar and SPECT specificities and positive predictive values were the same at 100%. The sensitivity, negative predictive value, and accuracy of SPECT (85.7%,87.5%,92.8%, respectively) were all higher than planar scans (71.4%, 77.8%, 85.7%, respectively. A SPECT perfusion scan is superior to a planar perfusion scan in detecting pulmonary embolism. This implies that the standard ventilation-perfusion scan used by nuclear medicine centers in the country can be simplified. A ventilation scan can be omitted.

Is routine screening examination necessary for detecting thromboembolism in childhood nephrotic syndrome? / 소아과

PURPOSE: The incidence of thromboembolic episodes in children with nephrotic syndrome (NS) is low; however, these episodes are often severe. Moreover, both pulmonary thromboembolism (PTE) and renal vein thrombosis (RVT) rarely show clinical symptoms. This study was performed to determine the benefits of routine screening in the detection of thrombosis in childhood NS. METHODS: Among 62 children with nephrotic syndrome, a total of 54 children (43 males, 11 females) were included in this study. When the patients experienced their first NS episode, we performed renal Doppler ultrasonography in order to detect RVT. To rule out the possibility of PTE, a lung perfusion scan was performed. Computed tomographic (CT) pulmonary angiography was recommended to patients who showed possible signs of PTE. All patients were evaluated for clinical signs of thrombosis, biochemical indicators of renal disease, as well as clotting and thrombotic parameters. RESULTS: RVT or related clinical symptoms were not observed in any children. Based on the findings of the lung perfusion scans, 15 patients (27.8%) were observed with as a high probability of PTE. We were able to perform a CT pulmonary angiography only on 12 patients, and 5 patients were diagnosed with PTE (prevalence 8.1%). The serum fibrinogen level in the group with PTE was significantly higher (776.7+/-382.4 mg/dL, p<0.05) than that in the group without PTE, and other parameters were not significantly different between each group. CONCLUSION: Further studies are required for clarifying the role of renal Doppler ultrasonography for the detection of RVT in NS. Children with NS who developed non-specific respiratory symptoms should be evaluated for the diagnosis of PTE. In the management of NS, a lung perfusion scan should be performed at the time of the initial episode of NS regardless of the pulmonary symptoms, since patients having PTE are either often asymptomatic, or present with nonspecific symptoms.

Study of SCTPA and V/Q scan in diagnosis of pulmonary thromboembolism / 中国实用内科杂志

Objective To evaluate the clinical value of SCTPA and pulmonary V/Q scan in the diagnosis of pulmonary thromboembolism(PTE).Methods Ninety-two patients suspected of having PTE received SCTPA,pulmonary V/Q scan,and other related examinations.Results Thirty-five patients were diagnosed as having PTE in 92 patients investigated,30 cases were revealed by SCTPA,and 20 cases revealed by pulmonary V/Q scan.The area under ROC curve of SCTPA by V/Q scan and combination examination was 0.922,0.824,and 0.933,respectively(P

A Case of Pulmonary Embolism After Cesarean Delivery / 대한산부인과학회잡지

During the past 50 years, the maternal mortality ratio has decreased dramatically. The leading causes of maternal deaths were pulmonary embolism, the complications of the pregnancy-induced hypertension, hemorrhage, the complications of the ectopic pregnancy and infection. Pulmonary embolism is one of the most fatal maternal complications that abruptly happen and rapidly progress, and has been a major cause of maternal death recently. Early detection of pulmonary embolism is difficult, because there is not any specific clinical symptoms and signs. We have experienced a case of a fatal pulmonary embolism which was diagnosed by lung perfusion scan on postoperative 1 day after cesarean delivery and managed with heparin therapy. We report this case with a brief review of literatures.

Stenosis of Individual Pulmonary Veins

Pulmonary hypertension may be associated with variable conditions such as the hyperkinetic state or pulmonary vascular obstruction. In these, stenosis of the individual pulmonary veins without any cardiac or vascular malformation is very rare. We experienced stenosis of individual pulmonary veins in a 10 months old boy who was admitted with recurrent dyspnea and cyanosis and then underwent angiogram and a lung perfusion scan.

Prediction of Post-operative Cardiopulmonary function By Perfusion Scan / 결핵

BACKGROUND: Perfusion scans are accurate predictors of postoperative lung function. There are few previous studies aimed at predicting the postoperative exercise capacity using the perfusion scanning and those that did reported contradictory results. METHOD: We prospectively studied the preoperative spirometric, exercise tests and perfusion scans from in 49 consecutive patients who were admitted to Inha University Hospital with surgically resectable lung cancer from Jan. 1998 to Jun. 1999 29 patients who had any condition affecting the lung function and exercise capacity, or refused a surgical resection or a follow-up study were excluded. Spirometric and exercise tests were performed 6 months after operation in 20 patients. RESULTS: The predicted postoperative FEV1, FVC and TLC correlated well with the following corresponding postoperative values : γs and p value, 0.809 and 0.000 for the FEV1 ; 0.895 and 0.000 for the FVC ; 0.741 and 0.006 for the TLC, respectively. The measured postoperative exercise values were slightly higher than the postoperative exercise values predicted, VO(2max) and Wr(max), were as 112% of VO(2max) predicted and 119% of WR(max) predicted. The change in FEV1, FVC and TLC had a weak correlation with the change in VO(2max) and WR(max). CONCLUSION: The perfusion scan was a useful tool for predicting the postoperative exercise capacity. However, they had a tendency to underestimate the exercise capacity, especially in the patients who had a pneumonectomy. A weak correlation between the change in lung function and exercise capacity was obseved.

A Case of Pulmonary Embolism After Cesarean Delivery / 대한산부인과학회잡지

Pulmonary Embolism, one of the causes of maternal death, is a life threatening disease that needs early and accurate diagnosis. We have exprerienced a case of a fatal pulmonary embolism which was diagnosed by lung perfusion scan on the postoperative 1 day after cesarean delivery and was managed with heparin therapy. We present this case with a brief review of literatures.

The Usefulness of Echocardiographic Severity Index for Prediction of Severity of Pulmonary Embolism

BACKGROUND: Pulmonary embolism is associated with varying degrees of pulmonary vascular obstruction. This study was undertaken to establish whether the extent of perfusion defect in lung scintigraphy can be predicted from analysis of echocardiographic measurements in patients with pulmonary embolism. METHODS: We retrospectively studied 28 patients who presented with clinical evidence of pulmonary embolism. In order to compare the extent of perfusion defect in lung scintigraphy, we devised a scoring system (echocardiographic severity index, ESI) for various echocardiographic parameters, which include right ventricle size, area, shape, systolic function, and pulmonary artery pressure. [ESI=sum of scores/number of parameters measured]. RESULTS: The mean values (+/-SD) of each parameter were as follow; right ventricular end-diastolic dimension (RVedD), 34.5+/-5.7 mm; LVedD, 40.9+/-5.2 mm; ratio of RVedD to LVedD, 0.87+/-0.2; right ventricular end-diastolic area (RVedA), 24.7+/-9.5 cm2; right ventricular end-systolic area (RVesA), 17.8+/-7.8 cm2; fractional area change, 28.8+/-9.7%; angle between IVS and RV, 96.0+/-14.8degrees; RV hypokinesia, absence or mild in 29%, moderate in 50%, severe in 21%; TR grade, absence or mild in 25%, moderate in 43%, severe in 32%; pulmonary artery systolic pressure, 50 mmHg 11% of patients. The echocardiographic severity index (ESI) in patients with pulmonary embolism was 0.52+/-0.24, and the perfusion defect score was 0.21+/-0.14. There was a close correlation between the ESI and the extent of perfusion defect (r=0.622, p<0.01). CONCLUSION: The echocardiographic severity index may reflect the extent of the perfusion defects in patients with pulmonary embolism, therefore it is potentially applicable in clinical practice for evaluating patients with pulmonary embolism and furthermore in their follow-up over a period of time.

Effect of Unilateral Diaphragmatic Palsy on Lung Perfusion in Rabbit Model

BACKGROUND: In congenital heart disease, the lung perfusion through stenosed pulmonary artery is usually decreased. And this decrement of lung perfusion also occurs with diaphragmatic palsy after the operation of congenital heart disease. It is difficult to delineate the amount of lung perfusion in case of combination of pulmonary artery stenosis and diaphragmatic palsy. We examined the change of lung perfusion after the induction of diaphragmatic palsy in rabbits. METHODS: We dissected left phrenic nerves in 20 rabbits to induce left diaphragmatic palsy. The lung perfusion scan was performed with 99mTc-MAA and the movement of diaphragm was examined with fluoroscopy. They were performed as baseline data and on 3rd and 10th day postoperatively. The amount of left lung pefusion before and after diaphragmatic palsy was compared and analysed in 12 rabbits which definitely had diaphragmatic palsy. RESULTS: Weight of the rabbits was 1.65+/-0.26 kg. Left lung perfusion percent was 45.93+/-6.42% before operation and these were 32.48+/-6.09% and 37.62+/-3.39% on the 3rd and 10th postoperative day, respectively. Left lung perfusion was significantly decreased just after diaphragmatic palsy but it was not changed thereafter. The decrement of lung perfusion was not affected by the body weight. The decreased amount of left lung perfusion was reciprocally correlated with the body weight of the rabbits on the postoperative 3rd day but not 10th day. CONCLUSION: Left lung perfusion percent of the rabbits was decreased 7% with the induction of diaphragmatic palsy and the decreased amount was reciprocally correlated with the body weight just after the diaphragmatic palsy was induced.

The effectiveness of spiral computed tomography as a diagnostic tool in pulmonary embolism: Comparison of spiral CT with Ventilation-perfusion scan / 결핵

BACKGROUND: With variable symptoms and nonspecific radiographic appearances, pulmonary embolism (PE) is a frequent and often undiagnosed cause of mortality and morbidity. The Prospective Investigation of Pulmonary Embolism Diagnosis (PIOPED) study suggested that the majority of patients undergoing ventilation-perfusion (V-Q) scan would require additional studies to establish or to exclude the diagnosis of PE. Pulmonary angiography has been regarded as gold standard for diagnosis of PE. However, it is an invasive procedure that may be associated with significant notable mo rbidity and mortality. Thus, availability of an accurate, noninvasive screening examination is highly desirable. METHOD: From October 1994 to February 1997, twenty patients (male 13, female 7, range 23-91 years, median 58 years) who were suspected as pulmonary embolism on the basis of clinical evidence and underwent the spiral volumetric computed tomography (spiral CT), were studied retrospectively to evaluate the effectiveness of spiral CT as a diagnostic tool in PE. RESULTS: PE could be excluded with spiral CT in 4 patients; diagnoses of these patients were lung cancer, pneumonia with lung abscess, bilateral pleural effusion due to congestive heart failure, nonspecific pulmonary abnormality retrospectively. One patient who disclosed high probability in V/Q scan, could be diagnosed as pneumonia with lung abscess and underlying emphysema with spiral CT. Among 4 patients who showed intermediate and low probability in V/Q scan, 3 patients could be confirmed as PE with spiral CT. Spiral CT were helpful in 3 patients, in whom V/Q scan could not be performed due to other reasons (e.g. night time, mechanical ventilation) to confirm the diagnosis of PE. Spiral CT could demonstrate embolus above lobar artery level in 11 patients, and up to segmental artery level in 5 patients. CONCLUSION: This study demonstrated that spiral CT could allow accurate demonstration of thrombotic clots in centrally localized embolism. Spiral CT could be effective, specific, noninvasive and useful diagnostic screening modality for the diagnosis of pulmonary embolism.

The effectiveness of spiral computed tomography as a diagnostic tool in pulmonary embolism: Comparison of spiral CT with Ventilation-perfusion scan / 결핵

BACKGROUND: With variable symptoms and nonspecific radiographic appearances, pulmonary embolism (PE) is a frequent and often undiagnosed cause of mortality and morbidity. The Prospective Investigation of Pulmonary Embolism Diagnosis (PIOPED) study suggested that the majority of patients undergoing ventilation-perfusion (V-Q) scan would require additional studies to establish or to exclude the diagnosis of PE. Pulmonary angiography has been regarded as gold standard for diagnosis of PE. However, it is an invasive procedure that may be associated with significant notable mo rbidity and mortality. Thus, availability of an accurate, noninvasive screening examination is highly desirable. METHOD: From October 1994 to February 1997, twenty patients (male 13, female 7, range 23-91 years, median 58 years) who were suspected as pulmonary embolism on the basis of clinical evidence and underwent the spiral volumetric computed tomography (spiral CT), were studied retrospectively to evaluate the effectiveness of spiral CT as a diagnostic tool in PE. RESULTS: PE could be excluded with spiral CT in 4 patients; diagnoses of these patients were lung cancer, pneumonia with lung abscess, bilateral pleural effusion due to congestive heart failure, nonspecific pulmonary abnormality retrospectively. One patient who disclosed high probability in V/Q scan, could be diagnosed as pneumonia with lung abscess and underlying emphysema with spiral CT. Among 4 patients who showed intermediate and low probability in V/Q scan, 3 patients could be confirmed as PE with spiral CT. Spiral CT were helpful in 3 patients, in whom V/Q scan could not be performed due to other reasons (e.g. night time, mechanical ventilation) to confirm the diagnosis of PE. Spiral CT could demonstrate embolus above lobar artery level in 11 patients, and up to segmental artery level in 5 patients. CONCLUSION: This study demonstrated that spiral CT could allow accurate demonstration of thrombotic clots in centrally localized embolism. Spiral CT could be effective, specific, noninvasive and useful diagnostic screening modality for the diagnosis of pulmonary embolism.

Clinical Characterization of Reverse Redistribution Pattern in 99mTC-Sestamibi Myocardial Perfusion Scan

BACKGROUND AND OBJECTIVES: Reverse redistribution pattern (RRP), that is defined as the worsening of the perfusion defect at rest image, can be observed in 99mTC-sestamibi (methoxy isobutyl isonitrile) myocardial scan with standard stress-rest protocol. This study was prepared to evaluate the prevalence and clinical characteristics of RRP in stress 99mTc-sestamibi myocardial scan. MATERIALS AND METHODS: We retrospectively reviewed 1304 images of 99mTC-sestamibi myocardial perfusion scan performed between January 1995 and June 1997, and scintigraphic findings were compared with clinical and angiographic data. RESULTS: The prevalence of RRP was 5.2%(68 of 1,304). RRP was noted in 6.0% (41 of 679) of the adenosine study and 4.3% (27 of 625) of the exercise study. The mean coronary artery stenosis at RRP territory was 51.5+/-38.9%. However, normal coronary artery at RRP territory was noted in 45.8% (11 of 24). There was no significant differences in luminal narrowing of coronary arteries, TIMI flow grade and LV wall motion between the patient with RRP positive and RRP negative at the infarct related artery territory. CONCLUSION: Reverse redistribution pattern on 99mTC-sestamibi myocardial SPECT does not seem to indicate the presence of significant coronary artery disease or patency of the infarct related arteries in the patients with acute MI.

The Assessment of Pulmonary Parenchymal Damage in Congenital Heart Disease using Lung Perfusion Scan

PURPOSE: In acyanotic congenital heart disease of children with left to right shunt, 99mTc- Macroaggregate albumin (MAA) was employed to determine the scintigraphic severity of pulmonary parenchymal damage. METHODS: These data of lung perfusion scan using 99mTc-MAA were compared with hemodynamic values obtained from cardiac catheterization. RESULTS: The mean Pulmonary arterial pressure (> or = 30mmHg), total pulmonary resistance (> or = 2 Wood unit) & ratio of pulmonary vascular resistance/systemic resistance (Rp/Rs > or = 0.2) were proportionally related to higher perfusion ratio of upper and lower lung field. The diagnostic values of perfusion ratio of upper & lower field of both lung (cut off value > or = 0.8) for pulmonary hypertension were as follows : 60-65% of sensitivity, 75-90% of specificity, 72-86% of positive predictive value & 68-69% of negative predictive value. The mottled perfusion defect was frequently found in patients with pulmonary hypertension (mean pulmonary arterial pressure > or = 30mmHg, Rp > or = 2 Wood unit). The degree of perfusion defect as indicator of severe pulmonary parenchymal damage was utilized clinically as determinator of operability and morbidity for acyanotic shunt lesions perioperatively. CONCLUSION: The scintigraphic severity determined by 99mTc-MAA lung perfusion scan could be valid for evaluating the extent of pulmonary parenchymal damage in acyanotic congenital heart disease complicated by pulmonary hypertension.

Localization of Ischemic Area with Exercise Electrocardiography in Angina Pectoris: Correlation with 99mTc-MIBI Myocardial Perfusion Scanning

BACKGROUND: The purpose of the study was to determine the value of exercise electrocardiography in predicting the area of myocardial ischemia. METHOD: Seventy-six anginal patients with a perfusion defect in one vessel territory on exercise 99mTc-MIBI myocardial perfusion scan were studied. Each patient underwent exercise electrocardiograhy using modified Bruce protocol. Exercise electrocardiography was interpreted as abnormal when the horizontal or downsloping depression in ST segment was 0.1 mV or greater at 80 msec after the J point during exercise. Forty-eight patients had exercise induced ST-segment depression. RESULT: Twenty-five patients had exercise induced ST-segment depression in single lead-group and 23 patients had in multiple lead-groups. In 18 patients (18/23) with exercise induced ST-segment depression in multiple lead-groups, the perfusion defect involved the apical area on myocardial perfusion scanning and in 21 patients (21/25) with ST-segment depression in single lead-group, the perfusion defect did not involve the apical area. In patients without perfusion defect in the apical area, ST-segment depression in anterior lead-group (V1 to V4) was associated with myocadial perfusion defects in left anterior descending artery territories in five of five cases (100%), ST-segment depression in lateral lead-group (I, aVL, V5, V6) was associated with defects in left circumflex artery territories in six of six cases (100%), and ST-segment depression in inferior lead group (II, III, aVF) was associated with defects in right coronary artery territories in nine of ten (90%) (p<0.01). In patients with perfusion defect in the apical area, exercise induced ST-segment depressions were observed in multiple lead-groups (18/22). CONCLUSION: ST-segment depression on 12 lead exercise electrocardiography was a good predictor of the site of myocadial ischemia in anginal patients with single vessel territory ischemia when ST-segment depression developed in single lead group. However, ST-segment depressions in mutiple lead-groups suggested that the perfusion defect involved the apical area and did not predict the site of myocardial ischemia.