Vieira NW,Pereira Neto WC, Rabello AC, Pereira Filho WCP, Loures JBL, Muniz AJ, Pimentel RC, Miana AA, Vieira AAB, Barroso AA.

Prinzmetal et al. variant angina is characterized by coronary vasomotor dysfunction leading to coronary spasm. Hyperventilation Test (HVT) with the aim of producing myocardial ischaemia was carried out in 30 patients who had angina and less than 30% atheromatosis on coronariography. HVT consisted of voluntary hyperpnea for 6 minutes with electrocardiographic readings every 2 minutes. At 5 minutes, MIBITc99m radiopharmaceutical was injected and SPECT images were subsequently obtained and compared to images obtained prior to the test. HVT-provoked hyperpnea was efficient to provoke respiratory alkalosis in all 30 patients as confirmed by arterial gasometry. Such alkalosis led to transient perfusional deficit indicating myocardial ischaemia on myocardial scintigraphy in 7 patients (23,33%). We conclude that HVT is able to lead to myocardial ischaemia with electrocardiography showing litlle sensibility and MIBI myocardial scintigraphy being of paramount importance.

1.2 - DOES ST DOWNSLOPE IN RECOVERY PHASE MEAN MYOCARDIAL ISCHEMIA? AN EVALUATION THROUGH MIBI-Tc-99m PERFUSION SCINTIGRAPHY.

Smanio P, Castro C, Martins D, LeBien D, Mostiack D, Valencia G,Thom AF.- Instituto Dante Pazzanese de Cardiologia , São Paulo, Brasil.

In exercise ECG, an ST downslope (ST infra) may occur only in the recovery phase. Its clinical meaning is not yet established. The present study aims to assess the possible correlation of that ECG finding with myocardial ischemia, taking MIBI-Tc-99m perfusion SPECT (MIBI) as the reference standart. The data of 61 patients, 38 men, mean age 58years, without previous infarct were reviewed. All had ST infra only during exercise recovery. From those, 16 (26%) showed stress/rest MIBI with at least one heart segment with a reversible uptake defect, compatible with ischemia. But it was noted that 40 /61 (65,5%) had hypertension. The results suggest that there is a minor correlation between recovery ST infra and ischemia but a significant incidence of hypertension can be found in this group of patients.

Salis FV, Coelho WM, Bellini A.J, Garzon S.A, Jacob J.L, Yokoyama H, Chuquer S, Loyo M, Iozzi THE, Vítola J, Paiva E. MN&D - Institute of Cardiovascular Diseases - S. J. Rio Preto, SP, Brazil.

With interest in evaluating the long term prognostic in patients with myocardial scintigraphy without isquemia after coronary angioplasty, we evaluated 183 patients, (201 vessels) among January to December 1993. All patients underwent myocardial perfusion image, using Sestamibi Tc-99m, medium period of 4,16 + 3,82 months after procedure. The Left Ventricle Ejection Fraction average was 76,6 + 7,9 performed by echocardiography .Of the analyzed patients, 151 didn't have isquemia in the scintigraphic data. Of these, only 9 (1,6%) needed new angioplasty, surgery or died in a medium period following 31,03 + 12,24 months. Of the 32 patients with isquemia in the scintigraphyc data, 23 (71,8%) needed new angioplasty, surgery or died in the same period of accompaniment (p <0,001). We concluded that those patients without isquemia in the scintigraphic myocardial perfusion after a medium period of four months, have an excellent long term prognostic in relation to need of new angioplasty or surgery and have low probability of cardiovascular death.

1.4 - EXERCISE AND DYPIRIDAMOLE MYOCARDIAL SCINTIGRAPHY IN THE EVALUATION OR REESTENOSIS POST STENT IMPLANT

Smanio P, Castro C, Martins D, LeBien D, Mostiack D, Valencia G, Thom AF. - Instituto Dante Pazzanese de Cardiologia, São Paulo.

This study aims to assess the value os post-exercise and post-dipyridamole MIBI-Tc-99m SPECT myocardial sicntigraphy to detect coronary artery reestenosis after stent implant. The results of 50 patients were analysed: 18 (36%) had reestenosis (Re) proven by cinecoronariography; 23 (52%) had maintained dilation results. Exercise stress scintigraphy (SC-1) was done in 34 patients and pharmacological stress scintigraphy (SC-2) in 16 patients. Those scintigraphies showing one or more reversible hypoperfused cardiac segments were called "positive". SC-1 was positive in 9/10 (93%) cases, SC-2 was positive in 8/8 (100%) with Re. From the 32 patients without Re, SC-1 was positive in 2/24 (10%) and SC-2 was positive in 1/8 (8,4%). Our results suggest that both stress and dipyridamole myocardial SPECT may be highly sensitive methods for the follow-up of patients with stent implant.

Vicino A, Nary F, Oliveira F, Montálveme J, Smanio P, Mastrocolla L, Thom AF.- Instituto Dante Pazzanese de Cardiologia, S. Paulo, Brasil.

The current study aims to evaluate the late evolution (after one year) of patients with discordant MIBI-Tc-99m perfusion SPECT(MIBI) and exercise stress test (EST) results. MIBI was considered positive when a reversible perfusion defect was present in at least one segment; EST was considered positive when ST downslope = > 1mm and/or chest pain was present. One hundred and twenty patients were reviewed. Twenty two had ischemia-negative EST and ischemia-positive MIBI (group I) and 98 had ischemia-positive EST and ischemia -negative MIBI (groupII). In group I 7/22 patients (31,8%) had late cardiovascular events. In group II only 10/98 (10,2%) had those events. The results confirm that in cases where EST and MIBI are discordant, MIBI shows the best correlation with coronary events in the late follow up

Sousa MCM, Vítola JV, Santos AO, Etchebehere ECSC, Ramos CD, Camargo EE. Division of Nuclear Medicine, Department of Radiology, Campinas State University (UNICAMP), Campinas, and Instituto Rio Preto de Medicina Nuclear, São José do Rio Preto, Brazil.

[F-18]FDG/PET myocardial images are the gold standard for the detection of myocardial viability. Coincidence imaging and high energy collimator imaging have made this method possible in this country. The purpose of this study was to describe our preliminary data with [F-18]FDG/SPECT. Five non-diabetic male patients (pts) (44-70 yrs) were studied for detection of viable myocardium post infarct using [F-18]FDG and a myocardial perfusion tracer. One pt was studied twice, in a total of 6 studies. Pts were in the fasting state for 6 hours prior to the study. In 5 studies the hyperinsulinemic euglycemic clamp was used; in 1 pt the study was performed after oral glucose overload. Pts received 370 MBq (10 mCi) of [F-18]FDG, 20 to 30 minutes after the clamp. A perfusion tracer (370 MBq) was injected immediately after beginning of the clamp or immediately after [F-18]FDG injection. In 4 studies [Tc-99m]sestamibi was used and in the remaining 2, [Tc-99m]furofosmin was used. Simultaneous [F-18]FDG and [Tc-99m]sestamibi SPECT were begun 30 minutes after [F-18]FDG injection, using a scintillation camera equipped with high energy collimators. Perfusion and metabolism images were analyzed together. Clamp images were of good quality; oral glucose overload images had a higher background activity, but were adequate for interpretation. Three studies were positive for viable myocardium and 3 were negative. [F-18]FDG/SPECT is possible in this country and offers adequate images for interpretation. Clamp studies were of a better quality in comparison to oral glucose overload studies.

Pozzo, L; Abe, R. - Serviço de radioisótopos - Instituto do Coração do HCFMUSP

A atenuação de raios g , devido à absorção e espalhamento dos mesmos pelos órgãos e tecidos do corpo humano, causa artefatos em imagens de SPECT. Estes artefatos se agravam no caso de exames de perfusão miocárdica devido à presença das mamas, diafragma, pulmões e arco costal - coeficientes de atenuação diferentes. O objetivo do presente trabalho é avaliar, de forma qualitativa, a correção de atenuação feita a partir de imagens de transmissão de fontes de Gd-153. Foi feita uma aquisição de um phantom cardíaco feminino, simulando uma distribuição de atividade homogênea no miocárdio (500m Ci) e com uma distribuição de fundo de concentração igual a 0,2m Ci/ml. A aquisição foi feita numa câmara de cintilação de dois detetores (Vertex-Plus - ADAC). Foram feitas 64 projeções, a partir de 315&ordm;, com tempo de exposição de 21s por projeção e zoom de 1,46. A reconstrução das imagens foi feita pelo método iterativo com 13 iterações, partindo da Retroprojeção Filtrada, com freqüência de corte de 0,5 (AutoSpect +1.08). A homogeneidade de todas as paredes do miocárdio apresentou melhora considerável, mostrando-se mais evidente na parede anterior.

Salis FV; Loyo Mário, Iozzi Adriana, Kassis M, Vítola J, Jacob J.L; Lorga A; Lorga Filho A; Garzon S; Belline A, Coelho W; Greque G, , Paiva E. MN&D - Institute of Cardiovascular Diseases - IMC - S. J. Rio Preto, SP, Brazil.

To evaluate possible changes in values of Left Ventricle Ejection Fraction (LVEF) depending on the acquisition protocol, we studied 62 patients with normal sinus rhythm, submitted to myocardial perfusion scintigraphic. Images were acquired in circular orbit 180 degrees (+ 45 RPO to &ndash; 45 LPO), 3 degrees steps, 45 minutes after injection of 1110 MBq for stress images (01 day protocol). Low energy collimation, matrix 64x64, 08 cycles frame and PVC acception of 20%, were used. The study was performed following threadmill exercise, the acquisition was coupled to the ECG and registered in sequence by PHASE and FRAME MODE protocols. There was continuous observation during studies to discard the occurrence of sustained arrhythmic periods. The images were processed and LVEF were calculaded. The mean LVEF for the FRAME protocol acquisition was 51,2%, while, the one obtained after PHASE acquisition was 55,3%. Based in these findings, we conclude that the FRAME MODE acquisition has a tendency to underestimate the LVEF in relation to the PHASE MODE, considering a 20% PVC threshold, even in those rhythmic patients, with short but non sustained variations of their heart rhythm.

Salis FV; Jacob J.L; Lorga A; Lorga Filho A; Garzon S; Belline A, Coelho W; Greque G, Loyo Mário, Iozzi Adriana, Vítola J, Paiva E; MN&D - IMC, Rio Preto - SP - Brazil.

Variations on left ventricle ejection fraction (LVEF) from rest to exercise may occur and on occasion may be related to some pathologic states, for example, induction of myocardial stunning following exercise. To evaluate if this is a clinically relevant issue for the routine evaluation of patients, we analysed 39 consecutive patients with known coronary artery disease undergoing exercise myocardial perfusion scintigraphy (1 day protocol). Images were acquired in circular orbit of 180 degrees (+ 45 RAO to - 45 LPO), with 3 degrees steps at 45 minutes following injection of 370 MBq of Sestamibi Tc-99m at rest and 1110 MBq at peak exercise. A matrix 64x64, 8 cycles per frame and PHASE MODE protocol (synchronized by the ECG) were parameters used for acquisition. The images were reconstructed, reoriented and processed, obtaining tomographic slices. A computer XPERT system (Elscint, Haifa-Israel), equipped with the Cedars G-SPECT program, was used for processing and for LVEF calculation.The mean LVEF obtained at rest following the rest injection was 54,2%, while the mean LVEF obtained at rest following the exercise injection was 55,1%. These findings support the hypothesis that there is no significant difference between LVEF values following rest or exercise injections for the routine evaluation of patients with coronary artery disease.

Almeida Filho, Paulo J; Lemos, Márcia R;Freitas, Alexandra C; Macedo, Gilberto; Almeida, Cristiana A - Laboratórios Cerpe, Recife-PE, Brazil.

We performed two-days 99mTc-Sestamibi SPECT Myocardial Perfusion studies, acquiring Gated - SPECT images at the post stress phase in 116 consecutive patients, 57&plusmn; 10 years (26 to 80). By using a commercial software (SPECT EF), we calculated the left ventricular ejection fraction (LVEF). Individuals with endocardial borders not well defined at the images were excluded. Data obtained was compared to Bidimentional Echocardiography (ECHO) and with Radioisotopic Ventriculography (RV).

Patients were divided in three groups: GI (n=86):normal Myocardial Perfusion and visual analyses of Gated SPECT images, compared to ECHO. GII (n=19): past history of myocardial infarction, compared to ECHO. GIII (n=11 ): past history of myocardial infarction and LVEF < 40% at the RV (ECHO was not performed at the same time).

Mean value of LVEF was 66&plusmn; 6,1% on GI, and the correlation with ECHO was R2=0,75 (a =0,05). On GII, we found 49&plusmn; 14% e R2=0,9 (a =0,05). On GIII, we obtained correlation with RV of R2=0,76 (a =0,05).

We conclude that LVEF obtained from Gated - SPECT technic, despite having the same limitations attributed to the Echocardiography, can add important and reliable information in a great number of patients, particularly for prognostic evaluation and, potentialy , on risk strattification post acute myocardial infarction.

C.A.Buchpiguel, J.L. Morais, C.A. Hossri, R. Pavanello, J.E. Souza, L.C.B. Sousa, A.D. Jatene. Hospital do Coração &ndash; Ass Sanatório Sírio-SP.

The authors report a 46 years-old physician who was reffered to us because of an atypical chest pain history.He had as risk factors for coronary artery disease (CAD) high serum colesterol levels and marked familial CAD history. Under the stress test he completed 4 stages in Bruce protocol, reaching the maximum predicted heart rate and blood pressure levels.Although he did not present any symptoms during the four stages, it was observed a 1.5 mm down slope of segment ST.In the 6 minute recovery period no abnormalites could be seen in the ECG. The myocardial perfusion scan without attenuation correction showed mild trasient defect in the inferior wall. However, after Gd-153 attenuation correction the defect described above disappeared. Three hours after finishing the functional imaging evaluation the patient started unstable angina and was immediately refered to cinecoronariography on which was seen a severe stenosis of the coronary artery disease.

C.A.Buchpiguel, V. Gimenez, H. Arakaki, R. Pavanello, E.R.Romano, L.C.B. Sousa, A.D. Jatene. Hospital do Coração &ndash; Ass Sanatório Sírio, São paulo-SP.

Our purpose was to determine a correlation between the left ventricle ejection fraction (LVEF) values obtained through myocardial perfusion scan and echocardiography. Thirty four patients were studies (20 male, mean age 53 + 11 yrs), with no previous history of any myocardiopathy or acute myocardial infarction, and who were reffered to us for coronary artery disease investigation. All patients underwent both studies within na interval period not superior to 3 months. Both methods showed normal values of LVEF, however, scintigraphy showed mean value of LVEF statistically lower than echocardiography (64,78% + 0,07 vs 69,72 + 0,06, respectively)(p=0,003). Moreover, the End Diastolic and Systolic Volumes were lower by scintigraphy in comparison to echocardiography. In conclusion, both methods showed LVEF values within the normal range, but scintigraphy provided lower values in comparison to echocardiography.

Padrão, EL; Barroso, A L; Netto, E; Moura, EMF; MOTA, GSC; Alcântara, GAA; Meira, ZMA -Mater dei &ndash; Departamento de Medicina Nuclear - MG

O aneurisma da ponta do coração é observado em aproximadamente 67% dos portadores de Miocardipatia Chagásica Crônica (MCHC). Habitualmente, a acinesia apical é de pequena dimensão e não afeta a função ventricular (FV). Entretanto, quando a dilatação aneurismática é extensa, pode comprometer a FV. Apresentamos o caso de uma paciente com MCHC que foi submetida a ressecção de grande aneurisma apical. MGA, 35 anos. sexo feminino, portadora de MCHC, evoluiu com queixas de dispnéia aos médios esforços, palpitações e pré-sincope. Foi iniciado tratamento com Inibidor de Enzima Conversora, Diurético e Amiodarona, A propedêutica realizada evidenciava: Teste Ergométrico (TE) - taquicardia ventricular esforço induzia, com repercussão hemodinâmica no terceiro estágio de Bruce: Ecocardiograma Transtorácico (EIT) - ventrículo esquerdo (VE) com grande dilatação aneurismática discinética na região apical, demais câmaras com dimensões e função preservada e Fração de Ejeção (FE) de 32%; Estudo Eletrofisiológico, - taquicardia ventricular monomórfica (TVM) não sustentada induzida, durante a estimulação programada e TVM sustentada com indução espontânea pós-isoproterenol; Cinecoronariografia e Ventriculografia Esquerda - coronárias um lesões ateromatosas e VE com grande aneurisma e discinesia na porção apical; Ventriculografia Radioisotópica (VRI) - FE de 36% (incluindo aneurisma) e de 46% (excluindo aneurisma). A aneurismectomia foi indicada. Após um ano de correção cirúrgica, a paciente encontra-se assintomática, em classe funcional 1 da NYHA e em uso de amiodarona. Os exames realizados mostraram: TE - a paciente atingiu a terceira carga de Bruce sem apresentar arritmias e/ou isquemia. Comportamento hemodinâmico fisiológico; ETT - VE com formato anatômico e dimensões normais, FE de 57%; VRI - boa função global de VE com FE de 74%. Nesse caso, a realização de aneurismectomia proporcionou melhora da FV vistos ao ETT e VRI.

Coelho BP; Soares Jr. J; Giorgi MCP; Izaki M; Meneghetti JC - Nuclear Medicine Department - Heart Institute - São Paulo University School of Medicine (Brazil)

We report a case of a 67-year-old male patient, diabetic, who had had rest chest pain events during the last ten days, referred for dipyridamole/rest SESTAMIBI-Tc99m myocardial perfusion scintigraphy (1st study). The rest images showed inferolateral wall defect. During dipyridamole infusion the patient developed typical chest pain, which required aminophylline infusion. The baseline EKG showed atrial fibrillation and ST depression (V2-V5). During the chest pain there was intensification of the ST depression. After the acquisition of stress images, which showed the same pattern observed at the rest study, the patient also complained of chest pain and was sent to the emergency unit where inferolaterodorsal acute myocardium infarction was detected.

At the emergency unit the patient was promptly submitted to thrombolysis with reperfusion. The coronariography showed 95% lesion in the 3rd left marginal and PTCA was successfully performed. The SESTAMIBI-Tc99m scintigraphy at rest and exercise (2nd study), performed 4 months later, showed normal myocardial perfusion.

Afterwards the patient reported that he had had chest pain during the rest injection of the first study. There were no significant changes in myocardial perfusion with dipyridamole compared to rest, probably because the local flow and/or metabolism were already very impaired at the baseline condition itself (tissular ischemia). Therefore, the persistent defect observed in the 1st study did not mean myocardial fibrosis.

1.15 - THYMIC UPTAKE DEMONSTRATED BY GALLIUM-67 SCINTIGRAPHY IN A HEART TRANSPLANTED PATIENT: CASA REPORT.

Neves, AC; Hyai, A; Carvalho,G; Weigert, C; Izaki, M; Giorgi,MC; Soares Jr,J; Meneghetti, JC - Nuclear Medicine Department of the Heart Institute. University of São Paulo - Brazil