Abstract Background Coronary flow and myocardial contractile performance assessed by strain magnitude increase during a dobutamine stress echocardiogram (DSE). Normal coronary flow reserve (CFR) can be attained upon completion of a DSE at age-predicted maximum heart rate (HR) (HRmax = 220 - age)] or submaximal HR [(0.85) HRmax] or before completion (early CFR). Objective To ascertain the association between delta strain and HR in patients with early normal CFR. Methods This prospective study included patients whose normal CFR was obtained before the DSE was completed. Percentage of resting HR (%HRrest) = [(HRrest ÷ HRmax) 100]% and %HR CFR = [(HR at the time of CFR attainment) ÷ (HRmax) 100]% were recorded. Strain was assessed in the left ventricular region of interest, and delta strain was calculated as the difference between the measures obtained at HRrest and after the DSE was completed. Strain agreement analysis for HRrest, %HRrest, and %HR CFR was performed using the kappa coefficient. The Shapiro-Wilk test was used to assess data normality, and the Mann-Whitney test was used to compare the groups. A p-value < 0.05 was considered statistically significant. Results Strain measured -23.3% ± 4.3% at baseline and -31.1% ± 4.9% during the DSE. In delta strain > 8 absolute points, the ROC curves showed an area under the curve of 0.874 ± 0.07 for %HRrest (p = 0.001) and an area under the curve of 0.862 ± 0.07 for %HR CFR (p = 0.001). In delta strain > 8 points, %HRrest ≤ 42.6% of HRmax and %HR CFR ≤ 62.5% of HRmax showed an accuracy of 82.9% and 79.8%, respectively. Conclusion In this study, lower HRrest and HR at the time of CFR attainment had a good association with better myocardial contractile performance, according to the change in strain magnitude.

Resumo Fundamento: A reserva de velocidade de fluxo coronariano (RVFC) adequada (≥ 2) obtida na artéria descendente anterior (ADA) através do ecocardiograma transtorácico associa-se a bom prognóstico, mas não há estudo correlacionando-a com a frequência cardíaca (FC) alvo (submáxima). Objetivo: Avaliar o valor prognóstico da RVFC obtida na ADA de pacientes com fração de ejeção do ventrículo esquerdo (FEVE) preservada (>50%) e ecocardiograma sob estresse com dobutamina (EED) concluído, considerando a FC alvo submáxima. Métodos: studo prospectivo de pacientes com FEVE preservada e RVFC obtida na ADA durante EED concluído. No Grupo I (GI=31), a RVFC adequada foi obtida antes de se atingir a FC alvo, e no Grupo II (G II=28), após. O Grupo III (G III=24) atingiu a FC alvo, mas a RVFC foi inadequada. Foram considerados eventos: óbito, insuficiência coronariana aguda, intervenção coronariana, coronariografia sem intervenção subsequente e internamento hospitalar. Resultados: Em 28 ± 4 meses, ocorreram 18 (21,6%) eventos, sendo 6% (2/31) no GI, 18% (5/28) no GII e 46% (11/24) no GIII. Foram 4 (4,8%) óbitos, 6 (7,2%) intervenções coronarianas e 8 (9,6%) coronariografias sem intervenção subsequente. Na sobrevida livre de eventos pela análise de regressão, GIII apresentou mais eventos do que GI (p < 0,001) ou GII (p < 0,045), não havendo diferença entre GI e GII (p = 0,160). Após o ajustamento, foi mantida a diferença apenas entre GIII e GI (p = 0,012). Conclusão: Em pacientes com FEVE preservada e EED concluído, a RVFC adequada obtida antes da FC alvo associou-se ao melhor prognóstico.

Abstract Background: Normal coronary flow velocity reserve (CFVR) (≥ 2) obtained in the left anterior descending coronary artery (LAD) from transthoracic echocardiography is associated with a good prognosis, but there is no study correlating CFVR with submaximal target heart rate (HR). Objective: To evaluate the prognostic value of CFVR obtained in the LAD of patients with preserved (>50%) left ventricular ejection fraction (LVEF) who completed a dobutamine stress echocardiography (DSE), considering target HR. Methods: Prospective study of patients with preserved LVEF and CFVR obtained in the LAD who completed DSE. In Group I (GI = 31), normal CFVR was obtained before achieving target HR, and, in Group II (GII = 28), after that. Group III (G III=24) reached target HR, but CFVR was abnormal. Death, acute coronary insufficiency, coronary intervention, coronary angiography without further intervention, and hospitalization were considered events. Results: In 28 ± 4 months, there were 18 (21.6%) events: 6% (2/31) in GI, 18% (5/28) in GII, and 46% (11/24) in GIII. There were 4 (4.8%) deaths, 6 (7.2%) coronary interventions and 8 (9.6%) coronary angiographies without further intervention. In event-free survival by regression analysis, GIII had more events than GI (p < 0.001) and GII (p < 0.045), with no difference between GI and GII (p = 0.160). After adjustment, the only difference was between GIII and GI (p = 0.012). Conclusion: In patients with preserved LVEF and who completed their DSE, normal CFVR obtained before achieving target HR was associated with better prognosis.

FUNDAMENTO: A artéria torácica interna enxertada (ATIE) patente usualmente tem fração diastólica (FD)> 50% do fluxo. O estado funcional pode ser avaliado pelo índice de reserva coronariano (IRC). OBJETIVO: Avaliar, pela ecocardiografia e pelo Doppler em nível supraclavicular, a patência e o estado funcional da ATIE. MÉTODOS: Foram coletados prospectivamente e analisados os dados de 66 pacientes submetidos a ecocardiograma sob estresse com dobutamina (EED). O grupo I (GI) ocorreu com 49 ATIE sem estenose. No grupo II (GII) (10 ATIE) havia estenose significativa (> 50% e <100%). E no grupo III (GIII) (7 ATIE) a oclusão era de 100%. Foram avaliados diâmetros e espectros do Doppler das ATIE no repouso e EED. RESULTADOS: Considerando patência uma FD>50%, ocorreu em 49 ATIE (GI=40, GII=8 e GIII=1) no repouso e em 61 ATIE (GI=49, GII=10 e GIII=2) durante EED. Sensibilidade, especificidade, valor preditivo positivo (VPP), valor preditivo negativo (VPN) e acurácia foram, respectivamente, em repouso, 81%, 86% ,98%, 35 % e 82%; e no EED, 100%, 71%, 97%, 100% e 97%. As ATIE com FD>50% em repouso estavam patentes e as com FD<50% no EED tinham oclusão total. Considerando para bom estado funcional um IRC>1,8, isso ocorreu em 42 ATIE (39 do GI, 2 do GII e 1 GIII), verificando-se sensibilidade = 79%; especificidade = 85,7%; VPP = 94%; VPN = 59%; e acurácia = 80,9%. O IRC no GI foi maior (p=0,02) que em GII e GIII. CONCLUSÃO: Em nosso estudo, a avaliação não-invasiva da ATIE foi efetiva para verificar patência e estado funcional.

BACKGROUND: The patent internal thoracic artery graft (ITAG) usually has a diastolic fraction (DF) > 50% of the flow. The functional assessment can be evaluated by the coronary reserve index (CRI). OBJECTIVE: The objective was to evaluate the patency and functional status of the ITAG through echocardiography and Doppler. METHODS: Data from sixty-six patients who underwent dobutamine-stress echocardiography (DSE) were prospectively collected and analyzed. Group I (GI) had 49 ITAG without stenosis, Group II (GII), 10 ITAG with significant stenosis (> 50% and <100%) and Group III (GIII) had 7 ITAG with total occlusion. Diameters and Doppler spectrums from the ITAG at rest and during DSE were evaluated. RESULTS: Considering patency a DF >50%, it was observed in 49 ITAG (GI= 40, GII= 8 and GIII= 1) at rest and in 61 ITAG (GI=49, GII=10 and GIII=2) during DSE. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy were respectively, 81%, 86%, 98%, 35% and 82%, and 100%, at rest and 71%, 97%, 100% and 97% in the DSE. The ITAG with DF>50% at rest were patent and the ones with DF<50% in the DSE presented total occlusion. Considering a CRI>1.8 for a good functional status, it was observed in 42 ITAG (39 from GI, 2 from GII and 1 from GIII), determining sensitivity=79%, specificity=85.7%, PPV=94%, NPV=59% and accuracy= 80.9%. The CRI in GI was higher (p= 0.02) than in GII or GIII. CONCLUSION: In our study, the non-invasive assessment of the ITAG was effective to verify the patency and the functional status.

OBJETIVO: Verificar a exeqüibilidade e segurança do ecocardiograma sob estresse com dobutamina e atropina (EED) em octogenários. MÉTODOS: Avaliaram-se 5.467 EED, distribuídos entre grupo dos octogenários (GI=203) e grupo controle (GII=5.264). A idade média no GI=83±3 (80-95) e no GII=59±11 (17-79) anos. Os parâmetros resultantes do EED, coletados prospectivamente, foram comparados e analisados. RESULTADOS: O percentual de pacientes que atingiram freqüência cardíaca máxima foi em GI=63,5% e GII=41% (GI vs. GII; p<0,001), e o GI necessitou de menos atropina (GI=47% vs. GII=78%; p<0,001). A ocorrência de dor não foi significativamente diferente (GI=13% vs. GII=15,6%; p=0,429), nem o percentual de EED positivo para isquemia miocárdica (GI=20,7% vs. GII=16,9%; p=0,296), mas a concomitância entre EED positivo e ausência de dor (GI=17% vs. GII=11%; p=0,029) foi maior no grupo I. A ocorrência de extra-sistolia (GI=47,8% vs GII=27,6%; p<0,001) e taquiarritmia supraventricular (GI=5,9% vs. GII=1,9%; p=0,001) foi maior no grupo I. Das 11 taquiarritmias supraventriculares do grupo I, 9 reverteram espontaneamente. Não houve óbito, infarto ou prevalência de taquicardia ventricular. Só ocorreu fibrilação ventricular (2 casos; 0,03%) no GII. CONCLUSÃO: Apesar do menor uso de atropina para concluir o EED, os octogenários atingiram mais a freqüência cardíaca máxima. Houve uma maior correlação entre EED positivo para isquemia miocárdica e a ausência de dor. Apresentaram mais distúrbios do ritmo, todavia a resolução, em geral, foi espontânea. Em nosso estudo, o EED mostrou ser um método exeqüível e seguro para os octogenários.

OBJECTIVE: To assess the feasibility and safety of dobutamine-atropine stress echocardiography (DASE) in octogenarians. METHODS: We evaluated 5,467 DASE which were distributed in two groups: group I (GI) with 203 DASE performed in octogenarians, and group II (GII), the control group, with 5,264 DASE. The mean age of GI and GII was 83±3 (80-95) and 59±11 (17-79) years, respectively. DASE parameters that were prospectively collected, were compared and analyzed. RESULTS: The percentage of patients that achieved maximum heart rate was 63.5% in GI and 41% in GII (p<0.001), and GI patients required less atropine compared to GII (GI=47%, GII=78%, p<0.001).The presence of chest pain (GI=13%, GII=15.6%, p=0.429) and DASE positive for myocardial ischemia (GI=20.7%, GII=16.9%, p=0.296) were not statistically different between the two groups. However, concomitant positive DASE and absence of chest pain (GI=17%, GII=11%, p=0.029) was higher in GI. The incidence of premature beats in GI was higher than in GII (GI=47.8%, GII=27.6%, p<0.001), and there were more supraventricular tachyarrhythmias (ST) in GI than in GII (GI=5.9%, GII=1.9%, p=0.001). Out of 11 ST that happened in GI, 9 reverted spontaneously. There weren't either deaths or acute myocardial infarction. Ventricular fibrillation only happened in GII (2 cases, 0.03%). CONCLUSION: In the present study, octogenarians achieved maximum heart rate more frequently despite the lesser amount of atropine that they required for DASE completion. Moreover, in this elderly population, there was a higher correlation between positive DASE and absence of chest pain. Although octogenarians did present more heart rhythm disturbs, they usually resolved spontaneously. In our study, DASE proved to be feasible and safe in octogenarians.

INTRODUÇÃO: A circulação extracorpórea (CEC) e o manuseio da aorta ascendente (MAA) estão associados a alta incidência de acidente vascular cerebral (AVC) na cirurgia de revascularização do miocárdio (RM) em pacientes idosos. Esta complicação deve-se, sobretudo, ao MAA, por ocasião do pinçamento e despinçamento, quer para isolamento do coração do circuito de CEC, quer para realização das anastomoses dos enxertos na aorta ascendente. OBJETIVOS: Verificar mortalidades imediata e a médio prazo e a ocorrência de AVC no pós-operatório imediato (POI) em pacientes acima de 75 anos submetidos a cirurgia de revascularização do sistema coronariano esquerdo (SCE), sem CEC e sem MAA. MÉTODO: De janeiro de 2000 a abril de 2002, 40 pacientes acima de 75 anos (média 79,1 anos) foram submetidos a cirurgia de revascularização do SCE, com enxerto de artéria torácica interna esquerda (ATIE) para a artéria descendente anterior (DA), e enxerto(s) de veia safena magna oriundo(s) da ATIE para outro(s) ramo(s) da coronária esquerda (enxerto composto), sem CEC e sem MAA. Houve predominância do sexo masculino (67,5%). Foram realizados 89 enxertos (média 2,22 pontes por paciente), sendo 40 (44,94%) de ATIE e 49 (55,06%) de veia safena. A ocorrência de AVC foi avaliada por exames clínico e neurológico. RESULTADOS: Não foi observada ocorrência de AVC no grupo estudado. Não houve óbitos no POI. CONCLUSÃO: A cirurgia de revascularização do SCE em pacientes acima de 75 anos sem CEC e sem MAA pode ser realizada sistematicamente de modo a evitar a ocorrência de AVC, com baixa mortalidade.

INTRODUCTION: Cardiopulmonary bypass (CPB) and Ascending Aorta manipulation (AAM) are associated with a high incidence of stroke in coronary surgery in patients older than 75 years. This complication is due, mostly, to the handling of the aorta by the time of the cross-clamping, either for heart isolation from CPB, or to perform saphenous vein graft anastomosis to the ascending Aorta. OBJECTIVES: To observe immediate and mid-term mortalities and occurrence of stroke in the immediate post-operative period in patients older than 75 years who underwent surgical revascularization of the Left Coronary Artery System (LCAS) without CPB and without AAM. METHOD: Between January 2000 and April 2002, 40 patients, with ages ranging from 75 to 89 years (average 79.1), underwent surgical revascularization of the LCAS, with Left internal mammary artery (LIMA) graft to the Left Anterior Descending artery (LAD), and with Saphenous Vein Graft (SVG) originated from LIMA to one or more left coronary artery branches (composite graft), without CPB and without AAM. Male gender was predominant (67.5%). Eighty-nine arterial grafts were performed, with average of 2.22 per patient, of which 40 (44.94%) of LIMA and 49 (55.06%) of saphenous vein. The occurrence of stroke was evaluated by neurological and clinical exams. RESULT: It was not observed stroke or deaths in the immediate post-operative period. CONCLUSION: Surgical revascularization of the LCAS in patients older than 75 years without CPB and without AAM can be performed systematically in order to avoid occurrence of stroke, and so, reducing the mortality of the procedure.