Remodelamento da artéria torácica interna direita: novo método de análise pela área coronariana revascularizada / Remodeling of the right internal thoracic artery: new method of analysis using the coronary area grafted

OBJETIVO: Avaliar os fatores angiográficos no remodelamento da artéria torácica interna (ATI) direita por novo método quantitativo com a área coronariana revascularizada. MÉTODO: No período entre janeiro de 1992 e 2002, 452 pacientes foram submetidos à revascularização do miocárdio (RM) com ATI bilateral. Desta amostra, 32 pacientes com ponte de ATI direita "in situ" pelo seio transverso foram reestudados por meio de cineangiocoronariografia (CATE). Os filmes foram analisados na plataforma CASS II®. Quanto aos critérios angiográficos, foram medidos os diâmetros proximal e distal das ATIs, área coronariana da artéria revascularizada, pontuação pela escala de fluxo de TIMI, diâmetro de estenose proximal, dominância de fluxo e presença de ramos acessórios patentes. RESULTADOS: O período médio de acompanhamento foi de 42 meses, variando de 6 a 204 meses. As medidas da ATID proximal foram de 2,639 mm ± 0,09 e distal de 2,159 mm ± 0,1 (p<0,001). A variável área coronariana correspondente à artéria marginal apresentou um coeficiente de ß de 0,424 (p<0,001) e o diâmetro de estenose da marginal um coeficiente de ß de 0,55 (p<0,0001) ajustados por peso, altura, intervalo cirurgia/CATE, escala de fluxo de TIMI "flow" , classificação de angina e Hipertensão Arterial Sistêmica (HAS), com R² ajustado de 0,696 (p<0,0001). CONCLUSÃO: Na amostra estudada, por critérios angiográficos quantitativos, a área coronariana revascularizada e o diâmetro de estenose proximal apresentaram-se como fatores independentes no remodelamento da ATID, no pós-operatório de RM.

OBJECTIVE: To analyze angiographic factors related to remodeling of the right internal thoracic artery (RITA) using a new quantitative technique of the target coronary grafting area. METHOD: In the period from January 1992 to 2002, 452 consecutive patients were submitted to coronary artery bypass grafting (CABG) with RITA "in situ" through the transverse sinus. In this sample, 32 patients were submitted to at least one postoperative coronariography study after receiving RITA grafts. The studies were analyzed by the CASS II® software. The angiographic criteria assessed were the proximal and distal diameters of the RITA, coronary area irrigated by the target vessel, TIMI flow score, quantitative coronary angiography(QCA), dominant flow grade and the existence of patent lateral branches of the RITA. RESULTS: The mean follow-up period was 42 months, ranging from 6 to 204 months. The mean proximal diameter of the RITA was of 2.639 mm ± 0.09 and the distal diameter was 2.159 mm ± 0.1 (p < 0.001). The coronary irrigated by the target marginal branch presented a ß coefficient of 0.424 (p=0.001) and diameter of the stenosis (QCA) of the marginal branch gave a ß coefficient of 0.55 (p=0.001) adjusted by weight, height, time surgery/study, TIMI flow score, angina functional class and systemic hypertension. Multiple regression modeling demonstrated an adjusted R2 of 0.696 (p<0.0001). CONCLUSION: This study, using angiographic evaluation, demonstrated that the coronary area and proximal diameter (QCA) of the marginal branch stenosis were independent factors in RITA remodeling in the postoperative of CABG.

Detection of construction errors in ex vivo coronary artery anastomoses by 13-MHz epicardial ultrasonography.

OBJECTIVE: Intraoperative detection of suboptimal coronary anastomoses allows revision before chest closure. We evaluated an epicardial 13-MHz ultrasound minitransducer as a means to detect three different coronary anastomosis construction errors. METHODS: In total, 120 internal thoracic artery-to-coronary artery anastomoses were constructed correctly (n = 60) or incorrectly (n = 60) with one technical error: suture crossover, purse-string or deep toe stitch (n = 20 each). Anastomoses were performed on ex vivo pressure-perfused porcine (96 anastomoses) and human hearts (24 anastomoses). Two blinded observers scanned and scored the anastomoses with epicardial ultrasonography. In 24 human and 24 porcine anastomoses, angiograms were made of 24 correct and 24 incorrect anastomoses and scored by two other blinded observers. Angioscopy and cast injection served as a reference. RESULTS: Overall, 119 of 120 anastomoses were accurately scored as correct or incorrect within a median of 67 seconds (8-381 seconds) by both observers (sensitivity 0.98, specificity 1.00, kappa 1.00 (1.00, 1.00, and 1.00 in angiography subset, respectively). One deep toe stitch that induced outflow corner stenosis was spotted by both observers but regarded as insignificant and thus inaccurately scored as correct. In 5 anastomoses, unintended irregularities were detected. By angiography, anastomoses were accurately scored with a sensitivity of 0.75 and a specificity of 0.81 ( P < .001 vs ultrasonography) and kappa of 0.54. Angioscopy and cast confirmed ultrasonographic findings and did not reveal irregularities other than detected by ultrasonography. CONCLUSION: Ex vivo epicardial 13-MHz ultrasonography allowed rapid and accurate evaluation of coronary anastomoses and detected technical construction errors with higher sensitivity and specificity than angiography.