RESUMO
BACKGROUND AND OBJECTIVE: The usefulness of preoperative angiographic evaluation of the internal mammary artery (IMA) is controversial. The aim of this study is to evaluate the problem by a basic cost-benefit analysis. METHODS: One hundred and twenty-one patients whose coronary findings (left main disease and/or severe stenosis of the left anterior descending artery) made use of the IMA as a bypass graft a consideration were studied. The IMA was cannulated by the same right Judkins catheter used in the coronarography; the specific catheter was only used if the cannulation was not successful with the right Judkins. We measured the time it took for a good angiography of the IMA to be obtained; the anatomy and the size for each IMA were studied and compared with the size of the left anterior descending artery. RESULTS: An optimal angiographic picture of the IMA was obtained in 119 cases (98.3%); a specific catheter was used only in 3 patients. The mean of the time employed was 170 seconds (8-900 s) and no complications were related to IMA cannulations. Angiography findings relevant to any planned surgery were demonstrated in 15 patients (12%): large proximal branches (10); occlusion stenosis or a caliber insufficient for IMA (3); and occlusion or proximal subclavian stenosis (2). CONCLUSIONS: We have observed that the relation between the cost and the obtained information is adequate to warrant its performance, because angiographic findings relevant to planned surgery can be very important, even though they are fairly infrequent. Moreover, these findings can be achieved rapidly without additional cost.
Assuntos
Doença das Coronárias/cirurgia , Anastomose de Artéria Torácica Interna-Coronária , Artéria Torácica Interna/diagnóstico por imagem , Angiografia Coronária , Doença das Coronárias/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
To evaluate the usefulness of treadmill exercise test in the diagnosis of coronary restenosis, we have chosen a sequential and probabilistic analysis. The rate of coronary restenosis found in the sample (n = 213) was of 30%. This initial probability of having restenosis was radically changed by the recurrence of typical angina: 77% in patients with this symptom, 17% in those without (p < 0.001). In contrast, the qualitative result of the exercise test was unable to change significantly the probabilities established after anamnesis. This was due to a lower specificity for exercise test (76%) than for angina (93%), the sensibility being the same (56%) for both. Employment of a discriminant value that integrates different ergometric variables did not enhanced sensibility, but allowed the identification of a good number of false positive results and therefore palliated the negative impact of faulty specificity. Being applied to a "discordant group" (no angina/positive exercise test, n = 34) was able to achieve a significant change in probability: from 15% to 50% or 4% (p < 0.01), according to the discriminant being lesser or greater than a preestablished value. In conclusion, prevalence of the event and evaluation of symptomatology are both important to estimate the probability of suffering coronary restenosis. On the contrary, exercise test, in the absence of a weighty method, adds more confusion than clarity to the analysis of the problem. Our results can be used to improve the follow-up of patients who have been successfully dilated by angioplasty.