Title: Myocardial perfusion during exercise in patients after bypass grafting using internal mammary artery
- Krzysztof Chiżyński, Jacek Kuśmierek, Alicja Iwaszkiewicz-Zasłonka, Ryszard Jaszewski, Janusz Zasłonka
- Original articles
- Polish Journal of Cardiology
- Start page:
- Final page:
- bypass, internal mammary artery, perfusion scintigraphy
Introduction: Internal mammary artery (IMA) is now used as a conduit of choice for the grafting of the left an-terior descending coronary artery (LAD).
Aim: The aim of the study was to evaluate resting and exercise myocardial perfusion in patients after IMA bypass and to define the relationship between IMA blood outflow (IMA flow to "atmosphere") and the results of coronary operation.
Material and methods: IMA blood outflow was measured during bypass procedurę in 68 patients. Three mon-ths after the bypass procedurę 201Thallium myocardial perfusion scintigraphy was performed in all patients. Perfusion was expressed as the tracer activity graded on a scalę ranging from 0 (absent) to 2 (normal) with grades increasing by 0.5.
Results: IMAflowto "atmosphere" below 100 ml/min was observed in 30% patients. In the 70% of study patients IMAflow "atmosphere" was morę than 100 ml/min. Good surgical results defined as normal perfusion during exercise and in the resting images (group A) or very small exercise induced perfusion defects and normal perfusion at rest (group B) were observed in 57 patients (84%). 201Thallium myocardial perfusion scintigrams were analyzed separately in the patients with IMAflow "atmosphere" below 100 ml/min and morę than 100 ml/min. Good bypass results (group A and B scintigrams) were observed in 98% patients with IMA flow to "atmosphere" morę than 100 ml/min but only in 50%patients with IMA flow to "atmosphere" below 100 ml/min (p<0.001). Unsatisfactory surgical results were found in 50% patients with IMA flow below 100 ml/min, and only in 2% patients with IMAflow morę than 100 ml/min (p<0.001). Conclusions: IMA flow to "atmosphere" measured intraoperatively has an important predictive value for the out-comeof coronary arterygrafting. The useof IMA only in the cases where the minimalflowto "atmosphere" is 100 ml/min might improve the results of coronary grafting.