Three-dimensional electromechanical mapping: Imaging in the operating roomof the future

Background. Three-dimensional electromechanical mapping has previously been shown to be a clinically important tool for cardiac imaging and interventi on. We hypothesized that this technology may be beneficial as an intraopera tive modality for assessing cardiac hemodynamics and viability during cardi ac surgery. We report here the use of this technology as an imaging modalit y for intraoperative cardiac surgery. Methods. The tip of a locatable catheter connected to an endocardial mappin g and navigating system is accurately localized while simultaneously record ing local electrical and mechanical functions. Thus the three-dimensional g eometry of the beating cardiac chamber is reconstructed in real time. The s ystem was tested on 6 goats that underwent acute dynamic cardiomyoplasty an d on 5 dogs that underwent left anterior descending (LAD) coronary artery l igation. Results. The electromechanical mapping system provided an accurate three-di mensional reconstruction of the beating left ventricle during cardiomyoplas ty. After the wrapping procedure, significant end-diastolic area reduction was noted in the base and mid parts of the heart (948 +/- 194 mm(2) VS 1245 +/- 33 mm(2), p = 0.021; and 779 +/- 200 mm(2) vs 1011 +/- 80 mm(2), p = 0 .016). The area of the cross-section of the apex did not change during the operation. Acute infarcted tissue was characterized 3 days after LAD ligati on by concomitant deterioration in both electrical and mechanical function. Conclusions. By providing both a clear view of the anatomical changes that occur during cardiac surgery, and an accurate assessment of tissue viabilit y, electroanatomic mapping may serve as an important adjunct tool for imagi ng and analysis of the heart during cardiac surgery (C) 2001 by The Society of Thoracic Surgeons.