Evaluation of viability in ischaemic cardiomiopathy using NOGA: comparative accuracy of rest-redistribution thallium-201 and echo stress dobutamine after successful revascularization

Aim: NOGA endocardial mapping is a new technique that detects myocardial viability by recording the endocardial electrical signals. Aim of this study were: 1-to prospectively evaluate accuracy of NOGA in prediction of recovery of left ventricular function after revascularization in patients with ischaemic cardiomyopathy and multi-vessel disease 2-to compare its accuracy to thallium-201 rest-redistribution scintigraphy (TL) and echo-stress dobutamine (DSE). Material and methods: Sixteen male patients, mean age 63 y (range 47-73 y); mean LVEF 28%, were consecutively enrolled in our study. Inclusion criteria were: severe depression of LVEF (< 35%) dilated left ventricle (end diastolic volume ≥ 100 ml/m2), multi-vessel coronary artery disease and anatomical feasibility of revascularization with bypass graft or angioplasty. Exclusion criteria were: acute or recent myocardial infarction, aortic valve disease, left ventricular thrombus. Patients underwent coronary and ventricular angiography as well as NOGA mapping, DSE and rest-redistribution TL. The patients had complete revascularization. The gold standard was the recovery of wall motion 6 months after revascularization. The NOGA threshold of viability was considered 6mV. Results: The mean voltage at NOGA map was 7.6mV in the segments that improved, 4.8mV in the ones that didn't improve (p<0.01). Patients with >6 segments with voltage < 6mV didn't show any improvement in LVEF. NOGA had the best sensitivity (75%) and negative predictive value (90%). DSE had the best specificity (91%) and negative predictive value (87%). Detailed results are presented. Conclusions: NOGA segmental voltage < 6mV identifies areas that will not recover. Patients with more than six of these areas, will not likely demonstrate a LVEF improvement after revascularization. Our data are do not demonstrate NOGA can be used instead of other methods currently used to assess myocardial viability