Identification of functioning viable and non-viable myocardium using GBP-NTG and angiography

ABSTRACT

The study included 41 patients with coronary artery disease evaluated using Tl-201 re-injection with NTG for assessment of myocardial viability. Correlation of viable segments [107] and non-viable segments [91] by angiography and radionuclide ventriculography [resting and following 10 mg sublingual NTG]. The addition of NTG lead to significant changes in ejection fraction [EF], peak emptying rate [PER] and peak filling rates [PFR]. Similar normal segmental wall motion in 64% and 65% of viable segments was observed in both GBP and angiography as well as 46% and 47% of non-viable segments using the same techniques. GBP had a better detection for hypokinetic segments in 36% and 42% in viable and non-viable segments versus 24% and 34% in angiography in the same groups respectively. Also, GBP had higher detection rate of dyskinesia in 12% in non-viable segments as compared to 2% in angiography. Viability index > 50% had significant correlation with mean degree of coronary stenosis [p < 0.001], whereas it had no significant correlation with haemodynamic variables as EF, PER and PFR. Radionuclide ventriculography [GBP] with NTG is a better technique in assessment of wall motion changes among viable and non-viable segments, whereas the mean coronary stenosis is the main factor correlated with viability index