Radionuclide gated blood pool and Tc-99m RP-30 imaging in latissimus dorsi dynamic cardiomyoplasty of the right ventricle in a canine model

Latissimus dorsi (LD) cardiomyoplasty (grafting a full-thickness LD flap into the right ventricle) to replace excised or damaged myocardium was performed in dogs. Electrocardiographically gated Tc-99m gated blood pool imaging was performed prior to and after 6 weeks of LD stimulator training, with the stimulator on (7.5 V; frequency, 30 Hz; duration, 185 msec) and off. The right ventricular ejection fraction was 65% (stimulator off) and rose to 81% (stimulator on). These results correlated well with right ventricular pressure, dp/dt, and the percentage of LD muscle shortening. Gated Tc-99m RP-30 images showed increased uptake in the LD flap region. The utility of Tc-99m RP-30 as an indicator of LD flap integrity is promising