Technetium-99m-sestamibi imaging with nitrate infusion to detect viable hibernating myocardium and predict postrevascularization recovery.

UNLABELLED

We tested the relationship of nitrate-induced changes in 99mTc-sestamibi perfusion tomography and first-pass radionuclide angiocardiography (FPRNA) with postrevascularization functional recovery of asynergic territories.

METHODS

Twenty-eight patients, all with prior infarction and left ventricular dysfunction, underwent two 99mTc-sestamibi rest studies: one under baseline conditions and the other with nitrate infusion. The baseline study was repeated after revascularization. Changes in global and regional perfusion and ventricular function were evaluated by perfusion tomography and FPRNA. Hibermating myocardium was identified by functional recovery in postrevascularization FPRNA.

RESULTS

Eleven patients and 31 segments in 19 coronary territories had functional recovery. Nitrate-induced FPRNA changes showed poor agreement with postrevascularization modifications: kappa = 0.24, ns, for the global and kappa = 0.32, p < 0.01 for regional function. The agreement between nitrate-induced and postrevascularization perfusion changes was good both considering the patients (k = 0.57, p < 0.01) and the abnormal coronary territories (k = 0.63, p < 0.0005). The agreement of nitrate-induced perfusion changes with postrevascularization functional outcome was excellent on a patient (k = 1, p < 0.0005), and coronary territory basis (k = 0.82, p < 0.0005). Conversely, the agreement between nitrate and postrevascularization FPRNA was poor: k = 0.18, ns.

CONCLUSION

These data suggest that the nitrate-induced changes in 99mTc-sestamibi perfusion imaging are useful to detect hibernating myocardium which recovers its function after revascularization.