NORMAL VALUES AND REPRODUCIBILITY OF LEFT-VENTRICULAR FILLING PARAMETERS BY RADIONUCLIDE ANGIOGRAPHY

Background. In physiologic situations age, heart rate (HR) and left ve ntricular ejection fraction (EF) may influence left ventricular fillin g rate. In this study, we determined normal values for radionuclide an giography (RNA) derived diastolic filling parameters, the correlations with age, HR and EF and their reproducibility. Methods. The study was performed in 20 patients, 40-76 years old (mean 57), with normal find ings at coronary angiography and left ventriculography. The first RNA was performed at rest (RNA1). Then, five minutes bicycle ergometry was performed and the patients were allowed five minutes rest before RNA was repeated (RNA2). From the left ventricular time activity curve we determined peak filling rate (PFR), time to peak filling rate (TPFR) a nd atrial contribution (AC) to ventricular filling. Results. Values fo r PFR1 were 2.2 +/- 0.6 EDV/sec (PFR2 2.4 +/- 0.7 EDV/sec, r = 0.82), for TPFR1 198 +/- 22 msec (TPFR2 203 +/- 24 msec, r = 0.45) and for AC l 31 +/- 11% (AC2 31 +/- 10%, r = 0.72). The correlations of PFR and T PFR with age were statistically significant (respectively r = - 0.68 a nd r = 0.48, P < 0.05). PFR was also influenced by HR and EF (resp. r = 0.51 and r = 0.50, P < 0.05). TPFR however was not influenced by HR and EF, whereas AC was positively correlated with HR (r = 0.79, P < 0. 01). Conclusions. Radionuclide angiography is a reliable and reproduci ble method to assess parameters of diastolic left ventricular filling in individual patients. It may therefore be used to serially follow di astolic function. When used for interindividual comparison the depende ncy of RNA derived left ventricular filling parameters on age, HR and EF should however be considered.