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Left ventricular (LV) function during prolonged constant-load exercise (EX) in cardiac patients (PTS)
Journal of Nuclear Cardiology Volume 6, Number 1, Part 2
Abstracts Wednesday afternoon, April 21, 1999
S 105
54.16
54.18
RELIABILITY OF EJECTION FRACTION (EF) CALCULATIONS AT DIFFERENT HEART RATE, MATRIX AND FRAMES FORMAT - AN ASSESSMENT OF VANDERBILT DYNAMIC CARDIAC PHANTOM
RIGHT VENTRICULAR FUNCTION AT REST AND EXERCISE IN HEMODIALYSIS PATIENTS AFTER CORRECTION OF ANEMIA WITH RECOMBINANT ERYTHROPOIETIN
N. Top_uzo~ A. Rusid, I. Kamer. Dept. of Nuclear Medicine, Osijek University Hospital, Osijek, Croatia The aim of the present study was to evaluate the potential effects of different heart rate, frames and matrix format on measurements of global and regional EF as determined by radionuclide ventriculography of Vanderbilt cardiac phantom, and intra- and interobserver variations. The phantom consists of two parts with heart-to-background activity adjusted to that obtained in clinical studies. Three attennuators simulate low, medium and high EF The data were acquired with 16 and 32 frames/cycle in 64x64 and 128x128 matrix. The range of frequencies used was from 60 to 180 per minute in steps of 20 beats.No significant difference was found in the EF determined at different frequencies in both matrix size and both frames format for all three predicted EF. Variations of EF at different heart rate were from minimum 2.3% (medium EF) to maximum 7.6% (low and high EF). There were no significant difference in intra- and interobserver variation for determination of EF. In conclusion, our data indicated that EF can be accurately obtained at wide range of heart rate, and is independent of matrix and frames format.
54.17 LEFT V E N T R I C U L A R (LV) FUNCTION D U R I N G PROLONGED CONSTANT-LOAD EXERCISE (EX) IN CARDIAC PATIENTS (PTS) R,Ajisaka, M.Ishiyama, S.Watanabe, H.Nishina, N.Takeyasu, I.Yamaguchi, Y.Sugishita. Institute of Health and Sports Sciences, University of Tsukuba, Tsukuba, Japan D e s p i t e e x t e n s i v e s t u d y o f LV f u n c t i o n d u r i n g i n c r e m e n t a l ex, t h e r e is l i t t l e k n o w n a b o u t LV f u n c t i o n d u r i n g p r o l o n g e d ex. So, LV f u n c t i o n during 30-min constant-load ergometer ex was e v a l u a t e d e v e r y 10 m i n i n 16 c a r d i a c p t s . Although cardiac output measured by dyedilution method maintained stable, a progressive increase in heart rate concomitant with a decline in stroke volume was observed after the 1 0 t h m i n o f e x . LV e j e c t i o n f r a c t i o n (LVEF) w a s essentially stable and end-diastolic count was decreased after the 10th rain of ex in radionuclide ventriculography ( RNV ) in those p t s . T h e " c a r d i o v a s c u l a r d r i f t " p r o b a b l y d u e to deceased ventricular preload occurred during prolonged constant-load ex in 8 pts with normal LVEF a s w e l l a s i n 8 p t s w i t h d e p r e s s e d LVEF. I n c o n c l u s i o n , t h e R N V is u s e f u l f o r e v a l u a t i o n o f LV f u n c t i o n d u r i n g p r o l o n g e d ex.
N. Topuzovid, V. Rupdi4 A. Rusid, Z Kamer. Dept. of Nuclear Meoh'cine, University Hospital, Osijek, Croatia The aim of the present study was to evaluate the potential The effects of correction of anemia with EPO on right ventricular function were evaluated in 19 hemodialysis patients with severe renal anemia (hematocrit < 0.25) by rest/stress radionuclide ventriculography before therapy, and at the time when target hemoglobin (Hb) reached 100 g/l. Mean Hb at initiation was 72 + 6 g/1 and increased to 111 -+ 11 during 3.5 +_ 1.5 months. Ejection fraction, peak ejection rate (PER) and time to PER showed no significant difference before and after treatment. While peak l-filing rate (PFR) remained unchanged during therapy (2.78 + 0.98 vs. 2.57 + 0.63 EDV/s), time to PFR was significantly prolonged from 163 4- 51 to 208 + 57 msec, p<0.02. Despite significant rise in maximal work load (26%) and exercise duration (30%) no significant difference was observed during exercise in examined parameters. In conclusion, right systolic function at rest and exercise was unchanged during correction of anemia with EPO in chronic hemodialysis patients, but right ventricular filling dynamics are altered during therapy.
54.19 RADIONUCLIDE LEFT VENTRICULAR VOLUME DETERMINATION: COMPARISON OF FOUR METHODS. N. Delahaye, M. Faraggi, D. Daou, L. Sarda, R. Lebtahi. Bichat hospital, Paris, France. Neninvasive equilibriumradionuclide angiography (RNA) determination of end-diastolic volume (EDV) using two geometric methods (ml and m2) and two semi-geometric count-proportional methods (m3 and m4) was compared with biplane contrast ventriculography(CV) performedwithin 48 hours. RNA was performedin left anterior oblique (LAO) projectionand in left profile (LP) in 21 patients with recent myocardial infarction. EDV determination methods, previously published and frequently used, were based on some assumptions, ml: EDV was assumed to consist of cylindral slices arranged perpendicularly to the long axis of the LV, each slice having the thickness of 1 pixel, m2: EDV was assumed to be a prolate ellipsoid, and was calculatedwith measa~c~nentsof l long (LP) and 2 short axes (LAO and LP). m3: LAO projection of LV was assumed to be equivalent to the projection of a spherical radioactive distribution, so EDV was related to the ratio of total LV counts to those within its hottest pixel. m4: LV was assumed to have a cylindral geometryat the level of its hottest pixel, and, with measurement of the LV horizontal short axis (LAO), calibration of counts per voxel was made, then EDV was calculated. Mean 5: SD (ml) r SEE (ml) SEE/mean Reproductibility CV 1175:28 ml 162 +46 0.85 I" 25 15.4 % 95.5 % m2 231 +_gl 0.75 I 55.6 24 % 93,4 % m3 188 + 56 0.79 I" 36.3 19.3 % 94.5 % m4 130 5:39 0.82 I" 23,8 18.3 % 95.1% °fp<0.001,SEE:standarderrorofestimate Globally all these methods yielded to rather high correlation coefficients. But all overestimated EDV, are very sensitive to the region of interest determination and make assumptions about the LV shape which could induce inaccuracyfor detecting slight EDV variations.
W E D N E S D A Y P M A P R I L
Abstracts Wednesday afternoon, April 21, 1999
S 105
54.16
54.18
RELIABILITY OF EJECTION FRACTION (EF) CALCULATIONS AT DIFFERENT HEART RATE, MATRIX AND FRAMES FORMAT - AN ASSESSMENT OF VANDERBILT DYNAMIC CARDIAC PHANTOM
RIGHT VENTRICULAR FUNCTION AT REST AND EXERCISE IN HEMODIALYSIS PATIENTS AFTER CORRECTION OF ANEMIA WITH RECOMBINANT ERYTHROPOIETIN
N. Top_uzo~ A. Rusid, I. Kamer. Dept. of Nuclear Medicine, Osijek University Hospital, Osijek, Croatia The aim of the present study was to evaluate the potential effects of different heart rate, frames and matrix format on measurements of global and regional EF as determined by radionuclide ventriculography of Vanderbilt cardiac phantom, and intra- and interobserver variations. The phantom consists of two parts with heart-to-background activity adjusted to that obtained in clinical studies. Three attennuators simulate low, medium and high EF The data were acquired with 16 and 32 frames/cycle in 64x64 and 128x128 matrix. The range of frequencies used was from 60 to 180 per minute in steps of 20 beats.No significant difference was found in the EF determined at different frequencies in both matrix size and both frames format for all three predicted EF. Variations of EF at different heart rate were from minimum 2.3% (medium EF) to maximum 7.6% (low and high EF). There were no significant difference in intra- and interobserver variation for determination of EF. In conclusion, our data indicated that EF can be accurately obtained at wide range of heart rate, and is independent of matrix and frames format.
54.17 LEFT V E N T R I C U L A R (LV) FUNCTION D U R I N G PROLONGED CONSTANT-LOAD EXERCISE (EX) IN CARDIAC PATIENTS (PTS) R,Ajisaka, M.Ishiyama, S.Watanabe, H.Nishina, N.Takeyasu, I.Yamaguchi, Y.Sugishita. Institute of Health and Sports Sciences, University of Tsukuba, Tsukuba, Japan D e s p i t e e x t e n s i v e s t u d y o f LV f u n c t i o n d u r i n g i n c r e m e n t a l ex, t h e r e is l i t t l e k n o w n a b o u t LV f u n c t i o n d u r i n g p r o l o n g e d ex. So, LV f u n c t i o n during 30-min constant-load ergometer ex was e v a l u a t e d e v e r y 10 m i n i n 16 c a r d i a c p t s . Although cardiac output measured by dyedilution method maintained stable, a progressive increase in heart rate concomitant with a decline in stroke volume was observed after the 1 0 t h m i n o f e x . LV e j e c t i o n f r a c t i o n (LVEF) w a s essentially stable and end-diastolic count was decreased after the 10th rain of ex in radionuclide ventriculography ( RNV ) in those p t s . T h e " c a r d i o v a s c u l a r d r i f t " p r o b a b l y d u e to deceased ventricular preload occurred during prolonged constant-load ex in 8 pts with normal LVEF a s w e l l a s i n 8 p t s w i t h d e p r e s s e d LVEF. I n c o n c l u s i o n , t h e R N V is u s e f u l f o r e v a l u a t i o n o f LV f u n c t i o n d u r i n g p r o l o n g e d ex.
N. Topuzovid, V. Rupdi4 A. Rusid, Z Kamer. Dept. of Nuclear Meoh'cine, University Hospital, Osijek, Croatia The aim of the present study was to evaluate the potential The effects of correction of anemia with EPO on right ventricular function were evaluated in 19 hemodialysis patients with severe renal anemia (hematocrit < 0.25) by rest/stress radionuclide ventriculography before therapy, and at the time when target hemoglobin (Hb) reached 100 g/l. Mean Hb at initiation was 72 + 6 g/1 and increased to 111 -+ 11 during 3.5 +_ 1.5 months. Ejection fraction, peak ejection rate (PER) and time to PER showed no significant difference before and after treatment. While peak l-filing rate (PFR) remained unchanged during therapy (2.78 + 0.98 vs. 2.57 + 0.63 EDV/s), time to PFR was significantly prolonged from 163 4- 51 to 208 + 57 msec, p<0.02. Despite significant rise in maximal work load (26%) and exercise duration (30%) no significant difference was observed during exercise in examined parameters. In conclusion, right systolic function at rest and exercise was unchanged during correction of anemia with EPO in chronic hemodialysis patients, but right ventricular filling dynamics are altered during therapy.
54.19 RADIONUCLIDE LEFT VENTRICULAR VOLUME DETERMINATION: COMPARISON OF FOUR METHODS. N. Delahaye, M. Faraggi, D. Daou, L. Sarda, R. Lebtahi. Bichat hospital, Paris, France. Neninvasive equilibriumradionuclide angiography (RNA) determination of end-diastolic volume (EDV) using two geometric methods (ml and m2) and two semi-geometric count-proportional methods (m3 and m4) was compared with biplane contrast ventriculography(CV) performedwithin 48 hours. RNA was performedin left anterior oblique (LAO) projectionand in left profile (LP) in 21 patients with recent myocardial infarction. EDV determination methods, previously published and frequently used, were based on some assumptions, ml: EDV was assumed to consist of cylindral slices arranged perpendicularly to the long axis of the LV, each slice having the thickness of 1 pixel, m2: EDV was assumed to be a prolate ellipsoid, and was calculatedwith measa~c~nentsof l long (LP) and 2 short axes (LAO and LP). m3: LAO projection of LV was assumed to be equivalent to the projection of a spherical radioactive distribution, so EDV was related to the ratio of total LV counts to those within its hottest pixel. m4: LV was assumed to have a cylindral geometryat the level of its hottest pixel, and, with measurement of the LV horizontal short axis (LAO), calibration of counts per voxel was made, then EDV was calculated. Mean 5: SD (ml) r SEE (ml) SEE/mean Reproductibility CV 1175:28 ml 162 +46 0.85 I" 25 15.4 % 95.5 % m2 231 +_gl 0.75 I 55.6 24 % 93,4 % m3 188 + 56 0.79 I" 36.3 19.3 % 94.5 % m4 130 5:39 0.82 I" 23,8 18.3 % 95.1% °fp<0.001,SEE:standarderrorofestimate Globally all these methods yielded to rather high correlation coefficients. But all overestimated EDV, are very sensitive to the region of interest determination and make assumptions about the LV shape which could induce inaccuracyfor detecting slight EDV variations.
W E D N E S D A Y P M A P R I L