Radionuclide assessment of a normal left ventricular response to exercise in patients without evidence of heart disease

Abstract

The aim of this study was to define normal left ventricular performance at rest and during supine bicycle exercise with equilibrium radionuclide ventriculography in a normal population other than young healthy volunteers. Thirty-one patients (mean age 45 years +/- 9 SD) with chest pain of varying origin and no evidence of heart disease proven by means of noninvasive and invasive techniques were studied. Left ventricular ejection fraction (LVEF) at rest averaged 0.64 +/- 0.07 SD and increased with peak exercise to 0.73 +/- 0.08 SD (P less than 0.005). Change in LVEF from rest to maximum exercise ranged within 0-0.19. Six patients (19%) failed to augment LVEF with exercise to more than 0.05; none of the patients dropped LVEF during exercise. Multivariate analysis revealed no significant predictors of LVEF response to exercise. However, there was a tendency that resting LVEF and enddiastolic volume index with exercise might influence LVEF response to exercise. Peak left ventricular ejection rate (LVER) at rest averaged 3.3 s-1 +/- 0.6 SD and increased to 5.1 s-1 +/- 1.1 SD (P less than 0.005) with exercise. Peak left ventricular early filling rate (LVFR) was 2.8 s-1 +/- 0.6 SD at rest and was measured 5.5 s-1 +/- 1.3 SD at maximum exercise (P less than 0.005). Left ventricular enddiastolic volume (EDV) did not change significantly from rest to maximum exercise, whereas left ventricular endsystolic volume (ESV) decreased to 79% +/- 19 SD (P less than 0.01) of the value at rest.(ABSTRACT TRUNCATED AT 250 WORDS)

Feasibility and reproducibility of biventricular volumetric assessment of cardiac function during exercise using real‐time radial k‐t SENSE magnetic resonance imaging

“…LV and RV EDV did not increase during exercise; RV EDV actually decreased slightly at the highest Hence, in the absence of an increase in EDV, the improvement in SV is most likely a reflection of increased contractility rather than a result of the FrankStarling mechanism and more favorable muscle fiber stretch. These results are in keeping with previous reports of studies using radionuclide (17)(18)(19) and MRI (7) techniques and describe the physiological response to exercise seen in young adults (20). Therefore, we believe that the described exercise protocol represents effective and physiological modality for cardiac stress testing.…”

Radionuclide Ventriculography in Normal Volunteers Performing Graded Supine Bicycle Exercise

“…This was also noted by Schoen et al [14] and Manyari et al [16] in studies of normal subjects undergoing supine bicycle exercise. However, Steingart et al [10] reported an increase in diastolic volume in the early stages of both supine and upright exericse, with no significant changes in the later stages.…”

Left Ventricular Function at Rest, during Exercise and Recovery Period in Trained Athletes: Assessment with Radionuclide Angiography

“…This increase in EF, although not marked, was significant in our athletes. The moderate increase in EF can be ex plained by the observation [6] that EF values at rest in our trained athletes were just above those observed in normal subjects [7], while other studies [8,9] demon strated a similarity in the resting values between normal untrained subjects and athletes. Moreover, an increase of greater than 5 % in EF values during exercise in nor mal subjects is seldom not seen, thus suggesting that these limits are an artificial and arbitrary line of discrim ination between normal and abnormal responses, put ting in doubt its specificity [10,11].…”

“…At intermediate exercise workload E-I, a slight in crease in EF was induced which tended to increase pro gressively [5,6] towards E-II and during RP. This increase in EF, although not marked, was significant in our athletes.…”

“…Moreover, an increase of greater than 5 % in EF values during exercise in nor mal subjects is seldom not seen, thus suggesting that these limits are an artificial and arbitrary line of discrim ination between normal and abnormal responses, put ting in doubt its specificity [10,11]. One other explana tion for this moderate increase in EF could be the fact that the study was carried out in supine position, and this has been shown to be capable of inducing a higher resting value with a decreased rise during exercise in EF [6]. The mild increase in EF at E-I can also derive from an increased isometric component of the initial effort, associated with a slight increase in diastolic arterial pres sure and therefore in the afterload [12], The more marked increase in EF at E-II related to the sharper decrease in diastolic arterial pressure, associated with a higher adrenergic tone induced by exercise [13], This increase in sympathetic activity presumably continued briefly, along with the decrease in afterload, during the RP with an associated persistent increase in EF.…”