Radionuclide ventriculography phase analysis for risk stratification of patients undergoing cardiotoxic cancer therapy

Abstract

Background Accurate diagnostic tools to identify patients at risk of cancer therapy-related cardiac dysfunction (CTRCD) are critical. For patients undergoing cardiotoxic cancer therapy, ejection fraction assessment using radionuclide ventriculography (RNVG) is commonly used for serial assessment of left ventricular (LV) function. Methods In this retrospective study, approximate entropy (ApEn), synchrony, entropy, and standard deviation from the phase histogram (phase SD) were investigated as potential early markers of LV dysfunction to predict CTRCD. These phase parameters were calculated from the baseline RNVG phase image for 177 breast cancer patients before commencing cardiotoxic therapy. Results Of the 177 patients, 11 had a decline in left ventricular ejection fraction (LVEF) of over 10% to an LVEF below 50% after treatment had commenced. This patient group had a significantly higher ApEn at baseline to those who maintained a normal LVEF throughout treatment. Of the parameters investigated, ApEn was superior for predicting the risk of CTRCD. Combining ApEn with the baseline LVEF further improved the discrimination between the groups. Conclusions The results suggest that RNVG phase analysis using approximate entropy may aid in the detection of sub-clinical LV contraction abnormalities, not detectable by baseline LVEF measurement, predicting a subsequent decline in LVEF.

Optimising approximate entropy for assessing cardiac dyssynchrony with radionuclide ventriculography

“…ApEn was used for serial assessment of RNVG images for a small study of breast cancer patients, where a significant change in ejection fraction and ApEn was demonstrated over the course of treatment. Recent work carried out by our group demonstrated the predictive value of ApEn combined with LVEF for baseline assessment of breast cancer patients, before undergoing cardiotoxic chemotherapy [5].…”

“…Left ventricular dyssynchrony can be quantified using several different phase parameters, including the standard deviation of the phase pixel values (phase SD) and the bandwidth of the phase histogram. Approximate entropy (ApEn) has been applied to phase images to quantify dyssynchrony [4,5], but to date no optimisation for this application has been published. The selection of input values used will significantly affect the value of ApEn, therefore, this work aims to optimise ApEn for application to nuclear cardiology images and demonstrate the effect of changing input parameters.…”

Beta-blockers and mechanical dyssynchrony in heart failure assessed by radionuclide ventriculography

“…Various measures to quantify dyssynchrony, including synchrony, entropy, approximate entropy (ApEn), and standard deviation of the phase histogram (phase SD), can be used to provide additional information from planar RNVG images with high reproducibility. [16][17][18][19][20][21][22][23] Sample entropy (SampEn) 24 is novel for this application and has not been previously investigated.…”

Early prediction of chemotherapy-induced cardiotoxicity

“…The parameters discussed include peak filling rate, time to peak filling rate and approximate entropy. [6][7][8][9][10][11][12][13] These parameters are all derived from RNA data without any additional dose or change to imaging technique or protocol. To date, the research is limited to small single-center studies with some promising results.…”