Long-term prognosis of left ventricular re-remodeling after surgery of ischemic cardiomyopathy: the potential of tomographic radionuclide ventriculography

Aim. To assess the potential of stress tomographic radionuclide ventriculography (T-RVG) in long-term prognosis of left ventricular (LV) re-remodeling after surgery of ischemic cardiomyopathy.Material and methods. Thirty patients with ischemic cardiomyopathy, before surgical treatment, underwent resting T-RVG and with increasing doses of dopamine (5/10/15 pg/kg/min (5 min/dose). All patients underwent two-dimensional echocardiography before surgery, in the short- (7-14 days) and long-term postoperative period. In the long-term postoperative period (476±36 days), the patients were divided into two groups: group 1 (n=19) — patients with ongoing LV remodeling (increase in the LV end-systolic volume (ESV) or decrease <10% relatively short-term postoperative period), group 2 (n=11) — patients with decreased LV ESV >10%.Results. The results revealed significant differences between the groups in the dynamics (Δ) of the LV ejection fraction (EF) (%) (2 (2;8); 11 (5;12), p=0,02), peak ejection rate (%) (32 (14;51); 63 (34;79), p=0,009), LV dyssynchrony (PSDo (3 (0;7); -2 (-9;3), p=0,004); Entropy (%) (2 (-1;6); 0 (-4;2), p=0,01)). Univariate regression showed that ΔLVEF (odds ratio (OR), 0,88; confidence interval (CI), 0,8; 0,97; p=0.008), ΔLVPSD (OR, 1,13; CI, 1,03; 1,25; p=0,005), and coronary stenosis >75% (OR, 4,25; CI, 1,57; 11,48; p=0,001) had a predictive value. According to the ROC-analysis, the sensitivity, specificity, and AUC were 87%, 64% and 0,727 for ΔLVPSD (threshold >-1); 84%, 46% and 0,691 for coronary stenosis >75% >75% (threshold >2); 65%, 82% and 0,674 for ΔLVEF (threshold ≤4), respectively. The logistic model, which included these parameters and the presence of diabetes, showed a significantly greater AUC (0,907, p<0,05) compared with these indicators taken separately.Conclusion. Preoperative values of ΔLVEF and ΔLVPSD obtained with stress T-RVG have prognostic significance in relation to LV long-term re-remodeling.

New Hybrid Method for Left Ventricular Ejection Fraction Assessment from Radionuclide Ventriculography Images

Background: In this paper, we propose a new efficient method of radionuclide ventriculography image segmentation to estimate the left ventricular ejection fraction. This parameter is an important prognostic factor for diagnosing abnormal cardiac function. Methods: The proposed method combines the Chan-Vese and the mathematical morphology algorithms. It was applied to diastolic and systolic images obtained from the Nuclear Medicine Department of Salah AZAIEZ Institute.In order to validate our proposed method, we compare the obtained results to those of two methods of the literature. The first one is based on mathematical morphology, while the second one uses the basic Chan-Vese algorithm. To evaluate the quality of segmentation, we compute accuracy, positive predictive value and area under the ROC curve. We also compare the left ventricle ejection fraction estimated by our method to that of the reference given by the software of the gamma-camera and validated by the expert, using Pearson’s correlation coefficient, ANOVA test and linear regression. Results and conclusion: Static results show that the proposed method is very efficient in the detection of the left ventricle. The accuracy was 98.60%, higher than that of the other two methods (95.52% and 98.50%). Likewise, the positive predictive value was the highest (86.40% vs. 83.63% 71.82%). The area under the ROC curve was also the most important (0.998% vs. 0.926% 0.919%). On the other hand, Pearson's correlation coefficient was the highest (99% vs. 98% 37%). The correlation was significantly positive (p<0.001).

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

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.

P3360Quantitative assessment of tricuspid regurgitation using right and left ventricular stroke volumes obtained from tomographic equilibrium radionuclide ventriculography

Background Quantitative assessment of valve regurgitation using volumetric method by comparing right and left ventricular stroke volumes is still under investigations. Aims To investigate the accuracy of tomographic equilibrium radionuclide ventriculography (t-ERV) for the quantification of tricuspid regurgitation (TR). Methods and results Sixty-one patients (44 men; mean age 59±12 years) who underwent both t-ERV and transthoracic echocardiography (TTE) studies within 2 weeks for right ventricular systolic function assessment were eligible for inclusion. A sub-group of 22 patients underwent both t-ERV and CMR. Patients with mitral/aortic regurgitation by TTE were excluded of the study. TR regurgitant volume (RVol) was calculated using the proximal isovelocity surface area (PISA) method from TTE and the volumetric method (right ventricular stroke volume minus left ventricular stroke volume) from t-ERV. RVol tended to be higher using the ERV volumetric method as compared to PISA method (43±35 and 35±33 ml, respectively; P<0.0001). There was a significant correlation between RVol as assess by ERV and by TTE (R=0.95, P<0.0001). Intraclass correlation coefficient between TTE and ERV for TR quantification was 0.95 (P<0.0001). Among patients who underwent CMR, the correlation between RVol obtained by TTE and by t-ERV and CMR were R=0.81 and R=0.75, respectively (all P<0.0001), without difference between the two correlations (P=0.263). Linear regression (left) and Bland-Altma Conclusion TR assessment using the t-ERV correlates well with PISA from TTE in patients referred for right ventricular systolic function assessment.