Aim      To evaluate the predictive value of indexes of left ventricular mechanical dyssynchrony (MD) as determined by data of electrocardiogram (ECG)-gated myocardial perfusion scintigraphy (ECG-MPS) for prediction of the efficacy of resynchronization therapy (RT) in patients with chronic heart failure (CHF). Material and methods  This prospective study included 32 patients with nonischemic CHF and standard indications for RT. All patients underwent complete clinical an instrumental examination, including 24-h ECG monitoring and echocardiography (EchoCG). In order to evaluate the left ventricular (LV) myocardial perfusion, contractile function, and MD, myocardial perfusion scintigraphy was performed for all patients at rest prior to RT. In addition to the perfusion defect size at rest and hemodynamic parameters, LV MD was determined. The following indexes were used for analysis of dyssynchronization: phase standard deviation (PSD), phase histogram bandwidth (HBW), and phase histogram asymmetry and steepness. The treatment efficacy was evaluated by the clinical status of patients (clinical condition evaluation scale for CHF patient) and EchoCG at 6 months following RT. The criteria for a positive response to RT were an increase in LV ejection fraction (EF) by 5% and/or a decrease in the LV end-diastolic volume by 15% compared to preoperative values. Results According to ECG-MPS findings, all patients had scintigraphic signs of severe CHF with dilated LV cavity (end-diastolic volume, EDV 246 [217; 269] ml) and also of pronounced mechanical and electrical dyssynchrony. The values of mechanical dyssynchrony were PSD 53 [41; 61], HBW 176 [136; 202], asymmetry 1.62 [1.21; 1.89], and steepness 2.81 [1.21; 3.49]. The QRS duration was 165 [155; 175] msec. Furthermore, the LV perfusion was moderately impaired (perfusion defect size 4 [3; 10] %). Mean follow-up duration after implantation of the resynchronizing device was 6±1.7 mos. According to the selected criteria, 20 (63 %) patients were considered as responders and 12 (37 %) patients as non-responders. Before implantation of the cardiac synchronizing device, responders and non-responders differed only in LV MD (PSD 44 [35; 54] vs. 63 [58; 72]; p=0.0001); HBW 158 [118; 179] vs. 205 [199; 249]; p=0.0001; asymmetry 1.77 [1.62; 2.02] vs. 1.21 [0.93; 1.31]; p=0.0001; steepness 3.03 [2.60; 3.58] vs. 1.21 [0.19; 1.46]; p=0.0001), respectively. A one-factor logistic regression analysis showed that MD values were statistically significant predictors of a positive response to RT. A multi-factor logistic analysis of phase histogram steepness (odds ratio, OR 1.196; 95 % confidence interval, CI 1.04–1.37) and PSD (OR 0.67; 95 % CI 0.47–0.97) were identified as independent predictors for the response to RT. According to results of the ROC analysis, a PSD 1.54 may predict the effectiveness of RT (AUC= 0.92; р=0.0001). Conclusion      LV MD parameters determined with ECG-MPS allow predicting the effectiveness of RT in patients with nonischemic CHF. In this patient group, high values of standard deviation and low values of phase histogram steepness were independent predictors for the absence of response to RT after 6 mos. of follow-up.

Cardiac resynchronization therapy (CRT) is one of the methods of treating patients with chronic heart failure, which can reduce the mortality rate of this group. Scintigraphic assessment of sympathetic myocardial innervation allows us to evaluate the heart failure prognosis and the effectiveness of interventional treatment. The method is based on use of the radiopharmaceutical 123 I-methiodiobenzylguanidine (123 I-MIBG), which is a structural analogue of norepinephrine and is able to selectively accumulate in the sympathetic nerve endings. This review includes a brief description of norepinephrine metabolism and pharmacokinetics of 123 I-MIBG in the sympathetic nerve ending, a brief description of the study methodology and the clinical significance of this method in patients with heart failure. Particular attention is paid to the possibilities of using this method in patients with severe chronic heart failure before and after CRT.

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%.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 (PSD^o (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.

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%.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 (PSD^o (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.

Electrical and mechanical dyssynchrony (MD) underlies left ventricular (LV) contractile dysfunction in patients with heart failure (HF) and left bundle branch block (LBBB). In some cases, cardiac resynchronization therapy (CRT) almost completely reverses LV contractile dysfunction. The LBBB electrocardiographic Strauss criteria and MD assessment were proposed to improve CRT response. However, using these techniques separately does not improve LV contraction in 20–40% of patients after CRT device implantation. We aimed to evaluate whether the combined use of electrocardiography (ECG), speckle-tracking echocardiography (STE) and cardiac scintigraphy could improve the prognosis of CRT super-response in patients with HF and Strauss LBBB criteria during a 6-month follow-up period. The study prospectively included patients with HF, classified as New York Heart Association (NYHA) functional class (FC) II–III in sinus rhythm with Strauss LBBB criteria and reduced left ventricular ejection fraction (LVEF). Before and 6 months after CRT device implantation, ECG, STE and cardiac scintigraphy were performed. The study’s primary endpoint was the NYHA class improvement ≥ 1 and left ventricle end systolic volume decrease > 30% or LVEF improvement > 15% after 6 months of CRT. Based on collected data, we developed a prognostic model regarding the CRT super-response. Out of 54 (100.0%) patients, 39 (72.2%) had a CRT super-response. Patients with CRT super-response were likelier to have a greater S wave amplitude in V₂ lead (p = 0.004), higher rates of global longitudinal strain (GLS) (p = 0.001) and interventricular delay (IVD) (p = 0.005). Only three indicators (S wave amplitude in V₂ lead, GLS and IVD) were independently associated with CRT super-response in univariable and multivariable logistic regression. We created a prognostic model based on the logistic equation and calculated a cut-off value (>0.73). The resulting ROC curve revealed a discriminative ability with an AUC of 0.957 (sensitivity 87.2%; specificity 100.0%). The electrical and mechanical dyssynchrony assessment using ECG, STE and cardiac scintigraphy is useful in the prediction of CRT super-response in patients with HF and Strauss LBBB criteria during a 6-month follow-up period. Our prognostic model can identify patients who are super-responders to CRT.