Browsing by Author "Milasinovic, Goran (9238319300)"

Heart rate (HR) asymmetry is a dynamic phenomenon related to the interplay of dominant regulatory mechanisms of cardiovascular system which operate over different scales of observation. The aim of this work is to examine asymmetry phenomenon in heart failure (HF) patients with sinus rhythm. We computed Guzik's index of heart rate asymmetry related to HR deceleration (C-{d}) from the Poincaré plot (Pp) analysis extended up to 20th order. In the control group asymmetry is maintained over all orders of the Pp. In HF patients with asymmetric properties, C-{d} is reduced in the range between 2ndand 5th order of the Pp analysis, compared the control subjects. More, this method revealed two clusters of HF patients. In conclusion, proposed new approach can be applied to reveal alterations in the behavior of the cardiovascular control mechanisms in pathological conditions. © 2020 IEEE.

Heart rate (HR) asymmetry is a dynamic phenomenon related to the interplay of dominant regulatory mechanisms of cardiovascular system which operate over different scales of observation. The aim of this work is to examine asymmetry phenomenon in heart failure (HF) patients with sinus rhythm. We computed Guzik's index of heart rate asymmetry related to HR deceleration (C-{d}) from the Poincaré plot (Pp) analysis extended up to 20th order. In the control group asymmetry is maintained over all orders of the Pp. In HF patients with asymmetric properties, C-{d} is reduced in the range between 2ndand 5th order of the Pp analysis, compared the control subjects. More, this method revealed two clusters of HF patients. In conclusion, proposed new approach can be applied to reveal alterations in the behavior of the cardiovascular control mechanisms in pathological conditions. © 2020 IEEE.

Aims: Selection of patients who are viable candidates for cardiac resynchronization therapy (CRT), prediction of the response to CRT as well as an optimal definition of a favorable response, all require further exploration. The purpose of this study was to evaluate the interplay between the prediction of the response to CRT and the definition of a favorable outcome. Methods: Seventy patients who received CRT were included. All patients met current guideline criteria for CRT. Forty-three echocardiographic parameters were evaluated before CRT and at 1, 3, 6, and 12 months. M-mode, 2D echocardiography, and Doppler imaging were used to quantify left ventricular (LV) systolic and diastolic function, mitral regurgitation, right ventricular systolic function, pulmonary artery pressure, and myocardial mechanical dyssynchrony. The following definitions of a favorable CRT response were used: left ventricular ejection fraction (LVEF) improvement more >5% acutely following CRT, LVEF improvement >20% at 12-month follow-up, and a LV end-systolic volume (LVESV) decrease >15% at 12-month follow-up. Results: For the LVEF improvement >5%, the best predictor was isovolumetric relaxation time (IVRT; P=.035). For improvement of LVEF >20%, the best predictors were left ventricular stroke index (LVSI; P=.044) and left ventricular fractional shortening (LVFS; P=.031). For the drop in left ventricular systolic volume (LVESV >15%), the best predictor was septal-to-lateral wall delay (ΔT) (P=.043, RR=1.023, 95% CI for RR=1.001-1.045). Conclusion: The definition of a favorable CRT response influenced the optimal predictor variable(s). Standardization of defining a favorable response to CRT is needed to guide clinical decision making processes. © 2017, Wiley Periodicals, Inc.

Objectives: The aim of this study was to assess the performance of echocardiographic parameters to predict response to cardiac resynchronization therapy (CRT). Background: CRT reduces morbidity and mortality due to the proper selection of candidates for CRT. Methods: The 12-month trial was performed on 70 optimally medicated patients with standard inclusion criteria: NYHA class III or IV heart failure, left ventricular ejection fraction (LVEF) ≤ 35%, and QRS a 120 ms. All parameters were evaluated by conventional and tissue Doppler-based methods. Indicator of positive CRT response was more than 20% in improvement of LVEF. Results: LVEF increased >20% in 42 patients. Out of 43 tested baseline echocardiographic parameters, 12 showed statistical difference between responders and nonresponders. Out of these 12 parameters, six (LVSV, LVSI, LVFS, RVd, VPMR, and PISA) had modest to moderately good ability to predict LVEF response with sensitivity ranging from 62.2% to 82.4%, and specificity ranging from 56.5% to 81.2%. For those parameters, the area under the receiver-operating characteristic curve for positive response to CRT was a;circ0.76. Multivariate regression analysis resulted in selection of LVSI and LVFS as possible predictive independent parameters for a good response. The cutoff value for LVSI was 38.7 mL/m 2 (P = 0.045) and for LVFS was 13% (P = 0.032). Conclusions: Contribution of LVSI and LVFS is to be confirmed in larger trials. Simplicity of their assessment by conventional echocardiography could be an argument for adding them to the inclusion criteria for CRT in severe heart failure patients. © 2011, Wiley Periodicals, Inc.

Aims The aim of the study wasto assess the value of coronaryflowreserve (CFR) for predicting improvement of left ventricular function after cardiac resynchronization therapy (CRT). Methods and results Study population included 40 patients (mean age 58+9 years) with heart failure (ejection fraction 25, 7+5, 4%) and QRS duration of 158+22 ms, planned for CRT. Before and after CRT implantation, CFR was measured non-invasively during hyperaemia induced with adenosine. Responders were defined by decrease in end-systolic volume ≥15%. Followup echocardiography and CFR measurements were obtained after 6 months. At baseline there was no significant difference in left ventricular ejection fraction (LVEF), QRS duration, 6 min walk test distance and coronary flowvelocity at rest betweenresponder (n = 26) vs. non-responder group (n = 14, P = ns). BeforeCRTimplantation, responders compared with non-responders, showed a greater increase in coronary flow velocity during hyperaemia, and consequently higher CFR: 2.41+0.60 vs. 1.61+0.45 (P = 0.001). There was significant correlation between CFR before CRT implantation and LVEFafter 6 months (r = 0.545, P = 0.001). End-diastolic, end-systolic left ventricular diameter, andCFRbeforeCRT were predictors of LVfunctional improvement. By multivariate analysis, onlyCFRbeforeCRTwas independent predictor of left ventricular recovery in the follow-up period (P = 0.001). Conclusion Our results demonstrate that preserved CFR in patients with dilated cardiomyopathy is predictive of left ventricular improvement after CRT implantation. © The Author 2014.

Background: In the majority of patients with a wide QRS complex and heart failure resistant to optimal medical therapy, cardiac resynchronization therapy (CRT) leads to rever se ventricular remodeling and possibly to changes in cardiac collagen synthesis and degradation. We investigated the relationship of biomarkers of myocardial collagen meta bolism and volumetric response to CRT. Methods: We prospectively studied 46 heart failure patients (mean age 61±9 years, 87% male) who underwent CRT im plantation. Plasma concentrations of amino-terminal pro peptide type I (PINP), a marker of collagen synthesis, and carboxy-terminal collagen telopeptide (CITP), a marker of collagen degradation, were measured before and 6 months after CRT. Response to CRT was defined as 15% or greater reduction in left ventricular end-systolic volume at 6-month follow-up. Results: Baseline PINP levels showed a negative correlation with both left ventricular end-diastolic volume (r=-0.51; p=0.032), and end-systolic diameter (r=-0.47; p=0.049). After 6 months of device implantation, 28 patients (61%) responded to CRT. No significant differences in the base-line levels of PINP and CITP between responders and nonresponders were observed (p>0.05 for both). During follow-up, responders demonstrated a significant increase in serum PINP level from 31.37±18.40 to 39.2±19.19 μg/L (p=0.049), whereas in non-responders serum PINP levels did not significantly change (from 28.12±21.55 to 34.47±18.64 μg/L; p=0.125). There were no significant changes in CITP levels in both responders and non-responders (p>0.05). Conclusions: Left ventricular reverse remodeling induced by CRT is associated with an increased collagen synthesis in the first 6 months of CRT implantation.

Background: In the majority of patients with a wide QRS complex and heart failure resistant to optimal medical therapy, cardiac resynchronization therapy (CRT) leads to rever se ventricular remodeling and possibly to changes in cardiac collagen synthesis and degradation. We investigated the relationship of biomarkers of myocardial collagen meta bolism and volumetric response to CRT. Methods: We prospectively studied 46 heart failure patients (mean age 61±9 years, 87% male) who underwent CRT im plantation. Plasma concentrations of amino-terminal pro peptide type I (PINP), a marker of collagen synthesis, and carboxy-terminal collagen telopeptide (CITP), a marker of collagen degradation, were measured before and 6 months after CRT. Response to CRT was defined as 15% or greater reduction in left ventricular end-systolic volume at 6-month follow-up. Results: Baseline PINP levels showed a negative correlation with both left ventricular end-diastolic volume (r=-0.51; p=0.032), and end-systolic diameter (r=-0.47; p=0.049). After 6 months of device implantation, 28 patients (61%) responded to CRT. No significant differences in the base-line levels of PINP and CITP between responders and nonresponders were observed (p>0.05 for both). During follow-up, responders demonstrated a significant increase in serum PINP level from 31.37±18.40 to 39.2±19.19 μg/L (p=0.049), whereas in non-responders serum PINP levels did not significantly change (from 28.12±21.55 to 34.47±18.64 μg/L; p=0.125). There were no significant changes in CITP levels in both responders and non-responders (p>0.05). Conclusions: Left ventricular reverse remodeling induced by CRT is associated with an increased collagen synthesis in the first 6 months of CRT implantation.