Resynchronization Therapy In Patients Research Articles

Conduction System Pacing: Hope, Challenges, and the Journey Forward.

Cardiac pacing has evolved in recent years currently culminating in the specific stimulation of the cardiac conduction system (conduction system pacing, CSP). This review aims to provide a comprehensive overview of the available literature on CSP, focusing on a critical classification of studies comparing CSP with standard treatment in the two fields of pacing for bradycardia and cardiac resynchronization therapy in patients with heart failure. The article will also elaborate specific benefits and limitations associated with CSP modalities of His bundle pacing (HBP) and left bundle branch area pacing (LBBAP). Based on a growing number of observational studies for different indications of pacing therapy, both CSP modalities investigated are advantageous over standard treatment in terms of narrowing the paced QRS complex and preserving or improving left ventricular systolic function. Less consistent evidence exists with regard to the improvement of heart failure-related rehospitalization rates or mortality, and effect sizes vary between HBP and LBBAP. LBBAP is superior over HBP in terms of lead measurements and procedural duration. With regard to all reported outcomes, evidence from large scale randomized controlled clinical trials (RCT) is still scarce. CSP has the potential to sustainably improve patient care in cardiac pacing therapy if patients are appropriately selected and limitations are considered. With this review, we offer not only a summary of existing data, but also an outlook on probable future developments in the field, as well as a detailed summary of upcoming RCTs that provide insights into how the journey of CSP continues.

Predictors of responders to cardiac resynchronization therapy in patients with non-left bundle branch block with mid-wide QRS duration

Abstract Background Cardiac resynchronization therapy (CRT) is useful for patients with severe heart failure with dyssynchrony of left ventricular contraction, significantly reducing total mortality or heart failure rehospitalization. In patient with left bundle branch block (LBBB) or QRS duration (QRSd) ≥ 150 ms, CRT is a well-established therapy at guidelines in Japan and other countries. However, CRT may be more useful and effective in Asian patients with middle range wide QRSd, because of smaller body size than in the West. Few reports have shown the usefulness and efficacy of CRT in patients with non-LBBB and middle range wide QRS duration (mid-wide QRSd). Purpose To evaluate the predictors of CRT responders in heart failure patients with non LBBB and mid wide QRSd. Methods We retrospectively studied 174 consecutive patients who underwent a denovo CRT device implantation at two institutions between September 2013 and March 2023. Follow up echocardiography examination could be performed after 150 days postoperatively. CRT responders were defined as a decrease in left ventricular end systolic volume ≥15% on echocardiography. We plotted thereceiver operating characteristic (ROC) curve for predicting CRT responders. The area under the curve (AUC) was calculated to determine the best cut off value. Results A total of 34 patients with non LBBB and 120≤ QRSd <150 ms were enrolled in this study. Sixteen of 34 (47%) patients were the responders for CRT. There was no significant difference in gender between the responder and non responder groups (p=0.274). Non ischemic cardiomyopathy was more prevalent in the responder group (p=0.046). The ROC curve analysis confirmed that 0.809 was the better optimal cut off value of QRSd/left ventricular end diastolic volume (LVEDV) for predicting CRT responders (AUC = 0.688). The multivariate analysis demonstrated that QRSd/LVEDV was significantly associated with CRT responders [odds ratio (OR) 9.88, 95% confidence interval 1.51 64.90, p = 0.017]. Conclusion The corrected QRSd for heart size using LVEDV could be the independent predictor of CRT responders in Japanese patients with non LBBB and mid wide QRSd.

The use of left bundle branch pacing as a bail-out in case of CRT pacing failure: a case series

Abstract Introduction LBBB pacing has emerged as a novel alternative to CS pacing for cardiac resynchronization therapy in patients with heart failure. Purpose We hereby present a series of four cases wherein the use of LBB pacing, although not initially planned as first choice, was able to overcome a variety of different limitations of traditional CRT pacing. Presentation Patient #1 was an 81-year old man with a history of ischemic HF and AF who was admitted with recurring episodes of sustained ventricular tachycardia (VT) below the detection zone of the CRT-D that had been implanted 11 years ago. Interrogation of the device revealed fracture in the RV lead, intact values of the RV defibrillation coil and inability to capture from an LV lead in an anterior vein. Following initial stabilization the patient underwent successful LBB lead implantation combined with a new RV pace-sense lead as backup due to acceptable but non-optimal LBB lead values attributed to ischemic septal scarring. We were able to retain the previous CRT-D device by relegating the LBB lead to the atrial port and with the use of DDDR programming with custom AV delay values in order to achieve LBB pacing with RV pacing as backup. Patient #2 was a 51-year old man with a history of ischemic HF and permanent AF with a previously implanted CRT-D who was also admitted due to episodes of VT. Device interrogation revealed high threshold of an LV lead located in an anterior vein. The patient underwent supplementary LBB lead implantation which was then connected to the atrial port of the pre-existing CRT-D device, providing primarily LBB pacing with RV pacing backup through the use of custom DDDR programming same as in the previous case. Patient #3 was a 71–year old man with newly-diagnosed ischemic cardiomyopathy and multiple episodes of hemodynamically unstable VT that persisted even after successful reperfusion, necessitating VT ablation. The patient had narrow QRS at baseline and was not eligible for CRT-D, however after medical therapy to suppress ventricular arrhythmias the patient seemed prone to developing LBBB-like QRS widening. The decision was made to proceed with standard ICD implantation and combine a standard defibrillation lead with an LBB lead through the use of a DF1 port, so as to be able to provide LBB pacing as needed in the future. Patient #4 was a 62-year old man with a history of hypertrophic cardiomyopathy and HF with extensive apical scar scheduled for CRT-D implantation. CS venography during implantation revealed a single lateral vein draining the apical LV, lead was implanted but with no capture. An LBB pacing lead was successfully implanted and used instead of the LV lead in the conventional CRT-D set up. Conclusion In this case series we demonstrate that LBB pacing is a viable option as a bail-out in various cases of CRT pacing failure, including both septal scar and hypertrophy, as well as different anatomical substrates and CRT status.LBB pacing characteristics summary

Indications for Cardiac Resynchronization Therapy in Patients with Congenital Heart Disease.

Heart failure in patients with congenital heart disease (CHD) stems from unique causes compared with the elderly. Patients with CHD face structural abnormalities and malformations present from birth, leading to altered cardiac function and potential complications. In contrast, elderly individuals primarily experience heart failure due to age-related changes and underlying cardiovascular conditions. Cardiac resynchronization therapy (CRT) can benefit patients with CHD, although it presents numerous challenges. The complexities of CHD anatomy and limited access to appropriate venous sites for lead placement make CRT implantation demanding.

Techniques for Cardiac Resynchronization Therapy in Patients with Congenital Heart Disease.

Cardiac resynchronization therapy (CRT) for congenital heart disease has shown promising suucess as an adjunct to medical therapy for heart failure. While cardiac conduction defects and need for ventricular pacing are common in congential heart disease, CRT indications, techniques and long term outcomes have not been well establaished. This is a review of the techniques nad short term outcomes of CRT for the following complex congenital heart disease conditions: single ventricle physiology, systemic right ventricle, and the subpulmonic right ventricle.

Abstract 11565: Clinical Implications of Left Atrial Size and Its Changes After Cardiac Resynchronization Therapy in Patients With Heart Failure

Background: Little evidence is available regarding the impact of left atrial (LA) diameter, especially its changes after cardiac resynchronization therapy (CRT), on the prognosis of patients with heart failure (HF). Objective: To investigate the association of LA diameter and its changes with all-cause mortality and HF hospitalization in HF patients with CRT. Methods: This cohort study retrospectively included 488 HF patients with CRT, who were assessed with echocardiography at baseline and 6 months after CRT. The multivariate Cox proportional hazards regression models were used to examine the specific association of LA diameter and its changes with all-cause mortality and HF hospitalization. Results: Non-linear associations were found for LA diameter with all-cause mortality ( P = 0.006 for nonlinearity) and HF hospitalization ( P = 0.02 for nonlinearity). The positive association of LA diameter with all-cause mortality (HR, 1.88; 95% CI, 1.42-2.49) and HF hospitalization (HR, 1.72; 95% CI, 1.32-2.22) only in the range of LA diameter <45 mm. There was a positive association of LA diameter changes with all-cause mortality (HR, 1.29; 95% CI, 1.12-1.48) and HF hospitalization (HR, 1.28; 95% CI, 1.13-1.45). LA adverse remodeling (LAAR) was associated with an increased risk of all-cause mortality (HR, 2.35; 95% CI, 1.46-3.79) and HF hospitalization (HR, 2.18; 95% CI, 1.40-3.41). Conclusions: LA enlargement and LAAR were associated with an unfavorable outcome in HF patients with CRT. These findings suggest that monitoring LA diameter and its changes has potential clinical implications for HF treatment.

Role of radionuclide assessment of global and regional mechanical dyssynchrony of the heart in prognosis of cardiac resynchronization therapy in patients with heart failure

Aim. To determine the prognostic significance of cardiac regional mechanical dyssynchrony (MD), assessed by radionuclide equilibrium ventriculography (REVG) in candidates for cardiac resynchronization therapy (CRT).Material and methods. The study included 65 patients with indications for CRT according to current guidelines. Prior to CRT, all patients underwent REVG to assess cardiac contractile function and MD. According to the phase analysis, indicators of global and regional cardiac MD were evaluated: phase standard deviation (PSD), histogram band width (HBW), entropy, and interventricular dyssynchrony. The regional assessment included an evaluation of phase histograms obtained from the analysis of the contraction of certain walls: left ventricular (LV) anterior, lateral, posterior wall, right ventricular (RV) free wall, and the interventricular septum. To evaluate the effectiveness of treatment 6 months after CRT, all patients underwent echocardiography, on the basis of which patients were divided into groups of responders and non-responders.Results. REVG revealed significant differences in the initial regional MD values between the groups of responders and non-responders: in responders, MD values of RV free wall (PSD: 39 (28-67) vs 28 (20-50), p=0,03) and LV anterior wall (PSD: 28,5 (16-40) vs 14 (11-24), p=0,0005) were higher, and the LV lateral wall was lower (PSD: 10 (7-14) vs 15 (9-26), p=0,007) than in non-responders. Multivariate logistic regression found following independent predictors of a positive response to CRT: heart failure of ischemic origin, LV HBW, RV free wall PSD, anterior wall PSD, LV lateral wall HBW (p<0,001). The sensitivity and specificity of the model was 93% and 91%, respectively.Conclusion. Regional MD scintigraphy parameters increase the predictive value of REVG in CRT candidates. The most informative in this regard are the PSD of RV free wall and LV anterior wall, as well as the HBW of LV lateral wall.

Adaptive versus conventional cardiac resynchronisation therapy in patients with heart failure (AdaptResponse): a global, prospective, randomised controlled trial

Continuous automatic optimisation of cardiac resynchronisation therapy (CRT), stimulating only the left ventricle to fuse with intrinsic right bundle conduction (synchronised left ventricular stimulation), might offer better outcomes than conventional CRT in patients with heart failure, left bundle branch block, and normal atrioventricular conduction. This study aimed to compare clinical outcomes of adaptive CRT versus conventional CRT in patients with heart failure with intact atrioventricular conduction and left bundle branch block. This global, prospective, randomised controlled trial was done in 227 hospitals in 27 countries across Asia, Australia, Europe, and North America. Eligible patients were aged 18 years or older with class 2-4 heart failure, an ejection fraction of 35% or less, left bundle branch block with QRS duration of 140 ms or more (male patients) or 130 ms or more (female patients), and a baseline PR interval 200 ms or less. Patients were randomly assigned (1:1) via block permutation to adaptive CRT (an algorithm providing synchronised left ventricular stimulation) or conventional biventricular CRT using a device programmer. All patients received device programming but were masked until procedures were completed. Site staff were not masked to group assignment. The primary outcome was a composite of all-cause death or intervention for heart failure decompensation and was assessed in the intention-to-treat population. Safety events were collected and reported in the intention-to-treat population. This study is registered with ClinicalTrials.gov, NCT02205359, and is closed to accrual. Between Aug 5, 2014, and Jan 31, 2019, of 3797 patients enrolled, 3617 (95·3%) were randomly assigned (1810 to adaptive CRT and 1807 to conventional CRT). The futility boundary was crossed at the third interim analysis on June 23, 2022, when the decision was made to stop the trial early. 1568 (43·4%) of 3617 patients were female and 2049 (56·6%) were male. Median follow-up was 59·0 months (IQR 45-72). A primary outcome event occurred in 430 of 1810 patients (Kaplan-Meier occurrence rate 23·5% [95% CI 21·3-25·5] at 60 months) in the adaptive CRT group and in 470 of 1807 patients (25·7% [23·5-27·8] at 60 months) in the conventional CRT group (hazard ratio 0·89, 95% CI 0·78-1·01; p=0·077). System-related adverse events were reported in 452 (25·0%) of 1810 patients in the adaptive CRT group and 440 (24·3%) of 1807 patients in the conventional CRT group. Compared with conventional CRT, adaptive CRT did not significantly reduce the incidence of all-cause death or intervention for heart failure decompensation in the included population of patients with heart failure, left bundle branch block, and intact AV conduction. Death and heart failure decompensation rates were low with both CRT therapies, suggesting a greater response to CRT occurred in this population than in patients in previous trials. Medtronic.

Time-related factors predicting a positive response to cardiac resynchronisation therapy in patients with heart failure

This study aimed to identify time parameters predicting favourable CRT response. A total of 38 patients with ischemic cardiomyopathy, qualified for CRT implantation, were enrolled in the study. A 15% reduction in indexed end-systolic volume after 6 months was a criterion for a positive response to CRT. We evaluated QRS duration, measured from a standard ECG before and after CRT implantation and obtained from mapping with NOGA XP system (AEMM); and the delay, measured with the implanted device algorithm (DCD) and its change after 6 months (ΔDCD); and selected delay parameters between the left and right ventricles based on AEMM data. A total of 24 patients presented with a positive response to CRT versus 9 non-responders. After CRT implantation, we observed differences between responders and non-responders group in the reduction of QRS duration (31 ms vs. 16 ms), duration of paced QRS (123 ms vs. 142 ms), and the change of ΔDCDMaximum (4.9 ms vs. 0.44 ms) and ΔDCDMean (7.7 ms vs. 0.9 ms). The difference in selected parameters obtained during AEMM in both groups was related to interventricular delay (40.3 ms vs. 18.6 ms). Concerning local activation time and left ventricular activation time, we analysed the delays in individual left ventricular segments. Predominant activation delay of the posterior wall middle segment was associated with a better response to CRT. Some AEMM parameters, paced QRS time of less than 120 ms and reduction of QRS duration greater than 20 ms predict the response to CRT. ΔDCD is associated with favourable electrical and structural remodelling.Clinical trial registration: SUM No. KNW/0022/KB1/17/15.

PO-04-102 LOSS OF LEFT VENTRICULAR CAPTURE DURING ACUTE HEMOPERICARDIUM

Loss of left ventricular capture from a chronic quadripolar coronary sinus lead was observed during development of an iatrogenic cardiac pericardial effusion. Subsequently, during pericardiocentesis left ventricular capture was reobtained. Reaccumulation of hemopericardium again resulted in repeated observable loss of LV capture. No previous documentation in literature review is noted. This phenomenon may have critical clinical value in predicting significant pericardial effusion or affect the clinical value of cardiac resynchronization therapy in patients with chronic pericardial effusions. To demonstrate a previously undocumented clinical phenomenon that significantly affect patient care and outcomes. N/A We present a case of an 83 YO male patient with iatrogenic pericardial effusion during transseptal puncture resulting in cardiac tamponade and observed loss of left ventricular capture. Our patient presented for Watchman implantation however after transseptal puncture prior to Watchman implantation hemopericardium developed with cardiac tamponade. Loss of LV capture resulted in RV only pacing until pericardiocentesis with placement of a pericardial drain was placed. After evacuation of 80cc volume and gross reduction in pericardial effusion size on transesophageal echocardiography with resolution of cardiac tamponade, LV capture was again noted. Device interrogation revealed stable lead thresholds. During clinical followup, reaccumulation of hemopericardium again resulted in loss of LV capture prior to clinical tamponade and again resolution of pericardial effusion resulted in regaining biventricular capture. Figure 1: Progressive loss of biventricular capture is noted during pericardial effusion accumulation leading to cardiac tamponade. Hemopericardium may result in loss of left ventricular capture from a chronic coronary sinus lead with stable thresholds. The observed loss of capture occurred prior to clinical cardiac tamponade and may offer an early qualitative measure of significant pericardial effusions.

The Challenges of Cardiac Resynchronization Therapy in Patients with Dilated Cardiomyopathy and Persistent Left Superior Vena Cava: A Case Report and Concise Literature Review

Heart failure with reduced ejection fraction (HFrEF) is a chronic and debilitating disease, which requires extensive diagnostic and treatment resources in order to achieve an acceptable quality of life for the patient. While optimal medical treatment remains at the core of the disease's management, interventional cardiology also plays a very important role. However, in very rare situations, interventionists might find cases especially challenging due to the presence of venous anomalies, such as persistent left superior vena cava (PLSVC), anomalies that may go undiscovered during the patient's lifetime until venous cannulation is necessary. While these types of malformations also pose challenges in regards to standard pacemaker implantation, cardiac resynchronization (CRT) devices pose several additional challenges due to the complexity of the device and the necessity of finding an optimal position for the coronary sinus (CS) lead. We present the case of a 55-year-old male patient with advanced heart failure due to dilated cardiomyopathy (DCM) and LBBB who was a candidate for CRT-D therapy, describing the investigations that led to the discovery of the PLSVC as well as the technique and results of the intervention, while comparing our case to similar cases found in recent literature.

The therapeutic benefit of upgrade to cardiac resynchronization therapy in patients with pacing-induced cardiomyopathy

Pacing-induced cardiomyopathy (PICM) is an important cause of heart failure in patients with a right ventricular pacing burden. Recent evidence suggests that an upgrade to cardiac resynchronization therapy (CRT) may confer benefit in PICM. To assess the extent and identify predictors of improvement following upgrade to CRT in patients with PICM. We retrospectively analyzed 43 patients undergoing CRT upgrade for PICM over the 10-year period of 2011 to 2021 at our center. All patients with PICM who underwent device upgrade from a dual- or single-chamber ventricular pacemaker to CRT were included. PICM was defined as a decrease of ≥10% in left ventricular ejection fraction (LVEF), resulting in an LVEF <50% among patients with ≥20% Right ventricular pacing burden without an alternative cause for cardiomyopathy. LVEF significantly improved from 28.7% preupgrade to 44.3% post-CRT upgrade (P < .01). Of 37 patients with severe LV dysfunction, 34 (91.9%) improved to an LVEF >35% and 13 (35.1%) improved to an LVEF >50%. The LV end-diastolic diameter decreased from 5.9 cm preupgrade to 5.4 cm postupgrade (P < .01). Using linear regression, angiotensin-converting enzyme inhibitor or angiotensin receptor blocker use was associated with significant LVEF improvement (+7.21%, P = .05). We observed a low rate of complications, and 1 in 4 CRT upgrades required venoplasty (n = 10 of 43, 23.3%). We provide further evidence for the benefit of CRT upgrade in the management of patients with PICM.

Outcomes of conduction system pacing for cardiac resynchronization therapy in patients with heart failure: A multicenter experience

Whether conduction system pacing (CSP) is an alternative option for cardiac resynchronization therapy (CRT) in patients with heart failure remains an area of active investigation. The purpose of this study was to assess the echocardiographic and clinical outcomes of CSP compared to biventricular pacing (BiVP). This multicenter retrospective study included patients who fulfilled CRT indications and received CSP. Patients with CSP were matched using propensity score matching and compared in a 1:1 ratio to patients who received BiVP. Echocardiographic and clinical outcomes were assessed. Response to CRT was defined as an absolute increase of ≥5% in left ventricular ejection fraction (LVEF) at 6 months post-CRT. A total of 238 patients were included. Mean age was 69.8 ± 12.5 years, and 66 (27.7%) were female. Sixty-nine patients (29%) had His-bundle pacing, 50 (21%) had left bundle branch area pacing, and 119 (50%) had BiVP. Mean follow-up duration in the CSP and BiVP groups was 269 ± 202 days and 304 ± 262 days, respectively (P = .293). The proportion of CRT responders was greater in the CSP group than in the BiVP group (74% vs 60%, respectively; P = .042). On Kaplan-Meier analysis, there was no statistically significant difference in the time to first heart failure hospitalization (log-rank P = .78) and overall survival (log-rank P=.68) between the CSP and BiVP groups. In patients with heart failure and reduced ejection fraction, CSP resulted in greater improvement in LVEF compared to BiVP. Large-scale randomized trials are needed to validate these outcomes and further investigate the different options available for CSP.

Right ventricular cardiac resynchronization therapy in patients with right ventricular conduction delay and heart failure

Right ventricular cardiac resynchronization therapy in patients with right ventricular conduction delay and heart failure

PS-C24-10: HAEMODYNAMIC CHARACTERISTICS OF THE HEART BEFORE AND AFTER CRT IN PATIENTS WITH HEART FAILURE

The aim of the study: to evaluate the clinical and hemodynamic effects of resynchronization therapy in patients with congestive heart failure. Materials and Methods: seventy-six consecutive patients underwent echocardiography, NYHA classification, 6-minute walk test before and after cardiac resynchronization therapy. All had complete left bundle branch block, with a QRS complex duration greater than 130 ms. and left ventricular ejection fraction less than 35%. Also, all patients had received optimal medical therapy for at least 3 months before inclusion to the study. Results: we observed significant increase in left ventricular ejection fraction (on 35.4 ± 3.7%, p &lt; 0.001, compared with baseline) and decrease in end-systolic volume of the left ventricle (on 20.2 ± 3.0%, p &lt; 0.001 compared with baseline). Improvement in functional class of congestive heart failure by NYHA classification by more than 1 was observed in 68.4% of individuals, in 26.3% of participants demonstrated no change and 5.3% of patients had worsening of CHF symptoms. Conclusions: the response of patients with congestive heart failure to cardiac resynchronization therapy is heterogeneous. The relationship between left ventricular reverse remodeling and the functional class of the congestive heart failure was not significant.

The Effects of His Bundle Pacing Compared to Classic Resynchronization Therapy in Patients with Pacing-Induced Cardiomyopathy.

Pacing-induced cardiomyopathy (PICM) is among the most common right ventricular pacing complications. Upgrading to cardiac resynchronization therapy (CRT) is the recommended treatment option. Conduction system pacing with His bundle pacing (HBP) has the potential to restore synchronous ventricular activation and can be an alternative to biventricular pacing (BVP). Patients with PICM scheduled for a system upgrade to CRT were included in the prospective cohort study. Either HBP or BVP was used for CRT. Electrocardiographic, clinical, and echocardiographic measurements were recorded at baseline and six-month follow-up. HBP was successful in 44 of 53 patients (83%). Thirty-nine patients with HBP and 22 with BVP completed a 6-month follow-up. HBP led to a higher reduction in QRS duration than BVP, 118.3 ± 14.20 ms vs. 150.5 ± 18.64 ms, p < 0.0001. The improvement in New York Heart Association (NYHA) class by one or two was more common in patients with HBP than those with BiV (p = 0.04). Left ventricular ejection fraction (LVEF) improved in BVP patients from 32.9 ± 7.93% to 43.9 ± 8.07%, p < 0.0001, and in HBP patients from 34.9 ± 6.45% to 48.6 ± 7.73%, p < 0.0001. The improvement in LVEF was more considerable in HBP patients than in BVP patients, p = 0.019. The improvement in clinical outcomes and left ventricle reverse remodeling was more significant with HBP than BVP. HBP can be a valid alternative to BVP for upgrade procedures in PICM patients.

Different response criteria to cardiac resynchronization therapy in patients with congestive heart failure

Aim. To investigate the agreement among different response criteria to cardiac resynchronization therapy (CRT) and long-term mortality in patients with congestive heart failure (CHF).Methods. The study enrolled 141 patients (men 77.3%; women 22.7%) with CHF (65.2% ischemic and 34.8% non-ischemic etiology). Mean age was 58.6 [53.0;66.0] years. All patients had NYHA II-IV, left ventricular ejection fraction (LVEF) ≤35%; QRS ≥130 мs and/or left bundle branch block. Mean follow-up period was 45.0±34.2 months. Response to CRT was defined according to dynamics of NYHA functional class, LVEF, and left-ventricular end-systolic volume (LVESV).Results. Moderate agreement was found among LVEF and LVESV (Cohen’s k coefficient 0.591±0.068) while we did not find the agreement among echocardiographic criteria and NYHA. Long-term mortality had moderate negative correlation with LVESV (r=-0.486; pConclusion. Agreement between different criteria to define response to CRT is poor. The strongest correlation with long-term mortality was found for LVESV. This inconsistency among different response criteria severely limits the ability to generalize results over multiple CRT studies.

Systemic immune-inflammation index: A novel marker for predicting response to cardiac resynchronization therapy in patients with heart failure

Systemic immune-inflammation index: A novel marker for predicting response to cardiac resynchronization therapy in patients with heart failure

Structural and functional characteristics of the heart before and after CRT in patients with heart failure

The aim of the study was to evaluate the clinical and hemodynamic effects of resynchronization therapy in patients with congestive heart failure. Materials and methods: Seventy-six consecutive patients underwent echocardiography, NYHA classification, 6-minute walk test and clinical assessment scale modified by Mareev, before and after cardiac resynchronization therapy. All had complete left bundle branch block, with a QRS complex duration ≥ 130 ms. and left ventricular ejection fraction ≤ 35%. Also, all patients had received optimal medical therapy for at least 3 months before inclusion to the study. Results: We observed significant increase in left ventricular ejection fraction (35.4±3.7%, p < 0.001, compared with baseline) and decrease in end-systolic volume of the left ventricle (20.2 ±3.0 %, p < 0.001 compared with baseline). Improvement in functional class of congestive heart failure by NYHA classification by > 1 was observed in 68.4% of individuals, in 26.3% of participants demonstrated no change and 5.3% of patients had worsening of CHF symptoms. Conclusions: The response of patients with congestive heart failure to cardiac resynchronization therapy is heterogeneous. The relationship between left ventricular reverse remodeling and the functional class of the congestive heart failure was not significant. Key words: congestive heart failure, cardiac resynchronizing therapy, optimal drug therapy.

Evaluation of interventricular delay during cardiac resynchronization therapy in patients with quadripolar systems in long-term postoperative follow-up

Aim. To assess the association between changes in interventricular delay (IVD) and response to cardiac resynchronization therapy (CRT) during 24-month postoperative period in patients with quadripolar left ventricular leads.Material and methods. This retrospective non-randomized study included data from 48 patients with implanted CRT devices with quadripolar left ventricular (LV) leads, examined 3, 6, 12, 24 months after operation. CRT responders were considered patients with a decrease in end-systolic volume (ESV) by more than 10% compared with preoperative. To test the hypothesis about the rationale for choosing the maximum IVD when installing the LV lead, the group of patients was divided into two subgroups as follows: one with the maximum IVD (IVDmax, n=24), the other — without this condition (n=24).Results. A correlation was found between changes in IVD and ESV, as well as ejection fraction (EF) in the period of 6, 12 and 24 months after implantation compared to baseline. In the subgroup with IVDmax, the shortening of IVD in the postoperative period is higher at each considered period compared to the second subgroup, and in general, there is a more pronounced decrease in IVD over 24 months. At the same time, 3, 6, 12 months after surgery, patients with IVDmax show a significantly greater decrease in ESV and, accordingly, a greater increase in EF. Prognostic models of CRT response in the long term after implantation were created. Significant predictors were the initial IVD, changes in IVD in the early postoperative period and IVDmax selection. At the same time, not a single factor, taken separately, made it possible to separate responders and non-responders.Conclusion. A greater shortening of the IVD corresponds to a greater decrease in LV ESV and EDV, as well as a greater increase in EF in the long-term postoperative period. The choice of quadripolar LV lead in accordance with the maximum IVD is accompanied by a decrease in the proportion of non-responders, a more pronounced decrease in electrical ventricular dyssynchrony and an improvement in systolic function.