Outcome Of Cardiac Resynchronization Therapy Research Articles

Assessment of mechanical dyssynchrony can improve the new ESC-2021 guidelines for cardiac resynchronization therapy

Abstract Background In 2021, new guidelines for cardiac resynchronization therapy (CRT) were published by the European society of cardiology (ESC-2021), where the different classes of recommendations were based on a new ECG-based definition of left bundle branch block (LBBB). However, its association with reverse LV remodeling and additive prognostic value remain unknown. Aim To investigate (1) the association between the ESC-2021 CRT guidelines and reverse LV remodeling at follow up, and (2) the additive prognostic value of baseline assessment of mechanical dyssynchrony to the ESC-2021 guidelines. Methods We investigated 244 heart failure patients in sinus rhythm treated with CRT in two European centers. 70% of the population were males. Mean age was 69 ± 10 years, QRS duration: 154 ± 24 msec. Mechanical dyssynchrony at baseline was defined as the presence of apical rocking or septal flash (ApRock/SF) in 2D transthoracic echocardiography. LV volumes were measured at baseline and at 12 ± 6 months after CRT, where the amount of CRT induced reverse LV remodeling was calculated as the percent change of LVESV at follow-up compared to baseline. Results Applying the ESC-2021 LBBB definition, only 18% (n=45) of patients had LBBB. Applying the guidelines, only 14% (n=35) had class I recommendation (LBBB + QRS ≥ 150 msec), 44% (n=107) had class IIa (LBBB + QRS 130-149 msec or non-LBBB + QRS ≥ 150 msec), 29% (n=70) had class IIb (Non-LBBB + QRS 130-149 msec), and 13% (n = 33) were not recommended according to the ESC-2021 because of having baseline QRS duration between 120 and 129 msec. On the other hand, ApRock/SF was evident in 57% (n=140) of the patients. There was non-significant difference in the relative decrease in LVESV at follow up between patients with LBBB and non-LBBB applying the new LBBB definition (44% [IQR: 32-63], vs. 39%, IQR [20-57], P = 0.08, panel A). Similarly, there was no significant difference in the relative decrease in LVESV at CRT follow up among the four guideline recommendation classes, panel B. We combined presence of mechanical asynchrony at baseline with each of the guideline recommendation classes. The combination of ApRock/SF with classes IIa and IIb improved the prediction of reverse LV remodeling significantly (P<0.001 and <0.01 respectively), while adding mechanical asynchrony did not significantly improve prediction in the class I and the not-recommended subgroups. However, results of these last 2 may have been impacted by a small number of patients, panel C. Conclusion The new ESC-2021 definition of LBBB is associated with few patients with LBBB and consequently small number of patients with class I recommendation according to the new guidelines. There was weak association between the new ESC-2021 guideline classes of recommendation and reverse LV remodeling after CRT. However, baseline assessment of ApRock and SF can significantly improve the guidelines in predicting CRT outcome.

Clinical and Electrocardiographic Predictors of Cardiac Resynchronization Therapy Response That Correlate with the 6 min Walking Test.

Background: Cardiac resynchronization therapy is an essential treatment for heart failure patients. Candidates typically have cardiomyopathy accompanied by delayed electrical activation in the left ventricular lateral wall, causing uncoordinated contractions and worsening heart failure. Heart failure severity can be assessed with functional tests: the cardiopulmonary test, which is a maximal exercise test, remains the gold standard, but the 6 min walk test has emerged as an easier, faster, and more comfortable alternative to be used by clinicians to adjust treatment protocols for cardiovascular and pulmonary conditions. Methods: This is a prospective observational study that included 69 patients from a single healthcare facility, and the purpose was to determine if the 6 min walk test results could be associated with changes in various electrocardiographic, clinical, functional, and demographic parameters. All the parameters and the 6 min walk distance were recorded at four key time moments: before the procedure and after 6, 9, and 12 months. The electrocardiographic parameters were obtained from the patients' electrocardiograms recorded in the four key moments and included variables such as QRS area, duration, percentage of biventricular pacing, and many others, while the functional variables included the monitored intraprocedural systolic blood pressure and the end-systolic left ventricular volume. We also aimed to check if clinical conditions such as diabetes and chronic kidney disease and demographic variables such as age or sex have any impact. Results and Conclusions: All this research was performed in order to identify which parameters hold a predictive value and can serve as future criteria for better patient selection and for defining a proper resynchronization outcome. The study shows that parameters such as diabetes and QRS duration have an impact over the 6 min walk distance. Also, newer variables such as the QRS area and the R/S ratio may represent a direction worth studying in order to predict the outcomes of cardiac resynchronization therapy.

Outcomes of cardiac resynchronization therapy (CRT) in cardiac sarcoidosis patients with a range of ejection fractions.

In cardiac sarcoidosis (CS) patients, the benefit of cardiac resynchronization therapy (CRT) remains unclear. We sought to assess the short-term and long-term effects of CRT in CS patients with a range of left ventricular (LV) ejection fractions (LVEFs). Consecutive CS patients with heart failure with reduced ejection fraction (HFrEF; LVEF≤40%), mildly reduced ejection fraction (HFmrEF; LVEF 41%-49%) and preserved ejection fraction (HFpEF; LVEF≥50) treated with CRT under the care of a tertiary UK centre between 2008 and 2023 were reviewed. CRT response was defined by >5% improvement in serial LVEF. The primary endpoint was a composite of all-cause mortality, cardiac transplantation or unplanned hospitalization for decompensated heart failure. The secondary endpoint included ventricular arrhythmic events. Of the 100 patients enrolled (age 58±10years; 71% male), 63 had HFrEF, 17 had HFmrEF and 20 had HFpEF. After short-term follow-up (9.8±5.4months), HFrEF patients demonstrated significant LVEF response (P<0.01). On Kaplan-Meier analysis (follow-up 38±32months), HFrEF non-responders had significantly worse event-free survival compared with HFrEF responders for the primary (P<0.001) and secondary (P=0.001) endpoints. Despite short-term LV function improvement, CRT responders still had worse event-free survival compared with HFmrEF/HFpEF patients for the primary endpoint (P<0.001). On multivariable Cox analysis, age [hazard ratio (HR) 1.05, 95% confidence interval (CI) 1.01-1.10, P=0.008] and HFrEF CRT non-response (HR 12.33, 95% CI 2.45-61.87, P=0.002) were associated with the primary endpoint. In CS patients with HFrEF, CRT response is associated with a better long-term prognosis than non-response. However, HFrEF CRT responders still have worse long-term prognosis than HFmrEF/HFpEF patients.

Vitamin D as a predictor of clinical response among patients with cardiac resynchronization therapy (CRT).

Cardiovascular and noncardiovascular comorbidities have been recognized as predictors of clinical response in patients receiving cardiac resynchronization therapy (CRT). However, data on vitamin D as a predictor of CRT response are conflicting. We identified studies from MEDLINE and Embase databases, searching from inception to May 2024, to investigate the association between 25-OH vitamin D levels before CRT implantation and outcomes. Studies had to report 25-OH vitamin D levels or the proportion of patients with vitamin D insufficiency and categorize outcomes as CRT responders or nonresponders. We extracted mean 25-OH vitamin D and standard deviations for both groups from each study and calculated the pooled mean difference (MD). We also retrieved risk ratios, and 95% confidence intervals (CIs) for the association between vitamin D insufficiency and lack of CRT response, combining them using the generic inverse variance method. Our meta-analysis included four studies. CRT responders had higher levels of 25-OH vitamin D than nonresponders, with a pooled MD of 8.04 ng/mL (95% CI: 3.16-12.93; I 2 = 48%, p < .001). Patients with vitamin D insufficiency before implantation had higher odds of lacking response to CRT, with a pooled RR of 3.28 (95% CI: 1.43-7.50; I 2 = 0%, p = .005) compared to those with normal vitamin D. CRT responders had higher 25-OH vitamin D levels compared to nonresponders. Vitamin D insufficiency was associated with a higher risk of nonresponse to CRT. These findings highlight the importance of monitoring and managing vitamin D levels in these patients.

Association Between use of an Adaptive Cardiac Resynchronization Therapy Algorithm and Healthcare Utilization and Cost

To assess the association between use of adaptive pacing on clinical and economic outcomes of CRT recipients in a real-world analysis. The AdaptivCRTTM algorithm was shown in prior subgroup analyses of prospective trials to achieve clinical benefits, but a large prospective trial showed nonsignificant changes in the endpoint of mortality or heart failure hospitalizations. CRT-implanted patients from the Optum Clinformatics® database with ≥90 days of follow-up were included. Remote monitoring data was used to classify patients based on CRT setting - adaptive biventricular and left ventricular pacing (aCRT) vs. standard biventricular pacing (Standard CRT). Inverse probability of treatment weighting was used to adjust for baseline differences between groups. Mortality, 30-day readmissions, healthcare utilization, and payer and patient costs were evaluated post-implantation. This study included 2,412 aCRT and 1,638 Standard CRT patients (mean follow-up: 2.4 ± 1.4 years), with balanced baseline characteristics after adjustment. The aCRT group was associated with lower all-cause mortality (adjusted hazard ratio = 0.88 [95% confidence interval (CI):0.80, 0.96]), fewer all-cause 30-day readmissions (adjusted incidence rate ratio = 0.87 [CI:0.81, 0.94]), and fewer all-cause and HF-related inpatient, outpatient, and emergency department (ED) visits. The aCRT cohort was also associated with lower all-cause outpatient payer-paid amounts and lower all-cause and HF-related inpatient and ED patient-paid amounts. In this retrospective analysis of a large real-world cohort, use of an adaptive CRT algorithm was associated with lower mortality, reduced healthcare resource utilization, and lower payer and patient costs. While cardiac resynchronization therapy (CRT) improves quality of life and clinical outcomes for certain heart failure patients, some patients do not respond to this therapy. Adaptive CRT algorithms (aCRT), such as AdaptivCRTTM, have been developed with the goal of improving effectiveness of CRT, and consequently, clinical and economic outcomes. This research study used a large database of administrative claims data - which contains information on patient demographics, diagnoses, healthcare services received, mortality, and cost data - to compare clinical and economic outcomes between CRT patients with the aCRT algorithm turned on (aCRT group) and CRT patients with the aCRT algorithm turned off (standard CRT group). Statistical methods were used to adjust for baseline differences between the aCRT group and standard CRT groups. Ultimately, the aCRT group was found to have a lower risk of all-cause mortality, fewer all-cause 30-day readmissions, fewer hospital visits (including inpatient, outpatient, and emergency department visits), and lower costs to payers and patients for specific types of costs.

Speckle Tracking Echocardiography in Patients with Non-Ischemic Dilated Cardiomyopathy Who Undergo Cardiac Resynchronization Therapy: A Narrative Review.

Non-ischemic dilated cardiomyopathy (DCM) represents a significant cause of heart failure, defined as the presence of left ventricular (LV) dilatation and systolic dysfunction unexplained solely by abnormal loading conditions or coronary artery disease. Cardiac resynchronization therapy (CRT) has emerged as a cornerstone in the management of heart failure, particularly in patients with DCM. However, identifying patients who will benefit the most from CRT remains challenging. Speckle tracking echocardiography (STE) has garnered attention as a non-invasive imaging modality that allows for the quantitative assessment of myocardial mechanics, offering insights into LV function beyond traditional echocardiographic parameters. This comprehensive review explores the role of STE in guiding patient selection and optimizing outcomes in CRT for DCM. By assessing parameters such as LV strain, strain rate, and dyssynchrony, STE enables a more precise evaluation of myocardial function and mechanical dyssynchrony, aiding in the identification of patients who are most likely to benefit from CRT. Furthermore, STE provides valuable prognostic information and facilitates post-CRT optimization by guiding lead placement and assessing response to therapy. Through an integration of STE with CRT, clinicians can enhance patient selection, improve procedural success rates, and ultimately, optimize clinical outcomes in patients with DCM. This review underscores the pivotal role of STE in advancing personalized management strategies for DCM patients undergoing CRT.

Predicting the response to cardiac resynchronization therapy using in silico heart models: pilot study of comparison between in silico and real cardiac resynchronization therapy outcomes

Abstract Background Cardiac resynchronization therapy (CRT) is treatment for patients with heart failure and left ventricular (LV) dyssynchrony. The objective of this study is to evaluate the feasibility of an in silico electromechanical heart model to predict CRT outcomes. Methods The three-dimensional heart geometries of 11 patients (age, 64.0±10.7 years, 4 men) with CRT were constructed from cardiac computed tomography images. We coupled cardiac electrical excitation and mechanical contraction with vascular hemodynamics using a lumped parameter model. We predicted the LV end-diastolic and end-systolic volumes and LV ejection fraction (LVEF) after CRT implantation using the in silico CRT simulation model. We compared the in silico CRT outcomes with the real CRT outcomes. Results Two patients were in silico CRT responders, and those 2 patients were also real CRT responders. Nine patients were in silico CRT non-responders, 8 who were real CRT non-responders, and 1 who was a real CRT responder. The in silico CRT outcomes agreed with the real CRT outcomes in 10 of 11 patients. The positive and negative predictive values and accuracy of the in silico CRT model were 100%, 88.9%, and 90.9%, respectively. Conclusion The in silico CRT simulation model is feasible for predicting real CRT outcomes.In silico CRT simulation model generatioAn example (patient No. 2) of LV (black

Association between amount of biventricular pacing and heart failure status measured by a multisensor implantable defibrillator algorithm

Abstract Background Achieving a high biventricular pacing percentage (BiV%) is crucial for optimizing outcomes in cardiac resynchronization therapy (CRT). The HeartLogic index, a multiparametric heart failure (HF) risk score, incorporates implantable defibrillator (ICD)-measured variables and has demonstrated its predictive ability for impending HF decompensation. Purpose This study aimed to investigate the relationship between daily BiV% in CRT ICD patients and their HF status, assessed using the HeartLogic algorithm. Methods The HeartLogic algorithm was activated in 306 patients across 26 centers, with a median follow-up of 26 months (25th–75th percentile: 15-37). Results During the follow-up period, 619 HeartLogic alerts were recorded in 186 patients. Overall, daily values associated with the best clinical status (highest first heart sound, intrathoracic impedance, patient activity; lowest combined index, third heart sound, respiration rate, night heart rate) were associated with a BiV% exceeding 99%. We identified 455 instances of BiV% dropping below 98% after consistent pacing periods. Longer episodes of reduced BiV% (hazard ratio: 2.68; 95% CI: 1.02-9.72; P=0.045) and lower BiV% (hazard ratio: 3.97; 95% CI: 1.74-9.06; P=0.001) were linked to a higher risk of HeartLogic alerts. BiV% drops exceeding 7 days predicted alerts with 90% sensitivity (95% CI [74%-98%]) and 55% specificity (95% CI [51%-60%]), while BiV% ≤96% predicted alerts with 74% sensitivity (95% CI [55%-88%]) and 81% specificity (95% CI [77%-85%]). Conclusions A clear correlation was observed between reduced daily BiV% and worsening clinical conditions, as indicated by the HeartLogic index. Importantly, even minor reductions in pacing percentage and duration were associated with an increased risk of HF alerts.Time to event

Absence of late gadolinium enhancement and outcomes of cardiac resynchronization therapy in non-ischemic dilated cardiomyopathy

Abstract Background Among patients with non-ischemic dilated cardiomyopathy (DCM) with indication for cardiac resynchronization therapy (CRT), there are no clear recommendations about who should receive a CRT-defibrillator (CRT-D) and who should have CRT-pacemaker (CRT-P). Absence of late gadolinium enhancement (LGE) at cardiac magnetic resonance (CMR) has a high negative predictive value for ventricular arrhythmias (VA) and sudden death (SD) in DCM and is a predictor of reverse remodelling in several scenarios. Purpose To evaluate the association between absence of LGE and VA/SD or echocardiographic response to CRT in DCM patients treated with CRT. Methods Multicenter retrospective observational cohort study including consecutive DCM patients with de-novo CRT implant and with available CMR. The primary endpoints were: 1) a combined arrhythmic endpoint including appropriate defibrillator therapies, sustained VA and sudden death. 2) echocardiographic response to CRT, intended as an increase ≥10% in left ventricular ejection fraction (LVEF). Results We included 167 patients, 55% males, with median QRS duration of 160ms and median LVEF of 25%. LGE was present in 46% of cases (LGE+). A CRT-D was implanted in 73% of patients. Median follow-up was 63 months. Of note, among patients without LGE (LGE-) we did not record any event of the combined arrhythmic endpoint. The cumulative incidence of the arrhythmic endpoint was significantly higher in LGE+ than in LGE- patients (25% vs 0%, p&amp;lt;0.001) and LGE was an independent predictor of this endpoint (adjusted HR 42, p&amp;lt;0.001). The proportion of responders to CRT was significantly higher in LGE- than in LGE+ cases (81% vs 53%, p&amp;lt;0.001); absence of LGE was the strongest predictor of echocardiographic response to CRT at multivariate analysis (adjusted OR 4.1, p=0.001). Super-responders (i.e. those with LVEF≥50% at follow-up) were also more frequent among LGE- than LGE+ patients (46% vs 21%, p=0.001) and absence of LGE was an independent predictor of LVEF normalization (HR 2.6, p=0.03). Conclusions Among DCM patients who receive CRT, those without LGE have an extremely low (or null in this case) arrhythmic risk and, at the same time, they have a high probability of echocardiographic response to CRT. Thus, LGE- patients could be ideal candidates for CRT-P instead of CRT-D.

Effectiveness of dynamic atrioventricular optimization during patient exercise in cardiac resynchronization therapy

Abstract Background Cardiac resynchronization therapy (CRT) is considered the standard treatment for patients with heart failure and prolonged QRS duration. Recent studies suggest that atrioventricular delay (AVD) optimization can play a key role in QRS narrowing, thus improving CRT outcomes. For this purpose, device-based algorithms have been developed. In particular, the SyncAV algorithm continuously monitors the patient’s intrinsic AVD and dynamically adjusts the pacing AVD to allow fusion of the left ventricle pacing with intrinsic right ventricle depolarization. SyncAV optimization is usually performed in a single patient condition, i.e. at rest, and in a single operating scenario of the device, i.e. during atrial sensing. Purpose This study aims to compare QRS narrowing after AVD optimization using SyncAV in CRT-treated patients at rest, during moderate exertion, and during an increase in the atrial pacing rate. Methods This is a prospective, non-randomized, non-blinded, multicenter study. The study population consisted of patients in sinus rhythm, PR interval &amp;lt; 350 ms, and rest ventricular rate &amp;lt; 100 bpm. Within one month from the implant, patients were assessed for AVD optimization with SyncAV, selecting the offset (i.e. 10 to 40% AVD) that resulted in the shortest QRS duration (QRSd). Subsequently, patients performed moderate physical activity using a bicycle ergo-meter while a surface ECG was collected. QRSd was assessed once patients achieved a heart rate over 20 bpm to baseline heart rate, up to 100 bpm. Finally, QRSd narrowing was evaluated during a programmed increase in atrial pacing (i.e. &amp;gt;20 bpm of baseline atrial rate). Results Nine patients were treated with CRT and enrolled (age 67,3 ± 13,2 years; 66% male; LV ejection fraction 33,7±2,9 %; intrinsic QRSd 155,6 ± 12,7 ms) with intact atrioventricular conduction (PR interval 170,6±25,8 ms). The median SyncAV offset that provided the best QRSd reduction was 20 % (10 - 35%). Intrinsic QRSd was reduced to 132,7 ± 10,0 ms (-14,2±9,4%) with standard biventricular pacing and to 122,0 ± 11,2 ms (-21,2±8,5%) with SyncAV optimization. During exercise the mean heart rate was 88,1 bpm, the QRSd was reduced to 132,7 ± 10,0 ms (-14,2±9,4%) with standard biventricular pacing and to 124,9 ± 14,9 ms (-19,3±10,8 %) with SyncAV optimization. The mean heart rate during atrial pacing was 90 bpm with paced QRSd of 126,0 ±13,9 ms (-18,9±7,3% from baseline) with SyncAV optimization and paced PR interval of 198,2±22,7ms. Conclusion We evaluated the effectiveness of SyncAV for AVD optimization in out-of-clinic. This study demonstrates the possibility of narrowing the QRSd using SyncAV at several activity levels. Nevertheless, a deeper evaluation is needed to confirm our findings, investigating the SyncAV role in a larger population of patients.

Cardiac resynchronization therapy for patients with mild to moderately reduced ejection fraction and left bundle branch block

BackgroundIt is unknown whether cardiac resynchronization therapy (CRT) would improve or halt the progression of heart failure (HF) in patients with mild to moderately reduced ejection fraction (HFmmrEF) and left bundle branch block (LBBB). ObjectiveThis study aimed to investigate the outcomes of CRT in patients with HFmmrEF and left ventricular conduction delay. MethodsA prospective, randomized clinical trial sponsored by the National Heart, Lung, and Blood Institute included 76 patients who met the study inclusion criteria (left ventricular ejection fraction [LVEF] of 36%–50% and LBBB). Patients received CRT-pacemaker and were randomized to CRT-OFF (right ventricular pacing 40 beats/min) or CRT-ON (biventricular pacing 60–150 beats/min). At a 6-month follow-up, pacing programming was changed to the opposite settings. New York Heart Association class, N-terminal pro–brain natriuretic peptide levels, and echocardiographic variables were collected at baseline, 6 months, and 12 months. The primary study end point was the left ventricular end-systolic volume (LVESV) change from baseline, and the primary randomized comparison was the comparison of 6-month to 12-month changes between randomized groups. ResultsThe mean age of the patients was 68.4 ± 9.8 years (male, 71%). Baseline characteristics were similar between the 2 randomized groups (all P > .05). In patients randomized to CRT-OFF first, then CRT-ON, LVESV was reduced from baseline only after CRT-ON (baseline, 116.1 ± 36.5 mL; CRT-ON, 87.6 ± 26.0 mL; P < .0001). The randomized analysis of LVEF showed a significantly better change from 6 to 12 months in the OFF-ON group (P = .003). LVEF was improved by CRT (baseline, 41.3% ±.7%; CRT-ON, 46.0% ± 8.0%; P = .002). In patients randomized to CRT-ON first, then CRT-OFF, LVESV was reduced after both CRT-ON and CRT-OFF (baseline, 109.8 ± 23.5 mL; CRT-ON, 91.7 ± 30.5 mL [P < .0001]; CRT-OFF, 99.3 ± 28.9 mL [P = .012]). However, the LVESV reduction effect became smaller between CRT-ON and CRT-OFF (P = .027). LVEF improved after both CRT-ON and CRT-OFF (baseline, 42.7% ± 4.3%; CRT-ON, 48.5% ± 8.6% [P < .001]; CRT-OFF, 45.9% ± 7.7% [P = .025]). ConclusionCRT for patients with HFmmrEF significantly improves LVEF and ventricular remodeling after 6 months of CRT. The study provides novel evidence that early CRT benefits patients with HFmmrEF with LBBB.

Interaction of left ventricular size with the outcome of cardiac resynchronization therapy in Japanese patients.

We analyzed the influence of the QRS duration (QRSd) to LV end-diastolic volume (LVEDV) ratio on cardiac resynchronization therapy (CRT) outcomes in heart failure patients classified as III/IV per the New York Heart Association (NYHA) and with small body size. We proposed the hypothesis that the QRSd/LV size ratio is a better index of the CRT substrate. We enrolled 114 patients with advanced heart failure (NYHA class III/IV, and LV ejection fraction >35%) who received a CRT device, including those with left bundle branch block (LBBB) and QRSd ≥120 milliseconds (n = 60), non-LBBB and QRSd ≥150 milliseconds (n = 30) and non-LBBB and QRSd of 120-149 milliseconds (n = 24). Over a mean follow-up period of 65 ± 58 months, the incidence of the primary endpoint, a composite of all-cause death and hospitalization for heart failure, showed no significant intergroup difference (43.3% vs. 50.0% vs. 37.5%, respectively, p = .72). Similarly, among 104 patients with QRSd/LVEDV ≥ 0.67 (n = 54) and QRSd/LVEDV < 0.67 (n = 52), no significant differences were observed in the incidence of the primary endpoint (35.1% vs. 51.9%, p = .49). Nevertheless, patients with QRSd/LVEDV ≥ 0.67 showed better survival than those with QRSd/LVEDV < 0.67 (14.8% vs. 34.6%, p = .0024). Advanced HF patients with a higher QRSd/LVEDV ratio showed better survival in this small-body-size population. Thus, the risk is concentrated among those with a larger QRSd, and patients with a relatively smaller left ventricular size appeared to benefit from CRT.

Association between amount of biventricular pacing and heart failure status measured by a multisensor implantable defibrillator algorithm

Achieving a high biventricular pacing percentage (BiV%) is crucial for optimizing outcomes in cardiac resynchronization therapy (CRT). The HeartLogic index, a multiparametric heart failure (HF) risk score, incorporates implantable cardioverter-defibrillator (ICD)-measured variables and has demonstrated its predictive ability for impending HF decompensation. This study aimed to investigate the relationship between daily BiV% in CRT ICD patients and their HF status, assessed using the HeartLogic algorithm. The HeartLogic algorithm was activated in 306 patients across 26 centers, with a median follow-up of 26 months (25th-75th percentile: 15-37). During the follow-up period, 619 HeartLogic alerts were recorded in 186 patients. Overall, daily values associated with the best clinical status (highest first heart sound, intrathoracic impedance, patient activity; lowest combined index, third heart sound, respiration rate, night heart rate) were associated with a BiV% exceeding 99%. We identified 455 instances of BiV% dropping below 98% after consistent pacing periods. Longer episodes of reduced BiV% (hazard ratio: 2.68; 95% CI: 1.02-9.72; P = .045) and lower BiV% (hazard ratio: 3.97; 95% CI: 1.74-9.06; P=.001) were linked to a higher risk of HeartLogic alerts. BiV% drops exceeding 7 days predicted alerts with 90% sensitivity (95% CI [74%-98%]) and 55% specificity (95% CI [51%-60%]), while BiV% ≤96% predicted alerts with 74% sensitivity (95% CI [55%-88%]) and 81% specificity (95% CI [77%-85%]). A clear correlation was observed between reduced daily BiV% and worsening clinical conditions, as indicated by the HeartLogic index. Importantly, even minor reductions in pacing percentage and duration were associated with an increased risk of HF alerts.

CMR feature tracking–based left atrial mechanics predicts response to cardiac resynchronization therapy and adverse outcomes

BackgroundCardiac resynchronization therapy (CRT) is an established therapy for advanced heart failure (HF) with prolonged QRS duration. However, 30% of patients have shown no benefit from the treatment. ObjectiveThis study aimed to examine the value of left atrial (LA) mechanics by cardiac magnetic resonance (CMR) to predict response to CRT and clinical outcomes. MethodsA total of 163 CRT recipients with preimplantation CMR examination were retrospectively recruited. CMR feature tracking was used to evaluate LA size and function. The end points include (1) improvement of at least 5% in left ventricular ejection fraction combined with a reduction of at least 1 New York Heart Association functional class at 6-month follow-up and (2) any all-cause death or HF hospitalization during follow-up. ResultsOverall, 82 (50.3%) were CRT responders. CRT nonresponders had larger LA and worse LA reservoir and booster pump function than did responders (P < .001 for all). LA structural (maximum volume index < 47 mL/m2) and functional (booster pump strain > 8.5%) criteria were incremental to traditional indicators in detecting CRT response (χ2, 40.83 vs 9.98; P < .001). During follow-up (median 41 months), survival free from death or HF hospitalization increased with the number of positive LA criteria (log-rank, P < .001). After adjustment for clinical confounders, the absence of the 2 criteria remained associated with a considerably increased risk of death or HF hospitalization (adjusted hazard ratio 6.2; 95% confidence interval 2.15–17.88; P = .001). ConclusionThe preprocedure LA mechanics evaluated using CMR may be useful to predict response to CRT and improve risk stratification in CRT recipients.

Is CRT Optimization Obsolete? A Referral Center's Experience.

Cardiac resynchronization therapy (CRT) is a well-established therapy for patients with heart failure (HF). However, 30% of HF patients do not show any improvement in clinical status after CRT implantation. In this study, we report our echocardiography-based CRT optimization methodology, in daily practice at our CRT referral center. We included 350 ambulatory patients, who were referred to our center for optimization after CRT implantation. A protocol-driven echocardiographic approach for adjusting mechanical dyssynchrony, whereby adjusting for ventriculoventricular (VV) delays with strain and atrioventricular (AV) delays with Doppler echocardiography was performed. We defined changes in left ventricular ejection fraction (LVEF) and New York Heart Association (NYHA) classes as outcome variables in the evaluation of the CRT outcomes. Optimization was obtained in 288 (82%) patients. VV and AV timings were adjusted to 61% and 51%, respectively. In 3%, biventricular pacing was turned off and in 3% left ventricular (LV) only pacing was programmed. The LVEF and NYHA class showed significant improvements in all patients who underwent CRT optimization. CRT optimization remains valuable in improving LVEF and functional status measured using the NYHA class in all patients receiving CRT devices.

Clinical characteristics and outcome of cardiac resynchronization therapy for heart failure in National Hospital of Sri Lanka from year 2005 to 2020 – a retrospective observational study

BackgroundCardiac resynchronization therapy (CRT) has been a well-established treatment modality for moderate to severe left ventricular systolic dysfunction with left ventricular desynchrony. This is the pioneering study that analyses the cohort who underwent CRT implantation at the National Hospital of Sri Lanka (NHSL) in Colombo from 2005 to 2020.ObjectivesThis study was carried out to describe socio-demographic factors, improvements in clinical outcome (symptoms, electrocardiographic, and echocardiographic features), and post-CRT complications in the study population, as well as to determine the efficacy of CRT in heart failure.MethodA retrospective observational study was conducted on all the living patients who had undergone CRT implantation from 2005 to 2020. The data was gathered from all the consented patients who visited the device programming clinic using a physician-administered questionnaire and clinical records. Data was analyzed using SPSS 25, and significant statistics were assessed with the McNemer test, the Student T test, and the Chi-Squared test.ResultsThe study included 50 patients with a mean age of 52.82+/− 11.66 years and female predominance (56%, n = 28). Idiopathic dilated cardiomyopathy (50%, n = 25) was the leading etiological factor, followed by ischemic cardiomyopathy (28%, n = 14). Clinical symptoms have improved significantly with CRT implantation (p < 0.001). A significant improvement was found in NYHA functional class (p < 0.001, 95% CI = 0.072 to 0.284), QRS width (p < 0.001, 95% CI = 0.229 to 0.534), ejection fraction (p < 0.001, 95% CI = − 16.437 to − 8.504), and LV EDD (p < 0.001, 95% CI = 2.89 to 9.24). Post-CRT complications included lead malfunction (6%, n = 3) and chronic (14%, n = 7), bleeding or hematoma (2%, n = 1), pocket erosion or infection (6%, n = 3), and infective endocarditis (2%, n = 1).ConclusionAccording to the study, CRT significantly improves both clinical and functional outcomes in patients with moderate to severe heart failure.

The Year in Hungarian Cardiology 2023: Arrhythmias

In 2023, Hungary produced notable scientific publications focused on cardiac arrhythmias. This review highlights the most impactful papers, authored at least in part by Hungarians, featuring work conducted at Hungarian research sites and published in international peer-reviewed journals. We give a short overview regarding papers dealing with the role of imaging (different types of ultrasound, cardiac magnetic resonance imaging and electroanatomical mapping) in treating cardiac arrhythmias. We summarize the novelties of ischemic complications of atrial fibrillation (AF), cerebral safety of AF ablation, and current AF ablation techniques. Optimizing risk stratification of ventricular tachycardia (VT) ablation was a landmark paper of our “machine learning” research. Further studies have made significant strides in cardiac device therapy, notably through the groundbreaking BUDAPEST-CRT Upgrade Trial for heart failure, which demonstrated marked reductions in deaths and hospitalizations following Cardiac Resynchronization Therapy (CRT) upgrade procedures. Research on the impact of frailty on CRT outcomes has underscored the importance of tailored treatments. Artificial intelligence, particularly topological data analysis, has been crucial in personalizing CRT therapy. Additionally, advancements in remote monitoring and lead extraction techniques have mirrored the rapid evolution of cardiac technology and care.

Kiosk 4R-TC-03 - CMR Feature Tracking-based Left Atrial Mechanics Predicts Response to Cardiac Resynchronization Therapy and Adverse Outcomes

Kiosk 4R-TC-03 - CMR Feature Tracking-based Left Atrial Mechanics Predicts Response to Cardiac Resynchronization Therapy and Adverse Outcomes

Using artificial intelligence-enabled electrocardiogram to predict cardiac resynchronization therapy outcomes of left bundle branch area pacing.

Using artificial intelligence-enabled electrocardiogram to predict cardiac resynchronization therapy outcomes of left bundle branch area pacing.

Association of vectorcardiographic T-wave area with clinical and echocardiographic outcomes in cardiac resynchronization therapy.

Data on repolarization parameters in cardiac resynchronization therapy (CRT) are scarce. We investigated the association of baseline T-wave area, with both clinical and echocardiographic outcomes of CRT in a large, multi-centre cohort of CRT recipients. Also, we evaluated the association between the baseline T-wave area and QRS area. In this retrospective study, 1355 consecutive CRT recipients were evaluated. Pre-implantation T-wave and QRS area were calculated from vectorcardiograms. Echocardiographic response was defined as a reduction of ≥15% in left ventricular end-systolic volume between 3 and 12 months after implantation. The clinical outcome was a combination of all-cause mortality, heart transplantation, and left ventricular assist device implantation. Left ventricular end-systolic volume reduction was largest in patients with QRS area ≥ 109 μVs and T-wave area ≥ 66 μVs compared with QRS area ≥ 109 μVs and T-wave area < 66 μVs (P = 0.004), QRS area < 109 μVs and T-wave area ≥ 66 μVs (P < 0.001) and QRS area < 109 μVs and T-wave area < 66 μVs (P < 0.001). Event-free survival rate was higher in the subgroup of patients with QRS area ≥ 109 μVs and T-wave area ≥ 66 μVs (n = 616, P < 0.001) and QRS area ≥ 109 μVs and T-wave area < 66 μVs (n = 100, P < 0.001) than the other subgroups. In the multivariate analysis, T-wave area remained associated with echocardiographic response (P = 0.008), but not with the clinical outcome (P = 0.143), when QRS area was included in the model. Baseline T-wave area has a significant association with both clinical and echocardiographic outcomes after CRT. The association of T-wave area with echocardiographic response is independent from QRS area; the association with clinical outcome, however, is not.