Outcomes of Mitral Valve Regurgitation Management after Expert Multidisciplinary Valve Team Evaluation.

Background/Objectives: Mitral regurgitation (MR) affects millions worldwide, necessitating timely intervention. There are significant clinical challenges in the conservative management of MR, leaving a knowledge gap regarding the impact of multidisciplinary decision-making on treatment outcomes. This study aimed to provide insights into the impact of multidisciplinary decision-making on the survival outcomes of MR patients, focusing on conservative approaches. Methods: This study retrospectively analyzes 1365 patients evaluated by an expert multidisciplinary heart team (MDT) in a single center from 2015 to 2022. Treatments included surgery, catheter-based interventions, and conservative management. Propensity matching was utilized to compare surgery and conservative approaches. Results: Surgical intervention was associated with superior long-term survival outcomes compared to conservative and catheter-based treatments, particularly for degenerative MR (DMR). Survival rates of patients deemed by the MDT to have non-severe DMR were comparable to surgical patients (HR 1.07, 95% CI: 0.37-3.12, p = 0.90). However, non-severe functional MR (FMR) patients trended towards elevated mortality risk (HR 1.77, 95% CI: 0.94-3.31, p = 0.07). Pharmacological treatment for DMR was associated with significantly higher mortality compared to surgery (HR 8.0, 95% CI: 1.78-36.03, p = 0.001). Functional MR patients treated pharmacologically exhibited a non-significantly higher mortality risk compared to surgical intervention (HR 1.93, 95% CI: 0.77-4.77, p = 0.20). Conclusions: Survival analysis revealed significant benefits for surgical intervention, contrasting with elevated mortality risks associated with conservative management. "Watchful waiting" may be appropriate for non-severe DMR, while FMR may require closer monitoring. Further research is needed to assess the impact of regular follow-up or delayed surgery on survival rates, as pharmacological therapy has limited long-term efficacy for DMR.

Clinical impact and predictors of periprocedural myocardial injury among patients undergoing left bundle branch area pacing.

BACKGROUND: The clinical impact of Periprocedural myocardial injury (PMI) in patients undergoing permanent pacemaker implantation with Left Bundle Branch Area Pacing (LBBAP) is unknown. METHODS: 130 patients undergoing LBBAP from January 2020 to June 2021 and completing 12 months follow up were enrolled to assess the impact of PMI on composite clinical outcome (CCO) defined as any of the following: all-cause death, hospitalization for heart failure (HHF), hospitalization for acute coronary syndrome (ACS) and ventricular arrhythmias (VAs). High sensitivity Troponin T (HsTnT) was measured up to 24-h after intervention to identify the peak HsTnT values. PMI was defined as increased peak HsTnT values at least > 99th percentile of the upper reference limit (URL: 15 pg/ml) in patients with normal baseline values. RESULTS: PMI occurred in 72 of 130 patients (55%). ROC analysis yielded a post-procedural peak HsTnT cutoff of fourfold the URL for predicting the CCO (AUC: 0.692; p = 0.023; sensitivity 73% and specificity 71%). Of the enrolled patients, 20% (n = 26) had peak HsTnT > fourfold the URL. Patients with peak HsTnT > fourfold the URL exhibited a higher incidence of the CCO than patients with peak HsTnT ≤ fourfold the URL (31% vs. 10%; p = 0.005), driven by more frequent hospitalizations for ACS (15% vs. 3%; p = 0.010). Multiple (> 2) lead repositions attempts, the use of septography and stylet-driven leads were independent predictors of higher risk of PMI with peak HsTnT > fourfold the URL. CONCLUSIONS: PMI seems common among patients undergoing LBBAP and may be associated with an increased risk of clinical outcomes in case of more pronounced (peak HsTnT > fourfold the URL) myocardial damage occurring during the procedure.

Optimal Threshold and Interpatient Variability in Left Atrial Ablation Scar Assessment by Dark-Blood LGE CMR.

BACKGROUND: Dark-blood late gadolinium enhancement (LGE) cardiac magnetic resonance (CMR) has better correlation with bipolar voltage (BiV) to define ablation scar in the left atrium (LA) compared to conventional bright-blood LGE CMR. OBJECTIVES: This study sought to determine the optimal signal intensity threshold of dark-blood LGE CMR to identify LA ablation scar. METHODS: In 54 patients scheduled for atrial fibrillation ablation, image intensity ratios (IIRs) were derived from preprocedural dark-blood LGE CMR. In 26 patients without previous ablation, the upper limit of normal was derived from the 95th and 98th percentiles of pooled IIR values. In 28 patients with previous atrial fibrillation ablation, BiV was compared with the corresponding IIR. Receiver-operating characteristics analyses were employed to determine the optimal IIR threshold (ie, the point with the smallest distance to the upper left corner of the receiver-operating characteristics) for LA ablation scar (BiV ≤0.15 mV). RESULTS: Upper limit of normal corresponded to IIR values 1.16 and 1.21, yielding low sensitivities of 0.32 and 0.09 to detect LA ablation scar. Receiver-operating characteristics analysis of IIR and BiV comparison achieved a median area under the curve of 0.77. Median optimal IIR threshold for LA ablation scar was 1.09, with an average sensitivity of 0.73, specificity of 0.75, and accuracy of 0.71. Median IIR thresholds of 1.00 and 1.10 corresponded to 80% sensitivity and 80% specificity, respectively. There was considerable interpatient variability: optimal IIR thresholds per patient ranged from 1.01 to 1.22. CONCLUSIONS: The optimal IIR threshold to identify LA ablation scar by dark-blood LGE CMR is 1.09. Because of interpatient variability, the investigators recommend using a lower (1.00) and upper (1.10) threshold to prevent over- or underestimation of ablation scar.

Parameter subset reduction for imaging-based digital twin generation of patients with left ventricular mechanical discoordination.

BACKGROUND: Integration of a patient's non-invasive imaging data in a digital twin (DT) of the heart can provide valuable insight into the myocardial disease substrates underlying left ventricular (LV) mechanical discoordination. However, when generating a DT, model parameters should be identifiable to obtain robust parameter estimations. In this study, we used the CircAdapt model of the human heart and circulation to find a subset of parameters which were identifiable from LV cavity volume and regional strain measurements of patients with different substrates of left bundle branch block (LBBB) and myocardial infarction (MI). To this end, we included seven patients with heart failure with reduced ejection fraction (HFrEF) and LBBB (study ID: 2018-0863, registration date: 2019-10-07), of which four were non-ischemic (LBBB-only) and three had previous MI (LBBB-MI), and six narrow QRS patients with MI (MI-only) (study ID: NL45241.041.13, registration date: 2013-11-12). Morris screening method (MSM) was applied first to find parameters which were important for LV volume, regional strain, and strain rate indices. Second, this parameter subset was iteratively reduced based on parameter identifiability and reproducibility. Parameter identifiability was based on the diaphony calculated from quasi-Monte Carlo simulations and reproducibility was based on the intraclass correlation coefficient ( ICC ) obtained from repeated parameter estimation using dynamic multi-swarm particle swarm optimization. Goodness-of-fit was defined as the mean squared error ( χ 2 ) of LV myocardial strain, strain rate, and cavity volume. RESULTS: A subset of 270 parameters remained after MSM which produced high-quality DTs of all patients ( χ 2 < 1.6), but minimum parameter reproducibility was poor ( ICC min = 0.01). Iterative reduction yielded a reproducible ( ICC min = 0.83) subset of 75 parameters, including cardiac output, global LV activation duration, regional mechanical activation delay, and regional LV myocardial constitutive properties. This reduced subset produced patient-resembling DTs ( χ 2 < 2.2), while septal-to-lateral wall workload imbalance was higher for the LBBB-only DTs than for the MI-only DTs (p < 0.05). CONCLUSIONS: By applying sensitivity and identifiability analysis, we successfully determined a parameter subset of the CircAdapt model which can be used to generate imaging-based DTs of patients with LV mechanical discoordination. Parameters were reproducibly estimated using particle swarm optimization, and derived LV myocardial work distribution was representative for the patient's underlying disease substrate. This DT technology enables patient-specific substrate characterization and can potentially be used to support clinical decision making.

Assessment of ICD eligibility in non-ischaemic cardiomyopathy patients: a position statement by the Task Force of the Dutch Society of Cardiology.

International guidelines recommend implantation of an implantable cardioverter-defibrillator (ICD) in non-ischaemic cardiomyopathy (NICM) patients with a left ventricular ejection fraction (LVEF) below 35% despite optimal medical therapy and a life expectancy of more than 1 year with good functional status. We propose refinement of these recommendations in patients with NICM, with careful consideration of additional risk parameters for both arrhythmic and non-arrhythmic death. These additional parameters include late gadolinium enhancement on cardiac magnetic resonance imaging and genetic testing for high-risk genetic variants to further assess arrhythmic risk, and age, comorbidities and sex for assessment of non-arrhythmic mortality risk. Moreover, several risk modifiers should be taken into account, such as concomitant arrhythmias that may affect LVEF (atrial fibrillation, premature ventricular beats) and resynchronisation therapy. Even though currently no valid cut-off values have been established, the proposed approach provides a more careful consideration of risks that may result in withholding ICD implantation in patients with low arrhythmic risk and substantial non-arrhythmic mortality risk.

Impact of a Chronic Total Coronary Occlusion on the Incidence of Appropriate Implantable Cardioverter-Defibrillator Shocks and Mortality: A Substudy of the Dutch Outcome in ICD Therapy (DO-IT)) Registry.

BACKGROUND: Chronic total coronary occlusions (CTO) substantially increase the risk for sudden cardiac death. Among patients with chronic ischemic heart disease at risk for sudden cardiac death, an implantable cardioverter defibrillator (ICD) is the favored therapy for primary prevention of sudden cardiac death. This study sought to investigate the impact of CTOs on the risk for appropriate ICD shocks and mortality within a nationwide prospective cohort. METHODS AND RESULTS: This is a subanalysis of the nationwide Dutch-Outcome in ICD Therapy (DO-IT) registry of primary prevention ICD recipients in The Netherlands between September 2014 and June 2016 (n=1442). We identified patients with chronic ischemic heart disease (n=663) and assessed available coronary angiograms for CTO presence (n=415). Patients with revascularized CTOs were excluded (n=79). The primary end point was the composite of all-cause mortality and appropriate ICD shocks. Clinical follow-up was conducted for at least 2 years. A total of 336 patients were included, with an average age of 67±9 years, and 20.5% was female (n=69). An unrevascularized CTO was identified in 110 patients (32.7%). During a median follow-up period of 27 months (interquartile range, 24-32), the primary end point occurred in 21.1% of patients with CTO (n=23) compared with 11.9% in patients without CTO (n=27; P=0.034). Corrected for baseline characteristics including left ventricular ejection fraction, and the presence of a CTO was an independent predictor for the primary end point (hazard ratio, 1.82 [95% CI, 1.03-3.22]; P=0.038). CONCLUSIONS: Within this nationwide prospective registry of primary prevention ICD recipients, the presence of an unrevascularized CTO was an independent predictor for the composite outcome of all-cause mortality and appropriate ICD shocks.

The association between coronary artery calcification and vectorcardiography in mechanically ventilated COVID-19 patients: the Maastricht Intensive Care COVID cohort.

BACKGROUND: Coronary artery calcification (CAC) is associated with poor outcome in critically ill patients. A deterioration in cardiac conduction and loss of myocardial tissue could be an underlying cause. Vectorcardiography (VCG) and cardiac biomarkers provide insight into these underlying causes. The aim of this study was to investigate whether a high degree of CAC is associated with VCG-derived variables and biomarkers, including high-sensitivity troponin-T (hs-cTnT) and N-terminal pro-B-type natriuretic peptide (NT-proBNP). METHODS: Mechanically ventilated coronavirus-19 (COVID-19) patients with an available chest computed tomography (CT) and 12-lead electrocardiogram (ECG) were studied. CAC scores were determined using chest CT scans. Patients were categorized into 3 sex-specific tertiles: low, intermediate, and high CAC. Daily 12 leads-ECGs were converted to VCGs. Daily hs-cTnT and NT-proBNP levels were determined. Linear mixed-effects regression models examined the associations between CAC tertiles and VCG variables, and between CAC tertiles and hs-cTnT or NT-proBNP levels. RESULTS: In this study, 205 patients (73.2% men, median age 65 years [IQR 57.0; 71.0]) were included. Compared to the lowest CAC tertile, the highest CAC tertile had a larger QRS area at baseline (6.65 µVs larger [1.50; 11.81], p = 0.012), which decreased during admission (- 0.27 µVs per day [- 0.43; - 0.11], p = 0.001). Patients with the highest CAC tertile also had a longer QRS duration (12.02 ms longer [4.74; 19.30], p = 0.001), higher levels of log hs-cTnT (0.79 ng/L higher [0.40; 1.19], p < 0.001) and log NT-proBNP (0.83 pmol/L higher [0.30; 1.37], p = 0.002). CONCLUSION: Patients with a high degree of CAC had the largest QRS area and higher QRS amplitude, which decreased more over time when compared to patients with a low degree of CAC. These results suggest that CAC might contribute to loss of myocardial tissue during critical illness. These insights could improve risk stratification and prognostication of patients with critical illness.

Ultra-High-Frequency ECG in Cardiac Pacing and Cardiac Resynchronization Therapy: From Technical Concept to Clinical Application.

Identifying electrical dyssynchrony is crucial for cardiac pacing and cardiac resynchronization therapy (CRT). The ultra-high-frequency electrocardiography (UHF-ECG) technique allows instantaneous dyssynchrony analyses with real-time visualization. This review explores the physiological background of higher frequencies in ventricular conduction and the translational evolution of UHF-ECG in cardiac pacing and CRT. Although high-frequency components were studied half a century ago, their exploration in the dyssynchrony context is rare. UHF-ECG records ECG signals from eight precordial leads over multiple beats in time. After initial conceptual studies, the implementation of an instant visualization of ventricular activation led to clinical implementation with minimal patient burden. UHF-ECG aids patient selection in biventricular CRT and evaluates ventricular activation during various forms of conduction system pacing (CSP). UHF-ECG ventricular electrical dyssynchrony has been associated with clinical outcomes in a large retrospective CRT cohort and has been used to study the electrophysiological differences between CSP methods, including His bundle pacing, left bundle branch (area) pacing, left ventricular septal pacing and conventional biventricular pacing. UHF-ECG can potentially be used to determine a tailored resynchronization approach (CRT through biventricular pacing or CSP) based on the electrical substrate (true LBBB vs. non-specified intraventricular conduction delay with more distal left ventricular conduction disease), for the optimization of CRT and holds promise beyond CRT for the risk stratification of ventricular arrhythmias.

Automated cardiac arrest detection using a photoplethysmography wristband: algorithm development and validation in patients with induced circulatory arrest in the DETECT-1 study.

BACKGROUND: Unwitnessed out-of-hospital cardiac arrest is associated with low survival chances because of the delayed activation of the emergency medical system in most cases. Automated cardiac arrest detection and alarming using biosensor technology would offer a potential solution to provide early help. We developed and validated an algorithm for automated circulatory arrest detection using wrist-derived photoplethysmography from patients with induced circulatory arrests. METHODS: In this prospective multicentre study in three university medical centres in the Netherlands, adult patients (aged 18 years or older) in whom short-lasting circulatory arrest was induced as part of routine practice (transcatheter aortic valve implantation, defibrillation testing, or ventricular tachycardia induction) were eligible for inclusion. Exclusion criteria were a known bilateral significant subclavian artery stenosis or medical issues interfering with the wearing of the wristband. After providing informed consent, patients were equipped with a photoplethysmography wristband during the procedure. Invasive arterial blood pressure and electrocardiography were continuously monitored as the reference standard. Development of the photoplethysmography algorithm was based on three consecutive training cohorts. For each cohort, patients were consecutively enrolled. When a total of 50 patients with at least one event of circulatory arrest were enrolled, that cohort was closed. Validation was performed on the fourth set of included patients. The primary outcome was sensitivity for the detection of circulatory arrest. FINDINGS: Of 306 patients enrolled between March 14, 2022, and April 21, 2023, 291 patients were included in the data analysis. In the development phase (n=205), the first training set yielded a sensitivity for circulatory arrest detection of 100% (95% CI 94-100) and four false positive alarms; the second training set yielded a sensitivity of 100% (94-100), with six false positive alarms; and the third training set yielded a sensitivity of 100% (94-100), with two false positive alarms. In the validation phase (n=86), the sensitivity for circulatory arrest detection was 98% (92-100) and 11 false positive circulatory arrest alarms. The positive predictive value was 90% (95% CI 82-94). INTERPRETATION: The automated detection of induced circulatory arrests using wrist-derived photoplethysmography is feasible with good sensitivity and low false positives. These promising findings warrant further development of this wearable technology to enable automated cardiac arrest detection and alarming in a home setting. FUNDING: Dutch Heart Foundation (Hartstichting).

Utilization of and perceived need for simulators in clinical electrophysiology: results from an EHRA physician survey.

AIMS: Simulator training has been recently introduced in electrophysiology (EP) programmes in order to improve catheter manipulation skills without complication risks. The aim of this study is to survey the current use of EP simulators and the perceived need for these tools in clinical training and practice. METHODS AND RESULTS: A 20-item online questionnaire developed by the Scientific Initiatives Committee of the European Heart Rhythm Association (EHRA) in collaboration with EHRA Digital Committee was disseminated through the EHRA Scientific Research Network members, national EP groups, and social media platforms. Seventy-four respondents from 22 countries (73% males; 50% under 40 years old) completed the survey. Despite being perceived as useful among EP professionals (81%), EP simulators are rarely a part of the institutional cardiology training programme (20%) and only 18% of the respondents have an EP simulator at their institution. When available, simulators are mainly used in EP to train transseptal puncture, ablation, and mapping, followed by device implantation (cardiac resynchronization therapy [CRT], leadless, and conduction system pacing [CSP]). Almost all respondents (96%) believe that simulator programmes should be a part of the routine institutional EP training, hopefully developed by EHRA, in order to improve the efficacy and safety of EP procedures and in particular CSP 58%, CRT 42%, leadless pacing 38%, or complex arrhythmia ablations (VT 58%, PVI 45%, and PVC 42%). CONCLUSION: This current EHRA survey identified a perceived need but a lack of institutional simulator programme access for electrophysiologists who could benefit from it in order to speed up the learning curve process and reduce complications of complex EP procedures.

Integration of implantable device therapy in patients with heart failure. A clinical consensus statement from the Heart Failure Association (HFA) and European Heart Rhythm Association (EHRA) of the European Society of Cardiology (ESC).

Implantable devices form an integral part of the management of patients with heart failure (HF) and provide adjunctive therapies in addition to cornerstone drug treatment. Although the number of these devices is growing, only few are supported by robust evidence. Current devices aim to improve haemodynamics, improve reverse remodelling, or provide electrical therapy. A number of these devices have guideline recommendations and some have been shown to improve outcomes such as cardiac resynchronization therapy, implantable cardioverter-defibrillators and long-term mechanical support. For others, more evidence is still needed before large-scale implementation can be strongly advised. Of note, devices and drugs can work synergistically in HF as improved disease control with devices can allow for further optimization of drug therapy. Therefore, some devices might already be considered early in the disease trajectory of HF patients, while others might only be reserved for advanced HF. As such, device therapy should be integrated into HF care programmes. Unfortunately, implementation of devices, including those with the greatest evidence, in clinical care pathways is still suboptimal. This clinical consensus document of the Heart Failure Association (HFA) and European Heart Rhythm Association (EHRA) of the European Society of Cardiology (ESC) describes the physiological rationale behind device-provided therapy and also device-guided management, offers an overview of current implantable device options recommended by the guidelines and proposes a new integrated model of device therapy as a part of HF care.

Exploring QRS Area beyond Patient Selection in CRT-Can It Guide Left Ventricular Lead Placement?

Vectorcardiographic QRS area is a promising tool for patient selection and implantation guidance in cardiac resynchronization therapy (CRT). Research has mainly focused on the role of QRS area in patient selection for CRT. Recently, QRS area has been proposed as a tool to guide left ventricular lead placement in CRT. Theoretically, vector-based electrical information of ventricular fusion pacing, calculated from the basic 12-lead ECG, can give real-time insight into the extent of resynchronization at any LV lead position, as well as any selected electrode on the LV lead. The objective of this review is to provide an overview of the background of vectorcardiographic QRS area and its potential in optimizing LV lead location in order to optimize the benefits of CRT.

Sex-Specific Outcomes of LBBAP Versus Biventricular Pacing: Results From I-CLAS.

BACKGROUND: Cardiac resynchronization therapy (CRT) using biventricular pacing (BVP) has been associated with greater clinical improvement in women than men. Recently, left bundle branch area pacing (LBBAP) has been shown to be an alternative form of CRT. OBJECTIVES: The purpose of this study was to investigate sex-specific outcomes for death and heart failure events in a large, international, multicenter, cohort of patients undergoing CRT with BVP or LBBAP. METHODS: In this international study of 1,778 patients (575 female and 1203 male), sex-specific survival analysis was performed to compare the effect of LBBAP-CRT relative to BVP-CRT on the combined endpoint of death or heart failure hospitalization (HFH), and secondary endpoints of HFH only, and death alone. RESULTS: Female patients were more likely to have nonischemic cardiomyopathy and left bundle branch block (LBBB) and less likely to have hypertension, diabetes, or coronary artery disease than were male patients. Overall, female patients had a better result with LBBAP compared with BVP than did male patients, with a significant 36% reduction in death or HFH (HR: 0.64; 95% CI: 0.43 to 0.97; P = 0.03) and a significant 60% reduction in HFH alone (HR: 0.4; 95% CI: 0.24 to 0.69, P < 0.01). Women had a greater reduction in death or HFH among those with nonischemic cardiomyopathy (HR: 0.45 95% CI: 0.26 to 0.79; P < 0.01) and LBBB (HR: 0.49; 95% CI: 0.27 to 0.87; P < 0.01). Sex-specific echocardiographic outcomes were better in women than in men. CONCLUSIONS: Women obtained significantly greater reductions in the combined endpoint of death or HFH (primarily driven by reduction in HFH) with LBBAP compared with BVP among patients requiring CRT than did men.

Pericardial Fat Is Associated With Less Severe Multiorgan Failure Over Time in Patients With Coronavirus Disease-19: The Maastricht Intensive Care COVID Cohort.

PURPOSE: Pericardial fat (PF) and epicardial adipose tissue (EAT) may enhance the proinflammatory response in corona virus-19 (COVID-19) patients. Higher PF and EAT volumes might result in multiorgan failure and explain unfavorable trajectories.The aim of this study was to examine the association between the volume of PF and EAT and multiorgan failure over time. MATERIALS AND METHODS: All mechanically ventilated COVID-19 patients with an available chest computed tomography were prospectively included (March-June 2020). PF and EAT volumes were quantified using chest computed tomography scans. Patients were categorized into sex-specific PF and EAT tertiles. Variables to calculate Sequential Organ Failure Assessment (SOFA) scores were collected daily to indicate multiorgan failure. Linear mixed-effects regression was used to investigate the association between tertiles for PF and EAT volumes separately and serial SOFA scores over time. All models were adjusted. RESULTS: Sixty-three patients were divided into PF and EAT tertiles, with median PF volumes of 131.4 mL (IQR [interquartile range]: 115.7, 143.2 mL), 199.8 mL (IQR: 175.9, 221.6 mL), and 318.8 mL (IQR: 281.9, 376.8 mL) and median EAT volumes of 69.6 mL (IQR: 57.0, 79.4 mL), 107.9 mL (IQR: 104.6, 115.1 mL), and 163.8 mL (IQR: 146.5, 203.1 mL). Patients in the highest PF tertile had a statistically significantly lower SOFA score over time (1.3 [-2.5, -0.1], P =0.033) compared with the lowest PF tertile. EAT tertiles were not significantly associated with SOFA scores over time. CONCLUSION: A higher PF volume is associated with less multiorgan failure in mechanically ventilated COVID-19 patients. EAT volumes were not associated with multiorgan failure.

Left ventricular lead placement in cardiac resynchronization therapy: Current data and potential explanations for the lack of benefit.

The present article reviews the literature on image-guided cardiac resynchronization therapy (CRT) studies. Improved outcome to CRT has been associated with the placement of a left ventricular (LV) lead in the latest activated segment free from scar. The majority of randomized controlled trials investigating guided LV lead implantation did not show superiority over conventional implantation approaches. Several factors may contribute to this paradoxical observation, including inclusion criteria favoring patients with left bundle branch block who already respond well to conventional anatomical LV lead implantation, differences in activation wavefronts during simultaneous right ventricular and LV pacing, incorrect definition of target regions, and limitations in coronary venous anatomy that prevent access to target regions that are detected by imaging. It is imperative that exclusion of patients lacking access to target regions from these studies would lead to larger benefit of image-guided CRT.

Arrhythmic Risk in Biventricular Pacing Compared With Left Bundle Branch Area Pacing: Results From the I-CLAS Study.

BACKGROUND: Left bundle branch area pacing (LBBAP) may be associated with greater improvement in left ventricular ejection fraction and reduction in death or heart failure hospitalization compared with biventricular pacing (BVP) in patients requiring cardiac resynchronization therapy. We sought to compare the occurrence of sustained ventricular tachycardia (VT) or ventricular fibrillation (VF) and new-onset atrial fibrillation (AF) in patients undergoing BVP and LBBAP. METHODS: The I-CLAS study (International Collaborative LBBAP Study) included patients with left ventricular ejection fraction ≤35% who underwent BVP or LBBAP for cardiac resynchronization therapy between January 2018 and June 2022 at 15 centers. We performed propensity score-matched analysis of LBBAP and BVP in a 1:1 ratio. We assessed the incidence of VT/VF and new-onset AF among patients with no history of AF. Time to sustained VT/VF and time to new-onset AF was analyzed using the Cox proportional hazards survival model. RESULTS: Among 1778 patients undergoing cardiac resynchronization therapy (BVP, 981; LBBAP, 797), there were 1414 propensity score-matched patients (propensity score-matched BVP, 707; propensity score-matched LBBAP, 707). The occurrence of VT/VF was significantly lower with LBBAP compared with BVP (4.2% versus 9.3%; hazard ratio, 0.46 [95% CI, 0.29-0.74]; P<0.001). The incidence of VT storm (>3 episodes in 24 hours) was also significantly lower with LBBAP compared with BVP (0.8% versus 2.5%; P=0.013). Among 299 patients with cardiac resynchronization therapy pacemakers (BVP, 111; LBBAP, 188), VT/VF occurred in 8 patients in the BVP group versus none in the LBBAP group (7.2% versus 0%; P<0.001). In 1194 patients with no history of VT/VF or antiarrhythmic therapy (BVP, 591; LBBAP, 603), the occurrence of VT/VF was significantly lower with LBBAP than with BVP (3.2% versus 7.3%; hazard ratio, 0.46 [95% CI, 0.26-0.81]; P=0.007). Among patients with no history of AF (n=890), the occurrence of new-onset AF >30 s was significantly lower with LBBAP than with BVP (2.8% versus 6.6%; hazard ratio, 0.34 [95% CI, 0.16-0.73]; P=0.008). The incidence of AF lasting >24 hours was also significantly lower with LBBAP than with BVP (0.7% versus 2.9%; P=0.015). CONCLUSIONS: LBBAP was associated with a lower incidence of sustained VT/VF and new-onset AF compared with BVP. This difference remained significant after adjustment for differences in baseline characteristics between patients with BVP and LBBAP. Physiological resynchronization by LBBAP may be associated with lower risk of arrhythmias compared with BVP.

Left Atrial Function in Patients with Titin Cardiomyopathy.

BACKGROUND: Truncating variants in titin (TTNtv) are the most prevalent genetic etiology of dilated cardiomyopathy (DCM). Although TTNtv has been associated with atrial fibrillation, it remains unknown whether and how left atrial (LA) function differs between patients with DCM with and without TTNtv. We aimed to determine and compare LA function in patients with DCM with and without TTNtv and to evaluate whether and how left ventricular (LV) function affects the LA using computational modeling. METHODS AND RESULTS: Patients with DCM from the Maastricht DCM registry that underwent genetic testing and cardiovascular magnetic resonance (CMR) were included in the current study. Subsequent computational modeling (CircAdapt model) was performed to identify potential LV and LA myocardial hemodynamic substrates. In total, 377 patients with DCM (n = 42 with TTNtv, n = 335 without a genetic variant) were included (median age 55 years, interquartile range [IQR] 46-62 years, 62% men). Patients with TTNtv had a larger LA volume and decreased LA strain compared with patients without a genetic variant (LA volume index 60 mLm-2 [IQR 49-83] vs 51 mLm-2 [IQR 42-64]; LA reservoir strain 24% [IQR 10-29] vs 28% [IQR 20-34]; LA booster strain 9% [IQR 4-14] vs 14% [IQR 10-17], respectively; all P < .01). Computational modeling suggests that while the observed LV dysfunction partially explains the observed LA dysfunction in the patients with TTNtv, both intrinsic LV and LA dysfunction are present in patients with and without a TTNtv. CONCLUSIONS: Patients with DCM with TTNtv have more severe LA dysfunction compared with patients without a genetic variant. Insights from computational modeling suggest that both intrinsic LV and LA dysfunction are present in patients with DCM with and without TTNtv.

Repurposing catheter ablation work-up to detect expiratory airflow limitation in patients with atrial fibrillation.

Background: In atrial fibrillation (AF) patients, presence of expiratory airflow limitation may negatively impact treatment outcomes. AF patients are not routinely screened for expiratory airflow limitation, but existing examinations can help identify at-risk individuals. We aimed to assess the diagnostic value of repurposing existing assessments from the pre-ablation work-up to identify and understand the characteristics of affected patients. Methods: We screened 110 consecutive AF patients scheduled for catheter ablation with handheld spirometry. Routine pre-ablation work-up included cardiac computed tomographic angiography (CCTA), transthoracic echocardiography and polygraphy. CCTA was analyzed qualitatively for emphysema and airway abnormalities. Multivariate logistic regression analysis was performed to determine predictors of expiratory airflow limitation. Results: We found that 25 % of patients had expiratory airflow limitation, which was undiagnosed in 86 % of these patients. These patients were more likely to have pulmonary abnormalities on CCTA, including emphysema (odds ratio [OR] 4.2, 95 % confidence interval [CI] 1.12-15.1, p < 0.05) and bronchial wall thickening (OR 2.6, 95 % CI 1.0-6.5, p < 0.05). The absence of pulmonary abnormalities on CCTA accurately distinguished patients with normal lung function from those with airflow limitation (negative predictive value: 85 %). Echocardiography and polygraphy did not contribute significantly to identifying airflow limitation. Conclusions: In conclusion, routine pre-ablation CCTA can detect pulmonary abnormalities in AF patients with airflow limitation, guiding further pulmonary assessment. Future studies should investigate its impact on ablation procedure success.