Is His-optimized superior to conventional cardiac resynchronization therapy in improving heart failure? Results from a propensity-matched study

European Society of Cardiology (ESC) clinical consensus statement on indications for conduction system pacing, with special contribution of the European Heart Rhythm Association of the ESC and endorsed by the Asia Pacific Heart Rhythm Society, the Canadian Heart Rhythm Society, the Heart Rhythm Society, and the Latin American Heart Rhythm Society

Conduction system pacing (CSP) is being increasingly adopted as a more physiological alternative to right ventricular and biventricular pacing. Since the 2021 European Society of Cardiology pacing guidelines, there has been growing evidence that this therapy is safe and effective. Furthermore, left bundle branch area pacing was not covered in these guidelines due to limited evidence at that time. This Clinical Consensus Statement provides advice on indications for CSP, taking into account the significant evolution in this domain.

Case Report: Dual-chamber pacemaker for hypertrophic cardiomyopathy with bradyarrhythmia and idiopathic pericardial effusion: a report of two cases and literature review

Background

Hypertrophic cardiomyopathy (HCM) is an autosomal dominant disorder characterized by asymmetric hypertrophy of the ventricles and the ventricular septum, leading to subsequent left ventricular outflow tract (LVOT) obstruction and diastolic dysfunction. Typically, patients with HCM experience sinus tachycardia and sinus arrest relatively infrequently. In addition, the concurrent occurrence of HCM with non-surgically induced (ablation or myectomy) bradyarrhythmia and idiopathic pericardial effusion in adult patients has not been previously reported.

Case summary

In this report, we present two elderly female patients with HCM who exhibited sinus bradycardia and sinus arrest, one of whom also presented with moderate pericardial effusion, they all presented with chest tightness. To manage the complex comorbidities, we opted for dual-chamber pacemaker implantation. Subsequent examinations and follow-up revealed that pacing significantly reduced LVOT obstruction and corrected heart rhythm. Additionally, there was no significant progression of pericardial effusion.

Discussion

The primary strategies for alleviating LVOT obstruction involve altering the structure of the septum, including septal myectomy (SME), alcohol septal ablation (ASA), and septal radiofrequency ablation. Meanwhile, a dual-chamber pacemaker can treat HCM by changing the sequence of myocardial contraction. Although pacemakers have been considered an inferior alternative due to their relatively large residual obstruction, their benefits may be significantly underestimated. This report underscores the additional efficacy of dual-chamber pacemakers in managing HCM, particularly in patients complicated by sinus node dysfunction and idiopathic pericardial effusion.

Case Report: Painful left bundle branch block syndrome complicated with vasovagal syncope

Background

Painful left bundle branch block (LBBB) syndrome is an uncommon disease that is defined as intermittent episodes of angina associated with simultaneous LBBB changes on an electrocardiogram (ECG) with the absence of flow-limiting coronary artery disease or ischemia on functional testing. Vasovagal syncope (VVS) is the most common cause of syncope and can be provoked by sublingual nitroglycerin (NTG). Herein, we report a case of painful LBBB syndrome complicated with VVS, which was misdiagnosed as acute coronary syndrome and cardiogenic shock.

Case summary

A 62-year-old woman presented with intermittent exertional chest pain for 3 years and deteriorated for 2 weeks. An ECG, transthoracic echocardiography, and laboratory test results were all normal. Exercise treadmill testing induced chest pain, accompanied by new-onset LBBB. She fainted after finishing the test and receiving sublingual NTG, with a rapid decline in heart rate and blood pressure, which was relieved by 0.5 mg of atropine administered intravenously. Coronary angiography showed no evidence of obstructive lesions. Isoprenaline stress echocardiography induced chest pain and rate-dependent LBBB and showed interventricular/intraventricular desynchrony simultaneously. A head-up tilt test verified mixed VVS in the provocative phase. A diagnosis of painful LBBB syndrome complicated with VVS induced by sublingual NTG was made. The patient received an extended-release metoprolol succinate tablet and had no symptoms at a 1-year follow-up.

Conclusion

Painful LBBB syndrome is an uncommon cause of chest pain and is often overlooked by physicians. Misdiagnosis and mistreatment of painful LBBB syndrome may even cause secondary damage, such as VVS induced by sublingual NTG, which is usually used to alleviate angina.

Effectiveness of bundle of His pacing for cardiac resynchronization therapy in patients with heart failure combined with wide QRS complex: a meta-analysis

OBJECTIVE

To evaluate systematically the feasibility and effectiveness of His Bundle Pacing (HBP) for cardiac resynchronization therapy.

METHODS

A comprehensive search was conducted in PubMed, EMbase, WOS, Cochrane Library, Medline, and SinoMed for studies published between December 2003 and December 2023. Primary clinical outcomes included implantation success, QRS wave duration, pacing threshold, left ventricular ejection fraction (LVEF), left ventricular end-diastolic diameter (LVEDD), New York Heart Association (NYHA) cardiac function class, and complications. Data were extracted and summarized, and meta-analysis was performed by Revman 5.3 software.

RESULTS

Fourteen studies involving a total of 555 patients were included. The overall success rate for HBP implantation was 83.2% (462/555). Compared to baseline values, QRS duration was significantly reduced (MD=48.29, 95% CI: 45.20 to 51.38, P<0.01, I2=85%), LVEF was significantly increased (MD=-13.62, 95% CI: -15.46 to -11.79, P<0.01, I2=74%), LVEDD was smaller (MD=5.83, 95% CI: 4.44-7.22, P<0.01, I2=78.2%), and NYHA showed significant improvement (MD=1.24, 95% CI: 1.14-1.35, P<0.01, I2=97.2%). At follow-up, pacing threshold increased (MD=-0.28, 95% CI: -0.43 to -0.12, P<0.01, I2=0%), and pacing impedance decreased (MD=51.62, 95% CI: 23.67 to 79.56, P<0.01, I2=56%).

CONCLUSION

HBP is effective for cardiac resynchronization therapy. HBP significantly reduces QRS duration and improves LVEF in heart failure patients.

Atrioventricular node ablation for atrial fibrillation in the era of conduction system pacing

Despite key advances in catheter-based treatments, the management of persistent atrial fibrillation (AF) remains a therapeutic challenge in a significant subset of patients. While success rates have improved with repeat AF ablation procedures and the concurrent use of antiarrhythmic drugs, the likelihood of maintaining sinus rhythm during long-term follow-up is still limited. Atrioventricular node ablation (AVNA) has returned as a valuable treatment option given the recent developments in cardiac pacing. With the advent of conduction system pacing, AVNA has seen a revival where pacing-induced cardiomyopathy after AVNA is felt to be overcome. This review will discuss the role of permanent pacemaker implantation and AVNA for AF management in this new era of conduction system pacing. Specifically, this review will discuss the haemodynamic consequences of AF and the mechanisms through which 'pace-and-ablate therapy' enhances outcomes, analyse historical and more recent literature across various pacing methods, and work to identify patient groups that may benefit from earlier implementation of this approach.

Atrial Fibrillation and Mortality after Gastrointestinal Surgery: Insights from a Systematic Review and Meta-Analysis

BACKGROUND

Heart failure, stroke and death are major dangers associated with atrial fibrillation (AF), a common abnormal heart rhythm. Having a gastrointestinal (GI) procedure puts patients at risk for developing AF, especially after large abdominal surgery. Although earlier research has shown a possible connection between postoperative AF and higher mortality, the exact nature of this interaction is yet uncertain.

METHODS

To investigate the relationship between AF and death after GI procedures, this research carried out a thorough meta-analysis and systematic review of randomized controlled studies or clinical trials. Finding relevant randomized controlled trials (RCTs) required a comprehensive search across many databases. Studies involving GI surgery patients with postoperative AF and mortality outcomes were the main focus of the inclusion criteria. We followed PRISMA and Cochrane Collaboration protocols for data extraction and quality assessment, respectively.

RESULTS

After GI surgery, there was no statistically significant difference in mortality between the AF and non-AF groups, according to an analysis of the available trials (p = 0.97). The mortality odds ratio (OR) was 1.03 (95% CI [0.24, 4.41]), suggesting that there was no significant correlation. Nevertheless, there was significant heterogeneity throughout the trials, which calls for careful interpretation.

CONCLUSION

Despite the lack of a significant link between AF and death after GI surgery in our study, contradictory data from other research highlight the intricacy of this relationship. Discrepancies may arise from variations in patient demographics, research methodology and procedural problems. These results emphasize the necessity for additional extensive and varied studies to fully clarify the role of AF in postoperative mortality in relation to GI procedures. Comprehending the subtleties of this correlation might enhance future patient outcomes and contribute to evidence-based therapeutic decision making.

Electrical Storm Induced by Cardiac Resynchronization: Efficacy of the Multipoint Pacing Stimulation

Although cardiac resynchronization therapy (CRT) reduces morbidity and mortality and reverses left ventricular (LV) remodeling in heart failure patients with LV electrical dyssynchrony, induced proarrhythmia has been reported. The mechanism of CRT-induced proarrhythmia remains under debate. In this case report, a description of how LV pacing induced polymorphic ventricular tachycardia immediately after the initiation of CRT has been reported. By changing the pacing configuration using a multipoint pacing stimulation, we can assume that induced ventricular tachycardia is related to the reentry mechanism facilitated by the unidirectional block. As a result, a multipoint pacing (MPP) configuration near the scar area can avoid the onset of a unidirectional block with the establishment of the reentry phenomenon, thus avoiding induced VTs.

LECOM (Lead Extraction COMplexity): A New Scoring System for Predicting a Difficult Procedure

(1) Background: Transvenous lead extraction (TLE) can become far more complex when unanticipated difficulties arise. The aim was to develop a simple scoring system that allows for the prediction of the difficulty and complexity of this significant procedure. (2) Methods: Based on analysis of 3741 TLE procedures with and without complicating factors (extended fluoroscopy time, need for second-line instruments, and advanced techniques and instruments), a five-point Complex Indicator of Difficulty of (TLE) Procedure (CID-TLEP) scale was developed. Two or more points on the CID-TLEP scale indicate a higher level of procedure complexity. (3) Results: Patient age below 51 years at first CIED implantation, number of abandoned leads, number of previous procedures, passive fixation and multiple leads to be extracted, and a ratio of dwell time of oldest lead to patient age during TLE of >0.13 are significant predictors of higher levels of lead extraction complexity. The ROC analysis demonstrates that a point total (being the sum of the odds ratios of the above variables) of >9.697 indicates a 21.83% higher probability of complex TLE (sensitivity 74.08%, specificity 74.46%). Finally, a logistic function was calculated, and we constructed a simple equation for lead extraction complexity that can predict the probability of a difficult procedure. The risk of complex extraction (as a percentage) is calculated as [1/(1 + 55.34 · 0.754X)] · 100 (p < 0.001). (4) Conclusion: The LECOM score can effectively predict the risk of a difficult transvenous lead extraction procedure, and predicting the probability of a more complex procedure may help clinicians in planning lead removal and improving patient management.

Optimal Cardiac Resynchronization Therapy with Conduction System Pacing Guided by Electro-Anatomical Mapping: A Case Report

INTRODUCTION

Biventricular pacing has been the gold standard for cardiac resynchronization therapy in patients with left bundle branch block and severely reduced left ventricular ejection fraction for decades. However, in the past few years, this role has been challenged by the promising results of conduction system pacing in these patients, which has proven non-inferior and, at times, superior to biventricular pacing regarding left ventricular function outcomes. One of the most important limitations of both procedures is the long fluoroscopy times.

CASE DESCRIPTION

We present the case of a 60-year-old patient with non-ischemic dilated cardiomyopathy and left bundle branch block in whom conduction system pacing was chosen as the first option for resynchronization therapy. A 3D electro-anatomical mapping system was used to guide the lead to the His bundle region, where correction was observed at high amplitudes, and afterward to the optimal septal penetration site. After reaching the left endocardium, left bundle branch pacing achieved a narrow, paced QRS complex with low fluoroscopy exposure. The three-month follow-up showed a significant improvement in clinical status and left ventricular function.

CONCLUSION

Since conduction system pacing requires a great deal of precision, targeting specific, narrow structures inside the heart, 3D mapping is a valuable tool that increases the chances of success, especially in patients with complex anatomies, such as those with indications for cardiac resynchronization therapy.

One-Year Mortality in Patients Undergoing an Implantable Cardioverter Defibrillator or Cardiac Resynchronization Therapy Pulse Generator Replacement: Identifying Patients at Risk

Implantable cardioverter defibrillators (ICDs) significantly contribute to the prevention of sudden cardiac death in selected patients. However, it is essential to identify those who are likely to not have benefit from an ICD and to defer a pulse generator exchange. Easily implementable guidelines for individual risk stratification and decision making are lacking. This study investigates the 1-year mortality of patients who underwent an ICD or cardiac resynchronization therapy with defibrillator function (CRT-D) pulse generator replacement in a contemporary real-world tertiary hospital setting. The cause of death and patient- and procedure-related factors are stratified, and predictive values for 1-year mortality are evaluated. Patients with a follow-up of ≥365 days (or prior mortality) after an ICD or CRT-D exchange at the Leiden University Medical Center from 1 January 2018 until 31 December 2021 were eligible. In total, 588 patients were included (77% male, 69 [60-76] years old, 59% primary prevention, 46% ischemic cardiomyopathy and 37% mildly reduced left ventricular ejection fraction (LVEF)). Patients undergoing a CRT-D replacement or upgrade had a significantly higher 1-year all-cause mortality (10.7% and 11.9%, respectively) compared to patients undergoing ICD (2.8%) exchange (p = 0.002). LVEF ≤ 30%, New York Heart Association class ≥ 3, estimated glomerular filtration rate ≤ 30 mL/min/m2 and haemoglobin ≤ 7 mmol/L were independently associated with mortality within 1 year after pulse generator replacement. There is a growing need for prospectively validated risk scores to weight individualized risk of mortality with the expected ICD therapy benefit and to support a well-informed, shared decision-making process.

Clinical outcomes of conduction system pacing versus biventricular pacing for cardiac resynchronization therapy: A systematic review and meta-analysis

INTRODUCTION

Conduction system pacing (CSP) is observed to produce greater improvements in echocardiographic and hemodynamic parameters as compared to conventional biventricular pacing (BiVP). However, whether these surrogate endpoints directly translate to improvements in hard clinical outcomes such as death and heart failure hospitalization (HFH) with CSP remains uncertain as studies reporting these outcomes are scarce. The aim of this meta-analysis was to analyze the existing data to compare the clinical outcomes of CSP versus BiVP.

METHODS

A systematic search of the Embase and PubMed database was performed for studies comparing CSP and BiVP for patients indicated to receive a CRT device. The coprimary endpoints were all-cause mortality and HFH. Other secondary outcomes included change in left ventricular ejection fraction (LVEF), change in NYHA class, and increase in NYHA class ≥1. A random-effects model was chosen a priori to analyze the composite effects given the anticipated heterogeneity of included trials.

RESULTS

Twenty-one studies (4 randomized and 17 observational) were identified reporting either primary outcome and were included in the meta-analysis. In total 1960 patients were assigned to CSP and 2367 to BiVP. Median follow-up time was 10.1 months (ranging 2-33 months). CSP was associated with a significant reduction in all-cause mortality (odds ratio [OR] 0.68, 95% confidence interval [CI]: 0.56-0.83) and HFH (OR 0.52, 95% CI: 0.44-0.63). Mean improvement in LVEF was also greater with CSP (mean difference 4.26, 95% CI: 3.19-5.33). Reduction in NYHA class was significantly greater with CSP (mean difference -0.36, 95% CI: -0.49 to -0.22) and the number of patients with an increase in NYHA class ≥1 was significantly greater with CSP (OR 2.02, 95% CI: 1.70-2.40).

CONCLUSIONS

CSP was associated with a significant reduction in all-cause mortality and HFH when compared to conventional BiVP for CRT. Further large-scale randomized trials are needed to verify these observations.

Long-Term Outcomes of Transvenous Lead Extraction: A Comparison in Patients with or without Infection from the Italian Region with the Oldest Population

BACKGROUND

The gold standard for the treatment of cardiac implantable electronic devices (CIEDs)-related infection and lead malfunction is transvenous lead extraction (TLE). To date, the risk of mortality directly related to TLE procedures is relatively low, but data on post-procedural and long-term mortality are limited, even more in the aging population.

METHODS

Consecutive patients with CIEDs who underwent TLE were retrospectively studied. The primary outcome was the endpoint of death, considering independent predictors of long-term clinical outcomes in the TLE aging population comparing patients with and without infection.

RESULTS

One hundred nineteen patients (male 77%; median age 76 years) were included in the analysis. Eighty-two patients (69%) documented infection, and thirty-seven (31%) were extracted for a different reason. Infected patients were older (80 vs. 68 years, p-value > 0.001) with more implanted catheters (p-value < 0.001). At the last follow-up (FU) available (median FU 4.1 years), mortality reached 37% of the patient population, showing a statistically significant difference between infected versus non-infected groups. At univariable analysis, age at TLE, atrial fibrillation, and anemia remained significant correlates of mortality; at multivariable analysis, only patients with anemia and atrial fibrillation have a 2.3-fold (HR 2.34; CI 1.16-4.75) and a 2.5-fold (HR 2.46; CI 1.33-4.54) increased rate of death, respectively.

CONCLUSION

Our long-term data showed that aging patients who underwent TLE for CIED-related infection exhibit a high mortality risk during a long-term follow-up, potentially leading to a rapid and effective procedural approach in this patient population.

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.

Case report: Torsade de pointes induced by the bigeminy result from retrograde ventriculoatrial activation in VVI pacing and resolved by intentional atrial pacing

Introduction

While pacing has been used for long QT syndrome (LQTs), the optimal pacing modality is controversial.

Case

We report a woman with bradycardia and a recently implanted single-chamber pacemaker experienced multiple syncope. No device dysfunction was found. Multiple Torsade de Pointes (TdP) induced by the bigeminy result from retrograde ventriculoatrial (VA) activation in VVI pacing were demonstrated in the scenario of previously unidentified LQTs. Replacement for a dual-chamber ICD and intentional atrial pacing eliminated the VA conduction and symptoms.

Conclusion

Pacing without atrioventricular sequence might be catastrophic in LQTs. Atrial pacing and atrioventricular synchrony should be highlighted.

Left ventricular electrical potential measured by the NOGA XP electromechanical mapping method as a predictor of response to cardiac resynchronization therapy

Objectives

The aim of the study was to determine whether left ventricular electrical potential measured by electromechanical mapping with the NOGA XP system has predictive value for response to CRT.

Background

Approximately 30% of patients who undergo cardiac resynchronization therapy do not see the expected effects.

Methods

The group of 38 patients qualified for CRT implantation were included in the study, of which 33 patients were analyzed. A 15% reduction in ESV after 6 months of pacing was used as a criterion for a positive response to CRT. The mean value and sum of unipolar and bipolar potentials obtained by mapping with the NOGA XP system and their predictive value in relation to the effect of CRT were analyzed using a bulls-eye projection at three levels: 1) the global value of the left ventricular (LV) potentials, 2) the potentials of the individual LV walls and 3) the mean value of the potentials of the individual segments (basal and middle) of the individual LV walls.

Results

24 patients met the criterion of a positive response to CRT vs. 9 non-responders. At the global analysis stage, the independent predictors of favorable response to CRT were the sum of the unipolar potential and bipolar mean potential. In the analysis of individual left ventricular walls, the mean bipolar potential of the anterior and posterior wall and in the unipolar system, mean septal potential was found to be an independent predictor of favorable response to CRT. In the detailed segmental analysis, the independent predictors were the bipolar potential of the mid-posterior wall segment and the basal anterior wall segment.

Conclusions

Measurement of bipolar and unipolar electrical potentials with the NOGA XP system is a valuable method for predicting a favorable response to CRT.

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.

Feasibility and safety of left bundle branch area pacing-cardiac resynchronization therapy in elderly patients

BACKGROUND

Left bundle branch area pacing (LBBAP) is an emerging technique to achieve cardiac resynchronization therapy (CRT), but its feasibility and safety in elderly patients with heart failure with reduced ejection fraction and left bundle branch block is hardly investigated.

METHODS

We enrolled consecutive patients with an indication for CRT comparing pacing parameters and complication rates of LBBAP-CRT in elderly patients (≥ 75 years) versus younger patients (< 75 years) over a 6-month follow-up.

RESULTS

LBBAP was successful in 55/60 enrolled patients (92%), among which 25(45%) were elderly. In both groups, LBBAP significantly reduced the QRS duration (elderly group: 168 ± 15 ms to 136 ± 12 ms, p < 0.0001; younger group: 166 ± 14 ms to 134 ± 11 ms, p < 0.0001) and improved LVEF (elderly group: 28 ± 5% to 40 ± 7%, p < 0.0001; younger group: 29 ± 5% to 41 ± 8%, p < 0.0001). The pacing threshold was 0.9 ± 0.8 V in the elderly group vs. 0.7 ± 0.5 V in the younger group (p = 0.350). The R wave was 9.5 ± 3.9 mV in elderly patients vs. 10.7 ± 2.7 mV in younger patients (p = 0.341). The fluoroscopic (elderly: 13 ± 7 min vs. younger: 11 ± 7 min, p = 0.153) and procedural time (elderly: 80 ± 20 min vs. younger: 78 ± 16 min, p = 0.749) were comparable between groups. Lead dislodgement occurred in 2(4%) patients, 1 in each group (p = 1.000). Intraprocedural septal perforation occurred in three patients (5%), 2(8%) in the elderly group (p = 0.585). One patient (2%) in the elderly group had a pocket infection.

CONCLUSIONS

LBBAP is a feasible and safe technique for delivering physiological pacing in elderly patients who are candidates for CRT with suitable pacing parameters and low complication rates.

The impacts of preoperative frailty on readmission after cardiac implantable electrical device implantation

Cardiac implantable electrical devices (CIED) such as pacemakers, implantable cardioverter defibrillators, and cardiac resynchronization therapies are generally recommended for older patients and those with severe heart failure (HF). However, there is currently a lack of evidence on the relationship between frailty and readmission rates among patients with CIED. This study investigated whether preoperative frailty influenced readmission rates among patients with CIED over a one-year period following implantation. The study retrospectively analyzed 101 patients who underwent CIED implantations. To compare frailty-based differences in their characteristics and readmission rates, these participants were categorized into frailty and non-frailty groups via the modified frailty index (mFI). The frailty group had a significantly higher readmission rate than the non-frailty group (non-frailty group vs. frailty group = 1 vs. 8 patients: P < 0.05). Further, a multivariate analysis showed that frailty was a significant readmission factor. Based on individual analyses with/without histories of HF, the readmission rate also tended to be higher among individuals considered frail via the mFI (readmission rate in HF patients: non-frailty group vs. frailty group = 1 vs. 5 patients: P = 0.65; non-HF patients: non-frailty group vs. frailty group = 0 vs. 3 patients: P = 0.01). Participants with preoperative frailty showed higher readmission rates within a one-year period following implantation compared to those without preoperative frailty. This tendency was consistent regardless of HF history. The mFI may thus help predict readmission among patients with CIED.

Cardiac-Device Implantation and Pneumothorax—A Symptom-Based Approach: Experience from a District General Hospital

In patients undergoing cardiac-device implantation, pneumothorax incidence occurs in 1–6%, and is more common in women over 80 years of age with chronic obstructive pulmonary disease (COPD). The aim of this study was to do a service review to identify ways to improve care delivery. Caldicott approval was gained. Those complicated by a pneumothorax were further analysed regarding basic demographics and pleural interventions and outcomes. Continuous variables are presented as mean (range) or median (with interquartile ranges) and categorical variables are presented as percentages where appropriate. A total of 2056 implantation episodes from January 2010 to December 2020 occurred with 70 pneumothoraxes (3.4%), which were all related to pacemaker insertion. The mean age was 68.1 years (17–97), 39 were female, and 31 were male. A total of 36 pneumothoraxes were small and were 34 large according to British Thoracic Society (BTS) criteria. We initially observed 56 patients with minimal or no symptoms (30 were large pneumothoraxes), with five requiring intercostal drainage (ICD). A total of 14 pneumothoraxes were treated with ICD as a first-line treatment: the mean age was 78 years (69–89) and eight patients had COPD. Five pneumothoraxes were large. All had significant symptoms. All pneumothoraxes resolved within six weeks with no associated mortality.

Alternative pacing strategies for optimal cardiac resynchronization therapy

Cardiac resynchronization therapy (CRT) via biventricular pacing (BVP) improves morbidity, mortality, and quality of life, especially in subsets of patients with impaired cardiac function and wide QRS. However, the rate of unsuccessful or complicated left ventricular (LV) lead placement through coronary sinus is 5-7%, and the rate of "CRT non-response" is approximately 30%. These reasons have pushed physicians and engineers to collaborate to overcome the challenges of LV lead implantation. Thus, various alternatives to BVP have been proposed to improve CRT effectiveness. His bundle pacing (HBP) has been increasingly used by activating the His-Purkinje system but is constrained by challenging implantation, low success rates, high and often unstable thresholds, and low perception. Therefore, the concept of pacing a specialized conduction system distal to the His bundle to bypass the block region was proposed. Multiple clinical studies have demonstrated that left bundle branch area pacing (LBBAP) has comparable electrical resynchronization with HBP but is superior in terms of simpler operation, higher success rates, lower and stable capture thresholds, and higher perception. Despite their well-demonstrated effectiveness, the transvenous lead-related complications remain major limitations. Recently, leadless LV pacing has been developed and demonstrated effective for these challenging patient cohorts. This article focuses on the current state and latest progress in HBP, LBBAP, and leadless LV pacing as alternatives for failed or non-responsive conventional CRT as well as their limits and prospects.

His-Optimized and Left Bundle Branch-Optimized Cardiac Resynchronization Therapy: In Control of Fusion Pacing

Fusion pacing, which exploits conduction via the intrinsic His-Purkinje system, forms the basis of recent cardiac resynchronization therapy (CRT) optimization algorithms. However, settings need to be constantly adjusted to accommodate for changes in AV conduction, and the algorithms are not always available (eg, depending on the device, in case of AV block or with atrial fibrillation). His-optimized cardiac resynchronization therapy (HOT-CRT), and left-bundle branch optimized cardiac resynchronization therapy (LOT-CRT) which combines conduction system pacing with ventricular fusion pacing, provide constant fusion with ventricular activation (irrespective of intrinsic AV conduction). These modalities provide promising treatment strategies for patients with heart failure, especially in those with chronic atrial fibrillation who require CRT (in whom the atrial port is usually plugged and can be used to connect the conduction system pacing lead).

Acute Hemodynamic Effects of Simultaneous and Sequential Multi-Point Pacing in Heart Failure Patients With an Expected Higher Rate of Sub-response to Cardiac Resynchronization Therapy: Results of Multicenter SYNSEQ Study

The aim of the SYNSEQ (Left Ventricular Synchronous vs. Sequential MultiSpot Pacing for CRT) study was to evaluate the acute hemodynamic response (AHR) of simultaneous (3P-MPP syn) or sequential (3P-MPP seq) multi-3-point-left-ventricular (LV) pacing vs. single point pacing (SPP) in a group of patients at risk of a suboptimal response to cardiac resynchronization therapy (CRT). Twenty five patients with myocardial scar or QRS ≤ 150 or the absence of LBBB (age: 66 ± 12 years, QRS: 159 ± 12 ms, NYHA class II/III, LVEF ≤ 35%) underwent acute hemodynamic assessment by LV + dP/dtmax with a variety of LV pacing configurations at an optimized AV delay. The change in LV + dP/dt max (%ΔLV + dP/dt max) with 3P-MPP syn (15.6%, 95% CI: 8.8%-22.5%) was neither statistically significantly different to 3P-MPP seq (11.8%, 95% CI: 7.6-16.0%) nor to SPP basal (11.5%, 95% CI:7.1-15.9%) or SPP mid (12.2%, 95% CI:7.9-16.5%), but higher than SPP apical (10.6%, 95% CI:5.3-15.9%, p = 0.03). AHR (defined as a %ΔLV + dP/dt max ≥ 10%) varied between pacing configurations: 36% (9/25) for SPP apical, 44% (11/25) for SPP basal, 54% (13/24) for SPP mid, 56% (14/25) for 3P-MPP syn and 48% (11/23) for 3P-MPP seq.Fifteen patients (15/25, 60%) had an AHR in at least one pacing configuration. AHR was observed in 10/13 (77%) patients with a LBBB but only in 5/12 (42%) patients with a non-LBBB (p = 0.11). To conclude, simultaneous or sequential multipoint pacing compared to single point pacing did not improve the acute hemodynamic effect in a suboptimal CRT response population.

Clinical Trial Registration

ClinicalTrials.gov, identifier: NCT02914457.