Comparison of De Novo versus Upgrade Cardiac Resynchronization Therapy; Focused on the Upgrade for Pacing-Induced Cardiomyopathy

Comparison of de novo implantation vs. upgrade cardiac resynchronisation therapy: a multicentre experience

BACKGROUND

The clinical safety and consequences of upgrade procedures compared with de novo cardiac resynchronisation therapy (CRT) implantation in heart failure remain unclear. The present study aimed to assess clinical and procedural consequences of patients undergoing CRT upgrade as compared to de novo CRT implantations.

METHODS

In this prospective cohort study, two subgroups were considered as the study population as (1) de novo group that CRT was considered on optimised medical treatment with heart failure of NYHA functional class from II to IV, left ventricular ejection fraction (LVEF) of ≤35%, and QRS width of >130 ms and (2) upgrade group including the patients with previously implantable cardioverter defibrillator (ICD) with the indications for upgrading to CRT. The two groups were compared regarding the changes in clinical outcome and echocardiography parameters.

RESULTS

The procedure was successful in 95.9% of patients who underwent CRT upgrade and 100% of those who underwent de novo CRT implantation. It showed a significant improvement in LVEF, severity of mitral regurgitation and NYHA functional classification, without any difference between the two study groups. Overall procedural related complications were reported in 10.8% and 3.8% (p = .093) and cardiac death in 5.4% and 2.5% (p = .360), respectively, with no overall difference in postoperative outcome between the two groups.

CONCLUSIONS

Upgrading to CRT is a safe and effective procedure regarding improvement of functional class, left ventricular function status and post-procedural outcome.

Beneficial effects of upgrading to His-Purkinje system pacing in patients with pacing-induced cardiomyopathy: a systematic review and meta-analysis

Background

The purpose of this study was to evaluate the effectiveness of His-Purkinje system pacing (HPSP) in the management of patients with pace-induced cardiomyopathy (PICM).

Methods

PubMed, Embase, Web of Science, and the Cochrane Library were searched comprehensively to collect related studies published from the inception of databases to June 1, 2022. R 4.04 software, including the Metafor package, matrix package, and the Meta package, was utilized to conduct the singe-arm meta-analysis. The methodology index for non-randomized studies (MINORS) was used to assess the methodological quality of the included studies.

Results

A total of seven studies were included, involving 164 PICM patients. The meta-analysis showed that HPSP ameliorated the left ventricular ejection fraction (LVEF) by 13.41% (95% CI [11.21-15.61]), improved the New York Heart Association (NYHA) classification by 1.02 (95% CI [-1.41 to -0.63]), and shortened the QRS duration (QRSd) by 60.85 ms (95% CI [-63.94 to -57.75]), resulting in improved cardiac functions in PICM patients. Besides, HPSP reversed the ventricular remodeling, with a 32.46 ml (95% CI [-53.18 to -11.75]) decrease in left ventricular end systolic volume (LVESV) and a 5.93 mm (95% CI [-7.68 to -4.19]) decrease in left ventricular end-diastolic dimension (LVEDD). HPSP also showed stable electrical parameters of pacemakers, with a 0.07 V (95% CI [0.01-0.13]) increase in pacing threshold, a 0.02 mV (95% CI [-0.85 to 0.90]) increase in sensed R-wave amplitude, and a 31.12 Ω reduction in impedance (95% CI [-69.62 to 7.39]). Compared with LBBP, HBP improved LVEF by 13.28% (95% CI [-11.64 to 14.92]) vs 14.43% (95% CI [-13.01 to 15.85]), ameliorated NHYA classification by 1.18 (95% CI [-1.97 to -0.39]) vs 0.95 (95% CI [-1.33 to -0.58]), shortened QRSd by 63.16 ms (95% CI [-67.00 to -59.32]) vs 57.98 ms (95% CI [-62.52 to -53.25]), and decreased LVEDD by 4.12 mm (95% CI [-5.79 to -2.45]) vs 6.26 mm (95% CI [-62.52 to -53.25]). The electrical parameters of the pacemaker were stable in both groups.

Conclusions

This meta-analysis showed that HPSP could significantly improve cardiac function, promote reverse remodeling, and provide stable electrical parameters of pacemakers for PICM patients.

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

Background

Pacing-induced cardiomyopathy (PICM) is an important cause of heart failure in patients with a right ventricular pacing burden. Recent evidence suggests that an upgrade to cardiac resynchronization therapy (CRT) may confer benefit in PICM.

Objective

To assess the extent and identify predictors of improvement following upgrade to CRT in patients with PICM.

Methods

We retrospectively analyzed 43 patients undergoing CRT upgrade for PICM over the 10-year period of 2011 to 2021 at our center. All patients with PICM who underwent device upgrade from a dual- or single-chamber ventricular pacemaker to CRT were included. PICM was defined as a decrease of ≥10% in left ventricular ejection fraction (LVEF), resulting in an LVEF <50% among patients with ≥20% Right ventricular pacing burden without an alternative cause for cardiomyopathy.

Results

LVEF significantly improved from 28.7% preupgrade to 44.3% post-CRT upgrade (P < .01). Of 37 patients with severe LV dysfunction, 34 (91.9%) improved to an LVEF >35% and 13 (35.1%) improved to an LVEF >50%. The LV end-diastolic diameter decreased from 5.9 cm preupgrade to 5.4 cm postupgrade (P < .01). Using linear regression, angiotensin-converting enzyme inhibitor or angiotensin receptor blocker use was associated with significant LVEF improvement (+7.21%, P = .05). We observed a low rate of complications, and 1 in 4 CRT upgrades required venoplasty (n = 10 of 43, 23.3%).

Conclusion

We provide further evidence for the benefit of CRT upgrade in the management of patients with PICM.

Upgrading right ventricular pacemakers to biventricular pacing or conduction system pacing: a systematic review and meta-analysis

Guidelines recommend patients undergoing a first pacemaker implant who have even mild left ventricular (LV) impairment should receive biventricular or conduction system pacing (CSP). There is no corresponding recommendation for patients who already have a pacemaker. We conducted a meta-analysis of randomized controlled trials (RCTs) and observational studies assessing device upgrades. The primary outcome was the echocardiographic change in LV ejection fraction (LVEF). Six RCTs (randomizing 161 patients) and 47 observational studies (2644 patients) assessing the efficacy of upgrade to biventricular pacing were eligible for analysis. Eight observational studies recruiting 217 patients of CSP upgrade were also eligible. Fourteen additional studies contributed data on complications (25 412 patients). Randomized controlled trials of biventricular pacing upgrade showed LVEF improvement of +8.4% from 35.5% and observational studies: +8.4% from 25.7%. Observational studies of left bundle branch area pacing upgrade showed +11.1% improvement from 39.0% and observational studies of His bundle pacing upgrade showed +12.7% improvement from 36.0%. New York Heart Association class decreased by -0.4, -0.8, -1.0, and -1.2, respectively. Randomized controlled trials of biventricular upgrade found improvement in Minnesota Heart Failure Score (-6.9 points) and peak oxygen uptake (+1.1 mL/kg/min). This was also seen in observational studies of biventricular upgrades (-19.67 points and +2.63 mL/kg/min, respectively). In studies of the biventricular upgrade, complication rates averaged 2% for pneumothorax, 1.4% for tamponade, and 3.7% for infection over 24 months of mean follow-up. Lead-related complications occurred in 3.3% of biventricular upgrades and 1.8% of CSP upgrades. Randomized controlled trials show significant physiological and symptomatic benefits of upgrading pacemakers to biventricular pacing. Observational studies show similar effects between biventricular pacing upgrade and CSP upgrade.

Device treatment of heart failure

Background: The incidence of heart failure (HF) is rapidly increasing, introducing a significant burden and challenges in clinical practice. Non-pharmacological cardiac device therapy has been established as an essential component of optimal HF management, particularly for the prevention of sudden cardiac death and the improvement of HF symptoms, left ventricular (LV) systolic function, quality of life, and eventually survival.Current Concepts: Cardiac resynchronization therapy (CRT) can correct atrioventricular or inter/intraventricular dyssynchrony, thereby improving LV systolic function. Recently, the concept of CRT is being expanded, including His bundle (HB), HB-optimized LV, left bundle branch (LBB), and LBB optimized LV pacing CRTs. Newly introduced CRT approaches by stimulating the cardiac conduction system are expected to correct dyssynchrony better and consequently exhibit better CRT outcomes than the conventional biventricular pacing CRT. The current versions of implantable cardioverter-defibrillators (ICDs) or CRT devices can continuously monitor multiple biosignals. CRT/ICD can calculate a single index by combining these multiple bio-signal data for early detection of HF aggravation. Recently, subcutaneous and transvenous ICDs showed comparable safety and efficacy in HF patients. In drug-refractory HF patients without LV dyssynchrony, cardiac contractility modulation therapy provides some promising results.Discussion and Conclusion: Recent technological advancements have improved the efficacy and safety of cardiac device therapy. Therefore, cardiac device therapy should be used more actively to manage HF patients better.

Pacemaker Induced Cardiomyopathy: An Overview of Current Literature

Pacemaker induced cardiomyopathy (PICM) is commonly defined as a reduction in left ventricular (LV) function in the setting of right ventricular (RV) pacing. This condition may be associated with the onset of clinical heart failure in those affected. Recent studies have focused on potential methods of identifying patients at risk of this condition, in addition to hypothesizing the most efficacious ways to manage these patients. Newer pacing options, such as His bundle pacing, may avoid the onset of PICM entirely.

Changes in cardiac conduction time following cardiac resynchronization therapy: rationale and design of the RECOVER study

BACKGROUND

It has been known that ventricular conduction delays play a key role in the cardiac resynchronization therapy (CRT) response of patients with advanced heart failure (HF). However, no study to our knowledge has yet evaluated the serial changes in conduction times measured between different electrodes of CRT devices.

METHODS AND RESULTS

The Reduction or Extension of Conduction Time with Ventricular Electromechanical Remodeling (RECOVER) study (NCT04397224) was designed to investigate serial changes in interelectrode conduction times and to elucidate their prognostic value. We plan to enroll 100 patients implanted with CRT systems with endocardial quadripolar left ventricular leads. Patients will be scheduled for follow-up every 3 months over a period of 2 years, where they will undergo measurement of interelectrode conduction times to evaluate their serial changes. The primary outcome of the RECOVER study is the correlation between the degree of conduction time changes and the CRT response as defined by echocardiography. The time course and prognostic value of the serial changes in conduction times will be investigated as well.

CONCLUSION

The RECOVER study is investigating whether serial changes in interelectrode conduction times can be useful parameters in predicting the CRT response or detecting worsening HF at an early stage.

The therapeutic effects of upgrade to cardiac resynchronization therapy in pacing-induced cardiomyopathy or chronic right ventricular pacing patients: a meta-analysis

Pacing-induced cardiomyopathy (PICM) or heart failure accompanied with chronic right ventricular pacing (CRVP-HF) has no established treatments. We aimed to carry out a meta-analysis of published studies about the therapeutic effects of the upgrade to cardiac resynchronization therapy (CRT) in patients of PICM/CRVP-HF. The PUBMED, EMBASE, MEDLINE, OVID databases, and Cochrane Library were systemically searched for relevant publications. Data about the improvements of left ventricular ejection fraction (LVEF), NYHA functional class (NYHA-FC), and the CRT response rate was extracted and synthesized. Mean difference (MD), odds ratio, and standard mean difference (SMD) with 95% confidence interval (CI) were calculated as the effect size by both fixed and random effect models. We included sixteen studies (four about PICM and twelve about CRVP-HF). The total sample size of PICM/CRVP-HF patients was 924. Upgrade to CRT improved the LVEF by 10.87% (95%CI, 8.90 to 12.84%) and reduce the NYHA-FC by around one class (MD, -1.25; 95%CI, -1.43 to -1.06) in PICM/CRVP-HF patients overall. Upgrade to CRT seemed to improve LVEF no less than de-novo CRT (SMD 0.24; 95%CI 0.05 to 0.43; P < 0.05). This meta-analysis suggested that upgrade CRT could improve the cardiac function in PICM/CRVP-HF patients. This strategy may be considered in these patients but require more evidence about the efficacy and procedure-related complications from prospective studies or randomized controlled trials.

Cardiac resynchronization therapy in New York Heart Association class-IV patients dependent on intravenous drugs or invasive supportive treatments

Aims

We sought to evaluate the effectiveness of cardiac resynchronization therapy (CRT) in far‐advanced heart failure (FA‐HF) patients with New York Heart Association (NYHA) class‐IV status and dependency on intravenous drugs (IVDs) and/or invasive supportive treatments (ISTs).

Methods and results

Among 305 patients who underwent CRT implantation between October 2005 to December 2019, we identified 17 FA‐HF patients with NYHA class‐IV status and dependency on IVDs (inotropes, diuretics, vasopressors, or vasodilators) and/or ISTs (extracorporeal membranous oxygenator or continuous renal replacement therapy). All patients (median age = 68.7 years, non‐ischaemic cardiomyopathy = 15) remained dependent on several IVDs (2.2 ± 1.3 per patient) and/or ISTs for 11.3 ± 7.8 days due to multiple tapering failure (4.3 ± 3.2 per patient) before CRT implantation. However, 14 (82%) patients were successfully weaned from IVDs/ISTs within 5.2 ± 5.3 days following CRT, and 12 (71%) stayed alive for more than 1 year free of ventricular assist device or heart transplantation with symptom improvement (≥1 NYHA class) and a reduced annual HF hospitalization rate (P = 0.002). Considerable improvements in ventricular systolic function (P = 0.004) and volumetric reverse remodelling (P = 0.007) were noticed during the long‐term follow‐up period (35 ± 15 months post‐CRT). The ventricular assist device/heart transplantation/death‐free survival rate post‐CRT was 71% and 65% at 1 and 3 years, respectively.

Conclusions

Cardiac resynchronization therapy implantation may be a feasible treatment that can offer short‐term and long‐term clinical benefits for NYHA class‐IV FA‐HF patients who are dependent on IVDs/ISTs. When considering treatment options, CRT should not be prematurely excluded solely based on a patient's dependency on IVDs/ISTs without first attempting to identify favourable CRT response factors.

Efficacy of Cardiac Resynchronization Therapy Using Automated Dynamic Optimization and Left Ventricular-only Pacing

BACKGROUND

Although device-based optimization has been developed to overcome the limitations of conventional optimization methods in cardiac resynchronization therapy (CRT), few real-world data supports the results of clinical trials that showed the efficacy of automatic optimization algorithms. We investigated whether CRT using the adaptive CRT algorithm is comparable to non-adaptive biventricular (BiV) pacing optimized with electrocardiogram or echocardiography-based methods.

METHODS

Consecutive 155 CRT patients were categorized into 3 groups according to the optimization methods: non-adaptive BiV (n = 129), adaptive BiV (n = 11), and adaptive left ventricular (LV) pacing (n = 15) groups. Additionally, a subgroup of patients (n = 59) with normal PR interval and left bundle branch block (LBBB) was selected from the non-adaptive BiV group. The primary outcomes included cardiac death, heart transplantation, LV assist device implantation, and heart failure admission. Secondary outcomes were electromechanical reverse remodeling and responder rates at 6 months after CRT.

RESULTS

During a median 27.5-month follow-up, there was no significant difference in primary outcomes among the 3 groups. However, there was a trend toward better outcomes in the adaptive LV group compared to the other groups. In a more rigorous comparisons among the patients with normal PR interval and LBBB, similar patterns were still observed.

CONCLUSION

In our first Asian-Pacific real-world data, automated dynamic CRT optimization showed comparable efficacy to conventional methods regarding clinical outcomes and electromechanical remodeling.

Clinical features, predictors, and long-term prognosis of pacing-induced cardiomyopathy

AIMS

We investigated the clinical features, predictors, and long-term prognosis of pacing-induced cardiomyopathy (PiCM).

METHODS AND RESULTS

From a retrospective analysis of 1418 consecutive pacemaker patients, 618 were found to have a preserved baseline left ventricular ejection fraction (LVEF), follow-up echocardiographic data, and no history of heart failure (HF). PiCM was defined as a reduction in LVEF (< 50%) along with either (i) a ≥ 10% decrease in LVEF, or (ii) new-onset regional wall motion abnormality unrelated to coronary artery disease. PiCM occurred in 87 of 618 patients (14.1%), with a decrease in mean LVEF from 60.5% to 40.1%. The median time to PiCM was 4.7 years. Baseline left bundle branch block, wider paced QRS duration (≥ 155 ms), and higher ventricular pacing percentage (≥ 86%) were identified as independent predictors of PiCM in multivariate logistic regression analysis. The risk of PiCM increased gradually with the number of identified predictors, becoming more significant in the presence of two or more predictors (P < 0.001). During the entire follow-up (median 7.2 years), the risk of all-cause death or HF admission was significantly higher in patients with PiCM compared to those without PiCM (38.3% vs. 54.0%, adjusted hazard ratio 2.93; 95% confidence interval 1.82-4.72; P < 0.001).

CONCLUSION

Pacing-induced cardiomyopathy patients showed a worse long-term prognosis than those without PiCM. Therefore, patients with multiple risk factors of PiCM should be monitored carefully even if their left ventricular systolic function is preserved initially. A timely upgrade to a biventricular or His-bundle pacing device needs to be considered in patients with PiCM.

Outcomes of cardiac resynchronization therapy in patients with atrial fibrillation accompanied by slow ventricular response

It remains unclear as to whether cardiac resynchronization therapy (CRT) would be as effective in patients with atrial fibrillation (AF) accompanied by slow ventricular response (AF-SVR, < 60 beats/min) as in those with sinus rhythm (SR). Echocardiographic reverse remodeling was compared between AF-SVR patients (n = 17) and those with SR (n = 88) at six months and 12 months after CRT treatment. We also evaluated the changes in QRS duration; New York Heart Association (NYHA) functional class; and long-term composite clinical outcomes including cardiac death, heart transplantation, and heart failure (HF)-related hospitalization. Left ventricular pacing sites and biventricular pacing percentages were not significantly different between the AF-SVR and SR groups. However, heart rate increase after CRT was significantly greater in the AF-SVR group than in the SR group (P < 0.001). At six and 12 months postoperation, both groups showed a comparable improvement in NYHA class; QRS narrowing; and echocardiographic variables including left ventricular end-systolic volume, left ventricular ejection fraction, and left atrial volume index. Over the median follow-up duration of 1.6 (interquartile range: 0.8–2.2) years, no significant between-group differences were observed regarding the rates of long-term composite clinical events (35% versus 24%; hazard ratio: 1.71; 95% confidence interval: 0.23–12.48; P = 0.60). CRT implantation provided comparable beneficial effects for patients with AF-SVR as compared with those with SR, by correcting electrical dyssynchrony and increasing biventricular pacing rate, in terms of QRS narrowing, symptom improvement, ventricular reverse remodeling, and long-term clinical outcomes.