Improved prognosis after cardiac resynchronization therapy over a decade

AIMS

The past decade has seen an increased delivery of cardiac resynchronization therapy (CRT) for patients with heart failure (HF). We explored whether clinical outcomes after CRT have changed from the perspective of an entire public healthcare system.

METHODS AND RESULTS

A national database covering the population of England (56.3 million in 2019) was used to explore clinical outcomes after CRT from 2010 to 2019. A total of 64 698 consecutive patients (age 71.4 ± 11.7 years; 74.8% male) underwent CRT-defibrillation [n = 32 313 (49.7%)] or CRT-pacing [n = 32 655 (50.3%)] implantation. From 2010-2011 to 2018-2019, there was a 76% increase in CRT implantations. During the same period, the proportion of patients with hypertension (59.6-73.4%), diabetes (26.5-30.8%), and chronic kidney disease (8.62-22.5%) increased, as did the Charlson comorbidity index (CCI ≥ 3 from 20.0% to 25.1%) (all P < 0.001). Total mortality decreased at 30 days (1.43-1.09%) and 1 year (9.51-8.13%) after implantation (both P < 0.001). At 2 years, total mortality [hazard ratio (HR): 0.72; 95% confidence interval (CI) 0.69-0.76] and total mortality or HF hospitalization (HR: 0.59; 95% CI 0.57-0.62) decreased from 2010-2011 to 2018-2019, after correction for age, race, sex, device type (CRT-defibrillation or pacing), comorbidities (hypertension, diabetes, chronic kidney disease, and myocardial infarction), or the CCI (HR: 0.81; 95% CI 0.77-0.85).

CONCLUSIONS

From the perspective of an entire public health system, survival has improved and HF hospitalizations have decreased after CRT implantation over the past decade. This prognostic improvement has occurred despite an increasing comorbidity burden.

Cardiac resynchronization therapy in adults with structural congenital heart disease and chronic heart failure

AIMS

Evidence for CRT in adults with congenital heart disease (ACHD) and chronic heart failure is limited, with recommendations for its use extrapolated from the population with structurally normal hearts. This retrospective observational study investigates the efficacy of CRT in this heterogenous group, discussing factors predicting response to CRT.

METHODS

Twenty-seven patients with structural ACHD who underwent CRT insertion or upgrade at a tertiary center in the United Kingdom were retrospectively studied. The primary outcome measure was clinical response to CRT, defined as improvement of NYHA class and/or improvement in systemic ventricular ejection fraction by one category. Secondary outcomes included change in QRS duration and adverse events.

RESULTS

Thirty-seven percent of patients had a systemic right ventricle (sRV). RBBB was the commonest baseline QRS morphology (40.7%) despite this being an unfavorable characteristic for CRT. Overall, positive response to CRT was demonstrated in 18 patients (66.7%). NYHA class improved in 55.5% following CRT (p = .001) and 40.7% showed improvement in systemic ventricular ejection fraction (p = .118). There were no baseline characteristics that predicted response to CRT, and electrocardiographic measures such as QRS shortening post-CRT was not associated with positive response. Good response rates (60.0%) were demonstrated in those with sRV.

CONCLUSION

CRT is efficacious in structural ACHD including in those who do not meet conventional criteria. Extrapolation of recommendations from adults with structurally normal hearts may be inappropriate. Future research should focus on improving patient selection for CRT, for example using techniques to better quantify mechanical dysynchrony and intra-procedural electrical activation mapping in these complex patients.

Timing of cardiac resynchronization therapy implantation

AIMS

The optimum timing of cardiac resynchronization therapy (CRT) implantation is unknown. We explored long-term outcomes after CRT in relation to the time interval from a first heart failure hospitalization (HFH) to device implantation.

METHODS AND RESULTS

A database covering the population of England (56.3 million in 2019) was used to quantify clinical outcomes after CRT implantation in relation to first HFHs. From 2010 to 2019, 64 968 patients [age: 71.4 ± 11.7 years; 48 606 (74.8%) male] underwent CRT implantation, 57% in the absence of a previous HFH, 12.9% during the first HFH, and 30.1% after ≥1 HFH. Over 4.54 (2.80-6.71) years [median (interquartile range); 272 989 person-years], the time in years from the first HFH to CRT implantation was associated with a higher risk of total mortality [hazard ratio (HR); 95% confidence intervals (95% CI)] (1.15; 95% CI 1.14-1.16, HFH (HR: 1.26; 95% CI 1.24-1.28), and the combined endpoint of total mortality or HFH (HR: 1.19; 95% CI 1.27-1.20) than CRT in patients with no previous HFHs, after co-variate adjustment. Total mortality (HR: 1.67), HFH (HR: 2.63), and total mortality or HFH (HR: 1.92) (all P < 0.001) were highest in patients undergoing CRT ≥2 years after the first HFH.

CONCLUSION

In this study of a healthcare system covering an entire nation, delays from a first HFH to CRT implantation were associated with progressively worse long-term clinical outcomes. The best clinical outcomes were observed in patients with no previous HFH and in those undergoing CRT implantation during the first HFH.

CONDENSED ABSTRACT

The optimum timing of CRT implantation is unknown. In this study of 64 968 consecutive patients, delays from a first heart failure hospitalization (HFH) to CRT implantation were associated with progressively worse long-term clinical outcomes. Each year from a first HFH to CRT implantation was associated with a 21% higher risk of total mortality and a 34% higher risk of HFH. The best outcomes after CRT were observed in patients with no previous HFHs and in those undergoing implantation during their first HFH.

Core protocol for the adaptive Platform Trial In COVID-19 Vaccine priming and BOOsting (PICOBOO)

BACKGROUND

The need for coronavirus 2019 (COVID-19) vaccination in different age groups and populations is a subject of great uncertainty and an ongoing global debate. Critical knowledge gaps regarding COVID-19 vaccination include the duration of protection offered by different priming and booster vaccination regimens in different populations, including homologous or heterologous schedules; how vaccination impacts key elements of the immune system; how this is modified by prior or subsequent exposure to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and future variants; and how immune responses correlate with protection against infection and disease, including antibodies and effector and T cell central memory.

METHODS

The Platform Trial In COVID-19 priming and BOOsting (PICOBOO) is a multi-site, multi-arm, Bayesian, adaptive, randomised controlled platform trial. PICOBOO will expeditiously generate and translate high-quality evidence of the immunogenicity, reactogenicity and cross-protection of different COVID-19 priming and booster vaccination strategies against SARS-CoV-2 and its variants/subvariants, specific to the Australian context. While the platform is designed to be vaccine agnostic, participants will be randomised to one of three vaccines at trial commencement, including Pfizer's Comirnaty, Moderna's Spikevax or Novavax's Nuvaxovid COVID-19 vaccine. The protocol structure specifying PICOBOO is modular and hierarchical. Here, we describe the Core Protocol, which outlines the trial processes applicable to all study participants included in the platform trial.

DISCUSSION

PICOBOO is the first adaptive platform trial evaluating different COVID-19 priming and booster vaccination strategies in Australia, and one of the few established internationally, that is designed to generate high-quality evidence to inform immunisation practice and policy. The modular, hierarchical protocol structure is intended to standardise outcomes, endpoints, data collection and other study processes for nested substudies included in the trial platform and to minimise duplication. It is anticipated that this flexible trial structure will enable investigators to respond with agility to new research questions as they arise, such as the utility of new vaccines (such as bivalent, or SARS-CoV-2 variant-specific vaccines) as they become available for use.

TRIAL REGISTRATION

Australian and New Zealand Clinical Trials Registry ACTRN12622000238774. Registered on 10 February 2022.

Right ventricular function and long-term clinical outcomes after cardiac resynchronization therapy: A cardiovascular magnetic resonance study

BACKGROUND

Right ventricular (RV) dysfunction has been linked to a poor response to cardiac resynchronization therapy (CRT). We sought to determine whether cardiovascular magnetic resonance (CMR)-derived measures of RV function influence clinical outcomes after CRT.

METHODS

In this retrospective study, we used cardiovascular magnetic resonance (CMR) to assess pre-implant RV volumes and RV ejection fraction (RVEF) in relation to clinical outcomes after CRT implantation.

RESULTS

Among 243 patients (age: 70.3 ± 10.8 years [mean ±. SD]; 68.7% male; 121 [49.8%]) with ischemic cardiomyopathy and 122 (50.2%) with non-ischemic cardiomyopathy, 141 (58%) after CRT-defibrillation and 102 (42%) after CRT-pacing, 101 (41.6.0%) patients died, 61 (25.1%) from cardiac causes and 24 (9.88%) from non-cardiac causes, over 5.87 years (median; interquartile range: 4.35-7.73). Two (0.82%) patients underwent cardiac transplantation and 4 (1.64%) had a left ventricular assist device. A total of 41 (16.9%) met the composite endpoint of sudden cardiac death, ventricular tachycardia or ventricular fibrillation. In univariate analyses, no measure of RV function was associated with total mortality or the arrhythmic endpoint. RVEF was associated with cardiac mortality on univariate analyses (HR per 10%: 0.82, 95% CI 0.70-0.96), but not on multivariate analyses that included left ventricular ejection fraction.

CONCLUSIONS

There is no relationship between measures of RV function, such as RV volumes and RVEF, and the long-term clinical outcome of CRT. These findings indicate that such measures should not be considered in patient selection. This article is protected by copyright. All rights reserved.

Myocardial fibrosis predicts ventricular arrhythmias and sudden death after cardiac electronic device implantation

Funding Acknowledgements

Type of funding sources: Private grant(s) and/or Sponsorship. Main funding source(s): Unrestricted educational grants

Background

Increasing evidence supports a link between myocardial fibrosis (MF) and ventricular arrhythmias. We sought to determine whether presence of MF on visual assessment (MFVA) and gray zone fibrosis (GZF) mass predicts SCD and ventricular fibrillation / sustained ventricular tachycardia after cardiac implantable electronic device (CIED) implantation.

Methods

In this prospective study, total fibrosis and GZF mass, quantified using cardiovascular magnetic resonance, was assessed in relation to the primary endpoint of sudden cardiac death (SCD) and the secondary, arrhythmic endpoint of SCD or ventricular arrhythmias after CIED implantation.

Results

Among 700 patients (age 68.0 ± 12.0yrs [mean ± SD]), 27 (3.85%) experienced a SCD and 121 (17.3%) met the arrhythmic endpoint over 6.93 yrs (median; interquartile range 5.82-9.32). MFVA predicted SCD (hazard ratio [HR]: HR:26.3 [95% confidence interval [CI] 3.70-3337]; negative predictive value: 100%). In competing risks analyses, MFVA also predicted the arrhythmic endpoint (subdistribution [sHR]: 19.9 [95% CI 6.40-61.9]; negative predictive value:98.6%). Compared with no MFVA, a GZF mass measured with the 5SD method (GZF5SD) &gt; 17 g was associated with highest risk of SCD (HR: 44.6;95% CI 6.12-5685) and the arrhythmic endpoint (sHR: 30.3 [95% CI 9.60-95.8]). Adding GZF5SD mass to MFVA led to reclassification of 39% for SCD and 50.2% for the arrhythmic endpoint. In contrast, LVEF did not predict either endpoint.

Conclusions

In CIED recipients, MFVA excluded patients at risk of SCD and virtually excluded ventricular arrhythmias. Quantified GZF5SD mass added predictive value in relation to SCD and the arrhythmic endpoint.

Myocardial Fibrosis Predicts Ventricular Arrhythmias and Sudden Death After Cardiac Electronic Device Implantation

BACKGROUND

Increasing evidence supports a link between myocardial fibrosis (MF) and ventricular arrhythmias.

OBJECTIVES

The purpose of this study was to determine whether presence of myocardial fibrosis on visual assessment (MFVA) and gray zone fibrosis (GZF) mass predicts sudden cardiac death (SCD) and ventricular fibrillation/sustained ventricular tachycardia after cardiac implantable electronic device (CIED) implantation.

METHODS

In this prospective study, total fibrosis and GZF mass, quantified using cardiovascular magnetic resonance, was assessed in relation to the primary endpoint of SCD and the secondary, arrhythmic endpoint of SCD or ventricular arrhythmias after CIED implantation.

RESULTS

Among 700 patients (age 68.0 ± 12.0 years), 27 (3.85%) experienced a SCD and 121 (17.3%) met the arrhythmic endpoint over median 6.93 years (IQR: 5.82-9.32 years). MFVA predicted SCD (HR: 26.3; 95% CI: 3.7-3,337; negative predictive value: 100%). In competing risk analyses, MFVA also predicted the arrhythmic endpoint (subdistribution HR: 19.9; 95% CI: 6.4-61.9; negative predictive value: 98.6%). Compared with no MFVA, a GZF mass measured with the 5SD method (GZF5SD) >17 g was associated with highest risk of SCD (HR: 44.6; 95% CI: 6.12-5,685) and the arrhythmic endpoint (subdistribution HR: 30.3; 95% CI: 9.6-95.8). Adding GZF5SD mass to MFVA led to reclassification of 39% for SCD and 50.2% for the arrhythmic endpoint. In contrast, LVEF did not predict either endpoint.

CONCLUSIONS

In CIED recipients, MFVA excluded patients at risk of SCD and virtually excluded ventricular arrhythmias. Quantified GZF5SD mass added predictive value in relation to SCD and the arrhythmic endpoint.

Greyzone myocardial fibrosis and ventricular arrhythmias in patients with a left ventricular ejection fraction >35

AIMS

To determine whether myocardial fibrosis and greyzone fibrosis (GZF) on cardiovascular magnetic resonance (CMR) is associated with ventricular arrhythmias in patients with coronary artery disease (CAD) and a left ventricular ejection fraction (LVEF) >35%.

METHODS AND RESULTS

In this retrospective study of CAD patients, GZF mass using the 3SD method (GZF3SD) and total fibrosis mass using the 2SD method (TF2SD) on CMR were assessed in relation to the primary, combined endpoint of sudden cardiac death, ventricular tachycardia, ventricular fibrillation, or resuscitated cardiac arrest. Among 701 patients [age: 65.8 ± 12.3 years (mean ± SD)], 28 (3.99%) patients met the primary endpoint over 5.91 years (median; interquartile range 4.42-7.64). In competing risks analysis, a GZF3SD mass ≥5.0 g was strongly associated with the primary endpoint [subdistribution hazard ratio (sHR): 17.4 (95% confidence interval, CI 6.64-45.5); area under receiver operator characteristic curve (AUC): 0.85, P < 0.001]. A weaker association was observed for TF2SD mass ≥23 g [sHR 10.4 (95% CI 4.22-25.8); AUC: 0.80, P < 0.001]. The range of sHRs for GZF3SD mass (1-527) was wider than for TF2SD mass (1-37.6).

CONCLUSIONS

In CAD patients with an LVEF >35%, GZF3SD mass was strongly associated with the arrhythmic endpoint. These findings hold promise for its use in identifying patients with CAD and an LVEF >35% at risk of arrhythmic events.

Endocardial pacing is not haemodynamically superior to trans-coronary sinus epicardial pacing in cardiac resynchronization therapy: the Endo-Epi CRT study

Funding Acknowledgements

Type of funding sources: Private grant(s) and/or Sponsorship. Main funding source(s): Medtronic

Background

Cardiac resynchronization therapy (CRT) conventionally involves trans-coronary sinus, epicardial left ventricular (LV) pacing. Some studies have suggested that endocardial LV pacing may be superior to epicardial LV pacing.

Objectives

To compare the acute haemodynamic effects of CRT when delivered from endocardial (Endo-CRT) and epicardial LV stimulation sites (Epi-CRT).

Methods and results

Sixteen CRT recipients (aged 70.4 ± 10.1 years [mean ± SD], 62.5% male, QRS: 156.5 ± 16.1 ms, LBBB in 13 [81.3%]) in sinus rhythm underwent intra-procedural measurements of the rate of rise of LV pressure (dP/dtmax) during Endo- and Epi-CRT (RADI pressure wire). Epi-CRT was delivered in basal, mid and apical positions. The Endo-CRT pacing site was chosen using iterative, biplane fluoroscopic views, to target the same position as the Epi-CRT site on the endocardium (see Figure A). Compared to AAI pacing (10 beats per minute above intrinsic rate), both Endo-CRT and Epi-CRT led to an increase in LV dP/dtmax (6.52 ± 8.90% and 6.15 ± 7.97% respectively, both p &lt; 0.001). There were no significant differences in the change in LV dP/dtmax (ΔLV dP/dtmax) between Endo-CRT and Epi-CRT at basal (p = 0.54), mid (p = 0.78) or apical LV stimulation sites (p = 0.12) [Figure B].

Conclusions

Endo-CRT is not haemodynamically superior to Epi-CRT. Abstract Figure.

Grayzone myocardial fibrosis and ventricular arrhythmias in patients with a left ventricular ejection fraction greater than 35%

Funding Acknowledgements

Type of funding sources: None.

BACKGROUND Clinical guidelines adopt LVEF cut-offs &lt;30 or &lt;35% as an indication for implantable cardioverter defibrillator (ICD) therapy. Most patients succumbing to sudden cardiac death (SCD), however, have a LVEF≥35%.

OBJECTIVES To determine whether myocardial fibrosis (MF) and grayzone fibrosis (GZF) on cardiovascular magnetic resonance (CMR) is associated with ventricular arrhythmias in patients with coronary artery disease (CAD) and a LVEF≥35%.

METHODS In this retrospective study of CAD patients, GZF mass using the 3SD method (GZF3SD) and total fibrosis mass using the 2SD method (TF2SD) on CMR were assessed in relation to the primary, combined endpoint of SCD, ventricular tachycardia, ventricular fibrillation or resuscitated cardiac arrest.

RESULTS Among 701 patients (age: 65.8 ± 12.3 yrs [mean ± SD]), 28 (3.99%) patients met the primary endpoint over 5.91 years (median; interquartile range 4.42-7.64). In competing risks analysis, a GZF3SD mass ≥ 5.0 g was strongly associated with the primary endpoint (subdistribution hazard ratio [sHR]: 17.4 [95% CI 6.64-45.5]); area under receiver operator characteristic curve [AUC]: 0.85, p &lt; 0.001). A weaker association was observed for TF2SD mass ≥ 23 g (HR: 10.4 [95% CI 4.22-25.8]; AUC: 0.80, p &lt; 0.001). The range of sHRs for GZF3SD mass (1 to 526.6) was wider than for TF2SD mass (1 to 37.6).

CONCLUSIONS In CAD patients with a LVEF≥35%, GZF3SD mass was strongly associated with the arrhythmic endpoint. These findings hold promise for its use in identifying patients with CAD and a LVEF≥35% at risk of arrhythmic events. Abstract Figure.

Myocardial fibrosis as a predictor of sudden death in patients with coronary artery disease

Funding Acknowledgements

Type of funding sources: None.

BACKGROUND The ‘grayzone’ of myocardial fibrosis (GZF) on cardiovascular magnetic resonance may be a substrate for ventricular arrhythmias (VAs).

OBJECTIVES To determine whether GZF predicts SCD and VAs (ventricular fibrillation or sustained ventricular tachycardia) in patients with coronary artery disease (CAD) and a wide range of LVEFs.

METHODS In this retrospective study of CAD patients, myocardial fibrosis presence on visual assessment (MFVA) and GZF mass in patients with MFVA was assessed in relation to SCD and the composite, arrhythmic endpoint of SCD or VAs.

RESULTS Among 979 patients (age: 65.8 ± 12.3 yrs [mean ± SD]), 29(2.96%) suffered a SCD and 80(8.17%) met the arrhythmic endpoint over 5.82 years (median; interquartile range: 4.1-7.3). In the whole cohort, MFVA was strongly associated with SCD (hazard ratio [HR]:10.1, 95% CI 1.42-1278.9) and the arrhythmic endpoint (HR:28.0, 95% CI 4.07-3525.4). In competing risks analyses, associations between LVEF &lt; 35% and SCD (subdistribution HR [sHR]:2.99, 95% CI 1.42-6.31) and the arrhythmic endpoint (sHR:4.71, 95% CI 2.97-7.47) were weaker. In competing risks analyses of the MFVA subcohort (n = 832), GZF using the 3SD method (GZF3SD) &gt; 5.0 g was strongly associated with SCD (sHR:10.8, 95% CI 3.74-30.9) and the arrhythmic endpoint (sHR:7.40, 95% CI 4.29-12.8). Associations between LVEF &lt; 35% and SCD (sHR:2.62, 95% CI 1.24-5.52) and the arrhythmic endpoint (sHR:4.14, 95% CI 2.61-6.57) were weaker.

CONCLUSIONS In CAD patients, MFVA plus quantified GZF3SD mass was more strongly associated with SCD and VAs than LVEF. In selecting patients for implantable cardioverter defibrillators, assessment of MFVA followed by quantification of GZF3SD mass may be preferable to LVEF. Abstract Figure.

Accuracy of a point-of-care major crossmatch test and risk factors for major crossmatch incompatibility in cats

Major crossmatch testing can help identify immunologic incompatibilities between blood donors and recipients; however, there are limited studies describing the accuracy of point-of-care crossmatch tests. The first aim of this study was to determine if a gel-based, point-of-care major crossmatch method (GEL-CM), without antiglobulin-enhancement, could accurately detect compatible and incompatible donor-recipient pairings, using an antiglobulin-enhanced laboratory-based major crossmatch method (LAB-CM) as the reference standard. The second aim was to describe the incidence of, and risk factors for, major crossmatch incompatibility in cats. Nineteen previously-transfused cats and 32 transfusion-naïve cats, representing 132 unique donor-recipient pairings, were included in this study. Both LAB-CM and GEL-CM tests were performed for most parings. There was poor agreement between the LAB-CM and GEL-CM results (kappa = 0.111; 95% confidence interval [CI], -0.093 to 0.314). Transfusion-naïve cats had incompatibility rates of 3% and 6% using LAB-CM and GEL-CM, respectively; previously-transfused cats had incompatibility rates of 32% and 26% using LAB-CM and GEL-CM, respectively. History of previous transfusion was the only identified cat risk factor for an incompatible LAB-CM (odds ratio [OR], 31.0; 95% CI, 3.77-254.98; P = 0.0019) and GEL-CM (OR, 5.7; 95% CI, 1.72-19.20; P = 0.0054). Further studies are needed to determine if GEL-CM can detect clinically-relevant immunologic incompatibilities that would result in transfusion reactions. Major crossmatch testing is of greater importance in cats that have previously received a transfusion.

Diathermy-induced Ventricular Fibrillation

Diathermy is extensively used in patients for intracardiac device implant and extraction. While diathermy helps with adequate hemostasis, it may rarely be associated with fatal dysrhythmias. We report a case of diathermy-induced ventricular fibrillation during device extraction. The case highlights the importance and supports the involvement of a defibrillation facility during pacemaker revisions requiring diathermy.

Evaluation of Pirfenidone and Nintedanib in a Human Lung Model of Fibrogenesis

Introduction: Idiopathic pulmonary fibrosis (IPF) is a progressive, fatal lung disease with a poor prognosis and increasing incidence. Pirfenidone and nintedanib are the only approved treatments for IPF but have limited efficacy and their mechanisms of action are poorly understood. Here we have examined the effects of pirfenidone and nintedanib in a human model of lung fibrogenesis, and compared these with the putative anti-fibrotic compounds Lipoxin A4 (LXA4), and senicapoc, a K_Ca3.1 ion channel blocker. Methods: Early fibrosis was induced in cultured human lung parenchyma using TGFβ1 for 7 days, ± pirfenidone, nintedanib, or LXA4. Pro-fibrotic responses were examined by RT-PCR, immunohistochemistry and soluble collagen secretion. Results: Thirty six out of eighty four IPF and fibrosis-associated genes tested were significantly upregulated by TGFβ1 in human lung parenchyma with a ≥0.5 log2FC (n = 32). Nintedanib (n = 13) reduced the mRNA expression of 14 fibrosis-associated genes including MMPs (MMP1,-4,-13,-14), integrin α2, CXCR4 and PDGFB, but upregulated α-smooth muscle actin (αSMA). Pirfenidone only reduced mRNA expression for MMP3 and -13. Senicapoc (n = 11) previously attenuated the expression of 28 fibrosis-associated genes, including αSMA, several growth factors, collagen type III, and αV/β6 integrins. Pirfenidone and nintedanib significantly inhibited TGFβ1-induced fibroblast proliferation within the tissue, but unlike senicapoc, neither pirfenidone nor nintedanib prevented increases in tissue αSMA expression. LXA4 was ineffective. Conclusions: Pirfenidone and nintedanib demonstrate modest anti-fibrotic effects and provide a benchmark for anti-fibrotic activity of new drugs in human lung tissue. Based on these data, we predict that the K_Ca3.1 blocker senicapoc will show greater benefit than either of these licensed drugs in IPF.

Survival after cardiac resynchronization therapy: results from 50 084 implantations

Aims

Randomized controlled trials have shown that cardiac resynchronization therapy (CRT) prolongs survival in patients with heart failure. No studies have explored survival after CRT in relation to individuals in the general population (relative survival, RS). We sought to determine observed and RS after CRT in a nationwide cohort undergoing CRT.

Methods and results

A national administrative database was used to quantify observed mortality for patients undergoing CRT. Relative survival (RS) was quantified using life tables. In 50 084 patients [age 72.1 ± 11.6 years (mean ± standard deviation)] undergoing CRT with (CRT-D) (n = 25 273) or without (CRT-P) defibrillation (n = 24 811) over 8.8 years (median follow-up 2.7 years, interquartile range 1.3–4.8), expected survival decreased with age. Device type, male sex, ischaemic heart disease, diabetes, and chronic kidney disease predicted excess mortality. In multivariate analyses, excess mortality (analogue of RS) was lower after CRT-D than after CRT-P in all patients [adjusted hazard ratio (aHR) 0.80, 95% confidence interval (CI) 0.76–0.84] as well as in subgroups with (aHR 0.79, 95% CI 0.74–0.84) or without (aHR 0.82, 95% CI 0.74–0.91) ischaemic heart disease. A Charlson Comorbidity Index (CCI) ≥3 portended a higher excess mortality (aHR 3.04, 95% CI 2.76–3.34). Relative survival was higher in 2015–2017 than in 2009–2011 (aHR 0.64, 95% CI 0.59–0.69).

Conclusion

Reference RS data after CRT is presented. Sex, ischaemic heart disease, diabetes, chronic kidney disease, and CCI were major determinants of RS after CRT. CRT-D was associated with a higher RS than CRT-P in patients with or without ischaemic heart disease. Relative survival after CRT improved from 2009 to 2017.

Lapatinib plus Capecitabine versus Trastuzumab plus Capecitabine in the Treatment of Human Epidermal Growth Factor Receptor 2-positive Metastatic Breast Cancer with Central Nervous System Metastases for Patients Currently or Previously Treated with Trastuzumab (LANTERN): a Phase II Randomised Trial

AIMS

Brain (central nervous system; CNS) metastases occur in 30-50% of patients with human epidermal growth factor receptor 2 (HER2)-positive metastatic breast cancer (MBC). A substantive evidence base for treatment is lacking, but activity with lapatinib plus capecitabine (lap-cap) has been reported. We compared lap-cap with trastuzumab plus capecitabine (tras-cap) in patients with HER2-positive MBC with CNS metastases previously treated with trastuzumab.

MATERIALS AND METHODS

This open-label randomised phase II screening trial aimed to randomise 130 participants over 2 years to receive lap-cap or tras-cap. Eligible patients had HER2-positive MBC with newly diagnosed or recently progressed CNS metastases; previous, or current, treatment included: trastuzumab, a taxane or anthracycline and recent completion of local cranial therapy. The primary end point was time to progression of CNS metastases within the 24-week trial period. Secondary objectives included CNS response rate, progression-free survival, steroid use for CNS symptoms and feasibility of recruitment to a large phase III trial.

RESULTS

Between September 2011 and October 2013, 30 participants were randomised, 16 to lap-cap and 14 to tras-cap. Recruitment to a large phase III trial was determined not to be feasible. At 24 weeks, CNS disease progression was 41.8% (95% confidence interval 16.1-67.5%) in lap-cap and 41.2% (95% confidence interval 12.8-69.6%) in tras-cap arms; progression-free survival was 44.4% (95% confidence interval 18.1-70.8%) in lap-cap and 50.0% (95% confidence interval 20.9-79.1%) in tras-cap arms.

CONCLUSION

Poor recruitment confirmed that a larger phase III trial would not be feasible and prohibited a preliminary evaluation of the superiority of lap-cap over tras-cap. Descriptive statistics are presented to inform the limited evidence base and future study design.

Effect of QRS area reduction and myocardial scar on the hemodynamic response to cardiac resynchronization therapy

BACKGROUND

Vectorcardiographic QRS area (QRS_area) predicts clinical outcomes after cardiac resynchronization therapy (CRT). Myocardial scar adversely affects clinical outcomes after CRT.

OBJECTIVE

The purpose of this study in patients with an ideally deployed quadripolar left ventricular (LV) lead (QUAD) was to determine whether reducing QRS_area leads to an acute hemodynamic response (AHR) and whether scar affects this interaction.

METHODS

Patients (n = 26; age 69.2 ± 9.12 years [mean ± SD]) underwent assessment of the maximum rate of change of LV pressure (ΔLV dP/dt_max) during CRT using various left ventricular pacing locations (LVPLs). Cardiac magnetic resonance (CMR) scan was used to localize LV myocardial scar.

RESULTS

Interindividually, ΔQRS_area (area under the receiver operating characteristic curve [AUC] 0.81; P <.001) and change in QRS duration (ΔQRSd) (AUC 0.76; P <.001) predicted ΔLV dP/dt_max after CRT. Scar burden correlated with ΔQRS_area (r = 0.35; P = .003), ΔQRS_area (r = 0.35; P = .003), and ΔQRSd (r = 0.46; P <.001). A reduction in QRS_area was observed with LVPLs remote from scar (-3.28 ± 38.1 μVs) or in LVPLs in patients with no scar at all (-43.8 ± 36.8 μVs), whereas LVPLs over scar increased QRS_area (22.2 ± 58.4 μVs) (P <.001 for all comparisons). LVPLs within 1 scarred LV segment were associated with lower ΔLV dP/dt_max (-2.21% ± 11.5%) than LVPLs remote from scar (5.23% ± 10.3%; P <.001) or LVPLs in patients with no scar at all (10.2% ± 7.75%) (both P <.001).

CONCLUSION

Reducing QRS_area improves the AHR to CRT. Myocardial scar adversely affects ΔQRS_area and the AHR. These findings may support the use of ΔQRS_area and CMR in optimizing CRT using QUAD.

Laparoscopic versus open colorectal surgery in the acute setting (LaCeS trial): a multicentre randomized feasibility trial

BACKGROUND

Approximately 30 000 people undergo major emergency abdominal gastrointestinal surgery annually, and 36 per cent of these procedures (around 10 800) are carried out for emergency colorectal pathology. Some 14 per cent of all patients requiring emergency surgery have a laparoscopic procedure. The aims of the LaCeS (laparoscopic versus open colorectal surgery in the acute setting) feasibility trial were to assess the feasibility, safety and acceptability of performing a large-scale definitive phase III RCT, with a comparison of emergency laparoscopic versus open surgery for acute colorectal pathology.

METHODS

LaCeS was designed as a prospective, multicentre, single-blind, parallel-group, pragmatic feasibility RCT with an integrated qualitative study. Randomization was undertaken centrally, with patients randomized on a 1 : 1 basis between laparoscopic or open surgery.

RESULTS

A total of 64 patients were recruited across five centres. The overall mean steady-state recruitment rate was 1·2 patients per month per site. Baseline compliance for clinical and health-related quality-of-life data was 99·8 and 93·8 per cent respectively. The conversion rate from laparoscopic to open surgery was 39 (95 per cent c.i. 23 to 58) per cent. The 30-day postoperative complication rate was 27 (13 to 46) per cent in the laparoscopic arm and 42 (25 to 61) per cent in the open arm.

CONCLUSION

Laparoscopic emergency colorectal surgery may have an acceptable safety profile. Registration number: ISRCTN15681041 ( http://www.controlled-trials.com).

305Pacemaker therapy after cardiac valve replacement surgery: impact on heart failure hospitalizations

Background

Left ventricular (LV) function is a major determinant of long-term outcomes after valve replacement surgery. Although conventional (right ventricular) pacemaker therapy is life-saving, it may cause heart failure (HF).

Aims

To determine whether permanent pacemaker implantation (PPI) confers a risk of HF in surgical valve recipients.

Methods

The primary endpoint of HF hospitalization and the secondary endpoints of total mortality and total mortality / HF hospitalizations were compared in valve recipients with and without PPI. Traditional as well as multi-state, multivariable modelling was used to assess the influence of PPI on clinical outcomes.

Results

Amongst patients (n = 135,242) undergoing a first aortic (AVR; n = 111,674), mitral (MVR; n = 18,402) valve replacement, or AVR + MVR (n = 5,166) over 14 years in 176 centre, 12,952 (10.6%) had a PPI at any time during follow-up and 5,805 (4.3%) underwent PPI postoperatively. After 3.9 yrs (median, interquartile range: 6.1), heart failure (HF) hospitalizations (HR: 1.47, 95% C.I. 1.36-1.59), total mortality (HR: 1.10, 95% C.I. 1.05-1.16) and total mortality or HF hospitalizations (HR: 1.17, 95% C.I. 1.12-1.22; see figure) were higher in patients with post-operative PPI than in patients without. Multi-state modelling revealed that the transition hazard from PPI at any time to HF hospitalizations was markedly higher (transition hazard rate: 0.29, 95% C.I. 0.24-0.36) than from valve replacement surgery to HF hospitalization.

Conclusions

After valve replacement surgery, PPI is associated with increased HF hospitalization and total mortality, particularly after dual valve replacements.

Abstract Figure.

P1428The outcome of atrial fibrillation ablation in patients undergoing radiofrequency ablation, guided by novel indices incorporating force, time and power

Background

Ablation index (AI) and Lesion Size Index (LSI) are novel parameters that incorporates contact force, time, and power in a weighted formula. Recent studies have shown that such indices predict lesion size and durability of pulmonary vein isolation (PVI). However, the outcomes of ablation guided by indices of force-time-power, such as PV reconnections and atrial fibrillation recurrence, have not been well characterised.

Objectives

To determine the association between indices of force-time-power and acute PV reconnections, procedure and fluoroscopy time and AF recurrence in patients undergoing radiofrequency PVI.

Methods

PUBMED and EMBASE were searched using the terms "catheter ablation" AND "Ablation index" OR "Contact force" OR "Force time integral" OR "lesion size" from inception through 22 May 2019. Studies reporting the procedure time, ablation time, fluoroscopy time, and incidence of AI acute and late reconnection and AF recurrence were included.

Result

 Six studies were included in this study with 530 patients, which n = 416 were paroxysmal AF and 114 non-paroxysmal AF. All procedural characteristics (procedure, radiofrequency, and fluoroscopy times) were similar between AI guided and non-AI guided ablation (p &gt; 0.05). Two studies comparing mean PV reconnections in AI guided vs. AI Blinded. Two studies compared minimum AI in reconnected vs. non-reconnected PV segments. Acute PV segment reconnection was associated with a lower minimum AI vs. non-reconnection. In 3 studies reporting AI guided vs. AI blinded ablations, AI was associated with an increased freedom from AF after average follow-up of 12 months.

Conclusions

Radiofrequency ablation guided by AI/LSI was associated with lower acute PV reconnection rates and improved AF freedom after PVI. There was no difference in fluoroscopy, ablation or procedure time with the use of these novel parameters.

Abstract Figure.

Prognosis of incidental left bundle branch block

AIMS

Incidental left bundle branch block (iLBBB) is a frequent cause for cardiology referrals. In such instances, there is uncertainty as to its prognosis. We sought to determine the utility of cardiovascular magnetic resonance (CMR) in the risk stratification of patients with iLBBB.

METHODS AND RESULTS

Clinical events were collected in patients with iLBBB who had CMR. Controls had no cardiac symptoms or cardiac disease, a normal CMR scan and electrocardiogram. Amongst patients with iLBBB [n = 193, aged 62.7 ± 12.6 years (mean ± SD)], 110/193 (56.9%) had an abnormal phenotype (iLBBBCMR+) and 83/110 (43.0%) had a normal phenotype (iLBBBCMR-). Over 3.75 years (median; inter-quartile range: 2.7-5.5), iLBBBCMR+ had a higher total mortality [adjusted hazard ratio (aHR) 6.49, 95% confidence interval (CI) 1.91-22.0] and total mortality or major adverse cardiac events (MACEs; aHR 9.15, 95% CI 2.56-32.6) than controls (n = 107). In contrast, iLBBBCMR- had a similar risk of total mortality compared with controls, but total mortality or MACEs was higher (aHR 4.24, 95% CI 1.17-15.4; P = 0.028). Amongst iLBBB patients, both myocardial fibrosis (aHR 5.15, 95% CI 1.53-17.4) and left ventricular ejection fraction (LVEF)  ≤ 50% (aHR 3.88, 95% CI 1.67-9.06) predicted total mortality. Myocardial fibrosis plus LVEF ≤50% was associated with the highest risk of total mortality (aHR: 9.87, 95% CI 2.99-32.6) and total mortality or MACEs (aHR 3.98, 95% CI 1.73-9.11).

CONCLUSIONS

Outcomes in iLBBBCMR+ were poor whereas survival in iLBBBCMR- was comparable with controls. Myocardial fibrosis and LVEF <50% had an additive effect on the risk of clinical outcomes. A CMR scan is pivotal in risk-stratifying patients with iLBBB.

A randomised controlled trial of SMS messaging and calendar reminders to improve vaccination timeliness in infants

BACKGROUND

The effectiveness of SMS reminders in improving vaccination coverage has been assessed previously, with effectiveness varying between settings. However, there are very few studies on their effect on the timeliness of vaccination.

DESIGN

Unblinded, randomised controlled trial with blocked sampling.

METHODS

1594 Australian infants and young children were recruited to assess the impact of (1) SMS reminders only, (2) a personalised calendar, (3) SMS reminder and personalised calendar and (4) no intervention, on receipt of vaccine within 30 days of the due date. Outcomes were measured for receipt of vaccines due at 2, 4, 6, 12 and 18 months of age. A post-hoc assessment was also conducted of the impact of a new national "No jab No Pay" policy introduced during the trial, which removed philosophical objections as an exemption for financial penalties for non-vaccination.

RESULTS

There was a statistically significant improvement in on-time vaccination only at the 12 month schedule point amongst infants who received SMS reminders alone (RR 1.09, 95% CI 1.01-1.18) or in combination with a personalised calendar (1.11, CI 1.03-1.20) compared to controls. This impact was limited to participants who had received one or more previous doses late. No statistically significant impacts of calendar interventions alone were seen. There was a high rate of on-time compliance amongst control participants - 95%, 86%, 80%, 74% at the 4, 6, 12 and 18 month schedule points respectively, which increased more than 10 percentage points after implementation of the "No Jab, No Pay" policy.

CONCLUSIONS

SMS reminders are more effective in improving timeliness where pre-existing compliance is lower, but the 18 month schedule point appeared to be less amenable to intervention. Australia and New Zealand Clinical Trial Registration No. ACTRN12614000970640.

Biventricular pacemaker therapy improves exercise capacity in patients with non-obstructive hypertrophic cardiomyopathy via augmented diastolic filling on exercise

AIMS

Treatment options for patients with non-obstructive hypertrophic cardiomyopathy (HCM) are limited. We sought to determine whether biventricular (BiV) pacing improves exercise capacity in HCM patients, and whether this is via augmented diastolic filling.

METHODS AND RESULTS

Thirty-one patients with symptomatic non-obstructive HCM were enrolled. Following device implantation, patients underwent detailed assessment of exercise diastolic filling using radionuclide ventriculography in BiV and sham pacing modes. Patients then entered an 8-month crossover study of BiV and sham pacing in random order, to assess the effect on exercise capacity [peak oxygen consumption (VO₂ )]. Patients were grouped on pre-specified analysis according to whether left ventricular end-diastolic volume increased (+LVEDV) or was unchanged/decreased (-LVEDV) with exercise at baseline. Twenty-nine patients (20 male, mean age 55 years) completed the study. There were 14 +LVEDV patients and 15 -LVEDV patients. Baseline peak VO₂ was lower in -LVEDV patients vs. +LVEDV patients (16.2 ± 0.9 vs. 19.9 ± 1.1 mL/kg/min, P = 0.04). BiV pacing significantly increased exercise ΔLVEDV (P = 0.004) and Δstroke volume (P = 0.008) in -LVEDV patients, but not in +LVEDV patients. Left ventricular ejection fraction and end-systolic elastance did not increase with BiV pacing in either group. This translated into significantly greater improvements in exercise capacity (peak VO₂  + 1.4 mL/kg/min, P = 0.03) and quality of life scores (P = 0.02) in -LVEDV patients during the crossover study. There was no effect on left ventricular mechanical dyssynchrony in either group.

CONCLUSION

Symptomatic patients with non-obstructive HCM may benefit from BiV pacing via augmentation of diastolic filling on exercise rather than contractile improvement. This may be due to relief of diastolic ventricular interaction.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov NCT00504647.

Changes in QRS Area and QRS Duration After Cardiac Resynchronization Therapy Predict Cardiac Mortality, Heart Failure Hospitalizations, and Ventricular Arrhythmias

Background

Predicting clinical outcomes after cardiac resynchronization therapy (CRT) and its optimization remain a challenge. We sought to determine whether pre‐ and postimplantation QRS area (QRS_area) predict clinical outcomes after CRT.

Methods and Results

In this retrospective study, QRS_area, derived from pre‐ and postimplantation vectorcardiography, were assessed in relation to the primary end point of cardiac mortality after CRT with or without defibrillation. Other end points included total mortality, total mortality or heart failure (HF) hospitalization, total mortality or major adverse cardiac events, and the arrhythmic end point of sudden cardiac death or ventricular arrhythmias with or without a shock. In patients (n=380, age 72.0±12.4 years, 68.7% male) undergoing CRT over 7.7 years (median follow‐up: 3.8 years [interquartile range 2.3–5.3]), preimplantation QRS_area ≥102 μVs predicted cardiac mortality (HR: 0.36; P<0.001), independent of QRS duration (QRSd) and morphology (P<0.001). A QRS_area reduction ≥45 μVs after CRT predicted cardiac mortality (HR: 0.19), total mortality (HR: 0.50), total mortality or heart failure hospitalization (HR: 0.44), total mortality or major adverse cardiac events (HR: 0.43) (all P<0.001) and the arrhythmic end point (HR: 0.26; P<0.001). A concomitant reduction in QRS_area and QRSd was associated with the lowest risk of cardiac mortality and the arrhythmic end point (both HR: 0.12, P<0.001).

Conclusions

Pre‐implantation QRS_area, derived from vectorcardiography, was superior to QRSd and QRS morphology in predicting cardiac mortality after CRT. A postimplant reduction in both QRS_area and QRSd was associated with the best outcomes, including the arrhythmic end point.

P3646A systematic review and meta-analysis on spontaneous coronary artery dissection: epidemiology, risk factors and outcomes

Background

Spontaneous Coronary Artery Dissection (SCAD) is an elusive but increasingly recognised cause of Acute Coronary Syndrome (ACS). Most knowledge about SCAD has arisen from small to medium sized cohort studies that have been published since 2012.

Purpose

This systematic review and meta-analysis aimed to provide an update on SCAD's association with cardiovascular risk factors, angiographic variants and outcomes.

Methods

The term “Spontaneous Coronary Artery Dissection” was searched in PubMed, EMBASE and SCOPUS on the 2nd of February 2019, yielding a total of 1517 articles. Following exclusion (e.g. of isolated case reports and duplicate cohorts), 31 original studies that reported at least one desired parameter in patients with SCAD were included. Statistical analysis was performed independently for each parameter using random effects models.

Results

Of the k=31 studies (n=77,025 patients), only 3 were published before 2012 (n=68). Mean age was 62.4 years and 85.1% [78.9%-89.8%, I2=91.7, k=28] were female. Prevalence of associated conditions and traditional cardiovascular risk factors are outlined in the table. Importantly, only 37.4% [30.0%-45.4%, I2=77.0, k=10] were associated with a traditional Type 1 angiographic appearance. Yearly incidence was 3.4% [2.4%-4.4%, I2=73.4, k=16] for SCAD recurrence and 5.8% [4.1%-7.5%, I2=85.7, k=16] for MACE. Incidence of MACE at follow-up was 4.1% [1.7%-9.9%, I2=74.0, k=3] for conservative treatment and 7.2% [5.1%-10.3%, I2=43.7, k=4] for PCI (p=0.14).

Estimated prevalence of traditional cardiovascular risk factors, associated conditions and angiographic variants in cohorts of patients with SCAD Associated Patient Factor Number of Studies Prevalence (%, [95% CI]) Heterogeneity (I2) Hypertension 29 36.0 [29.9–42.6] 97.9% Dyslipidemia 27 28.7 [17.4–43.5] 99.7% Smoking 29 23.3 [14.5–35.3] 99.6% Depression/Anxiety 6 28.1 [19.3–38.9] 94.3% Fibromuscular Dysplasia 9 50.7 [40.0–61.3] 91.9% Type 1 Angiographic Appearance 11 37.4 [30.0–45.4] 77.0% Type 2 Angiographic Appearance 11 62.4 [50.0–73.3] 93.3% Type 3 Angiographic Appearance 6 10.2 [6.2–16.4] 78.3%

Incidence of Recurrence in SCAD Cohorts

Conclusions

This meta-analysis confirms associations of SCAD with fibromuscular dysplasia, anxiety and depression, and reveals a small but important risk of recurrence and MACE. Furthermore, a majority of SCAD cases present with non-traditional angiographic appearances highlighting the need for increased familiarity with this condition among treating physicians.

P989Incidence of appropriate implantable cardioverter defibrillator therapy and sudden cardiac death in cardiac sarcoidosis - a systematic review and meta-analysis

Background

Implantation of implantable cardioverter defibrillator (ICD) is a Class IIb indication in patients with Cardiac Sarcoid and with LVEF 36%-49% despite immunosuppression and optimal heart failure therapy.

Purpose

This systematic review and meta-analysis aimed to provide an estimate on the incidence of ventricular arrhythmias and risk of sudden cardiac death (SCD) in patients with CS.

Methods

The terms “Cardiac Sarcoidosis*” AND “Implantable Cardioverter Defibrillator” AND “Sudden Cardiac Death” were searched on PubMed, EMBASE, and Scopus on 21st of September 2018 yielding 759 articles. After exclusions, 12 studies met inclusion criteria.

Results

The 12 studies consisted of 612 patients with CS of which 534 had ICD implanted for primary or secondary prevention. Assuming appropriate device therapy as a surrogate for SCD, the annual incidence of appropriate ICD therapies and SCD combined was 6.3% (95% CI; 3.5%-9.1%) in primary prevention cohorts, 11.6% (95% CI; 7.8%-15.3%) in secondary prevention cohorts, and 8.7% (95% CI; 6.0%-11.5%) in both cohorts. The mean left ventricular ejection fraction (LVEF) was pooled as 59±7 (n=155) in primary prevention cohorts and 48±15 (n=48) in secondary prevention cohorts. However, the LVEF was 35±13 (n=28) in those with appropriate ICD therapy, and 49±16 (n=47) in those with ICDs without therapy.

Incidence of SCD in Combined Cohorts

Conclusion

The incidence of ventricular arrhythmias and SCD is high not only secondary but also in primary prevention cohorts of CS. This data supports the role of implanting ICDs for primary prevention in patients with CS with mild to moderate reduction in LVEF.

Acknowledgement/Funding

None

The effects of the neonicotinoid imidacloprid on gene expression and DNA methylation in the buff-tailed bumblebee Bombus terrestris

Neonicotinoids are effective insecticides used on many important arable and horticultural crops. They are nicotinic acetylcholine receptor agonists which disrupt the function of insect neurons and cause paralysis and death. In addition to direct mortality, there are numerous sublethal effects of low doses of neonicotinoids on bees. We hypothesize that some of these large array of effects could be a consequence of epigenetic changes in bees induced by neonicotinoids. We compared whole methylome (BS-seq) and RNA-seq libraries of the brains of buff-tailed bumblebee Bombus terrestris workers exposed to field-realistic doses of the neonicotinoid imidacloprid to libraries from control workers. We found numerous genes which show differential expression between neonicotinoid-treated bees and control bees, but no differentially methylated cytosines in any context. We found CpG methylation to be focused mainly in exons and associated with highly expressed genes. We discuss the implications of our results for future legislation.

Long-term clinical outcomes of cardiac resynchronization therapy with or without defibrillation: impact of the aetiology of cardiomyopathy

Aims

There is a continuing debate as to whether cardiac resynchronization therapy-defibrillation (CRT-D) is superior to CRT-pacing (CRT-P), particularly in patients with non-ischaemic cardiomyopathy (NICM). We sought to quantify the clinical outcomes after primary prevention of CRT-D and CRT-P and identify whether these differed according to the aetiology of cardiomyopathy.

Methods and results

Analyses were undertaken in the total study population of patients treated with CRT-D (n = 551) or CRT-P (n = 999) and in propensity-matched samples. Device choice was governed by the clinical guidelines in the United Kingdom. In univariable analyses of the total study population, for a maximum follow-up of 16 years (median 4.7 years, interquartile range 2.4–7.1), CRT-D was associated with a lower total mortality [hazard ratio (HR) 0.72] and the composite endpoints of total mortality or heart failure (HF) hospitalization (HR 0.72) and total mortality or hospitalization for major adverse cardiac events (MACE; HR 0.71) (all P < 0.001). After propensity matching (n = 796), CRT-D was associated with a lower total mortality (HR 0.72) and the composite endpoints (all P < 0.01). When further stratified according to aetiology, CRT-D was associated with a lower total mortality (HR 0.62), total mortality or HF hospitalization (HR 0.63), and total mortality or hospitalization for MACE (HR 0.59) (all P < 0.001) in patients with ischaemic cardiomyopathy (ICM). There were no differences in outcomes between CRT-D and CRT-P in patients with NICM.

Conclusion

In this study of real-world clinical practice, CRT-D was superior to CRT-P with respect to total mortality and composite endpoints, independent of known confounders. The benefit of CRT-D was evident in ICM but not in NICM.

Long-term outcomes of cardiac resynchronization therapy in adult congenital heart disease

BACKGROUND AND AIMS

Randomized, controlled trials of cardiac resynchronization therapy (CRT) excluded patients with adult congenital heart disease (ACHD). We sought to explore long-term clinical outcomes.

METHODS AND RESULTS

In this single-center, observational study, events were collected from hospital records on patients with structural ACHD (sACHD) and adults with ischemic (ICM) or nonischemic (NICM) cardiomyopathy undergoing CRT. Patients with sACHD (n = 23, age: 41.6 ± 13.5 years [mean ± standard deviation]) and adults with ICM (n = 533) or NICM (n = 458) were followed-up for 4.1 years (median; interquartile range: 2.2-6.1). Total mortality was 5/23 (21.7%; 4.4 per 100 person-years) in sACHD, 221/533 (41.5%; 11.8 per 100 person-years) in ICM, and 154/458 (33.6%; 9.7 per 100 person-years) in NICM. In univariate analyses, total mortality in sACHD was lower than in ICM (hazard ratio [HR]: 0.38; 95% confidence interval [CI] 0.15-0.91), but similar to NICM (HR: 0.48, 95% CI 0.20-1.16). Cardiac mortality in sACHD was similar to ICM (HR: 0.78, 95% CI 0.32-1.92) and NICM (HR: 1.12, 95% CI 0.45-2.78). Heart failure (HF) hospitalization rates were similar to ICM (HR: 0.44, 95% CI 0.11-1.77) and NICM (HR: 0.75, 95% CI 0.18-3.08). In multivariate analyses, no differences emerged in total mortality, cardiac mortality, or HF hospitalization between sACHD and NICM or ICM, after adjustment for age, sex, New York Heart Association class, diabetes, atrial rhythm, QRS duration, QRS morphology, systemic ventricular ejection fraction, and medical therapy.

CONCLUSION

Total mortality, cardiac mortality, and HF hospitalization after CRT in patients with sACHD was similar to adults with ICM or NICM.

Renal function and the long-term clinical outcomes of cardiac resynchronization therapy with or without defibrillation

Background and Aims

Patients with moderate‐to‐severe chronic kidney disease (CKD) are underrepresented in clinical trials of cardiac resynchronization therapy (CRT)‐defibrillation (CRT‐D) or CRT‐pacing (CRT‐P). We sought to determine whether outcomes after CRT‐D are better than after CRT‐P over a wide spectrum of CKD.

Methods and Results

Clinical events were quantified in relation to preimplant estimated glomerular filtration rate (eGFR) after CRT‐D (n = 410 [39.2%]) or CRT‐P (n = 636 [60.8%]) implantation. Over a follow‐up period of 3.7 years (median, interquartile range: 2.1–5.7), the eGFR < 60 group (n = 598) had a higher risk of total mortality (adjusted hazard ratio [aHR]: 1.28; P = 0.017), total mortality or heart failure (HF) hospitalization (aHR: 1.32; P = 0.004), total mortality or hospitalization for major adverse cardiac events (MACEs, aHR: 1.34; P = 0.002), and cardiac mortality (aHR: 1.33; P = 0.036), compared to the eGFR ≥ 60 group (n = 448), after covariate adjustment. In analyses of CRT‐D versus CRT‐P, CRT‐D was associated with a lower risk of total mortality (eGFR ≥ 60 HR: 0.65; P = 0.028; eGFR < 60 HR: 0.64, P = 0.002), total mortality or HF hospitalization (eGFR ≥ 60 aHR: 0.66; P = 0.021; eGFR < 60 aHR: 0.69, P = 0.007), total mortality or hospitalization for MACEs (eGFR ≥ 60 aHR: 0.70; P = 0.039; eGFR < 60 aHR: 0.69, P = 0.005), and cardiac mortality (eGFR ≥ 60 aHR: 0.60; P = 0.026; eGFR < 60 aHR: 0.55; P = 0.003).

Conclusion

In CRT recipients, moderate CKD is associated with a higher mortality and morbidity compared to normal renal function or mild CKD. Despite less favorable absolute outcomes, patients with moderate CKD had better outcomes after CRT‐D than after CRT‐P.