Clinical Outcomes and Prognosis

1338157 - Myocardial scar and association with long term outcomes in patients with permanent pacemakers.

Friday, January 27, 2023

12:20 PM – 1:20 PM

Location: Pacific Jewel

Presenting Author(s)

Peter P. Swoboda, PhD

Consultant Cardiologist & Senior Lecturer
University of Leeds
Leeds, England, United Kingdom

Primary Author(s)

MS

Mubien Shabi

Cardiology Imaging Fellow
University of Leeds, United Kingdom

Co-Author(s)

CS

Christopher Saunderson, MD, MB

Consultant Cardiologist
University of Leeds, England, United Kingdom
LB

Louise A. Brown, PhD

Clinical Research Fellow
Leeds Institute of Cardiovascular and Metabolic Medicine
Leeds, England, United Kingdom
WJ

Wasim Javed, MBChB, MRes

Cardiology Clinical Research Fellow/ Registrar
Leeds Institute of Cardiovascular and Metabolic Medicine, United Kingdom
NS

Noor Sharrack, MBChB, MRCP, DTM&H

Clinical Research Fellow
University of Leeds, England, United Kingdom
Eylem Levelt, PhD

Associate Professor and Honorary Consultant
University of Leeds
Leeds, England, United Kingdom
John P. Greenwood, PhD

Professor
University of Leeds
Leeds, England, United Kingdom
Sven Plein, MD, PhD

Professor
University of Leeds
Leeds, England, United Kingdom

Disclosure(s):

Sven Plein, PhD, FSCMR: No financial relationships to disclose

Background: Long-term right ventricular (RV) pacing leads to heart failure or a decline in left ventricular (LV) function in up to a fifth of patients1 . We aimed to establish whether the presence of focal left ventricular myocardial fibrosis detected by late gadolinium enhancement on cardiovascular magnetic resonance (CMR) is associated with long term adverse outcomes in patients with long term cardiac devices.

Methods: Between February 2018 and March 2019, we prospectively recruited two cohorts1:
1) Patients with high grade atrioventricular block who were planned to have a cardiac device implanted and anticipated to have a high burden of RV pacing (N=60) and
2) Patients with a cardiac device implanted in the prior 3 years with an RV pacing burden < 5%. (N=42).

All patients underwent CMR for the assessment of myocardial scar.

Patients were followed up by review of electronic records and pacemaker checks until censoring for a composite endpoint of all-cause mortality, heart failure hospitalisation and new atrial fibrillation lasting >24 hours.

Results: Myocardial scar was present in 53 (52%) patients.

Over a median follow up of 2.9 years there were 46 MACE events in 38 patients (19 deaths, 13 heart failure hospitalisations, 14 atrial fibrillation episodes).

On Cox regression analysis, age (HR 1.04, P=0.03), myocardial scar (HR 2.67, P=0.008), and LVEF (HR 0.95, P=0.04) were all associated with outcomes.

RV pacing burden (%) was associated with outcomes in patients with myocardial scar (HR 1.01, P= 0.02) but not in those without scar (HR 1.00, P=0.91). In patients with scar, RV pacing burden >24% was associated with adverse outcomes.

Conclusion: In patients with cardiac pacemakers, myocardial scar was associated with adverse outcomes. RV pacing burden was only associated with outcomes in those with scar.

Given that fibrosis can be identified before device implantation, it has a potential role in identifying those at risk of LV dysfunction and future heart failure, offering a potential selection criterion for an optimised pacing strategy.

Further studies are needed to investigate whether identification of myocardial scar by CMR may have a role in risk stratification and device selection in patients undergoing pacemaker implantation.