The Effect of CRT on the Frank Starling Mechanism

Launched by GUY'S AND ST THOMAS' NHS FOUNDATION TRUST · Aug 8, 2023

Keywords

ClinConnect Summary

This clinical trial is exploring how a specific heart function principle, known as the Frank Starling Mechanism, is affected by a treatment called Cardiac Resynchronisation Therapy (CRT). The Frank Starling Mechanism basically means that the more blood the heart receives, the more it can pump out with each beat. However, in some patients with heart problems, this mechanism doesn't work as well, making it harder for their hearts to pump blood effectively. The researchers want to see if CRT, a type of pacemaker therapy, can improve this mechanism in patients with heart failure, as previous studies in animals have shown promise but have not yet been tested in humans.

To participate in this study, individuals need to be aged between 65 and 74, have a specific type of pacemaker, and meet certain heart health criteria (like having a weakened heart function if in the CRT group, or being in better heart health if in the control group). Participants will undergo an ultrasound scan of their heart while their pacemaker settings are adjusted, which will help researchers measure how well their heart is pumping before and after CRT treatment. This study aims to identify which patients might benefit most from CRT and improve their heart function. It’s important to note that individuals with certain conditions, like persistent irregular heartbeats or those who are pregnant, are not eligible to participate.

Gender

ALL

Eligibility criteria

• Inclusion Criteria:
• • • Ability to provide informed consent to participate and willing to comply with the clinical investigation plan and follow-up schedule.
• • Existing dual chamber pacemaker or ICD including atrial lead and RV lead.
• • RV pacing percentage \>40%.
• • CRT group - Severe left ventricular systolic impairment (LVEF≤35%). Clinical symptoms of heart failure despite optimum medical therapy (NYHA class II-IV).
• • Control group - LVEF \>50%.
• Exclusion Criteria:
• • • Previous treated with CRT (existing LV lead/His-Bundle lead/Left Bundle Branch Area lead).
• • Persistent atrial fibrillation
• • Female participants who are pregnant, lactating or planning pregnancy during the course of the study.
• • Participation in other studies with active treatment / investigational arm