PINCHcm 1.0
Research type
Research Study
Full title
Paced dyssynchrony and myocardial perfusion IN apiCal Hcm (PINCHcm)
IRAS ID
252440
Contact name
Saidi Mohiddin
Contact email
Sponsor organisation
Joint Research Management Office (JRMO), Barts Health NHS Trust
Duration of Study in the UK
1 years, 0 months, 0 days
Research summary
Hypertrophic cardiomyopathy (HCM) is the most common inherited heart disease. A relatively common subgroup of HCM patients have apical HCM – a type of heart muscle disease that causes abnormal muscle thickening towards the tip (apex) of the heart. This can impair the heart’s own blood flow through the thickened heart muscle. We think this is one of the causes for symptoms such as shortness of breath and chest pain. If medications are ineffective at treating symptoms, there are few further options available, limited to invasive heart surgery.
We also believe that, by altering the settings of patients’ permanent pacemakers, it may be possible to reduce the abnormal ‘squeezing’ effect at the thickened tip of heart muscle and thereby improve blood flow through this heart muscle. We want to test whether this change in pacemaker setting has any impact on symptoms, exercise tolerance and the blood flow through the heart muscle. We will test the latter using ultrasound (echocardiography) and magnetic resonance imaging (MRI) of the heart.
This two-phase study involves participants being in the study for approximately 6 months. This is a single centre study, although potential participants may be identified at other hospitals by collaborating clinicians. Eligible participants will have apical HCM and an existing cardiac pacemaker device. Phase A of the study will assess changes in blood flow through the heart muscle during different pacemaker settings. Phase B of the study enters those same patients into a 6-month follow-up period. Here, the assessment of secondary outcomes will allow collection of baseline statistical data for the design of an outcomes-based clinical trial. Patients will ONLY be entered into phase B of the study if an improvement is seen in heart muscle blood flow with pacing during phase A.Lay summary of study results:
Eleven patients were recruited to the study. In nine of these patients, the primary outcome data were collected after successful interpretation of cardiac magnetic resonance imaging in two pacemaker settings. Pacing in the ventricles caused a change in myocardial blood flow (perfusion) in every patient. In the majority, pacing made the perfusion worse. In some, it made it better. There are some factors that may explain the direction of response. These are hypothesis generating and should be explored in future work.REC name
London - Bloomsbury Research Ethics Committee
REC reference
19/LO/1881
Date of REC Opinion
16 Dec 2019
REC opinion
Favourable Opinion