Effect of outflow tract gradient reduction on arrhythmia in HOCM

• Research type

  Research Study

• Full title

  The effect of left ventricular outflow gradient reduction on arrhythmia burden in obstructive hypertrophic cardiomyopathy

• IRAS ID

  110329

• Contact name

  Saidi Mohiddin

• Contact email

  saidi.mohiddin@bartshealth.nhs.uk

• Sponsor organisation

  Barts Health NSH Trust

• Research summary

  Hypertrophic cardiomyopathy (HCM) is the commonest inherited heart disease and cause of sudden death (SD) in otherwise healthy young people. Arrangement of heart muscle fibres is very abnormal, leading to heart muscle thickening (hypertrophy) which may result in obstruction to blood flow out of the heart (LVOTO). Retrospective studies associate LVOTO with an increase in mortality, as well as heart rhythm disturbances (arrhythmia) including ventricular tachycardia (VT), which may be fatal, and atrial fibrillation (AF), which may result in stroke. Treatment of LVOTO with surgery has suggested a possible reduction in SD, and shocks in patients who have implantable cardiac defibrillators, although how it does this is not clear.
  The aim of this prospective study is to examine the effect of LVOTO reduction using an established nonsurgical technique, alcohol septal ablation (ASA), on arrhythmia in both the short term, i.e procedural-related and the longer term. In order to investigate this, we will continuously monitor heart rhythm using implantable recording devices (ICM), which will be implanted ≥ 1 month before ASA. Patients will be enrolled from Barts Health NHS trust and will be imaged with echocardiography and magnetic resonance imaging prior to ICM implantation in order to record tissue characteristics and haemodynamic (pressure) measurements before treatment. Patients will be followed up for 15 months and heart rhythm will be monitored. The ICM will then be explanted, following which imaging will be repeated. The main outcome is the proportion of patients with VT during the month before ASA compared to the 12th month after treatment. A number of secondary outcome data will also be collected including amount of AF. This will allow us to clarify the effect of LVOTO reduction on arrhythmic burden and SD risk, and correlate it with any changes in haemodynamics or tissue characteristics following ASA.

• REC name

  London - Queen Square Research Ethics Committee

• REC reference

  13/LO/0170

• Date of REC Opinion

  24 May 2013

• REC opinion

  Further Information Favourable Opinion