Overview
This will be a two-arm investigator-initiated randomized controlled study of patients with nHCM and LV ejection fraction ≥50% and NYHA II-III symptoms, normal intrinsic conduction system and pre-existing suitable dual-chamber implantable cardioverter defibrillators (ICD) systems. Patients will be randomly assigned to either personalized accelerated pacing (using the myPACE+ algorithm with mono-fractional exponent) or usual care groups. At baseline and after 3 months of pacing all patients will undergo a CPET, echocardiogram, blood work for NT-proBNP levels and complete the KCCQ-OSS and HCMSQ, questionnaires.
The investigator team hypothesizes that personalized accelerated pacing will be safe and improve symptoms and heart-failure related quality of life, physical activity, pVO2, biomarkers (i.e. NT-proBNP), diastolic parameters and cardiac structure.
Description
This will be a two-arm investigator-initiated randomized controlled study of patients with nHCM and LV ejection fraction≥50% and NYHA II-III symptoms, normal intrinsic conduction system and pre-existing suitable dual-chamber implantable cardioverter defibrillators (ICD) systems. Patients will be randomly assigned to either personalized accelerated pacing (using the myPACE+ algorithm with mono-fractional exponent) or usual care groups. At baseline and after 3 months of pacing all patients will undergo a CPET, echocardiogram, blood work for NT-proBNP levels and complete the KCCQ-OSS and HCMSQ, questionnaires.
The investigator team hypothesizes that personalized accelerated pacing will be safe and improve symptoms and heart-failure related quality of life, physical activity, pVO2, biomarkers (i.e. NT-proBNP), diastolic parameters and cardiac structure. An interim data safety analysis will be conducted.
Eligibility
Inclusion Criteria:
- Non obstructive HCM: Left Ventricular Outflow Tract (LVOT) gradient <30mmHg at rest and with provocation
- Left ventricular ejection fraction (LVEF) ≥50%
- New York Heart Association (NYHA II-III) symptoms
- Normal intrinsic conduction system
- Suitable dual-chamber implantable cardioverter defibrillators (ICD) system
Exclusion Criteria:
- Pregnancy
- LVEF <50%
- LVOT gradient > 30mmHg at rest or with provocation
- Prolonged PR > 250ms
- Baseline RV-pacing burden of > 1% more than moderate valvular stenosis or regurgitation
- Aortic valve replacement in the past one year
- Significant primary pulmonary disease on home oxygen
- Uncontrolled hypertension as defined by BP >160/100 mmHg on two measurements ≥15 minutes apart