Heart Failure, Left Bundle-Branch Block, Left Ventricular Systolic Dysfunction, Non-Specific Intraventricular Conduction Defect, Right Bundle-Branch Block
Conditions
Keywords
Cardiac resynchronization therapy, His bundle pacing, Haemodynamics, ECGI
Brief summary
The aim of this study is to compare the effectiveness of multiple modalities of cardiac resynchronisation therapy using high precision acute electrical and haemodynamic measurements.These modalities include biventricular pacing and conduction system pacing utilising His bundle and left bundle pacing. Conduction system pacing is a more physiological form of pacing. The study hypothesises that this will produce more effective cardiac resynchronisation.
Detailed description
This is a single centre acute electrical/haemodynamic and observational study of a subgroup of patients with heart failure. A total of 60 will be recruited. The acute study involves within patient comparison of biventricular and conduction system pacing using detailed electrical mapping and high precision haemodynamic measurement protocol. Participants will have permanent conduction system pacing if; * Baseline left bundle branch block and QRS \> 140ms or QRS \>150ms and any QRS morphology AND * Conduction system pacing is successful at reducing QRS duration by 20ms or more with satisfactory pacing parameters. Participants who receive permanent conduction system pacing will have follow up at 6 weeks, 3 months, 6 months and 12 months. Non-invasive markers including mechanical activation pattern (echocardiography and cardiac MRI) and electrical activation pattern (ultra-high frequency electrocardiography) will be used to identify the characteristics of patients who benefit from conduction system pacing.
Interventions
DEVICEHis-bundle pacing.
Cardiac resynchronisation therapy can be achieved using biventricular pacing involving placement of three leads into the right atrium, right ventricle and coronary sinus (epicardial left ventricle). Alternatively the third lead may be placed at the bundle of His or left ventricular septum to pace the left bundle directly.
Sponsors
Imperial College London
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
TREATMENT
Masking
NONE
Intervention model description
60 patients with heart failure, severe left ventricular systolic dysfunction and cardiac conduction abnormality (QRS \> 120ms) will be recruited and undergo an attempt at His bundle, left bundle pacing and biventricular pacing. Patients will have acute haemodynamic and electrical measurements.
Eligibility
Sex/Gender
ALL
Age
18 Years to 100 Years
Healthy volunteers
No
Inclusion criteria
* Patients referred for conventional CRT * Severe heart failure (LVEF, a measure of heart pumping, \< 35% - severe) * Prolonged QRS duration (\>120ms) * Adults willing to take part (age \> 18 years) * Able to give consent
Exclusion criteria
* Unable to give consent * Children (age \< 18 years) * Pregnant women
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Acute change is systolic blood pressure | 20 minutes | Mean change in systolic blood pressure (mmHg) from atrial pacing to AV sequential CRT pacing (HBP, LBP, epiBVP and combined HPB with epiLVP) at optimal AV delay measured in mmHg. |
| Acute electrical measurements | 20 minutes | Mean change in left ventricular activation time (Milliseconds) (measured using ECGI) during AV sequential CRT pacing (HBP, LBP, epiBVP and combined HPB with epiLVP) at optimal AV delay measured in Milliseconds. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Heart failure symptoms | 6 months | Heart failure symptoms of patients with permanent conduction system leads will be assessed at follow up at 3 month, 6 months and 12 months. The symptoms will be assessed using the Minnesota living with heart failure questionnaire score. |
| Conduction system battery longevity | 6 weeks, 3 months, 6 months, 12 months. | The measurements include battery longevity measured in months. |
| Cardiopulmonary exercise testing | 6 months | Patients with permanent conduction system leads will undergo symptom assessment with a repeat cardio-pulmonary exercise test to measure MVO2 in litres/minute. |
| Left ventricular ejection fraction | 12 months | Patients with permanent conduction system leads will undergo a repeat echocardiography and measure their left ventricular ejection fraction. |
| Conduction system lead threshold | 6 weeks, 3 months, 6 months, 12 months. | The measurements include lead threshold to achieved QRS narrowing measured in Volts at 0.5ms and 1ms. |
Countries
United Kingdom
Outcome results
None listed