Heart Failure Low Output
Conditions
Keywords
Left Bundle Branch Optimized CRT,, Left Bundle Branch Area Pacing, left ventricular ejection fraction, quality of life, Heart failure
Brief summary
The purpose of this pilot clinical trial is to evaluate whether a novel cardiac resynchronization strategy, called LOT-CRT, is more effective than standard physiological pacing alone (LBBAP) in patients with heart failure. This is a randomized, single-center, crossover pilot study involving 10 patients. All participants will receive a specialized pacemaker (CRT-P) with leads implanted in two specific areas: the Left Bundle Branch Area (LBBAP) and the Coronary Sinus (CS). Because of the crossover design, each patient will serve as their own control, receiving two different pacing configurations in a random order: Active Phase (LOT-CRT): Simultaneous pacing of the left bundle branch and the coronary sinus. Control Phase (LBBAP alone): Pacing only the left bundle branch area. Each treatment phase will last 6 months, for a total follow-up of 12 months per patient. By testing both strategies in the same patient, this study will help clinicians identify the most effective way to restore heart synchrony and improve clinical outcomes in patients with advanced heart failure and conduction delays.
Detailed description
This is a single-center, randomized, crossover pilot clinical trial. Each patient will serve as their own control. Following the successful implantation of a device capable of stimulating the LBBAP and the coronary sinus, participants will be randomly assigned to one of two treatment sequences: Sequence A: LOT-CRT (LBBAP + CS) for 6 months, followed by LBBAP alone Sequence B: LBBAP alone for 6 months, followed by LOT-CRT Each treatment phase will last 6 months, followed by an end-point evaluation and a crossover. Since the hemodynamic effect of electrical stimulation is immediate, no washout period is required between phases. This study was designed as an exploratory pilot study; therefore, no formal sample size calculation was performed. The number of patients enrolled is considered adequate to assess the feasibility of the procedure, the safety of the crossover design, and to identify preliminary signals of clinical and electrical efficacy.
Interventions
DEVICELeft Bundle Branch Optimized CRT
The CS lead will be implanted in a posterolateral or lateral vein using venography and standard IV delivery sheaths. Proper lead placement is confirmed by stable fixation, pacing capture, and absence of diaphragmatic pacing. The configuration for each phase of the study (LOT-CRT or LBBAP alone) will be assigned during randomization.
DEVICEStimulation of the left bundle branch area (LBBAP)
The LBBAP lead will be implanted via a transvenous approach using the C315His sheath, targeting the left bundle branch area in the right ventricular septum, ideally between the basal septum and the mid-septal region. Criteria for confirming successful LBBAP capture will include: * Evidence of narrowing of the stimulated QRS complex compared to baseline. * Right bundle branch block morphology on the ECG-stimulus-to-R-wave time in V6 \<80 ms (if available). * Low and stable pacing threshold (\<1.5 V @ 0.4 ms). * Unipolar impedance between 400-1500 ohms. The CS lead will be implanted in a posterolateral or lateral vein using venography and standard IV delivery sheaths. Proper lead placement is confirmed by stable fixation, pacing capture, and absence of diaphragmatic pacing.
Sponsors
Clinica Cardio VID
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
TREATMENT
Masking
DOUBLE (Subject, Investigator)
Masking description
Since all patients will have both a coronary sinus electrode and a branch electrode (LBBAP) implanted, the study will be blinded only to the participants and to the investigators responsible for conducting the 6-minute walk test, the echocardiogram, and the NT-proBNP assessment. It will not be blinded to the electrophysiologists due to technical requirements. Additionally, outcome assessors and data analysts will also be blinded to the pacing mode (LBBAP or LOT - CRT). It will be blinded to the investigators and the patients. Outcome assessors and data analysts will also be blinded to the pacing mode (LBBAP or LOT - CRT).
Intervention model description
A single-center, randomized, crossover pilot clinical trial. Each patient will serve as their own control. Following the successful implantation of a device capable of stimulating the LBBAP and the coronary sinus, participants will be randomly assigned to one of two treatment sequences: Sequence A: LOT-CRT (LBBAP + CS) for 6 months, followed by LBBAP alone or Sequence B: LBBAP alone for 6 months, followed by LOT-CRT. Each treatment phase will last 6 months, followed by an end-point evaluation and a crossover. Since the hemodynamic effect of electrical stimulation is immediate, no washout period is required between phases. Randomization will be performed using permuted blocks to ensure an equitable distribution of eligible participants across the two types of interventions. This randomization will be conducted using a 1:1 ratio, and blocks of size 2 will be selected.
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
1. Age ≥18 years 2. Standard CRT-P indications according to ESC 2021 (EF ≤50%, QRS ≥130 ms, sinus rhythm or controlled AF) 3. NYHA class II-IV 4. Coronary venous anatomy suitable for placement of a coronary sinus electrode. 5. Signed informed consent. 6. Successful implantation of electrodes in the coronary sinus and in the left bundle branch area (LBBAP)
Exclusion criteria
1. Concomitant indication for implantation of an implantable cardioverter-defibrillator (ICD) or CRT-D 2. Significant uncorrected valvular disease or scheduled or anticipated cardiac surgery during the study period. 3. Anatomical or technical contraindication for lead implantation in the coronary sinus or for lead implantation in the coronary sinus (such as sinus stenosis, coronary sinus branches unsuitable for cannulation, inability to advance and/or stabilize the lead, among others) 4. Persistent atrial fibrillation with uncontrolled rate 5. Comorbidities that may limit life expectancy to \<1 year 6. Participation in another clinical trial that could confound the evaluation of results within the last 6 months. 7. Pregnancy or inadequate contraception 8. In the researcher's opinion, the participant would not comply with the activities and visits outlined in the study protocol
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Compare the effects of the LOT-CRT strategy versus left bundle branch block pacing (LBBAP) alone in each patient, comparing baseline to the end of the study FEVI, quality of life and functional class by NYHA. | 12 months | Investigators will evaluate the following parameters in each patient: Left ventricular ejection fraction (LVEF) by echocardiography and electrocardiogram; functional capacity (NYHA class) using the 6-minute walk test and symptoms reported by the patient; quality of life (MLHFQ) using the MLHFQ quality of life scale |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Change in end-systolic diameter | 12 months | Absolute (mm) and relative (%) change in LVESV between baseline and 6 months. |
| QRS Duration | 12 months | Absolute (ms) and relative (%) changes in the 12-lead ECG. |
| Change in end-diastolic diameter | 12 months | Absolute (mm) and relative (%) change in LVEDV between baseline and 6 months. |
| NT-proBNP | 12 months | Absolute (ng/mL) and relative (%) change in NT-proBNP from baseline to 6 months |
| Echocardiographic responder | 12 months | LVEF ≥10% elevation or LVESV ≥15% decreased |
| Echocardiographic super-responder | 12 months | LVEF ≥50% or LVESV ≥30% decrease |
| Composite Clinical Outcome | 12 months | Cardiovascular Death or Hospitalization for Heart Failure |
| Procedural parameters | 12 months | Thresholds, P- and R-waves, impedance of each electrode. |
| Procedure Time/Fluoroscopy | 12 months | Total procedure time in minutes/ total fluoroscopy time in minutes. |
Countries
Colombia
Contacts
PRINCIPAL_INVESTIGATORJuan F Agudelo, Electrophysiologist
Clinica CardioVID
STUDY_DIRECTORSusana Rios, Medical Epidemiologist
Clinica CardioVID
Outcome results
None listed