Heart Failure Low OutputLOTTO-CRTNCT07664189

LBBP + CSP Versus LBBP Alone for Cardiac Resynchronization Therapy

A study testing Left Bundle Branch Optimized CRT and Stimulation of the left bundle branch area (LBBAP) in people with Heart Failure Low Output, run by Clinica Cardio VID at 1 site in Colombia.

Enrolling by invitation

Enrolling by invitation. The study team selects and invites participants, usually from an existing group of patients.

Sites and contacts

Official record

Search all trials

Trial 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. Read more about this study

Who is it for?: Ages 18 years and older
Conditions the study is for: Heart Failure Low Output
What is being tested?: Left Bundle Branch Optimized CRT and Stimulation of the left bundle branch area (LBBAP)
Type of treatment: Injection or infusion, Medical device
Could I receive a placebo?: No, everyone receives an active treatment
How many people: 10 participants
Where: 1 siteColombia
Study dates: 9 Jun 2026to 1 Dec 2027
Phase: Interventional
Are there results?: Not yet: the study is under way

Key requirements

Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.

Ages 18 years and older
All sexes
No healthy volunteers
Adult, Older adult

Who may be able to join

Age ≥18 years
Standard CRT-P indications according to ESC 2021 (EF ≤50%, QRS ≥130 ms, sinus rhythm or controlled AF)
NYHA class II-IV
Coronary venous anatomy suitable for placement of a coronary sinus electrode.
Signed informed consent.
Successful implantation of electrodes in the coronary sinus and in the left bundle branch area (LBBAP)

Who cannot join

Concomitant indication for implantation of an implantable cardioverter-defibrillator (ICD) or CRT-D
Significant uncorrected valvular disease or scheduled or anticipated cardiac surgery during the study period.
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)
Persistent atrial fibrillation with uncontrolled rate
Comorbidities that may limit life expectancy to <1 year
Participation in another clinical trial that could confound the evaluation of results within the last 6 months.
Pregnancy or inadequate contraception
In the researcher's opinion, the participant would not comply with the activities and visits outlined in the study protocol

Trial locations and contacts

1 site in 1 country. Contact the study team or a site near you to ask about taking part.

Colombia1 site

Clinica CardioVID
Medellín, Antioquia, 050036

Other trials in Colombia

About this study

Official title: Left Bundle Branch Pacing + Coronary Sinus Pacing Versus Left Bundle Branch Pacing Alone for Cardiac Resynchronization Therapy in Patients Eligible for CRT-P A Randomized Crossover Pilot Clinical Trial

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.

Read the 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.

Conditions: Heart Failure Low Output
Being tested: Left Bundle Branch Optimized CRT, Stimulation of the left bundle branch area (LBBAP)
Keywords: Left Bundle Branch Optimized CRT,, Left Bundle Branch Area Pacing, left ventricular ejection fraction, quality of life, Heart failure
Medical subject headings: Heart Failure

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

Left Bundle Branch Optimized CRTDevice
Also called LOT-CRT, Left bundle branch block pacing + coronary sinus pacing, LBBAP + CS, LOT-CRT Strategy
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.
Stimulation of the left bundle branch area (LBBAP)Device
Also called Stimulation of the left branch only
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.

Study groups in NCT07664189
Study group	Role	What they receive
Sequence A	Active comparator	LOT-CRT (LBBAP + CS) for 6 months, followed by LBBAP alone Receives: Device: Left Bundle Branch Optimized CRT; Device: Stimulation of the left bundle branch area (LBBAP)
Sequence B	Active comparator	LBBAP for 6 months only, followed by LOT-CRT Receives: Device: Left Bundle Branch Optimized CRT; Device: Stimulation of the left bundle branch area (LBBAP)

What is being measured

The primary outcome is the main question the study is designed to answer.

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.
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
Measured: 12 months

Secondary outcomes (9)

Change in end-systolic diameter
Absolute (mm) and relative (%) change in LVESV between baseline and 6 months.
Measured: 12 months
QRS Duration
Absolute (ms) and relative (%) changes in the 12-lead ECG.
Measured: 12 months
Change in end-diastolic diameter
Absolute (mm) and relative (%) change in LVEDV between baseline and 6 months.
Measured: 12 months
NT-proBNP
Absolute (ng/mL) and relative (%) change in NT-proBNP from baseline to 6 months
Measured: 12 months
Echocardiographic responder
LVEF ≥10% elevation or LVESV ≥15% decreased
Measured: 12 months
Echocardiographic super-responder
LVEF ≥50% or LVESV ≥30% decrease
Measured: 12 months
Composite Clinical Outcome
Cardiovascular Death or Hospitalization for Heart Failure
Measured: 12 months
Procedural parameters
Thresholds, P- and R-waves, impedance of each electrode.
Measured: 12 months
Procedure Time/Fluoroscopy
Total procedure time in minutes/ total fluoroscopy time in minutes.
Measured: 12 months

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

9 Jun 20261 Dec 2027

First posted24 Jun 2026
Study start9 Jun 2026
Primary completion1 Jul 2027 (estimated)
Study completion1 Dec 2027 (estimated)

Resources

Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
Publications (13)Papers the sponsor has linked to this study.
Other trials for Heart Failure Low OutputStudies of the same condition, open and under way.
What the trial phases meanHow a treatment moves from first tests in people to approval.

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.

Study design

Study type: Interventional
Phase: Phase N/A
Primary purpose: Treatment
Allocation: Randomised
Intervention model: Crossover
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.
Masking: Double blind
Who is masked: Participant, Investigator
Enrolment: 10 participants (estimated)

IDs, dates and publications

ClinicalTrials.gov ID: NCT07664189
Sponsor's protocol ID: Clinica CardioVID
Other IDs: ERP -2025-14209
Acronym: LOTTO-CRT
Status last verified: Jul 2026
First submitted: 26 May 2026
Last updated: 23 Jul 2026
Results posted: No
Data monitoring committee: Yes
FDA-regulated drug: No
FDA-regulated device: Yes
Individual data sharing: Yes: Individual participant data, appropriately anonymized, that support the reported results will be made available to qualified researchers for the purposes of scientific research or meta-analysis. Requests must be addressed to the Principal Investigator and include a formal proposal. All requests will be subject to approval by the institutional ethics committee. As this is a study with a small sample size (10 patients), the protocol strictly enforces confidentiality; therefore, prior approval is always required to share these data. The data will be available from 6 months to 5 years following the publication of the main results.

Publications

Upadhyay GA, Jastrzebski M, Foley P, Chandrasekaran B, Whinnett Z, Schaller RD, Gardas R, Richardson T, Moskal P, Kudlik D, Stadler RW, Zimmerman P, Burrell J, Waxman R, Cornelussen RN, Lyne J, Herweg B, Vijayaraman P. Echocardiographic response from left bundle branch area pacing optimized cardiac resynchronization therapy (LOT-CRT) vs traditional CRT. Heart Rhythm. 2025 Oct;22(10):2616-2624. doi: 10.1016/j.hrthm.2025.04.026. Epub 2025 Apr 18.
PubMed 40254116
Chen X, Li X, Bai Y, Wang J, Qin S, Bai J, Wang W, Liang Y, Chen H, Su Y, Ge J. Electrical Resynchronization and Clinical Outcomes During Long-Term Follow-Up in Intraventricular Conduction Delay Patients Applied Left Bundle Branch Pacing-Optimized Cardiac Resynchronization Therapy. Circ Arrhythm Electrophysiol. 2023 Sep;16(9):e011761. doi: 10.1161/CIRCEP.122.011761. Epub 2023 Aug 14.
PubMed 37577815
Parale C, Bootla D, Jain A, Satheesh S, Anantharaj A, Ahmed AS, Sukumaran SK, Balaguru S, Selvaraj R. Comparison of electrocardiographic parameters between left bundle optimized cardiac resynchronization therapy (LOT-CRT) and left bundle branch pacing-cardiac resynchronization therapy (LBBP-CRT). Pacing Clin Electrophysiol. 2023 Aug;46(8):840-847. doi: 10.1111/pace.14793. Epub 2023 Jul 21.
PubMed 37477545
Jastrzebski M, Foley P, Chandrasekaran B, Whinnett Z, Vijayaraman P, Upadhyay GA, Schaller RD, Gardas R, Richardson T, Kudlik D, Stadler RW, Zimmerman P, Burrell J, Waxman R, Cornelussen RN, Lyne J, Herweg B. Multicenter Hemodynamic Assessment of the LOT-CRT Strategy: When Does Combining Left Bundle Branch Pacing and Coronary Venous Pacing Enhance Resynchronization?: Primary Results of the CSPOT Study. Circ Arrhythm Electrophysiol. 2024 Nov;17(11):e013059. doi: 10.1161/CIRCEP.124.013059. Epub 2024 Oct 23.
PubMed 39440428
Vijayaraman P. Left Bundle Branch Pacing Optimized Cardiac Resynchronization Therapy: A Novel Approach. JACC Clin Electrophysiol. 2021 Aug;7(8):1076-1078. doi: 10.1016/j.jacep.2021.04.005. Epub 2021 Jul 28. No abstract available.
PubMed 34332867
Burri H, Jastrzebski M, Cano O, Curila K, de Pooter J, Huang W, Israel C, Joza J, Romero J, Vernooy K, Vijayaraman P, Whinnett Z, Zanon F. EHRA clinical consensus statement on conduction system pacing implantation: endorsed by the Asia Pacific Heart Rhythm Society (APHRS), Canadian Heart Rhythm Society (CHRS), and Latin American Heart Rhythm Society (LAHRS). Europace. 2023 Apr 15;25(4):1208-1236. doi: 10.1093/europace/euad043.
PubMed 37061848
Glikson M, Burri H, Abdin A, Cano O, Curila K, De Pooter J, Diaz JC, Drossart I, Huang W, Israel CW, Jastrzebski M, Joza J, Karvonen J, Keene D, Leclercq C, Mullens W, Pujol-Lopez M, Rao A, Vernooy K, Vijayaraman P, Zanon F, Michowitz Y, Nielsen JC, Boersma L, Blomstrom-Lundqvist C, Kronborg MB, Chung MK, Tse HF, Khan HR, Leyva F, Rojel-Martinez U, Rucinski M, Varma N. European Society of Cardiology (ESC) clinical consensus statement on indications for conduction system pacing, with special contribution of the European Heart Rhythm Association of the ESC and endorsed by the Asia Pacific Heart Rhythm Society, the Canadian Heart Rhythm Society, the Heart Rhythm Society, and the Latin American Heart Rhythm Society. Europace. 2025 Mar 28;27(4):euaf050. doi: 10.1093/europace/euaf050.
PubMed 40159278
Jastrzebski M, Moskal P, Huybrechts W, Curila K, Sreekumar P, Rademakers LM, Ponnusamy SS, Herweg B, Sharma PS, Bednarek A, Rajzer M, Vijayaraman P. Left bundle branch-optimized cardiac resynchronization therapy (LOT-CRT): Results from an international LBBAP collaborative study group. Heart Rhythm. 2022 Jan;19(1):13-21. doi: 10.1016/j.hrthm.2021.07.057. Epub 2021 Jul 30.
PubMed 34339851
Su L, Wang S, Wu S, Xu L, Huang Z, Chen X, Zheng R, Jiang L, Ellenbogen KA, Whinnett ZI, Huang W. Long-Term Safety and Feasibility of Left Bundle Branch Pacing in a Large Single-Center Study. Circ Arrhythm Electrophysiol. 2021 Feb;14(2):e009261. doi: 10.1161/CIRCEP.120.009261. Epub 2021 Jan 9.
PubMed 33426907
Chung MK, Patton KK, Lau CP, Dal Forno ARJ, Al-Khatib SM, Arora V, Birgersdotter-Green UM, Cha YM, Chung EH, Cronin EM, Curtis AB, Cygankiewicz I, Dandamudi G, Dubin AM, Ensch DP, Glotzer TV, Gold MR, Goldberger ZD, Gopinathannair R, Gorodeski EZ, Gutierrez A, Guzman JC, Huang W, Imrey PB, Indik JH, Karim S, Karpawich PP, Khaykin Y, Kiehl EL, Kron J, Kutyifa V, Link MS, Marine JE, Mullens W, Park SJ, Parkash R, Patete MF, Pathak RK, Perona CA, Rickard J, Schoenfeld MH, Seow SC, Shen WK, Shoda M, Singh JP, Slotwiner DJ, Sridhar ARM, Srivatsa UN, Stecker EC, Tanawuttiwat T, Tang WHW, Tapias CA, Tracy CM, Upadhyay GA, Varma N, Vernooy K, Vijayaraman P, Worsnick SA, Zareba W, Zeitler EP. 2023 HRS/APHRS/LAHRS guideline on cardiac physiologic pacing for the avoidance and mitigation of heart failure. Heart Rhythm. 2023 Sep;20(9):e17-e91. doi: 10.1016/j.hrthm.2023.03.1538. Epub 2023 May 20.
PubMed 37283271
Sieniewicz BJ, Gould J, Porter B, Sidhu BS, Teall T, Webb J, Carr-White G, Rinaldi CA. Understanding non-response to cardiac resynchronisation therapy: common problems and potential solutions. Heart Fail Rev. 2019 Jan;24(1):41-54. doi: 10.1007/s10741-018-9734-8.
PubMed 30143910
Herweg B, Welter-Frost A, Vijayaraman P. The evolution of cardiac resynchronization therapy and an introduction to conduction system pacing: a conceptual review. Europace. 2021 Apr 6;23(4):496-510. doi: 10.1093/europace/euaa264.
PubMed 33247913
Glikson M, Nielsen JC, Kronborg MB, Michowitz Y, Auricchio A, Barbash IM, Barrabes JA, Boriani G, Braunschweig F, Brignole M, Burri H, Coats AJS, Deharo JC, Delgado V, Diller GP, Israel CW, Keren A, Knops RE, Kotecha D, Leclercq C, Merkely B, Starck C, Thylen I, Tolosana JM; ESC Scientific Document Group. 2021 ESC Guidelines on cardiac pacing and cardiac resynchronization therapy. Eur Heart J. 2021 Sep 14;42(35):3427-3520. doi: 10.1093/eurheartj/ehab364. No abstract available.
PubMed 34455430

Interested in taking part?

The sponsor has not listed a contact. The official record may have more details.

Talk to your doctor first and take this page with you. Only the study team can confirm whether you can join.

Questions to ask the study team

What is the study trying to find out?
What would I need to do, and how often would I visit?
Could I receive a placebo instead of the treatment?
What are the possible risks and benefits for me?
Will it cost me anything? Are travel or time paid for?
Can I keep seeing my own doctor during the study?
What happens when the study ends?

See sites and contacts

Recruiting
Restrictive Fluid Management In Liver Transplantation (REFIL)
Liver Transplantation (LT), End-stage Liver Disease (ESLD)
Active, not recruiting
Restrictive Fluid Management In Liver Transplantation (REFIL) - Pilot
Liver Transplantation, End-stage Liver Disease (ESLD)
RecruitingPhase 4
Landiolol in Mitral Valve Surgery
Cardiac Failure, Low Cardiac Output Syndrome
Enrolling by invitationObservational study
COR-INSIGHT: Optimizing Cardiovascular and Cardiopulmonary Outcomes with AI-Driven Multiplexed Indications Using COR ECG Wearable
Cardiopulmonary Failure, Myocardial Infarction (MI)

All Heart Failure Low Output trials

Study at a glance

From the registry record, last updated by the sponsor on 23 Jul 2026. Recruitment status is as the sponsor reported it: confirm with the study team.

Official title: Left Bundle Branch Pacing + Coronary Sinus Pacing Versus Left Bundle Branch Pacing Alone for Cardiac Resynchronization Therapy in Patients Eligible for CRT-P A Randomized Crossover Pilot Clinical Trial
ClinicalTrials.gov ID: NCT07664189
Acronym / sponsor ID: LOTTO-CRT / Clinica CardioVID
Conditions: Heart Failure Low Output
Keywords: Left Bundle Branch Optimized CRT,, Left Bundle Branch Area Pacing, left ventricular ejection fraction, quality of life, Heart failure
Study type: Interventional
Recruitment status: Enrolling by invitation
Enrolment: 10 participants (estimated)
Lead sponsor: Clinica Cardio VIDUniversity, hospital or other
Study start: 9 Jun 2026 (actual)
Primary completion: 1 Jul 2027 (estimated)
Study completion: 1 Dec 2027 (estimated)
First posted: 24 Jun 2026 (actual)
Results: Not posted in the source record

Clinical summary

The research question as the sponsor registered it. This describes what the study plans to test, not what it found.

Detailed description

Study design

Primary purpose: Treatment
Allocation: Randomised
Intervention model: Crossover
Masking: Double blind (participant, investigator)
Number of arms: 2
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.

Arm	Type	Receives
Sequence A	Active comparator	Device: Left Bundle Branch Optimized CRT, Device: Stimulation of the left bundle branch area (LBBAP)LOT-CRT (LBBAP + CS) for 6 months, followed by LBBAP alone
Sequence B	Active comparator	Device: Left Bundle Branch Optimized CRT, Device: Stimulation of the left bundle branch area (LBBAP)LBBAP for 6 months only, followed by LOT-CRT

Who may qualify

Ages: 18 years and older
Sex: All
Healthy volunteers: Not accepted
Age groups: Adult, Older adult

Key inclusion criteria (6 listed)

Age ≥18 years
Standard CRT-P indications according to ESC 2021 (EF ≤50%, QRS ≥130 ms, sinus rhythm or controlled AF)
NYHA class II-IV
Coronary venous anatomy suitable for placement of a coronary sinus electrode.
Signed informed consent.

Key exclusion criteria (8 listed)

Concomitant indication for implantation of an implantable cardioverter-defibrillator (ICD) or CRT-D
Significant uncorrected valvular disease or scheduled or anticipated cardiac surgery during the study period.
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)
Persistent atrial fibrillation with uncontrolled rate
Comorbidities that may limit life expectancy to <1 year

Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.

Interventions

Intervention	Type	Arms
Left Bundle Branch Optimized CRTAlso: LOT-CRT, Left bundle branch block pacing + coronary sinus pacing, LBBAP + CS, LOT-CRT StrategyThe 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.	Device	Sequence A, Sequence B
Stimulation of the left bundle branch area (LBBAP)Also: Stimulation of the left branch onlyThe 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.	Device	Sequence A, Sequence B

Primary outcome

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.
Time frame: 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

9 secondary outcomes

Change in end-systolic diameter
Time frame: 12 months
QRS Duration
Time frame: 12 months
Change in end-diastolic diameter
Time frame: 12 months
NT-proBNP
Time frame: 12 months
Echocardiographic responder
Time frame: 12 months
Echocardiographic super-responder
Time frame: 12 months
Composite Clinical Outcome
Time frame: 12 months
Procedural parameters
Time frame: 12 months
Procedure Time/Fluoroscopy
Time frame: 12 months

Results and safety

This study is still under way. Results are not available in the source record yet.

Research links

Official record on ClinicalTrials.govLast updated by the sponsor 23 Jul 2026.
Background: PubMed 40254116Upadhyay GA, Jastrzebski M, Foley P, Chandrasekaran B, Whinnett Z, Schaller RD, Gardas R, Richardson T, Moskal P, Kudlik D, Stadler RW, Zimmerman P, Burrell J, Waxman R, Cornelussen RN, Lyne J, Herweg B, Vijayaraman P. Echocardiographic response from left bundle branch area pacing optimized cardiac resynchronization therapy (LOT-CRT) vs traditional CRT. Heart Rhythm. 2025 Oct;22(10):2616-2624. doi: 10.1016/j.hrthm.2025.04.026. Epub 2025 Apr 18.
Background: PubMed 37577815Chen X, Li X, Bai Y, Wang J, Qin S, Bai J, Wang W, Liang Y, Chen H, Su Y, Ge J. Electrical Resynchronization and Clinical Outcomes During Long-Term Follow-Up in Intraventricular Conduction Delay Patients Applied Left Bundle Branch Pacing-Optimized Cardiac Resynchronization Therapy. Circ Arrhythm Electrophysiol. 2023 Sep;16(9):e011761. doi: 10.1161/CIRCEP.122.011761. Epub 2023 Aug 14.
Background: PubMed 37477545Parale C, Bootla D, Jain A, Satheesh S, Anantharaj A, Ahmed AS, Sukumaran SK, Balaguru S, Selvaraj R. Comparison of electrocardiographic parameters between left bundle optimized cardiac resynchronization therapy (LOT-CRT) and left bundle branch pacing-cardiac resynchronization therapy (LBBP-CRT). Pacing Clin Electrophysiol. 2023 Aug;46(8):840-847. doi: 10.1111/pace.14793. Epub 2023 Jul 21.
Background: PubMed 39440428Jastrzebski M, Foley P, Chandrasekaran B, Whinnett Z, Vijayaraman P, Upadhyay GA, Schaller RD, Gardas R, Richardson T, Kudlik D, Stadler RW, Zimmerman P, Burrell J, Waxman R, Cornelussen RN, Lyne J, Herweg B. Multicenter Hemodynamic Assessment of the LOT-CRT Strategy: When Does Combining Left Bundle Branch Pacing and Coronary Venous Pacing Enhance Resynchronization?: Primary Results of the CSPOT Study. Circ Arrhythm Electrophysiol. 2024 Nov;17(11):e013059. doi: 10.1161/CIRCEP.124.013059. Epub 2024 Oct 23.
Background: PubMed 34332867Vijayaraman P. Left Bundle Branch Pacing Optimized Cardiac Resynchronization Therapy: A Novel Approach. JACC Clin Electrophysiol. 2021 Aug;7(8):1076-1078. doi: 10.1016/j.jacep.2021.04.005. Epub 2021 Jul 28. No abstract available.
Background: PubMed 37061848Burri H, Jastrzebski M, Cano O, Curila K, de Pooter J, Huang W, Israel C, Joza J, Romero J, Vernooy K, Vijayaraman P, Whinnett Z, Zanon F. EHRA clinical consensus statement on conduction system pacing implantation: endorsed by the Asia Pacific Heart Rhythm Society (APHRS), Canadian Heart Rhythm Society (CHRS), and Latin American Heart Rhythm Society (LAHRS). Europace. 2023 Apr 15;25(4):1208-1236. doi: 10.1093/europace/euad043.
Background: PubMed 40159278Glikson M, Burri H, Abdin A, Cano O, Curila K, De Pooter J, Diaz JC, Drossart I, Huang W, Israel CW, Jastrzebski M, Joza J, Karvonen J, Keene D, Leclercq C, Mullens W, Pujol-Lopez M, Rao A, Vernooy K, Vijayaraman P, Zanon F, Michowitz Y, Nielsen JC, Boersma L, Blomstrom-Lundqvist C, Kronborg MB, Chung MK, Tse HF, Khan HR, Leyva F, Rojel-Martinez U, Rucinski M, Varma N. European Society of Cardiology (ESC) clinical consensus statement on indications for conduction system pacing, with special contribution of the European Heart Rhythm Association of the ESC and endorsed by the Asia Pacific Heart Rhythm Society, the Canadian Heart Rhythm Society, the Heart Rhythm Society, and the Latin American Heart Rhythm Society. Europace. 2025 Mar 28;27(4):euaf050. doi: 10.1093/europace/euaf050.
Background: PubMed 34339851Jastrzebski M, Moskal P, Huybrechts W, Curila K, Sreekumar P, Rademakers LM, Ponnusamy SS, Herweg B, Sharma PS, Bednarek A, Rajzer M, Vijayaraman P. Left bundle branch-optimized cardiac resynchronization therapy (LOT-CRT): Results from an international LBBAP collaborative study group. Heart Rhythm. 2022 Jan;19(1):13-21. doi: 10.1016/j.hrthm.2021.07.057. Epub 2021 Jul 30.
Background: PubMed 33426907Su L, Wang S, Wu S, Xu L, Huang Z, Chen X, Zheng R, Jiang L, Ellenbogen KA, Whinnett ZI, Huang W. Long-Term Safety and Feasibility of Left Bundle Branch Pacing in a Large Single-Center Study. Circ Arrhythm Electrophysiol. 2021 Feb;14(2):e009261. doi: 10.1161/CIRCEP.120.009261. Epub 2021 Jan 9.
Background: PubMed 37283271Chung MK, Patton KK, Lau CP, Dal Forno ARJ, Al-Khatib SM, Arora V, Birgersdotter-Green UM, Cha YM, Chung EH, Cronin EM, Curtis AB, Cygankiewicz I, Dandamudi G, Dubin AM, Ensch DP, Glotzer TV, Gold MR, Goldberger ZD, Gopinathannair R, Gorodeski EZ, Gutierrez A, Guzman JC, Huang W, Imrey PB, Indik JH, Karim S, Karpawich PP, Khaykin Y, Kiehl EL, Kron J, Kutyifa V, Link MS, Marine JE, Mullens W, Park SJ, Parkash R, Patete MF, Pathak RK, Perona CA, Rickard J, Schoenfeld MH, Seow SC, Shen WK, Shoda M, Singh JP, Slotwiner DJ, Sridhar ARM, Srivatsa UN, Stecker EC, Tanawuttiwat T, Tang WHW, Tapias CA, Tracy CM, Upadhyay GA, Varma N, Vernooy K, Vijayaraman P, Worsnick SA, Zareba W, Zeitler EP. 2023 HRS/APHRS/LAHRS guideline on cardiac physiologic pacing for the avoidance and mitigation of heart failure. Heart Rhythm. 2023 Sep;20(9):e17-e91. doi: 10.1016/j.hrthm.2023.03.1538. Epub 2023 May 20.
Background: PubMed 30143910Sieniewicz BJ, Gould J, Porter B, Sidhu BS, Teall T, Webb J, Carr-White G, Rinaldi CA. Understanding non-response to cardiac resynchronisation therapy: common problems and potential solutions. Heart Fail Rev. 2019 Jan;24(1):41-54. doi: 10.1007/s10741-018-9734-8.
Background: PubMed 33247913Herweg B, Welter-Frost A, Vijayaraman P. The evolution of cardiac resynchronization therapy and an introduction to conduction system pacing: a conceptual review. Europace. 2021 Apr 6;23(4):496-510. doi: 10.1093/europace/euaa264.
Individual participant dataSharing planned: Yes. Individual participant data, appropriately anonymized, that support the reported results will be made available to qualified researchers for the purposes of scientific research or meta-analysis. Requests must be addressed to the Principal Investigator and include a formal proposal. All requests will be subject to approval by the institutional ethics committee. As this is a study with a small sample size (10 patients), the protocol strictly enforces confidentiality; therefore, prior approval is always required to share these data. The data will be available from 6 months to 5 years following the publication of the main results.

Related trials for Heart Failure Low Output

Recruiting
Restrictive Fluid Management In Liver Transplantation (REFIL)
Liver Transplantation (LT), End-stage Liver Disease (ESLD)
Active, not recruiting
Restrictive Fluid Management In Liver Transplantation (REFIL) - Pilot
Liver Transplantation, End-stage Liver Disease (ESLD)
RecruitingPhase 4
Landiolol in Mitral Valve Surgery
Cardiac Failure, Low Cardiac Output Syndrome
Enrolling by invitationObservational study
COR-INSIGHT: Optimizing Cardiovascular and Cardiopulmonary Outcomes with AI-Driven Multiplexed Indications Using COR ECG Wearable
Cardiopulmonary Failure, Myocardial Infarction (MI)

Referral and contact

AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.

Juan F Agudelo, Electrophysiologist principal investigator

Clinica CardioVID

Susana Rios, Medical Epidemiologist study director

Clinica CardioVID

1 site in 1 country: see every site and its status.

Questions about this trial

What is this clinical trial studying?

A study testing Left Bundle Branch Optimized CRT and Stimulation of the left bundle branch area (LBBAP) in people with Heart Failure Low Output, run by Clinica Cardio VID at 1 site in Colombia.

The full registered description is in the About this study section and the official record.

Who may be eligible to take part?

The sponsor lists 6 inclusion and 8 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.

Is this clinical trial currently recruiting?

The record says: enrolling by invitation, as of the sponsor's last update on 23 Jul 2026. Status can change between updates, so confirm with the study contact before making plans.

Where is the study taking place?

The record lists 1 site in Colombia. Whether a site is taking part right now should be confirmed with that site. See every site.

What are the possible benefits and risks?

They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.

Are results available for this study?

This study is still under way. Results are not available in the source record yet.

How can a doctor refer a patient or contact the research team?

The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

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. (time frame: 12 months). It is what the study was designed to measure, not a finding.

Where can I read the original study information?

On the ClinicalTrials.gov record for NCT07664189, which also lists 13 linked publications.

Does a listing mean the treatment is approved or proven to work?

No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.

How often is this information updated?

AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 23 Jul 2026.