This trial is active, not recruiting.

Condition heart failure, congestive
Treatments torsion optimized, usual care
Phase phase 3
Sponsor University of Calgary
Collaborator Heart and Stroke Foundation of Canada
Start date March 2009
End date December 2016
Trial size 60 participants
Trial identifier NCT00867984, 7345220000


Approximately 40% of resynchronization therapy recipients do not appear to clearly benefit. These patients are termed 'non-responders'. This study will assess whether a heart ultrasound (echo) technique called 'torsion imaging' can be used to increase the likelihood of benefit from resynchronization therapy.

United States No locations recruiting
Other countries No locations recruiting

Study Design

Allocation randomized
Endpoint classification efficacy study
Intervention model parallel assignment
Masking double blind (subject, outcomes assessor)
Primary purpose treatment
Torsion-guided VV optimization plus AV optimization.
torsion optimized
Torsion optimized VV timing plus AV optimization (VTI)
(Active Comparator)
AV optimization only.
usual care
AV optimization (VTI) only

Primary Outcomes

Improved functional class (≥ 1 class) & remodeling (either ≥ 10% relative reduction in LV ESV or a ≥ 5% absolute increase in LV EF).
time frame: Follow up (3-6 months) versus baseline.

Secondary Outcomes

dyssynchrony and torsion
time frame: Follow-up (3-6 months) vs. baseline
mitral regurgitation
time frame: Follow-up (3-6 months) vs. baseline
N-terminal BNP level
time frame: Follow-up (3-6 months) vs. baseline
quality of life
time frame: Follow-up (3-6 months) vs. baseline

Eligibility Criteria

Male or female participants at least 18 years old.

Inclusion Criteria: - non-response to CRT as indicated, - stable doses of ACE I / ARB and beta-blocker for ≥ 2 months, & - controlled heart rate if in atrial fibrillation. Exclusion Criteria: - inadequate images to assess torsion - no significant augmentation in torsion with optimization - unable or unwilling to provide informed consent, - medical condition other than HF likely to cause death within 6 months, - cardiac transplant planned, - myocardial infarction or revascularization since CRT implant.

Additional Information

Official title Torsion Optimization to Reduce Symptoms and Improve Outcomes in Non-responders (TORSION). A Randomized Comparison of Torsion-imaging Guided Optimization vs. Usual Settings.
Principal investigator Derek V Exner, MD, MPH
Description Background: Despite advances in pharmacotherapy, patients with heart failure (HF) are at high risk for death and hospitalization. Over 25% of patients with systolic HF have dyssynchronous ventricular contraction that impairs left ventricular (LV) function and results in HF progression. Cardiac resynchronization therapy (CRT) is designed to synchronize ventricular mechanical activity, improving cardiac output and reducing HF symptoms. As shown in our pilot data, at least 40% of patients do not respond to CRT despite pre-screening for the presence of longitudinal (long axis) mechanical (velocity) dyssynchrony and targeting LV lead placement to the latest site of latest velocity. Methods to improve the rates of response to CRT are required. Torsion imaging guided optimization of CRT timing is a promising approach and will be tested in this study. Primary hypothesis: Optimization of inter-ventricular (VV) timing, guided by torsion imaging, will increase functional capacity and reduce LV end systolic volume [ESV] in CRT in patients who have not responded after ≥ 6 months. CRT response will be defined by a ≥ 1 functional class improvement and either a ≥ 10% reduction in LV ESV or a ≥ 5% increase in EF at follow-up versus baseline. Secondary aims: To compare the following in torsion-guided vs usual care patients: a) echo parameters (intra-LV and VV dyssynchrony and torsion, and mitral regurgitation), b) N-terminal BNP levels, and c) generic / disease-specific quality of life. Methods: Randomized study of patients who have not responded to CRT after ≥ 6 months.
Trial information was received from ClinicalTrials.gov and was last updated in November 2015.
Information provided to ClinicalTrials.gov by University of Calgary.