IRONMAN: Effect of mechanIcal circulatoRy Support ON Exercise Capacity aMong pAtieNts With Heart Failure
Study Details
Study Description
Brief Summary
This study will evaluate how the cardiovascular system interacts with mechanical hearts to provide blood flow to the body during exercise. Two aims are proposed: 1) to determine the impact of a mechanical heart on exercise pressor reflexes in heart failure patients; and 2) to define the primary determinant(s) of exercise capacity in heart failure patients before and after device implantation.
| Condition or Disease | Intervention/Treatment | Phase |
|---|---|---|
|
|
Study Design
Arms and Interventions
| Arm | Intervention/Treatment |
|---|---|
| Advanced Heart Failure 40 patients with advanced heart failure scheduled to undergo Left Ventricular Assist Device (LVAD) insertion will be recruited for testing. Test subjects will complete testing prior to, and following LVAD implantation. |
|
| Healthy controls 10 age-matched healthy individuals will be recruited to establish normal/reference values. |
|
| Mild Heart Failure A second control group comprised of 10 age-matched individuals will be recruited to establish normal/reference values for individuals with mild, medically managed heart failure. |
Outcome Measures
Primary Outcome Measures
- Changes in the sympathetic neural response. [4 weeks prior to implantation and 6 months post implantation.]
The primary outcome will be the difference in the muscle sympathetic neural response (MSNA) to handgrip and post-exercise circulatory arrest (PECA) before and after Continuous-flow left ventricular assist device (CF-LVAD) insertion
- Change in VO2. [4 weeks prior to implantation and 6 months post implantation.]
The primary outcome will be the change in the VO2 (maximum rate of oxygen consumption) before and after CF-LVAD insertion.
Secondary Outcome Measures
- Changes in the hemodynamic response. [4 weeks prior to implantation and 6 months post implantation.]
This outcome will evaluate any difference in the hemodynamic response (heart rate and blood pressure) to handgrip and PECA before and after CF-LVAD
- VO2 relationship and ventilatory threshold (1) [4 weeks prior to implantation and 6 months post implantation.]
Cardiac output (Qc): VO2 relationship and ventilatory threshold before and after CF-LVAD insertion.
- VO2 relationship and ventilatory threshold (2). [4 weeks prior to implantation and 6 months post implantation.]
Determinants of Qc after CF-LVAD insertion (ie, contribution from device v. contribution from left ventricle).
- VO2 relationship and ventilatory threshold (3). [4 weeks prior to implantation and 6 months post implantation.]
Qc, VO2, ventilatory threshold and exercise capacity at increased pump speed.
- VO2 relationship and ventilatory threshold (4). [4 weeks prior to implantation and 6 months post implantation.]
Bloodflow to the periphery, as measured by transcranial Doppler to assess brain bloodflow during exercise/activity.
- Oxygen uptake and utilization [4 weeks prior to implantation and 6 months post implantation.]
Cerebral and musculoskeletal oxygen uptake by near-infrared spectroscopy
Eligibility Criteria
Criteria
Advanced Heart Failure-
Inclusion Criteria:
- Individuals with severely reduced left ventricular systolic function that are scheduled to undergo LVAD insertion
Exclusion Criteria:
-
uncontrolled diabetes with peripheral neuropathy (interferes with acquisition of MSNA signal)
-
Individuals with clinical right ventricular failure, defined as moderate-severely reduced RV systolic function on echocardiography, or clinical evidence of RV failure (elevated jugular venous pressures, significant peripheral edema)
-
Individuals with moderate-severe preexisting aortic insufficiency, as these patients will typically undergo a Park stitch at time of CF-LVAD insertion to permanently close the aortic valve and prevent worsening aortic insufficiency; and
-
Disorders that adversely influence exercise ability (e.g. arthritis, peripheral vascular disease, pulmonary disease)
Mild Heart Failure -
Inclusion Criteria:
-
Individuals with medically managed left ventricular systolic function that are NOT scheduled to undergo LVAD insertion
-
HF patients with ejection fraction <35-40%
Exclusion Criteria:
-
Individuals requiring systemic anticoagulation with vitamin-K antagonists or new/direct oral anticoagulants ("NOAC"/"DOAC")
-
Disorders that adversely influence exercise ability (e.g. arthritis, peripheral vascular disease, pulmonary disease)
-
History of uncontrolled arrhythmias (e.g. ventricular tachycardia or nonsustained ventricular tachycardia).
Healthy Controls -
Inclusion Criteria:
- Persons without a past medical history of cardiovascular disease or related disease (e.g. hypertension, diabetes, peripheral vascular disease, arrhythmias, stroke/transient ischemic attack) and are not taking any cardiac-related medications (e.g. antihypertensive medications)
Exclusion Criteria:
-
Individuals requiring systemic anticoagulation with vitamin-K antagonists or new/direct oral anticoagulants ("NOAC"/"DOAC")
-
Disorders that adversely influence exercise ability (e.g. arthritis, peripheral ascular disease).
Contacts and Locations
Locations
| Site | City | State | Country | Postal Code | |
|---|---|---|---|---|---|
| 1 | University of Colorado Snschutz Medical Campus | Aurora | Colorado | United States | 80045 |
Sponsors and Collaborators
- University of Colorado, Denver
Investigators
- Principal Investigator: William K Cornwell, MD, University of Colorado, Denver
Study Documents (Full-Text)
None provided.More Information
Publications
None provided.- 16-1635