Medical Arm of the Interagency Registry for Mechanically Assisted Circulatory Support

Study ID

Cancer Related

Healthy Volunteers

Study Sites

  • Clements University Hospital

Lynn Fernandez

Principal Investigator
Jennifer Thibodeau, M.D.

Official Title

Medical Arm of the Interagency Registry for Mechanically Assisted Circulatory Support

Brief Overview

Medamacs is a prospective, observational study of ambulatory patients with advanced heart
failure. The study enrolls patients who have not yet received a Left Ventricular Assist
Device (LVAD) but who receive their care at a hospital with a Joint Commission certified
mechanical circulatory support program.

Medamacs is funded through the Interagency for Mechanically Assisted Circulatory Support


Participants between 18 and 80 years old with low ejection fraction history and
hospitalization for heart failure within the past year will be screened for the study. All
subjects who have been admitted to the heart failure service will be screened and recruited,
either as an inpatient or during their first outpatient follow-up appointment by the
investigator and research staff caring for patients in the advanced heart failure program.

Eligibility for enrollment will be based only upon information that is clinically available
at the time of screening. The history of prior hospitalizations will be available from
clinical records.

Routine evaluation and triage of ambulatory patients with advanced heart disease includes
echocardiography and functional assessment with peak oxygen consumption and frequently 6
minute walk distance. The elements of information required for estimation of the Seattle
Heart Failure Risk score will be gleaned from laboratory data, or imputed as described in
the Seattle score literature. The research coordinator will enter this data onto a currently
available website for calculation of the Seattle score.

Eligibility will be determined by the inclusion and exclusion criteria and the study
research team will approach individual subjects who are potential candidates for
participation once the subject's primary physician has given permission to approach. Only
persons with a scientific or ethical reason will be excluded. Incarcerated prisoners have
been excluded by this protocol.

Participants will be followed every 6 months for 24 months after two baseline visits. The 6
month and 18 month follow ups consist of telephone interviews. Follow ups at 12 months and
24 months consists of routine clinical visits.

Approximately 350 patients from 12 centers in the United States will be enrolled over a 12
month period.

Participant Eligibility


Patients with Advanced Heart Failure

1. Age 18-80 years

2. New York Heart Association class III-IV heart failure for 45 of the last 60 days

3. Left ventricular ejection fraction ≤ 35%

4. Heart failure diagnosis or typical symptoms for 12 months

5. Use of evidence based oral medications (beta-blockers, ACE-inhibitors/ARBs,
aldosterone antagonist) for at least 3 months prior to enrollment or documented
medication contraindication or intolerance.

6. Hospitalization for heart failure within the previous 12 months (other than for
elective procedure)

7. Informed consent given

In Addition, they must have at least one of the following:

An additional unplanned hospitalization during the previous 12 months for a total of at
least 2 inpatient hospitalizations lasting >24 hours with heart failure as the primary or
secondary diagnosis within the previous 12 months


1. Peak oxygen uptake (VO2) <55% of age- and sex-predicted (using Wasserman equation) OR
a peak VO2 ≤16 ml/kg/min for men and ≤14 ml/kg/min for women in a test with an RER
>1.08 on cardiopulmonary exercise testing.

2. 6-minute walk distance <300 meters without non-cardiac limitation.

3. Serum BNP > 1000 (NT-proBNP > 4000 pg/ml) as outpatient or at hospital discharge.


Seattle Heart Failure Model Score > 1.5.


1. Age >80 years or <18 years

2. Non-cardiac diagnosis anticipated to limit 2-year survival (≥30-50% mortality within
2 years from non-cardiac diagnosis)

3. Primary functional limitation from non-cardiac diagnosis even if not likely to limit

4. QRS > 120msec and planned biventricular pacemaker implant or biventricular pacemaker
implantation within past 90 days

5. Current home intravenous inotrope therapy

6. Chronic hemodialysis or peritoneal dialysis

7. Scheduled for non-ventricular assist device cardiac surgery on current hospital

8. Obvious anatomical or other major contra-indication to any cardiac surgery in the
future (e.g. previous pneumonectomy, advanced connective tissue disease)

9. Actively listed for heart transplant as UNOS Status 1 or 2

10. History of cardiac amyloidosis

11. Dominant lesion of at least moderate aortic or mitral stenosis or congenital
structural heart defect.