Cardiovascular and Neurohormonal Effects of Faster Atrial Pacing Rate - Full Text View

Purpose

Many patients with heart failure are unable to increase their heart rate appropriately when their body needs increased blood flow. As a result, they may be unable to mobilize excess fluid that their body retains. We hypothesize that we can provide assistance to their body in mobilizing this fluid by artificially increasing their heart rate using a pacemaker. We plan to conduct a prospective clinical trial to evaluate this hypothesis.

We will enroll participants from a pool of patients who already have biventricular pacemakers implanted. We will screen them using a blood test that is a rough estimate of volume overload and then confirm the results of this test with echocardiography, an ultrasound of their heart. Patients who meet the inclusion criteria will be randomly assigned to have their pacemakers adjusted or to have no intervention. They will be unaware of which group they are in.

Following adjustment, they will be monitored for six hours. Prior to the pacemaker adjustment, several tests will be performed to evaluate heart function and the levels of hormones related that are affected by heart failure. These tests will be repeated at the end of the six hour observation period in both groups. Following the second set of tests, patients who had their pacemakers adjusted will be reset to their original settings.

Condition	Intervention
Heart Failure	Device: Medtronic CRT (InSync or Concerto) Device: Medtronic CRT (Insync or Concerto)

Study Type:	Interventional
Study Design:	Allocation: Randomized Endpoint Classification: Safety/Efficacy Study Intervention Model: Parallel Assignment Masking: Single Blind (Subject) Primary Purpose: Treatment
Official Title:	Cardiovascular and Neurohormonal Effects of Faster Atrial Pacing Rate for Six Hours in Patients With Congestive Heart Failure, Heart Rate <70 Beats Per Minute and Fluid Overload.

Resource links provided by NLM:

MedlinePlus related topics: Heart Failure

U.S. FDA Resources

Further study details as provided by Columbia University:

Primary Outcome Measures:

Cardiac output [ Time Frame: 8 hours ] [ Designated as safety issue: No ]

Secondary Outcome Measures:

Changes in transthoracic impedence [ Time Frame: 8 hours ] [ Designated as safety issue: No ]
Changes in B-type Natriuretic Peptide (BNP) [ Time Frame: 8 hours ] [ Designated as safety issue: No ]
Changes in norepinephrine [ Time Frame: 8 hours ] [ Designated as safety issue: No ]
Changes in renin [ Time Frame: 8 hours ] [ Designated as safety issue: No ]

Enrollment:	3
Study Start Date:	April 2011
Study Completion Date:	September 2012
Primary Completion Date:	September 2012 (Final data collection date for primary outcome measure)

Arms	Assigned Interventions
Experimental: 1 Ambulatory out-patients will be identified at Columbia-Presbyterian and New York University Medical Centers.	Device: Medtronic CRT (InSync or Concerto) Patients will come to clinic in the morning for baseline measurements. Subsequently, the atrial pacing rate will be increased to 85bpm for 6 hours. Patients will eat a standard breakfast provided by the hospital prior to the treatment session, and then will fast for the six-hour observation period. Patients will remain in supine position and will be clinically monitored for 6 hours. All patients will be on continuous cardiac monitors. Vital signs and symptoms of congestion/ischemia will be recorded every hour. Other Name: Medtronic CRT pacemaker (InSync or Concerto)
Sham Comparator: 2 Ambulatory out-patients will be identified at Columbia-Presbyterian and New York University Medical Centers.	Device: Medtronic CRT (Insync or Concerto) Patients will come to clinic in the morning for baseline measurements.To maintain blinding, patients in the control group will be given the illusion that their pacer has been adjusted, but the settings will remain unchanged. Patients will eat a standard breakfast provided by the hospital prior to the treatment session, and then will fast for the six-hour observation period. Patients will remain in supine position and will be clinically monitored for 6 hours. All patients will be on continuous cardiac monitors. Vital signs and symptoms of congestion/ischemia will be recorded every hour. Other Name: Medtronic CRT pacemaker (Insync or Concerto)

Arms

Assigned Interventions

Experimental: 1

Ambulatory out-patients will be identified at Columbia-Presbyterian and New York University Medical Centers.

Device: Medtronic CRT (InSync or Concerto)

Patients will come to clinic in the morning for baseline measurements. Subsequently, the atrial pacing rate will be increased to 85bpm for 6 hours. Patients will eat a standard breakfast provided by the hospital prior to the treatment session, and then will fast for the six-hour observation period. Patients will remain in supine position and will be clinically monitored for 6 hours. All patients will be on continuous cardiac monitors. Vital signs and symptoms of congestion/ischemia will be recorded every hour.

Other Name: Medtronic CRT pacemaker (InSync or Concerto)

Sham Comparator: 2

Ambulatory out-patients will be identified at Columbia-Presbyterian and New York University Medical Centers.

Device: Medtronic CRT (Insync or Concerto)

Patients will come to clinic in the morning for baseline measurements.To maintain blinding, patients in the control group will be given the illusion that their pacer has been adjusted, but the settings will remain unchanged. Patients will eat a standard breakfast provided by the hospital prior to the treatment session, and then will fast for the six-hour observation period. Patients will remain in supine position and will be clinically monitored for 6 hours. All patients will be on continuous cardiac monitors. Vital signs and symptoms of congestion/ischemia will be recorded every hour.

Other Name: Medtronic CRT pacemaker (Insync or Concerto)

Detailed Description:

Many patients with heart failure suffer from chronotropic incompetence, an inability to raise their heart rate in response to metabolic demand. Previous studies have shown that brief increases in pacing rates in patients with biventricular pacemakers can improve cardiac contractility. We hypothesize that the benefits of an increased biventricular pacing rate could be sustained and would improve cardiovascular and neurohormonal parameters in patients suffering from volume overload. We intend to prospectively evaluate this hypothesis in a singleblind randomized trial. We will screen 40 patients who have previously implanted biventricular pacemakers and an elevated B-type Natriuretic Peptide (BNP) level and confirm that their wedge pressure is increased by echocardiography. Following enrollment, patients with elevated wedge pressure will be randomly assigned to have their atrial pacing rate increased to 85 beats per minute or to be unchanged. Patients will be unaware of their treatment assignment. They will be observed for six hours in a monitored setting. The primary outcome will be cardiac output, as measured noninvasively by the Innocor and by the NICOM (Cheetah Medical Inc., Israel) system before and after the observation period. Secondary outcomes will include changes in neurohormonal measures and transthoracic impedance as measured by the OptiVol (Medtronic Inc.) system. If this proof-of-concept study demonstrates a positive effect, future research would evaluate the ability of increased pacing rates to prevent or abort decompensation of Congestive Heart Failure (CHF).

Eligibility

Ages Eligible for Study:	18 Years to 90 Years
Genders Eligible for Study:	Both
Accepts Healthy Volunteers:	No

Criteria

Inclusion Criteria:

Age>18
Congestive Heart Failure (CHF) (>6 months duration)
Left Ventricular Ejection Fraction (LVEF) <40%
Functional Class III
Stable oral treatment (>1 month),
Implanted Medtronic CRT system (ideally 50% of them with the OptiVol system) with an atrial pacing lead
Low heart rate (sinus rhythm or atrial pacing <70 bpm)
Symptomatically stable (with no clinical requirement for adjustments in medical therapy, i.e. diuretics)
Increase in intrathoracic fluid as evidenced by:
B-type Natriuretic Peptide (BNP) >200; and
Transthoracic Doppler-echocardiography (TTE) wedge (E/E') >15.

Exclusion Criteria:

Atrial fibrillation
Stable or unstable angina
Myocardial infarction within 6 months before the study
Intravenous inotropic support
Noncardiac condition limiting exercise ability (i.e. severe rheumatoid arthritis or osteoarthritis, chronic pulmonary disease requiring daily beta-agonists)
Pregnant or breast feeding women. Women of child bearing potential must have a negative serum pregnancy test prior to enrollment.
Severe renal failure (creatinine> 2.5 mg/dl, hemodialysis or peritoneal dialysis)
Known hepatic impairment (total bilirubin >3 mg/dL, albumin <2.8 mg/dL, or increased ammonia levels if performed)
Hemoglobin (hgb) <8 mg %, or active bleeding requiring transfusion

Contacts and Locations

Please refer to this study by its ClinicalTrials.gov identifier: NCT00698139

Locations

United States, New York
Columbia University
New York, New York, United States, 10032

Sponsors and Collaborators

Columbia University

Medtronic

Investigators

Principal Investigator:

Paolo Colombo, MD

Columbia University

More Information

No publications provided

Responsible Party:	Paolo Colombo, Herbert Irving Assistant Professor of Medicine, Columbia University
ClinicalTrials.gov Identifier:	NCT00698139 History of Changes
Other Study ID Numbers:	AAAC6786
Study First Received:	June 11, 2008
Last Updated:	September 18, 2012
Health Authority:	United States: Institutional Review Board

Keywords provided by Columbia University:

heart failure
chronotropic incompetence
biventricular pacemaker

Additional relevant MeSH terms:

Heart Failure
Heart Diseases
Cardiovascular Diseases

ClinicalTrials.gov processed this record on May 23, 2013