Aortic-Radial Pressure Gradients Post CPB
| Status: | Recruiting |
|---|---|
| Conditions: | Peripheral Vascular Disease, Cardiology |
| Therapuetic Areas: | Cardiology / Vascular Diseases |
| Healthy: | No |
| Age Range: | 40 - 80 |
| Updated: | 3/10/2019 |
| Start Date: | June 12, 2017 |
| End Date: | June 30, 2019 |
| Contact: | Kenichi Ueda, MD, PhD |
| Email: | kenichi-ueda@uiowa.edu |
| Phone: | 319-356-2633 |
Correlation Between Arterial Stiffness and Aortic-to-radial Pressure Gradient After Cardiopulmonary Bypass
This study will examine whether pre-operative, non-invasive arterial stiffness measurements
can be used to predict which patients will develop an aortic-to-radial pressure gradient
after coronary artery bypass graft (CABG) surgery. A previous small study by Kanazawa, et al.
demonstrated in patients who developed an aortic-to-radial pressure gradient after CABG
surgery, the pulse wave velocity (PWV) was higher in the aorta and decreased when moving
toward the radial artery. In the patients who did not develop a pressure gradient, the PWV
started lower in the aorta and increased when moving towards the periphery.
The purpose of this investigation is to examine whether pre-operative PWV measurements can be
used to identify patients who will develop an aortic to radial pressure gradient after CABG
surgery.
Applanation tonometry will be performed on the right carotid and femoral arteries to assess
carotid-femoral pulse wave velocity, a surrogate for aortic stiffness. (SphygmoCor system,
AtCor Medical, Sydney, Australia). The measurement will be obtained before induction of
general anesthesia in the presurgical area. Also in the presurgical area, a non-invasive
cardiac output (CO) measurement will be obtained by using the ICON Device (Osypka Medical, La
Jolla, California). This CO value will be used to compare to the CO values obtained
invasively in the operating room.
can be used to predict which patients will develop an aortic-to-radial pressure gradient
after coronary artery bypass graft (CABG) surgery. A previous small study by Kanazawa, et al.
demonstrated in patients who developed an aortic-to-radial pressure gradient after CABG
surgery, the pulse wave velocity (PWV) was higher in the aorta and decreased when moving
toward the radial artery. In the patients who did not develop a pressure gradient, the PWV
started lower in the aorta and increased when moving towards the periphery.
The purpose of this investigation is to examine whether pre-operative PWV measurements can be
used to identify patients who will develop an aortic to radial pressure gradient after CABG
surgery.
Applanation tonometry will be performed on the right carotid and femoral arteries to assess
carotid-femoral pulse wave velocity, a surrogate for aortic stiffness. (SphygmoCor system,
AtCor Medical, Sydney, Australia). The measurement will be obtained before induction of
general anesthesia in the presurgical area. Also in the presurgical area, a non-invasive
cardiac output (CO) measurement will be obtained by using the ICON Device (Osypka Medical, La
Jolla, California). This CO value will be used to compare to the CO values obtained
invasively in the operating room.
The purpose of the study is determine if there is a relationship between pre-operative
vascular characteristics including, carotid-femoral pulse wave velocity (cfPWV), Augmentation
Index(AI) and central aortic pressure, and the development of a pressure gradient between the
aorta and radial artery after cardiopulmonary bypass.
The procedures necessary to achieve the desired outcomes are as follows. The first
measurement made by the research team will be pre-operative cardiac output (CO) measurement.
The ICON device is a non-invasive device that measures CO, or the amount of blood that your
heart pumps per minute. This device utilizes four stickers that are attached to skin, two on
the left side of the neck and two located on the left side of the chest. These stickers
function similarly to electrocardiogram (EKG) stickers that measure the electrical activity
of your heart. After attachment of the stickers, the ICON device will be used to make a
measurement of CO, which takes 1-2 minutes. After the measurement, the stickers will be
removed and the ICON device will not be used again in the study.
Secondly, pre-operative cfPWV, AI, and central aortic pressure measurements will be made. The
Sphygmocor device will be utilized to make the pre-operative cfPWV, AI and central aortic
pressure measurements. First, the AI measurements will be made using a non-invasive blood
pressure cuff placed on the right arm. The patient's blood pressure will be measured twice in
a row with this special blood pressure cuff. The blood pressure cuff on the right arm will be
removed and then a cuff will be placed around the right thigh. Measurements will be made with
a paper ruler from the patient's neck to the cuff on their leg. To make the cfPWV
measurements, the cuff on the thigh will inflate while a pressure probe will be placed on the
skin of the patient's right neck. Four measurements of cfPWV will be made with this
technique.
The intraoperative central aortic pressure measurement will be accomplished with the help of
the cardiothoracic surgeon. The surgeon will place a catheter in the aorta as part of the
coronary artery bypass grafting surgery. This catheter will be connected to the artificial
heart-lung machine. Prior to turning on the heart-lung machine, the pressure in the aorta
will be measured with this catheter. This is the standard of care for this type of surgery
and will not delay the surgery. After the artificial heart-lung machine is turned off but
before the catheter is removed from the aorta, the pressure will once again be measured.
In order to measure intraoperative CO values, we will utilize the pulmonary artery (PA)
catheter that was placed at the beginning of the surgery.. The patient will have a catheter
placed in the right side of the neck that will travel through the heart and into a branch of
the artery that goes from the heart to the lungs. This catheter will have the ability to
measure the amount of blood that is pumped from the heart per minute. At the same times that
the pressure in the aorta is measured (as above), the amount of blood that is pumped from the
heart per minute will be measured.
Lastly measurement of peripheral artery blood pressure will be accomplished with a right
radial arterial catheter. Prior to the start of surgery, the patient will receive a special
catheter in the radial artery of their right arm. This is the standard of care for blood
pressure monitoring in this type of surgery. At the same times during the surgery that the
pressure is being measured from the aortic catheter, the pressure will be measured from the
catheter in the right radial artery.
vascular characteristics including, carotid-femoral pulse wave velocity (cfPWV), Augmentation
Index(AI) and central aortic pressure, and the development of a pressure gradient between the
aorta and radial artery after cardiopulmonary bypass.
The procedures necessary to achieve the desired outcomes are as follows. The first
measurement made by the research team will be pre-operative cardiac output (CO) measurement.
The ICON device is a non-invasive device that measures CO, or the amount of blood that your
heart pumps per minute. This device utilizes four stickers that are attached to skin, two on
the left side of the neck and two located on the left side of the chest. These stickers
function similarly to electrocardiogram (EKG) stickers that measure the electrical activity
of your heart. After attachment of the stickers, the ICON device will be used to make a
measurement of CO, which takes 1-2 minutes. After the measurement, the stickers will be
removed and the ICON device will not be used again in the study.
Secondly, pre-operative cfPWV, AI, and central aortic pressure measurements will be made. The
Sphygmocor device will be utilized to make the pre-operative cfPWV, AI and central aortic
pressure measurements. First, the AI measurements will be made using a non-invasive blood
pressure cuff placed on the right arm. The patient's blood pressure will be measured twice in
a row with this special blood pressure cuff. The blood pressure cuff on the right arm will be
removed and then a cuff will be placed around the right thigh. Measurements will be made with
a paper ruler from the patient's neck to the cuff on their leg. To make the cfPWV
measurements, the cuff on the thigh will inflate while a pressure probe will be placed on the
skin of the patient's right neck. Four measurements of cfPWV will be made with this
technique.
The intraoperative central aortic pressure measurement will be accomplished with the help of
the cardiothoracic surgeon. The surgeon will place a catheter in the aorta as part of the
coronary artery bypass grafting surgery. This catheter will be connected to the artificial
heart-lung machine. Prior to turning on the heart-lung machine, the pressure in the aorta
will be measured with this catheter. This is the standard of care for this type of surgery
and will not delay the surgery. After the artificial heart-lung machine is turned off but
before the catheter is removed from the aorta, the pressure will once again be measured.
In order to measure intraoperative CO values, we will utilize the pulmonary artery (PA)
catheter that was placed at the beginning of the surgery.. The patient will have a catheter
placed in the right side of the neck that will travel through the heart and into a branch of
the artery that goes from the heart to the lungs. This catheter will have the ability to
measure the amount of blood that is pumped from the heart per minute. At the same times that
the pressure in the aorta is measured (as above), the amount of blood that is pumped from the
heart per minute will be measured.
Lastly measurement of peripheral artery blood pressure will be accomplished with a right
radial arterial catheter. Prior to the start of surgery, the patient will receive a special
catheter in the radial artery of their right arm. This is the standard of care for blood
pressure monitoring in this type of surgery. At the same times during the surgery that the
pressure is being measured from the aortic catheter, the pressure will be measured from the
catheter in the right radial artery.
Inclusion Criteria:
- Adult patients, age 40-80, who are scheduled to undergo elective coronary artery
bypass graft (CABG) surgery at the University of Iowa Hospitals and Clinics.
Exclusion Criteria:
- off-pump CABG surgery, emergency cases, patients who already have a balloon pump or
major valvular heart disease, and if preoperative PWV is not obtainable for any
reason.
We found this trial at
1
site
Iowa City, Iowa 52242
Principal Investigator: Kenichi Ueda, MD
Phone: 319-384-5718
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