Heart and Blood Pressure Study: The Effect of Aortic Impedance on Myocardial Relaxation

Official Title: “The Effect of Aortic Impedance on Myocardial Relaxation”

Does dilation of blood vessels (vasodilation), which decreases aortic stiffness, have a greater effect on heart myocardium relaxation (diastole) than vasodilation which affects mean pressure equally without improving aortic stiffness?

60 subjects, 30 with hypertension and 30 without will attend two visits to the GCRC. At each visit, pulsatile hemodynamics (by using tonometry—a non-invasive means to obtain arterial pressure tracings) and Doppler tissue imaging relaxation velocity (a measurement of myocardial relaxation obtained by echocardiography) data will be collected before and after administration of vasodilator medication. At the first visit, each patient will receive an oral dose of the vasodilator hydralazine (does not effect aortic stiffness), and at the second visit each patient will receive intravenous nesiritide (does effect aortic stiffness). The relationship between timing of the reflected pulse wave and myocardial relaxation velocity will be studied at baseline and following administration of each vasodilator to determine if changing aortic stiffness has an impact on myocardial relaxation.

Intervention(s) in this Clinical Trial

• Drug: oral hydralazine and intravenous nesiritide
  • vasodilators

Primary Measures

• heart myocardium relaxation (diastole)
  • Time Frame: before and after administration of vasodilator medication
    Safety Issue?: No

Inclusion Criteria:

• Subjects over the age of 65

Exclusion Criteria:

• Have known or suspected coronary artery disease
• Have known or suspected left ventricular dysfunction
• Have significant valvular, infiltrative, pericardial, or congenital heart disease
• Have a resting systolic blood pressure < 100 mmHg
• Have had an adverse reaction to nesiritide or hydralazine
• Have a serum creatinine > 2 mg/dl at Visit 1

Gender Eligibility for this Clinical Trial: Both

Minimum Age for this Clinical Trial: 65 Years

Maximum Age for this Clinical Trial: N/A

Are Healthy Volunteers Accepted for this Clinical Trial?: Accepts Healthy Volunteers

Lead Investigator: University of Wisconsin, Madison Other

Overall Clinical Trial Officials and Contacts

Nancy K Sweitzer, MD, PhD Principal Investigator University of Wisconsin, Madison  

Information obtained from ClinicalTrials.gov on February 09, 2012

Link to the current ClinicalTrials.gov record. http://clinicaltrials.gov/show/NCT00204984

Study ID Number: 2004-382

ClinicalTrials.gov Identifier: NCT00204984

Health Authority: United States: Food and Drug Administration