Related Experiment Video
Updated: Jun 27, 2026
Quantitative Autonomic Testing
Published on: July 19, 2011
Comparison of changes in heart rate variability and blood pressure during nitroglycerin administration and head-up
Tyler A Bosch1, Chris L Kaufman, Eric B Williamson
1School of Kinesiology, University of Minnesota, 1900 University Avenue S.E., Minneapolis, MN 55455, USA.
Objective:
To compare the changes in heart rate variability (HRV) and blood pressure (BP) between standard head-up tilt test (HUT) and nitroglycerin administration.
Methods:
Eighteen healthy men and women aged 23-58 years participated. HRV was assessed using standard methods at rest and during both tests. Heart rate and BP data were collected during a standard HUT (maximal tilt = 70 degrees for 10 minutes) and following administration of 0.4 mg of nitroglycerin during supine rest. Test order was randomized. Repeated measure ANOVA was used to determine if changes in HRV and BP were significantly different between treatments. Paired t tests were used to examine the change from baseline to treatment for each variable.
Results:
As compared to HUT, the change in diastolic blood pressure and HRV measures was significantly (P < 0.05) less after nitroglycerin administration. However, no significant differences (P > 0.05) in HRV variables were found between nitroglycerin administration and HUT during the 5th and 6th minutes of each test.
Interpretation:
Nitroglycerin administration and HUT caused significantly different changes in HRV over a ten-minute average. However nitroglycerin produced its maximal effect on HRV during the 5th and 6th minutes, which was similar to the effect caused by HUT at the same time. When using nitroglycerin administration to assess changes in HRV indices, the fifth and sixth minutes of testing will provide information similar to that of a HUT protocol.
Related Concept Videos
01:28Special considerations while measuring blood pressure
Monitoring Both Arms:
Monitoring BP in both arms during the initial assessment is advisable, as the systolic value may differ by five to ten mm Hg between arms. For subsequent BP assessments, use the arm with the higher reading.
01:16Antianginal Drugs: Nitrates and β-Blockers
Organic nitrates, such as nitroglycerin, play a pivotal role. Once metabolized, they liberate nitric oxide, a molecular marvel. Nitric oxide triggers guanylyl cyclase and augments cGMP production. This biochemical cascade orchestrates the relaxation of vascular smooth muscles, ushering in vasodilation and enhancing coronary blood flow. Administered...
01:26Exercise Stress Test
Exercise stress testing, commonly known as a treadmill test, is a noninvasive procedure used to evaluate cardiovascular function and diagnose heart conditions.
Definition
An exercise stress test measures the heart's response to exertion using a treadmill or stationary bicycle. Chest electrodes record the heart's electrical activity through an ECG, and blood pressure is monitored regularly.
Purposes
01:17Measurement of Blood Pressure
01:23Assessment of blood pressure in brachial artery(two-step method)
01:19Assessing Blood pressure using a doppler ultrasound
Pre-Procedural Guidelines for Doppler Ultrasound Blood Pressure Assessment:
Preparation of Equipment: