Related Experiment Video
Updated: Jul 14, 2026

Noninvasive Determination of Vortex Formation Time Using Transesophageal Echocardiography During Cardiac Surgery
Published on: November 28, 2018
Systolic time intervals
1Division of Cardiology, Ohio State University, Columbus 43210.
Abstract:
The systolic time intervals (STI) offer temporal description of the sequential phases of cardiac cycle which are influenced physiologically by the same variables as affect other measures of left ventricular (LV) performance. The STI hence offer a measure of ventricular function which augments other measures of ventricular performance. Because of the extreme sensitivity of this variable and the ease of its measurement the STI are well suited for studying the effect of pharmacologic agents upon the heart.
Related Concept Videos
Assessment of blood pressure in brachial artery(two-step method)
Special 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.
Cardiac Cycle
During the cardiac cycle, blood flow through the heart is regulated entirely by changing pressure gradients. This sequence of events begins with the heart in a state of total relaxation, known as mid-to-late diastole, during which blood passively flows from...
Correlation between ECG and Cardiac Cycle
A cardiac action potential originates in the SA node and spreads throughout the atria and the AV node in approximately 0.03 seconds. This results in the P wave in an ECG and triggers atrial contraction. The action potential is then briefly slowed at the AV node, allowing the atria to contract and fill the ventricles with blood before...
Measurement of Blood Pressure
Pulse
The pulse serves as a clinical indicator...

