Related Experiment Video
Updated: Jul 14, 2026

In vitro Assessment of Myocardial Protection following Hypothermia-Preconditioning in a Human Cardiac Myocytes Model
Published on: October 27, 2020
Cardiovascular responses during thermoneutral, head-out water immersion in patients with coronary artery disease
Lutz Schega1, Gunter Claus, Michael Almeling
1Department of Rehabilitation Science, Katholieke Universiteit Leuven, Leuven, Belgium.
Purpose:
Water is frequently recommended as a therapeutic medium for cardiac patients. Reports on the cardiovascular response to immersion often differ, however, depending, for instance, if full or partial immersion were considered. The purpose of this study was to examine the cardiovascular responses to 2 immersion protocols in 3 age and gender-matched groups of patients each with a specific coronary artery disease.
Methods:
Fifteen patients with coronary artery disease entered water using a stepwise immersion (STEP) protocol (5 stages in 15 minutes) and an immediate, complete immersion (IM) protocol (2 stages in 6 minutes). Cardiac indices were monitored by transthoracic echocardiography. The heart rate was generated from the electrocardiogram, and blood pressure was measured using a manual mercury manometer.
Results:
The end-diastolic volume, end-systolic volume, stroke volume, and cardiac output decreased during STEP but increased during IM. As a consequence, the preload on the heart was greater during IM. Changes in systolic blood pressure were comparable in the 2 situations. The immersion-related decrease of heart rate was seen during STEP, but not during IM. Nevertheless, the hemodynamic responses to the initial stages of STEP up to the ankle joint were quite similar to those observed during immediate immersion to the neck.
Conclusion:
The cardiovascular responses to IM and STEP differed between protocols and even among subgroups within the same protocol. The findings further suggest that isolated immersion of body extremities can be beneficial to patients with coronary artery disease as preliminary preparation before complete water immersion is undertaken.
Related Concept Videos
Exercise and Cardiovascular Response
Light to moderate physical activity initiates a series of interconnected responses in the body. The heart rate modestly increases in anticipation of the workout, followed by widespread vasodilation as oxygen consumption by skeletal muscles increases. This results in decreased peripheral resistance, increased capillary blood flow, and accelerated...
Decreased Body Temperature
Responses to Heat and Cold Stress
Assessing Body Temperature - Temporal Artery
Step 1: Perform hand hygiene and don a fresh pair of gloves to prevent cross-infection and ensure patient safety.
Step 2: Explain the procedure to the patient to establish trust. Clear communication establishes trust with the patient, ensures they understand what to expect, promotes cooperation, and enhances comfort during the procedure.
Step 3: Assess the patient's forehead...
Cardiac Output I:Effect of Heart Rate on Cardiac Output
Cardiac output (CO) refers to the total amount of blood ejected by one of the ventricles in liters per minute (L/min). In a resting adult, CO ranges from 5 to 6 L/min, adjusting according to the body's metabolic requirements.
Effect of Heart Rate on Cardiac Output
Cardiac output adapts to metabolic demands during stress, physical activity, or illness. The autonomic nervous system regulates heart rate via the sinoatrial node. The parasympathetic nervous system decreases heart rate...
Assessment of the Cardiovascular System I: Subjective Data
Initial Enquiry
Ask the patient about their primary concern and thoroughly explore all reported symptoms.
Medical History
Investigate past illnesses affecting the cardiovascular system, such as angina, anemia, rheumatic fever, congenital heart disease, stroke, thrombophlebitis, dysrhythmias, varicosities
Inquire about symptoms...
