What is elevated right atrial pressure in a 4 month old infant and how dangerous is it?
"Baby with elevated right atrial pressure"
Dear "Baby with elevated right atrial pressure",
The heart has four heart chambers, two atria and two ventricles. The right atrium is the upper chamber on the right side of the heart. It receives unoxygenated blood from the body via the superior vena cava and inferior vena cava. Blood from the right atrium is pumped into the right ventricle below it. The blood then flows from the right ventricle to the lungs via the pulmonary artery to get oxygen. (1) The term atrial pressure represents the pressure in the atria or upper chambers.
The two things that affect the pressure in a heart chamber is the size of the chamber and the amount of blood in the chamber. (2) The pressure of a heart chamber changes as the amount of blood in the chamber changes. Through the different phases of the heart beat, blood is moved in and out of the heart chambers. The opening and closing of the valves between the chambers and the contraction and relaxation of the heart muscle is what controls the movement of the blood through the chambers. (2) This opening and closing of the valves is controlled by normal pressure changes in each heart chamber.
The pressure in the chambers of the heart changes according to phase of the heartbeat.
When the muscle of the right atrium is relaxed or not contracting, the pressure steadily increases due to the continual flow of blood from the body into the chamber. As the ventricle stops contracting and goes into the relaxation phase, ventricular pressure drops below atrial pressure. This change in pressure causes the valve between two chambers to open and the blood from the right atrium drains into the right ventricle. When atrial pressure builds up, the right atrium contracts and sends the remaining blood rushing into the right ventricle.
Therefore elevated atrial pressure is not a diagnosis but one of the hemodynamic changes in the heart that may be normal depending upon the phase of contraction. If the right atrial pressure is consistently elevated above the pressure that is expected this may be considered abnormal. A single abnormal finding is not a diagnosis of a heart condition. Typically one abnormality in the heart affects the functioning and dynamics of the other parts of the heart. Therefore the condition and functioning of the whole heart needs to be evaluated in order to diagnose a cardiac condition.
Through Echocardiography a pediatric cardiologist can tell you the position, size and motion of the chambers of the heart, the condition of the internal structures of the heart and the pressure on each side of the heart valves. (3) This additional information along with your child’s history and physical examination is needed in order know the significance and long term effects of elevated right atrial pressure.
Increased atrial pressure is one of a group of changes that may be found in certain heart conditions, but alone is not diagnostic of a particular condition. Heart defects resulting in abnormal or insufficient functioning of the valve, a malformation of the chambers or an abnormal opening between chambers can lead to increased blood volume in the right atrium and subsequent elevated right atrial pressure.
For example, a child with Pulmonary Stenosis has a malformation of the cusps of the pulmonic valve, which controls the flow of blood from the right ventricle. If the condition is severe, the right ventricular pressure increases and thickening of the right ventricular wall occurs also known as right ventricular hypertrophy. If the right ventricular hypertrophy is severe enough, right atrial pressure can increase. (3) Upon reviewing an Echocardiogram of a child with Pulmonary Stenosis all of these findings would be noted.
A consultation with a Pediatric Cardiologist can give you the information that you need about the status of your child’s heart as well as the “danger” of these findings. It is also important to remember the cardiac defects have different levels of severity. The expertise of a Pediatric Cardiologist is needed in order to interpret Echocardiogram results, to determine the significance of any findings, discuss long term effects and answer your questions.
I wish you and your 4 month old baby well and hope you find some clarification of your child's condition.
(1)Waley L, Wong D. Nursing Care of Infants and Children. 2nd ed. St. Louis Missouri:The C.V. Mosby Company.1983:1279.
(2)Tortora G, Anagnostakos N. Principles of Anatomy and Physiology. 4th ed. Sao Paulo, Sidney:Biological Sciences Textbooks, Inc. 1984:468.
(3)Betz C, Hunsberger M, Wright S. Family-Centered Nursing Care of Children. 2nd ed. Philadelphia, PA:W.B.Saunders Company.1994: 1310,1349.
Lisa-ann Kelly R.N., P.N.P.,C.
Certified Pediatric Nurse Practitioner
Advice About Pediatric Health Conditions