Patient Guide Introduction
Heart valve surgery has proven to be quite successful over the past 30 years! Quality of daily life and general health are improved for the majority of patients who choose surgical treatment of heart valve disease. Knowledge of what to expect clarifies the process of going through a valve implant for you and your loved ones. On-X Life Technologies, Inc., makers of the On-X Prosthetic Heart Valve, has prepared this information guide to give you a better understanding of heart valve replacement procedures. Information in this guide provides a fundamental understanding of your surgery and choices you may have. Clinical terms that are used throughout this guide will appear in blue bold lettering when first used. The highlighted clinical terms are defined under Definitions. Because this guide will not answer every question, it is vital that you have good communication with your physicians prior to surgery. It is important that you prepare written questions for your physician to answer before you go to your appointments. Write down the physician's answers in the office so that you can refer to them later.
The heart is critical to our lives. It is a pump that delivers blood together with life-maintaining nutrients to all parts of our bodies. Just as with other pumps often used in daily life, the heart's continual function may require repair.
Figure 1. How Does the Heart Work: Interior of the heart1
The four heart valves are:
- Aortic Valve – Located between the left ventricle and the aorta (the main artery of the body). It prevents backflow of blood into the left ventricle.
- Mitral Valve – Located between the left atrium and left ventricle. It prevents backflow of blood into the left atrium.
- Pulmonary Valve – Located between the right ventricle and the pulmonary artery (the artery leading to the lungs). It prevents backflow of blood into the right ventricle.
- Tricuspid Valve – Located between the right atrium and the right ventricle. It prevents backflow of blood into the right atrium.
How does the heart work? It consists of four chambers (two atria and two ventricles) that beat regularly to push blood through the body and lungs (Figure 1). The flow of blood into and out of these chambers is regulated by four heart valves: two of the valves are located between the upper (atrial) and lower (ventricular) chambers, and two are located between the ventricles (lower chambers) and arteries (vessels that carry blood away from the heart). These valves open and close to regulate blood flow, opening to allow forward blood flow and closing to prevent backward blood flow. Without these valves working properly, the heart could not work effectively.
Figure 2. Blood Flow Path Through the Heart2
Right Heart receives blood from the body and pumps it through the pulmonary artery to the lungs where it picks up oxygen.
Left Heart receives oxygen-rich blood from the lungs and pumps it through the aorta to the body.
This figure is reproduced with special permission from The American Heart Association, Your Heart and How It Works, © 2005 www.americanheart.org
Blood is brought to the right atrium of the heart from all parts of the body through the veins. Contraction of this atrium pushes the blood through the tricuspid valve into the right ventricle. From there, contraction of the right ventricle pushes the blood through the pulmonary valve into the pulmonary artery and the lungs, where carbon dioxide is exchanged for oxygen. The blood then flows back to the left atrium of the heart from the pulmonary veins. Contraction of the left atrium occurs at the same time as the right atrium and causes the blood to enter the left ventricle through the mitral valve. The blood is then pushed out of the left ventricle through the aortic valve into the aorta and the whole body. Left ventricle contraction occurs at the same time as right ventricle contraction (Figure 2).