Open heart surgery involves opening the chest, usually by cutting through the breastbone, to allow a surgeon direct access to the heart muscle, valves, or major attached vessels. Most often, the procedure requires the use of a heart-lung bypass machine, which temporarily takes over the function of the heart and lungs.
This machine circulates and oxygenates the blood, allowing the surgical team to operate on a still, bloodless heart. Open heart surgery is reserved for serious conditions where less invasive methods are not possible or would not provide a durable repair. The necessity for this major operation is determined by the severity, complexity, and specific location of the heart problem.
Addressing Blocked Arteries
The most frequent reason for open heart surgery is Coronary Artery Bypass Grafting (CABG), commonly known as bypass surgery. This procedure treats Coronary Artery Disease (CAD), a condition characterized by the build-up of plaque within the arteries that supply oxygen-rich blood to the heart muscle. When these coronary arteries become severely narrowed or completely blocked, the heart muscle is starved of oxygen, which can lead to a heart attack.
During CABG, the surgeon takes a healthy blood vessel, often a segment of a vein from the leg or an artery from the chest wall, and uses it to create a new path around the blockage. This graft connects the aorta to the coronary artery at a point beyond the obstruction, effectively “bypassing” the diseased section and restoring proper blood flow to the heart muscle.
Bypass surgery is recommended over less invasive options, such as placing a stent, when blockages are numerous, involve multiple vessels, or are located in a critical area like the left main coronary artery. Patients with three-vessel CAD achieve better long-term outcomes with CABG. While a stent can open a single blockage, open surgery provides a more complete and durable solution for widespread disease by addressing multiple blockages simultaneously.
Repairing and Replacing Internal Structures
Open heart surgery is also required to fix defects within the heart’s internal machinery, primarily involving the valves and the septal walls. Heart valve surgery is performed when one or more of the four valves—aortic, mitral, pulmonary, or tricuspid—malfunction due to stenosis (a narrowing that restricts blood flow) or regurgitation (a leak that allows blood to flow backward).
To correct these issues, the surgeon may either repair the existing valve by trimming, patching, or reattaching leaflets, or replace it entirely with a mechanical or biological prosthetic valve. This work necessitates direct access to the interior of the heart and is often done on-pump, with the heart stopped and the patient connected to the heart-lung machine. This stable, bloodless surgical field allows for the precise suturing and manipulation required.
Open surgery is also used to correct certain congenital defects present from birth, such as Atrial Septal Defects (ASD) or Ventricular Septal Defects (VSD). These defects are holes in the walls separating the heart’s chambers, causing blood to mix and compromising efficiency. A surgeon accesses the septal wall to close the hole, often with a synthetic patch. Complex congenital conditions, such as Tetralogy of Fallot, also require open surgery to correct multiple structural abnormalities and reroute major vessels.
Correcting Issues with the Aorta and Major Vessels
Open heart surgery addresses conditions involving the aorta, the body’s largest artery, which originates directly from the heart. Conditions affecting this major vessel, particularly near the heart, require the comprehensive access provided by open surgery. These procedures are distinct from CABG, which addresses the smaller coronary arteries.
Open repair is necessary for Aortic Aneurysms—a ballooning or weakening of the aortic wall that can lead to rupture. It is also the standard treatment for Aortic Dissection, a life-threatening emergency where a tear in the inner layer of the aorta causes blood to rush between the layers. When a dissection occurs in the ascending aorta, the section closest to the heart, immediate open heart surgery is required.
During the open procedure, the damaged section of the aorta is removed and replaced with a synthetic tube graft made of material like Dacron. While less invasive endovascular techniques exist for aneurysms further from the heart, the complexity and high risk associated with ascending aortic pathology mandate the direct visualization and control of open surgery.
The Factors Determining Surgical Necessity
The decision to proceed with open heart surgery is based on a patient’s overall profile and the nature of the cardiac problem. It is chosen when minimally invasive alternatives are deemed inadequate or unsafe for the specific pathology. Surgeons consider the complexity of the disease, recognizing that open heart surgery provides direct access and the flexibility to address multiple issues simultaneously, such as valve repair and bypass grafting.
A patient’s overall health, including age, heart muscle strength, and the presence of other medical conditions like diabetes, is considered. While a healthier patient may be a candidate for a less invasive procedure, open surgery is often the safer, more comprehensive option for complex anatomy or when multiple procedures are needed. The goal is to choose the method that offers the most durable, complete, and reliable long-term result. Open heart surgery provides the surgeon with the best possible visual field and access to perform intricate, life-saving repairs, making it the necessary choice for the most challenging cardiac conditions.