A heart transplant is a major open-heart operation in which a failing heart is replaced with a healthy donor heart. Although the procedure is complex, the basic principle is straightforward: the diseased heart is removed, the donor heart is positioned in the chest, and the major blood vessels are carefully connected so that the new heart can begin circulating blood through the body.
*AI-generated image - for illustration only. Clinical accuracy is not guaranteed.
If you are preparing for heart transplant surgery, understanding what happens inside the operating room can make the process easier to follow. The operation generally involves general anesthesia, a chest incision, cardiopulmonary bypass, removal of the failing heart, attachment of the donor heart, and careful monitoring before the patient is transferred to intensive care.
How Long Does Heart Transplant Surgery Take?
Heart transplant surgery commonly takes around 4 to 6 hours, although the duration can be longer when the operation is technically complex or additional procedures are required.
The exact time depends on the patient's condition, previous heart surgery, whether a mechanical circulatory support device needs to be removed, and the surgical approach used.
The time spent in the operating room is only part of the overall transplant process. Preparation before surgery and monitoring immediately afterward add several more hours to the patient's hospital journey.
What Happens Before the Operation?
*AI-generated image - for illustration only. Clinical accuracy is not guaranteed.
Once a suitable donor heart becomes available, the patient is brought to the transplant centre as quickly as possible. The transplant team performs a final assessment to make sure the donor heart is suitable and that the patient is medically ready for the operation.
This can include blood tests, physical assessment and other checks. The donor heart itself is also carefully assessed before the transplant proceeds. If the team determines that the organ is not suitable or that proceeding would not be safe, the operation may be postponed.
Because a donor heart has a limited period in which it can safely be transplanted after removal from the donor, the surgical and transplant teams work under strict time constraints.
Step 1: General Anesthesia and Monitoring
Heart transplantation is performed under general anesthesia, so the patient is completely asleep and does not feel the operation.
Before and during surgery, the anesthesia and surgical teams place monitoring lines and tubes that allow them to continuously assess blood pressure, oxygen levels, heart function, fluid balance and other important measurements. A breathing tube is connected to a ventilator to support breathing during the operation.
Intravenous lines and, in most cases, a larger line in the neck are used to administer medicines and fluids. A urinary catheter monitors urine output during and after the operation.
Step 2: Opening the Chest
The surgeon usually accesses the heart through an incision in the middle of the chest. The breastbone, or sternum, is divided to provide access to the heart. This is known as a median sternotomy.
The surgical team carefully exposes the heart and the major blood vessels connected to it. The approach allows the surgeons to remove the failing heart and connect the donor heart in the same position within the chest.
Step 3: Connecting the Patient to a Heart-Lung Machine
Before the diseased heart is removed, the patient is connected to a cardiopulmonary bypass machine, also called a heart-lung machine.
The machine temporarily takes over the work of the heart and lungs. It removes carbon dioxide from the blood, adds oxygen and keeps blood circulating throughout the body while the surgeon works on the heart. This allows the surgeons to operate while the patient's own heart is disconnected from normal circulation.
*AI-generated image - for illustration only. Clinical accuracy is not guaranteed.
Step 4: Removing the Failing Heart
Once the patient is safely supported by cardiopulmonary bypass, the surgeon disconnects the diseased heart from the major blood vessels.
The exact surgical technique can vary. In a commonly used approach, most of the patient's heart is removed while a portion of the left atrium is retained. The remaining tissue provides a connection point for the donor heart.
The major vessels that need to be connected to the donor heart include the vessels carrying blood to and from the lungs and the aorta, which carries oxygen-rich blood from the heart to the rest of the body.
Step 5: Positioning the Donor Heart
The donor heart is placed inside the patient's chest in essentially the same anatomical position as the original heart. The surgeon then begins creating the connections between the donor heart and the patient's existing blood vessels and remaining heart tissue. The precision of these connections is critical because they establish the new pathway for blood to travel through the heart and lungs.
*AI-generated image - for illustration only. Clinical accuracy is not guaranteed.
Step 6: Connecting the Donor Heart
The surgeon carefully joins the donor heart to the patient's circulation. Depending on the surgical technique, the connections involve the donor heart's:
- Left atrial area, connecting with the retained portion of the recipient's heart and the pulmonary veins
- Vena cavae, which return blood from the body to the heart
- Pulmonary artery, which carries blood from the heart toward the lungs
- Aorta, which carries oxygen-rich blood from the heart to the rest of the body
Step 7: Restoring Blood Flow to the New Heart
Once the donor heart has been connected, blood flow is gradually restored. The transplanted heart often begins beating when circulation is restored. In some cases, the heart may require an electrical shock or medicines to establish an effective rhythm.
The surgical and anesthesia teams closely monitor the heart's function during this stage. They assess whether the new heart is pumping effectively and whether the circulation is stable.
Step 8: Coming Off the Heart-Lung Machine
When the surgical team is satisfied that the donor heart is functioning adequately, the patient is gradually taken off cardiopulmonary bypass.
The new heart then takes over the work of circulating blood through the body. The team continues to monitor blood pressure, heart function, oxygen levels and other important measurements while adjusting medicines as necessary.
Coming off the bypass machine is an important stage because it confirms that the transplanted heart can support the body's circulation without the machine.
Step 9: Closing the Chest
After the surgical team has confirmed that the new heart and blood vessels are functioning appropriately and bleeding is adequately controlled, the chest is closed.
Temporary drainage tubes may be placed around the heart and lungs to remove blood or other fluid that can accumulate after major chest surgery. A breathing tube usually remains in place while the patient is initially recovering in intensive care.
What Happens Immediately After Heart Transplant Surgery?
After the operation, the patient is transferred to the intensive care unit (ICU) for close monitoring. At this stage, the medical team monitors:
*AI-generated image - for illustration only. Clinical accuracy is not guaranteed.
- Function of the transplanted heart
- Blood pressure and circulation
- Oxygen levels and breathing
- Fluid balance and urine output
- Kidney function and other organ function
- Possible bleeding or other surgical complications
- Early signs of problems affecting the transplanted heart
What Happens to the Removed Heart?
The removed heart may be examined by the medical team to better understand the underlying heart disease and to assess the tissue when clinically indicated. The exact handling depends on the transplant centre and the medical circumstances.
Why Is a Heart Transplant Considered a Complex Operation?
Heart transplantation involves more than replacing one organ. The surgical team must temporarily take over the patient's circulation, remove the failing heart, connect a donor heart to several major blood vessels, restore circulation and then ensure that the new heart can function independently.
The procedure also requires coordinated work from cardiac surgeons, transplant physicians, anesthesiologists, perfusion specialists, nurses and other members of the transplant team. Cardiopulmonary bypass itself requires continuous monitoring of blood flow, oxygenation, blood pressure and temperature while it supports the patient during surgery.
The Bottom Line
Heart transplant surgery replaces a failing heart with a donor heart through a carefully coordinated open-heart operation. The patient is placed under general anesthesia and connected to a heart-lung machine while the surgeon removes the diseased heart. The donor heart is then positioned in the chest and connected to the major blood vessels and remaining heart tissue.
Once the connections are complete, blood flow is restored and the surgical team checks that the new heart is functioning properly before gradually taking the patient off cardiopulmonary bypass. The chest is then closed, and the patient is transferred to intensive care for close monitoring.
The operation itself may take around 4 to 6 hours, but the transplant journey extends well beyond the operating room. Recovery, rejection monitoring, anti-rejection medicines and long-term follow-up are essential parts of living with a transplanted heart.
