What Happens During Open Heart Surgery? Procedure, Risks, and Recovery

Open heart surgery is one of the most important

advances in modern medicine and has helped

save millions of lives worldwide. It is commonly

performed to treat serious heart conditions such as blocked coronary arteries, damaged heart valves, congenital heart defects, and certain

diseases affecting the aorta. Although hearing

the term “open heart surgery” may sound

frightening, advances in surgical techniques,

anesthesia, and postoperative care have made

these procedures safer and more successful

than ever before (1,2).

Understanding what happens during open heart

surgery can help patients and families feel more

informed and prepared before the procedure.

What Is Open Heart Surgery?

Open heart surgery refers to operations in which surgeons open the chest to directly

access the heart. In many cases, the heart is temporarily stopped while a machine

called a cardiopulmonary bypass machine, or heart-lung machine, takes over the job

of circulating oxygen-rich blood throughout the body (1).

There are several types of open heart surgery. One of the most common is coronary

artery bypass grafting (CABG), which improves blood flow to the heart by bypassing

blocked coronary arteries. Other procedures include heart valve repair or

replacement, correction of congenital heart defects, and surgery involving the major

blood vessels connected to the heart (2).

What Happens During the Procedure?

Anesthesia and Preparation

Before surgery begins, the patient receives general anesthesia to ensure they

remain asleep and pain-free throughout the procedure. The surgical team monitors

blood pressure, oxygen levels, breathing, and heart rhythm continuously during the

operation (4).

Opening the Chest

The surgeon usually performs a median sternotomy, which involves making an

incision through the breastbone to access the heart. Once the chest is opened, the

heart and surrounding structures become visible to the surgical team (1).

Using the Heart-Lung Machine

For many open heart procedures, the patient is

connected to a heart-lung machine. This machine

temporarily performs the work of the heart and

lungs by pumping oxygenated blood through the

body while the heart is stopped, allowing

surgeons to safely perform delicate repairs (2).

Repairing the Heart

The exact procedure depends on the patient’s condition. During CABG surgery,

surgeons use healthy blood vessels from the leg, arm, or chest to bypass blocked

arteries. In valve surgery, damaged valves may be repaired or replaced with

mechanical or biological valves (1).

Restarting the Heart

After the repair is completed, the heart is restarted and carefully monitored to ensure

normal function. The patient is gradually disconnected from the heart-lung machine

once the heart is functioning properly again (2).

Closing the Chest

Finally, the breastbone is closed using surgical wires, and the skin incision is closed

with sutures or staples. The patient is then transferred to the intensive care unit

(ICU) for close monitoring during the early stages of recovery (4).

Risks and Possible Complications

Like all major operations, open heart surgery carries certain risks. However,

complication rates have decreased significantly due to improved surgical techniques

and perioperative care (1).

Possible complications include:

Bleeding

Infection

Irregular heart rhythms

Blood clots

Kidney complications

Reactions to anesthesia

Stroke or neurological complications

Stroke is considered one of the most serious complications associated with cardiac

surgery. Researchers have found that reduced blood flow or the formation of tiny

emboli during surgery may contribute to neurological injury in some patients (3).

The risk of complications may be higher in older adults and in patients with diabetes,

previous stroke, atrial fibrillation, or peripheral vascular disease (3).

Recovery After Open Heart Surgery

Recovery begins immediately after surgery in the ICU, where the patient’s condition

is closely monitored. Many patients remain connected to a ventilator for several

hours until they can breathe independently again (5). Enhanced recovery programs are becoming increasingly important in cardiac surgery because they help reduce complications, shorten hospital stays, and improve overall recovery outcomes (2). These programs focus on pain control, early movement, respiratory exercises, proper nutrition, and patient education. Patients are usually encouraged to begin walking within a short period after surgery to improve circulation and reduce the risk of complications such as blood clots or pneumonia (5). Deep breathing exercises are also important to support lung

recovery.

Most patients stay in the hospital for approximately five to seven days, although

recovery time varies depending on the type of surgery and the patient’s overall

health (4). Complete healing of the breastbone may take several weeks, and many

patients require six to twelve weeks before returning to normal daily activities (5).

Cardiac rehabilitation programs are often recommended after discharge. These

structured programs combine supervised exercise, education, and lifestyle

counseling to help patients safely regain strength and improve long-term heart health

(4).

The Future of Cardiac Surgery

Modern cardiac surgery continues to evolve through minimally invasive techniques,

robotic-assisted procedures, improved monitoring systems, and enhanced recovery

pathways. Researchers are also exploring new methods to reduce neurological

complications and improve long-term quality of life after surgery (3).

Although open heart surgery remains a major operation, it has become significantly

safer and more effective over time. With proper medical care, rehabilitation, and

healthy lifestyle changes, many patients are able to return to active and fulfilling lives

after recovery.

References

1-Engelman DT, Ben Ali W, Williams JB, Perrault LP, Reddy VS, Arora

RC, et al. Guidelines for perioperative care in cardiac surgery: Enhanced

Recovery After Surgery Society recommendations. JAMA Surg.

2019;154(8):755-66.

2-Myles PS, McIlroy DR. Fast-track cardiac anesthesia: Choice of

anesthetic agents and techniques. Semin Cardiothorac Vasc Anesth.

2015;19(1):5-16.

3-Ferrante MS, Pisano C, Ravera F, Speziali G. Cerebrovascular events

after cardiovascular surgery: Diagnosis, management and prevention

strategies. Kardiochir Torakochirurgia Pol. 2023;20(2):117-24.

4-American Heart Association. Heart procedures and surgeries

[Internet]. Dallas (TX): American Heart Association; 2025 [cited 2026

May 7]. Available from: https://www.heart.org/en/health-topics/heart-

attack/treatment-of-a-heart-attack/cardiac-procedures-and-surgeries

5-Cleveland Clinic. Open heart surgery: Procedure details and recovery

[Internet]. Cleveland (OH): Cleveland Clinic; 2024 [cited 2026 May 7].

Available from: https://my.clevelandclinic.org/health/procedures/21502-

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