What Is Septal Myectomy

Introduction

Septal myectomy is a procedure to thin the wall between the left side of the heart and the right side of the right, which becomes thick and slows down the blood flow in people with hypertrophic cardiomyopathy. 

Having a thin septum will also reduce the blood flow going backwards towards the upper chamber of the heart.

Who's able to get a septal myectomy?

Septal myectomy is a treatment used by people with hypertrophic cardiomyopathy, so what exactly is this condition?

Hypertrophic cardiomyopathy (HCM)

HCM is a genetic disease that affects the heart muscle, causing a mutation in the protein that allows the muscle in the heart to contract, making the heart wall become thick (hypertrophy). Slowing down the blood flow, and causing other heart problems, such as myocardial ischemia and mitral regurgitation.²

Symptoms and complications

HCM affects around 1 in 500 adults, causing you to feel fatigue, chest pains, palpitations, dyspnea and syncope. Rarely, but in more severe cases in death.^1,2

How do you prepare for septal myectomy?

To prepare for the septal myectomy, the doctor will give you some instructions on preparing for the surgery. These may include stopping particular medications, such as blood thinners, before the operation.³

Diagnostic tests and imaging

Before the surgery, your doctor will have to check the health of the heart:

• Echocardiography - determines the health of the heart, how thick the heart muscles are and the effect of the blood flow in the heart 
• Cardiac MRI - helps to look at the heart in more detail
• Blood tests - show the overall blood counts and whether there may be a need for blood transfusion during or after surgery
• Electrocardiogram - helps show the heartbeats

What is the procedure for septal myectomy?

Overview of the myectomy process

This is an open heart surgery and it does require anaesthesia for performing the procedure. There are different ways, but generally this would happen:^1,3

1. The surgeon makes a large incision in your chest, cutting through the breastbone allowing them to see the heart
2. They will next, put catheters into areas where the blood flow enters and exits your heart. Catheters are connected to a heart-lung machine, also known as the cardiac bypass machine, which allows the doctor to perform surgery with a beating heart
3. The surgeon will then take out the thick area of the heart’s septum and also repair the mitral valve if needed
4. They will next reproduce blood flow from the cardiac bypass machine, making sure the heart is beating again on its own
5. The breastbone is finally put back together, before closing the incision with sutures

The surgeons alongside the team, will make sure you are safe during the procedure and will constantly monitor you during the surgery. 

Myectomy techniques

• Subaortic
• Midventricular
• Apical - the thickened area of the heart is removed from the area near the tip of the heart^3,6

What happens after the procedure?

Immediate postoperative period

After the surgery, you will be sent to recover in the intensive care unit (ICU) and you may have a urine catheter or a chest drainage tube placed onto you for 24-48 hours. Most people will recover in the hospital in around 5 days.³ 

Complications 

Septal myectomy does have some complications that should be taken into consideration:

• Bleeding
• Atrial fibrillation
• Infection
• New-onset heart block - a type of arrhythmia requiring a pacemaker
• Fluid around the heart and lungs

What is the prognosis for people after septal myectomy?

Most people will experience relief in their symptoms of hypertrophic cardiomyopathy just a few days after the procedure. Some minor chest soreness can be experienced, but you should not have any severe pain. 

Septal myectomies do have high success rates, of about 94%, where people have experienced improvement in their symptoms after surgery. In the long term, people who had the procedure done had the same survival rates as the common population.^1,4

Are there any alternative treatments?

Patients with HCM can also have the option to have other treatments: 

Septal ablation

Septal Ablation, also known as Alcohol Septal Ablation, is a non-invasive technique that uses a catheter. In the long-term, studies show that there are improvements such as reduced mitral regurgitation, reduced pressure and size and reduced thickness of the heart. 

It has also been shown to be improving symptoms of heart failure. In comparison with septal myectomy, alcohol septal ablation is less invasive, needs less hospitalisation and has a shorter recovery time.⁵

What are the future directions for septal myectomy?

Emerging technologies in septal myectomy

In the future to improve the management of HCM through producing new personalised medical treatments and surgical tools. For instance, 3D printing of the heart is a technique that is widely used in surgical planning in patients with more serious conditions and diseases, such as cardiac cancer and aneurysms, but the use of 3D printing is still not well encouraged in HCM patients. Using 3D printing, will allow the doctor to have more detailed information about the geometry of the heart, which can allow for the doctor to have a more precise myectomy.⁷

Summary

Septal myectomy is an open-heart surgery that is used to treat HCM, so if you have HCM and your symptoms are affecting your daily life, it is good to speak with your doctor. 

Even though it is an invasive treatment, the success rates are high and there are a low number of complications. If myectomy is not something that you would like to do you and prefer a more non-invasive treatment, then alcohol septal ablation could be right for you, but it is a good idea to speak with your doctor about alternatives.