Papillary Muscle Rupture

What is Papillary Muscle Rupture?

Papillary muscle rupture is a rare and highly dangerous event that often follows a heart attack or is a result of an infection in the heart lining. This sudden rupture can cause severe backflow of blood in the heart valve, which then leads to a life-threatening condition where the heart can’t pump enough blood to your body, along with fluid buildup in the lungs.

In the heart, there are 5 muscles called papillary muscles, which come from the heart walls. These muscles connect to the heart valve flaps via the chordae tendineae (like heart strings). Together, their function is to stop the backflow of blood from the ventricles by keeping the heart valves from collapsing or inverting during the heart’s contraction phase. Three of these structures are connected to the heart’s tricuspid valve, and two are connected to the mitral valve. When these papillary muscles stop working properly, it can cause blood to flow backward, which can lead to heart failure on either the left or right side of the heart.

The medical world first detected papillary muscle rupture back in 1948. It was first seen using a 2-dimensional ultrasound of the heart in 1981. Transesophageal echocardiography, a test that uses sound waves to create high-quality images of the heart and its blood vessels, was first used in 1985 to identify this condition.

The typical situation is a patient who had a heart attack affecting the artery that supplies the back of the heart. This patient then develops sudden heart failure between the second and seventh day after the heart attack. The functioning of the mitral valve is maintained by two of the papillary muscles. One of these muscles has two sources of blood supply, while the other only gets blood from the artery that is most often affected in a heart attack. Therefore, in most patients, it is this second muscle that is likely to rupture after a heart attack.

If a person does not get surgical treatment, the chances of survival are extremely low.

What Causes Papillary Muscle Rupture?

The most usual cause of a rupture in the papillary muscle, which is a part of the heart, is due to heart attacks. This rupture typically occurs from 2 to 7 days after the heart attack. It is more likely to happen after a type of heart attack where there’s a certain change in the heart’s electrical activity (known as ST-segment elevation), but it can also happen less commonly with heart attacks without these specific changes.

There are other reasons for this rupture, including injury, syphilis (a sexually transmitted infection), periarteritis nodosa (a disease that causes inflammation of the arteries), vegetating valvulitis (an infection that results in inflamed heart valves), myocardial abscess (an abscess forming in the heart muscle), medical procedures, and cocaine use.

Risk Factors and Frequency for Papillary Muscle Rupture

Papillary muscle rupture, which is a rare condition happening in 1% to 5% of patients with acute myocardial infarctions, or heart attacks. This rarity is mainly due to advancements in the quick identification and treatment of heart attacks via a process known as percutaneous coronary interventions, which helps to restrict the damage from lack of blood supply. However, if a rupture does happen, the chance of death is extremely high without surgical intervention. In fact, it’s estimated that about 50% of people could die within 24 hours of a complete rupture. Before the development of heart surgery techniques, this number was estimated to be between 80% and 90% within the first day. Interestingly, a study found that 82% of these ruptures happened in patients experiencing their first heart attack.

Signs and Symptoms of Papillary Muscle Rupture

Papillary muscle rupture is a complex medical condition that often occurs one week after a heart attack. It might be suspected in patients who experience sudden acute heart failure symptoms. This condition is particularly common in patients who have had their first heart attack that affects the lower wall of the heart.

Rapid and severe backflow of blood due to the failure of the papillary muscle can cause the atria or upper chambers of the heart to expand. This happens because of a sudden increase in atrial pressure. Coupled with overactivity in the region near or around the heart, and insufficient blood turbulence through the leaking valve, this condition can sometimes be hard to diagnose. This is because there is usually no stethoscopically audible heart murmur, which is a sound created by turbulent movement of blood between the atria and ventricle. However, in some cases, patients might have mid, late, or full-duration murmurs. The symptoms and physical signs of this condition are dependent on which valve is affected.

The most commonly affected part of the heart is the posterior-medial papillary muscle of the mitral valve, so symptoms of left-sided heart failure are common. These symptoms can include:

• Rapidly progressive water in the lungs
• Inadequate blood oxygen levels
• Low blood pressure due to failure of the heart to pump enough blood, commonly experienced as a sudden drop in blood pressure
• Chest pain in some cases

Given the immediate onset of low blood pressure due to heart failure and life-threatening complications, it is vital to promptly identify this condition as the death rates increases if immediate surgical intervention isn’t pursued.

Testing for Papillary Muscle Rupture

If a doctor suspects that you have a ruptured muscle (papillary muscle) in your heart and a sudden problem with a heart valve (acute valvular insufficiency), they can use two types of ultrasound: Transthoracic Echocardiography (TTE) or Transesophageal Echocardiography (TEE).

TTE happens on the outside of your chest. It can show if one of the heart’s valves is flopping in a way it shouldn’t during heartbeats, if there’s a ruptured muscle head moving erratically inside the heart, or if there’s something moving around that’s attached to the heart’s tendons. The ability of TTE to see these unusual things is usually between 65-85%.

If the results from TTE are not clear, doctors can use a more sensitive ultrasound, TEE. This type of ultrasound has a very high sensitivity range; it can identify abnormalities in 92-100% of cases.

Many patients are often too weak for invasive procedures, making TTE the go-to initial diagnostic method. Another test, called Doppler echocardiography along with color flow imaging, also assists in assessing the seriousness of the wrong flow of blood through the valve.

Ultrasound (echocardiography) is a better choice than a method called cardiac catheterization because doctors can diagnose the muscle rupture without a significant risk to the patient. In addition, if the test shows acute valvular problems, doctors strongly recommend surgery on the heart valve and restoring proper blood supply to the heart—people who receive this type of treatment show improvement in survival rates.

Treatment Options for Papillary Muscle Rupture

The primary treatment for a condition known as papillary muscle rupture is usually surgery, but other treatments like medications that remove excess water from the body (diuretics), treatments that lessen the work the heart has to do (afterload reduction), and oxygen therapy can be helpful initially. In severe cases, artificial methods may be used to help with heart function, such as a device called an intra-aortic balloon counter-pulsation.

In the past, there was a significant risk of death during surgery to repair the mitral value, one of the heart’s major valves affected by this condition. This risk was estimated to be around 20% to 25%. However, more recent research from 2008 found that the risk of death during these surgeries decreased to 8.7% when combined with another procedure known as coronary artery bypass grafting, which helps improve blood flow to the heart.

One thing doctors are still debating is whether repairing the mitral valve is better than completely replacing it. Currently, doctors tend to choose repair over replacement unless the disease has caused the death of tissue in the papillary muscles, which are responsible for controlling the function of the mitral valve.

Having coronary artery bypass surgery at the same time has been found to lead to better results, so it’s usually recommended.

Factors that can lead to worse results after valve repair surgery include long periods of stopping blood flow to the heart during surgery (prolonged cross-clamp times), sewing into weak tissue that’s starting to break down (friable necrotic tissue), and changes in the tissue after heart damage due to lack of blood supply (infarction).

In cases where the papillary muscle isn’t completely ruptured, doctors may delay surgery for 6 to 8 weeks after the heart attack to allow damaged tissue time to heal. Of course, this depends on the patient’s stability, and surgery may need to be done sooner if necessary.

What else can Papillary Muscle Rupture be?

: Other possible conditions that resemble the presentation of a heart issue may be:

• Severe left and right ventricular dysfunction, leading to cardiogenic shock
• Ventricular septal rupture
• Myocardial rupture on the free-wall

These conditions usually occur after a heart attack.

Severe left ventricular dysfunction can cause fluid in the lungs and decrease the blood flow to the organs. Severe right ventricular dysfunction may result in a rise in neck vein pressure, swelling in the limbs, low blood pressure, and clear lung fields. Right ventricular failure can also result in decreased blood flow to the left chambers of the heart, resulting in a low blood circulation state.

Ventricular septal rupture is associated with a 5% chance of death and is often observed with anterior infarction, which is a heart attack located at the front wall of the left ventricle. Unlike papillary muscle rupture which rarely occurs in the front region of the heart, septal rupture happens where the tissue has decayed, causing a left-to-right shunt, and a new pansystolic murmur. Rapid fluid buildup in the lungs is typically not seen.

Free-wall myocardial rupture is akin to septal and papillary muscle rupture, and often occurs in cases of small heart attacks and single-vessel disease. The rupture of the left ventricular wall is the most common and is observed within five days in 50% of patients and within two weeks in 90% of patients. The survival rate depends on whether the rupture is total or subacute, with almost a 100% fatality rate in complete ruptures due to its resultant abrupt onset of cardiac tamponade, a serious medical condition in which fluid builds up around the heart.

What to expect with Papillary Muscle Rupture

One research study found that in a group of 22 patients, 27% passed away during or after surgery. Meanwhile, almost half of those patients were still alive 7 years later. Another study included 55 patients and discovered that 24% of them died during or after their operations. The death rate was higher for patients who didn’t have surgery to restore blood flow to their hearts, at 39% compared to 9%. The third study followed 54 patients for 10 years and found that 35% of them were still alive, with 23% free of heart failure symptoms.

Possible Complications When Diagnosed with Papillary Muscle Rupture

• Heart-related shock
• Death