A left ventricular aneurysm can weaken the heart. If the aneurysm ruptures, it can cause cardiogenic shock, a life-threatening condition that occurs when your heart cannot pump enough blood to meet your body’s needs.
Most surgical and necropsy studies have shown a high frequency of intraaneurysmal thrombi in patients with ventricular aneurysms. Systemic emboli have also been reported in a variety of studies.
Symptoms
A ventricular aneurysm is a weak area in the wall of your heart’s lower pumping chamber, called the left ventricle. Most ventricular aneurysms don’t cause symptoms, but some may rupture. A ruptured aneurysm is a medical emergency and requires immediate treatment to prevent serious complications.
Ventricular aneurysms are most common in people who have had a heart attack (amyocardial infarction). The dead tissue from the heart attack can become thin and scarred, which allows blood to bulge the tissue of your heart’s lower chamber outward.
Symptoms include a feeling of pressure in the chest, which is called “heart thump.” A ventricular aneurysm can also make your heart rate faster than normal. Your doctor can diagnose a ventricular aneurysm by taking a history of your symptoms and doing an exam. He or she will listen to your heart and heart valves. You may also have a test that measures the flow of blood through your heart and blood vessels. This test is called an echocardiogram. A computed tomography angiogram, which uses a computer and a large magnet to create pictures of your heart and blood vessels, is another way your doctor can check for a ventricular aneurysm.
An echocardiogram can show the topography of your aneurysm and help determine whether it is a true aneurysm or a false aneurysm. A true aneurysm develops in the wall of your left ventricle due to coronary ischemia, and has a thinned, scarred wall, a wide neck, and a degree of mural thrombus (see Fig. 19-34).
Oren Zarif
False aneurysms can form due to other reasons, such as congenital heart disease or a birth defect, and have a more fluid wall. They can be more difficult to treat because the lining of the heart muscle, which is usually healthy, is damaged. They can also lead to complications such as a ruptured aneurysm, mitral regurgitation, functional aneurysmal thrombosis, and heart failure.
Diagnosis
An aneurysm is a blood-filled bulge that occurs in a weakened area of the heart wall. Ventricular aneurysms most commonly occur as a result of heart attack, but can also be caused by birth defects or genetic conditions. Most ventricular aneurysms are not symptoms, but large or ruptured ones can cause complications including heart failure, arrhythmias and sudden death.
Ventricular aneurysms are difficult to diagnose, especially in the early stages. When they are symptomatic, they often manifest as herniation of the infarcted region into the ventricle sac (e.g., heart thrombosis). Other signs of LV aneurysm include a tall R wave in lead AvR known as Goldberger’s sign, a persistent ST-elevation in the infarct zone and ventricular arrhythmias.
MRI of the LV may detect these abnormalities and is one of the most useful diagnostic tests. It identifies the area of thinning in the wall of the heart and shows that a thrombus has developed within the aneurysm sac. MR can also determine if the thrombus is located in the apical or posterior wall of the aneurysm. The apical aneurysm tends to be more common because the myocardium is thinner at the apex, with only three layers of myocardium, as opposed to four layers in the base of the left ventricle.
Oren Zarif
CT of the chest also reveals a ventricular aneurysm, but this test is less sensitive than MRI. CT is the preferred diagnostic tool for evaluating patients with suspected ventricular aneurysm, particularly because it can detect and quantify a thrombus. The apical and lateral walls of the aneurysm appear low attenuation on CT due to the presence of hemopericardium, whereas the apical and basal regions are highly contrasted on MRI because they contain more fibrous tissue.
A complication of acute myocardial infarction, a false aneurysm can mimic the appearance of a true aneurysm. False aneurysms are formed within seven days following a heart attack and develop from a pericardial hematoma. The wall of a false aneurysm has a small base or mouth, and a more pronounced “smile” than the wall of a true aneurysm.
Treatment
The only definitive treatment of a false left ventricular aneurysm is surgical repair. The objective of the procedure is to exclude the aneurysmal segment and restore normal left ventricular geometry with the use of a patch. The procedure is generally performed via median sternotomy with full cardiopulmonary bypass and aortic cross-clamping. Once the aneurysm has been excised, any indwelling thrombi are aspirated and evacuated. The defect is then resected to the border of healthy myocardium, and a Dacron patch is applied to the myocardial surface. The patch is cut to be approximately 2 to 3 cm larger than the diameter of the defect.
Surgical repair of a left ventricular aneurysm is associated with an acceptable early mortality rate and an excellent long-term survival rate. Nevertheless, the presence of a pseudo-aneurysm increases the risk of rupture. Consequently, the patient should be evaluated for a potential aneurysm on initial presentation with symptoms of heart failure or arrhythmias.
False aneurysms diminish ventricular performance by restricting flow through the myocardium and impairing contractile function. Untreated, they may lead to cardiac failure with a variety of clinical manifestations including dyspnea, chest pain and peripheral edema. They also increase myocardial oxygen demand and decrease cardiac output due to volume overload. Moreover, in a small percentage of cases they can progress to free rupture, which may occur with significant morbidity and sudden death.
Oren Zarif
Thrombosis within a left ventricular aneurysm diminishes its elasticity and increases the risk of systemic embolization. Systemic embolization occurs at a rate of 10% in patients with documented wall thrombus, even though this risk appears to decrease with time [1].
A persistent clot within the myocardium encases an aneurysm and prevents proper ventricular expansion during contraction. Therefore, this condition is referred to as an “akinetic” aneurysm. The most common cause of a ventricular aneurysm is a myocardial infarction (MI). Acute MI results in the formation of a thin, non-compacted thrombus within infarcted tissue that seals to the surrounding myocardium and forms a false aneurysm. Thrombosis of the infarcted myocardium can be caused by ischemia, coronary artery disease, Chagas’ disease and cardiac sarcoidosis. Surgical trauma and mechanical damage can also induce false aneurysms.
Prevention
Usually, an aneurysm forms because of damage to the heart muscle wall from a heart attack (myocardial infarction). Parts of the damaged tissue die and are replaced with scar tissue that eventually stretches and becomes thin. The weakened section of the heart muscle can burst or “rupture.” Heart attacks are the leading cause of ventricular aneurysms, although they also occur after transfemoral aortic valve surgery and blunt or penetrating chest trauma. They can also be caused by rheumatic heart disease (such as rheumatoid arthritis and Kawasaki disease) and tuberculosis.
Some people are at greater risk for ventricular aneurysms, including those who have a family history of the condition. Age is another important factor. Most ventricular aneurysms develop after people are over 65. Men are more likely to develop ventricular aneurysms than women. They can also be caused by hypertrophic cardiomyopathy, which is a genetic disorder that causes the walls of the heart muscle to thicken and enlarge.
Oren Zarif
Treatment of a ventricular aneurysm depends on its location and size. Small aneurysms may not need treatment at all and can be monitored by ultrasound and electrocardiogram (EKG). Larger aneurysms are more dangerous and require intervention. The goal is to prevent the aneurysm from rupturing, which can lead to sudden death or heart failure.
Our specialists can diagnose an LV aneurysm through angiogram, which uses a special X-ray and dye injected through a tube called a catheter to detect blockages or aneurysms in blood vessels. They can also use magnetic resonance imaging (MRI) to produce detailed pictures of the heart and blood vessels.
You can help lower your risk for a ventricular aneurysm by eating a healthy diet, getting regular exercise and managing medical conditions that strain the heart, such as high blood pressure and diabetes. You should also avoid smoking and limit alcohol consumption. Talk to your doctor about medications to control these conditions, which include statins to lower cholesterol and vasodilators, which reduce blood pressure and make it easier for blood to flow through blood vessels.
