Aortic insufficiency is a condition where the aortic valve in your heart doesn’t close tightly, allowing blood to leak backward into the left ventricle after each heartbeat. This means your heart has to work harder to pump enough blood forward to the rest of your body. The condition is also called aortic regurgitation, and it ranges from mild (barely noticeable) to severe (potentially life-threatening).
How the Valve Normally Works
Your aortic valve sits between the left ventricle, the heart’s main pumping chamber, and the aorta, the large artery that delivers blood to your body. Each time the left ventricle contracts, the valve opens to let blood through. Between beats, it snaps shut so blood flows in one direction only. When that seal is incomplete, some blood flows backward during the resting phase between beats.
That backflow forces the left ventricle to handle both its normal incoming blood from the lungs and the blood leaking back from the aorta. Over time, the extra volume stretches and thickens the ventricle walls. This remodeling can sustain normal function for years or even decades in chronic cases. But eventually the heart muscle can weaken, leading to heart failure.
What Causes It
The causes split into two broad categories: problems with the valve itself and problems with the aorta that surrounds it.
Valve-related causes include being born with a bicuspid aortic valve (two flaps instead of three), which is one of the most common congenital heart defects. Infections of the heart valve, known as infective endocarditis, can destroy valve tissue rapidly. Rheumatic heart disease, a complication of untreated strep throat, remains a major cause in developing countries and tends to affect younger patients.
Aorta-related causes include high blood pressure, which over time can enlarge the aortic root and pull the valve leaflets apart. Marfan syndrome and other inherited connective tissue disorders weaken the aorta’s structure. A traumatic chest injury or aortic dissection, a tear in the inner wall of the aorta, can trigger sudden, severe regurgitation.
Acute vs. Chronic: Two Very Different Experiences
Aortic insufficiency behaves very differently depending on whether it develops suddenly or gradually, and this distinction matters for understanding symptoms and urgency.
In the acute form, blood floods backward into a ventricle that hasn’t had time to adapt. Pressure inside the chamber spikes quickly, which can force fluid back into the lungs and cause pulmonary edema. People with acute aortic insufficiency often look and feel severely ill: rapid heart rate, low blood pressure, chest pain, shortness of breath, and cough. This is a medical emergency that resembles the rapid onset of heart failure.
The chronic form is a slow leak that may worsen over years. The left ventricle gradually enlarges to accommodate the extra volume, and this compensation keeps people symptom-free for a long time. When symptoms eventually appear, they typically include shortness of breath during exercise, feeling winded while lying flat, waking at night gasping for air, a pounding or racing heartbeat, and occasionally fainting or chest pain.
How It’s Diagnosed
A doctor may first suspect aortic insufficiency after hearing a characteristic heart murmur through a stethoscope. In chronic cases, blood pressure readings often show a notably wide gap between the upper and lower numbers (widened pulse pressure), because the backflow drops diastolic pressure while the ventricle pumps harder to compensate.
An echocardiogram, essentially an ultrasound of the heart, is the primary tool for confirming the diagnosis and measuring severity. The test can show how much blood is leaking, how enlarged the ventricle has become, and how well the heart muscle is pumping. Severity is graded based on several measurements:
- Mild: less than 30 mL of blood leaking per beat, with less than 30% of the pumped blood flowing backward
- Moderate: 30 to 44 mL leaking per beat, with 30% to 39% flowing backward
- Severe: 60 mL or more leaking per beat, with 50% or more flowing backward
When echocardiogram images aren’t clear enough, or when results don’t match your symptoms, cardiac MRI provides an alternative. MRI can directly measure the volume of blood leaking with high precision and is more reproducible than echocardiography. It also gives detailed images of the aorta and valve structure.
What Happens If It Goes Untreated
Mild aortic insufficiency carries relatively low risk. At two years, people with mild disease have an estimated mortality rate around 7%, which is close to what you’d expect from their age and other health conditions alone. But as severity increases, the numbers climb. People with severe, untreated aortic regurgitation face roughly a 15% mortality rate over the same two-year window.
What makes prognosis harder to predict is that severity alone doesn’t tell the whole story. Enlargement of the left ventricle, enlargement of the left atrium, reduced pumping strength, atrial fibrillation, and elevated levels of a heart-stress hormone called BNP all independently raise mortality risk. In some cases, a person with moderate regurgitation plus several of these risk factors faces a comparable or even greater mortality risk than someone with severe regurgitation alone.
Treatment Options
Monitoring Mild to Moderate Cases
If your aortic insufficiency is mild or moderate and you have no symptoms, treatment typically means regular monitoring with periodic echocardiograms to track whether the leak is worsening or the ventricle is enlarging. The interval between check-ups depends on severity, ranging from every few years for mild cases to annually or more often for moderate ones.
Managing Blood Pressure
High blood pressure makes aortic insufficiency worse by increasing the force the ventricle has to push against. If you have both conditions, blood pressure control is important. However, beta blockers are generally avoided because they slow the heart rate and lengthen the time the valve is closed between beats, which can actually increase the amount of backflow. Other blood pressure medications that relax blood vessels are typically preferred.
Valve Surgery
Current guidelines from the American College of Cardiology and American Heart Association recommend aortic valve replacement for people with severe aortic regurgitation who either have symptoms or whose left ventricle pumping function has dropped to 55% or below, even without symptoms. That 55% threshold matters because it signals the heart muscle is beginning to fail, and waiting longer makes outcomes worse.
Surgery involves either repairing the existing valve or replacing it with a mechanical or biological prosthetic valve. Mechanical valves last longer but require lifelong blood-thinning medication. Biological valves, made from animal tissue, eventually wear out and may need replacement after 10 to 20 years but typically don’t require long-term blood thinners. The choice depends on your age, lifestyle, and other health factors.
For people who need other types of surgery for unrelated conditions, having moderate-to-severe or severe aortic regurgitation raises the risk of complications during and after the procedure, including dangerously low blood pressure, abnormal heart rhythms, and heart failure. Patients whose pumping function is severely reduced, at 30% or below, face particularly elevated risk of death within 30 days of surgery. When possible, valve surgery is recommended before other planned procedures.
Living With Aortic Insufficiency
Many people with chronic aortic insufficiency live for years, sometimes decades, without symptoms. The key is staying on top of regular monitoring so that any changes in heart size or function are caught early. Exercise is generally safe and often encouraged in mild to moderate cases, though your cardiologist may recommend avoiding intense weightlifting or other activities that sharply spike blood pressure.
If you’ve been told you have a bicuspid aortic valve or a family history of connective tissue disorders like Marfan syndrome, periodic screening is especially important, since these conditions predispose you to both aortic insufficiency and aortic enlargement. Catching progression before symptoms develop gives you the best surgical outcomes and the greatest chance of preserving long-term heart function.