Grade 1 Diastolic Dysfunction: Symptoms, Treatments

Grade 1 diastolic dysfunction occurs when the left lower chamber of the heart (the left ventricle) has trouble relaxing in between beats because it has stiffened over time. It interferes slightly with the heart's most important job—getting oxygen-rich blood to the rest of the body. 

When the left ventricle is stiff (restrictive cardiomyopathy), it cannot fill up completely, the way a brand-new balloon might be difficult to fill up with air because it is so tight. When this happens, the incoming blood backs up and congests nearby organs while the rest of the body doesn't get enough blood.

Verywell / Jessica Olah

How Your Heart Beats

A single heartbeat is divided into two basic phases, the systole (systolic) and the diastole (diastolic). During the systole phase, both ventricles contract, or squeeze. The left ventricle propels blood into the arteries for circulation throughout the body.

The right ventricle pumps blood into the lungs for reoxygenation. Next, during the diastole phase, both ventricles relax as they refill with blood that is delivered from the upper chambers of the heart (the left atrium and right atrium, known together as the atria). 

Grade 1 is mild. It is considered by some to be an expected or even a normal part of aging and is not usually cause for alarm. However, if grade 1 diastolic dysfunction were to progress to a more severe grade, it could be dangerous.

Grades of Diastolic Dysfunction

Doctors treating a patient with any level of diastolic dysfunction assign a grade that indicates how severe the condition is.

Grade 1

Grade 1 diastolic dysfunction is sometimes referred to as diastolic failure or heart failure with preserved ejection fraction (HFpEF). People with Grade 1 diastolic dysfunction have evidence of abnormal diastolic function, but have not yet developed any symptoms of heart failure.

Diastolic dysfunction does not necessarily translate to a diagnosis of heart failure, and preserved ejection fraction means that the percentage is within the normal range, or over 50%.

What Is the Ejection Fraction?

Ejection fraction describes the percentage of blood pumped out by a ventricle with each heartbeat. A healthy ventricle typically pumps out slightly more than half of its blood during each heartbeat, so that would be an ejection fraction of, for example, 55%. 

Grade 1 diastolic dysfunction is referred to as impaired relaxation. For patients with this grade of dysfunction, the diastolic filling of the ventricles is a bit slower than it should be, but other calculations are normal, and they have no symptoms of heart failure.

Some degree of dysfunction is expected in most people over the age of 65, but in one study, research using echocardiographic (cardiac ultrasound) measurements showed that up to 27.3% of the general population has some degree of dysfunction.

Grade 2

Grade 2 is considered pseudonormal, or nearly normal, and indicates a moderate state of disease. At this grade, as the left atrium fills with blood, the pressure is higher than it was in grade 1.

There may be early structural changes in the heart, such as enlargement of the atria, the ventricles, or both (hypertrophic cardiomyopathy). The left ventricle may also begin to function poorly during the contraction phase as well, and this is called systolic dysfunction.

Grade 3

Grade 3 indicates that pressure in the left atrium is significantly elevated and structural changes in the heart are more pronounced. This is a form of advanced heart failure.

However, this stage is considered reversible restrictive, meaning that the abnormalities can be temporarily reversed when a particular breathing method called the Valsalva maneuver is performed. This breathing method involves exhaling forcefully through the mouth while holding the nose tightly closed. In some cases, the force can stabilize the heart so that it returns to its normal rhythm.

Grade 4

Grade 4 shares all the characteristics of Grade 3, except that the Valsalva maneuver is no longer effective. This grade is only seen in very advanced heart failure, such as end-stage restrictive cardiomyopathy.

Based on the incidence of each grade, it is likely that most people (approximately 76.6% or more) with grade 1 diastolic dysfunction will not progress to higher grades of the condition.

Other tests may include:

B-type natriuretic peptide (BNP) or NT-proB-type natriuretic peptide (NT pro-BNP) blood testing, which reveals levels of a hormone and a nonactive prohormone, respectively. Both levels rise as a cardiac condition worsens.
Cardiopulmonary exercise testing (CPET or CPEX), also known as VO₂, or an oxygen consumption test, is a specific stress test that measures heart and lung responses to exercise.
Echocardiography uses sound waves, or ultrasound, to capture images of your heart. 
Nuclear testing measures the rate of blood flow to the heart.
Cardiac magnetic resonance imaging (CMRI), which uses magnetic fields and radio waves, provides images of soft tissue. It is more detailed than a CT (computed tomography) scan and can reveal or rule out stiffening of the heart muscle, an enlarged left atrium, or thickening of your heart walls.

Grade 1 Is Common

Grade 1 diastolic dysfunction is extremely common as people get older, and it may even be present in most people over the age of 60. It is usually mild, is often asymptomatic, and is not something doctors tend to worry about. 

Most doctors do not treat grade 1 diastolic dysfunction specifically. They will treat the conditions that could worsen it, such as high blood pressure, diabetes, and high cholesterol. Although it does progress over time, that does not mean diastolic dysfunction will ever become severe enough to reach grade 2.

Symptoms

Progression

People with true grade 1 diastolic dysfunction have no symptoms attributable to this condition. If any of the following symptoms occur, some other cause must be present:

Difficulty breathing when lying flat in bed
Waking up at night, gasping for breath
Enlarged neck veins from pressure within the heart
Wheezing or a persistent cough
Poor appetite and nausea
Fatigue
Weakness
Swelling in arms and legs
Heart palpitations

It is important to not self-diagnose. Some of these symptoms can be caused by other conditions, including temporary states like dehydration. Only a doctor can make a definitive diagnosis.  

Asymptomatic Grade 1 Diastolic Dysfunction

People with grade 1 diastolic dysfunction have no symptoms attributable to the diastolic dysfunction.

Because Grade 1 diastolic dysfunction can progress over time to overt heart failure, making heart-healthy lifestyle changes is very important in preventing progression of the condition. Clinicians monitor diastolic dysfunction and its progression by reviewing both symptoms and clinical findings. An X-ray or CT scan can reveal fluid buildup in the chest or an enlarged heart.

Risks

Age is the number one risk factor for developing grade 1 diastolic dysfunction. Perfectly fit and healthy people over 60 years of age can develop this condition. The condition is also more common in those who have been diagnosed with other conditions, including:

Hypertension (high blood pressure) 
Coronary artery disease (ischemic heart disease), in which the arteries of the heart have narrowed because of a build-up of fat and calcium particles
Atrial fibrillation (AFib), an irregular heartbeat due to chaotic electrical signals
Aortic stenosis, a narrowing of the aortic valve opening
Hyperlipidemia in which there are too many fat cells in the blood—LDL ("bad") cholesterol, triglycerides, or both
Low HDL ("good") cholesterol, which helps clear your body of LDL cholesterol
Type 2 diabetes, in which the body does not use insulin efficiently, resulting in high blood sugar
High levels of creatine (a by-product of muscle use) in the blood 
A chronically elevated heart rate
Obesity, or a BMI (body mass index) of 30 or above
Sleep apnea (sleep disorder in which breathing repeatedly stops and starts)

Understanding Blood Pressure

Blood pressure is measured by two numbers. The top number represents the pressure of each heartbeat (systolic pressure), and the bottom number indicates the amount of pressure in your arteries, in between heartbeats (diastolic pressure).

Other risk factors include:

Smoking
Alcohol consumption
A diet high in animal fats, trans fats, simple carbohydrates, and processed foods in general
A sedentary (inactive) lifestyle
Chronic stress

Smoking has a direct impact on the heart muscle, leading to the stiffening, thickening, and impaired filling that define diastolic dysfunction. Nicotine damages blood vessels and reduces oxygen levels in the heart, making it work faster and harder. 

Alcohol and sugar can both increase triglycerides (a type of lipid, or fat, found in blood) and HDL, worsening arterial damage. Similarly, refined grains and starches act like sugar in the body, with the same effects.

Saturated fats from animal sources also cause oxidative stress (free radical damage, which is like the human version of rust) and clog cardiac arteries, as do trans fats (particularly partially hydrogenated fats). This can lead to coronary artery disease, a risk factor for diastolic dysfunction. 

A sedentary lifestyle puts you at higher risk for heart disease.

Treatment and Prevention

For people with no diastolic dysfunction, or who are only at grade 1, the good news is that lifestyle changes can make a significant difference. This is an opportunity to reduce the risk of developing advanced heart failure and to improve your heart health. 

Lifestyle

The following measures lower the risk of developing or progressing with stage 1 diastolic dysfunction:

Quit smoking: If you need nicotine patches to succeed, make it temporary, and slowly taper down the dosage to zero. 
Monitor blood pressure, as well as cholesterol, triglycerides, and blood sugar: At high levels, all these factors can worsen diastolic dysfunction. 
Reduce stress: This is easier said than done, but practices such as yoga, meditation, hypnosis, walks, time in nature, and soothing music have all been shown to lower stress hormones and blood pressure.
Get seven to nine hours of sleep per night: Screen for and control sleep apnea.
Lose weight: Even a 5% reduction in weight can create a marked improvement in blood lipids and blood pressure, but aim for a BMI below 30, or better still, below 25. 
Exercise: Get 150 minutes per week of moderate physical activity or 75 minutes of intense exercise, which improves blood pressure, HDL and LDL cholesterol, triglycerides, cardiac strength, and endurance. Exercise can include walking, dancing, kayaking, swimming, cycling, or gym activities. Choosing something you enjoy makes you more likely to stick with it. The type of exercise is not nearly as important as frequency and consistency.

Eat many vegetables and up to three fruits per day: Make a point of getting leafy greens, such as broccoli, dark-green lettuce, and spinach, every day, which can protect arteries and lower blood pressure. Other fruits and vegetables combat oxidative stress and inflammation. Eat a wide variety of colors all week long, including orange, white, green, red, yellow, blue, and purple vegetables and fruits. 
Eat the right foods: Choose small quantities of whole grains, nuts, beans, peas, and avocados over processed foods to get heart-healthy fiber and fats that improve blood lipids. Severely limit most animal fats, including red meat, dark poultry meat and skin, egg yolks, cheese, cream, and all non–skim milk products.
Eat fatty fish three times a week: Non–fish eaters can eat seaweed, soy, walnuts, algae, flax or chia seeds, but will need greater quantities.  
Lower your fat intake: Eliminate trans fats, especially partially hydrogenated fats found in processed, snack, and deep-fried foods.

Avoid high-salt foods and added salt: Salt is sodium, which can raise blood pressure. 
Limit alcohol: Avoid or limit alcohol to one drink per day for women and two for men. 
Hydrate regularly: Consume 10–11 cups of liquid (soup, water, other non-sugary beverages) per day if you are female and 14–15 cups per day if you are male. If you are overweight, exercising, or in extreme heat, you will likely need more. Dehydration makes the heart work much harder and increases blood concentrations of fats and sugar. 
Eat three moderate meals per day and do not eat for several hours before bed.

Medications

Medications for conditions that put you at risk for diastolic dysfunction include those to control diabetes, blood pressure, LDL and HDL cholesterol, triglycerides, and obesity. If you are not already on these medications for the conditions above and your grade 1 diastolic dysfunction advances to a higher grade, your doctor may prescribe:

Diuretics, which reduce edema and lower blood pressure 
Beta-blockers, which reduce blood pressure and heart rate and can also stabilize arrhythmia (irregular heart rhythm)
Angiotensin receptor blockers or angiotensin-converting enzyme inhibitors, both of which relax veins and arteries, lowering blood pressure and making it easier for your heart to pump blood

A Word From Verywell

Even though it is considered a common part of the aging process, being diagnosed with grade 1 diastolic dysfunction may sound scary. The good news is that there are plenty of lifestyle changes and some well-researched medications to help you slow its progression and live a full and healthy life. 

Frequently Asked Questions

Diastolic dysfunction is diagnosed when a portion of heart muscle has stiffened and has trouble relaxing enough to fully fill up with fresh blood. As a result, blood can pool in nearby organs while the rest of the body lacks the oxygen-rich blood it needs.
Diastolic dysfunction develops with advanced age. Other contributing factors include obesity, diseases of the lungs known collectively as chronic obstructive pulmonary disease (COPD), high cholesterol and triglycerides, diabetes, high blood pressure, or preexisting heart conditions.
Most otherwise healthy people with grade 1 diastolic dysfunction have a normal life expectancy.
Mild diastolic dysfunction occurs when one or both lower chambers of the heart (ventricles) have a little trouble relaxing in between beats because they have become slightly stiff. Usually, this happens in the left ventricle and is typically referred to as grade 1 diastolic dysfunction.
While early-stage diastolic dysfunction is asymptomatic, as the condition progresses symptoms may appear. An early symptom is shortness of breath, especially during exertion. As it progresses, diastolic dysfunction may also lead to irregular heartbeat, fatigue, weakness, rapid heartbeat, chronic cough or wheezing, poor appetite, nausea, enlarged neck veins, and swelling in the arms and legs.

Search This Blog

Pulmonary Hypertension