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.
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.
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).
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 and may or may not have symptoms.
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%.
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.
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 to be 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. 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.
Grade 4
Grade 4 shares all the characteristics of Grade 3. However, 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
While some people with grade 1 diastolic dysfunction are asymptomatic, others may experience symptoms, such as:
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
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.
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.
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)
Other risk factors include:
SmokingAlcohol consumptionA diet high in animal fats, trans fats, simple carbohydrates, and processed foods in generalA sedentary (inactive) lifestyleChronic 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.
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.
