A blood pressure reading of 120 over 60 is an example of isolated diastolic hypotension
Most people are concerned about high blood pressure (hypertension) because it’s a known risk factor for heart disease. However, low blood pressure (hypotension) is also a problem, especially if it causes symptoms.
In a blood pressure reading, the number on top represents your systolic blood pressure and the number on bottom represents your diastolic blood pressure.
- 120/80 mm Hg is considered normal for healthy adults.
- 90/60 mm Hg or below is considered low blood pressure.
But what if your systolic blood pressure is normal (between 100-120), and your diastolic blood pressure is lower (60 or below)?
You are considered to have low blood pressure, and the condition is called isolated diastolic hypotension.
What is isolated diastolic hypotension?
Diastolic blood pressure refers to the pressure exerted during the resting phase of your heart when it receives its blood supply. With isolated diastolic hypotension, a lower diastolic pressure means the heart is not getting enough of its blood supply. And a lower blood supply means a lower oxygen supply.
While you may not experience any symptoms, your condition should be monitored closely because frequently getting this type of blood pressure reading could be bad for your heart. For example, low diastolic blood pressure can cause your heart muscles to become weak and increase the risk of heart failure. This risk is higher if you have coronary heart disease.
What are signs and symptoms of isolated diastolic hypotension?
If you have isolated diastolic hypotension, you may experience:
Persistent low diastolic pressure can cause symptoms of heart failure, including:
- Shortness of breath
- Heart palpitations
- Swelling of feet or ankles
- Confusion
- Sudden chest pain or shortness of breath are serious signs that require immediate medical help
For many people, having a low blood pressure of 90/60 mm Hg is normal and they may not experience any signs and symptoms. However, others may experience:
- Dizziness
- Falls
- Nausea
- Decrease in concentration
- Blurred vision
- Fainting
What causes isolated diastolic hypotension?
Low diastolic blood pressure may be caused by:
- Alpha-blocker medications: These are known to decrease diastolic pressure more than systolic pressure. Many prostate medications contain alpha-blockers.
- Aging: Elasticity of the arteries decreases as people get older.
- High salt intake: Eating too much salt in your diet can decrease the elasticity of the arteries.
Causes of low blood pressure in general include:
- Prolonged bed rest.
- Heart problems:
- Heart valve problems
- Bradycardia
- Heart failure
- Endocrine problems (hypothyroidism or underactive thyroid)
- Pregnancy (in the first 24 weeks)
- Decreased blood volume due to:
- External injury
- Internal bleeding
- Dehydration
- Certain medicines used to treat:
- Hypertension
- Heart conditions
- Parkinson’s disease
- Erectile dysfunction
- Depression
- Anemia (a low hemoglobin level)
- Severe infections, such as septic shock
- Severe allergic reaction (anaphylaxis)
You may also get a low blood pressure reading when:
- You suddenly get up from a sitting or lying down position. This is called postural (orthostatic) hypotension.
- You sit after standing for a long time. This is called neurally mediated hypotension.