Blood Pressure (Hypertension)
by Dr. V.P. Nair
4 August 2015
Blood pressure (BP): refers to the arterial pressure. It is due to the pumping action of the heart and the pressure exerted by circulating blood upon the walls of blood vessels. During each heartbeat, blood pressure varies between a maximum (systolic) and a minimum (diastolic) pressure expressed as for example 130/80 millimetres of mercury (mmHg).
Hypertension means high blood pressure.
Hypotension means low blood pressure.
Types of Hypertension:
1. Primary hypertension: In around 95%, no definite cause of high blood pressure is found. This is called essential or primary hypertension.
2. Secondary hypertension: Secondary hypertension means secondary to an identifiable cause. This is rare and only 5% of hypertension belong to this category
Causes of Secondary Hypertension are as follows:
a) Chronic kidney disease
b) Disorders of the adrenal gland (pheochromocytoma, hyperaldosteronism ,
c ) Pregnancy when there is preeclampsia
d) Birth control pills, diet pills, some cold medications, and migraine medications
e) Narrowed artery that supplies blood to the kidney (renal artery stenosis)
g) Coarctation of aorta
h) Sleep apnoea
In most cases, there are no symptoms. Because there are no symptoms, people can develop heart disease and kidney problems without knowing that they have high blood pressure.
Malignant hypertension: Severe headache, nausea, vomiting, confusion, changes in vision, or nosebleeds may indicate severe and dangerous form of high blood pressure called malignant hypertension.
Check blood pressure several times before diagnosing hypertension. Blood pressure readings taken at home may be better. Take blood pressure correctly with a good BP set. Your doctor will perform a physical examination to look for signs of heart disease, damage to the eyes, and other organs.
Investigations include the following test:
Electrocardiogram, Echocardiogram, and exercise stress test.
Blood tests, urinalysis or ultrasound of the kidneys
The goal of treatment is to reduce blood pressure and lower risk of complications
1. Physical means: Eat a healthy diet, including low fat, low salt and high fibre food. Drink enough water.
Exercise regularly - at least 30 minutes of aerobic exercise a day.
Limit alcohol - one drink a day for women, two a day for men.
Limit salt - less than 1.5 gram per day.
Reduce or avoid stress. Try meditation or yoga.
Aim a healthy diet and body weight.
Keep the BMI <=23cm2/kg if possible
2. Medical Treatment: There are many different groups of medicines to treat high blood pressure. They are known as diuretics, beta-blockers, calcium channel blockers, Angiotensin Converting Enzyme Inhibitors (ACEI) and Angiotensin Receptor Blocker (ARB). There are many types of medications belonging to each group. Often, a single blood pressure drug may not be enough. You may need to take two or more drugs. If you have side effects, your doctor can substitute a different medication.
3. Renal denervation (RDN): RDN is the new treatment for resistant hypertension. A special catheter is introduced through the femoral artery in the groin and is threaded through the renal artery near each kidney. Once in place, the tip of the catheter delivers low-power radio frequency (RF) energy to modulate the surrounding sympathetic nerves.
4. Surgery: Rarely done for secondary hypertension.
Most of the time, high blood pressure can be controlled with medicine and lifestyle changes. Occasionally surgical correction is needed for secondary hypertension.
When BP is not well controlled, you are at risk for:
Bleeding from the aorta, the large blood vessel that supplies blood to the abdomen, pelvis, and legs
Chronic kidney disease
Heart attack and heart failure
Poor blood supply to the legs
Problems with your vision
Check Blood pressure regularly, especially if someone in your family has or had high blood pressure.
Adults over 18 should check blood pressure regularly.
Modify, treat, or control possible causes of high blood pressure.
Target BP levels:
a) Non-Diabetic- 140/90 mmHg or less
b) Diabetic- 140/80mmHg or less
c) Diabetic at greater risk 130/80 mmHg or less
- Dr. V.P. Nair, Cardiologist