Hypertension and Cardiovascular disease risk factors Flashcards
What is hypertension?
Hypertension is high blood pressure (BP), defined as a persistent systolic blood pressure > 140mmHg, diastolic blood pressure > 90mmHg, or current use of antihypertensive medication.
What factors affect blood pressure (BP)?
cardiac output (CO), systemic vascular resistance (SVR), and the force exerted by the blood against the walls of the blood vessel.
What are some risk factors for hypertension?
age, family history, cigarette smoking, dyslipidemia, diabetes, obesity, excessive alcohol intake, sedentary lifestyle, psychosocial factors, and lower socioeconomic status.
How is blood pressure regulated?
Blood pressure is regulated by the sympathetic nervous system, the vascular endothelium, the renal system (including the Renin-Angiotensin-Aldosterone System), and the endocrine system.
How does the sympathetic nervous system (SNS) affect blood pressure?
Increased SNS activity increases blood pressure by increasing heart rate, cardiac contractility, noradrenaline release, inducing vasoconstriction in peripheral arterioles, and promoting renin release in the kidney.
What role does the vascular endothelium play in blood pressure regulation?
The vascular endothelium produces endothelin, a powerful vasoconstrictor, leading to increased blood pressure
How do the kidneys contribute to blood pressure regulation?
he kidneys control sodium excretion and extracellular fluid volume. Sodium retention leads to water retention, increased volume, and consequently, increased blood pressure. The Renin-Angiotensin-Aldosterone System (RAAS) is involved in this process.
How does the endocrine system influence blood pressure?
Stimulation of the sympathetic nervous system leads to the release of adrenaline, which increases cardiac output.
What are some complications of hypertension?
Complications include coronary artery disease (CAD), heart failure, stroke, left ventricular hypertrophy (LVH), peripheral vascular disease (PVD), and nephrosclerosis.
How do medications help manage hypertension?
Medications for hypertension work by dilating peripheral blood vessels, blocking adrenaline, decreasing renin secretion, dilating arteries, blocking the conversion of angiotensin I to angiotensin II, and inhibiting the movement of calcium across cell membranes.
Renin: When your body senses low blood pressure or low sodium levels, it releases renin. Renin acts like an alarm, signaling that something needs to be done to raise blood pressure.
Angiotensin I: Renin’s signal starts a process where a protein called angiotensinogen is transformed into angiotensin I. Think of angiotensin I as the first step in a chain reaction.
Angiotensin II: Next, angiotensin I gets converted into angiotensin II with the help of an enzyme called Angiotensin Converting Enzyme (ACE). Angiotensin II is like a superhero that swoops in to save the day. It’s a powerful vasoconstrictor, meaning it makes your blood vessels narrower, which increases blood pressure. This helps to push blood around your body more efficiently.
Aldosterone: But angiotensin II doesn’t stop there. It also tells your kidneys to hold onto more sodium and water, and it does this by triggering the release of a hormone called aldosterone. When your body holds onto sodium and water, it increases blood volume and cardiac output, which also raises blood pressure.
So, in simple terms, the RAAS is a team effort to increase blood pressure when it’s too low by narrowing blood vessels and retaining sodium and water.
