Introduction to CVD Flashcards
What do I need to know about Cardiovascular Disease?
What causes cardiovascular disease? – Line between causes and risk factors are quite blurred, but:
- Genetic
- Dietary
- Diabetes
- Sedentary lifestyle
- Smoking
- Age
- Sex
- Obesity
- Hypertension
- Stress
- Poor dental health - can cause more infection.
Think about which organs and tissues may be affected? The coronary vessels are impacted which are the ones which supply the blood to the heart. It tends to affect more men then women.
How does Smoking affect CVD?
Smoking cigarettes, specifically the nicotine in cigarettes, is the leading cause of premature death from cardiovascular disease. It is specifically the nicotine creating the issue.
What does smoking do to the heart?
- Heart rate and blood pressure are elevated - eg when inhale, which kicks off other reactions
- Blood flow from the heart is reduced, and reduced blood flow to the brain as a result increases stroke risk
- Blood vessels are damaged – nicotine predisposes the vessels to atherosclerosis (it attracts inflammatory cells to the endothelium of vessels, and induces endothelial dysfunction)
- Overall less oxygen reaches the body’s tissues
- Clot risk is increased – damaged blood vessels combined with reduced blood flow
Vaping - does vaping pose the same level of risk to the heart? What research is available about this? Vaping retains the nicotine…..
How does Diabetes affect CVD?
Diabetes and insulin resistance are specific risk factors for heart disease
Together they promote a specific kind of heart disease – diabetic cardiomyopathy – where defects in heart cell function cause heart muscle dysfunction.
This is not the only kind of cardiovascular disease that affects diabetics – they are still vulnerable according to age, diet, environmental and social factors to the broader causes of heart disease.
What is insulin resistance?
* Predisposing factor e.g. obesity, CVS disease, PCOS, which means
* Muscle, fat and liver cells less sensitive to insulin, whicih means
* Body cannot efficiently utilise glucose
How does diet affect CVD?
The main ‘culprit’ foods of heart disease are well known and they all set up an inflammatory environment in the body:
* Salt
* The ‘Western’ diet – high in saturated fat, red meat, processed carbohydrates; low in wholegrains, fruits and vegetables
* Alcohol
* Saturated fat
Factors feeding into inflamation - so obesity plays its role, homocyestine, disruption to the gut microbiome, saturated and trans fats, increased glycaemic load
Does high cholesterol CAUSE cardiovascular disease or is it a SYMPTOM - controversial.
* Research shows hypercholesterolaemia and atherosclerosis are connected, but not definitively shown that cholesterol is a cause.
* Is high saturated fat intake causative of high cholesterol and so increased risk of heart disease? And are dietary carbohydrates rather than fats the key risk factors for hypercholesterolaemia and heart disease?
Vitamin D and heart disease
There is some evidence of protective and beneficial effects of vitamin D on cardiovascular health. Consider, however, the chicken and egg effect – is the lifestyle causing low vitamin D more to blame on the predisposition to and development of heart disease, or is it the low vitamin D causing the heart disease first? Thinking point: what lifestyle factors lead to vitamin D deficiency?
A few elements of cardiovascular disease that have been shown to have potential links to vitamin D deficiency:
Endothelial function, arterial stiffness, plaque formation, peripheral vascular disease.
How does aging affect CVD?
Older adults are more predisposed to heart disease due to an array of factors, as well as complicating factors such as potential diabetes and hypertension:
Causes:
* Increased oxidative stress
* Inflammation leading to fibrosis and hypertrophy (repair but not well)
* Apoptosis - cell death
* Overall myocardial deterioration
Processes:
* Systolic and diastolic dysfunction - more likely as get older
* Electrical dysfunction leading to arrhythmia
How does a sedentary lifestyle affect CVD?
It is widely known that a sedentary lifestyle is a risk factor for the development of cardiovascular disease, but why?
- Reduction in cardiac output and peripheral vascular resistance leads to hypertension
- Decrease in insulin sensitivity
- Decrease in vascular function
- Increased oxidative stress
- Promotion of low grade inflammatory cascade
- Increased blood triglycerides
- Reduced HDL cholesterol
But – remember that even individuals who undertake frequent exercise and lead active lifestyles may develop cardiovascular issues – genetic/hereditary issues may arise regardless
What is hypertension as a process of CVD?
Hypertension (high blood pressure) is diagnosed if blood pressure readings on two separate days are both showing a systolic measurement of 140mmHg and/or a diastolic measurement of 90mmHg
Blood pressure is the force that blood circulating against the walls of the body’s arteries exerts - mechanically simple
Risk factors divide into those you can address (modifiable) and those which are fixed (nonmodifiable)
Modifiable
* Unhealthy diet, alcohol and smoking
* Sedentary lifestyle
* Being overweight or obese
Non-modifiable
* Family history of high blood pressure
* Being over 65 years old
* Co-morbidities such as diabetes or kidney disease
Diagnostically, hypertension is a disease but its impacts are so far reaching it can be useful to consider how this condition acts as a process and impacts on other systems.
As well as the heart itself, the development or process of hypertension (smoking, poor diet, sedentary lifestyle) all build on each other and create negative impacts on the kidneys, eyes and peripheral vasculature (fingers, toes etc).
What is the Atherosclerotic process?
The current understanding of atherosclerosis is as follows:
* patchy focal disease of the arterial wall.
* fatty streaks develop
* foam cells filled with lipids develop
* foam cell death causes lipid pools to appear
* smooth muscle cells proliferate in the plaque
* growth of plaque occludes/ blocks the vessel
It is important to distinguish between correlation and causation when considering factors contributing to the development of atherosclerosis.
Consider the following examples:
* High cholesterol has not been conclusively demonstrated to CAUSE atherosclerosis, even if present in elevated levels in patients with the condition
* Smoking has proven actions which may damage blood vessels, but a higher percentage of smokers belong to a socioeconomic demographic (impacting lifestyle) where there are numerous other factors that may also contribute to cardiovascular disorders – is it possible to definitively say smoking is causative in this case?
How do processes connect for heart disease?
Consider the Iinterconnection of processes – causes, results and risks.
How do processes connect? Can you think of more factors leading into ischaemic (coronorary) heart disease, and
organs that might be affected by heart failure?
Atherosclerosis, inflammation and hypertension can all combine to create heart disease, increasing risk for heart failure and then impacting the brain, lungs, kidneys and bone marrow…