Cardiovascular Disease

Introduction to cardiovascular disease including pathophysiology and aetiology. 

Cardiovascular disease (CVD) is a wide term used to describe an array of disorders, ranging from diseases of the cardiac muscles, and the vascular system providing the heart, brain, and other vital organs (Gaziano, T., et al 2006). Some of these diseases can include coronary artery disease, electrical/conduction abnormalities, myocardial pump dysfunction and valve disease. It is currently the leading cause of death worldwide and it is estimated that almost 30% of all death worldwide is caused by CVD. The current aetiology of cardiovascular disease is based on two main assumptions: damage to endothelium of blood vessels causes lesions, local inflammation with mobilisation of white blood cells, lipoproteins and other substances, which lead to development of fibrofatty atherosclerotic plaques, therefore causing narrowing of arteries (stenosis or closure of the lumen); rupture of the atherosclerotic plaque with clot formation may lead to arterial occlusion thereby stopping blood flow (and oxygen) to a part of the heart causing damage to the heart muscle (myocardial infarction) or to a part of the brain (thromboembolic stroke) (Emul, M., & Kalelioglu, T. 2015).

Hypertension is a prevalent condition that affects over 20% of people in developed countries and it significantly increases the risk of health complications, including stroke, heart attack, heart failure, and kidney failure. By reducing blood pressure, the occurrence of stroke and myocardial infarction decreases (Nabel, E. G. 2003). Hypertrophic cardiomyopathy is the most common monogenic cardiac disorder and can cause sudden death from cardiac causes in children and adolescents (Nabel, E. G. 2003). coronary heart disease is suggested to be the largest cause of death in developed countries Nabel, E. G. (2003).  

Coronary heart disease (CHD), also known as coronary artery disease and ischemic heart disease is a common cardiac condition. CHD is characterised by the formation of atherosclerotic plaque within the arterial lumen (Shahjehan, R. D., et al 2024). this happens due to a build-up of cholesterol particles, and if left untreated can reduce and block blood flow and decrease oxygen to the myocardium (Adhikary, D., et al 2022). This can sometimes be asymptomatic. It can also encompass other conditions such as stable angina, acute coronary syndrome, and silent myocardial ischemia. Other conditions associated with increased CHD risk include chronic kidney disease, non-alcoholic fatty liver disease, and certain autoimmune disorders such as systemic lupus erythematosus and rheumatoid arthritis (Brown, J. C., et al 2020).  

CHD pathophysiology begins with the atherosclerotic plaque formation. Plaque is a fatty material that can narrow the arterial lumen and therefore reduces blood flow. The first part begins with the formation of ‘fatty streaks’ by subendothelial deposition of lipid-laden macrophages. When something happens to the heart the intima layer can break and monocytes move into the subendothelial area, where they become macrophages. These then take up oxidized LDL (low density lipoproteins) particles, leading to macrophage cell formation. Then the T cells become activated, and cytokines are released to help in the inflammatory process. Growth factors trigger smooth muscles, and they also oxidise LDL particles and collagen, deposit along with the activated macrophages, and increase the population as well. Therefore, subendothelial plaque develops. This plaque can either grow or become stable if no damage occurs. A fibrous cap forms if it becomes stable, and it will calcify over time. These lesions can become hemodynamically significant while time goes on. The myocardial tissue perfusion cannot be good enough and cause angina symptoms during increased demand, for example exercise. Some plaque can rupture and cause thrombosis.  

The risk factors for CVD include smoking, high blood pressure, high blood glucose, lipid abnormalities, obesity, and physical inactivity. There are two types of risk factors non-modifiable and modifiable risk factors. Non-modifiable risk factors of CHD include, but are not limited to age, gender, family history and genetic factors. Modifiable factors include, but are not limited to smoking, hypertension, dyslipidaemia, diabetes, obesity, physical inactivity, diet, stress, and alcohol. Both men and women are susceptible to CHD but their notable differences in the prevalence and age of onset between the sexes (Johns Hopkins Medicine Coronary Heart Disease). Men usually have a higher risk of developing CHD and are usually affected earlier in age than women, but women’s risk increases drastically after menopause (Mayo Clinic Coronary artery disease). Age is a significant factor in CHD development. As age increases so does your risk and it increases particularly after 35 years for both men and women. This age- related increase is partially due to the cumulative exposure to risk factors over time and the natural aging process of the cardiovascular system Brown (J. C., et al 2020). intake of more saturated fat could increase the risk of cardiovascular disease, a sedentary lifestyle increases weight, and hypertension is more likely to develop (Adhikary, D., et al 2022).  

 This essay aims to explore cardiovascular disease more specifically coronary artery disease and look at its epidemiology, pathophysiology, consequences and how medications and exercise can help patients experiencing cardiovascular disease. 

Epidemiology and consequences of cardiovascular disease 

The overall trend of CVD shows that whilst the absolute number of CVD deaths has increased from 12.1 million in 1990 to 20.5 million in 2021, certain demographics have decreased globally, those living in certain countries and age standardised death have both decreased (world heart foundation federate). In England, the deaths caused by CVD have halved since 2002 and has declined by more than 3/4s since 1961. However, the global burden of cardiovascular diseases has shown significant trends over recent decades. 

 In 2021, coronary heart disease alone accounted for 9,440,000 deaths worldwide and CVD caused 20.5 million deaths worldwide which accounts for one third of all death globally (world heart foundation federate). The distribution of CVD mortality is uneven across the globe, with eastern Europe and serval low and middle-income countries experiencing the highest rates. In the United Kingdom, there has been a substantial decline in CVD mortality, from 1,045 deaths per 100,000 in 1969 to 255 per 100,000 in 20192. However, disparities persist among UK nations, with Scotland reporting a higher death rate (326 per 100,000) compared to England (246 per 100,000) in 2019 (Adhikary, D., et al 2022). The reason for this decline in deaths caused by CVD could be due to improved medical interventions, primary and secondary prevention awareness, cholesterol management, blood pressure control and increased physical activity. These account for 49% of the decline (Mensah, G. A., et al. 2017). It is a consistent pattern for most high-income countries that stroke rate have been high, mostly haemorrhagic. This could be due to increased rates of diabetes and smoking and adverse lipid profiles. 

This is the same for coronary heart disease. The impact coronary heart disease model, validated across multiple countries, was used to assess what was contributing to the decline in CHD mortality from 1980 to 2000. It was found that approximately 47% of the decline was attributed to medical and surgical interventions, while 44% was due to reductions in major risk factors. Specific contributions included secondary prevention therapies (11%), treatments for acute MI or unstable angina (10%), heart failure treatments (9%), and revascularization for chronic angina (5%). Risk factor changes included reductions in total cholesterol (24%), systolic blood pressure (20%), smoking prevalence (12%), and physical inactivity (5%) (Mensah, G. A., et al 2017). Some of the ways to help prevent CV and CHD is to stop smoking, treat high blood pressure, exercise throughout the week, control blood sugars if you have diabetes, maintains a healthy weight through exercise and balanced diet and lower cholesterol (Torpy, J. M., et al. 2009).  

CHD has many physical consequences, these can include various complications such as angina which is where the blood flow to the heart is reduced and it cause pain and discomfort; myocardial infarction ( a heart attack ) which can be cause when the blood to the heart is completely blocked and then causes damage to the myocardium; heart failure due to the weakening of the heart over time; arrhythmias which is where the heart can develop an irregular heart rhythm. These are all physical consequences of CHD. (mayo clinic) (Dr Georgios Karagiannis) 

People living with CVD often experience a decreased quality of life due to the nature of the disease and they experience many physical limitations (Borkowski, P., & Borkowska, N. 2024). The psychological impact of CHD can be damaging and difficult. CHD can lead to experiences of anxiety and uncertainty and can be frequently accompanied by depression (Van Elderen, T., et al 1999). Living with CVD can cause worry about their lives and what to expect and can put a lot of pressure on their life, families, jobs and so much more. This can lead to stress. These psychological symptoms can then cause a lack of sleep, impair concentration, and decreases the ability to enjoy leisure activities. The limitations cause by the physical symptoms can cause the patients to feel frustrated, annoyed, and helpless (Borkowski, P., & Borkowska, N 2024). The other consequences of CHD are the economic factors and social factors. £19 billion is spent on CVD in the UK (Greenwood, D. C., et al 1996). 

Exercise, medications and recommendations for cardiovascular disease. 

Diagnosis of CV includes a wide range of tests and assessments and in some cases invasive procedures. Medical history and physical examination is the first step in any diagnosis. Then the common ways CV is diagnosed is using biochemical markers, ECG, coronary angiogram, CT, cardiac MRI, and exercise stress. 

heart disease can be managed through medicines, surgical treatments, and lifestyle modifications, such as eating healthy, physical exercise, maintaining body weight, avoiding smoking and less salt intake (Adhikary, D., et al 2022). There are many medical interventions that can be used for CV these can include medications, statins, angioplasty, cardioversion, ablation, pacemakers, and ICD. 

The management of CHD involves a multifaceted approach, including lifestyle modifications, pharmacological interventions, and, when necessary, revascularization procedures. Lifestyle modifications form the cornerstone of both primary and secondary prevention strategies, encompassing smoking cessation, adoption of a heart-healthy diet, maintenance of a healthy weight, and regular physical activity (Lopez, E. O., et al 2023).  

The pharmacological approach for managing CHD specifically is typically multi-faceted. Antiplatelet medications are commonly prescribed to mitigate the risk of blood clot formation (thrombosis). Statins can be used for lipid lowering. Beta-blockers can be prescribed to reduce myocardial oxygen demand and angiotensin-converting enzyme (ACE) inhibitors or angiotensin receptor blockers (ARBs) for blood pressure control and cardio protect are used. In cases where coronary arteries are significantly blocked more invasive procedures may be required. In patients with obstructive coronary disease, revascularization through percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG) may be necessary to improve symptoms and prognosis (Lopez, E. O., et al 2023). While this is said for CHD other heart diseases can used similar medications and treatment plans 

it is suggested that social support can act as a buffer towards chronic stress and benefit coping with illness. A systemic review agrees that those who are alone, disconnected, and isolated from other people have an increased risk of dying prematurely from CHD. On the same topic those who have a support system and people to confide in have an increased chance at survival and a better chance of recovery. It can also help with depression symptoms and feelings of anxiety therefore support groups and making sure patients have people to look after them and care is critical in their recovery. Some other techniques can include CBT (cognitive behavioural therapy) and group training (Albus, C. 2010). 

It has been shown that exercise training can help prevent and ameliorate cardiovascular disease. While exercise can reduce cardiovascular disease, it is also suggested that it can be instrumental in preventing chronic disease such as hypertension, dyslipidaemia, and diabetes mellitus. The key role of the cardiovascular system is the transportation of vital substances. More recently society has a more relaxed and less active lifestyle compared to previous generations, this has resulted in an increase of diseases. This is because a sedentary lifestyle increases the risks of cardiovascular disease. For example, ischemia is the leading cause of death as reported by the world health organisation based on the 2008 statistics. Diabetes and its increased correlation to cardiac disorders is also due to a sedentary lifestyle. So, while medications are helpful and constantly being developed exercise prescription can also help manage and decrease effects of cardiovascular disease (Gaziano, T., et al 2006).  

The benefits of exercise on the heart are now recognised as an integral part of cardiac patient care. Multiple findings show that exercise is beneficial to both those with various disease and those who are healthy. Moderate exercise done regularly produces cardio protection. And it is said that 30 minutes was enough weekly exercise to improve health, there are still many debates around the intensity, duration, and timing needed.  

Exercise can burn cholesterol by using it as an energy source. Exercise is related with both improved muscle function and heart strength and the opposite is said for those with a sedentary lifestyle. By lowering cholesterol, we can reduce the number of low-density lipoproteins (LDLs) which are elevated in most cardiovascular patients and can lead up to viscous blood and plaque build up in the arteries increasing odds of atherosclerosis. Therefore, by reducing this less damage to the heart will be caused (Dizon, L. A., et al 2013).  

Exercise used to aid in cardiac rehab (CR) can be either supervised or unsupervised, usually one being with a trainer and one being simple at home movements. usually, these sessions are aerobic in nature and involve static walking, cycling or circuit training. This will aid in strengthening the heart muscles (Anderson, L., et al 2016). It is suggested to slowly increase exercise to 30 minutes or more on most if not all days of the week, this can begin with brisk walking and then intensity should slowly increase with guidance. Doctors should also be maintaining appointments to check the patient is physically well enough to continue the exercise rate they are at. Walking is the preferred prescribed exercise to being with as its minimal impact and safe, it uses all the muscles and is also goof for getting outdoors or the mental boost of fresh air. The other recommended exercises are cycling and arm ergometry. All exercise however should be gentle impact to avoid injury. Resistance training is now also recommended for CHD patients, while aerobic exercise provides greater improvements for cardiovascular health, resistance training should also now be incorporated (Wise, F. M. 2010). Patients should not exercise if they have an absolute contradictions, for example acute myocarditis or pericarditis, uncontrolled heart failure, symptomatic serve aortic stenosis or unstable angina. They may be able to exercise if they have a relative contradiction but with great caution, for example Tachydysrhythmia or Bradydysrhythmia, Severe arterial hypertension (i.e. systolic blood pressure >200 mm Hg and/or a diastolic blood pressure of >110mm HG) at rest, Hypertrophic cardiomyopathy and other forms of outflow tract obstruction or Left main coronary artery stenosis (American College of Sports Medicine 2013).  

For patients with coronary heart disease specific food recommendations are suggested for example Mediterranean or DASH (dietary approaches for hypertension). This is because they hold key elements that aid in cardiovascular health. For example, it is recommended they consume 4-5 servings of fruits and vegetables a day at least, whole grains such as whole grain breads, cereals, pasta and brown rice instead of refined grains, lean proteins like chicken and turkey and incorporating oily fish like salmon and maceral. Legumes, nuts and seeds are also ideal. They should try to reduce the number of processed foods, refined grains, red meats and high saturated fat foods as these can increase cholesterol and blood sugars (Harvard Health: Heart-healthy foods: What to eat and what to avoid). 

Conclusion 

In conclusion, coronary heart disease remains a significant public health challenge despite improvements in mortality rates over recent decades. A comprehensive approach to management, including pharmacological treatments, lifestyle modifications, and structured exercise programs, is essential for improving health outcomes. As our understanding of CHD continues to evolve, integrating exercise prescription into standard care protocols, for example daily walks and low intensity resistance training to improve cardiovascular strength and health, will be required for improving patient health and reducing the overall burden of this disease.  

References 

Adhikary, D., Barman, S., Ranjan, R., & Stone, H. (2022). A systematic review of major cardiovascular risk factors: a growing global health concern. Cureus, 14(10). 

Albus, C. (2010). Psychological and social factors in coronary heart disease. Annals of medicine, 42(7), 487-494. 

American College of Sports Medicine (Ed.). (2013). ACSM's health-related physical fitness assessment manual. Lippincott Williams & Wilkins. 

Anderson, L., Thompson, D. R., Oldridge, N., Zwisler, A. D., Rees, K., Martin, N., & Taylor, R. S. (2016). Exercise‐based cardiac rehabilitation for coronary heart disease. Cochrane database of systematic reviews, (1). 

Borkowski, P., & Borkowska, N. (2024). Understanding mental health challenges in cardiovascular care. Cureus, 16(2 

Brown, J. C., Gerhardt, T. E., & Kwon, E. (2020). Risk factors for coronary artery disease. 

Dizon, L. A., Seo, D. Y., Kim, H. K., Kim, N., Ko, K. S., Rhee, B. D., & Han, J. (2013). Exercise perspective on common cardiac medications. Integrative medicine research, 2(2), 49-55. 

Emul, M., & Kalelioglu, T. (2015). Etiology of cardiovascular disease in patients with schizophrenia: current perspectives. Neuropsychiatric Disease and Treatment, 2493-2503.   

Gaziano, T., Reddy, K. S., Paccaud, F., Horton, S., & Chaturvedi, V. (2006). Cardiovascular disease. Disease Control Priorities in Developing Countries. 2nd edition. 

Greenwood, D. C., Muir, K. R., Packham, C. J., & Madeley, R. J. (1996). Coronary heart disease: a review of the role of psychosocial stress and social support. Journal of Public Health, 18(2), 221-231. 

Johns Hopkins Medicine Coronary Heart Disease.   

Lopez, E. O., Ballard, B. D., & Jan, A. (2023). Cardiovascular disease. In StatPearls [Internet]. StatPearls Publishing 

Mayo Clinic Coronary artery disease. 

Mensah, G. A., Wei, G. S., Sorlie, P. D., Fine, L. J., Rosenberg, Y., Kaufmann, P. G., ... & Gordon, D. (2017). Decline in cardiovascular mortality: possible causes and implications. Circulation research, 120(2), 366-380. 

Nabel, E. G. (2003). Cardiovascular disease. New England Journal of Medicine, 349(1), 60-72. 

Shahjehan, R. D., Sharma, S., & Bhutta, B. S. (2024). Coronary artery disease. In StatPearls [Internet]. StatPearls Publishing. 

Torpy, J. M., Burke, A. E., & Glass, R. M. (2009). Coronary heart disease risk factors. Jama, 302(21), 2388-2388. 

Van Elderen, T., Maes, S., & Dusseldorp, E. (1999). Coping with coronary heart disease: a longitudinal study. Journal of psychosomatic research, 47(2), 175-183. 

(What is coronary heart disease? Dr Georgios Karagiannis) 

Wise, F. M. (2010). Coronary heart disease: The benefits of exercise. Australian family physician, 39(3), 129-133. 

(world heart foundation federate).