Heart Disease

 Heart Disease

Heart disease describes a range of conditions that affect your heart. Diseases under the heart disease umbrella include blood vessel diseases, such as coronary artery disease; heart rhythm problems (arrhythmias); and heart defects you're born with (congenital heart defects), among others.

The term "heart disease" is often used interchangeably with the term "cardiovascular disease." Cardiovascular disease generally refers to conditions that involve narrowed or blocked blood vessels that can lead to a heart attack, chest pain (angina) or stroke. Other heart conditions, such as those that affect your heart's muscle, valves or rhythm, also are considered forms of heart disease.

Many forms of heart disease can be prevented or treated with healthy lifestyle choices.

Symptoms of heart disease

1. Chest Pain, Pressure, Fullness, or Discomfort. 

2.  Discomfort in other areas of your body. 

3.  Difficulty breathing and dizziness. 

4.  Nausea and cold sweats. 

   
   
   

Causes

Genetics

Genetic factors influence the development of cardiovascular disease in men who are less than 55 years old and in women who are less than 65 years old. Cardiovascular disease in a person's parents increases their risk by 3 fold. Multiple single nucleotide polymorphisms (SNP) have been found to be associated with cardiovascular disease in genetic association studies, but usually, their individual influence is small, and genetic contributions to cardiovascular disease are poorly understood.

Age

Age is the most important risk factor in developing cardiovascular or heart diseases, with approximately a tripling of risk with each decade of life. Coronary fatty streaks can begin to form in adolescence. It is estimated that 82 percent of people who die of coronary heart disease are 65 and older. Simultaneously, the risk of stroke doubles every decade after age 55. 

Aging is also associated with changes in the mechanical and structural properties of the vascular wall, which leads to the loss of arterial elasticity and reduced arterial compliance and may subsequently lead to coronary artery disease. 

Sex

Men are at greater risk of heart disease than premenopausal women. Once past menopause, it has been argued that a woman's risk is similar to a man's although more recent data from the WHO and UN disputes this. If a female has diabetes, she is more likely to develop heart disease than a male with diabetes.

Tobacco

Cigarettes are the major form of smoked tobacco. Risks to health from tobacco use result not only from direct consumption of tobacco, but also from exposure to second-hand smoke. Approximately 10% of cardiovascular disease is attributed to smoking; however, people who quit smoking by age 30 have almost as low a risk of death as never smokers.

Physical inactivity

Insufficient physical activity (defined as less than 5 x 30 minutes of moderate activity per week, or less than 3 x 20 minutes of vigorous activity per week) is currently the fourth leading risk factor for mortality worldwide.

Diet

High dietary intakes of saturated fat, trans-fats and salt, and low intake of fruits, vegetables and fish are linked to cardiovascular risk, although whether all these associations indicate causes is disputed. The World Health Organization attributes approximately 1.7 million deaths worldwide to low fruit and vegetable consumption. Frequent consumption of high-energy foods, such as processed foods that are high in fats and sugars, promotes obesity and may increase cardiovascular risk. The amount of dietary salt consumed may also be an important determinant of blood pressure levels and overall cardiovascular risk. There is moderate quality evidence that reducing saturated fat intake for at least two years reduces the risk of cardiovascular disease. High trans-fat intake has adverse effects on blood lipids and circulating inflammatory markers, and elimination of trans-fat from diets has been widely advocated. In 2018 the World Health Organization estimated that trans fats were the cause of more than half a million deaths per year. There is evidence that higher consumption of sugar is associated with higher blood pressure and unfavourable blood lipids, and sugar intake also increases the risk of diabetes mellitus. High consumption of processed meats is associated with an increased risk of cardiovascular disease, possibly in part due to increased dietary salt intake.

Alcohol

The relationship between alcohol consumption and cardiovascular disease is complex, and may depend on the amount of alcohol consumed. There is a direct relationship between high levels of drinking alcohol and cardiovascular disease. Drinking at low levels without episodes of heavy drinking may be associated with a reduced risk of cardiovascular disease, but there is evidence that associations between moderate alcohol consumption and protection from stroke are non-causal. At the population level, the health risks of drinking alcohol exceed any potential benefits.

Celiac disease

Untreated celiac disease can cause the development of many types of cardiovascular diseases, most of which improve or resolve with a gluten-free diet and intestinal healing. However, delays in recognition and diagnosis of celiac disease can cause irreversible heart damage.

Sleep

Sleep disorders such as sleep disordered breathing and insomnia, as well as particularly short duration of sleep or particularly long duration of sleep, have been found to be associated with a higher cardiometabolic risk.

Air pollution

Particulate matter has been studied for its short- and long-term exposure effects on cardiovascular disease. Currently, airborne particles under 2.5 micrometres in diameter (PM2.5) are the major focus, in which gradients are used to determine CVD risk. Overall, long-term PM exposure increased the rate of atherosclerosis and inflammation. In regards to short-term exposure (2 hours), every 25 μg/m3 of PM2.5 resulted in a 48% increase of CVD mortality risk. In addition, after only 5 days of exposure, a rise in systolic (2.8 mmHg) and diastolic (2.7 mmHg) blood pressure occurred for every 10.5 μg/m3 of PM2.5. Other research has implicated PM2.5 in irregular heart rhythm, reduced heart rate variability (decreased vagal tone), and most notably heart failure. PM2.5 is also linked to carotid artery thickening and increased risk of acute myocardial infarction.

Depression and traumatic stress

There is evidence that mental health problems, in particular depression and traumatic stress, are linked to cardiovascular diseases. Whereas mental health problems are known to be associated with risk factors for cardiovascular diseases such as smoking, poor diet, and a sedentary lifestyle, these factors alone do not explain the increased risk of cardiovascular diseases seen in depression, stress, and anxiety. Moreover, posttraumatic stress disorder is independently associated with increased risk for incident coronary heart disease, even after adjusting for depression and other covariates.

Prevention

Diet

A diet high in fruits and vegetables decreases the risk of cardiovascular disease and death. Evidence suggests that the Mediterranean diet may improve cardiovascular outcomes. There is also evidence that a Mediterranean diet may be more effective than a low-fat diet in bringing about long-term changes to cardiovascular risk factors (e.g., lower cholesterol level and blood pressure). The DASH diet (high in nuts, fish, fruits and vegetables, and low in sweets, red meat and fat) has been shown to reduce blood pressure, lower total and low density lipoprotein cholesterol and improve metabolic syndrome; but the long-term benefits have been questioned. A high fibre diet is associated with lower risks of cardiovascular disease.

Medication

Blood pressure medication reduces cardiovascular disease in people at risk, irrespective of age, the baseline level of cardiovascular risk, or baseline blood pressure. The commonly-used drug regimens have similar efficacy in reducing the risk of all major cardiovascular events, although there may be differences between drugs in their ability to prevent specific outcomes. Larger reductions in blood pressure produce larger reductions in risk, and most people with high blood pressure require more than one drug to achieve adequate reduction in blood pressure. Adherence to medications is often poor and while mobile phone text messaging has been tried to improve adherence, there is insufficient evidence that it alters secondary prevention of cardiovascular disease.

Physical activity

Exercise-based cardiac rehabilitation following a heart attack reduces the risk of death from cardiovascular disease and leads to less hospitalizations. There have been few high quality studies of the benefits of exercise training in people with increased cardiovascular risk but no history of cardiovascular disease.

Dietary supplements

While a healthy diet is beneficial, the effect of antioxidant supplementation (vitamin E, vitamin C, etc.) or vitamins has not been shown to protect against cardiovascular disease and in some cases may possibly result in harm. Mineral supplements have also not been found to be useful. Niacin, a type of vitamin B3, may be an exception with a modest decrease in the risk of cardiovascular events in those at high risk. Magnesium supplementation lowers high blood pressure in a dose dependent manner. Magnesium therapy is recommended for people with ventricular arrhythmia associated with torsades de pointes who present with long QT syndrome as well as for the treatment of people with digoxin intoxication-induced arrhythmias. There is no evidence to support omega-3 fatty acid supplementation.