During the COVID-19 pandemic, some patients would be tested with an oximeter only for it to exceed 99%. However, during a medical examination, they would be found to have a “lack of oxygen in the heart”, or hypoxia. Why is it?
It has to do with the type of hypoxia one suffers from. According to Dr. Chungpin Liu, cardiologist and director of the Yupin Clinic in Taiwan, there are three types of hypoxia.
The first is caused by insufficient inhalation of oxygen. For example, drowning, choking on food, having a COVID-19 infection, or having other lung conditions can cause low blood oxygen levels.
Dr. Liu pointed out that this condition is systemic hypoxia. These patients may detect a reduced oxygen concentration in their blood when tested with an oximeter.
The second type is due to poor blood supply. The reason may be that patients’ blood vessels are naturally prone to spasms, which leads to poor blood circulation. Or, due to bad lifestyle habits, fat and bad cholesterol accumulate on the walls of blood vessels, which become thicker and thicker, making blood vessels narrower and harder. This will eventually lead to atherosclerosis, which prevents blood from flowing smoothly to the tissues.
If the blood supply to tissues and organs is low, local hypoxia will occur. For example, when the heart receives less oxygen, it causes cardiac hypoxia.
Dr. Liu pointed out that most types of hypoxia, including cardiac hypoxia, are local and cannot be detected by an oximeter.
Other cases of local hypoxia due to poor blood supply include limb necrosis caused by an accident, in which a limb is crushed by a heavy object, or when people tie a rubber band around their fingers, which turn black due to reduced blood flow.
The third is the insufficient ability of red blood cells to transport oxygen.
Hemoglobin in red blood cells is responsible for transporting oxygen, and red blood cells are responsible for transporting oxygen throughout the body. If there is a lack of hemoglobin, the ability of red blood cells to carry oxygen will be reduced. Likewise, without enough red blood cells, enough oxygen cannot be transported. Therefore, patients with poor blood cell function and severe anemia are prone to local hypoxia.
Neglecting 3 Symptoms of Hypoxia Can Cause Heart Failure and Myocardial Infarction
Cardiac hypoxia can also be called hypoxic lesions and ischemic heart disease, since its most important factor is the blockage of the coronary arteries of the heart. The occurrence of hypoxia can be chronic or acute.
- Acute cardiac hypoxia
When acute platelet agglutination (platelet clumping) occurs in blood vessels, resulting in thrombotic blockage (venous or arterial), it causes acute hypoxia. Myocardial infarction belongs to this category, because its onset is rapid and violent, and patients often collapse quickly. Myocardial infarction can occur due to the fragility of the walls of blood vessels. Or, a patient becomes very tired and has not drunk enough water, and suddenly a blood clot develops and a myocardial infarction occurs.
- Chronic cardiac hypoxia
Compared to acute cardiac hypoxia, chronic cardiac hypoxia is more common.
Its cause is mainly poor blood supply, and another cause is related to anemia. According to Dr. Liu, during the process of clinical diagnosis, a doctor will check at the same time whether the patient’s hemoglobin is sufficient.
Symptoms of chronic cardiac hypoxia: chest tightness, chest pain and shortness of breath. If you are prone to these conditions when walking or exercising, you should be extra careful.
Many people suffer from high cholesterol and smoking, which increasingly narrows their blood vessels and causes wheezing and chest pain when walking. Nevertheless, people often see this as a minor issue and ignore it when the symptoms go away. Dr. Liu pointed out that if not treated immediately, after a long time, cardiac hypoxia can lead to increasing weakness during activities, severe arrhythmia, heart failure and myocardial infarction.
Chronic hypoxia can also become acute, triggering myocardial infarction. Therefore, if you are prone to wheezing, chest pain, and other symptoms, it is recommended that you have your heart checked rather than relying on an oximeter to determine your blood oxygen levels or to ignore the symptoms.
More middle-aged and male patients
If we disregard menopause, the majority of cardiac hypoxia patients below the menopausal age group are men. Women before menopause are protected by female hormones and have better cardiovascular health. In most patients, cardiovascular disease begins to develop after menopause. Thus, after menopause, the proportions of men and women with cardiovascular disease become similar.
Cardiac hypoxia is more likely to occur in patients between the ages of 45 and 65, both in men and in women. And this is mainly caused by the narrowing and hardening of blood vessels, which are linked to aging, cholesterol and smoking.
“If a person starts smoking and having a diet high in oil and sugar when he is young, after the accumulation for more than 20 years, he will be prone to cardiac hypoxia, at the age of 40, and fastigium (period when the symptoms of the disease are most pronounced) begins at the age of 45,” said Dr. Liu.
In order to prevent cardiac hypoxia, we must avoid smoking, reduce the consumption of foods high in oil and sugar, exercise more, and avoid overwork.
5 types of food to prevent cardiac hypoxia
There are also foods that are good for our blood vessels and blood cells.
- Foods Containing Soluble Dietary Fiber
Soluble dietary fiber can reduce the absorption of cholesterol from the intestines and excrete bad cholesterol, which helps keep blood vessels clear, so that blood can flow smoothly to tissues, avoiding local hypoxia.
Foods high in soluble dietary fiber: oats, potatoes, pumpkins, yams, okra, mushrooms, seaweed, cauliflower, carrots, melons, apples, pears, bananas, kiwis, citrus fruits.
Fish is a wonderful source of high quality protein and omega-3 polyunsaturated fatty acids, which are beneficial for blood vessels and red blood cells.
Protein helps in the production of red blood cells; and omega-3s have a preventive effect on atherosclerosis, as they help remove fat from blood vessels and stabilize atherosclerotic plaques.
An epidemiology investigation in Greenland have found that the incidence of ischemic heart disease in Greenlanders is very low, and this is linked to a diet rich in omega-3s.
Omega-3 rich fish are salmon, tuna, mackerel, herring, trout and sardines. We should choose wild rather than farmed fish to avoid toxins.
- Allium and cruciferous vegetables
Both of these groups of vegetables contain organosulfur compounds that allow blood to flow smoothly through the arteries and prevent chronic hypoxia.
Studies found that organosulfur compounds reduce cholesterol synthesis in liver cells and inhibit platelet coagulation. If the ability of platelets to clot increases, it tends to cause the blood vessels to narrow.
Organosulfur compounds can also prevent atherosclerosis and reocclusion of treated coronary arteries.
Common allium vegetables: garlic, onions, leeks, green onions and chives.
Cruciferous vegetables: cabbage, cauliflower, broccoli, green cabbage, arugula, cabbage, radish, kale.
- Meat, fish and shellfish
Iron is an essential mineral for the synthesis of hemoglobin. Without enough iron, hemoglobin synthesis will be insufficient and the amount of oxygen carried by red blood cells will be lower.
Meat, fish, and shellfish are ideal iron-rich foods because the rate of absorption and utilization rate of animal iron by the human body is better than that of vegetable iron.
In addition, when consuming foods containing iron, it is important to eat fruits and vegetables rich in vitamin C at the same time to promote iron absorption.
Fruits and vegetables rich in vitamin C: guavas, papayas, grapefruits, strawberries, kiwis, oranges, tomatoes.
Eggs are a very nutritious food that contains the nutrients needed to prevent anemia and produce hemoglobin and red blood cells, including protein, vitamin B6, vitamin B12, folic acid, copper , iron and vitamin D.
Some people worry that eating too many eggs will make their cholesterol levels too high. However, a 2018 exam pointed out that cholesterol in food has little effect on the body, but saturated fatty acids (SFAs) increase the risk of cardiovascular disease. A large egg (50 grams) contains only 1.56 grams of SFA, making it a healthy and affordable food, according to the review.
A balanced diet is a natural way to get the aforementioned nutrients. Dr. Liu told us that his patients had improved cardiac hypoxia after taking medication, developing good eating habits, and exercising properly.