Sunday, May 30, 2010

Why your heart/blood vessels may get sick (risk factors for heart disease and how they lead to illness), and how to prevent this from happening

Risk factors for heart disease can be roughly divided to major, or traditional (for sure associated with development of heart disease), and minor, or untraditional, which have less strong association with heart disease, but noted to contribute to development of heart disease, especially when combined together.

What are the major risk factors that can't be changed?

Heredity (including race) - Children of parents with cardiovascular disease are more likely to develop it themselves. African-Americans have more severe hypertension than whites. Consequently, their risk of heart disease is greater.

Gender - Men have a greater risk of heart attack than premenopausal women, and have attacks earlier in life.

Increasing age - About four out of five people who die of a heart attack are over 65. At older ages, women are twice as likely as men to die within a few weeks of a heart attack.

What risk factors can be changed?

Cigarette/tobacco smoke - Cigarette smoking is the biggest risk factor for sudden cardiac death. Smokers' risk of heart attack is more than twice that of nonsmokers. Giving up smoking is absolutely crucial for preventing early, aggressive heart disease. I will post a section on “Smoking: why it is bad and how to quit.” for details.

High blood cholesterol levels - The risk of coronary artery disease rises as blood cholesterol levels increase. When other risk factors (such as high blood pressure and cigarette smoke) are present, this risk increases even more. Everything here starts with healthy eating. I will post a section on “High cholesterol control and prevention” on detailed discussion of healthy eating.

High blood pressure - High blood pressure increases the heart's workload, causing it to enlarge and weaken over time. The force with which the heart pushes blood through the body is called "blood pressure." If blood vessels are narrowed because of atherosclerosis or other causes, the heart must pump harder than normal to circulate blood resulting in high blood pressure or hypertension. Eventually if hypertension is not well managed, the heart chambers may become enlarged and the heart muscle may thicken. The heart needs more oxygen to function, and its efficiency decreases. After many years of hypertension, heart failure may occur. High blood pressure also increases the risk of stroke, heart attack, kidney failure and congestive heart failure. When someone with high blood pressure is overweight, smokes, has high blood cholesterol levels or diabetes, the risk of heart attack increases several times. For more information about lowering high blood pressure, read a section on High blood pressure control and prevention.
Physical inactivity - Even modest levels of low-intensity physical activity are beneficial if done regularly and long term. Exercise can help control blood cholesterol, diabetes and obesity as well as help to lower blood pressure. For more details read Exercise!

Obesity - People with an excessive amount of body fat are more likely to develop heart disease even if they have no other risk factors. Excess weight increases the strain on the heart; it influences blood pressure and cholesterol, and can lead to diabetes. Healthy eating and exercise are the answers. Read subsequent blog posts on diet, exercise, and diet pills.

Stress - Scientists have noted a relationship between coronary heart disease and chronic stress. Read blog posts on stress role in heart disease and stress reduction strategies.

Substance abuse - People with a history of substance abuse, particularly cocaine and alcohol abuse place themselves at risk for heart disease.

KNOW YOUR HEART. Structure of the heart and blood vessels and how they work.

( Adopted from“Learn about your heart… Made simple” by Nicolas W. Shammas, MS, MD, FACC, FACP)

The heart is a pump that distributes blood to the organs of the body. The heart is made of 4 chambers. The top 2 collecting chambers are called atria; the bottom 2 ejecting chambers are called ventricles.
The right atrium receives blood deficient in oxygen from the body and sends it into the right ventricle. The right ventricle squeezes the blood out to the lungs to pick up fresh oxygen.The oxygenated blood returns from the lungs to the left atrium, which then funnels the blood into the left ventricle. The left ventricle ejects the oxygenated blood into the entire body via the aorta.

What are the major components of the heart?

The heart is made of a contracting muscle that generates the force required to transport blood to all parts of the body. The muscle contracts from the bottom up to eject the blood into the aorta. The aorta branches out into a network of blood vessels that distributes blood to the organs of the body.

In the heart, there are 4 valves that allow the blood to move in 1 direction only. For example, the aortic valve opens when the ventricle contracts and closes immediately when the heart relaxes, preventing the blood from returning back to the left ventricle.

In addition to the muscle and the valves, the heart is made of a complex electrical system that allows the muscle to pump continuously and predictably. Electrical impulses are generated from a site in the right atrium called the sino-atrial node. This serves as the natural pacemaker of the heart, generating electrical impulses at the normal resting rate of 60 to 100 beats per minute. At a rate of 60 beats per minute, the heart contracts approximately 31,536,000 beats per year.

Describe the heart valves and their function

The 4 valves in the heart that allow blood to move only in 1 direction are the aortic, mitral, tricuspid, and pulmonic valves (see Figure 3). The aortic and pulmonic valves, when open, allow the blood to leave the heart and, when closed, prevent the blood from returning to the heart. The mitral and tricuspid valves, when open, allow the blood to move from the atria to the ventricles and, when closed, prevent the blood from moving backward into the atria.

What is the aorta?

The aorta is the major blood vessel that comes out of the heart and distributes oxygenated blood to the rest of the body including the heart itself . Blood vessels coming out of the aorta and supplying blood to the heart are called coronary arteries.The aorta supplies blood to the head via the carotid and vertebral arteries. Major branches coming out of the aorta also include the renal arteries (supplying blood to the kidneys), the mesenteric arteries (supplying blood to the gut), the celiac artery (supplying blood to the liver and spleen), and the iliac arteries (supplying blood to the hip and lower legs).

What are the blood vessels?

Blood vessels are essentially hollow tubes that carry blood to the organs and tissues throughout your body. The four basic types of blood vessels are:

 Arteries. These blood vessels carry blood away from your heart and out to your body, delivering oxygen and nutrients. The aorta is the largest blood vessel of all.

 Veins. These blood vessels carry deoxygenated blood back to your heart. Lacking oxygen, they have a bluish cast on your skin.

 Capillaries. These tiny vessels connect arteries and veins.

 Lymphatics. Fluid leaks out of capillaries to bathe cells. Lymphatics are delicate vessels that carry this fluid back into your body's central circulation.

What topics I am going to cover in this blog.

(Know truth and myths about your heart, cardiovascular tests, and treatment options)

I. Introduction. Are you sure you and your cardiologist speak the same language? Don’t be so sure.

II. Know your heart

i. Structure of the heart and blood vessels and how they work.

ii. Why your heart/blood vessels may get sick (risk factors for heart disease and how they lead to illness).

iii. Most common diseases of the heart and blood vessels.

iv. Symptoms of most common cardiovascular diseases (know what to look for).

III. What is Framingham score and how to interpret it?

IV. When do you need to see a cardiologist?

V. When do you need to go to the emergency room?


VI. What are those tests doctors use to check your heart and blood vessels? Are they using me as a guinea pig? Vs. I really need it!

a. Blood work

i. Cardiac enzymes

ii. Cholesterol profile

iii. C-reactive protein

iv. Homocysteine

v. Thyroid profile

vi. Iron tests

vii. Others

b. Non-invasive diagnostic tests

i. Electrocardiogram (ECG)

ii. Chest X-ray

iii. Echocardiogram (heart ultrasound)

iv. Carotid ultrasound

v. Peripheral arterial ultrasound

vi. Venous studies

vii. Stress test

1. Treadmill

2. Treadmill with nuclear imaging

3. Stress-echocardiogram

4. Dobutamine-stress echocardiogram

5. Chemical stress test

• Calcium score (EBCT)

• 64-slice CT (CT-angiogram)

• Cardiac MRI

c. Invasive diagnostic tests

i. Cardiac catheterization

ii. Peripheral vascular angiogram

iii. Angiogram of aorta and large vessels

iv. Carotid angiogram

v. Right heart catheterization

vi. Transesophgeal echocardiogram (really, not that “invasive”!)

VII. How will they treat you? Know your treatment options! Make an educated choice!

VIII. Informed consent for special treatments and procedures.

IX. How to prevent cardiovascular disease. How to ignore media myths and invest your time and money wisely.

a. Weight.

b. Comparison of common diets.

c. Diet drugs

d. Exercise

e. Vitamins/supplements

f. Diabetes control and prevention.

g. High blood pressure control and prevention

h. High cholesterol control and prevention

i. Family history of heart disease: how to beat the odds?

j. Smoking: why it is bad and how to quit.

k. Stress management.

l. Sex: benefits for your heart.

m. Drugs for erectile dysfunction: is Viagra good for you?

X. Does gender matter? (Are men really different from women?).

XI. Common mistakes and misconceptions to avoid. Is your cardiologist your friend?

Things cardiologists never tell you. Introduction from your concerned cardiologist.

As a practicing cardiologist, I had to answer most unexpected questions every day. I did it meticulously each time, with a great sense of responsibility, and a great patience. I took my time. I wanted a patient to be happy with my explanation, so we are “on the same page”. Guess, what?

Once I had to deliver unpleasant news to a dear patient of mine. The news was: she had many blockages in her coronary arteries and her heart muscle became weak over years. She needed a bypass surgery. After a bypass surgery, which improves blood flow to the heart muscle, there was a chance that her heart muscle function would improve.

As usually, I went on and on about where the blockages were, what were the risks and the benefits of the open heart surgery, and how long was an expected recovery period.

Patient was listening to me attentively, without interruption, and agreed to the surgery at the end. Then I asked her, as I usually do, if she had any questions. I was stunned when she said:

“Doctor, I think I will have surgery done. I will go with your recommendations. I have only one question: are those veins coming to or from the heart?”

“Excuse me? VEINS? We are talking about the ARTERIES, not veins!

“OK, arteries. I mean, are they before or after the heart?”

“Well, let me start all over again. They are nor BEFORE, neither AFTER the heart. They are ON THE HEART and IN THE HEART!!!” (After thirty minutes of explaining of what seemed obvious to me, I realized that my patient had no concept of cardiac anatomy whatsoever!)

If you think, this is an exception, you are very optimistic. Every single day we see patients, who blindly (yes, blindly!) trust what we tell them, and accept most complicated and risky procedures without having a clue why they need it, and what exactly going to happen to them. You may say: “How about informed consent? Aren’t they supposed to sign it before the procedure? You bet. They do sign. You think they understand everything before they sign. They think they understand. They SAY they understand. And still don’t have a clue! Unbelievable, right?

Another fresh example of what patients may ask me was this one: A physically active, vibrant, and happy 89 years old patient of mine was obviously very excited about something wheh he came to see me for a routine follow-up. When I asked him why he looked so happy and upbeat that day, he enthusiastically said: “Doctor, I studied some literature at home. I read this newspaper article about defibrillators, that they prevent a sudden cardiac death. Well, I decided to ask you to give me one, so I can live for another 40-50 years. Do you think my insurance will pay for it”?

Good question, Mister, let me think…. I don’t think so, especially that at the age of 89 your cardiac problems include only high blood pressure and mildly elevated cholesterol, not a cardiac arrest while playing a final NBA game, or a terribly weak heart muscle following 5 heart attacks at the age of 45.

On the one hand, I feel bad for my patients for lack of knowledge in this field. On the other hand, I realize that it’s not their fault. I spent all these years in training and practice, getting the idea, why should they get it in thirty minutes? I feel I have a right and a moral obligation, as a cardiologist, to clarify things for them. This very goal prompted me to start this blog.

The heart is the most important organ in human body (if we don’t count the brain), and also the most vulnerable one. One can not make mistakes here.

This blog is for people like you, who want to know what they are doing. Who want to be in control of their bodies, to make right choices, to give truly INFORMED consents in the future.

Let’s start our journey into “cardiology made simple”, not “cardiology made confusing”. Hopefully, if you let me lead you through this, the years of your unanswered questions and guessing will be a history.

Svetlana Nikitina, MD, PhD
(your concerned cardiologist)