The Heart: An Incredible Electric Machine

A quick primer on the electrical system of the heart followed by two major breakthroughs in pacemaker technology this year.

What makes the heart beat? Learn about the conduction system, an incredible machine.

A leadless, subcutaneous defibrillator makes the list of 5 biggest medical breakthroughs of the year.

Boston Scientific has begun marketing a FIRST-OF-ITS-KIND DEFIBRILLATOR after receiving FDA approval in September. The implantable device, which protects against sudden cardiac arrest, was developed by a California firm purchased by Boston Scientific and is expected to be a financial win for the Natick-based company. Unlike others on the market, the S-ICD does not touch the heart, instead sending electrical pulses to correct abnormal rhythms through wires implanted just beneath the skin.

http://bostonglobe.com/magazine/2012/10/27/biggest-medical-breakthroughs-year/pLJDenlFAN3XFwwsxfU7CI/story.html

No More Batteries: Piezoelectric Pacemaker Powered By The Heart

An experimental device converts kinetic energy from beating hearts into electricitythan can power a pacemaker, meaning the chance for no more batteries in the future, according to a talk at the American Heart Association’s Scientific Sessions 2012.

The study is preliminary but a piezoelectric approach is promising for pacemakers because they require only small amounts of power to operate. Batteries must be replaced every five to seven years, which is costly and inconvenient.  Piezoelectricity might also power other implantable cardiac devices like defibrillators, which also have minimal energy needs.

“Many of the patients are children who live with pacemakers for many years,” said M. Amin Karami, Ph.D., lead author of the study and research fellow in the Department of Aerospace Engineering at the University of Michigan in Ann Arbor. “You can imagine how many operations they are spared if this new technology is implemented.”

Researchers measured heartbeat-induced vibrations in the chest. Then, they used a “shaker” to reproduce the vibrations in the laboratory and connected it to a prototype cardiac energy harvester they developed. Measurements of the prototype’s performance, based on sets of 100 simulated heartbeats at various heart rates, showed the energy harvester performed as the scientists had predicted — generating more than 10 times the power than modern pacemakers require. The next step will be implanting the energy harvester, which is about half the size of batteries now used in pacemakers, Karami said. Researchers hope to integrate their technology into commercial pacemakers.

Two types of energy harvesters can power a typical pacemaker: linear and nonlinear. Linear harvesters work well only at a specific heart rate, so heart rate changes prevent them from harvesting enough power.

In contrast, a nonlinear harvester, the type used in the study, uses magnets to enhance power production and make the harvester less sensitive to heart rate changes. The nonlinear harvester generated enough power from heartbeats ranging from 20 to 600 beats per minute to continuously power a pacemaker. Devices such as cell phones or microwave ovens would not affect the nonlinear device, Karami said.

http://www.science20.com/news_articles/no_more_batteries_piezoelectric_pacemaker_powered_heart-96003

 

Choices in the care of your heart

Heart disease is challenging and frightful. Sometimes decisions are made very quickly regarding managing the disease process. Heart disease is a chronic condition that rears its ugly head over and over for many. As a heart patient  your best off having a good knowledge of the disease process and the choices of interventions.  Methods of intervention include:

  • Angioplasty (balloon opening of artery)
  • Cutting balloons and roto ruters
  • Stent
  • Drug eluting (coated) stent
  • Open heart surgery – Bypass Surgery
  • Treat medically with medicine and lifestyle
  • Enhanced Eternal Counter pulsation therapy
  • Left Ventricular Assistive Devices
  • Heart Transplant

Many of these decisions are based on the amount of heart tissue that is involved. If there is a large region with insufficient blood flow caused by numerous blocked vessels you most likely will be recommended to have bypass surgery. The general rule is if three vessels are involved you will most likely require surgery. You do have choices though, as the main blockage can be intervened on through stents and the other vessels can be addressed at a later time. We call this staged stents. The  cardiologist do not  recommend placing stents to both the right and the left side of the heart during the same intervention. They will treat the culprit, and then come back later for the others.  The decision tree also takes into account what other issues (co morbidities) a patient has. If  a patient has end stage renal disease or their kidneys were severely affected by the heart problem then the physician my want to avoid treatments that place a heavy burden on the kidneys such as angioplasty or stents. They may opt to treat medically until the kidneys have recovered if they can.

A single vessel blocked will more likely be treated with a stent. However the location of blockage can be very challenging. If the blockage is  where the artery separates to another branch – called an anastamosis  these are very difficult to deal with because a stent would block the flow to the other artery. Sometimes they require surgery, new technology in stents is coming and these may be able to be stented in the future.  Some vessels are too torturous – meaning twisty and turny to allow a stent to be placed. Again surgery, treat medically  or EECP therapy would be considered.

Small vessels are less likely to be treated with stents and more likely to be treated with medications.  Medication includes nitro, long acting nitro, calcium channel blocker, ace inhibitors, beta blockers and occasionally EECP.

Intervention is determined by how viable the heart muscle is. If the heart muscle was severely damaged due to a heart attack  and now scarred over – or remodeled, further intervention to that region is not likely to be of any help.

EECP – it is enhanced external counterpulsation therapy. The therapy consists of cuffs wrapped around legs, calves and buttocks. When the heart finishes pushing the blood flow out, the cuffs sequentially inflate to push the blood back up the heart. By doing this the heart is somewhat engorged with blood and forms collateral vessels. The treatment consists of one hour treatments 5 days a week for 7-9 weeks.  Most patients find their frequency and intensity of angina is greatly diminished. Many patients hold the benefits for 2-5 years, but others will require more frequent return treatments to hold the gains. It is usually covered by insurance such as Medicare if the angina is considered functionally limited or disabling.  For some people with very serious heart damage this improves the pumping ability of the remainder of the heart muscle, as it becomes stronger due to increased blood flow from collateral arteries. The EECP alone will not maintain the benefits, you must still keep physically active through exercise to maintain the benefits.  The treatment is non invasive.

LVAD is a left ventricular assistive device.  These are used when the heart cannot meet the demands any longer to adequately circulate the blood. For many this is now considered a destination therapy. This means they will not be a candidate for a heart transplant but will forever rely on the mechanical pump to circulate their blood. These are becoming more frequently used, and the mortality rates are decreasing with these pumps. If your health care provider is contemplating this route for you, I would strongly suggest you contact support groups of patients who already have LVADS here is a Facebook link to such a support group.  https://www.facebook.com/pages/LVAD-Recipients/207915222572308

Heart transplants are necessary when the damage is such that the heart cannot meet the needs. Often the patient is repeatedly hospitalized in congestive heart failure. They are disabled due to the heart condition.

The take home is know the procedures, research the pro’s and con’s of each. Don’t walk in to the physician’s office and simply take the first suggestion. Question the efficacy, ask the probability of success and what are the limitations, what can you expect in the future. Be active in your healthcare. Most inpatient nurses will tell you they witness too many incidents where the health care provider tells the patient and family if you don’t do this you will die. Thus the patient feels compelled to have the intervention performed. You have choices.

Choices involve the above discussion, but also include risk factor modification every single day. Choose to exercise, choose to eat healthy, choose how to respond to stress, choose to take your medications,  choose to not smoke, choose to monitor blood sugar.

Bypass

Stent

Left Ventricular Assistive Device

 Enhanced External Counterpulsation Therapy

Diabetes blood sugar and A1c elevation tied to heart disease

There  is a strong link  in people with diabetes who also have high cholesterol  Cardiovascular disease  is much more prevalent if their  Hemoglobin A1c is chronically elevated. This significant contribution by elevated HbA1c to increased CVD is independent of statin therapy, and thus requires appropriate HbA1c management in addition to lipids reduction. It is vitally important that any individual with known heart disease and diabetes gets their hemoglobin A1c measured approximately 4 times per year by their primary health care provider. Once a year is not enough. Tight control is imperative. If the blood sugars are constantly running high the vessels that deliver blood to the heart are constantly inflamed setting the stage for further heart issues.

There are many hemoglobin A1c calculators can be found on the internet. here is Medscapes version

http://reference.medscape.com/calculator/hemoglobin-a1c-est-plasma-glucose

Is my heart disease cured?

Many patients come through their heart procedures and feel they are cured. Unfortunately for most, heart disease is a chronic progressive disorder of the arteries in which deposits of cholesterol, calcium, and abnormal cells (that is, plaques) build up on the inner lining of the arteries.  Heart disease usually progressively deteriorates over time, whether due to normal bodily wear or lifestyle choices such as exercise or eating habits. This is a hard concept to grasp, and it doesn’t mean it is a death sentence either.

You can do everything right and still have further heart issues.

When patients struggle with this, I point out doing everything right may be why they survived, as approximately 50% of people do not survive their first heart attack.    It is so important for each person to know their body’s signs and symptoms and not ignore them. We don’t really know what makes coronary artery disease aggressive, there seems to be several factors. These factors include inflammation, c- reactive proteins, genetics, lifestyle to name a few. Some patients will have multiple issues for years requiring frequent interventions and then be fine for many years before having another issue. On average coronary artery bypass  grafts  10 years out will be 50% blocked. Some patients will go 20-30 years before needing another intervention, yet others may not even go a week or month before having symptoms. Thirty percent of open heart surgery patients will continue to have angina symptoms after surgery. The drug eluding stents have  much lower rates of re-stenosis than the bare metal stents which average 25-30% restenosis rates, but in both cases the vessels often continue to develop blockages in other locations in the artery. If the bare metal stents are going to re-stenos the usually do so in the first 3-6 months.  It is vital to stay on the platelet inhibitors – Plavix (clopidogrel) as prescribed to prevent complications.

Photo: According to a recent study based on government nutritional data, we're coming up short in terms of eating a variety of fruit and vegetable colors. For instance, 78 percent don't get enough red. How to work in all those colorful vegetables: http://ow.ly/bxoS1

Accepting the fact that you will have further heart disease is important.

Be on the lookout for new symptoms, for changes in energy patterns, note if you are becoming less active due to fatigue. Keep your risk factors in the best control possible. Try to get blood pressure, blood sugar, cholesterol numbers to national guidelines. Exercise regularly. Eat a rainbow of color in fresh fruits and vegetables each day. Don’t let stress effect your health, manage your stress as best as possible, consider counseling.  Don’t live in fear, live life to its fullest!!

Play hard.         Enjoy your families.

 Embrace life.          Do something rewarding every day.

Laugh.     Mentor others.   Love

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Hot tub and Sauna Safety for Heart Conditions

This is a common question asked by people who have recently undergone a heart issue. It was always a tough one, as some people can and some people shouldn’t. There are a number of concerns for heart patients including elevated heart rates, dehydration, electrolyte depletion, blood pressure issues to be aware of. I have provided you with some education of the benefits and risk. If in doubt of course ask your health care practitioner.

 Vasodilatation -

Benefits: Both steam rooms and dry saunas cause the blood vessels in the skin to dilate, in part accounting for the warm glow appearance afterwards. The blood flow out of the heart increases by 2 or more times after a 10 to 15 minute steam room or sauna exposure.

Risks: However, the blood flow to the internal organs actually decreases, because so much blood is being directed to the skin instead. This can be a problem for those with coronary heart disease. If the heart has to decide where to pump the blood it sends it to the skin to cool the body, and for those with severe blockages the heart then cannot feed itself it’s own oxygenated blood, and then can give symptoms of angina.

People with hard-to-control hypertension (high blood pressure) may experience worsening blood pressure in response to heat exposure. In addition, many blood pressure medications interfere with the normal response of the body to heat exposure.

 Analgesia –
Benefits: Heat has long been recognized as beneficial for folks with fibromyalgia, arthritis and other painful conditions.

Risks: If heat exposure is extreme, excessively prolonged, or if the individual has underlying irritation of the skin, heat can cause the equivalent of a sunburn, or thermal burn. In addition, steam exposure may be a concern if you have had recent surgery (particularly if sutures are still in place) or if you have an open or infected wound. Do not go in a steam room or sauna if you have open wounds.

Diaphoresis (sweating)
Benefits:  The average person will sweat about a pint during a 15 minute session in a sauna, depending on the person’s acclimatization to heat exposure. This has theoretical benefits for cleansing skin pores and some people believe sweating helps clear toxins from the body. This is not well proven and in many instances, is simply not true. In general, people with documented toxicant accumulation in their bodies benefit from specific medical treatment directed at the specific toxicants, rather than sweating. In addition, many of the toxicants of concern these days, for example: pesticides and many metals, asbestos, are not cleared very well through the sweat.

Risks:  The effect of both wet and dry heat to increase fluid loss from the body can also be a problem, particularly if you are already somewhat dehydrated (e.g. after heavy exercise with inadequate fluid replacement or in response to the diuretic effects of caffeine, beverage alcohol, and medications (diuretics). Too much fluid loss can lead to electrolyte imbalance, heart arrhythmias, blood pressure changes, heart rate range changes, light headedness, and fainting.

Dehydration can be a problem in people who have blood vessel blockages to the brain and the heart  The body lacks enough water to fill he blood vessels. Low fluid volume means lower blood pressure. A dehydrated person feels weak and dizzy especially when standing.

Some individuals experience an increase in their migraine headaches in response to dehydration.
There are a number of other medications that can affect the body’s normal response to heat either by inhibiting sweating or by otherwise interfering with the normal physiology, for example, some medications used for psychiatric conditions like schizophrenia. Use of stimulant medications for conditions like ADD or excessive sleeping also increases the health risks from heat exposure.

Dehydration also is dangerous on the kidneys, they will decrease the output of urine and low blood pressure with dehydration can damage the kidneys.

 Calorie Burn:
Benefits: Although exposure to heat increases energy consumption and thereby increases calorie burn, for example, up to 300 to 400 Kcal during a 20 to 30 minute sauna bath, thus helping to promote weight loss, there are clearly more healthful alternatives available, i.e. EXERCISE .

Risks:  Individuals who have been cautioned to restrict exercise intensity by health care providers should be aware that the effects of heat are similar to those of exercise for increasing heart rate. Increasing energy consumption through increased work of the heart can be a concern for people with coronary heart disease, congestive heart failure, valvular heart disease or heart rhythm problems (arrhythmias).

Recommendations:

1- Avoid beverage alcohol and excessive caffeine intake and medications that may impair sweating or increase the health risks from heat exposure.

2- Stay in no more than 15 to 20 minutes at a time.

3- Cool down gradually after use. Avoid going rapidly from a hot to a cold environment, e.g. sauna cold shower as this increases the physiologic stress on the body considerably.

4- Drink 2 to 4 glasses of cool water after each session.


5- Don’t take a sauna or steam bath if you are ill, and if you find yourself feeling unwell while in a steam room or sauna, head for the door.

6- Ask your health care provider for advice and recommendations, if you have any concerns about potential health risks from steam room or sauna use.

HEALTH BENEFITS AND RISKS ASSOCIATED WITH USE OF
STEAM ROOMS AND SAUNAS, Doug Linz MD, Medical Director, TriHealth
Pavilion http://tinyurl.com/7bhlj5u

 If you take a blood thinner (such as Plavix) or blood pressure meds, the heat of a hot tub can combine with the medications to cause you to become dizzy, nauseated or even faint.

When you go in a hot tub, the heated water causes your blood vessels to dilate. In turn, blood pressure drops. If it falls too low, you can pass out.

It may be okay for short periods.

If you are able to carry out moderate exercise without symptoms such as chest pain or shortness of breath, you should be able to tolerate a sauna or soak in the hot tub.

When you get into cold water blood vessels constrict. Any sudden change in temperature leads to a considerable increase in the heart’s workload so moving back and forth between cold water baths and saunas or hot tubs is not a good idea.

Check with your doctor or health clinic to be on the safe side.

http://www.smart-heart-living.com/heart-disease-questions.html#hottub

Yoga for Heart Patients

Yoga is a form of exercise that allows you to build strength, flexibility and develop specific breathing patterns that are beneficial with activity. For heart patients it is essential that you start lightbreath easy and only take the pose to where you are comfortable. Avoid straining the muscles. If you had open heart surgery with a standard sternal incision you will want to wait 10-12 weeks until you sternum is well knit together. Avoid any postures that cause a click or shift in the sternum. 

 

Yoga poses for heart health

There are several poses that you can use in order to increase the health of your heart, and these poses are designed to help your blood to circulate properly and strengthen the heart muscle. The warrior pose and the triangle pose are designed to promote cardiovascular exercise, and prompt you to breathe strategically and adequately. This helps you to increase your stamina, which gives you more energy to complete your daily activities and allow your heart to pump blood through the body quicker. This will help the body to replenish itself quicker, and can even help you to sleep better. The tree pose, the mountain pose, and the lotus pose not only work to strengthen the heart, but can be used to increase flexibility, which can prevent muscle cramping in the future. 

In addition to poses like the mountain pose and the tree pose to help manage and prevent heart disease, doctors have also recommended a healthy diet. Yoga can relieve stress and promote flexibility. The actual improvement of the heart has been proven by many doctors, like Satish Sivasankaran. They have done a study of the benefits of yoga on the heart, and have found that many individuals who practice yoga on a regular basis have had regulated heart beat and circulation. Individuals who may have suffered heart attacks and strokes were able to recover faster by participating in yoga.

 
 

 

 

How Does Yoga Help In Combating This Disease?

A study, published in Journal of The Association of Physicians of India (JAPI), establishes the reversibility of heart disease through yoga. Study was on angiographic ally proven CAD patients, of whom 71 formed the study group and 42 the control group. And the results proved that the serum total cholesterol levels had reduced by 23.3%, disease had regressed in 43.7% and progression was arrested in another 46.5% of the patients. Some marked improvements were noticed in anxiety levels of patients. Controlled yoga combining calming and stimulating measures resulted in reduced serum cholesterol, LDL and triglyceride levels.