Friday, August 31, 2012

How To Reduce Damage After Heart Attack?

Enlargement of heart, also known as cardiac hypertrophy, will reduce the size of chamber of the heart, including left and right ventricles. It is commonly caused by hypertension (high blood pressure) and heart attack.

In the event of cardiac hypertrophy, cardiac cells will be stretched and release Vascular Endothelial Growth Factor (VEGF), which is a signal protein that helps protect cardiac function and keep cardiac cells alive. It is part of the system that restores the oxygen supply to tissues when blood circulation is inadequate.

Researchers from University of Hawaii at Manoa and University of Hawaii discovered a molecular pathway that might help reduce the damaging effects of cardiac hypertrophy. They have found that stretch of adult cardiac cells promotes release of VEGF through activation of the NFkB signaling pathway. The pathological effects of hypertrophy might be alleviated and the survival chances could be increased for patients who have had a heart attack or suffer hypertension if doctors could target at this molecular pathway.

Funded by the National Center for Research Resources (part of the National Institutes of Health), the study was published on December 13, 2011 in medical journal ‘PLoS ONE’.

As reported by The Burden of Heart Disease in Hawaii, more than 3,100 people in Hawaii die of cardiovascular disease every year, and as many as 70 percent of the adults in Hawaii have at least one risk factor for cardiovascular disease, including diabetes, hypertension and obesity. According to Hawai'i State Department of Health, residents of Hawaii Island, Native Hawaiians, Filipinos, and the poor have higher risks for cardiovascular disease.

Of course, there are many ways that people could lower their risk for heart disease. These include lowering high blood pressure, reducing high bad cholesterol (LDL), staying away from cigarette smoking, engaging in adequate physical activity, managing diabetes, eating healthy diets and maintaining healthy weight.

Friday, August 24, 2012

Why Heart Attack Survivors Should Not Stay Near Major Road?

Heart attack is a common name for myocardial infarction (MI) or acute myocardial infarction (AMI). It occurs as a result of interruption of blood supply to a part of the heart, causing some heart cells to die. In serious cases, victims could end up with death.
Patients who survive heart attack usually have to comply with strict blood pressure management and lifestyle changes including quit smoking, exercise regularly, limit alcohol intake and eat healthy diet. Of course, they will be started on long-term medications as well.
Meanwhile, a recent study pointed out that heart attack survivors should avoid living near major road as this might be hazardous for their health.
Researchers from Beth Israel Deaconess Medical Center in Boston found that heart attack survivors living about 300 feet (100 meters) from a major roadway at the time of their heart attack were 27 percent more likely to die over the next 10 years compared with those who living at least 3,200 feet (1,000 m) away from a roadway. Those who lived between 650 to 3,200 feet (200 to 1,000 m) away from a roadway had a 13 percent higher risk of dying in the next decade.
The findings, which were published in the May 7, 2012’s issue of the journal ‘Circulation’, suggested that exposure to air pollution and traffic noise from the roadway might be the cause.
3,547 people, who were hospitalized for a heart attack at 64 medical centers in the United States between 1989 and 1996, were involved in the study. Their average age was 62.
Over the follow-up period of 10 year, 1,071 participants died: 63 percent of cardiovascular disease, 12 percent of cancer, 4 percent of respiratory failure and 0.4 percent in traffic accidents. Patients living nearer to a major roadway had a higher chance of dying during the follow-up period, even after taking account into several factors that might affect a person’s risk of death including age, smoking status, proximity to a hospital and household income.
According to researchers, their study was limited in that they did not know if participants moved after their heart attack, or if new roadways were built closer to participants' homes. Nevertheless, either of these scenarios could affect the results.
No doubt the study did find a link between proximity to major roads and mortality. But unfortunately, it did not prove that one lead to the other.

Thursday, August 16, 2012

Link Between Second-hand Smoke And Heart Disease

People are already aware that smoking is linked to many medical disorders including heart disease, hypertension (high blood pressure), stroke, lung cancer and COPD (chronic obstructive pulmonary disease).

But how about second-hand smoke that affect non-smokers?

Second-hand smoke is also known as environment tobacco smoke (ETS) and it is a mixture of 2 forms of smoke coming from burning tobacco, namely sidestream smoke (smoke that comes from the end of a lighted cigarette, pipe, or cigar) and mainstream smoke (the smoke that is exhaled by a smoker).

Non-smokers are said to have involuntary smoking or passive smoking when they are exposed to second-hand smoke. The more they are exposed to, the higher the level of those harmful chemicals will be inhaled into the body.

Researchers from the Chinese PLA General Hospital in Beijing found that people regularly exposed to second-hand smoke might raise their risk of dying from various causes including heart disease and lung cancer, comparing to those who lived and worked in a smoke-free environment.

The findings of a long-term study based on 910 adults (439 men and 471 women) who were followed over a period of 17 years were published in the May 2012’s issue of journal ‘Chest’. At the outset, 44.2 percent lived with a smoker, while 52.9 percent inhaled second-hand smoke at work.

249 participants (150 men and 99 women) died over the following years. The risk of death from heart disease, stroke, lung cancer and emphysema were 2 to 3 times higher for people who were exposed to second-hand smoke.

11 percent of the 271 men exposed to second-hand smoke died of stroke, comparing to 6.5 percent of the 168 men who lived and worked in smoke-free surroundings. Though the study could not prove that second-hand smoke was the culprit, they did find evidence of dose-response relationship, which is key to building the case for a cause-and-effect relationship.

The study also revealed that second-hand smoke exposure is highly prevalent in China, the largest producer and consumer of tobacco in the world. In 2010, about one-third of the world’s cigarettes are consumed by China’s 301 million smokers.

Friday, August 10, 2012

Why Heart Disease Patients Should Not Live Alone?

Sick people tend to recover more quickly when their family members accompany them because this would probably make them feel better. Of course, there might not have any scientific report to back this up.

But for people with heart disease, living alone is definitely not good since they would tend to die sooner than those who lived with others. This is what the researchers from Harvard Medical School and other institutions had reported on July 23, 2012 in the ‘Archives Of Internal Medicine’. Previous studies have already associated social isolation with heart attacks and weakened immune systems.

Patients living alone might be more difficult to get their medication refilled and take it regularly. They also do not have anyone at home to call the doctor's office or emergency help should they feel unwell. Furthermore, there are other mechanisms by which living alone could raise cardiac risk. For instance, social isolation and loneliness might play a role and these might be more challenging to fix.

More than 44,000 people from multiple countries, who aged 45 or older and had known heart disease or were at high risk of it, participated in the study. Over a period of 4 years, 7.7 percent of those younger than 65 living on their own died, compared to 5.7 percent of those who did not live alone. The gap was smaller for people who aged between 66 and 80. However, it remained statistically reliable even after accounting for age, sex, employment, ethnicity and country. The living situation of those who aged over 80 was, however, not tied to death rates.

According to researchers, people aged younger than 80 could face psychological and social problems like job strain or loneliness if they lived alone. By comparison, people who were older than 80 and lived alone might be healthier and more independent than those who do not.

Hence, they urged cardiologists to routinely question their patients whether they live alone, and if so, ensure the patients can get their medicine regularly. They also cautioned patients who lived alone not to ignore changes that might be a sign of health problems.

In fact, another paper that was also published in the ‘Archives Of Internal Medicine’ showed that older people who felt lonely had more difficulty performing basic tasks of daily living and died younger than those who did not feel alone.

Thursday, August 02, 2012

When Is Heart Attack Most Harmful?

Heart attack, also known as myocardial infarction (MI), is a condition in which interruption of blood supply to heart occurs and causes heart cells to die. This is commonly due to blockage of a coronary artery.

A study recently reported that the size of a heart attack and the harm it can cause depends on what time it strikes. Researchers from the Minneapolis Heart Institute at Abbott Northwestern Hospital found that the greatest injury that a heart attack causes to the heart is when it takes place between 1am and 5am. This is because key restrictions occur in humans' blood supply according to the time of day, according to their findings published online on November 17, 2011 in the medical journal ‘Circulation Research’.

Studies had found that infarct size after ischemia or reperfusion exhibits a circadian dependence on the time of coronary occlusion in rodents. In order to find out whether a similar circadian dependence of infarct size occurs in humans, researchers analyzed 1,031 patients of acute heart attack referred for primary percutaneous coronary intervention with known ischemic times between 1 and 6 hours.

165 patients, who had their first heart attack because of blocked arteries, were identified. They all had well-defined ischemic times and data on size of heart attack, and area-at-risk were recorded. It was observed that the extent of infarct size was significantly associated with time of day onset of infarction.

The ability of heart to protect itself against more severe damage varies over a 24-hour cycle. It is important for scientists to identify those protective changes since this would help pharmaceutical manufacturers develop medications to prevent cardiovascular disease.

Meanwhile, it is known that sleep consists of different phases. Early morning sleep is known as rapid eye movement sleep during which people dream. While the body is asleep, the mind is still awake. The autonomous nervous system is stimulated and releases hormones like adrenaline, noradrenaline and cortisol. These hormones increase the activity of the heart that beats and works harder but the hormones constrict the blood supply to the heart.

One main reason why heart attack are worst at night is that people tend to wait till morning to go and get examination or treatment from doctors. Most people might just think that it was indigestion and simply took some antacids.