Five out of 10 Filipinos die of heart diseases. Unknown to many, there are several types of heart diseases, these include coronary heart disease, stroke, cardiomyopathy, acute rheumatic fever, peripheral vascular disease, congenital heart disease, and heart failure, which are becoming prevalent and more alarming as recent studies show.
Shortness of breath (dyspnea) when you exert yourself or when you lie down; fatigue and weakness; swelling (edema) in your legs, ankles and feet; rapid or irregular heartbeat; reduced ability to exercise, persistent cough or wheezing with white or pink blood-tinged phlegm; increased need to urinate at night; swelling of your abdomen (ascites); sudden weight gain from fluid retention, lack of appetite and nausea, difficulty concentrating or decreased alertness, sudden, severe shortness of breath and coughing up pink, foamy mucus and chest pains are clear signs that you have a heart failure.
And if you have experienced some of these symptoms, you have all the reason not to shrug them off as recent data from the National Statistics Office (NSO) showed that five out of 10 deaths in the country were of cardiovascular causes.
The Statistics Office also reported that 100,908 people died of heart diseases in 2009. This accounted for 21 percent of all deaths in the country. The World Health Organization (WHO) has said that an estimated 17 million people die of cardiovascular diseases every year. Most of these were heart attacks and strokes, and latetly Heart Failure has been contributiong greatly to the numbers.
In United States alone, About 6 million people have heart failure, according to the Centers for Disease Control and Prevention, and is the primary cause of 55,000 deaths a year.
In the past 20 years, medical care for heart failure has changed radically, with new medications and devices. “Heart failure (HF) is a complication of any heart disease that causes weakening of the heart muscles making the heart unable to perform adequately its function to pump the blood into circulation. It may be caused by sustained elevation of the blood pressure, blockage of the heart arteries, destruction of the heart valves, weakening of the muscles due to various causes, post-partum cardiomyopathy, viral cardiomyopathy, and inborn cardiac anomalies,” continues Dr. Dante Morales, Manila Doctors Hospital senior vice president for medical affairs
Heart failure has many causes, including heart attack, diabetes, high blood pressure and viral infections. But the effect is the same: a heart that doesn’t move blood effectively.With the global trend indicating aging of the various populations including the Philippines, the prevalence of heart failure (HF) is expected to rise.
According to Prof. Alan Maisel, MD, Professor of Medicine at the University of California, and the director of the Coronary Care Unit and Heart Failure Program of the San Diego Veterans Hospital in California, HF is considered a major clinical and public health challenge, wrongly diagnosed in many instances.
In the Philippines, there are no available statistics on HF, and an ongoing study currently being done by the Philippine Heart Association (PHA) as part of the National Nutrition and Health Survey (NNHeS) is expected to give a better picture of the burden of HF in the country.
“HF is considered a major clinical and public health challenge wrongly diagnosed in many instances. ST2 measurement can improve patient care. It can be useful in the assessment of patients with difficulty of breathing or in those with heart attack, Maisel exclaims.”
However, considering that cardiovascular disease remains the leading cause of deaths in the Philippines accounting for almost one third (31.8 percent) of all deaths, it is projected that the prevalence of HF is also high with an estimated 1.8 million of the population suffering from it.
Unfortunately, many cases of HF remain undiagnosed, delaying appropriate treatment. Early identification of patients at risk for HF, especially those who may still have no symptoms but with structural heart diseases that predispose them to HF is critical in order to significantly reduce the rehospitalization and death toll and consequent economic burden of HF in the country and worldwide.
Sounding HF alarm
Maisel, in a small gathering with practitioners and members of the media sounded the alarm for a more aggressive and reliable approach in the early diagnosis of HF, considering that deaths due to it exceed the combined death rate for lung, breast, prostate, and pancreatic cancer, and HIV.
It is also the leading cause for hospitalization in the US, with a poor outcome after hospitalization, explained Prof. Maisel. Studies show a 90-day risk of death of 15 percent and a 30-percent likelihood of being readmitted to the hospital.
One of the breakthroughs in the diagnosis of HF is the discovery of heart biomarkers such as the ST2 cardiac biomarker. The ST2 is a novel indicator of heart stress due to worsening HF. It is a form of body protein, which is a member of the interleukin family; and there is now mounting scientific evidence published in peer-reviewed international journals that it can predict those who may be at risk to die due to HF.
In these studies, patients with ST2 levels above a clinical threshold (cutoff value of 35 ng/mL) consistently have a much higher risk of dying; while those with ST2 levels below the identified threshold have a very low risk of death. The ST2 level also correlates well with HF severity. However, the ST2 level does not distinguish patients with and without HF for diagnosis of HF.
Clinical usefulness
According to Maisel, ST2 measurement can improve patient care. It can be useful in the assessment of patients presenting with difficulty of breathing or in those with a heart attack.
It has been shown to have considerable prognostic or predictive value, specifically in risk-stratifying suspected HF patients to identify those who are at high risk of dying and being rehospitalized for HF.
“With an earlier and more accurate assessment, HF patients can be more aggressively treated with medicines that can effectively improve the heart function and prevent complications including worsening of HF and death. Subsequent rehospitalization could also be reduced with a more accurate guide at monitoring the effectiveness of treatment,” the professor explains.
Repeated or serial determination of ST2 level may be more useful to arrive at a more definitive assessment. The test is not unfavorably influenced by age of patient, impaired kidney function or increased body mass index (in overweight or obese individuals), all of which are limiting factors for other diagnostic biomarker tests for HF.