Heart Attack: Minimising The Risks
Cardiovascular disease was estimated to result in 17.3 million deaths worldwide on an annual basis. Seventy percent of sudden cardiac arrests have been attributed to coronary heart disease. 2016 statistic showed that 16 peoples die from cardiovascular disease (heart diseases and stroke) in Singapore every day. Cardiovascular disease accounted for 29.5% of all deaths. This means that nearly 1 out of 3 deaths in Singapore is due to heart diseases or stroke.
How do we prevent the heart attack?
Can we minimize the risk of heart attack before it is too late?
My suggestions are as follows:
1) Let’s be familiar with the telltale signs of heart attack or coronary heart disease.
The symptoms of heart attack or coronary heart disease include chest pain and it is commonly associated with shortness of breath. Other associated symptoms include dizziness, palpitation (a noticeably rapid, strong, or irregular heartbeat), diaphoresis (unusually heavy sweating), nausea, fatigue, reduced effort tolerance, leg swelling, fainting, intermittent claudication (cramping pain in the legs and especially the calves on walking or exercising that disappears after rest) or even epigastric (upper abdomen) discomfort. A person who has coronary artery disease may also be asymptomatic.
2) Know about your health status by early detection of coronary heart disease and proper evaluation of your heart.
What test do we do to detect coronary heart disease?
CT Coronary Angiography is highly recommended as it is very accurate in providing the anatomical information about your coronary arteries. It detects the abnormal narrowing (stenosis) of the coronary arteries ranges from no narrowing (0%), minimal narrowing (<25%), mild narrowing (25-49%), moderate narrowing (50-69%), severe narrowing (70%-99%) to complete occlusion (100%). It also helps to characterize the types of plaques that a person has in the coronary arteries. i.e., calcified plaque, soft plaque or mixed plaque. In addition, it also provides the important information about the origin and pathway of the coronary arteries. Some people were born with abnormal origin of the coronary artery and the coronary artery runs in abnormal pathway which is at risk of being compressed in between the ascending aorta and main pulmonary artery. This may result in myocardial ischemia (a condition where the heart muscle is starved of oxygen due to inadequate blood supply) and sudden death.
Magnetic Resonance Myocardial Perfusion Imaging (Stress CMR) is frequently used to assess for the presence of myocardial ischemia and myocardial infarction (heart muscle damage due to heart attack) as a result of coronary heart disease. Cardiovascular magnetic resonance is also the gold standard for the assessment myocardial viability.
Other useful assessments include ECG, treadmill exercise test, radionuclide myocardial perfusion imaging, stress echocardiography and cardiac enzymes. Invasive coronary angiography with the aim of percutaneous coronary intervention can also be carried out if patient has clear clinical evidence of significant coronary heart disease with presence of cardiovascular risk factors.
3) Eliminate the cardiovascular risk factors
What are the risk factors for Coronary Heart Disease and Sudden Cardiac Arrest?
1. Hypertension (high blood pressure)
People with baseline hypertension had a 63.3 % lifetime risk of developing cardiovascular disease at 30 years of age compared with a 46.1 % risk for those with normal baseline blood pressure. According to the data from Ministry of Health Singapore, the prevalence of hypertension among Singapore residents aged 18-69 years is around 25%. Recent study performed in China with total participants of 1.7 million showed that the prevalence of hypertension increases gradually as the age of people increases. The prevalence of hypertension for both genders is more than 50% among the participants with age group of 60-64 and it further increases to more than 60% among the participants with age group of 70-74. Essentially this means that at least 1 out of 2 people will have hypertension when they reach the age of 60 and above.
To reduce the risk of developing hypertension, healthy lifestyle is vital. The following measures will help to reduce the risk of hypertension:
-Lose weight in people who is overweight or obese.
-Avoid high salt diet.
-Avoid excessive alcohol consumption.
-Avoid exposure to chronic stress.
Dyslipidemia is defined as elevated total cholesterol (TC), bad cholesterol (LDL-C), triglycerides (TG), non-high-density lipoprotein cholesterol (non-HDL-C) and low level of good cholesterol (HDL-C). The prevalence of dyslipidemia is increased in patients with premature coronary heart disease, being as high as 75 to 85 percent compared with approximately 40 to 48 percent in age-matched controls without coronary heart disease. Therefore, please cut down the fatty food intake.
3. Diabetes Mellitus
Diabetes mellitus is associated with an approximately twofold increased risk of coronary heart disease, stroke and cardiovascular disease mortality. It accounted for 10% of the population-attributable risk of a first myocardial infarction (heart attack). To reduce the risk of getting diabetes mellitus, do not eat more than what is required by the body, avoid overweight or obesity.
4. Cigarette Smoking
Incidence of a heart attack is increased in women and in men who smoke at least 20 cigarettes per day compared with subjects who never smoked. Hence, smoking cessation is strongly advised for smoker.
5. Lack of Exercise
Men who engaged in moderately vigorous sports activity have been reported to have a 23% lower risk of death than those who were less active. The effects of exercise include elevate good cholesterol level; reduce blood pressure; weight loss and less insulin resistance which means reduce the risk of getting diabetes mellitus.
The National Health Survey 2010 showed that 1 in 9 Singaporeans aged 18 to 69 is obese; a 57% increase from 2004. Weight loss in overweight and obese adults is associated with a reduction in mortality. Based on body fat equivalence, the recommended Body Mass Index, (BMI) cut-off points for public health action in Asians were 23 kg/m2 and 27.5 kg/m2, respectively as seen in the Cardiovascular Disease Risk table below.
You can check your own BMI using this formula: Body weight in kilograms divided by the square of the height in meters (kg/m2)
7. Chronic Kidney Disease (CKD)
Cardiovascular mortality is twice as high in patient with stage 3 CKD (Glomerular Filtration Rate, GFR 30-59ml/min per 1.73 m2) and 3 times as high in patient with stage 4 CKD (GFR 15-29 ml/min per 1.73 m2) compared to people with normal kidney function.
8. Family History of Coronary Heart Disease
First-degree relatives (ie, parents or siblings) prior to age 55 for males or 65 for females denotes a significant family history. In the presence of positive family history, there is 40-60% increase risk of developing coronary heart disease.
Microalbuminuria is defined as persistent albumin excretion in urine between 30 and 300 mg/day. Microalbuminuria has been associated with cardiovascular disease that is additive to conventional risk factors in both nondiabetic and diabetic patients.
10. High sensitivity CRP (hs-CRP)
The baseline level of hs-CRP predicts the long-term risk of a first myocardial infarction, ischemic stroke, hypertension, peripheral vascular disease, sudden cardiac death and all-cause mortality among healthy individuals. Individuals with values <1 mg/L have been considered to be at lowest risk, with low-, average-, and high-risk values defined as <1, 1 to 3, and >3 mg/L. For individuals at intermediate risk for cardiovascular disease where a more definite evaluation of cardiovascular risk might change decision about whether or not to start lipid lowering therapy, screening measurement of hs-CRP is suggested.
11. Lipoprotein (a)
Elevated level of lipoprotein (a) may promote atherosclerosis. Lp (a), is a modest, independent risk factor for atherosclerotic cardiovascular disease events, especially myocardial infarction. Lp (a) excess is commonly detected in patients with premature coronary heart disease. 18.6% of patients with premature coronary heart disease were found to have excess Lp (a).
Screening and treatment for Lp (a) excess levels can be considered for:
-Patients with coronary heart disease and no identifiable dyslipidemia.
-Patients with recurrent cardiovascular disease events despite adequate risk factors
-Patients with a strong family history of coronary heart disease and no dyslipidemia.
-Patients with hypercholesterolemia refractory to low density lipoprotein-cholesterol
(LDL-C) lowering therapies.
4) Treat the problem once identified
Revascularization with percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG) can be performed in patient with severe coronary heart disease. PCI is used primarily to open a blocked coronary artery without the need for open-heart surgery. A deflated balloon is advanced into the obstructed artery, inflated to relieve the narrowing and restore blood flow to heart tissue. Stent can then be deployed to keep the blood vessel open.
Prompt revascularization is crucial for enhanced survival. 2013 American College of Cardiology Foundation/American Heart Association guideline recommends use of primary percutaneous coronary intervention (PPCI) for any patient with an acute ST elevation myocardial infarction (heart attack) by persons skilled in the procedure in a timely manner with first medical contact to PCI time of less than 90 minutes for patients transported to PCI-capable hospital.
If any of the cardiovascular risk factors are identified, please seek medical advice as soon as possible. You may need to be treated with medications. Healthy lifestyles like low cholesterol or low fat diet, regular exercise, smoking cessation and maintaining normal weight; adherence to long-term medications, regular review and follow up with the doctor are all essential in ensuring that the problems are managed properly.
In summary, to minimize the risk of heart attack, let us be familiar with the telltale signs of heart attack or coronary heart disease; know about your health status by early detection of coronary heart disease and proper evaluation of your heart; eliminate the cardiovascular risk factors and treat the problem once identified.
Cardiovascular Disease Risk Table
Coronary angiography and percutaneous coronary intervention in acute myocardial infarction. On the left: Right coronary artery (RCA) was occluded. On the right: RCA was successfully dilated and the blood flow was restored.
CT coronary angiography demonstrates severe coronary artery stenosis due to soft plaque.
Dr Wong Siong Sung
Senior Consultant Cardiologist
Medical Director of Healthy Heart Specialist Centre
Medical Director of Somerset Imaging Centre
MD, FAHA, FRCP (Edinburgh), FASNC, FAMS (Cardiology)
MRCP (UK), MRCPS (Glasgow), DCBCCT (USA), DCBNC (USA)