Sudden Cardiac Death (SCD) : Most are Asymptomatic and When It Happens, Death Ensues

29 September 2023

 

One of the main causes of sudden cardiac death is hypertrophic cardiomyopathy, but most patients don't realise they have it because most don't show symptoms, when the first symptom appears, sudden death ensues as it's too late.

 

Sudden Cardiac Death (SCD) is a sudden, unexpected death due to loss of heart function or cardiac arrest.

Sudden cardiac death can occur at any age from infancy to adulthood. In infants, the condition is called sudden infant death syndrome (SIDS). In adults, it is called sudden adult death syndrome, sometimes also called sudden arrhythmic death syndrome.

Sudden Death in 80% of Adults Due To Coronary Heart Disease

Up to 80% of sudden cardiac deaths in adults are due to coronary artery disease (CAD, or coronary heart disease), which is arguably the leading cause of sudden cardiac death in most adults. Sudden cardiac deaths of those aged 35 years and older, the cause is usually related to coronary artery disease. In contrast, the most common cause of sudden cardiac death in those under-35 age group is fatal arrhythmia, which usually occurs in the presence of a structurally normal heart.

In patients from birth to 13 years of age, the primary cause is congenital anomalies. In patients aged 14 to 24 years, the causes of sudden cardiac death are hypertrophic cardiomyopathy (HCM), arrhythmogenic right ventricular cardiomyopathy (ARVC), congenital coronary artery anomalies, hereditary channelopathies, myocarditis, Wolff-Parkinson-White syndrome, and Marfan's syndrome.

It is important to note that about 49% of people who suffer from cardiac arrest (oriented sudden cardiac death) do not have any symptoms prior to the event. Those who are symptomatic may not have taken any action prior to sudden cardiac death.

Fainting, Rapid Heartbeat, Stomach Upset and Vomiting

Other symptoms of sudden cardiac arrest may include fainting (loss of consciousness), rapid heartbeat, chest pain, dizziness, heaviness in the head, shortness of breath, an upset stomach and vomiting. These symptoms may represent potentially dangerous heart rhythm problems that have begun, which is why these are also sudden cardiac death symptoms.

Several population-based studies have shown that the incidence of sudden cardiac death due to coronary heart disease (CHD) has declined by 15 to 19 percent since the early 1980s. However, an increase in the number of cases of congestive heart failure (CHF) may halt this downward trend in the future.

6:00 am to Noon, The "Devil" Hour

The diurnal peak in sudden cardiac death occurs between 6 am and noon, with a smaller peak in the evening. The overall incidence of sudden cardiac death is higher on Mondays.

Working Long Hours Increases The Risk of Heart Disease

A multivariate cohort study published in the European Journal of Public Health in 2017 showed that people who work long hours have an increased risk of heart disease. The World Health Organisation has also released estimates that about 745,000 deaths from heart disease or stroke in 2016 were linked to working long hours.

The results of the study showed that men are at greater risk. Working around 55 hours a week is more likely to lead to heart disease than working 35 to 40 hours a week.

Not Getting Enough Sleep Increases Blood Pressure

Sleep provides the body with time to recover and recharge, and plays a key role in almost every aspect of physical health. For the cardiovascular system, lack of sleep or sleep deprivation can lead to blood pressure problems and an increased risk of heart disease, sudden heart attack, diabetes and stroke.

7 Suggestions to Prevent Sudden Death

The following recommendations should be implemented in order to prevent sudden cardiac death in both at-risk and non-at-risk patients:

• Stop smoking
• Screen for family history of sudden cardiac death
• Screen for asymptomatic left ventricular dysfunction in patients with a significant family history of cardiomyopathy and sudden cardiac death ．
• Refer family members of patients hospitalised for known cardiac conditions that increases the risk of sudden cardiac arrest for education in CPR and automated external defibrillator use.
• Follow guideline-prescribed medications and use implantable cardioverter-defibrillators in patients with heart failure and reduced cardiac function in which the heart is unable to pump adequately, and who are expected to survive longer than 1 year.
• Use of guideline-directed drug therapy to prevent sudden cardiac death in patients with heart attack and reduced ejection fraction
• Provide screening and necessary counselling for first-degree relatives of survivors of sudden cardiac arrest associated with inherited disorders and counselling on implantable cardioverter-defibrillator (ICD) use for eligible patients.

Article by: Dato' Dr Yap Yee Guan, Consultant Cardiologist, Sunway Medical Centre, Sunway City

Source: Sin Chew Daily

   Back