Coronary Artery Spasm

Holding one's chest as an expression of pain is what we always encounter in the media or even in our daily lives in the worst-case scenario. This scene can be repeated nowadays in our surrounding circle, regardless of age, sex, or physical status. This condition gets serious in the WHO's declaration of the death of approximately 18 million people globally from cardiovascular diseases each year.  Moreover, ischemic heart disease, another name of coronary artery disease, was believed to affect 1.72% of the world's population in 2020.¹ We cannot imagine how horrible the experience of coronary artery disease as well as its impacts are without understanding its nature, possible causes and methods of prevention.

About Coronary artery spasm

The coronary arteries are the feeding blood vessels of the heart, so blood flow should be kept patent inside them. The coronary artery spasm is defined as any narrowing in the coronary blood vessels with a subsequent partial or complete obstruction of the blood flow to the heart. 

This results in serious consequences, including the partial or complete death of the contracting muscle of the heart which is known as myocardial infarction. In addition, episodic chest pains, known as angina, can be either too stable to be only triggered by some factors or even unstable to occur atypically without triggering factors. All of these types could end in the death of persons who experience them.²

Pathophysiology

Our blood vessels have a spontaneous mechanism of getting their diameter adjusted to the needs of the organs that they supply. For instance, the coronary blood vessels are expected to contract and get narrower on doing less physical activity than on doing exercise, where the coronaries are expected to be dilated to deliver more blood to the heart.

This mechanism of dilatation can be hindered if the vessel wall is rigid enough. This is  either due to fat deposition in atherosclerosis or due to genetic defects of the blood vessels. This may explain the racial predilection of east Asians to coronary artery disease rather than other populations; this is due to the  genetic deficiency of an oxidizing enzyme that diminishes toxic products of inflammation.³

Moreover, the accumulation of such toxic products may result in worsening the inflammatory status of the blood vessels as well as the heart with a more subsequent serious injury. Additionally, the increase in calcium level of the body is accused of standing beyond the inflexibility of the blood vessels to accommodate the blood needs, including the coronaries.

Symptoms

The coronary artery spasm typically presents with grinding chest pain or chest tightness feeling that radiates to the tip of the left shoulder.  According to their results as well as their duration, they are classified into typical angina which extends less than 20 minutes, or atypical which extends beyond 20 minutes. Their nature of either being relieved by nitrates and exacerbated by exercise or not determines their type. The typical angina is exacerbated by stress and exercise and relieved by nitrates while the atypical is not.⁴

Diagnosis

The diagnosis of coronary artery spasm is not always easily achievable, especially in the absence of triggering factors for its atypical form. The chest pain itself has multiple causes, apart from coronary artery spasms, including gastroesophageal reflux, pneumonia, and even effusion. Yet, some diagnostic aids have contributed to the proper diagnosis in some cases. The electrocardiogram (ECG) is one of these aids that can confirm the diagnosis of coronary artery disease while showing changes in some of its waves (ST segment).⁵ 

The rise in the cardiac enzymes in the blood, such as troponin and CK-MB (creatinine kinase-myoglobin binding, can strongly exclude coronary artery spasm diseases in relation to the time elapsed after the attack due to their high sensitivity.⁶

Diagnostic imaging has contributed to the diagnosis of coronary artery spasm through coronary angiography and cardiac magnetic resonance, which can show the site of blockage of the coronaries as well as the degree of blood flow to the heart. It is worth noting that some pharmacological agents such as sympathetic nervous system stimulators and exercise can provoke the state of the deficit of the coronary blood flow, if existing. This facilitates the picking up of susceptible individuals to coronary artery disease after the attack by simple methods such as an echocardiogram, which is ultrasound imaging of the motility of the heart.⁷

Risk factors

Some people have more predilection to coronary artery spasms after exposure to certain factors. Among these potential factors are emotional and physical stress, heavy drinking and smoking, cocaine, high oestrogen levels, and hyperventilation which precipitates respiratory alkalosis by reducing the carbon dioxide level in the body. You can imagine that low magnesium levels in the body as well as a sedentary lifestyle and obesity can lead to coronary artery spasms in the long run. Even the stoppage of the nitrates, a coronary-spasm therapy, can precipitate a  reflex coronary spasm.⁸

Treatment and prevention

What are the treatments for coronary artery spasms

The main targets of the therapy in case of coronary artery disease are keeping the coronaries patent and dilated as well as avoiding the precipitating factors. According to the most recent updates, the following are required:⁹

• Coronary vessel dilators, either pharmacologically by prescribing nitrates and calcium channel blockers or mechanically using the balloon catheter dilatation. It is worth noting that tolerance to these pharmacological dilators may develop on chronic administration, favoring mechanical intervention.
• Maintenance of the coronary blood flow, using aspirin or thrombolytics in order to prevent further blocking blood clots.
• The fat level reduction by using statins under medical monitoring, otherwise, hepatic troubles may result.
• Stabilization of the heart rate, using pharmacological regulators or even pacemakers.
• Revascularization of the affected parts by the diseased coronaries.

What are the ways to prevent coronary artery spasms

Prevention of coronary artery spasm depends on avoidance of the precipitating factors as well as improving the health status of the coronaries through:

• Exercise would help to keep regular patent blood flow in the coronaries due to less liability to atherosclerosis
• Eating magnesium-rich food can help as well such as Soya beans, peanut butter, cocoa powder, buckwheat and sunflower seeds
• Avoidance of stress in addition to medical follow-up for those who had a history of previous attacks of coronary artery spasm can help

When should I see a doctor

The medical teams are overloaded by accumulated work since the pandemic as well as a long waiting list, so restricting the medical consultation is a must. Nevertheless, one should contact the medical support team or ambulance once there is pain in the chest in the following situations, according to the NHS:

• Chest pain at rest
• Chest pain lasting for more than a few minutes
• Chest pain that seems to be flowing to the rest of the body, especially the left shoulder
• Nausea 
• Sweating
• Dizziness
• History of previous attacks
• History of hypertension and diabetes mellitus with minimal chest pain, as diabetic patients may have less sensation of pain due to their nerve damage

Summary

Coronaries are the top arteries that supply the controlling cardiovascular system of our bodies, despite their small size. Therefore, we have to give attention to any potential cause or affecting disorder of them, mainly the coronary artery spasm. Good control always involves prevention as well as management which includes proper diagnosis and appropriate treatment.