Nurse Teachings on Causes and Risk Factors for Myocardial Infarction

Nurse educated the patient and caregiver on the causes and risk factors for myocardial infarction as follows:

Like every other body organ, even the heart will need oxygen-rich blood to survive. Oxygenated blood is supplied to the heart muscle through arterial system called coronary circulation. Two major coronary arteries branch from the aorta, right and left coronary arteries. Coronary arteries further branch off into smaller arteries to provide oxygenated blood to the entire heart muscle. Severe compromise of the coronary arteries due to various factors discussed below can disrupt blood & oxygen supply to the heart muscle, leading to myocardial infarction, and irreparable damage to the heart muscle.
  1. Atherosclerosis: Cholesterol plaques could get deposited on the inner surface of the coronary arteries in individuals with history of atherosclerosis. This can result in collapse of the lumen of coronary arteries, thus compromising their ability to carry and deliver blood. Severely compromised blood supply to cardiac muscle can lead to myocardial infarction.
  2. Emotional stress: Hormones released during stress, such as, adrenaline and noradrenaline, increase the blood pressure, by causing generalized constriction of blood vessels, including the coronaries. This will compromise blood supply to the cardiac muscle. Also, these hormones increase the workload on the heart, by increasing the heart rate. Increased workload on the heart muscle demands more blood & oxygen supply. But the heart muscle does not have enough blood & oxygen supply to match up with the increased workload, due to collapse of coronary blood vessels. This extreme disproportion between blood & oxygen supply and demand can lead to chest pain and myocardial infarction.
  3. Emboli: Rupture of cholesterol plaques in individuals with atherosclerosis can result in dislodgement of fragments of cholesterol and become free floating in the circulation. Also, individuals with poor ambulation, sedentary lifestyles, and history of arrhythmias can be at increased risk to form blood clots. These blood clots can become freely floating in the circulation. These free-floating particles in the circulation are called emboli. These emboli can obstruct the coronary arteries, cause severe compromise of blood supply to the heart muscle and result in myocardial infarction. Also, inactive lifestyle contributes to obesity, atherosclerosis, increased fat deposition in the coronaries and thereby, increase risk for myocardial infarction.
  4. Cold weather: Cold environmental temperatures can result in generalized constriction or collapse of blood vessels, including coronary blood vessels, in an attempt to conserve body heat. This collapse of coronary arteries can cause severe compromise of blood supply to the heart muscle and result in myocardial infarction.
  5. Cardiac arrhythmias: Individuals with history of cardiac arrhythmias are at increased risk for blood clot formation. These blood clots can become freely floating in the circulation. These free-floating particles in the circulation are called emboli. These emboli can obstruct the coronary arteries, cause severe compromise of blood supply to the heart muscle and result in myocardial infarction.
  6. Coronary artery spasm: Coronary arteries are made up of muscle that can help them to widen or collapse, as needed. This muscle, secondary to various factors, such as, excessive cold or chronic smoking, can undergo spasm and collapse or constrict. This collapse of coronary arteries can cause severe compromise of blood supply to the heart muscle and result in myocardial infarction.
  7. Electrolyte imbalances: Excess or too low of salts, such as, potassium and sodium, can result in altered rhythm of the heart and even complete arrest of heartbeat. Grossly altered rhythm or total absence of heartbeat can severely compromise the pumping action of the heart and thereby, hamper blood & oxygen supply to the heart muscle. Severely compromised blood & oxygen supply to cardiac muscle can lead to myocardial infarction.
  8. Excessive smoking: Nicotine in the cigarettes can cause damage to the inner lining of the blood vessels and consequently, increase the risk for atherosclerosis, deposition of cholesterol plaques, and compromise the coronary arteries. Also, smoking can contribute to spasms and generalized collapse of blood vessels, including coronaries. This compromise of coronary arteries can reduce their ability to carry blood & oxygen to the heart muscle. Severely compromised blood & oxygen supply to cardiac muscle can lead to myocardial infarction.