"Three-hyper" diseases: Hypertension, hyperlipidemia and hyperglycemia, and other underlying diseases;
Smoking: More than 90% of current sudden cardiac deaths are related to smoking;
Poor dietary habits: Alcohol abuse, overeating, excessive intake of high-fat and high-protein foods;
Unhealthy lifestyles: Overwork, staying up late, obesity, little physical exercise, improper exercise, or excessive exercise;
Excessive work and mental stress: The causes often induce or aggravate coronary artery spasms, resulting in myocardial infarction. Research shows that mental stress, severe emotional fluctuations, and physical overexertion are highly possible causes of cardiac diseases.
Cardiac arrest happens when patients suffer sudden loss of consciousness, failure to respond to calls, jaw clenching, and limb convulsions. If not rescued in time, patients will soon suffer SCD, with cardiac arrest, respiratory arrest, aortic pulsation disappearance, mydriasis, and areflexia.
A timely and effective rescue may avoid SCD when cardiac arrest occurs. However, valid cardiopulmonary resuscitation must be performed within 4 minutes of the onset of the arrest, or patients may not survive. Even if their breathing and heartbeat are restored, patients may have irreversible damage to their brains and even become vegetative.
SCD deprived the most lives in human history. Among all deaths caused by cardiac diseases in the United States, sudden deaths account for approximately 63 percent, a number surpassing the sum of that by cerebral stroke, lung cancer, breast cancer, and AIDS. Currently, 300,000 to 400,000 people in the United States die of SCD yearly. In China, SCD kills 544,000 people every year, ranking first globally. Most die suddenly outside the hospital, where the survival rate for cardiac arrest patients is only 2% to 15%. Even though taking the rescues in the hospital into account, China's overall survival rate is still less than 1%.
Patients often have no symptoms when ventricular arrhythmias occur on them. However, if they happen, the patients will suffer fatal arrhythmias soon, without blood pumped from the heart. The patients will then lose consciousness within seconds, resulting in irreversible SCD within minutes.
Life support rescue methods: cardiopulmonary resuscitation, defibrillation, tracheal intubation, antiarrhythmic medications, and medications to increase cardiac output.
Implantable cardioverter defibrillator (ICD)
Sudden cardiac death (SCD) is natural death due to a cardiac cause that occurs within 1 hour of the onset of the symptom. The most common cause of SCD is fatal malignant ventricular arrhythmia, which includes ventricular tachycardia and ventricular fibrillation.
