Cardiac arrest is a medical term that refers to the mechanical cessation of the heart resulting to the absence of circulating blood in the system. The cessation of blood flow to the vital organs of the body results in death if left untreated. Sudden cardiac arrest refers to the abrupt cessation of cardiac function with minimal warning.
Patients having a cardiac arrest will present with abrupt and drastic symptoms before the disease becomes eminent. In a number of cases, patients would suddenly collapse unconscious and may gain consciousness after a few minutes, or may never regain consciousness at all. It is also observable that breathing can arbitrarily stop during the cardiac event. Pulses may become faint or may not be appreciable at all especially during shock. In some cases of cardiac arrest, a number of signs may herald its onset like chest pain, fainting, dizziness, fatigue, shortness of breath, palpitation, vomiting, and weakness.
The following diagnostic modalities and tests are done to patients suspected of having cardiac arrest:
The following treatment modalities are used in patients who present with cardiac arrest:
The prognosis of cardiac arrest greatly depends on several signs during the CPR phase. Patients will have better outlook when they have an unsupported systolic pressure of 90 mmHg after the arrest. For those who became unconscious during the cardiac arrest, a spontaneous vascular circulation within less than 25 minutes offers a good chance of survival after the event. Patients who stay unconscious may have a good outlook if they show signs of neurological responsiveness upon stimulation .
The most common condition that leads to cardiac arrest are cardiac arrhythmias . There are a number of cardiac conditions that may lead to life-threatening cardiac arrhythmias:
In the United States, cardiac arrests account for at least 350,000 deaths per year. The annual prevalence rate translates to 1 to 2 cases per 1000 adult population. More than half of the cases of cardiac arrest have an underlying diagnosed or undiagnosed coronary artery disease. Patient who survives a cardiac arrest event will have a higher chance of recurrence within the first 6 to 24 months from the initial attack. Internationally, mortalities associated with cardiac arrests number up to 7 million deaths per year .
Among the more than 300,000 cardiac arrest deaths in the United States, at least 40% of these occur unwitnessed. Mortality in cardiac arrest greatly depends on the competence of the by-stander to conduct an immediate cardiopulmonary resuscitation (CPR) to the victim, and the duration between the time of arrest and the conduction of the patient to the nearest hospital . Deaths with cardiac arrest are seen to be higher among the black races compared to the white ones . Men are more prone to cardiac arrest than women with prevalence ratio of 3:1. In the Framingham cardiac studies, the highest age incidence where cardiac arrest was observed were between the ages 45 to 54 years old .
The abnormal electrophysiologic mechanisms involved in the development of arrhythmias that lead to cardiac arrest are diverse and multifactorial. Alteration in normal physiology that may affect the normal electroconductivity of the heart impulses emanates from the subcellular, cellular, tissue, and organ level. In the subcellular level, abnormalities in the sodium, potassium, and calcium channels increase the likelihood of ventricular tachyarrhythmias and ventricular fibrillation. A sick sinus at the cardiac tissue level that causes asystole and bradyarrhythmias accounts for 20% to 30% of cardiac arrest deaths. Organic defects with hypertrophic cardiomyopathy and dilated cardiomyopathy are associated with high risk for sudden cardiac arrest.
The best way to prevent the occurrence of a cardiac arrest is to actively reduce its established risk factors. Patients with diagnosed cardiac diseases must abide religiously with their maintenance medications and visit their cardiologist regularly. A smoke free and a stress free lifestyle will prevent a number of cardiac events and would significantly lower the strain to the heart. A nutritious diet that is good for the heart should also be in place. An active lifestyle with regular cardio exercises will lower the likelihood of a sudden cardiac arrest.
Cardiac arrest is described to be the sudden and unexpected loss of cardiac function, consciousness, and breathing. Cardiac arrest usually ensues with an inciting electrical disturbance to the heart resulting in pump failure and the discontinuation of the blood flow in circulation. Cardiac arrest is considered a medical emergency, any delay in resuscitative efforts can result to sudden cardiac death and eventually the patient’s demise.
Cardiac arrest is a medical term that refers to the mechanical cessation of the heart resulting to the absence of circulating blood in the system resulting to a serious physiologic disturbance.
The great majority of cardiac arrest is caused by cardiac arrhythmias. There are a number of cardiac disorders that predisposes to arrhythmias like coronary artery disease, myocardial infarction, cardiomyopathy, and congenital heart diseases.
ECG is imperative in the face of a cardiac arrest. Ancillary tests like cardiac enzymes, electrolytes, echocardiography, chest X-ray, and coronary angiogram are also done when the patient is stabilized.
Treatment and follow-upPatients who presents with cardiac arrest must be subjected to immediate cardiopulmonary resuscitation (CPR). Patients may also be given anti-arrhythmics and defibrillation while in the emergency room. Cardiac surgery may be done to repair clogged vessels or correct congenital cardiac defects that can cause arrhythmias.