Measuring the heart rate is one of the key diagnostic methods in identifying a cardiac condition. The normal heart rate of an individual is 60 – 100 when the cardiac muscle is in resting condition. Tachycardia is a condition in which the normal heart rate of a person increases and the entire rhythmic contraction of the heart muscle is affected. Sinus Tachycardia is usually a response of the cardiac muscle to exercise, stress or underlying illness. Although there are many forms of tachycardia, it is broadly classified into two predominant types depending upon the chambers of the heart.
The conditions are associated with the atrial chambers or the upper chambers of the heart. They are further classified.
Atrial Fibrillation: In this condition, the cardiac electrical conductivity is rapid and irregular leading to irregular heart muscle contraction. The rapid contractions thus produced affect the ventricles. This type of cardiac disease is associated with hypertension and hyperthyroidism. Another associated condition related to atrial fibrillation is atrial flutter.
Supra Ventricular Tachycardia: This condition is caused above the ventricles causing abnormal cardiac conduction leading to superimposed or overlapped signals. It is related to AV node abnormalities in which the cardiac signal arriving at the AV node is split into two with the rebound of one signal to the atria and one signal to the ventricle. These conditions can also lead to Wolf Parkinson's disease which emphasizes the deflected pathway of the arriving signal.
Ventricular tachycardia is a serious cardiac condition. Ventricular fibrillation and associated tachycardia is because of rapid and uncontrolled emergence of cardiac electrical signals leading to extreme arrhythmia and subsequent heart failure.
Cardiac diseases are predominantly caused because of stress or congenital deformities. In most cases obesity, alcohol, smoking and drug abuse have been the predominant sources of increased mortality because of cardiac attacks.
Diagnosis and Treatment
Cardiac conditions are detected with an ECG. The ECG reveals the cardiac conductivity in the four chambers of the heart. Altered patterns can be observed clearly in comparison with the normal graph generated by one cycle of cardiac conduction. Holter monitor, an advanced and portable device performing similar function is used on patients to monitor their cardiac activity for a period of 24 hours. Treatment methods usually include administration of beta-blockers to control arrhythmia and to prevent the occurrence of stroke. Vagus nerve maneuvers and defibrillation methods often help in the recovery of the heart muscle from rapid arrhythmia.
A holter monitor or ambulatory electrocardiography device is a portable equipment that is used to monitor electrical activity of the heart. There are a series of electrodes attached to the chest of the patient that can record electrical signals from the heart. There is a recording monitor that can be carried in the pocket or worn around the neck. The patient's EKG for 24 hours is recorded. Values such as average heart rate, maximum and minimum heart rate are calculated. ECG tracing using Holter monitor is conducted on patients who suffer prolonged fatigue and episodes of low blood pressure and fainting.
A Holter monitor aids in recording any abnormal activity of the heart. The Holter monitor is worn by the patient as he/she goes about his daily routine. It is possible to observe occasional cardiac arrhythmia, atrial fibrillation and atrial tachycardia with a Holter monitor. This device is also advised for patients who have suffered a heart attack or under cardiac medication. A Holter monitor aids in monitoring the performance of a heart pacemaker. Smoking and close proximity to devices such as magnets and metal detectors and some electrical appliances can affect the Holter monitor readings.
Dyspnea is commonly known as breathing difficulty or shortness of breath. It is noticed as difficulty in breathing or labored breathing. Tachypnea refers to rapid breathing. Progressively it can lead to hyperventilation such as experienced during an anxiety attack. Studies indicate that the origin of dyspnea is initiated with inaccurate central nervous system to the lungs with respect to breathing.
The etiology of dyspnea is related to conditions such as Pulmonary Embolism (PE), asthma, COPD, pulmonary ischemia and pneumonia. The management of dyspnea is only effective when the underlying causes are treated. In case of trauma, pneumothorax is an acute trigger for initiating the onset of dyspnea and hence emergency care is given to prevent internal bleeding that is caused in the pneumothorax. This condition can also progress into tachypnea and varied lung and heart sounds which has to be managed with effective ER procedures.
Positional dyspnea: If a person suffers dyspnea when lying down, it might be suggestive of CHF or pericardial effusion.
Exertional dyspnea: This occurs when there is reduction in oxygen supply and is mostly noticed in patients suffering cardiac disease or anemia.
Transient dyspnea: This situation usually resolves without medical intervention and is triggered by reversible causes such as panic attacks.
Recurrent dyspnea: Here the patient suffers these episodes many times.
Conditions such as pulmonary embolism can also lead to dyspnea along with tachycardia and diminished breathing patterns. Dyspnea is an immediate progressive condition usually associated with previous history of trauma or illness such as Tuberculosis, bronchopneumonia, infectious mononucleosis and sepsis in certain scenarios. Since dyspnea is an associated condition and it is predominantly an upper airway obstruction, the treatment measures are often related to avoiding exposure to chemicals, pollen, toxic fumes and gases such as carbon monoxide. Diagnostic tools such as Pulse Oximetry, blood tests for anemia, ECG and metabolic study are used to aid the diagnosis and then initiate appropriate treatment.
Bibliography / Reference
Collection of Pages - Last revised Date: October 16, 2017