Pathophysiology

Pathophysiology Study Guide

©2018 of 131 respiration, and administration of intravenous drugs. If these techniques do not work, in extreme cases, cardio-version may have to resort. The serious instances of atrial rhythm include atrial fibrillation and atrial flutter. Atrial flutter is characterized by a heart rate of about 150 beats per minute, which can be regulated through drugs, electric shock, and stimulation of a pacemaker of the right atrium. In contrast, atrial fibrillation is a more common complication and is likely to affect adults over 60 years of age. The cause of atrial fibrillation is mitral stenosis. Drugs therapy and cardio-version are effective in controlling the heart rate but the patient remains in the situation of atrial fibrillation. This disorder is not life- threatening but may lead to the development of emboli and strokes. Ventricular Ventricular arrhythmias are much more serious than atrial arrhythmia and can even become fatal. There are different categories of this disorder. The most common type of ventricular arrhythmia is ventricular premature or ectopic beat. When these beats appear more than three times, it is known as ventricular tachycardia. It can further be categorized as sustained and non-sustained. With non- sustained ventricular tachycardia, the normal rhythm is resumed spontaneously, while sustained ventricular tachycardia is not resolved until intervened by treatment. The non-sustained type can lead to ventricular flutter and fibrillation. The evaluation of ventricular arrhythmia should be done using continuous electrocardiogram using a Holster monitor. An electrophysiology study is done in specific cases. Treatment of this disorder includes prophylactic and remedial therapy. Another ventricular conduction disorder is bradycardia. In this case, the ventricles are activated since the atrial impulses are not reached, which contracts the ventricles and impacts the pumping function of the heart. The ventricle pacemaker activates, which works as slow as 30 beats per minute. However, a pacemaker can make the rhythm fall and even interrupt, causing ventricular standstill. When the bradycardia falls below 20 beats per minute, it can lead to unconsciousness. An electronic pacemaker is an important therapeutic tool in treating severe bradycardia. Enhanced Automaticity Automaticity can be defined as the feature of any tissue of the heart that is capable of generating an impulse. The automaticity is said to be enhanced when a faster than normal impulse is generated by tissue other than the sinus node. Premature atrial contractions (PAC) are defined as an early beat generated from an ectopic atrial focus. These waves may be generated even without any precipitating factor like alcohol, pseudoephedrine, etc. The PAC, also known as atrial premature beats, acts as a sign of a cardiopulmonary disorder. These waves are seen on the ECG where the baseline segment is given by P wave followed by T wave, is inverted and reside within the T wave. The interval between the pre- PAC beat and post-PAC beat is less than twice the time taken for two consecutive sinus beats. In the Achieve Page 47