Lipp Vis Nursing ChaptLWBK1630_C02_p013-068

50  Chapter 2 • Cardiovascular Care

ARRHYTHMIA DISORDERS

ATRIAL FIBRILLATION AF is a rhythm that is characterized by an irregular rhythm resulting in disorganized atria contraction and lack of synchronization between the atria and ventricles. The atria rate may be as fast as 400 beats/min and the ventricular rate will be an irregular 120 to 200 beats/min. AF usually occurs in a patient who has underlying heart disease such

as CAD, rheumatic heart disease, cardiomyopathy, hypertension, HF, and pericarditis. The ineffective atrial contractions and/or rapid ventricular response leads to decreased cardiac output. There is a great potential for clot formation to develop because of the blood stasis that develops in the heart as the chambers do not have enough time to empty completely between each beat. These clots can

travel to the brain leading to a stroke. AF, accounts for 20% of all strokes. On the EKG, there will be no P waves or the P waves are erratic, irregular, baseline fibrillatory waves. The QRS complexes are of uniform configuration and duration. AF is most commonly due to hypertension, HF, and increasing age.

Atrial arrhythmias ● Premature atrial contractions ● Atrial fibrillation ● Atrial flutter Atrioventricular (AV) blocks ● First-degree AV block ● Second-degree AV block ● Third-degree AV block

Sinus node arrhythmias ● Sino-atrial block ● Sinus bradycardia ● Sinus tachycardia

PICTURING PATHO

Junctional arrhythmias ● AV junctional rhythm

In AF, electrical stimulation does not begin at the SA node but instead at other, ectopic areas within the atria or at the pulmonary vein. This causes an irregular rhythm as well as an increase in the heart rate. (Reprinted with permission from Stewart JG. Anatomical Chart Company Atlas of Pathophysiology . Philadelphia: Wolters Kluwer; 2018.)

Ventricular arrhythmias ● Premature ventricular contractions ● Ventricular fibrillation ● Ventricular tachycardia

In AF the heart rhythm is irregular and there is no distinct P wave since the impulses are not arising from the SA node. (Reprinted with permission from Martindale JL, Brown DFM. A Visual Guide to ECG Interpretation . 2nd ed. Philadelphia: Wolters Kluwer; 2016.)