The QRS complexes as are usually normal with each following a P wave. First-degree AV block usually requires no treatment. It does require close observation since it can progress to a more serious type of AV block. With a type I second-degree AV block or Wenckebach , the electrical impulses are progressively delayed through the atrial ventricular node until conduction is completely blocked. The heart rate may be normal are slow.
Ventricular rate is greater than the atrial right.
The atrial rhythm is usually regular while the ventricular rhythm is irregular. The P waves are identical with each proceeding a QRS complex except when the P wave is not conducted. There will be a progressive lengthening of the PR interval followed by a P wave that is not associated with a QRS complex. There is a progressively lengthening PR interval until the QRS complexes dropped. With type II second-degree AV block , the electrical impulses are blocked below the level of the AV node.