Degree Options and Education. Students interested in a career in speech therapy should earn a speech therapist degree, bachelorâs degree in communication sciences and disorders or a related major. You will need at least a bachelorâs degree plus your teaching certificate in order to practice speech therapy within the school system.
I think hypokalemia is incorrectly listed as one of the causes of first degree AV block. My ECG handbook says it is hyperkalemia that can cause first degree AV block (and some internet sources confirm this).
The PR interval will vary in second-degree AV block type I (Wenkebach). Note that the PR interval can be altered by changing sympathetic and parasympathetic tone. Because of this, medications such as beta-blockers can lengthen the PR interval and result in a first-degree AV block.