Which of the following abnormality is seen in first-degree hea block?: (A) PR interval >140ms, (B) PR interval >160ms, (C) PR interval >180ms, (D) PR interval >200ms
Answer is D. First-degree AV block (PR interval >200 ms) is a slowing of conduction through the AV junction. All p waves will be followed by QRS complexNormal PR interval 120-200msHarrison 19e pg: 1472