My mom's ecg reads as sinus bradycardia with a single abnormal conducted beat, left axis deviation. what does that mean? she is 54 years old.

Rate <60 & Purkinje: fiber damage within endocardium. Any rate below 60 BPM is defined as bradycardia (not unhealthy). The abnormal conduction & LAD both occur as a result of damage to the Purkinje muscle fibers (look this up) within the endocardium of her heart muscle; nearly alway a result of atherosclerosis & heart attacks within the inner wall of the left ventricle-the portion most susceptible to ischemic damage.