I always recommend seeing your cardiologist for advice regarding your health.  In regards to The NYHA functional class, it can wax and wane depending on symptoms. Class I is defined as having no limitation with activity. Left Bundle Branch Block (LBBB) is associated with Dilated Cardiomyopathy (DCM) but it is unknown whether it causes the LV dilation or the LV dilation causes the LBBB. Studies have found that patients with low ejection fraction and LBBB are more likely to have a nonischemic etiology (not caused by blocked arteries) compared to those that do not have conduction issues. Lisinopril can help heart failure independent of lowering blood pressure. It seems like you are on appropriate medications