Newsletter Second Degree Block & Right Bundle Branch Block A 70-year-old man is seen in the clinic because of breathlessness, which began over a few days 3 months ago. This is his ECG: what does it show and what treatment is needed? Click the button below to Download 500+ High-Yield Medical Presentations and eBooks Get Lifetime Access to 500+ Medical Presentations Answer Sinus rhythm Second degree (2:1) heart block (most obvious in lead V3) Ventricular rate 30/min Normal PR interval in the conducted beats Normal axis QRS duration prolonged (160 ms) RSR pattern in leads V1-V3and a wide S wave in lead V6 Prominent U wave in leads V3-V6 Clinical interpretation This patient has second degree block and right bundle branch block, so he clearly has extensive conduction tissue disease. What to do? The slow heart rate is probably the cause of his heart failure, and he needs a permanent pacemaker. The story suggests that the onset of heart failure was not associated with chest pain, so the underlying disease is probably fibrosis of the conducting system rather than ischaemia. He needs an echocardiogram and treatment with an angiotensin-converting enzyme inhibitor if there is evidence of left ventricular dysfunction. Share this : Library Anatomy Anesthesiology Biochemistry Cardiology Dermatology Emergency Endocrinology ENT Examinations Forensic Med. Obs. & Gynae. Hematology Medicine Microbiology Nephrology Neurology Oncology Ophthalmology Orthopaedics Paediatrics Parasitology Pathology Pharmacology Physiology Psychiatry Pulmonology Radiology Rheumatology Surgery Our mission is to provide a free, reliable and first-class education to everyone. Rish Academy is a nonprofit organization.  Every little bit counts and is appreciated. Donate Today For Users Contact us Email Newsletters Advertise here About About Rish Academy Our Mission Founder Terms and Conditions Privacy Policy Disclaimer Find us on