Bundle Branch Block Left Evaluation
The evaluation of a left bundle branch block starts with a history and physical examination.
The physical exam is usually normal in someone with left bundle branch block.
The diagnosis of left bundle branch block is made on an electrocardiogram (EKG) or heart monitor.
Tests that may be used to evaluate left bundle branch block may include:
- Kidney profile
- Chest x-ray
- Drug screen
- Cardiac monitoring
- Cardiac enzymes if a heart attack is suspected
- Exercise stress test
- Holter monitor:
- A portable ECG that measures the heart's rate and rhythm over a 24-hour period (or longer)
Additional tests that may be used to evaluate left bundle branch block include:
- Electrophysiologic studies:
- Electrical testing of the heart
- Used to detect abnormal conduction pathways
- Cardiac catheterization
- MRI scan of the heart:
- Shows detailed images of the heart and coronary arteries
- Detects structural abnormalities of the heart
- SPECT scanning of the heart:
- Detects blood flow abnormalities to heart muscle
- Thallium heart scan
- Coronary artery CT scanning:
- Checks for possible obstructions in the coronary arteries
- Can show a build-up of calcium in a coronary artery
- MUGA scan
Bundle Branch Block Left EP Studies
Electrophysiologic, or EP, studies of the heart may be performed on those with left bundle branch block during cardiac catheterization. This procedure uses tiny sensors to measure electrical impulses in the heart.
Continue to Bundle Branch Block Left Treatment
- Guerrero M, Harjai K, Stone GW, Brodie B, Cox D, Boura J, Grines L, O'Neill W, Grines C. Comparison of the prognostic effect of left versus right versus no bundle branch block on presenting electrocardiogram in acute myocardial infarction patients treated with primary angioplasty in the primary angioplasty in myocardial infarction trials. Am J Cardiol. 2005 Aug 15;96(4):482-8. 
- Lee SJ, McCulloch C, Mangat I, Foster E, De Marco T, Saxon LA. Isolated bundle branch block and left ventricular dysfunction. J Card Fail. 2003 Apr;9(2):87-92. 
- Nguyen K, Cigarroa JE, Lange RA, Hillis LD, Keeley EC. Presence and extent of angiographic coronary narrowing in patients with left bundle branch block. Am J Cardiol. 2004 Jun 1;93(11):1426-7, A10. 
- Reuben AD, Mann CJ. Simplifying thrombolysis decisions in patients with left bundle branch block. Emerg Med J. 2005 Sep;22(9):617-20.