Can you call STEMI with LBBB?
As with all LBBB, there is a small r-wave in V1-V3 and a deep S-wave. Can you diagnose STEMI here? —Yes! The diagnosis of STEMI in the presence of left bundle branch block has been problematic for years.
Can you diagnose an MI with LBBB?
Concordance and discordance of ST segments are determined by comparison with the main direction of the QRS complex. Overall, studies have demonstrated that less than half of all patients with suspected MI and LBBB ultimately will be diagnosed with an MI.
Is new LBBB a STEMI equivalent?
Whereas in the past, the presence of new or presumably new LBBB in a patient with symptoms compatible with AMI was considered a class I indication for emergent reperfusion therapy (STEMI‐equivalent, also known as occlusion MI, or OMI), the 2013 American College of Cardiology Foundation/American Heart Association …
Can beta blockers be used in LBBB?
Patients with DCM and acceleration-dependent LBBB may benefit from restoration of a narrow QRS complex by suppressing the heart rate with beta-blocker.
Why does LBBB cause elevation?
Assessment of ischemia on ECG is difficult in the presence of left bundle branch block. This is because left bundle branch block causes substantial changes in left ventricular de- and repolarization, which result in (secondary) ST-T changes.
Why is LBBB a stemi mimic?
This is further complicated because an LBBB itself is a risk factor for cardiac death and any new LBBB can be the presenting ECG pattern in a proximal left anterior descending coronary artery (LAD) occlusion. Thus, a new LBBB ECG pattern in patients with a compatible clinical scenario is considered a STEMI equivalent.
How can you tell the difference between old and new LBBB?
Patients with new LBBB were younger, more likely to be male, and more likely to have positive TnT levels compared with the old LBBB group (corresponding TnT data were available for 93% of tracings). T-vector magnitude in the new LBBB group was larger, and QRS vector magnitude smaller compared with the old LBBB group.
Is LBBB a progressive?
LBBB most often occurs in patients with underlying heart disease and may be associated with progressive conducting system disease.
Can LBBB worsen?
For most people, this is not a big problem. But if you have underlying heart failure, left bundle branch block can make it worse. In some people, a left bundle branch block is present all the time. In others, it happens off and on, depending on the heart rate.
What are the secondary changes in LBBB?
Abnormal repolarization results in secondary ST-T changes, including ST elevations (leads V1–V3), ST depressions (leads V4, V5, V6, aVL, I) and inverted T-waves (seen in leads with ST depressions). Such ST-T changes are always normal (expected) in the presence of LBBB.
Can you assess the ST segment with LBBB?
The presence of a left bundle branch block (LBBB) on EKG can make recognition of an acute ST segment elevation myocardial infarction (STEMI) difficult.
What is the significance of LBBB?
LBBB is important because it often indicates that some form of underlying cardiac disease is present. On the other hand, right bundle branch block does not imply an underlying heart condition. Therefore, anyone diagnosed with left bundle branch block on their ECG should have a cardiac evaluation.