Sudden weakness with bradycaria and bizarre T-waves

An 60-something man complained of sudden weakness. There was no chest pain or SOB. He had normal blood pressure and perfusion and was asymptomatic at rest. He was well appearing.An ECG was recorded:There is a slow, wide rhythm with bizarre T-waves.What is it? What do you want to do?You ' ll note there are P-waves.Look at lead II across the bottom:---There is a P-wave immediately after each T-wave (these do NOT conduct).---There is a P-wave immediately before each QRS. Even though it appears as if that P-wave does not have enough time to conduct, the PR interval is exactly the same for every one of these, so it is very unlikely to be isorhythmic dissociation.  Therefore, every other P-wave is conducting and it is thus 2nd degree AV block, Mobitz II.Furthermore, there is a large R-wave in V1, with large S-wave in V5-V6 (RBBB) and also an axis toward aVR, implying a fascicular block as well.We all know that there is a high incidence of progression from Mobitz II to third degree (complete) AV block, but we don ' t always get to see it.Such progression to complete heart block is especially likely when there is high degree block due to disease in the conducting fibers (in contrast to the AV node alone). And the fact that there is RBBB + fascicular block shows that there is disease in these conducting fibers also.Here only one fascicle is working, and then it is only working on every other beat!!Management: Since these patients are at high ris...
Source: Dr. Smith's ECG Blog - Category: Cardiology Authors: Source Type: blogs