broad complex tachycardias
AV nodal blockers, particularly, verapamil, but also adenosine, may cause VF if given to patients with WPW
with broad complex tachyarrythmias unless it is definetely antidromic AVRT and not AF or atrial flutter
acute Mx of broad complex tachycardia:
oxygen, cardiac monitor, resuscitation facilities on hand, correct electrolyte disturbances if present
could it be sinus tachy with wide QRS?
if unlikely to be sinus tachy, but is haemodynamically unstable then immediate DC reversion
if haemodynamically stable then:
DDx of wide complex tachycardias:
An RS (from the initial R to the nadir of S) interval longer than 100 ms in any precordial lead is highly suggestive of VT.
A QRS pattern with negative concordance in the precordial leads is diagnostic for VT (“negative concordance” means that the QRS patterns in all of the precordial leads are similar, and with QS complexes). Positive concordance does not exclude antidromic AVRT over a left posterior accessory pathway
The presence of ventricular fusion beats indicates a ventricular origin of the tachycardia.
QR complexes indicate a myocardial scar and are present in approximately 40% of patients with VTs after myocardial infarction.
c_broadcomplextachy.txt · Last modified: 2019/01/09 11:16 by wh