So this article was published in Circulation in 2006 in corroboration between AHA, ACC, and European Society of Cardiology and is pretty authoritative. I am aware it is quite extensive and don't expect or think that many of you will read the whole thing; this is why I put a few bullet points on management of monomorphic V. Tach:
1) Class I C - Cardioversion is always the first choice in unstable v.tach (I would also consider electricity a first line choice in stable v.tach because it is quite effective and not cardiotoxic like our "antiarrhythmics").
2) Class IIa B - Procainamide is the first line recommendation for monomorphic v.tach; it is however proarrhythmic and can prolong the QT.
3) Class IIa C - Amiodarone is an acceptable agent for v.tach especially refractory to shock or procainamide.
4) Class IIb - Lidocaine can be used in pts with myocardial ischemia or infarction in v.tach.
5) Class III - Verapamil and Diltiazem should NOT be used in wide complex tachycardia of unknown origin.
* You may consider adding IV beta blocker instead of starting a drip after initial cardioversion as it may be as effective and without the cardiotoxicity.
** Caveats to the above is that wide-QRS tacchycardias I've named v.tach for convenience but may be other rhythms. Consider obtaining a magnesium level on pts with hypokalemia or possible electrolyte disturbances and giving Mg to pts in dysrhythmias. If someone is hemodynamically unstable, shock them at the max voltage.
*** When you are managing a wide complex tachyarrhythmia, it will almost always be v.tach and unless you have a good reason for calling it SVT with abberancy or pre-exitation, treat it as v.tach since it is always safer.