Start with very basics: what is irregularly irregular EKG? No P wave, regular Rapid, what are 3 DDx? No P wase regular SLOW, what are the three? Wide QRS tachycardia, use Brugada criteria for SVT with aberrancy vs VT (Table 9.1). MI with LBBB, then Sgarbossa score (Table 9.5). What are the ten (eleven) cases of ST elevation other than MI (Table 9.4)? When you see a wire in the heart, you should be able to tell which one it is, Dual chamber pacer, ICD, CRT? If you identify which one of these are, then you can guestimate patient’s cardiac history.