This 50 year old woman presented with palpitations. There is a past history of hypertension and non insulin dependent diabetes. There was no chest pain, and her vital signs were normal.
We will begin with the rhythm strip.
Next we look at the precordial leads of the initial tracing taken at 1810.
The ECG taken at 1810 shows tachycardia-bradycardia syndrome (sick sinus syndrome), with a dominant rhythm of atrial fibrillation with a ventricular rate of 180 - 200 beats per minute. There is an intermittent, rate related, right bundle branch block.
The initial management of this case would be to slow the fast ventricular rate with a drug that will slow conduction through the atrioventricular node (AVN). We could start with intravenous magnesium, followed by digoxin or amiodarone (starting at low initial doses). I would avoid intravenous administration of more than one AVN blocking drug.
The second ECG at 1925 shows atrial fibrillation with a ventricular rate of about 100 beats per minute.