FIGURE 86.3 Supraventricular tachycardia due to an atrial ectopic focus This shows runs of SVT at a rate of 200 BPM The P waves precede the QRS complex, but not have the morphology of sinus P waves, suggesting tachycardia mediated by an ectopic atrial focus The rhythm is alternating atrial tachycardia (SVT) and sinus rhythm on this EKG, suggesting an incessant tachycardia This rhythm will not be terminated by adenosine and may be associated with dilated cardiomyopathy