2. The patient is an elderly man who presented to the emergency ward with dizziness Rate – 42 bpm Normal Sinus Rhythm L axis deviation PR prolongation Widened QRS Peaked T waves #16
3.
4. This 10-second rhythm shows at least three different rhythms! Can you find them? Atrial Flutter Sinus Beat Atrial Fibrillation
5.
6.
7. Regular, Rate 93 bpm Normal Sinus Rhythm R atrial enlargement # 2
11. 85-year-old patient with valvular heart disease and congestive heart failure. #18 Regular, Rate 88 bpm P-wave downward in II, Not Sinus Rhythm Atrial rate – 220 with 2:1 AV block
12.
13. 51-year-old female with palpitations. # 5 Regular Rate 142 bpm No clear P waves before QRS – Not sinus rhythm Retrograde P-waves, with short RP interval
14. Resting ECG in a 65 year-old male with complaint of palpitations. Regular Rate 150 bpm No clear P waves before QRS – Not sinus rhythm Retrograde P-waves, with short RP interval
15. Mechanism of Reentry An impulse initiated in the SA node passes through both the AV node and the accessory pathway A premature atrial impulse occurs and reaches the accessory pathway when it is refractory, but conduction occurs through the AV node The impulse takes sufficient time to circulate through the AV node to allow the accessory pathway to recover initiating reentry
16. Mechanisms of Supraventricular Tachycardia AVNRT – the AV node is divided into two pathways and the activation of the atria and ventricle is synchronous so the retrograde P-wave is buried. Account for 60% of SVT. Usu are 150-200 bpm Orthodromic AVRT – mechanism seen on previous slide. Usually, L atrium is the first site retrograde atrial activation. Accounts for 30% of SVT Widened QRS Antidromic AVRT – activation occurs in the opposite direction resulting in wide complex tachycardia that is indistinguishable from V tach
