How To Think About Rhythms and Conduction

Transcription

1 How To Think About Rhythms and Conduction Frank Yanowitz, MD Professor of Medicine (Cardiology) University of Utah School of Medicine Medical Director, IHC ECG Services Intermountain Healthcare

2 Disclaimer: I have no financial relationships with companies that make: ECG or EKG equipment ECG or EKG paper ECG or EKG electrodes ECG or EKG Calipers ECG or EKG skin preps Treadmills & bicycle ergometers Single malt scotch

3 How To Think About Rhythms And Conduction Electrical Impulse Rhythms Site of origin: (Sinus, Atria, AV Junction, Ventricles) Rate: (Normal, Fast, Slow) Regularity: (Regular, Irregular) Onset: (Passive escape, active) Sinus node Conduction Antegrade Retrograde Atria AV Junction: (A-V, V-A) Ventricular: RBBB LBBB Wenckebach Mobitz II Anterior fascicular block Posterior fascicular block Alan E. Lindsay, MD

4 The Many Rhythms In Our Lives Site of Origin Single Events Slow Rates Intermediate Rates Fast Rates (>100 bpm) Sinus Sinus bradycardia Normal sinus rhythm Sinus tachycardia Atrial PAC s Ectopic atrial rhythm Atrial fibrillation Atrial flutter (4:1 block) Junctional (AVN, His) Ventricular PJC s J- escape beats PVC s V-escape beats J- escape rhythm (~40-50 bpm) V- escape rhythm (~35-45 bpm) Accelerated J- rhythm (~ bpm) Accelerated V- rhythm (~ bpm) Paroxysmal SVT Ectopic Atrial Tachycardia Atrial fibrillation Atrial flutter (e.g., 2:1 block) Multifocal atrial tachycardia Junctional tachycardia Paroxysmal SVT: -AVNRT -AVRT (WPW) Ventricular tachycardia Torsade de points Ventricular fibrillation

5 The Heart s Conduction System * SA NODE AV N RBB LBB ANTERIOR POSTERIOR

6 Step 3: Conduction Three Locations Three Degrees Sino-Atrial AV Junction: AV Node, His Bundle First (1 ) Always conducts, but slower) Second (2 ) Sometimes conducts, sometimes not? 2 SA Block 1 AV Block (PR >200 ms) 2 AV Block: Type I (Wenckebach) Type II (Mobitz) Third (3 ) Never conducts? 3 AV Block Intraventricular Incomplete RBBB Incomplete LBBB Type II (Mobitz) (+ preexisting BBB) LAFB, LPFB,? LSFB RBBB, LBBB RBBB + LAFB RBBB + LPFB Bilateral BBB (3 )

7 Case 1: RM: 67 year old man Transferred from Park City with chest pain and elevated troponins History of hypertension and hyperlipidemia. Coronary angiogram: totaled RCA Treatment: thrombectomy and RCA stent

8 RM: 9/18/2015 Admission ECG (after transfer from Park City)

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10 ~80 bpm J-esc J J-esc J-esc

11 RM: (9/20/2015) 2 days after admission

12 A AV V PR: 260ms 320ms 360ms ECG DX: NSR with aborted 2 nd degree AV block and atrial echo s; one fusion beat (V-escape) F ~60 bpm? PR: 260ms 320ms 360ms PR: 260ms 320ms 360ms

13 Atrial echo Venticular echo

14 Case 2 Follow The Bouncing Balls LM is a 71 year old man with history of: Atrial fibrillation Obstructive sleep apnea Diabetes mellitus HFpEF

15 20-January January-2012 (history of Paroxysmal A-fib; status post cardioversion)

16 20-January-2012 Things to note: 1) wide QRS (~160 ms) with late rightward (red) and anterior (blue) forces: i.e., RBBB 2) LAD (-70 ) with S III > S II ; i.e., a marker of left anterior fascicular block 3) Small q in V1-2 plus anterior T wave inversion: i.e., probable old anteroseptal MI ECG Diagnosis: Normal sinus rhythm (57 bpm); RBBB + LAFB;? Old anteroseptal MI; Nonspecific T wave abnormalities

17 23-April April-2013 ( confirmed ECG diagnosis: Junctional escape rhythm ) Why is this an incorrect statement? HR = 75 bpm (accelerated J-rhythm, not a passive J-escape rhythm)

18 24-April-2013 The next day: confirmed ECG diagnosis: atrial fibrillation Why is this an incorrect diagnosis?

19 24-April :1 3:1 2:1 3:1 3:1 ~ 42 bpm 3:1 3:1 (? J-esc) (? J-esc) 24-April-2013: ectopic atrial tachycardia (~180 bpm) with variable AV block

20 11-April April-2015 (17:16): ER Visit: supraventricular tachycardia (~180 bpm)

21 11-April April-2015 (17:36): while on amiodarone drip

22 11-April April-2015 (17:36): while on amiodarone drip

23 11-April-2015 A AV Green (P waves), Red (QRS s), Blue (PR intervals) V ECG Diagnosis: Ectopic Atrial Tachycardia (180 bpm) with 3:2 AV Block (type 1)

24 The Many Rhythms In Our Lives Site of Origin Single Events Slow Rates Intermediate Rates Fast Rates (>100 bpm) Sinus Sinus bradycardia Normal sinus rhythm Sinus tachycardia Atrial Junctional (AVN, His) Ventricular PAC s Atrial echo's PJC s J- escape beats PVC s V-escape beats J- escape rhythm (~40-50 bpm) V- escape rhythm (~35-45 bpm) Ectopic atrial rhythm Atrial fibrillation Atrial flutter (4:1 block) Accelerated J- rhythm (~ bpm) Accelerated V- rhythm (~ bpm) Paroxysmal SVT Ectopic Atrial Tachycardia Atrial fibrillation Atrial flutter (e.g., 2:1 block) Multifocal atrial tachycardia Junctional tachycardia Paroxysmal SVT: -AVNRT -AVRT (WPW) Ventricular tachycardia Torsade de points Ventricular fibrillation

25 Step 3: Conduction Three Locations Three Degrees Sino-Atrial AV Junction: AV Node, His Bundle First (1 ) Always conducts, but slower) Second (2 ) Sometimes conducts, sometimes not? 2 SA Block 1 AV Block (PR >200 ms) 2 AV Block: Type I (Wenckebach) Type II (Mobitz) Third (3 ) Never conducts? 3 AV Block Intraventricular Incomplete RBBB Incomplete LBBB Type II (Mobitz) (+ preexisting BBB) LAFB, LPFB,? LSFB RBBB, LBBB RBBB + LAFB RBBB + LPFB Bilateral BBB (3 )

26 Stay Up-To-Date : ECG Rhythms and Conduction Can be interesting!