EKG Interpretations, Schemes and Mind Maps of Cardiology

Download EKG Interpretations and more Schemes and Mind Maps Cardiology in PDF only on Docsity! EKG Interpretations Chad Link, DO FACC Cardiologist Chairman Cardiology Section Sparrow TCI Lansing, MI Disclosures EKG – 12 Leads • Anterior Leads - V1, V2, V3, V4 • Inferior Leads – II, III, aVF • Left Lateral Leads – I, aVL, V5, V6 • Right Leads – aVR, V1 11 Step Method for Reading EKG’s • “Data Gathering” – steps 1-4 – 1. Standardization – make sure paper and paper speed is standardized – 2. Heart Rate – 3. Intervals – PR, QT, QRS width – 4. Axis – normal vs. deviation Cardiology/EKG Board Review- MJ Bradley, DO 11 Step Method for Reading EKG’s • “Diagnoses” – 5. Rhythm – 6. Atrioventricular (AV) Block – 7. Bundle Branch Block or Hemiblock – 8. Preexcitation – 9. Enlargement and Hypertrophy – 10. Coronary Artery Disease – 11. Utter Confusion » The Only EKG Book You’ll Ever Need Malcolm S. Thaler, MD Cardiology/EKG Board Review- MJ Bradley, DO Intervals • Measure length of PR interval, QT interval, width of P wave, QRS complex QTc • QTc = QT interval corrected for heart rate – Uses Bazett’s Formula or Fridericia’s Formula • Long QT syndrome – inherited or acquired (>75 meds); torsades de pointes/VF; syncope, seizures, sudden death Axis AV Block • Diagnosed by examining relationship of P waves to QRS complexes • First Degree – PR interval > 0.2 seconds; all beats conducted through to the ventricles • Second Degree – only some beats are conducted through to the ventricles – Mobitz Type I (Wenckebach) – progressive prolongation of PR interval until a QRS is dropped – Mobitz Type II – All-or-nothing conduction in which QRS complexes are dropped without PR interval prolongation • Third Degree – No beats are conducted through to the ventricles; complete heart block with AV dissociation; atria and ventricles are driven by individual pacemakers Heart Blocks Constant P-R interval Variable P-R Interval First Degree Heart Block Second Degree Heart Block Type | | eared i Second Degree Heart Block Type II Third Degree Heart Block Bundle Branch Blocks • Diagnosed by looking at width and configuration of QRS complexes Hemiblocks • Diagnosed by looking at right or left axis deviation • Left Anterior Hemiblock – 1.Normal QRS duration and no ST segment or T wave changes – 2. Left axis deviation greater than -30° – 3. No other cause of left axis deviation is present • Left Posterior Hemiblock – 1. Normal QRS duration and no ST segment or T wave changes – 2. Right axis deviation – 3. No other cause of right axis deviation is present Bifascicular Block • RBBB with LAH – RBBB – QRS > 0.12 sec and RSR’ in V1 and V2 with LAH – left axis deviation • RBBB with LPH – RBBB – RS > 0.12 sec and RSR’ in V1 and V2 with LPH – right axis deviation Preexcitation • Wolff-Parkinson-White (WPW) Syndrome – 1. PR interval < 0.12 sec – 2. Wide QRS complexes – 3. Delta waves seen in some leads • Lown-Ganong-Levine (LGL) Syndrome – 1. PR interval < 0.12 sec – 2. Normal QRS width – 3. No delta wave • Common Arrhythmias – Paroxysmal Supraventricular Tachycardia (PSVT) – narrow QRS’s are more common than wide QRS’s – Atrial Fibrillation – can be rapid and lead to ventricular fibrillation Teo lt I Atrial fibrillation Afib with Rapid Ventricular Response (RVR) eo ot ey (sf re Pots Pet Atrial flutter es ag al Poa BLRoR Hetero van LULA Sc Tee Peel el eiabe Papa pe ie eh Multifocal atrial tachycardia TABLE 4-3 CHARACTERISTICS OF SUPRAVENTRICULAR TACHYCARDIA (SVT) Rate 150-250 beats/min Rhythm Regular P waves Atrial P waves may be observed that differ from sinus P waves PR interval If P waves are seen, the PRI will usually measure 0.12-0.20 sec QRS duration Less than 0.10 sec unless an intraventricular conduction delay exists Rules of Aberrancy Ventricular Tachycardia Paroxysmal supraventricular Tachycardia Clinical Clues Clinical History Diseased heart Usually normal heart Carotid Massage No response May terminate Cannon A Waves May be present Not seen EKG Clues AV Dissociation May be seen Not seen Regularity Slightly irregular Very regular Fusion Beats May be seen Not seen Initial QRS deflection May differ from normal QRS complex Same as normal QRS complex Ventricular Arrhythmias Torsades de Pointes PVC’s Myocardial Infarction • Dx – Hx, PE, serial cardiac enzymes, serial EKG’s • 3 EKG stages of acute MI – 1. T wave peaks and then inverts – 2. ST segment elevates – 3. Q waves appear Q Waves • Criteria for significant Q waves – Q wave > 0.04 seconds in duration – Q wave depth > ⅓ height of R wave in same QRS complex • Criteria for Non-Q Wave MI – T wave inversion – ST segment depression persisting > 48 hours in appropriate clinical setting Localizing MI on EKG • Inferior infarction – leads II, III, aVF – Often caused by occlusion of right coronary artery or its descending branch – Reciprocal changes in anterior and left lateral leads • Lateral infarction – leads I, aVL, V5, V6 – Often caused by occlusion of left circumflex artery – Reciprocal changes in inferior leads • Anterior infarction – any of the precordial leads (V1- V6) – Often caused by occlusion of left anterior descending artery – Reciprocal changes in inferior leads • Posterior infarction – reciprocal changes in lead V1 (ST segment depression, tall R wave) – Often caused by occlusion of right coronary artery Electrolyte Abnormalities on EKG • Hyperkalemia – peaked T waves, prolonged PR, flattened P waves, widened QRS, merging QRS with T waves into sine wave, VF • Hypokalemia – ST depression, flattened T waves, U waves • Hypocalcemia – prolonged QT interval • Hypercalcemia – shortened QT interval Drugs • Digitalis – Therapeutic levels – ST segment and T wave changes in leads with tall R waves – Toxic levels – tachyarrhythmias and conduction blocks; PAT with block is most characteristic. • Multiple drugs associated with prolonged QT interval, U waves – Sotalol, quinidine, procainamide, disopyramide, amiodarone, dofetilide, dronedarone, TCA’s, erythromycin, quinolones, phenothiazines, various antifungals, some antihistamines, citalopram (only prolonged QT interval – dose-dependent) EKG ∆’s in other Cardiac Conditions • Pericarditis – Diffuse ST segment elevations and T wave inversions; large effusion may cause low voltage and electrical alternans (altering QRS amplitude or axis and wandering baseline) • Myocarditis – conduction blocks • Hypertrophic Cardiomyopathy – ventricular hypertrophy, left axis deviation, septal Q waves Other Important Points • Verify lead placement • Repeat EKG • Repeat standardized process of EKG analysis- starting over from the beginning with basics – rate, intervals, axis, rhythm, etc. and proceed through entire stepwise analysis Arrhythmia Indications to Consult Cardiology • Diagnostic or management uncertainty • Medications not controlling symptoms • Patient is in high-risk occupation or participates in high-risk activities (pilot, scuba driving) • Patients prefers intervention over long-term meds • Preexcitation • Underlying structural heart disease • Associated syncope or other significant symptoms • Wide QRS Care Considerations Prior to Cardiology Consult • Thorough Hx and PE • Basic labs • EKG and repeat EKG • Holter monitor • Echocardiogram • Acuity of care required – consider risks, hemodynamic stability Clinical Cases/EKG’s Case 1 • A 59 year old male develops an acute onset tachycardia while watching the Super Bowl. He admits to “having a few beers” and has a heavy smoking history. His pulse rate is 150 beats per minute and quite regular. 080837 07/08/2016 Room: 2 Oper: SB Rate PR ORSD or ore rs. PA NEY { NLA | | data th dL ep pefiataltta ap lal al a Log 000p040000! Speed: 25 Himb: {0 im/m¥ | Chesit WP7ve) 00935 Case 2 • A 19-year-old student athlete presents for a sports physical. He is on no medications. On physical exam: BP: 110/85 mm Hg; HR: 55 bpm; pulse rate is intermittently irregular. poeesiprerbbhly bce Mabe tcte • Myocardial infarction (STEMI) • Acute pericarditis • Benign early repolarization • Ventricular aneurysm • Coronary vasospasm (Prinzmetal Angina) EKG Differential Diagnosis ST Segment Elevation Case 4 • A 22 year old medical student presents to the Health Center complaining of palpitations. She has just taken her Cardiology Final Exam, and admits to considerable stress and lack of sleep over the past few days. Case 4 Cardiology/EKG Board Review- MJ Bradley, DO Case 5 • Acute anterior ST-elevation MI with “tombstone” or “fireman’s hat” in V1-V4 • Tx? Localization? Case 5 • PCI stenting of LAD • Post-procedure = resolving ST elevation; loss of ominous tombstone effect; Q waves developing Cardiology/EKG Board Review- MJ Bradley, DO Case 6 • 50 yo male presents with acute SOB s/p long vacation in Paris • PMHx - GERD, tobacco abuse • VS- 150/90, 140, 30 • Patient appears uncomfortable but otherwise unremarkable exam Case 7 • 75 yo male presents to the office for evaluation prior to colonoscopy • No complaints • PMHx –HTN, hyperlipidemia, and chronic low back pain • VS- 160/80, 76, 16 Case 7 Cardiology/EKG Board Review- MJ Bradley, DO Case 7 • LVH – QRS voltage criteria in precordial leads and repolarization changes in V5, V6 Case 8 • SVT – regular, narrow-QRS tachycardia, rate of 160 bpm • Etiology – Ischemic heart disease – Digoxin toxicity – Excessive caffeine/amphetamine – Excessive ETOH – Atrial flutter with RVR Supraventricular tachycardia WHAT IS YOUR NEXT STEP IN MANAGEMENT? Supraventricular Tachycardia • Treatment – Maneuvers to increase vagal tone and delay AV conduction to block reentry • Valsalva maneuver • Carotid sinus massage • Breath holding • Head immersion into cold water – Pharmacotherapy • IV adenosine = agent of choice –Decreases sinoatrial and AV nodal activity • IV verapamil, IV esmolol/propranolol/metoprolol, digoxin – DC cardioversion if unstable or meds ineffective • Prevention – Verapamil, Beta-blockers – Radiofreqency ablation Case 9 • Normal EKG Case 10 • 49 yo female presents to primary care physician with c/o dizziness and occasional palpitations in her chest • PMHx – anxiety, depression, obesity • Works as secretary • VSS normal Case 10 Cardiology/EKG Board Review- MJ Bradley, DO eee Prey. ay << 8 r te Tt Pid = fue av 8! JAY PO ots } Case 11 • Typical preexcitation (WPW) pattern • Short PR interval and delta waves in many leads • Tx is close observation unless patient has had SVT or atrial fibrillation which indicates tx with ablation of accessory pathway Case 12 • 56 yo male presents to ED with c/o feeling sick for the last 6 days • Symptoms include shortness of breath and chest pain • PMHx – DM, hyperlipidemia • VS - tachycardic Case 13 • 75 yo male presents to the office for post hospital follow up • No significant PMHx • Medications– ACE inhibitor, beta blocker, aspirin and a statin INP ATI Ta hoo ell = $a} Y ¢ +t VEL nd AL teal 2 i ji | Ty i Ate Ym ten YT iy woe sh etter ey \ ! i+ pete ee ESE | + Case 13 • Atrial fibrillation – irregularly irregular without P waves • RBBB – wide QRS with rsR’ pattern in V1, broad S waves in leads I and aVL • Inferior infarct – non-acute (> 1 week) pathologic Q waves in inferior leads (II, III, and aVF) Case 14 • Monomorphic sustained ventricular tachycardia (VT) – could rapidly deteriorate into VF, torsades de pointes, asystole, or sudden death Case 15 • 85 yo female admitted the hospital for chest pain • PMHx – HTN, PAD, Hyperlipidemia, DM2, CHF, obesity, depression Case 15 Cardiology/EKG Board Review- MJ Bradley, DO A LH | P| AAA AA aly AL AK JALAN A Ra MC} wr i Vet Eee ey Sra Case 16 • Hyperkalemia – tall peaked T waves present throughout; other progressive EKG changes may follow with increasing potassium levels – prolonged PR interval, flattened P waves, widening QRS, sine waves • Sinus tachycardia also present Case 17 • 18 yo male undergoing physical exam • No complaints • PMHx – denies • VSS-unremarkable