(BQ) Part 2 book Goldberger’s clinical electrocardiography has contents: Digitalis toxicity, limitations and uses of the ECG, sudden cardiac arrest and sudden cardiac death syndromes, pacemakers and implantable cardioverter defibrillators - essentials for clinicians,... and other contents.
CHAPTER 19 Bradycardias and Tachycardias: Review and Differential Diagnosis Preceding chapters have described the major arrhythmias and atrioventricular (AV) conduction disturbances These abnormalities can be classified in multiple ways This review/overview chapter categorizes arrhythmias into two major groups: bradycardias and tachycardias The tachycardia group is then subdivided into narrow and wide (broad) QRS complex variants, which are a major focus of ECG differential diagnosis in acute care medicine and in referrals to cardiologists rest) or to actual SA block (see Chapter 13) Inappropriate sinus bradycardia may be seen with the sick sinus syndrome (discussed below) The most extreme example of sinus node dysfunction is SA node arrest (see Chapters 13 and 21) As now described, sinus bradycardia may also be associated with wandering atrial pacemaker (WAP) In addition, sinus rhythm with atrial bigeminy—where each premature atrial complex (PAC) is blocked (nonconducted)—may mimic sinus bradycardia BRADYCARDIAS (BRADYARRHYTHMIAS) Wandering Atrial Pacemaker The term bradycardia (or bradyarrhythmia) refers to arrhythmias and conduction abnormalities that produce a heart rate 1icity and, 212 - 213, 213f Bifascicular blocks, 70- 72 , ?If Biphasic, 11 , 12f dellcctiOll, 32 , 33/ BiV See Bivennicular pacemakers Bivcntricular hypertrophy, 60 Index Biwnrrkular (BiV) pacemakers, 232, 233f fusion -type QRS complexes and , 232, 234f Bivennicular pacing, 226 Blocked PAC, 132, 132{ Box counting methods, 17/, 18 Brady-asysrolic rhythms cardiac arrcsiand, 218-221 hyperkalc111ia and , 221 Bradycardias, 194 197 SeealsoSinus bradycardia AF or AFl with slow ventricular rate, 196-197, 197/ AV heart block, 195 196, 196{ AV junctional escape rhythm , 195, 196{ dassification, 195b differemial diagnosis, 258b dig italis toxiciryand, 212 idioventricu!arcscapc rhythm, 197 overview, 194 llrugada ~yndromc , 222- 223, 224J Bunclle branch blocks, 191 Sec also Left bundle branch block; Right bundle branch bloc k Bu11dleofHis,_3_ 3f BrfJass nacts Seet1lso \Vo lff- Park inson - White AVRT and , 139 concealed, IJ9, 186 defined, 183 localization o( !86, 186b manifest, 139, 186 prcexciration via AV, 183, 184{ Calcium channel blocker, 209 drugeffecrs, 105 Calibration mark $cc Standardization mark Calipers test , 150, 151{ Capture bea t , VTs and , 206, 206{ Ca rdiac anatom ic position, 46 Cardiac arrest Sec alw Sudden cardiac arrest artifacts and , 219{.221 13'-ady-asysrolic rhyd1ms in, 218-22 l Brugada syndrome and , 222-223, 224f causes of, 221 225 , 222b clinical aspects of, 217 cormnotiowrdisand , 225 CPRand , 17, 218b CPVT and , 223 225, 224f defined , 217 diagnostic signs of, 117b differential diagnosis , 260b drug SeealsoMyocardial ischemia lsoclcctric, II , 12[ lsor11yrhmiCAV dissociarion , 181{, 182 pitfalls rclatcd to , 252 IVCD See lntravcntricular conduction delay J poim, 14, 14f elevatlO!l or depression, 15 Juvenile T wave inversion p:i[tcm, IOI Knuckle sign Sec Pl{-ST segment discordance sign LA.See Left atrium LAA Sec Left atrial abnormality LAD Sec Lcft anterior desccnd ing; Lefr axis deviation LAFll.SecLefranteriorfascicular block LBBB Sec Left bundle branch block Leadlesspacemakers, 226 Leads Scealw Chcsr leads; Limb leads bedside monitors and, 28 30, 29[ electrode placemem, 29 , 29[ fronta l plane, 27- 28, 28[ mean QRS axis and 41 , 42[ sinus Pwaveand, 33 34, 33f l1exaxial diagram , 41, 42f horizomal planc, 27- 28, 29[ M!and,28,83b monitors, cardiac, and, 28- 31 oricnration of, 25 overvicw, paccmakers and, 226 polarity of ~ 12-lead ECG, 27-28 v ,,67b Left antcrior desccnding (lAD), 100, lOOf Left anterior fascicular block (LAFB) axis deviation and, 68 69 bifascicular blocks and, 70 72, 71J diagnosis of, 69, 69f QRS vector shifrs in , 61, 62b RBBB with, 69, 70f tr ifascicularblocks and, 70 72 Left atrial abnormality (LAA), 51 - 53 clinical occurrence of 52b IACD and, 53 P wave and 1- 52, 52f- 53f patterns of 53f PT I'Vl and, 53 Index Left arrium (LA) , 3[ Left axis deviation (LAD) clinical significance related to, 48- 49, 49{ dcfined, 46 difforcntial diagnosis, 254b horizontal QRS axis and, 47 recognition , 6- 47, 47f- 48f venical QRSaxisand, 47 Left bundle branch block (LBIHI) clinical significance, 66 67, 66b complete and incomplete, 66 depolar ization sequence in, 64-65, 64{ differential diagnosis, 67 68 of wide QRS complex patterns and , 191 enlargement diagnosis in presence of, 72 example of, 65 , 65[ Hf' and, !18 ICVD and, 65 , 67[ intrinsic IVCDand ,68 LVH and,57- 58 MI diagnosis in presence of, 72, 88- 91 , 90[ !llononiorphic vrs and, 206b pitfalls related to, 252 QRS complex and, 64 67 QRSvectorshiftsi11 , 6! , 62b JUH313 compared with , 65, 66[ rrifoscicula1· blocks and, 70-72 trifascicular conduction system and, 68, 68[ V1 lead and, 67b ventricular conduction disturbances and , 64- 67 VTsand, 68 VTs with aberration and, 201, 201f- 202f Left postnior fascicular block (LPFB) diagnosisof, 69- 70 QRSvectorshifrs in , 6!,62b RBBB with, 70, 1/ Leftventrick (LV) electrophysiology and, 3f enlargement, 56- 58 Left ventricular hypertrophy (LVH), 56-58 bivenrricular hypertrophy and, 60 clinical perspectiveand,59 60, 59b 60b diagnosis, 56-58 ECG feamres affected by, 56 HF and, l 18 IVCDand, 5758 LBBB and, 57- 58 pattern of 58/ prognosisand, 60 recognition, value of, in , 59- 60 repolarization abnormalities associated with, 59f Leftventricularhypertrophy(LVH) (Gmtin1 AF and, 146- 149 atrial flutter, 144- 146 classificat ion, 131f general p rinciples, 130 mcchanisn1so f, 130, 13 lf PACs 130-132 pathophysiologic key concept, 130b PSVfs, 132 !42 Supraventricular premature bears, !30-132 Sccaho Premarure atrial complexes Supraventricular tachycardia (SVT) See alw Paroxysmal suprave11tricula1 tachycardia:; with aberration clinical considerarions,202 considerations, 202- 209 diagnostic dues , 202- 209 LBBl3 and, 201, 201f 202f Vfsdifferentiarcd from , 200- 202 WCTs and, 200 cla:;sesof, l98 criteria favoring vrs and 208b diffcrenrial diagnosis, 1421 morphology and, 206, 207f QRS complex and, 198b QRS duration and, 206- 207 renninology confusion and, l9 with\'{IPW, 201 202 Sustained monomorphic Vfs, J64f clinical subsrratcs, 1681 !C D therapy and, 166 no organic heart disease and, 168 organic heart disease and, 168 Sustained polymorphic Vfs bidirectional ventricular tachycardia and, 169 clinical substrarcs, 169t with TdP, !69 withom Td P, 169 SVl".SecSupraventricular tachycardia Sympathetic simulation, 124 Synchrony,226 Syncope, 249- 250 Systemic circulation, T Twavc asbasicwavefor111, 6-8, 7f as graph component, 8, Sf interpretation, 243 111vcrs1011s acurc pericardiris and, l 15, ISf cardiacmemory, 233 coronaryreperfusion and, 102 differential diagnosis, 258b juvenile T wave inversion pattern, 101 LAD T -wavc pattern and , 100, !OOf Ml and, 100- 101 non-Q wave infarction and, 95, 9Gf _subarachnoid hemorrhage and, 101 , !Ulf \Vellcns' syndrome and, 100, IOOf meanclcctricalaxisof,49 measurement of, 14f J_i normal,40 RVH and, 54, 56f 57f tall, positive differentia l diagnosis, 258b Tachyarrhyrhmia.235-237 Sualso Ventriculartachyarrhythmia Tachy-brady syndrome, 209[, JO Tachycardias, 197- 210 SeeahoAtrial tachycardia; 1\rrioventricular nodal reentrant tachycardia; Atrioventricular reentr:uu tachycardia; Sinus tachycardia; 5pccificrypc5 additional clinical perspectives, 209- 210 classification of, !97t digitalis roxicityand , 212 drugs and, 209- 210 first step in ana lyzing, 198b NCTs differential diagnosis and, 198- 200 rccntryand, 4-5 Takoc:subo cardiomropathy, 97-99, 98f Tamponade, PEA and, 22 ib TdP See Torsades de poimes Tension pneumorhorax, PEA and, 22lb Third-degree i\V block, 174- 175, 175f- 176f key features, 175b Thrombocmbolic and cardiac function complications, 153 Thromboembolism, PEA and, 22 Ib Thrombosi_s myocardial infarction PEA and, 22Jb Thyroid diseasc, 248 Tiered diaapy, 235, 236f Timc-vo!tagecl1art, _l Torsades dc poinres (TdP) acquired long QT syndrome and, 167 hallmark of, !66 hereditary long QT syndromes and, 167- 168 management of, 167- 168 nonsustained, 167f as polyn101-phicVfs, 166-168 QT prolongation syndromes and, 222, 223{ sustained, 167f polymorpl1ic vrs with, 169 polymorphic Vfs without, 169 TPsegmcnt, TranscutancOi.1s pacing, 219 Transirion zone, 37- 38, 37f Transmural ischem ia, 73 -74, 74f Triads ECG, 244b, 245 QRS and, 55b usefu[ , 245 WP\Vand, 183- 186 Trifascicular blocks, 70- 72 Trifascicular conduction system, 68, 68f l :J_ AV block withAFI, 251 cautions regarding, 178 explained, 177-178 PR inrerval prolonged and, 178, 178f QRS widening and, 178, I 78f second-degree AV block and, 177- 178 Uwaves as basic waveform, 6- , 7f as graph component, 6~8 , Bf inrerprctation, 243 measurement of, 17 pitfalls related ro;-252 Unifor111 PVCs 161-162 Unipolar leads, 21 24-25, 24f Upward deflection, 11 , l2f Utility,ofECG, 247 =249 acute pulmonary embolism and 1'IB aortic valve diseaseand, l:lli_ ASD and, 248 chronic lung disease and, 248-249 as clue to lifo-threarening conditions without heart or lung disease, 248b dilated cardiomyopathy and, 249 hyperkalemia and, 248 M!and, 247- 248 mitral valved iseaseand, 248, 249{ renal failure and, 248 - thyroid disease a1~~ Index Valsalvamaneuvcr, 142- 143 Vasospastic angina Sec Prinzmeral's (variant) angina Ventricular aneurysm, Ml and , 87, 87{ Venn icular arrhyd1mias overview, 156 PVCs 156- 163 Vcnnicu lar aqstolc rhythms 218-221 Vcnnicularbigcminy, 157-158, 158[ 159[ digitalis toxicity causing, 213f Ventricu lar conducrion disturbances general principlcs, 61 hemiblocks and , 68 72 LBBB and , 64 67 overvicw,61 RBBB and, 61- 64 Ventricular depolarization direction 46 Ventricu lardyssynchro ny, 232 Ventricu lar fibrillation (VF), 170- 171 cardiac arrest and , 217- 2!8, 218{, 220[ as cardiac arrest shockable rhythm , 18, 220[ dassificarion of, 170-171 examples of, !64{, 170[ idiopathic, 225 Vl'ntricular myocardium anatomy, 35 depo larization and , 35, 35{-36[ Ventriculartachyarrhythmia, 217218 Brngada syndrome and , 222-223, 224{ Ventricular tachycardias (VTs) Sec also Monomorphic \/Ts; Polymorphic \ITs; Sustained monomorphic \ITs; Sustained polymorphic \ITs with aberr:uion LBBB and , 201, 201{-202{ svr differentiated from , 200- 202 WCT differential diagnosis and , 200 appearance and , 163 bidirectional, 212 - 213, 213[ Ventricular tachycardia.> (\/Ts) (Gmtin1