Basic Electrocardiography Normal and abnormal ECG patterns - Part 8 doc

P1: OTE/SPH P2: OTE BLUK096-Bayes de Luna June 7, 2007 21:23 120 Chapter 12 Table 19 Most frequent causes of QRS-T alternans. QRS complex alternans Rarely in relation with respiration especially in mid-precordial leads Cardiac tamponade Supraventricular arrhythmias in WPW syndrome ST–T alternans Hyperacute phase of severe myocardial ischaemia Congenital long QT syndrome Electrolytic imbalance A B C V 3 V 1 II Figure 107 (A) Typical examples of electrical alternans. (A) Alternans of QRS in a patient with pericardial tamponade. (B) ST–QT alternans in Prinzmetal angina. (C) Repolarisation alternans in important electrolyte imbalance. P1: OTE/SPH P2: OTE BLUK096-Bayes de Luna June 7, 2007 21:24 Self-assessment To confirm whether you have understood the book and to check your ECG interpretative skills, we will proceed by conducting a multiple-choice test. In this test, you will be asked to give a correct answer based on presented ECG recordings. The examples of ECG tracings are based on the contents displayed in the book. The correct answers as well as comments and explanations will be given. A V1 V2 V3 B C Case 1 A young, asthenic man with no apparent heart disease. The figure shows an ECG tracing in V1, V2 and V3 leads located in the second (A), third (B) and fourth (C) intercostal space. What is the correct diagnosis? A Atrial septal defect B Partial right bundle branch block C Brugada’s syndrome D False image of right bundle branch block 121 P1: OTE/SPH P2: OTE BLUK096-Bayes de Luna June 7, 2007 21:24 122 Self-assessment Answer to Case 1 Comment. (A) Normal ECG recording, except V1, where final R wave is quite prominent and final r in V2 and RS morphology in V3 are present. Due to this morphology in V1 it is necessary to rule out RBBB. The evidence that the P wave in V1 is completely negative made us think that V1 lead is placed higher (second right intercostal space) and is recording the tail of the P vector (negative P) and the head of the third vector of ventricular depolarisation (terminal R). The lower location of the lead (B) decreased this image and it totally disappeared (positive P wave and rS in V1) when the lead was located correctly in fourth right intercostal space (C). We can conclude that in this case a false pattern of RBBB is present due to incorrect position of V1–V2 leads. The correct answer is D. Occasionally, the Brugada syndrome can present similar morphologies to ‘A’ and also the morphology may change depending on the lead position; but in the Brugada pattern the r  in V1 is wider and ST-segment elevation in V1–V2 is present (see Table 4). P1: OTE/SPH P2: OTE BLUK096-Bayes de Luna June 7, 2007 21:24 Self-assessment 123 I III II VR VL VF V 1 V 4 V 2 V 3 V 5 V 6 Case 2 A 27-year-old man with no apparent heart disease. What is the correct diagno- sis? A Acute pericarditis B Early repolarisation in a subject with a horizontal heart with levorotation C Acute phase of a myocardial infarction D Dextrorotated heart P1: OTE/SPH P2: OTE BLUK096-Bayes de Luna June 7, 2007 21:24 124 Self-assessment Answer to Case 2 Comment. There is important levorotation (Rs in V2) with mild ST-segment elevation starting from the J point, visible in V2–V4. This pattern corresponds to theso-called early repolarisationpattern. Inthe frontalplane withhorizontal heart we can see qR in VL and rS in VF with ˆ AQRS approximately −15 ◦ and in the horizontal plane levorotation is present (Rs in V2 and qR in V4). The exercise test normalises the ST-segment elevation in the early repolarisation pattern as it happened in this case, but not in acute pericarditis or the acute phase of MI. Thus, the correct answer is B (see Figures 22D and 25-2a). P1: OTE/SPH P2: OTE BLUK096-Bayes de Luna June 7, 2007 21:24 Self-assessment 125 I III II VR VL VF V 1 V 4 V 2 V 3 V 5 V 6 Case 3 An 18-year-old lean man, asymptomatic, with no heart disease. What is the correct diagnosis? A Left ventricular enlargement B Normal ECG variant; vertical heart with apparent levorotation C Normal ECG variant; horizontal heart D Normal ECG; heart with no rotation P1: OTE/SPH P2: OTE BLUK096-Bayes de Luna June 7, 2007 21:24 126 Self-assessment Answer to Case 3 Comment. Vertical heart but without dextrorotation (there is no S in V5–V6). On the contrary, it seems that there is levorotation, as large R (Rs) in V2–V3 is seen. This can be explained knowing that in lean individuals with a long and narrow thorax, the heart is located more in the centre of the thorax and V3 already faces the left ventricle. ST-segment elevation in V2–V3 from the early repolarisation type (asymmetric T wave) is seen. The high voltage of the RwaveinV4isstriking(>30 mm). This value is higher than the accepted as normal for adults, but can be observed in teenagers without heart disease and with normal echocardiogram, as it is in this case. Thus, the correct answer is B (see Figures 22D and 25.1A). P1: OTE/SPH P2: OTE BLUK096-Bayes de Luna June 7, 2007 21:24 Self-assessment 127 A B –120° –90° –60° –30° +30° +60° +90° +120° +150° –150° + 180° – 0° I III ÂQRS first part +30°, +40° ÂQRS second part -140°, -150° II VR VL VF Case 4 A 28-year-old very lean man, withslight pectus excavatum,but with no apparent heart disease. What is the correct diagnosis? A Right ventricular enlargement B Normal heart with rotation on transversal axis (S I ,S II ,S III ) C Superoanterior hemiblock D Vertical heart P1: OTE/SPH P2: OTE BLUK096-Bayes de Luna June 7, 2007 21:24 128 Self-assessment Answer to Case 4 Comment. ECG recording with S I S II S III morphologies in the frontal plane. Similar morphologies can be seen in right ventricular enlargement and, proba- bly,in the right superoanterior zonal block (see Table 6). The absolutely normal appearance of the P and T waves supports a normal heart with rotation type S I ,S II ,S III (transversal axis) (p. 26). The presence of RS in V5–V6 is due to additional dextrorotation. The extreme left deviation of ˆ AQRS, in the case of superoanterior hemiblock, generates morphologies with S II and S III but with S III > S II , on the contrary, that in this case (see Figure 43B). The normal clinical observation of the patient, including the echocardiography and the absence of pulmonary involvement, also the age and the presence of pectus excavatum, together with the normal P and T waves, supports the diagnosis of the normal heart with rotation on the transversal axis. The vertical heart presents RS in I and qR in II and III. Above: the QRS loop in such cases and the method of ˆ AQRS calculation from the first and the second part of QRS. Thus, the correct answer is B (see p. 26 and Figure 43B). P1: OTE/SPH P2: OTE BLUK096-Bayes de Luna June 7, 2007 21:24 Self-assessment 129 I IIIII VR VL VF V1 V4 V2 V3 V5 V6 Case 5 A 35-year-old man with no apparent heart disease. What is the correct diagno- sis? A Heart with no apparent rotation B Vertical heart C Horizontal heart D Indeterminate electrical axis [...]... A (see p 30 and Figure 27A) Self-assessment 133 V1 V2 Case 7 These are leads V1 and V2 of a 60-year-old woman with a heart disease Which is the correct diagnosis? A Lateral myocardial infarction B Significant enlargement of right cavities C Complete right bundle branch block D Type-II Wolff–Parkinson–White syndrome 134 Self-assessment Answer to Case 7 Comment This ECG belongs to a 60-year-old patient...130 Self-assessment Answer to Case 5 ˆ Comment ECG of a heart without apparent rotations AQRS at +30◦ (rs in III ˆ and qR in VL and VF) The rest of the recording is in the normal range AP = ˆ 0◦ , AT = + 30◦ Thus, the correct answer is A (see p 26 and Figure 24A) Self-assessment I VR V1 V4 II VL V2 V5 III VF V3 131 V6 Case 6 A 6-year-old child with no apparent heart disease... 35 and p 40) Self-assessment I VR V1 V4 II VL V2 V5 III VF 135 V3 V6 Case 8 This is a 45-year-old patient suffering from a heart disease, with the diagnosis having been made 30 years ago Which is the correct diagnosis? A Significant left ventricular and atrial enlargement B Complete left bundle branch block C Superoanterior hemiblock D Acute septal infarction 136 Self-assessment Answer to Case 8 Comment... Comment This ECG belongs to a 60-year-old patient with a long-standing mitral and tricuspid valve disease, with a significant right ventricle and atrial enlargement (see the low-voltage qR pattern in V1 and the rS pattern in V2 with a much higher voltage) The patient was in atrial fibrillation, with not visible ‘f’ waves Spontaneously, she converted to normal sinus rhythm with a P wave that was only visible,... correct diagnosis? A Normal ECG B Right ventricular overload C Left ventricular enlargement D Pericarditis 132 Self-assessment Answer to Case 6 ˆ Comment Normal ECG for the age of the patient Observe the right AQRS, the relatively tall R wave in V1 greater than ‘q’ in V6, the R wave of large voltage in V4–V5, the deep ‘q’ wave in III, the infantile repolarisation, etc The ECG is normal Thus, the correct... septal infarction: there is no QS complex in V1–V2, and the ST-segment elevation, which is convex with respect to the isoelectric baseline, may be explained as a mirror image of the LVE morphology that is seen in V6 (see p 37 and p 44) Self-assessment I VR V1 V4 137 X V2 II III VL V5 Y V6 VF V3 Z Case 9 This is a 65-year-old patient The history taking is normal, with antecedents of chronic obstructive... with a valvular heart disease presenting a significant left ventricular enlargement (LVE), with a pure R wave in lead V6 with a systolic overload pattern and an S wave in V2 + an R wave in V6 = 45 mm The P wave is wide and ± in leads II, III and VF, and from V1 to V4 It corresponds to a typical complete interatrial block with left atrium retrograde conduction that is always associated with left atrial... presence of a significant atrial fibrosis could explain that large atria, as demonstrated in the echocardiographic study, generate a barely visible voltage in the surface ECG Occasionally, even normal sinus rhythm can be completely concealed The ECG does not show the presence of a complete right bundle branch block, as the QRS complex is narrow, nor does it show the presence of a Wolff–Parkinson–White syndrome,... obstructive pulmonary disease dating back more than 20 years (recently with an acute crisis) Which is the correct diagnosis? A Right ventricular and atrial enlargement B Complete right bundle branch block C Acute coronary syndrome with a negative T wave from V1to V3 D Normal variant (vertically orientated heart) with no associated disease . OTE/SPH P2: OTE BLUK096-Bayes de Luna June 7, 2007 21:24 134 Self-assessment Answer to Case 7 Comment. This ECG belongs to a 60-year-old patient with a long-standing mi- tral and tricuspid valve. enlargement B Normal ECG variant; vertical heart with apparent levorotation C Normal ECG variant; horizontal heart D Normal ECG; heart with no rotation P1: OTE/SPH P2: OTE BLUK096-Bayes de Luna. OTE BLUK096-Bayes de Luna June 7, 2007 21:24 Self-assessment 127 A B –120° –90° –60° –30° +30° +60° +90° +120° +150° –150° + 180 ° – 0° I III ÂQRS first part +30°, +40° ÂQRS second part -1 40°, -1 50° II