tailieunhanh - Basic Electrocardiography Normal and abnormal ECG patterns - Part 8

Để xác nhận xem bạn đã hiểu rõ những cuốn sách và kiểm tra điện tâm đồ của bạn kỹ năng diễn giải, chúng tôi sẽ tiến hành bằng cách tiến hành một thử nghiệm nhiều lựa chọn. Trong thử nghiệm này, bạn sẽ được yêu cầu cung cấp một câu trả lời chính xác dựa trên trình bày ghi điện tâm đồ. | 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-Talternans Hyperacute phase of severe myocardial ischaemia Congenital long QT syndrome Electrolytic imbalance Figure 107 A Typical examples of electrical alternans. A Alternans of QRS in a patient with pericardial tamponade. B ST-QT altemans in Prinzmetal angina. C Repolarisation altemans in important electrolyte imbalance. 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. Case 1 A young asthenic man with no apparent heart disease. The figure shows an ECG tracing in VI 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 Brugada s syndrome . D False image of right bundle branch block 121 122 Self-assessment Answer to Case 1 Comment. A Normal ECG recording except VI where final R wave is quite prominent and final r in V2 and RS morphology in V3 are present. Due to this morphology in VI it is necessary to rule out RBBB. The evidence that the p wave in VI is completely negative made US think that VI lead is placed Ingherfsrcondrightmtercoshs1 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 VI when the lead was located correctly in fourth right intercostal space C . We can conclude that in this case