MEDICINE HURST VENTRICULAR ELECTROCARDIOGRAPHY - Part 10 ppsx

... minute or less). • Premature atrial, junctional, or ventricular depolarizations. • First-degree atrioventricular block, second-degree atrioventricular block, and Mobitz type I block. • Increased ... 0.0 4- second QRS vector is directed about -5 5° to the left and 40° posteriorly. The mean T vector is directed 50° inferiorly and about 30° anteriorly. The ventricular gradient is b...

Ngày tải lên: 14/08/2014, 07:20

... of the interventricular septum. The left bundle divides to form two branches, although Tawara called it tripartite. The major divisions are the anterior-superior and the posterior-inferior divisions. ... Figure 4 .10 Tawara's view of the left bundle branch. This diagram is taken from the monograph by Tawara (1906), [10] which established and elucidated the significance of the atr...

Ngày tải lên: 14/08/2014, 07:20

... accessory pathway. The Wolff-Parkinson-White syndrome. The Wolff-Parkinson-White syndrome consists of the electrocardiographic abnormalities of ventricular pre-excitation, including a short ... vector is -7 0°-to the left and 10 to 15° posteriorly. There are no Q waves in leads I and V6, and there is no R wave in lead V1. The mean terminal 0.04-second QRS vector is directed -1 1...

Ngày tải lên: 14/08/2014, 07:20

... VENTRICULAR ELECTROCARDIOGRAPHY © 1998 J. Willis Hurst, MD 10 Figures 1.3A A.Willem Einthoven (186 0-1 927). This Dutch physiologist ... important and exciting subject of ventricular electrocardiography. There has been a decline in the interest of physicians in learning and teaching ventricular electrocardiography....

Ngày tải lên: 14/08/2014, 07:20

... Electrocardiography. New York: McGraw- Hill, 1957, p. 49.) The initial and terminal mean instantaneous QRS vectors. The frontal plane directions of the 0.0 1-, 0.0 2-, 0.0 4-, 0.0 6-, and 0.08-second ... Chapter 6). The ventricular gradient is directed away from the area of the heart where repolarization is delayed. In general, normal T waves are subject to more hour-to-hour or...

Ngày tải lên: 14/08/2014, 07:20

... frontal plane projections of the normal 0.0 1-, 0.0 2-, 0.0 4-, 0.0 6-, and 0.08-second QRS vectors are shown in Figure 5.9. Normally, the initial 0.0 1- to 0.02-second QRS vectors are anterior to the ... cases the mean terminal 0.04-second QRS vector may be directed as far as -1 00° to the left because there is associated left anterior- superior division block) (Fig. 6.10C);...

Ngày tải lên: 14/08/2014, 07:20

... abnormality. Note that the ventricular gradient (VG) is abnormal. D. Uncomplicated LBBB. Note the normal ventricular gradient (VG). This is a secondary T wave abnormality. Note that the ventricular gradient ... any type of cardiac dysrhythmia, including ventricular dysrhythmias, atrial dysrhythmias, and varying degrees of atrioventricular block. Except for ventricular dysrhythmia...

Ngày tải lên: 14/08/2014, 07:20

... complex is 0 .10 second, whereas in patients with left ventricular hypertrophy, it is often less than 0 .10 second. The mean QRS vector is directed beyond -3 0° to the left when left anterior-superior ... deflections are absent in left ventricular conduction delay. Left ventricular hypertrophy may, however, be associated with left ventricular conduction delay. • In left anter...

Ngày tải lên: 14/08/2014, 07:20

... abnormal. The mean QRS vector is directed at -1 00° superiorly, and about 60° posteriorly. The mean initial 0.04-second QRS vector is directed at -8 5° superiorly and about 30° anteriorly, away ... electrocardiographic abnormalities. Figure 11.10A These electrocardiograms, showing the development of a right ventricular infarction, were recorded from a 51-year-old man. He had an...

Ngày tải lên: 14/08/2014, 07:20

... 0.01-second QRS vector. Note that it is posterior to the 0.02-second vector. D. The spatial orientation of the mean initial 0.02-second QRS vector; note that it is anterior to the 0.01-second ... The electrocardiogram of a 54-year-old patient made shortly after pulmonary embolism. The direction of the mean terminal 0.04-second QRS vector indicates right ventricular conduction delay, ......

Ngày tải lên: 14/08/2014, 07:20