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CHAPTER 28
FIG. I93C. 1.31 p.m. Lead I. Every third conducted beat is followed by a ventricular
extra-systole. In contrast with Fig. 2 the P-R interval is normal.
FIG. i93d. 1.38 p.m. Lead I. Bradycardia, rate 54 per minute with normal sinus rhythm
during uterine contractions with moderate rise of blood pressure.
FIG. 1936. 1.52 p.m. Height of hypertension. Lead I. P-waves marked by arrows.
The first P-R interval is 0-34 seconds, the next two are 0-4 seconds, the fourth P-wave is
not conducted and the ensuing interval is terminated by an A-V escape beat, the fifth
P-wave is hidden in the ventricular complex, thus the first part of the tracing shows 2nd
degree A-V block 4:3. The sixth and seventh P-waves are conducted (P-R interval
0-4 seconds), but the eighth is not; the interval is again terminated by an A-V escape beat,
the R-wave of which is deformed by the next P-wave (2nd degree A-V block 3:2).
Following this, there is a ventricular extra-systole the S-T segment of which is deformed
by the next P-wave. This extra-systole differs in shape and direction from those seen in
Figs. 1933 and 1930. From Frankel, Guttmann and Paeslack (1965)
Paraplegia,
3, 147.
FIG. I93f. 1.52 p.m. Height of hypertension. Lead I. Two ventricular extra-systoles of
different shape and size; the third and fifth arrows show P-waves distorting the S-T
segment of the extra-systoles.
FIG. I93g. 1.55 p.m. During delivery. Lead I. No P-waves seen. Every 2nd supra-
ventricular beat is followed by a ventricular extra-systole. The extra-systoles are again
similar to those seen in Figs. 1933 and I93C.
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FIG. i93h. 1.55 p.m. During delivery. Lead I. No P-waves seen. Each supra-ventricular
beat is followed by a ventricular extra-systole ('coupling' or 'bigeminus').
FIG. i93i. 1.59 p.m. During delivery of placenta. Lead I. Sinus rhythm, two ventricular
extra-systoles.
