The electrocardiogram in experimental chagas disease

567

SELECTFD A ABSTRACTS b

The use of fetal electrocardiography and fetal stethographg for routine and eontiultation purposes is recommended because of the simple procedure involved and the ease with which tracings can be interpreted. A case of breech presentation with positive tracing in Lead I, and variations in maternal and fetal rate is discussed. AUTHORS.

Hoff, H. E., Nahum, L. H., and Kaufman, W.: The Nature of the Electrocardiogram. Am. J. Physiol. 134: 390, 1941. Lead I records the algebraic posterior dextrocardiogram. Lead III records the algebraic the posterior levocardiogram.

summation

of the

summation

anterior

of Leads I and III

levocardiogram

of the anterior

and

dext,rocardiogram

the and

AUTHORS.

Nahum, L. II., Hoff, H. E., and Kaufman, W.: Formation Electrocardiogram. Am. J. Physiol. 134: 384, 1941. The of the

R complex of the electrocardiogram initial portions of the dextroand

results from levocardiograms.

of the R Complex of the the

algebraic

summation

When the R complex is upright, its initial deflection is the upstroke of the dextrocardiogram, while the downstroke is produced by the onset and development of the levocardiogram. When the R complex is directed downward, the downstroke is the initial portion of the levocardiogram, while the upstroke is produced by the onset and development of the dextrocardiogram. The amplitude of the R complex varies with the interval separating onset of the dextroand levocardiograms. The maximum amplitude is limited by the amplitude of the component dextroor levocardiograms. AUTHORS.

Taquini, Rev.

Alberto argent.

C.: de cardiol.

The Electrocardiogram 8: 115,

Inoculation of puppies with cardiographic alterations-arrhythmias complexes, evidenre of myocardial

in Experimental

Chagas Disease.

1941.

Tripunozomn and damage.

C~~zii changes

is followed by marked electroin auricular and ventricular AFTHOR.

Steele, J. : Evidence for General Distribution of Peripheral tion of the Aorta: Report of Three Cases. J. Clin.

Resistance in CoarctaInvestigation

20:

473,

1941. Review of the knowledge of levels of arterial pressure in 317 cases of coaretation of the aorta makes untenable the assumption that inrrease in peripheral resistance is situated in the upper half of the body only. In two of three cases of coarctation of the aorta, diastolic pressure has been shown by intra-arterial measurement to be elevated above 100 mm. Hg in the femoral as well as in the radial arteries. This is interpreted as evidence of general increase in arteriolar tone throughout the body. In so far as the distribution of peripheral arteriolar resistance is concerned, arterial hypertension in coarctation of the aorta does not differ from the common forms of arterial hypertension. AUTHOR.