24
individuals. Left axis deviation, and onlyof modthe younger unexposed group, three in the older
individuals examined in the unexposed group
>70 years of age for comparison, any assumption
group. Theelectrical position of the heart ina
individuals by their exposure to fallout radiation is
erate degree, was presentin six individuals, two in
unexposed group, and onein the older exposed
great majority of both the unexposed and exposed
subjects wasvertical. In 22 subjects it was intermediate and in 9 (all unexposed) it was moderately horizontal. Rotation of the heart electrically
in the combined groups was clockwise in 25 sub-
jects and counterclockwise in 36, with about equal
distribution between the exposed and unexposed
groups.
py
years of age in the exposed group, and then toa
degree compatible with age. Since there were no
4. RSTandT Waves. Abnormal variations were
carefully noted for indications of coronary or myocardial insufficiency and/or myocardial disease or
damage. Deviations of the RST segmentfrom the
isoelectric line were found to be minimal; they oc. curred in only five of the 84 unexposed subjects
and in only one of the 38 exposed subjects. T wave
abnormalities were of appreciable degree in only a
few instancesin the older group. The abnormalities
werechiefly in lower T waves and wererelated to
hypertensive disease. T wave changes were most
marked in a 51-year-old male ( #80) of the exposed group, who had arteriosclerotic heartdis-
ease and auricular fibrillation. Marked RST and
T wave changes were noted in an 81-year-old
male (#46) of the exposed group, who had
marked hypertensive and arteriosclerotic cardiovascular disease, and had prolonged auriculoventricular conduction time as noted above.
Amongthe unexposed population there wasevidence of myocardial insufficiency according to
RST and T wave changesin a 51-year-old male
(+947), a 64-year-old female (#861), a 55-yearold male ( #993), a 64-year-old female (#858),
and a 64-year-old male (4884); the last had
changessufficient to indicate a healed anterior
septal cardiac infarct.
Other Cardiovascular Observations
1. Peripheral Vascular Findings. Clinicalestimation was madeof the degree of arterial changes
in the peripheralvessels (radial, brachial, and dor-
salts pedis). The degree of abnormality was graded
by 0 to 4+ sclerosis (see section on agingstudies).
Arteriosclerosis was seen chiefly in subjects >>50
year of age in both exposed and unexposed groups.
It was not marked exceptin four individuals >>70
that the arteriosclerosis was increased in these four
unwarranted. Otherwise the presence and the
amountof arteriosclerosis was fairly well distributed between both populations, as can be seen in
Table 14. It was not observed in a degreepre-
mature or advancedfor the given age.
2. Arterial Blood Pressures.
Blood pressures
greater than 140 systolic and 90 diastolic were
considered abnormal. Onthis basis in the exposed
group none of the 24 subjects <50 of age and seven
of the 16 subjects >50 had hypertension, but
mostly of mild degree. There were 17 cases of hy-
pertension in the unexposed group, 2 in those <(50
years of age and 15 in those >50. Thediastolic
blood pressure showed only infrequent increase
above the level of 90 mm; as would be expected,
this occurred chiefly in the older group. The over-
all incidence of hypertension for the total population examined was 9.2%.
3. Oscillometry Readings. Observations were
taken on the legs at the mid-calf. In almostail
subjects the pulsation was sufficient to indicate
normal blood flow. Aithough the readings were
lower in the Marshallese than might be expected
in Caucasians, it appeared that peripheral vascuTable 16
Ophthalmological Findings (% Incidence)
Pterygium
Pinguecula
Corneal pigment
Corneal scars
Arcussenilis
Phthisis bulbi
Nystagmus
Strabismus
Argyll-Robertson pupil
Cataracts
Aphakia
Vitreous opacities
Retinalarteriosclerosis
Chorioretinal scars
Macular degeneration
Driisen
Congenital anomalies
Exposed
Unexposed
23.0
24.0
12.0
9.0
38.0
1.3
1.3
8.3
1.3
19.0
1.3
4.1
11.0
1.3
0.0
2.6
3.9
21.0
22.0
2.6
3.4
26.0
0.0
0.7
0,7
0.0
10.3
1.3
0.0
12.3
0.7
0.0
0.0
0.0
pron nq
axis deviation was normalor to the right in most