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Risk factors for cardiovascular disease are commonly obtained in freshman medical students for the purpose of increasing interest and awareness in preventive cardiology. What would be a normal range of values for this select group? This paper describes the major cardiovascular risk factors for 3,811 male and female freshman medical students from eight U.S. medical schools that were obtained in a standardized fashion as part of the Preventive Cardiology Academic Award (PCAA) programs at these institutions. The distributions of height, weight, Quetelet index, systolic and diastolic blood pressures, total cholesterol, triglycerides, high-density lipoprotein cholesterol, and calculated low-density lipoprotein cholesterol are presented for male and female medical students stratified by race into white, black, Asian, and Hispanic groups. The sex and race distributions of cardiovascular risk factors such as previously diagnosed hypertension, diabetes mellitus, smoking, lack of regular exercise (three times a week or more), oral contraceptive use in women, and family history of coronary heart disease are presented. The cardiovascular risk of freshman medical students is compared to other epidemiologic studies of young adults. The use and limitations of these race- and sex-specific data on cardiovascular risk, including physiologic measurements, are discussed in the context of educational programs for medical students and house staff in preventive cardiology.

A scientific term is useful when it conveys precise meaning to serve as a reliable tool for communication. The term “shock” is widely used in many different contexts to convey many different meanings and has no universally accepted definition. From the clinical point of view, the term is most commonly used in referring to patients with acute systemic arterial hypotension accompanied by other signs and symptoms. The clinical manifestations vary widely but often include pallor, weakness, sweating, and rapid thready pulse. However, the essential characteristic is a markedly depressed systemic arterial pressure. Thus, the causes of shock must be sought among the factors which determine the pressure in the systemic arteries.

AQUATIC mammals and birds experience abrupt and profound cardiovascular changes during water immersion. In seals, for example, a diving bradycardia of one-tenth the normal rate without change in pressure has commonly been observed1,2. The evidence suggests that this is accompanied by a reduction in cardiac output and widespread vasoconstriction in skeletal muscle1,3, skin1 and kidneys4. Even in man, a relatively poor diver, the flow of blood in the limbs has been shown to decrease during breath-holding dives5. A single determination of cardiac output has been made in a seal during non-diving asphyxia6, but direct blood flow measurements are lacking.

1. 1. Ventral aortic blood velocity and pressure in free-swimming elasmobranchs were recorded with the Doppler ultrasonic telemetry blood flowmeter. 2. 2. Ejection time from the heart varied with the heart rate. Peak injection velocities ranged from 12–14 cm/sec in Horn sharks, 12–20 cm/sec in skates and 8–15 cm/sec in dogfish. Acceleration of the blood lasted from 120 msec in the Horn shark (T = 24°C) to 450 msec in the skates (T = 9°C). Deceleration of flows was slow in all species. Oscillations from bulbus cordis contraction and respiratory movements were superimposed on the basic wavefrom. Participation of the bulbar contraction in the cardiac sequence varied widely. 3. 3. Heart rates increased during short-lasting exercise. Peak velocity and flow were largeley unchanged. Peak velocity and flow frequently increased in the post-exercise period. 4. 4. The hemodynamic effects of atropine, acetylcholine and adrenaline are discussed in relation to the fact that the fish heart receives parasympathetic but not, apparently, sympathetic innervation.