Coronary sclerosis

Sorgo G. 1976. [Trichloroethylene, carbon tetrachloride, and gasoline intoxication as etiological factors in the development of arterio- and coronary sclerosis.] Arch Toxicol 35 295-318. (German)... 

In addition to coronary sclerosis, evidence is accumulating that high Lp(a) levels may be important in the development of cerebrovascular and peripheral arterial disease, as well (J6, T8, U2). Lp(a) levels not only correlated well with clinical endpoints such as transient ischemic attack and cerebral infarction, but also were associated with the extent and severity of carotid atherosclerosis, as assessed by bidirectional Doppler ultrasound (K23, M33, Z2). 

Thus, the nitrates enable myocardial flow resistance to be reduced even in the presence of coronary sclerosis with angina pectoris. In angina due to coronary spasm, arterial dilation overcomes the vasospasm and restores myocardial perfusion to normal. O2 demand falls because of the ensuing decrease in the two variables that determine systolic wall tension (afterload) ventricular filling volume and aortic blood pressure. 

The choice between calcium antagonists must take into account the differential effect of nifedipine versus verapamil or diltiazem on cardiac performance (see above). When p-blockers are given, the potential consequences of reducing cardiac contractility (withdrawal of sympathetic drive) must be kept in mind. Since vasodilating P2-receptors are blocked, an increased risk of vasospasm cannot be ruled out Therefore, monotherapy with p-blockers is recommended only in angina due to coronary sclerosis, but not in variant angina. 

Angina pectoris Coronary sclerosis Coronary spasm... 

Owing to their large caliber, the proximal coronary segments do not normally contribute significantly to flow resistance. However, in coronary sclerosis or spasm, pathological obstruction of flow occurs here. Whereas the more common coronary sclerosis cannot be overcome pharmacologically, the less common coronary spasm can be relieved by appropriate vasodilators (nitrates, nifedipine). 

The caliber of arteriolar resistance vessels controls blood flow through the coronary bed. Arteriolar caliber is determined by myocardial 02 tension and local concentrations of metabolic products, and is automatically adjusted to the required blood flow (B, healthy subject). This metabolic autoregulation explains why anginal attacks in coronary sclerosis occur only during exercise (B, patient). At rest, the pathologically elevated flow resistance is... 

Evidence for correlations between the two diseases should be sought for by comparing the data on the diseased subjects with the corresponding normal ones, i.e. subjects with coronary sclerosis compared with healthy persons of the same sex and age, and patients with a toxemia of pregnancy with women with uncomplicated pregnancy of comparable duration. 

Many papers have been published in recent years on the influence of diet upon atherosclerosis and especially coronary sclerosis (Felch et al., 1958). Data on the relation between diet and toxemia of pregnancy are not as numerous and many are of somewhat older date. 

A suddenly improved supply of foods such as occurred at the end of the war in Western Europe resulted in an inunediate sharp increase of the toxemia incidence. The incidence of coronary mortality rose likewise, but not so sharply. This difference in rate of increase is not as contradictory as it might seem, since it might well be related to the acute coiu of toxemia of pregnancy in comparison with the always more chronic progress of coronary sclerosis. 

In mild cases of toxemia, as well as in coronary sclerosis, therapy with the so-called rice-water-fruit diet may owe part of its good effects to better supply of magnesiiun and potassium, while the sodium content is low. This may be as important as the low fat and calorie content of the diet. 

A comparison of these two diseases in respect to the clinical symptoms may seem impossible at first sight. However, a few details of the syndromes in both diseases may be mentioned. The most evident symptom of toxemia of pregnancy, the elevated blood pressure, is not seen in coronary sclerosis or, at least, not to such an extent. However, according to Brown et oi. (1957), the blood pressure in coronary disease, before infarction has occurred, is slightly raised on an average, compared with that in healthy men of the same age. After the recovery from the acute phase of an infarction, the blood pressure becomes fixed at a lower level than that in the healthy controls. A regulating system to supply the tissues with blood as well as possible is certainly present and substances released from the ischemic and injured tissues must play a role. 

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