The sudden death of young people because of heart pathology is one of the most difficult problems in forensic medicine if the autopsy reveals no changes.
The small vessel disease could only be diagnosed at microscopical examination of heart specimens taken from a few definite sites.
The pathology of small vessels is described with various cardiac conditions including diabetes mellitus, amyloidosis, connective tissue disease , and hypertrophic cardiomyopathy . Alterations in small myocardial arteries are described for cases having a toxic oil syndrome caused by poisonings with rapeseed oil adulterated with aniline . Its clinical manifestations include pulmonary hypertension, right venrticular hypertrophy, extensive vascular and neutral lesions, and scleroderma-like disease. The similar pathology of myocardial, femoral and carotid arteries are described in cases of the eosinophilia-myalgia syndrome .
However, the etiology of the small artery pathology could not be established in all the cases. This kind of the pathology is called small vessel disease, or fibromuscular displasia, or medial hyperplasia obliteranse. Similar changes are described in renal  and carotid arteries [6, 7, 8] because they are connected with typical clinical symptoms.
The majority of researchers did not refer to the small vessel pathology because this kind of pathology occurs but very seldom. However, one of them, namely, G. Baroldi  described its occurrence in 52 p.c. of sudden deaths and in 78 p.c. of lethal traumas.
The correct recognition of this disease is based on the revelation hyperplasia and hypertrophy of smooth muscle cells with longitudinal and oblique bundle formation, dramatic thickening of the media and fibrous replacement with lumen reduction. Neither aneurysms, nor inflammatory reactions or abnormal depositions have been observed. This process has shown a preferential location in anterior papillary muscles, columnae carnea, and superior interventricular septum.
As an example, we are going to describe one case history out of our experience.
A 26-year old officer came to work early in the morning. A few minutes later he complained of retrosternal disturbance, fell down, became pale and died. All the previous regular medical examinations had not revealed any pathology.
The autopsy of the young man, 195 cm tall, registered only the symptoms of a sudden death. The heart (its size, mass, cavities, walls, and coronary arteries) were standard. Toxicological examination did not reveal anything either.
The specimens of the myocardium were extracted sporadically, even though from all the major parts. All of them were marked.
The histological slices were coloured with hematoxylin and eosine by Van Gison, with fuxelinum and orange-red-blue by Zebrino (ORB).
The interventricular septum ends near the connecting system node in slices of the columnae carnea. We have found out some thickness of the vessel wall in several small arteries caused by hyperplasia and hypertrophy of the smooth muscles cells. Several parts of the artery muscle walls were marked with fibrosis. There was a formation of the subendotilial-perivascular connections (Fig. 1). Elastic fibers of the vessel walls were fragmented. The lumen was contracted (Fig. 2).
This example points to the importance of the correct extraction of specimens from the heart.
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