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HANDBOOK OK PHYSIOLOGY 



CIRCULATION II 



as tliose primarily oriented best from the standpoint 

 of discussion of mechanisms in peripheral vascular 

 disease. Particular emphasis is placed on vasocon- 

 strictor and vasodilator disease states. 



MECHANISMS IN PERIPHERAL VASCULAR DISEASE 



I asoconstrictoi Disease Syndromes 



Raynaud's syndrome or phenomenon. This syndrome 

 or phenomenon had been known for years before the 

 time of Raynaud. Ragnetta, Huguier, Virchow, 

 Zambaco and others commented on the syndrome, 

 but Raynaud's thesis published in 1862 (84) first 

 brought wide attention to the syndrome as a distinct 

 entity. Since that time Lewis' work has been out- 

 standing (46, 48, 49). 



For purposes of classification and diagnosis one 

 may refer to a) primary (idiopathic) Raynaud's 

 syndrome or phenomenon, and b) secondary Ray- 

 naud's syndrome or phenomenon. When Raynaud's 

 svndrome occurs as a primary manifestation and 

 without any obvious underlying or predisposing 

 cause, it is termed "primary." When the syndrome 

 occurs as a result of, or in association with, some 

 other disease which is known to be of significance in 

 predisposition to or production of the syndrome, it is 

 termed "secondary." Obviously, the classification 

 of the secondary type is somewhat crude, since it is 

 based upon empiric observation of an association of 

 the syndrome with some other disease process with 

 .1 frequency not expected in otherwise normal people. 

 Certainly the primary syndrome must be secondary 

 to its cause. Nevertheless, for diagnostic, prognostic, 

 and therapeutic reasons, this classification is helpful. 

 Raynaud's disease is the term applied when the 

 typical phenomena have been present for 2 years 

 without detection of any obvious cause. Although 

 this terminology is arbitrary, it is clinically valid 

 since most diseases in which Raynaud's syndrome is 

 a secondary manifestation are usually diagnosed 

 within a 2-year period (22). 



Raynaud's syndrome characteristically consists 

 of transient episodes of digital pallor, cyanosis, and 

 erythema. The typical progression would be from 

 pallor, to cyanosis, to erythema, but this is not always 

 true. Erythema is not invariably noted and its 

 presence is not a requirement for diagnosis. Although 

 a pale blue-gray reaction usually precedes the stage 

 of pallor (or cyanosis when pallor is absent), it 

 frequently escapes notice. In order to diagnose 



Raynaud's syndrome confidently there should be at 

 least intermittent attacks or crises of either digital 

 pallor (syncope) or digital cyanosis. Both may be 

 present and either or both may be associated with 

 subsequent erythema. 



Primary Raynaud's phenomenon and Raynaud's disease. 

 Raynaud's disease usually, but not invariably, appears 

 before the age of forty and is much more frequent in 

 lemales. Typically the vasomotor episodes are precipi- 

 tated by exposure to cold and occasionally by emo- 

 tional stress. In diagnosis, blanching can often be 

 produced by submerging the hands or feet in water 

 at an optimum temperature (49) of approximately 

 15 C (range, 12 to 18 C) for 10 to 15 min, but failure 

 to produce the characteristic manifestations of the 

 attack does not exclude the diagnosis (1, 49, 60). 

 However, failure to produce blanching by this 

 means plus additional preliminary or simultaneous 

 general body cooling (e.g., a cold shower) is reliable 

 evidence that Raynaud's syndrome does not exist. 

 Water of icy coldness tends to produce a red reaction 

 even in patients with Raynaud's syndrome. It is 

 important to differentiate Raynaud's phenomenon 

 from cold allergy which produces an erythematous 

 pruritic edema but not true blanching (60). 



The vascular reactions and color changes of Ray- 

 naud's syndrome tend to occur segmentally and 

 bilaterally in the digits, generally terminating at the 

 interphalangeal or metacarpophalangeal articula- 

 tions. Although there is a distinct tendency for the 

 syndrome to occur bilaterally and symmetrically 

 some asymmetry in degree of involvement of either 

 hand is not uncommon. Involvement of an extremity 

 characteristically does not extend proximal to the 

 metacarpo(tarso)phalangeal joint. The feet may be 

 involved, but the hands are involved much more 

 frequently. Involvement of other parts of the body 

 is occasionally seen, especially such acral parts as 

 the ear lobes, cheeks, tongue, and the tip of the nose. 



The localization of the vascular lesions to the 

 hands and feet is of interest. When only a single 

 phalanx is involved, it is the distal one; when two 

 phalanges are involved, they are the distal two. All 

 three phalanges of a digit or several digits of either 

 hand may be involved. In a single digit the direction 

 of progression of changes during an attack is from 

 distal to proximal. The second or fifth or both digits 

 are involved most often. When only the very tip of 

 the distal phalanx is involved, this suggests changes 

 in vessels smaller than the digital arteries. Localiza- 

 tion of Raynaud's reaction, which rarely occurs in 

 parts of the body other than the digits, is apparently 



