Constitutional treatment consists in taking measures to reduce the arterial tension and to diminish the force of the heart’s action.  The patient must be kept in bed.  A dry and non-stimulating diet is indicated, the quantity being gradually reduced till it is just sufficient to maintain nutrition.  Saline purges are employed to reduce the vascular tension.  The benefit derived from potassium iodide administered in full doses, as first recommended by George W. Balfour, probably depends on its depressing action on the heart and its therapeutic benefit in syphilis.  Pain or restlessness may call for the use of opiates, of which heroin is the most efficient.

Local Treatment.—­When constitutional treatment fails, local measures must be adopted, and many methods are available.

#Endo-aneurysmorrhaphy.#—­The operation devised by Rudolf Matas in 1888 aims at closing the opening between the sac and its feeding artery, and in addition, folding the wall of the sac in such a way as to leave no vacant space.  If there is marked disease of the vessel, Matas’ operation is not possible and recourse is then had to ligation of the artery just above the sac.

Extirpation of the Sac—­The Old Operation.—­The procedure which goes by this name consists in exposing the aneurysm, incising the sac, clearing out the clots, and ligating the artery above and below the sac.  This method is suitable to sacculated aneurysm of the limbs, so long as they are circumscribed and free from complications.  It has been successfully practised also in aneurysm of the subclavian, carotid, and external iliac arteries.  It is not applicable to cases in which there is such a degree of atheroma as would interfere with the successful ligation of the artery.  The continuity of the artery may be restored by grafting into the gap left after excision of the sac a segment of the great saphena vein.

Ligation of the Artery.—­The object of tying the artery is to diminish or to arrest the flow of blood through the aneurysm so that the blood coagulates both in the sac and in the feeding artery.  The ligature may be applied on the cardiac side of the aneurysm—­proximal ligation, or to the artery beyond—­distal ligation.

Proximal Ligation.—­The ligature may be applied immediately above the sac (Anel, 1710) or at a distance above (John Hunter, 1785).  The Hunterian operation ensures that the ligature is applied to a part of the artery that is presumably healthy and where relations are undisturbed by the proximity of the sac; the best example is the ligation of the superficial femoral artery in Scarpa’s triangle or in Hunter’s canal for popliteal aneurysm; it is on record that Syme performed this operation with cure of the aneurysm on thirty-nine occasions.