. Physical diagnosis . iswrong. For physical diagnosis, then, heart disease means either deformedvalves or weakened walls. I include here, under the results of weak-ened walls, all the disorders of conduction and rhythm described onpages 244 to 250. Whatever else may exist, we are none the wiserfor it unless the autopsy enlightens us. In this chapter I shall confine myself to the discussion of valvularlesions and their results. Valvular lesions are of two types: (a) Those which produce partial obstruction of a valve orifice orprevent its opening fully (stenosis). 191 192 PHYSICAL DIAGNOSIS (6)
. Physical diagnosis . iswrong. For physical diagnosis, then, heart disease means either deformedvalves or weakened walls. I include here, under the results of weak-ened walls, all the disorders of conduction and rhythm described onpages 244 to 250. Whatever else may exist, we are none the wiserfor it unless the autopsy enlightens us. In this chapter I shall confine myself to the discussion of valvularlesions and their results. Valvular lesions are of two types: (a) Those which produce partial obstruction of a valve orifice orprevent its opening fully (stenosis). 191 192 PHYSICAL DIAGNOSIS (6) Those which produce leakage through a valve orifice or preventits closing effectively {regurgitation, insufficiency, incompetency). Stenosis results always from the stiffening, thickening, and con-traction of a valve. Regurgitation, on the other hand, may be the result either of— (a) Deformity of a valve, or (6) Weakening of the heart muscle. Valvals semilunarisBiaiStrn a. pfhrnsmalis , ,„,„:, „„„.., J. J. Fig. 139.—The Base of the Contracted Heart Showing Sphincteric Action of the Mus-cular Fibres Surrounding the Mitral and Tricuspid Valves. The outer dotted line is theoutline of the relaxed heart. The inner dotted circles show the size of the mitral andtricuspid valves during diastole, a, Outline of the heart when relaxed; b, outline of therelaxed tricuspid valve; c, outline of the mitral orifice during diastole. (After Spalteholz.) The mitral and tricuspid orifices are closed not simply by theshutting of their valves, but also in part by the sphincter-like actionof the circular fibres of the heart wall (see Fig. 139) and the contractionof the papillary muscles (Fig. 140). In birds the tricuspid orifice has no valve and is closed wholly bythe muscular sphincter of the heart wall. In conditions of very acute cardiac failure, such as may occurafter a hard run, the papillary muscles are in all probability relaxed, VALVULAR LESIONS 193 so that the valve-flaps swing
Size: 1769px × 1412px
Photo credit: © Reading Room 2020 / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1910, booksubjectdiagnos, bookyear1912
