This study attempts to bring into focus certain details which have not been described adequately in textbooks of anatomy. This information is now of considerable significance because of its role in the genesis and surgical treatment of mitral stenosis. Variations in the size and shape of the mitral valve are described, with particular reference to the fact that valve commissures, or junctional zones between the leaflets, occur in the normal valve. Measurements of commissures, chordae tendineae and valve leaflets are presented, with a discussion of the significance of some of these measurements.
Mural Thrombosis and Arterial Embolism in Mitral Stenosis
A clinicopathologic study of 51 cases of mitral stenosis with intracardiac mural thrombi is presented with particular reference to the locations of these thrombi and their relationship to the associated thromboembolic phenomena. In 27 cases the thrombi were present only in the left side of the heart, in 15 cases they were in both sides of the heart, and in 9 cases they were present only in the right atrium. Of 42 cases in which thrombi were located in the left side of the heart, in 20 the thrombi were limited to the left auricular appendage. In the remaining 22 cases in this group the thrombi in the left side of the heart were situated on the main atrial wall, in the auricular appendage and on the main atrial wall together, or in the left ventricle. Systemic arterial emboli occurred frequently regardless of the particular site in the left side of the heart at which the thrombus formed. Of 24 cases in which thrombi were situated in the right side of the heart, in 20 the thrombi were restricted to the right auricular appendage.
Only 5 reports of cases of renal arteriovenous fistula appeared before or in 1953. Subsequently, 7 isolated reports brought the total to 12, and the 3 that we are reporting make 15. In reviewing the subject, the classification, incidence, causation, clinical features, diagnostic procedures, and pathophysiologic features were considered. Good evidence supports the thesis that in cases of congenital arteriovenous fistula an eroding renal arterial aneurysm is etiologic. Outstanding clinical features were hypertension (to group 4) and myocardial insufficiency; these contrast markedly with features of the usual peripheral arteriovenous fistula. Dramatic relief of heart failure and lowered reserve followed corrective operation in every case in which these features were recorded; relief of hypertension followed corrective operation in 11 of 12 cases in which this feature was mentioned. A loud, diffuse, continuous bruit invariably was present. Preoperative and postoperative catheterization and indicator-dilution studies, angiograms and aortograms are diagnostic measures emphasized in our 3 cases. Arterialization of blood in the vena cava, greatly increased cardiac output, and markedly shortened recirculation times of the dye were found. Excretory urograms were abnormal in 11 of the 12 cases in which they were made. The mechanism producing hypertension appears related to loss of pressure, decrease in flow, and loss of pulsatile character in the renal artery distal to the fistula, giving a Goldblatt-kidney type of end result. A vicious cycle of increasing hypertension followed by increasing flow through the shunt makes heart failure inevitable. Since 10 of the 15 cases were reported in the last 4 years, indicating that the lesion is commoner than previously supposed, we advise auscultation over the renal regions in patients with cardiac enlargement or failure of unknown causation, unexplained deformities in urograms, and renal tumors.
Knowledge of the structural changes in the commissures, cusps, and chordae tendineae is important to the understanding of the pathologic physiology of mitral stenosis and its surgical correction. Study of 70 hearts with mitral stenosis disclosed that a frequent cause of the obstruction was commissural fusion or shortening of the chordae tendineae or both. In a small percentage of hearts, mitral stenosis appeared to result principally from rigidity of the valvular leaflets. Measurements of the various components of the mitral valve in normal hearts have been given in a previous paper. In this communication, comparable measurements for these structures in 50 hearts with mitral stenosis are presented.
Albuminuria may be an integral part of the picture of congestive heart failure. Of 161 patients in whom the histologic renal findings were considered to be either normal or to be of such a nature as not to be responsible in themselves for albuminuria, and in whom clinically obvious causes for albuminuria had been eliminated, 141, or 88 per cent, had albuminuria. The incidence of albuminuria was about equal among the various types of heart disease when heart failure existed. A trend existed for the grade of albuminuria to parallel the grade of heart failure. Based on a study of 21 patients, there seemed to be a correlation between the grade of albuminuria and the group of hypertension, according to funduscopic examination. No correlation was found between the grade of albuminuria on one hand and the systolic or diastolic values for blood pressure, the known duration of elevated blood pressure, the grades of hematuria or the values for blood urea on the other hand. Among the 161 patients with heart failure in our group 1 (kidneys either normal or containing lesions not judged to be causes for albuminuria), there was no predominant renal lesion associated with any one cardiac lesion.