THE HAeMODYNAMICS OF MITRAL STENOSIS BEFORE AND AFTER COMMISSUROTOMY

Abstract

Clinical changes following mitral valvotomy are sometimes difficult to evaluate. The need for an objective method in assessing the effectiveness of surgery is apparent, and the value of combined heart catheterization in appraising the hemodynamics of mitral stenosis has been reported (Goldberg et al., 1955 MATERIAL AND METHODS Sixteen patients, thirteen women and three men, were studied before and after mitral valvotomy. The diagnosis of pure mitral stenosis was confirmed by surgery in all patients. Mitral insufficiency was not produced in any case. Cardiac catheterization was repeated from twelve days to four months after operation.Combined heart catheterization was performed in the post-absorptive state with premedication consisting of seconal 120 mg. and demerol 50 mg. Right heart catheterization was done in the usual manner except that the patient was placed in the prone position. After the pulmonary venous capillary pressure was recorded, the catheter was positioned in the right or left pulmonary artery close to the hilus. A Cournand needle then was placed in the brachial artery. Left heart catheterization was performed by the Fisher modification (Kent et al., 1955) of the method originally described by Biork (1953). Our experiences in 450 cases of left heart catheterization are described elsewhere Musser et al., 1956). With the aid of fluoroscopy, a 6-inch, 18-gauge, thin-walled needle (Becton and Dickinson) was introduced into the left atrium via the eighth or ninth intercostal space 4 cm. from the midline. A polyethylene or nylon catheter was inserted through the needle. Continuous monitoring of the pressure was done on an oscilloscope or poly-oscillograph (Sanborn) as the catheter was advanced into the left ventricle. All manceuvring then was halted until the control cardiac rate, rhythm, and blood pressure were re-established. At this time, expired air was collected in a Tissot spirometer during a 3-min. period, at the middle of which samples were withdrawn from the pulmonary and brachial arteries simultaneously. Pressures were immediately recorded as the catheter was withdrawn from the left ventricle to the left atrium to determine the ventricular filling pressure gradient. In five patients with atrial fibrillation, a second needle was inserted into the left atrium and simultaneous recordings were made from the left ventricle and left atrium during estimation of the cardiac output.The cardiac output was calculated by the direct Fick method. Blood oxygen was determined according to the method of Van Slyke and Neill (1924). Respiratory analysis was done on the Pauling oxygen analyser. Pressures were measured by electromanometers and recorded on a poly-oscillograph (Sanborn).

The Course of the Total Pulmonary Resistance in Mitral Stenosis Following Mitral Valvotomy

“…Many excellent studies of the effects of mitral valvotomy on the hemodynamics of the pulmonary circulation have been reported Submitted for publication August 1, 1960. (1)(2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14).…”