Malfunction of the mitral valve prosthesis (Cutter-Smeloff). Clinical and hemodynamic observations in three cases

Prosthetic heart valves: a review

There are a number of difficulties inherent in the analysis of such a large and diverse quantity of data. In a substantial number of clinical trials, there is no significant effort made to evaluate prosthetic performance as a function of preoperative cardiac anatomy. Hemodynamics have not been systematically studied in relation to preexisting left ventricular size, shape, or configuration, mitral annular orientation, or left atrial size. Postoperative anticoagulation protocols vary from one institution to another and occasionally within study groups themselves. Less tangible variables such as alteration in surgical technique over time and differential familiarity of cardiovascular surgeons with the prostheses employed are chronic problems in any study of this sort. Perhaps the greatest variable in evaluating the postoperative performance of valvular prostheses over the past 20 yr is the radical improvement in techniques of intraoperative myocardial preservation. Notwithstanding, comparisons are possible within the confines of certain criteria. The caged ball value remains in use after 20 years of clinical experience. It has sustained the greatest number of modifications, probably because it has been the most extensively studied. Hemodynamics are adequate although its centrally obstructed design is responsible for increased turbulence, hemolysis, and neointimal proliferation, particularly in the aortic position. The device has been shown to be durable with virtually no reports of ball variance since the alteration of the silicone curing procedure in 1965. Thromboembolic rates are acceptable in the anticoagulated patient while prosthetic thrombosis is not a grave threat in the non-close clearance device. Incidence of endocarditis is not particularly different from that associated with all nonbioprosthetic valves, although there is a much greater published volume of clinical experience concerning recognition and treatment of late prosthetic valve endocarditis in patients with caged ball valves than there is for any other replacement device. Perhaps the most serious disadvantage to caged ball design is its size. Its large spatial requirements have led to anatomic complications in patients with small aortic roots, isolated mitral stenosis, left ventricular hypertrophy, and double valve replacement, among others. Nevertheless, this is still the valve of choice in some centers.(ABSTRACT TRUNCATED AT 400 WORDS)

Echo-phonocardiographic evaluation of obstruction of prosthetic mitral valve

Echo-phonocardiograms of 64 patients with multiple types of prosthetic mitral valves (PMV) were evaluated. Six patients demonstrated findings suggesting valve obstruction: four had surgical confirmation of prosthetic obstruction, one reduced cardiac output and pulmonary hypertension but no prosthetic dysfunction at surgery, and one is asymptomatic. Three of four patients with confirmed obstruction had variable second sound to opening click intervals (A2-MO) with interrupted disc opening; two had interrupted disc closure with split closing clicks and three of four had reduced diastolic closure rate. In 58 clinically well patients with PMV, cycle-to-cycle A2-MO varied little: 0-10 msec in sinus rhythm and 10-25 msec in atrial fibrillation. Diastolic closure rates of five different types of PMV were similar: 21.6 mm/sec, (range 14-49). No patient had interrupted opening, closing or multiple closing clicks. Thus, delayed PMV opening or closure, altered A2-MO interval and double closing clicks are highly useful in detecting patients with obstruction of a variety of mitral prostheses.

Ball variance in a Harken mitral prosthesis. Echocardiographic and phonocardiographic features

A case of ball variance in a caged-ball prosthetic valve is presented, illustrating the echocardiographic and phonocardiographic features. The swollen silicone ball was observed on echocardiographic studies to have diminished motion and to incompletely open within its cage. On phonocardiographic studies, the Q-S1 interval was prolonged, and no opening sound could be recorded. These noninvasive techniques may be helpful in predicting the need for replacement of prosthetic valves that have silicone rubber balls.

Echocardiographic and phonocardiographic confirmation of suspected caged mitral valve malfunction

Seven patients studied by echocardiography with and without simultaneous phonocardiography for suspected malfunction of a caged mitral valve prosthesis are presented. In case 1, with inaudible prosthetic clicks, thrombosis of the cage and immobility of the ball were suggested by echocardiographic studies and confirmed at surgery. In case 2, simultaneous echocardiographic and phonocardiographic studies demonstrated wide and variable intervals between the aortic second sound the the opening click and also "sticking" of the ball. In case 3 a thrombus prevented full motion of the ball to the apex of the cage, which was seen on the echocardiogram, while in case 4, with a thrombus within the ventricle and prosthesis, the prosthetic opening click was present intermittently and was associated with only subtle echocardiographic changes. In case 5, echocardiographic studies demonstrated abnormal rocking of the cage secondary to severe prosthetic dehiscence. In case 6, dul prosthetic clicks were to be secondary to a low cardiac-output state. In case 7, with multiple valve prostheses, simultaneous echocardiographic and phonocardiographic studies allowed identification of individual valve sounds and abnormal timing of valve opening. Based on these studies, we believe that echocardiography and simultaneous phonocardiography can yield very useful information in the evaluation of patients with suspected malfunction of a caged mitral valve prosthesis.

Diagnosis of prosthetic mitral valve malfunction with combined echo-phonocardiography

Fifty-three patients were studied with combined echo-phonocardiography or phonocardiography alone following prosthetic valve replacement. In sixteen of these patients, clinical deterioration developed, and all subsequently underwent cardiac catheterization and/or surgery. Two patients came to autopsy. Included in this group of sixteen patients were five with obstructed prosthesis, six with paravalvular regurgitation, and five with left ventricular dysfunction. Measurements were made of the time interval from the aortic valve closure sound to the peak opening of the mitral prosthesis determined echocardiographically or to the mitral prosthetic opening click (A2-MVO). Echocardiographic studies of left ventricular wall motion were also performed. The A2-MVO interval was significantly shortened (P less than 0.01) with prosthetic valve obstruction (.05 +/- .02 sec) and paravalvular regurgitation (.05 +/- .01 sec) compared with normally functioning prostheses (Starr-Edwards ball valves .10 +/- .02 sec, Lillehei-Kaster tilting disc prostheses .09 +/- .01 sec). Shortening of this interval was not specific for these conditions because it was sometimes shortened with left ventricular dysfunction. Echocardiographic studies of left ventricular wall motion were helpful in distinguishing among prosthetic valve obstruction, paravalvular regurgitation and left ventricular dysfunction. The combined echo-phonocardiographic technique was especially helpful in detecting malfunction of tilting disc prostheses, because the technique enables measurement of the A2-MVO interval in the absence of an audible opening click.

The phonocardiogram in a partially detached mitral (Starr-Edwards) prosthesis

Phonocardiographic evidence of extreme variability of the time interval between the aortic sound (A₂) and the opening click (OC) with intermittent absence of the OC of a partially detached mitral prosthesis of the Starr-Edwards type has not hitherto been reported. This case illustrates the diagnostic use of phonocardiography in a malfunctioning mitral Starr-Edwards prosthesis.

Current status of the Beall, Bjork-Shiley, Braunwald-Cutter, Lillehei-Kaster and Smeloff-Cutter cardiac valve prostheses

The Starr-Edwards ball valve prosthesis is generally the standard by which other cardiac valve substitutes are compared. This report reviews information pertaining to several prostheses--the Beall mitral valve and the Bjork-Shiley, Braunwald-Cutter, Lillehei-Kaster and Smeloff-Cutter aortic and mitral valves--considered by some to have specific advantages over the Starr-Edwards valves. Hospital and late mortality rates after valve replacement are comparable for the four aortic valve prostheses reviewed and depend more on patient selection than on the specific prosthesis utilized. Extensive clinical experience with the Bjork-Shiley aortic valve indicates that this prosthesis offers hemodynamic advantages over ball valve prostheses, especially in patients with a small aortic root. Clinical experience with the Lillehei-Kaster pivoting disc prosthesis has been less extensive, but this model provides theoretical hemodynamic advantages similar to those of the Bjork-Shiley aortic valve prosthesis. Problems associated with cloth wear and the unexpectedly slow rate, in man, of tissue ingrowth into the fabric of the Braunwald-Cutter aortic valve prosthesis have been discouraging, although this prosthesis has been associated with a very low thromboembolic rate in patients receiving anticoagulant therapy. The Smeloff-Cutter aortic prosthesis is hemodynamically similar to the Starr-Edwards prosthesis and has been proved to be a reliable and durable aortic valve substitute over the past several years. Mortality after mitral valve replacement is also largely influenced by factors other than prosthetic valve design. On the basis of postoperative data, the five mitral valve prostheses reviewed do not appear to have substantial hemodynamic differences. For patients with a small left ventricular cavity the low profile prostheses, such as the Beall, Bjork-Shiley and Lillehei-Kaster, may be advantageous. Most available evidence indicates that patients receiving aortic or mitral valve prostheses should be given anticoagulant therapy postoperatively.

Delayed opening of Beall mitral prosthetic valve detected by echocardiography

A 47-year-old woman in normal sinus rhythm developed frequent pulse deficits, immediately following mitral valve replacement with a Beall disc prosthesis. Emergency bedside simultaneous tracing of echocardiogram, phonocardiogram and arterial pulse revealed a delayed opening of the disc with various timing intervals in diastole, and suggested some form of interference with normal disc motion. An interfering papillary muscle remnant was later confirmed and corrected by reoperation.