Tricuspid Valve Prosthesis Research Articles

Doppler hemodynamic profiles of 82 clinically and echocardiographically normal tricuspid valve prostheses.

Normal Doppler hemodynamics for tricuspid prostheses have not been well characterized in a large group of patients. Therefore, we analyzed comprehensive Doppler echocardiographic examinations of 82 patients with tricuspid prostheses that were normal by clinical and two-dimensional echocardiographic examinations to establish the normal hemodynamics of various types and sizes of tricuspid prostheses. The earliest complete postoperative echocardiographic study from each patient was chosen for analysis. Doppler examinations were analyzed on an off-line station from tapes or Doppler strip charts. Early velocity, atrial velocity, end-diastolic velocity, pressure half-time, and mean gradient were obtained by digitizing tricuspid velocity curves. The incidence of "physiological" tricuspid prosthetic regurgitation was noted. Ten Doppler cycles were measured for each patient, and maximal, minimal, and average measurements were recorded. The mean values +/- SD of early velocity, atrial velocity, end-diastolic velocity, mean gradient, and pressure half-time and incidence of mild prosthetic regurgitation were reported for each type of prosthesis, as were highest Doppler measurements for each valve type. Average pressure half-time was significantly lower for St Jude than for heterograft prostheses (P = .04). There were no significant differences between the valve types for mean gradient, early velocity, or incidence of prosthetic regurgitation. Increasing prosthesis size was associated with lower average pressure half-time for heterograft prostheses (P = .024). Average differences (respiratory- and cycle-length-dependent) between maximal and minimal values for 10 cardiac cycles were established for each prosthesis. This study establishes normal ranges for Doppler hemodynamics of various tricuspid prostheses and emphasizes the importance of measuring multiple cycles for each tricuspid prosthesis, regardless of cardiac rhythm.

Treatment of prosthetic tricuspid valve thrombosis with low-dose tissue plasminogen activator

Reprint requesta: Mark L. Cohen, MD, Cardiovascular Division, Box 8086, Washington University School of Medicine, 660 South Euclid Ave., St. Louis, MO. 63110. 4/4/22910 Thrombosis of a prosthetic valve usually is life-threatening and generally requires emergency surgical intervention. Recently, there have been reports of nonsurgical treatment with tissue plasminogen activators (t-PA). In these reports, the doses employed invariably resulted in systemic fibrinogenolysis, and up to a 25 % incidence of bleeding has been reported.‘F2 To investigate the possibility that very low doses of t-PA would be equally efficacious, and by avoiding fibrinogenolysis would be potentially safer, we treated a patient with a thrombus on a St. Jude’s Medical mechanical tricuspid valve prosthesis (St. Jude Medical Inc., St. Paul, Minn.) with small doses of t-PA titrated by careful monitoring of clinical, echocardiographic, and coagulation parameters. The patient was a 30-year-old woman who underwent

Doppler echocardiography in prosthetic valve dysfunction. Diagnostic value in twenty cases.

We performed a retrospective study of 20 cases of prosthetic valve dysfunction which required reoperation and in which preoperative Doppler studies were performed. There were 13 mitral (3 mechanical, 10 bioprostheses) 5 aortic (1 mechanical and 4 bioprostheses), 1 pulmonary bioprosthesis and 1 mechanical tricuspid valve dysfunction. The aim of the study was to establish the diagnostic value of the Doppler examination by comparing the results with the operative findings. The parameters measured were: peak pressure gradient and mean pressure gradients in all prostheses, together with pressure half times and functional surface area in mitral and tricuspid valve prostheses. Cardiac catheterisation was performed in 6 cases before surgery. The diagnosis of prosthetic valve obstruction was correctly made, even in the 1 case with moderate stenosis. All cases of regurgitation were diagnosed and the topographical location of the leak was identified, except in 1 mechanical mitral valve prosthesis in which the regurgitant jet was detected only by continuous wave Doppler. Fourteen of the 20 cases were reoperated upon without catheterisation. These results suggest that Doppler echocardiography is a sensitive and specific diagnostic method of assessing prosthetic valve dysfunction. However, as the Doppler parameters are variable from one prosthesis to another, it is important to perform pulsed and continuous wave Doppler baseline studies in the immediate postoperative period as a reference in case of suspected valve dysfunction at a later stage.

Haemodynamic changes after tricuspid valve surgery. A recatheterization study in forty-five patients.

Changes of the central haemodynamics at rest and during exercise were evaluated in 45 patients who underwent tricuspid valve surgery. Tricuspid valve disease was associated with left heart valvular lesions in 42 patients, while isolated tricuspid valve lesions were present in 3 patients. The pre-operative evaluation showed marked impairment of cardiac function expressed by cardiomegaly, low physical working capacity, hypokinetic central circulation, elevated right atrial pressure and pulmonary hypertension in the majority of patients. Nineteen patients underwent tricuspid valve replacement and 26 tricuspid annuloplasty. The left heart valvular lesions were corrected by prosthetic valve replacement in all patients but one, who underwent mitral commissurotomy. The Björk-Shiley tilting disc valve prosthesis was used for all valve replacements. At postoperative evaluation the patients were classified in 3 groups: (1) Group TVR- 19 patients with well-functioning tricuspid valve prostheses; (2) Group TAP - 16 patients with good functional results in tricuspid annuloplasty; and (3) Group TAP-Failure - 10 patients in whom significant tricuspid incompetence was observed. The overall response to surgery in groups TVR and TAP was about the same, leading to an increase in working capacity and cardiac output and a decrease in heart volume, right atrial pressure and pulmonary hypertension. In the TAP-failure group, this response was limited to an increase in cardiac output and mainly attributable to the corrected left heart lesions. Sustained pulmonary hypertension, failing left ventricular myocardium, residual left heart lesions and anatomical tricuspid valve changes were the likely causes of TAP-failure, which could not be predicted from the pre-operative evaluation.

A guide to the radiographic identification of prosthetic heart valves.

To facilitate the radiographic identification of prosthetic heart valves, radiographic silhouettes of various aortic, mitral and tricuspid valve prostheses were analyzed and shematized. Forty different prosthetic valve models (heterograft and mechanical) were obtained from seven domestic manufacturers. Each prosthesis was positioned to approximate the aortic, mitral or tricuspid valve anulus plane. The valves were then radiographed and photographed as they would appear in posteronanterior and left lateral chest radiographs. The radiographic silhouettes were examined and a scheme was designed to enable easy, yet accurate, differentiation of the many heart valve prostheses. Illustrations of the various valve types are presented as they would appear in routine chest radiographs.

Malfunction of tricuspid valve prosthesis shown by isotope angiocardiography

Isotope angiocardiography established prosthetic tricuspid valve obstruction in a patient 6 years after triple valve replacement. Thrombus formation is a common complication of prosthetic cardiac valves, particularly in the tricuspid position where engagement of cage with myocardium is an additional potentially obstructive hazard. Comparison is made between the information yield of the isotope investigation and cardiac catheterization with contrast cineangiography. It is suggested that the isotope technique can noninvasively provide valuable anatomic and functional data, particularly where the right side of the heart is to be examined.

Massive pulmonary hemorrhagic infarction.

While revascularization of acutely ischemic regions of the brain may result in hemorrhagic infarction, this is not a recognized hazard of pulmonary revascularization. Three patients recently entered the UCLA Medical Center with severe pulmonary ischemia (obstructed tricuspid valve prosthesis, obstructed atrial baffle following repair of transposition of the great vessels, massive pulmonary embolism) and died from massive tracheobronchial hemorrhage following successful surgical restoration of pulmonary blood flow. In each patient, severe pulmonary edema developed while left atrial pressure was below normal, indicating loss of lung capillary integrity. There was an inverse relationship between the duration of preexisting ischemia and the onset of rapidity of developing hemorrhagic infarction following restoration of normal pulmonary blood flow. This observation suggests that the lung capillary wall may be at least partially protected by collateral circulation when the ischemia develops slowly. Awareness of this potentially lethal complication may allow for earlier and more appropriate management.

Two-Stage Tricuspid Valve Replacement for Mixed Bacterial Endocarditis

Mixed<i>Staphylococcus aureus</i>and<i>Enterobacter</i>endocarditis of the tricuspid valve in a heroin addict failed to respond to large doses of antibiotics to which these organisms were sensitive. However, following tricuspid valvulectomy, the synergistic combination of cefanone and gentamicin sulfate (Garamycin) effectively eradicated the infection. Though the patient tolerated absence of the tricuspid valve for eight weeks, his exercise capacity was limited until a tricuspid valve prosthesis was inserted. The<i>Enterobacter</i>strain isolated from this patient inactivated penicillin and oxacillin in broth culture. Studies of a sonicate from this organism demonstrated considerable β-lactamase activity against penicillin and oxacillin and less against cefanone. Those findings suggest a mechanism by which the presence of<i>Enterobacter</i>perpetuated staphylococcal endocarditis despite prolonged therapy with antibiotics.

Infective endocarditis in drug addicts. Experiences with medical and surgical treatment.

Isolated tricuspid valvular endocarditis is no longer rare, and its increasing incidence has paralleled the rise in heroin addiction. In the period between December, 1969 and December, 1971, 16 episodes of bacterial endocarditis occurred in 13 individual drug abusers at the Ben Taub General Hospital, Houston. The tricuspid valve (TV) was involved in all cases. Two patients required surgery during the acute infection; one underwent total excision of the TV without replacement, and one received aortic and TV prostheses because of progressive heart failure. Antibiotic therapy was individualized and guided by tube dilution sensitivities and serum bactericidal levels. In view of the excellent response to antibiotic therapy, surgery for infected prosthetic or natural valves is presently reserved for those patients with progressive cardiac failure or infections unresponsive to medical therapy.

Late Thrombotic Obstruction of Starr-Edwards Tricuspid Valve Prosthesis

Two patients developed late thrombotic obstruction of a Starr-Edwards tricuspid valve prosthesis, one subsequent to restriction of ball motion by interfering subvalvular muscular structures, and the other during Candida parakrusei endocarditis. Late prosthetic tricuspid valve thrombosis is uncommon, but may occur if a preceding event causes the prosthesis to malfunction.

Total prosthetic replacement of atrioventricular valves in the dog. 3. local tissue reactions in the heart caused by tricuspid valve prostheses.

The metal parts of cardiac valve prostheses cause reactions in the surrounding tissues of the heart. In some dogs rather abnormal reactions were found, and were attributed to corrosion of the stainless steel in the cage of the valve with subsequent local metallosis of the heart and microscopic symptoms of corrosion disease.

EBSTEIN'S MALFORMATION OF THE TRICUSPID VALVE. METHOD OF SURGICAL CORRECTION UTILIZING A BALL-VALVE PROSTHESIS AND DELAYED CLOSURE OF ATRIAL SEPTAL DEFECT.

Two cases of complete correction of Ebstein's malformation are presented. The deformed tricuspid valve was excised. A ball-valve prosthesis was anchored at the true annulus. This procedure removes the obstruction to right ventricular outflow, eliminates tricuspid insufficiency, increases right ventricular diastolic capacity, and improves the pumping action of the right ventricle by increasing the size and effectiveness of the pump chamber. Preoperatively, both patients were cyanotic because of large right-to-left shunts at the atrial level. No attempt was made to close the associated atrial septal defect in our first case. This patient continued to shunt right-to-left postoperatively but expired early in the postoperative period as a result of right-heart failure. A flap-valve type closure of the large associated atrial septal defect in the second patient with Ebstein's malformation permitted right-to-left shunting until the right ventricle became competent to pump the entire venous return to the lungs. About two weeks after surgery the right-to-left shunting ceased in this patient. Both patients developed complete heart block during the tricuspid valve prosthesis insertion. This complication was compensated for by a myocardial electrode and external pacemaker in the early postoperative interval. The second patient was discharged in an asymptomatic condition following insertion of an implantable pacemaker. A possible method for avoiding heart block in these cases in the future is discussed.