Long-term results in 1375 patients undergoing valve replacement with the Starr-Edwards cloth-covered steel ball prosthesis

The development of valvular heart surgery over the past 50 years (1947-1997): personal recollections

The development of valvular heart surgery over the past 50 years has required the efforts and creative genius of many surgical pioneers. It has been filled with exhilarating short-term successes and some devastating failures. This article traces the 50 years of persistence and determination that have brought us to a time when the majority of patients with heart valve disease can be returned to a happy and fulfilling life by valvuloplasty or by valve replacement.

Echocardiography can detect cloth cover tears in fully covered Starr-Edwards valves: a long-term clinical and echocardiographic study

The incidence of cloth cover tears in fully covered Starr-Edwards valves, as assessed by autopsy or repeat surgery, is approximately 1% per patient-year. However, no echocardiographic study has explored this phenomenon. This study was designed as a one-time observational study and aimed to explore the ability of two-dimensional transthoracic echocardiography to identify cloth cover tears in 35 late survivors with 38 fully covered Starr-Edwards valves who had been operated on 20 to 24 years earlier. The hemodynamic profile, clinical status, and valve-related complications in this highly selected group of late survivors were also studied. Five patients also underwent transesophageal echocardiography. An elongated echogenic mass attached to the prosthetic valve cage and floating downstream was considered indicative of cloth tear. There were 16 patients with aortic valve prostheses, 16 with mitral valve prostheses, and three with double prosthetic valves. In six (17.1%) patients (four with aortic valve prostheses, two with mitral valve prostheses), an echogenic mass suggestive of cloth cover tear was detected, which was confirmed by transesophageal echocardiography in three patients. In two patients the echocardiographic finding was confirmed at surgery. The initial presentation of these six patients was endocarditis, possible embolism, unexplained dyspnea, and weakness in one patient each. Two patients were asymptomatic. There was no evidence of significant prosthetic valve malfunction in any patient. The transvalvular gradients were similar in patients with and without cloth cover tears. Echocardiographic findings highly suggestive of cloth cover tears are not uncommon and can be detected in the third postoperative decade in patients with fully covered Starr-Edwards valves. A prospective study to evaluate the clinical significance of an incidental echocardiographic finding suggestive of cloth cover tears in asymptomatic patients with these valve models is warranted.

Long-term outcome of patients who received Starr-Edwards valves between 1965 and 1977

To determine the risk factors relating to long-term outcomes of the Starr-Edwards ball valve, data from 150 patients (75 males, 75 females; age range 9-67 years); who underwent valve replacement (44 aortic, 106 mitral) between 1965 and 1977 at Niigata University were reviewed retrospectively. Valve models 6120/6320 and 1260/2320 were mainly used in mitral and aortic positions, respectively. The cumulative follow-up period was 2227.4 patient-years. Using the Kaplan-Meier life-table method, actuarial probability of freedom from valve-related mortality, morbidity and thromboembolism were analysed. Thirteen patients died from various causes during hospitalization. Some 80 patients suffered 97 instances of valve-related morbidity and 58 died during follow-up (up to 28 years). Patient age > 50 years affected the actuarial probability of freedom from valve-related mortality in the entire group (P < 0.05). Valve type and the year of operation were discriminative predictors of thromboembolic complications in the entire group (both P < 0.05) and in the mitral valve replacement group (P < 0.01 and P < 0.001). However, only the year of operation affected the actuarial probability of freedom from all valve-related morbidity in the entire group and in the mitral valve replacement group (both P < 0.05). Univariate analysis revealed that age at surgery, valve type, and the year of operation were related to late postoperative outcome in patients who received a Starr-Edwards ball valve between 1965 and 1977.

Conservative surgery of the mitral valve: a report of the first 100 cases from one unit and one surgeon

OBJECTIVE

To report the first 100 mitral valve repairs performed in a unit with an aggressive approach to conservative mitral valve surgery.

DESIGN

Case notes were reviewed retrospectively and patients invited for clinical examination and cross sectional and Doppler echocardiography.

SETTING

Tertiary cardiothoracic referral centre.

PATIENTS

Between December 1985 and April 1991 mitral valve repair was carried out on 100 patients (66 males). Patients with pure mitral stenosis were excluded. Sixty seven had degenerative and 15 rheumatic mitral valve disease. Median age was 66 (range 12 to 79) years, with an interquartile range of 59 to 71 years.

INTERVENTIONS

Operative procedures included annuloplasty ring in 97, resection of the posterior leaflet in 67, resection of endocarditic portion of posterior leaflet in four, commissurotomy in six, and correction of anterior leaflet abnormalities in seven. Thirty nine concomitant cardiac procedures were performed in 32 patients. Six operations were emergencies, and three of these required concomitant procedures.

MAIN OUTCOME MEASURES

Mortality, operative failure rate, patients' functional state and degree of residual mitral regurgitation, incidence of thromboembolism, and endocarditis.

RESULTS

Follow up ranged from one to 59 months, median 14 months, and an interquartile range of four to 23.5 months. Early mortality was 1%, late mortality 5%, and there was a 2% reoperation rate. Eighty four patients had moderate to severe mitral regurgitation preoperatively. At follow up mitral regurgitation was absent or mild in 78. Eighty six patients were in New York Heart Association (NYHA) class I-II at follow up compared with 80 in NYHA class III-IV preoperatively. There were no thromboembolic events.

CONCLUSION

This study shows that satisfactory results can be obtained with mitral valve repair in a fairly elderly population with a high incidence of concomitant cardiac disorders. We suggest that these encouraging results will lead to earlier mitral valve repair in mitral regurgitation.

Multicenter experience with balloon mitral commissurotomy. NHLBI Balloon Valvuloplasty Registry Report on immediate and 30-day follow-up results. The National Heart, Lung, and Blood Institute Balloon Valvuloplasty Registry Participants

BACKGROUND

Balloon mitral commissurotomy can increase mitral valve areas and reduce symptoms in selected patients with mitral stenosis. The National Heart, Lung, and Blood Institute Balloon Valvuloplasty Registry was organized to address concerns regarding differences in patient selection and technique and to report the current clinical outcome.

METHODS AND RESULTS

In 24 cooperating centers, 738 patients had balloon mitral commissurotomy. Baseline clinical, echo Doppler, and cardiac catheterization data, procedure details, and hemodynamic and 30-day clinical outcome were reported. Overall, 81% of the patients were women (mean age, 54 +/- 15 years), and 24% had moderate or severe other valvular lesions. When single- and double-balloon procedures were compared, the final mitral valve area was larger (1.7 +/- 0.7 versus 2.0 +/- 0.8 cm2, p = 0.0009), increase in mitral regurgitation was similar (4% versus 12%, p = 0.08), and interatrial shunts occurred more frequently (2% versus 12%, p = 0.04) after double-balloon procedures. Increase in mitral valve area was weakly related to mitral valve morphology as assessed by an echo score (r = -0.15). Multivariate predictors of improved clinical status at 30 days were cases performed in larger-volume centers, baseline mitral valve area greater than 0.5 cm2, and age less than 70 years. At 30-day follow-up, 4% of the patients with completed procedures had mitral valve surgery, 3% had died, and 83% had their overall condition improved. Patients with mixed mitral stenosis or regurgitation and isolated mitral stenosis had a similar course, but fewer patients with multivalve disease became asymptomatic.

CONCLUSIONS

Balloon mitral commissurotomy, as practiced in a broad range of experienced centers, produced significant short-term hemodynamic and clinical improvements. Balloon mitral commissurotomy can be considered an effective treatment option in patients with symptomatic mitral stenosis.

Case-matched comparison of mitral valve replacement and repair

Carpentier's techniques of prosthetic ring mitral valve repair for mitral regurgitation offer the potential for immediate and long-term improvement in valve function without the necessity of replacing the native valve with a prosthesis. A consecutive, case-matched series of 65 patients with prosthetic ring mitral valve repair was compared with 65 patients undergoing mitral valve replacement for mitral regurgitation. The aortic cross-clamp time was 57 +/- 33 minutes in the repair operations and 41 +/- 25 minutes in the replacement operations (p = 0.003). The cardiopulmonary bypass time was 154 +/- 44 minutes in the repair operations and 113 +/- 41 minutes in the replacement operations (p = 0.0001). There were no myocardial infarctions in the hospital in either group. Hospital death was noted in 1.5% of repairs and 4.6% of replacements (p = not significant). Survival at 4 years was 0.84 for repairs and 0.82 for replacements (p = not significant). Freedom from reoperation to replace the mitral valve at 4 years was 62 of 65 patients in the repair group and 64 of 65 patients in the replacement group (p = not significant). In-hospital and midterm results in a closely matched population show that mitral valve repair yields results comparable with those of replacement despite a more difficult procedure. The benefits of maintaining the native valve with chordal and papillary muscle structure intact and avoidance of prosthetic valve implantation may then become apparent with longer follow-up.

Sudden cardiac death after aortic valve surgery: incidence and concomitant factors

A retrospective analysis of 599 consecutive patients after aortic valve surgery aged 7-82 years (mean 56) was performed. During a follow-up of 1-14 years (mean 4.7 years) a 4-week perioperative mortality of 6.9% and a late annual mortality of 3.6% were observed. Sudden cardiac death was the most frequent single cause of death, accounting for 24% of all deaths. Patients dying suddenly were younger than patients dying from other causes (51 +/- 17 vs. 59 +/- 14 years, p less than 0.05) and showed more left ventricular hypertrophy by electrocardiographic criteria when compared with matched survivors (mean Estes score 5.2 +/- 2.4 vs. 2.8 +/- 1.9; p less than 0.01) and with patients dying nonsuddenly (mean Estes score 5.2 +/- 2.4 vs. 1.8 +/- 1.8; p less than 0.01). Ventricular premature beats in the resting electrocardiogram were more prevalent in patients dying suddenly than in matched survivors (55 vs. 20%; p less than 0.025) as well as in patients dying from other causes (55 vs. 25%; p less than 0.05). In addition, there were more intracardiac conduction disturbances and more ungrafted coronary vessels with insignificant stenoses at the time of surgery in sudden death patients. Our findings suggest that after aortic valve replacement patients with left ventricular hypertrophy, bundle-branch block, and ventricular premature beats in the resting electrocardiogram are at increased risk for sudden cardiac death. A possible etiological role of concomitant coronary artery disease must be considered.

Current concepts of mitral valve reconstruction for mitral insufficiency

In recent years, there has been a renewed interest in surgical reconstruction of the insufficient mitral valve because of reconfirmation of the limitations of existing prosthetic and bioprosthetic valves. A follow-up study, including late functional data, of 148 patients who underwent mitral valve reconstruction at our institution was combined with a review of the literature to assess the current status of mitral reconstruction. The results indicate that mitral reconstruction by Carpentier techniques is widely applicable, durable, and relatively free of complication. Freedom from late thromboembolic and anticoagulant complications is particularly notable. These factors could prove to justify earlier operative intervention in patients with mitral insufficiency before permanent myocardial damage evolves. As mitral valve reconstruction techniques become more familiar and widely used, mitral reconstruction may become the operative procedure of choice for mitral insufficiency, especially insufficiency due to degenerative disease.

Valve replacement in narrow aortic roots: serial hemodynamics and long-term clinical outcome

No long-term data are available that correlate clinical outcome with serial hemodynamic studies for small-diameter (17-mm or 19-mm) aortic prostheses implanted without enlargement of the annulus. After insertion of these valves without annuloplasty, 52 patients underwent resting catheterization and were followed up at the Surgery Clinic of the National Heart, Lung, and Blood Institute for 295 patient-years (mean, 5.7 years per patient). At similar flow rates, peak systolic gradients across 17-mm Björk-Shiley aortic prostheses (N = 6) tended to exceed those of the 19-mm Björk-Shiley model (N = 38); these gradients averaged 30 +/- 6 mm Hg (mean +/- standard error of the mean) and 20 +/- 2 mm Hg, respectively (p = .053). Those patients with 19-mm Hancock (N = 4) and St. Jude Medical valves (N = 4) were studied, and the lowest prosthetic gradients were found with the St. Jude Medical prosthesis (mean, 3 +/- 2 mm Hg). Aortic gradient was independent of flow for 17-mm but not for 19-mm Björk-Shiley valves. There was no difference in calculated effective orifice area with respect to valve size. Effective orifice area and prosthetic gradients were stable during intervals of 2 to 12 years in 10 patients who underwent additional catheterizations. No association was found between prosthetic gradients, flows, or calculated orifice areas and early or late functional class. Actuarial survival was 86 +/- 5% at 5 years, 83 +/- 5% at 8 years, 71 +/- 9% at 10 years, and 60 +/- 12% at 12 years of complete follow-up. It is concluded that small aortic prostheses provide acceptable palliation for long periods and that resting hemodynamic studies have a limited predictive value for long-term prognosis.

Experiences with 1643 porcine prosthetic valves in 1492 patients

Sixteen hundred and forty-three porcine prosthetic values (1102 Carpentier-Edwards, 541 Hancock) were implanted in 1492 patients at New York University Medical Center between January 1976 and June 1983. The aortic valve alone was replaced in 786 patients (53%), mitral valve alone in 556 (37%), and multiple valves in 143 patients (9.6%). Concomitant coronary artery bypass was performed in 326 patients (22%). There were 116 deaths within 30 days of operation (7.8%). Follow-up (mean: 42 months) was completed in 94% of survivors and revealed that late survival from cardiac-related death was 87% at 5 years and 81% at 7 years, with no significant difference between the Carpentier-Edwards and Hancock patients. Late thromboembolic complications, however, were significantly more frequent in Hancock patients at all intervals from 1-7 years (p less than 0.05), whether in the aortic or mitral position. Patients with coronary artery disease who had concomitant coronary bypass showed a survival from late cardiac death that did not differ significantly from that of patients undergoing valve replacement alone. Before operation, 87% of patients were in New York Heart Association Class III or IV, but after operation 80% were in Class I or II. Late anticoagulant complications, endocarditis, and valve dysfunction were relatively rare. These results from a series of such size, duration, and representative numbers of two types of porcine bioprosthesis confirm excellent results with porcine prostheses in the first 4-5 years following operation.

Starr-Edwards aortic prosthesis: a 20-year retrospective study

Over the years the Starr Edwards prosthesis has demonstrated a high durability and improved survival in patients with severe aortic stenosis or insufficiency. While the ideal valve prosthesis is not yet available, the Starr-Edwards valve in most instances demonstrates an adequate hemodynamic performance, does not degenerate throughout the human life span, is biocompatible, and is inserted reliably without requiring unique technical dexterity. Despite occasional valve-related complications with early models, beneficial effects of valve replacement are clearly seen in patients with a reversible myocardial dysfunction, a lower level New York Heart Association functional class (II to III), and who survive the early postoperative period and the first year. Long-term complications seen with the Starr-Edwards valve are primarily thromboembolism, endocarditis, hemolysis, and anticoagulation related complications. Despite good operative results, the major cause of deaths in these patients remains cardiac.

Results of triple valve replacement in 91 patients: perioperative mortality and long-term follow-up

Between 1961 and 1984, 91 patients underwent simultaneous triple valve replacement at the Mayo Clinic. Of the 273 prosthetic valves used, 77% were Starr-Edwards. Perioperative (30 day) mortality was 24% to 27% between 1962 and 1974 and 7% between 1975 and 1983 (p = .17). In patients with NYHA class IV symptoms, perioperative mortality was 44%, and in those with milder symptoms, it was 8% (p less than .0001). The median follow-up was 7.5 years (range, 6 weeks to 20 years). Cumulative survival, which was calculated taking into consideration perioperative mortality, was 64% at 1 year, 55% at 5 years, 40% at 10 years, and 25% at 15 years. Multivariate analysis identified preoperative functional class and age as predictors of late survival. Among causes of late mortality were sudden death in 32.5%, congestive heart failure in 15%, thromboembolism in 12.5%, prosthetic valve dysfunction in 7.5%, and infective endocarditis in 5%. Late complications included systemic emboli in 42% (embolic rate, 12.3 events per 100 patient-years), bleeding in 22%, myocardial infarction in 16%, and infective endocarditis in 6%. Eight patients required reoperation for prosthetic valve dysfunction, and 12 patients had permanent pacemakers. Of the 29 patients still alive, 79% are in NYHA class I or II. In summary, perioperative mortality after triple valve replacement appears to be declining; long-term survival in 30 day survivors is similar to that after single valve replacement and excellent symptomatic improvement can be obtained, although morbidity is high.

Mechanical trauma to red blood cells caused by Björk-Shiley and Carpentier-Edwards heart valves

The haemolytic properties of mechanical and biologic valve prostheses are well established, and it is known that they can shorten red cell survival time (1, 2). Their effects on red cell deformability are not known, however. A comparative study was therefore made of two valve types--Björk-Shiley (BS) and Carpentier-Edwards (CE). Thirty-nine patients with normally functioning valve prostheses (23 BS, 16 CE) were studied at least one year after surgery, by assessing red cell deformability measured as red cell filtration rate (RFR), red cell survival half-time with the Cr-51 isotope method (Cr-51 T1/2) and plasma-haemoglobin (P-Hb). The BS valve was shown to be more traumatic to the cells than the CE valve and effected greater reduction of the deformability of these cells. Significant intercorrelations were found between RFR, CR-51 T1/2 and P-Hb.

Aortic and mitral valve incompetence: long-term follow-up (10 to 19 years) of patients treated with the Starr-Edwards prosthesis

The long-term course (mean 15 years) of 336 patients with valvular incompetence who underwent Starr-Edwards ball valve implantation between 1962 and 1971 was reviewed. Eighteen patients (10%) with aortic valve replacement and 24 (16%) with mitral valve replacement died early postoperatively. Mortality remained high (31%) in the first 3 years after aortic valve replacement; it was highest (13%) in the first year after mitral valve replacement and then approached the normal rate. The most common mode of death was sudden death after aortic and cardiac failure after mitral valve replacement. At follow-up, 76% of survivors had improved symptomatically. Three instances of primary valve malfunction occurred. The probability of freedom from thromboembolism at 15 years postoperatively was 56% for aortic valve replacement and 52% for mitral valve replacement. The Starr-Edwards valve prosthesis is durable over prolonged follow-up period, but thromboembolism remains a persistent problem. Survival may be normal for patients surviving the early postoperative years.

Prosthetic valve endocarditis

Fifty-three (3.6%; actuarially 4.1% at 48 months) of 1465 consecutive in-hospital survivors of valve replacement from 1975 to July 1979 (aortic, mitral, or aortic and mitral, only one untraced) developed prosthetic valve endocarditis (PVE). Incremental risk factors for developing PVE were native valve endocarditis (p less than .0001), black race (p = .0001), mechanical prosthesis (vs bioprosthesis) (p = .005), male sex (p = .04), and longer cardiopulmonary bypass time (p = .09). In general, the hazard function for developing PVE was greatest at 3 weeks after valve replacement. Patients with native valve endocarditis had a tendency to develop PVE early after valve replacement, as did patients in whom mechanical prostheses were used. PVE associated with Staphylococcus epidermidis tended to appear within 6 months of valve replacement, whereas streptococcal PVE tended to appear later after valve replacement. PVE took an atypical form in some patients, but patients with possible PVE (n = 6) had the same findings as those with certain PVE (n = 47). In 11 patients bacteriologic confirmation of PVE was not obtained. The typical prosthetic and periprosthetic characteristics of PVE were present in 30 of the 40 cases in which observations were possible. PVE is a serious condition; 34 (64%) of our 53 patients died. Most deaths occurred within 3 months of the first evidence of PVE. Recovery of some patients is possible with appropriate medical and surgical treatment, but more intense preventive measures are indicated.

Wear of the metallic studs on the composite seat of the 2320 Starr-Edwards aortic valve and its clinical consequences

The 2320 Starr-Edwards aortic valve has a composite seat with metallic studs that protrude through the cloth. Certain clinical and morphologic findings are described in 6 patients who had this prosthesis in situ for 50 to 144 months (mean 92). Considerable disruption of the cloth covering both struts and base, and varying degrees of wear of the metallic studs that line the luminal side of the prosthetic ring occurred in each. Excessive stud wear resulted in severe disruption of the cloth lining the interior of the prosthetic ring. Cloth disruption may be associated with hemolytic anemia, embolic consequences, or both. Of our 6 patients, 4 had severe hemolytic anemia, 4 had neurologic events compatible with emboli and 1 died suddenly. Stud wear as observed in the 2320 series Starr-Edwards prosthesis also may occur in the models 2310 and 2400 prostheses, which have the same composite seat.

Bioengineering aspects of heart valve replacement

Biomedical engineering inputs have been important in the design, development and testing of substitute heart valves as well as in the pre- and post-operative management of patients with cardiac valve disease. This paper is a review of heart valve replacement whose goal is the enhancement of future bioengineering contributions. We review the approach to the patient with valvular heart disease, and the sources of early and late postoperative pathology with emphasis on complications of the prostheses used. Major significant problem areas relate to the noninvasive evaluation of cardiovascular function (both before and after surgery), device design, hemodynamics, and the need for thromboresistant and durable materials.

Clinical experience with the Smeloff-Cutter prosthesis: 1- to 12-year follow-up

To determine the long-term results of aortic valve replacement with the Smeloff-Cutter prosthesis, the fate of 358 of 459 (78%) consecutive patients was determined 1 to 12 years postoperatively. There were 319 male patients (70%). Mean age at operation was 57 years (range, 15 to 84 years). Aortic stenosis was the dominant lesion in 267 patients (58%) and aortic regurgitation in 133 patients (29%). Fifty-nine patients (13%) had both aortic stenosis and regurgitation. In addition to aortic valve replacement, 93 patients (20%) had coronary artery bypass, 30 (6.5%) had mitral commissurotomy, 23 (5%) had mitral valve replacement, and 41 (9%) had other procedures. Preoperative status by New York Heart Association Functional Class was: Class I, 3 (1%); Class II, 39 (8%); Class III, 148 (32%); and Class IV, 269 (59%). Operative (30-day) mortality was 8.5% (39 out of 459). Functional improvement was obtained in all postoperative survivors: 345 (82%), Class I; 63 (15%), Class II; and 12 (3%), Class III. A perivalvular leak developed in 6 patients (1%) and subacute bacterial endocarditis in five (1%). Actuarial long-term survival was 80% at 5 years and 71% at 8 years. Thromboembolism occurred in 34 patients (9.5%). The incidence of thromboembolism per 100 patient-years for patients receiving no anticoagulants was 5.4; antiplatelet agents, 2.9; and Coumadin (sodium warfarin), 2.6. Major thromboembolism was uncommon in patients on a regimen of sodium warfarin but major morbidity from bleeding was significant.

Carotid ligation for recurrent ischemia due to inaccessible carotid obstruction. Examination of the rationale of this treatment

Experiences with a patient with symptomatic obstruction to the carotid artery in its petrous segment are described. In spite of the severe stenosis of this vessel, complete arteriography demonstrated excellent perfusion of the symptomatic eye and hemisphere and an ample collateral reserve. Funduscopy confirmed the clinical impression that recurrent retinal and hemispheric ischemia in this patient was the result of microembolism rather than intracranial hemodynamic insufficiency. Consequently, extracranial-intracranial (EC-IC) bypass was believed to offer little benefit to this patient. Abrupt ligation of the internal carotid artery in the neck proved to be an effective method for arresting the embolic discharge from this vessel's inaccessible obstruction, and resulted in prompt and complete relief of ischemic symptoms. It is concluded that identifying the mechanism(s) responsible for recurrent ischemia past uncorrectable carotid obstructions is of paramount importance in order to establish the most appropriate treatment(s). Carotid occlusion is an effective surgical remedy for terminating microembolism from this vessel when it is diseased and incompletely obstructed, and should be considered in selected patients. The importance of angiographic evaluation of naturally occurring EC-IC anastomotic connections in addition to the assessment of intracranial collateral reserves in cases of carotid occlusion is also emphasized.

Porcine valves

To date, the glutaraldehyde porcine aortic valve xenograft has proved a good choice for valve replacement in both the aortic and mitral positions. Late thromboembolisms in the absence of long-term anticoagulation is virtually nonexistent in aortic valve replacement and very low in mitral valve replacement patients without a predisposing history. The hemodynamic performance of the porcine xenograft is adequate and comparable to that of mechanical prostheses. The potential for improved hydrodynamic function, particularly of very small sized valves, is great and already being realized. In spite of over 8 yr of xenograft experience, long-term durability remains the primary concern. Histologic study suggests that these valves undergo progressive postimplantation morphological alteration. However, to date, the incidence of tissue failure is very low. Although detailed reports of long-term valve series are surprisingly few, at present, there is no valve replacement device with a 10-yr experience proven structural integrity and a negligible incidence of valve-related morbidity. It will be 3-4 yr before a significant number of porcine xenograft patients either reach this point or experience valve failure. While this review of the valve literature does not permit a statistical comparison of valve types, we feel that it does allow us to attempt a general projection. On the basis of combined survival and valve-related complication rates, at 4 yr, the porcine xenograft appears to be a better choice than the mechanical prosthesis. Excessive tissue failure during the next 3-4 yr might reverse this opinion. However, even if an increase in valve failure does occur, the advantage of noncatastrophic disfunction and decreased valve-related complications may balance the risk of reoperative morbidity and mortality and continue to favor the porcine exnograft. Thus we could speculate that: (1) The tissue valve would be the valve of choice if (A) durability of 10 yr or more is proven, and valve complications with the xenograft remain as presently reported; (B) the incidence of valve complications with the mechanical prostheses at 10-yr follow-up continues to increase. (2) Mechanical prostheses would be the valves of choice if (A) xenograft valve failure is greater than 20% at 10 yr of follow-up; (B) the incidence of valve complications with the mechanical prostheses remains unchanged. (3) The choice of xenograft versus mechanical prosthesis will remain an open issue if valve failure and related complications with both types of device remain below 20% at 10-yr follow-up...

Congestive heart failure secondary to diffuse organized biventricular mural thrombus following mitral valve replacement

A 52-year-old woman underwent mitral valve replacement for progresive mitral regurgitation. Despite anticoagulation therapy, pulmonary thromboemboli occurred. Progressive heart failure developed and fatal intracerebral hemorrhage occurred four years after valve replacement. Autopsy findings revealed a normal-sized heart with minimal ventricular hypertrophy. However, there was extensive organized mural thrombosis involving both ventricles. Endocardial thickening by diffuse organized thrombosis is an uncommon but severe complication following prosthetic valve replacement and may result in intractable heart failure from endocardial rigidity.

Factors relating to late sudden death in patients having aortic valve replacement

The preoperative and postoperative characteristics of a group of 16 patients who died unexpectedly and a control group of 52 late survivors with aortic protheses are reviewed. There were no preoperative differences between the groups for duration of congestive heart failure, electrocardiographic findings, cardiothoracic ratio, or hemodynamic findings. However, on the standard electrocardiogram postoperatively, there were more ventricular arrhythmias in the patients who died suddenly (7 of 16 or 44%) compared with the survivors (5 of 49 or 10%) (p less than 0.05). There were more patients with congestive failure in the study group (10 of 16 or 62%) compared with the controls (4 of 52 or 8%) (p less than 0.05). Patients exhibiting these findings are at risk of sudden death. Arrhythmia monitoring prior to discharge may also be helpful in selecting patients for antiarrhythmia treatment.

Central haemodynamics at rest and during exercise before and after combined aortic and mitral valve replacement with the Björk-Shiley tilting disc valve prosthesis

Pre- and postoperative haemodynamics were compared in 36 patients with combined aortic and mitral valvular disease. These patients suffered from markedly restricted cardiac function in terms of cardiomegaly, low physical working capacity, hypokinetic central circulation and pulmonary hypertension. Valve replacement was performed with the Björk-Shiley Delrin disc (10) and pyrolytic carbon disc (26) prostheses and followed by subjective improvement in the majority of patients. Heart volume decreased and working capacity increased in average significantly, but were not restored to normal. The main response to surgery was a shift towards a normokinetic circulation, although many patients remained hypokinetic. There was also regression of pulmonary hypertension as a result of reduced left atrial pressure and pulmonary vascular resistance. In spite of a significant decrease in left atrial mean pressure, it remained elevated with prominent v-waves in many patients, particularly during exercise. Marked v-waves in the right atrial pressure curves were also noted in one third of the patients. Only one patient, however, suffered from clinically manifested tricuspid incompetence. This study shows the benefits of combined aortic and mitral valve replacement, even in patients with longterm haemodynamic burden on the myocardium. Although the central haemodynamics were almost normalized at rest, abnormal responses persisted during exercise.

Complications due to cloth wear in cloth-covered Starr-Edwards aortic and mitral valve prostheses--and their management

Five cases of complications due to cloth wear in cloth-covered composite-seat Starr-Edwards aortic and mitral valvular prostheses are described. The complications of cloth wear were recurrent systemic emboli in three patients, two with aortic and one with mitral prosthesis, and severe hemolytic anemia in two patients with aortic prosthesis. The over-all incidence of clinically significant complications due to cloth wear in aortic and mitral valve prosthesis was 2.5 per cent. The diagnosis of cloth wear is impossible before reoperation and it was made by exclusion of other causes of recurrent transient cerebral ischemic attacks or systemic emboli and by exclusion of other causes of hemolytic anemia. Clinical and laboratory findings suggestive of cloth wear are described. Aggressive management of complications of cloth wear by reoperation is likely to prevent disabling or lethal consequences. Porcine xenograft aortic and mitral bioprostheses were used in these patients to replace the cloth-covered valvular prostheses. The symptoms due to cloth wear were abolished in all patients by reoperation, and all patients are off anticoagulants postoperatively. The operative mortality rate for reoperation in this small group of patients was zero.