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PubMed1979

Clinical and hemodynamic results after combined aortic and mitral valve replacement with the Lillehei-Kaster pivoting disc valve.

Combined mitral and aortic valve replacement with the Lillehei-Kaster pivoting disc valve prosthesis was performed in 23 patients. Hospital mortality rate was 8.3 per cent. Detailed postoperative clinical and hemodynamic studies were performed after a mean follow-up period of 24.4 months. Replacement of both valves had resulted in a marked symptomatic and hemodynamic improvement with a normal or nearly normal resting value of cardiac output, pulmonary arterial pressure, and pulmonary vascular resistance while left ventricular end-diastolic pressure (LVEDP) had increased significantly. The rise in left ventricular end-diastolic pressure most probably might be related to the simultaneous rise in cardiac output (Starling mechanism), reflecting the severity and irreversibility of the underlying myocardial disease. Most patients also had systolic gradient across the aortic prosthesis, as well as diastolic gradient across the mitral prosthesis. The gradients across the mitral prosthesis were approximately the same as seen after single valve replacement, while the pressure gradients across the aortic prosthesis were somewhat smaller than previously reported. Angiographic studies of the aortic valve movement indicated that the opening angle of the disc was approximately 60 degrees, and thus less than according to the valve specifications.

Adult↗
PubMed1978

Tissue valve replacement of prosthetic heart valves for thromboembolism.

Twenty-five patients who had repeated thromboemboli from a prosthetic mitral valve were treated with reoperation using a tissue valve prosthesis. Reoperation was performed an average of 4.0 years after the original valve replacement in 14 men and 11 women, with an average age of 50 (range 35 to 65) years. A stented allograft was used in the first 7 patients and a porcine xenograft in the last 18 patients. There were one hospital death and two late deaths. With the first prosthetic valve there were 66 documented embolic episodes in 101.5 patient years (0.65 embolus/year). Only four embolic episodes in 67.4 patient years (0.059 embolus/year) occurred after tissue valve replacement (P less than 0.001). These results indicate that in patients with recurrent or severe embolization after prosthetic heart valve replacement, rereplacement with a tissue prosthesis can be safely performed and significantly reduces the likelihood that additional embolic episodes will occur.

Adult↗
PubMed1983

Long-term results of tricuspid valve replacement and the problem of prosthetic valve thrombosis.

Observations in 71 patients having tricuspid valve replacement over a 14-year period are described. The operative mortality rate was 10% and the actuarial survival rate was 73% at 5 years and 47% at 10 years. Survival was unaffected by the number of valves replaced or the type used (27 Starr-Edwards, 32 Björk-Shiley, 8 Lillehei-Kaster, and 4 porcine xenografts). Complications were common: 3 deaths were related to anticoagulation and 1 was due to a systemic embolus. Six patients required permanent pacing. There was a very high incidence of thrombosis of the prosthetic tricuspid valve. Twenty percent of the tilting disc valves thrombosed, compared with 4% of the Starr-Edwards valves (p less than 0.05). Symptoms of thrombosis were usually insidious, and its diagnosis was often delayed. There was a continuing risk of this complication, and presentation occurred up to 12 years after the original operation. Thrombolytic therapy with streptokinase was successful in 1 of 2 patients. Replacement of the thrombosed prosthetic valves was carried out without mortality in 8 patients.

Adult↗
PubMed1987

Degree of reversibility of left ventricular systolic dysfunction after aortic valve replacement for isolated aortic valve stenosis.

To determine whether a low preoperative left ventricular (LV) ejection fraction (EF) returns to normal late after aortic valve replacement for aortic stenosis, 42 patients with critical aortic stenosis (valve area 0.7 cm2 or less), LV systolic dysfunction (EF 0.45 or less), angiographically normal coronary arteries, and no other significant valvular disease were studied at 10 to 84 months (mean 41 +/- 21) postoperatively. All patients survived aortic valve replacement and were discharged clinically improved. There were 4 late deaths; these patients were older (79 +/- 6 vs 64 +/- 13 years, p = 0.007) and had lower preoperative mean valve gradients (51 +/- 6 vs 68 +/- 23 mm Hg, p = 0.003) than late survivors. Of 23 survivors who returned for follow-up radionuclide angiography and Doppler echocardiography, 21 were asymptomatic. EF returned to normal (0.50 or more) in 14 patients (group 1) and remained low in 9 patients (group 2). Doppler peak prosthetic valve gradient was 24 +/- 8 mm Hg in group 1 and 25 +/- 10 mm Hg in group 2 (difference not significant). Six of the 9 patients in group 2 underwent early postoperative radionuclide imaging, and LVEF was normal in 4 (0.65 +/- 0.14 early vs 0.41 +/- 0.06 late, p = 0.02). Of 77 preoperative and intraoperative variables analyzed, only paroxysmal nocturnal dyspnea (0 of 14 vs 4 of 9, p = 0.01) distinguished group 1 from group 2. Thus, LVEF does not always normalize after aortic valve replacement for AS, implying impaired myocardial contractility.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1995

Double-valve replacement with Medtronic-Hall or St. Jude valve.

To define better the performance of the bileaflet St. Jude and the tilting-disc Medtronic-Hall valves, we retrospectively analyzed 122 patients (St. Jude, 80 patients; Medtronic-Hall, 42 patients) who received simultaneous aortic and mitral replacement from May 1984 until June 1994. The two groups were not different with respect to preoperative clinical and hemodynamic parameters and New York Heart Association functional class. The hospital mortality and late mortality were not significantly different. Risk analysis identified advanced age and previous myocardial revascularization as predictors of operative death. Follow-up was complete in 96 of 103 hospital survivors (93%) and was similar in both groups. The actuarial survival, linearized rates of valve-related complications, and actuarial freedom from valve-related complications were similar in both cohorts. The presence of coronary artery disease negatively influenced the actuarial survival after simultaneous aortic and mitral valve replacement. Postoperative New York Heart Association functional class was not significantly different in either group. These data indicate that the Medtronic-Hall and St. Jude prostheses are not significantly different with respect to their clinical performance and valve-related complications for simultaneous double-valve replacement.

Aortic Valve↗
PubMed2005

Impact of valve prosthesis-patient mismatch on left ventricular mass regression following aortic valve replacement.

BACKGROUND: Valve prosthesis-patient mismatch is a frequent problem in patients undergoing aortic valve replacement and its main hemodynamic consequence is to generate high transvalvular gradients through normally functioning prosthetic valves. The persistence of high gradients may hinder or delay the regression of left ventricular hypertrophy after aortic valve replacement. METHODS: The aim of the study was to determine the impact of prosthesis-patient mismatch on the postoperative regression of left ventricular mass. Left ventricular mass was measured by Doppler echocardiography in 109 patients undergoing aortic valve replacement with a single type of bioprosthesis (Carpentier-Edwards Perimount) for pure aortic stenosis. Prosthesis-patient mismatch was defined as a projected indexed effective orifice area less than 0.90 cm2/m2. On this basis, 58/109 (53.2%) patients had prosthesis-patient mismatch. RESULTS: There was a good correlation (r = 0.61, p < 0.001) between the postoperative mean transprosthetic gradient and the projected indexed effective orifice area. The absolute and relative left ventricular mass regression was significantly (p = 0.002 and p = 0.01, respectively) lower in patients with prosthesis-patient mismatch (-48 +/- 47 g, -17% +/- 16%) compared to those with no prosthesis-patient mismatch (-77 +/- 49 g, -24% +/- 14%). In multivariate analysis, a larger projected indexed effective orifice area, female gender and a higher preoperative left ventricular mass are independent predictors of greater left ventricular mass regression. CONCLUSIONS: This study shows that in patients with pure aortic stenosis prosthesis-patient mismatch is associated with lesser regression of left ventricular hypertrophy after aortic valve replacement. These findings may have important clinical implications given that prosthesis-patient mismatch is frequent in these patients.

Aged↗
PubMed2004

Early failure of a tricuspid valve replacement with a mitral valve homograft in a heart transplant recipient.

A 24-year-old woman experienced severe tricuspid valve regurgitation 6 years after heart transplantation. Tricuspid valve replacement was performed using a cryopreserved mitral valve homograft. Severe tricuspid valve regurgitation recurred within 4 months, associated with an increase in the panel reactive antibody titers from zero to 72%. Tricuspid valve replacement was repeated with a porcine bioprosthesis with excellent recovery and function for >2 years. The mitral valve homograft displayed inflammatory features consistent with humoral immune-mediated destruction.

Adult↗
PubMed2002

Patient prosthesis mismatch is rare after aortic valve replacement: valve size may be irrelevant.

BACKGROUND: Although small valve size and patient-prosthesis mismatch are both considered to decrease long-term survival, little direct evidence exists to support this hypothesis. METHODS: To assess the prevalence of patient-prosthesis mismatch and the influence of small valve size on survival, we prospectively studied 1,129 consecutive patients undergoing aortic valve replacement between 1990 and 2000. Mean and peak gradients and indexed effective orifice area were measured by transthoracic echocardiography postoperatively (3 months to 10 years). Abnormal postoperative gradients were defined as those patients with mean or peak gradient above the 90th percentile (mean gradient > or = 21 or peak gradient > or = 38 mm Hg). Patient-prosthesis mismatch was defined as those patients with indexed effective orifice area below the 10th percentile (< 0.60 cm2/m2). RESULTS: A multivariable analysis identified internal diameter of the implanted valve as the only independent predictor of abnormal gradients postoperatively. However, there was no significant difference in actuarial survival between normal and abnormal gradient groups (7 years: 91.2% +/- 1.5% versus 95.0% +/- 2.2%; p = 0.48). Freedom from New York Heart Association class III or IV (7 years: 74.5% +/- 3.1% versus 74.6% +/- 6.2%; p = 0.66) and left ventricular mass index were not different between normal and abnormal gradient groups. Patients with and without patient-prosthesis mismatch were similar with respect to postoperative left ventricular mass index, 7-year survival (95.1% +/- 1.3% versus 94.7% +/- 3.0%; p = 0.54), and 7-year freedom from New York Heart Association class III or IV (79.3% +/- 6.6% versus 74.5% +/- 2.5%; p = 0.40). In patients with patient-prosthesis mismatch and abnormal gradients, the majority had prosthesis dysfunction owing to degeneration. CONCLUSIONS: Severe patient-prosthesis mismatch is rare after aortic valve replacement. Patient-prosthesis mismatch, abnormal gradient, and the size of valve implanted do not influence left ventricular mass index or intermediate-term survival.

Adult↗
PubMed1982

Aortic valve replacement with Starr-Edwards valves over 14 years.

Three hundred thirteen patients underwent aortic valve replacement with 319 Starr-Edwards caged-ball prostheses and have been followed for 1 to 14 years. Hospital mortality (24.8%) and first-year mortality (4.8%) suggest that this is a high-risk group. Overall postoperative patients survival was 37.1%, with 18.8% free from any event, at 14 years. Thromboembolism was the most significant single event (a probability of 18.7% at 14 years), and the Series 2300/2320 valves were associated with a probability of hemolysis of nearly 80% over 13 years. Patients who underwent valve replacement before 1973 had a significantly greater probability of late death (31.1%) and of complications (47.1%) during the first 5 years. Those patients undergoing replacement after 1973 had a significantly greater probability of thromboembolic episodes (15.4%). Starr-Edwards cage-ball prosthesis provide an acceptable valve replacement for high-risk patients. However, the overall complication rate of 81.2% over 14 years, compared with 78% for homograft valves for the same period, does not support the adoption of this prosthesis as the valve of first choice at this hospital.

Actuarial Analysis↗
PubMed1985

The results of valve replacement for mitral valve prolapse.

Between January, 1975, and December, 1982, 33 patients underwent mitral valve replacement for mitral valve prolapse secondary to myxomatous degeneration. The majority were in the seventh decade of life (median age, 62 years), and all were seen with symptoms of mitral regurgitation. Echocardiography was more accurate in making the diagnosis of mitral valve prolapse more often (75%) than angiography (66%). Thirty-eight percent of the patients who underwent cineangiography had concomitant coronary artery disease and had coronary artery bypass grafting as well as mitral valve replacement. There was 1 operative death, an operative mortality of 3%. There were 6 late deaths, a late mortality of 18%. Of the 26 long-term survivors, 23 (88%) were in New York Heart Association Functional Class I and 3 (12%) were in Class II. The average length of follow-up was 33.25 months, and the 5-year actuarial survival was 76%. There was only one incident of thromboembolism (3%). Short-term and long-term survival were not related to the severity of mitral regurgitation but to the status of the left ventricle and the overall condition of the patient. These data suggest that older patients with severe mitral regurgitation secondary to mitral valve prolapse can undergo valve replacement with low operative mortality and gratifying long-term results.

Actuarial Analysis↗
PubMed1987

Disc immobilization of Björk-Shiley and Medtronic Hall valves during and immediately after valve replacement.

During the last fourteen years, 377 unileaflet tilting-disc prosthetic valves (Björk-Shiley and Medtronic Hall) have been used for single or multiple valve replacements with and without concomitant coronary artery by-pass grafting. In the past five years, five instances of disc immobilization (three in the mitral and two in the aortic position) occurred either at the time of weaning from cardiopulmonary bypass or immediately thereafter. When the implanted site of the prosthetic valve was the mitral position, reexploration in 2 patients revealed chordal remnants in the subannular area stuck between the disc occluder and the valve ring, thereby immobilizing the disc. In the third instance, the free movement of the disc was impeded by the left ventricular myocardium. In the aortic position, an unraveled suture impacted between the disc occluder and the valve ring immobilized the disc in 1 patient. In the other patient, the cause of the malfunction could not be determined at the time of reexploration. The 1 death among these 5 patients was directly related to the malfunction of the prosthesis. The mechanism, recognition, treatment, and prevention of this catastrophic malfunction of tilting-disc valves are discussed.

Adult↗
PubMed1988

Incidence of primary tissue valve failure in porcine bioprosthetic heart valves.

This report provides retrospective follow-up data on 324 consecutive patients who received a Hancock-I porcine valve in the aortic or the mitral position, or in both positions, between June, 1974, and December, 1976. This analysis included 319 valves (193 mitral, 126 aortic) available for study of the incidence of primary tissue valve failure after 10 to 12.5 years of follow-up. Of the 319 prostheses at risk, 114 instances of primary tissue valve failure occurred. Seventy-three of the failed valves were in the mitral position, and 41 were in the aortic position. The calculated actuarial probability of freedom from primary tissue valve failure was 52 +/- 5% for the mitral and 58 +/- 6% for the aortic prostheses at 12.5 years of follow-up. For patients older than 40 years at the time of operation, the rate of freedom from primary failure was 68 +/- 8% and 55 +/- 6% for aortic and mitral prostheses, respectively, at 12.5 years. Comparison of both actuarial curves disclosed no meaningful difference. However, a tendency toward greater failure rate was observed in the mitral prosthesis group.

Adolescent↗
PubMed1998

Tricuspid valve replacement: UK Heart Valve Registry mid-term results comparing mechanical and biological prostheses.

BACKGROUND: Little is known of time-related outcome and comparative performance of biological and mechanical prostheses following tricuspid valve replacement (TVR). METHODS: A retrospective UK Heart Valve Registry study (Jan 1, 1986 to June 30, 1997) identified 425 patients who underwent TVR. Two-hundred twenty-five (52.9%) received biological and 200 (47.1%) received mechanical valves. One-hundred sixty (38%), 158, and 76 had isolated, double, and triple valve replacements, respectively. The follow-up was 96% complete with a total of 1,585 patient-years. RESULTS: Thirty-day mortality for TVR was 17.3% (73 deaths). One-, 5-, and 10-year survival rates were 72.2%, 59.9%, and 42.9%, respectively. Year of operation (p = 0.04), age (p = 0.04), and number of valves implanted (p = 0.0 3) predicted overall mortality. Age (p<0.001) and year of operation (p = 0.002) predicted overall survival. Thirty-day mortality for biological and mechanical prostheses was 18.8% and 15.6%, respectively. One-, 5-, and 10-year survival rates were 70.5%, 61.5%, and 47.7% for biological and 74.0%, 57.9%, and 33.9% for mechanical prostheses, respectively. Freedom from reoperation at 1 and 10 years was 98.7% and 97.4%. Freedom from death or reoperation was 71.2% at 1 year and 41.9% at 10 years. None of the above outcomes was significantly different between the type of valve prostheses. CONCLUSIONS: TVR carries a high 30-day mortality and a poor longer term survival. No superiority could be identified for biological or mechanical prostheses in the tricuspid position for either survival or reoperation.

Bioprosthesis↗
PubMed2000

Exposure of the mitral valve by transecting the ascending aorta during aortic and mitral valve replacement.

Combined aortic and mitral valve operations are still considered major cardiac surgical procedures. The duration of aortic cross-clamping and cardiopulmonary bypass is longer, which increases morbidity and mortality for these combined, complicated operations. Aortic valve exposure is generally satisfactory, but mitral valve exposure may be difficult and add to the length of the aortic cross-clamping time. We have exposed the mitral valve by transecting the ascending aorta, and retracting both ends apart, to give direct access through the dome of the left atrium in 7 patients. This approach gave good exposure and did not increase the risk of complications. Exposure of the mitral valve through the left atrium using a superior approach, by transecting the ascending aorta, is a good option for patients with multiple cardiac conditions who are undergoing combined aortic and mitral valve operations.

Aorta↗
PubMed1997

Guidelines for management of left-sided prosthetic valve thrombosis: a role for thrombolytic therapy. Consensus Conference on Prosthetic Valve Thrombosis.

OBJECTIVES: We sought to form a consensus recommendation for management of prosthetic valve thrombosis (PVT) from previous case and uncontrolled reports from a consensus of international specialists. BACKGROUND: PVT and thromboembolism relate to inadequate anticoagulation and valve type and location. PVT is suspected by history (dyspnea) and auscultation (muffled valve sounds or new murmurs) and confirmed by Doppler echocardiography showing a marked valve gradient. METHODS: A consensus conference was held to recommend management of left-sided PVT. RESULTS: Transesophageal Doppler echocardiography is used to visualize abnormal leaflet motion and the size, location and mobility of thrombus. Thrombolysis is used for high risk surgical candidates with left-sided PVT (New York Heart Association functional class III or IV) because cerebral thromboembolism may occur in 12% of patients. Duration of thrombolysis depends on resolution of pressure gradients and valve areas to near normal by Doppler echocardiography performed every few hours. Lysis is stopped after 72 or 24 h if there is no hemodynamic improvement (operation indicated). Heparin infusion with frequent measurement of activated partial thromboplastin time (aPTT) begins when aPTT is more than twice control levels and can be converted to warfarin (international normalized ratio [INR] 2.5 to 3.5) plus aspirin (81 to 100 mg/day). Patients in functional class I or II have lower surgical mortality, and those with large immobile thrombi on the prosthetic valve or left atrium have responded to endogenous lysis with combined subcutaneous heparin every 12 h (aPTT 55 to 80 s) plus warfarin (INR 2.5 to 3.5) for 1 to 6 months. Operation is advised for nonresponders or patients with mobile thrombi. CONCLUSIONS: Thrombolysis, followed by heparin, warfarin and aspirin, is advised for high risk surgical candidates with left-sided PVT.

Aortic Valve↗
PubMedDate not supplied

Early in vivo hemodynamic results after aortic valve replacement with the St Jude Medical Regent mechanical heart valve in patients with pure aortic stenosis.

BACKGROUND: The St Jude Medical Regent is a new-generation mechanical heart valve that represents a design evolution of the St Jude Hemodynamic Plus Series (HP). The purpose of this study was to evaluate early "in vivo" hemodynamic performance of the Regent valve in patients with aortic stenosis. METHODS: Between March 2000 and December 2001, 32 patients (mean age 59.9 +/- 5.9,56.3% male) with pure aortic stenosis received a Regent mechanical prosthesis in the aortic position. Hemodynamic performance was assessed by Doppler echocardiography at discharge, two months, six months, and one year by calculating peak transprosthetic velocity (Vmax), mean (MG) and peak (PG) transprosthetic gradients, effective orifice area index (EOAI), left ventricular mass index (LVMI), and degree of aortic regurgitation. RESULTS: A significant reduction in mean and peak transaortic gradients (p < 0.001) and a significant increase in EOAI (p < 0.001) over time followed valve replacement, and a bivariate analysis of variance (ANOVA) failed to demonstrate statistical differences by valve size over time (p = ns). A significant reduction in left ventricular hypertrophy occurred over time (p < 0.001) in all valve sizes (p = ns between groups): baseline LVMI was 221 +/- 57 g/cm2; it decreased by 30 g/cm2 (p < 0.001) at discharge. LVMI decreased from 191 +/- 54 g/cm2 to 161 +/- 41 g/cm2 (p < 0.001) from discharge to two months. Further reductions were not significant. At the six-month follow-up no patient in our cohort exhibited moderate or severe aortic regurgitation at Doppler echocardiography. CONCLUSIONS: Early results with the St Jude Medical Regent valve have been satisfactory. Further assessments are necessary to confirm these results.

Aged↗
PubMed2006

Stentless mitral valve implantation in comparison to conventional mitral valve repair or replacement at five years.

OBJECTIVE: A chordally supported stentless mitral valve (SMV) may be a suitable prosthesis for patients with severe degenerative mitral valve disease. We analyzed the five-year results and compared them with results after conventional mitral valve repair or replacement. METHODS: 155 patients, operated on since August 1997, were evaluated. 53 patients (ages, 68 +/- 8 years, 37 female, valve repair not feasible) received a SMV (Quattro), 51 patients (69 +/- 9 years, 32 female) had mitral valve repair (MVR) and 51 patients (66 +/- 9 years, 32 female) had a conventional mitral valve replacement (MVP). There were no significant differences with respect to preoperative NYHA functional class, left ventricular ejection fraction, cardiac index and surgical risk, according to the EuroSCORE. Mean follow-up is 64 +/- 18 (21-89) months. RESULTS: Surgery was performed using a median sternotomy (32 [SMV]/20 [MVR]/34 [MVP]) or a lateral mini-thoracotomy 21/31/17 approach. The SMV was safely attached to the papillary muscles. In-hospital mortality was 1, 2 and 4 respectively; re-operation was required in 6, 2 and 3 patients. Five-year survival rate was 80.6 +/- 4.4 % (SMV), 80.2 +/- 5.6 % (CMV) and 82.6 +/- 5.6 % (MVP), p = n.s. After hospital discharge, there was no significant difference in mortality in comparison to an age-matched control population. Echocardiography revealed acceptable SMV hemodynamics with preservation of left ventricular function. CONCLUSION: Midterm results after SMV implantation are comparable to conventional approaches. Complete preservation of the annulo-ventricular continuity is advantageous and close to physiologic hemodynamics can be achieved. Long term follow-up is required.

Aged↗
PubMed1986

Thromboembolism in patients with prosthetic heart valves. An adequately controlled intense anticoagulant therapy and its influence on the occurrence of thromboembolism in relation to valve type.

This study was designed to evaluate the efficacy of carefully controlled treatment with oral anticoagulants in patients with different mechanical heart valve prostheses. One hundred eighty-one patients with various types of prosthetic valves (mitral 89, aortic 87, combined 5) received oral anticoagulation aiming at Thrombotest (TT) values between 5% and 12%. Median follow-up was 46 months; 80.8% of all TT determinations were below 12%. The thromboembolic rate was 0.25%/year in patients with aortic valve replacement (AVR) and 4.87%/year in patients with mitral valve replacement (MVR). There was a strikingly lower incidence of thromboembolism with newer types of valves (Björk-Shiley convex-concave) in the mitral position under exactly the same intensity and stability of anticoagulant treatment. Clinically overt valve occlusion could be almost completely prevented (0.12%/year) in prostheses at both sites. Severe hemorrhage occurred at a rate of 1.71%/year and fatal bleeding at a rate of 0.37%/year. Our results indicate that carefully controlled anticoagulation is effective in the reduction of thromboembolic complications at a reasonable risk of bleeding.

4-Hydroxycoumarins↗