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At least 1,099 records · Page 61Linked to original sources
PubMed1993

Multiple organ failure after mitral valve repair with intravascular hemolysis and its recovery due to mitral valve replacement.

We present a patient with evidence of severe intravascular hemolysis after mitral valve repair, an established method for the surgical treatment of mitral valve disease to avoid prosthesis related complications. The coincidence of this uncommon complication with hemodynamic instability due to pre-existing myocardial dysfunction and Gram-negative pneumonia promoted the development of simultaneous dysfunction of liver, kidney and the cardio-respiratory system. Elimination of the source of hemolysis by re-operation with mitral valve replacement on the ninth postoperative day allowed prompt recovery from severe organ dysfunction. Free hemoglobin may have perpetuated progressive organ failure in our patient.

Adult↗
PubMed1987

Fatal hemolysis due to unidentified causes following mitral valve replacement with bileaflet tilting disc valve prosthesis.

Fatal hemolysis after mitral valve replacement with the St. Jude bileaflet tilting prosthesis is reported in two patients. Although one underwent re-replacement of the valve, both died from multiple organ failure and acute renal failure, respectively. Scanning electron microscopy revealed microthrombi adherent to a leaflet in one and irregular leaflet surfaces in the other. Such defects are rare but are possible causes of hemolysis in patients with the St. Jude mitral valve prosthesis.

Acute Kidney Injury↗
PubMed2003

A case in which biventricular assist device support was required after aortic valve replacement with a bioprosthetic valve.

We report the case of a 45-year-old man with severe aortic regurgitation. The patient underwent aortic valve replacement with a bioprosthetic valve, but was unable to be weaned from cardiopulmonary bypass (CPB). Intraoperative coronary angiography revealed stenosis of the right coronary orifice, so an intra-aortic balloon pump was inserted and coronary artery bypass grafting to the right coronary artery was conducted; however, weaning from CPB again failed. Left ventricular assist using a Gyro centrifugal pump was performed between the left atrium and left femoral artery, along with right ventricular assist using a Nikkiso centrifugal pump between the right atrium and pulmonary artery. Flow rates averaged from 2.0 to 2.8 l/min for the left-side ventricular assist device (VAD) and 2.1-3.8 l/min for the right-side VAD. The bypass rate reached approximately 70% at maximum. No thromboembolic events were documented during VAD support. The patient underwent explantation of VADs on postoperative day 4. No thrombus was identified on the bioprosthetic aortic valve by transesophageal echocardiography. The left-side pump displayed no thrombus, while the right-side pump had a small thrombus at the shaft. The patient was discharged from the hospital and was alive as of 2 year postoperatively. To the best of our knowledge, no clinical study has yet compared the antithrombotic properties of two centrifugal pumps in one patient where mechanical support was performed for the same duration and flow rate.

Aortic Valve↗
PubMed1981

Quantification of valve regurgitation by radionuclide angiography before and after valve replacement surgery.

Radionuclide gated cardiac blood pool imaging was used to quantify the severity of valve regurgitation in 20 patients, by calculating the ratio of left ventricular to right ventricular stroke counts (end-diastolic minus end-systolic counts in right and left ventricular regions of interest). This ratio (the stroke index ratio) was substantially higher in patients with aortic and mitral regurgitation (3.91 +/- 1.45) than in a control group of 10 patients without regurgitation (1.32 +/- 0.15), p less than 0.001. The stroke index ratio correlated closely (r = 0.947) with measurements of regurgitant fraction derived from simultaneous determinations of total and forward stroke volumes during cardiac catheterization. After aortic and mitral valve replacement in 18 patients, the stroke index ratio decreased from 4.03 +/- 1.46 to 1.38 +/- 0.23 (p less than 0.001), a value not significantly different from that observed in patients without regurgitation. All three patients with residual postoperative regurgitation had a stroke index ratio greater than 2 standard deviations above the mean values for the control group (greater than 1.62), whereas the remaining 15 patients, who had no evidence of regurgitation, had values within the normal range. Therefore, radionuclide gated blood pool scanning provides a noninvasive method of quantifying valve regurgitation and assessing the results of medical or surgical interventions.

Adult↗
PubMed1987

Echocardiographic and hemodynamic correlates of diastolic closure of mitral valve and diastolic opening of aortic valve in severe aortic regurgitation.

Acute severe aortic regurgitation (AR) is characterized by a steep increase in left ventricular end-diastolic pressure, exceeding left atrial pressure and occasionally equilibrating with aortic diastolic pressure. These pressure phenomena correlate with the M-mode echocardiographic (echo) findings of diastolic closure of the mitral valve (DCMV) and diastolic opening of the aortic valve (DOAV). Six men, aged 23 to 48 years, with recent-onset, severe AR were evaluated by M-mode echo and pressures at cardiac catheterization. DCMV was seen in all 6 patients and DOAV in 4. Near-constant time intervals from the preceding R wave of the electrocardiogram to DCMV and DOAV were seen, even in 3 patients with varying RR intervals (1 with atrial fibrillation and 2 with asynchronous and demand atrial pacing). When the RR intervals were shorter than these intervals, DCMV and DOAV did not occur. Increasing the heart rate in the 2 patients by atrial pacing resulted in a marked decrease in left ventricular end-diastolic pressure. In conclusion, DCMV and DOAV have a near constant relation to the preceding R wave of the electrocardiogram, DCMV with competence of the mitral valve must be present for DOAV to occur, DOAV indicates that the diastolic blood pressure equals left ventricular end-diastolic pressure, and heart rate is an important factor influencing the hemodynamic and echocardiographic parameters in recent-onset, severe AR.

Adult↗
PubMed2006

Frequency of atrial fibrillation in patients having mitral valve repair or replacement for pure mitral regurgitation secondary to mitral valve prolapse.

Relatively little attention has been paid to the frequency of atrial fibrillation (AF) in patients with mitral regurgitation (MR) secondary to mitral valve prolapse (MVP). We reviewed clinical, electrocardiographic, echocardiographic, hemodynamic, and angiographic findings in 246 patients aged 21 to 84 years (mean 61) (66% men) who had mitral valve repair or replacement for MR secondary to MVP. Immediately before the mitral operation by electrocardiogram, only 37 patients (15%) had AF and the other 209 patients were in sinus rhythm. Of the latter, 32 had had a history of AF that had reverted to sinus rhythm spontaneously or with antiarrhythmic therapy. Thus, a total of 69 patients (28%) had AF at some time. In conclusion, the frequency of AF in patients with MR secondary to MVP and sick enough to warrant a mitral valve operation have a relatively low frequency of AF (persistent in 15%, paroxysmal in another 13%), percentages considerably lower than that seen in patients with mitral stenosis just before a mitral commissurotomy or replacement.

Adult↗
PubMed1999

Early valve failure after aortic valve-sparing root reconstruction.

Aortic valve-sparing root reconstructive surgery has been widely adopted to improve the patient's quality of life. We experienced a patient who required reoperation for progressive aortic regurgitation 17 months after the initial operation of valve-sparing root reconstruction with the reimplantation method in acute aortic dissection. In this study, we were concerned with valve durability because of the absence of sinuses of Valsalva in the new aortic root and the need for careful follow-up after this procedure.

Aortic Valve↗
PubMed2002

Creating a bicuspid valve from the aortic wall: a new surgical approach on aortic valve disease (in vitro study).

We described a new technique (called 'bicuspidization'), which is performed by using autogenous material, without replacement of the aortic valves for the surgical treatment of aortic stenosis and/or insufficiency and tested it in in vitro sheep model. Different stress conditions were simulated by applying three different flow patterns (hemodynamic challenge tests) successively by using a centrifugal pump. It was demonstrated that the competency of the new bicuspid valves was excellent (zero insufficiency). There was a 10-11 mm Hg-increase on trans-valvular gradient comparing the normal hearts. The autogenous bicuspid valve has not blocked the way of the coronary flow in the closed position.

Animals↗
PubMed1995

The valve choice in tricuspid valve replacement: 25 years of experience.

This study reviews 146 consecutive patients who underwent tricuspid valve replacement (TVR) with 69 bioprostheses (porcine and bovine pericardial) and 77 mechanical ball, disc or bileaflet valves between 1967 and 1987. The mean age was 51.4 +/- 12.1 years. Preoperatively, 97% were in New York Heart Association (NYHA) functional class III or more and over 40% had undergone previous cardiac surgery. Hospital mortality was high (16.1%). Incremental risk factors for hospital death were preoperative icterus (P < 0.01), hepatomegaly (P = 0.02), NYHA functional class IV (P = 0.02) and male sex (P = 0.04) (univariate analysis). Ninety-eight percent of the hospital survivors were followed up for a mean of 92 months. Cumulative follow-up added up to 955 patient-years. There were 70 late deaths. The actuarial survival rate was 74% at 60 months and less than 25% at 14 years. Incremental risk factors for late death indicated by univariate analysis were the type of tricuspid prosthesis (Smel-off-Cutter and Kay-Shiley prostheses) (P = 0.04), the type of operative myocardial protection (normothermia and coronary perfusion) (P = 0.05) and preoperative NYHA functional class IV (P = 0.05). We conclude that TVR carries a high operative risk and poor long-term survival, both influenced by preoperative and perioperative variables. Bearing in mind the poor prognosis for TVR, we prefer a large-sized bioprosthesis, in view of its initial good durability and low risk of valve-related events. However, in patients with good life expectancy, a bileaflet mechanical prosthesis may be an acceptable alternative.

Actuarial Analysis↗
PubMed1993

Complete prosthetic valve thrombosis despite several thrombolytic treatments after tricuspid valve replacement.

We discuss the case of a 50-year-old man who underwent tricuspid valve replacement with a mechanical prosthesis (Duromedics) due to traumatic tricuspid insufficiency following a blunt chest trauma fifteen years previously. Despite correct anticoagulation therapy several events of prosthetic valve thrombosis occurred in the following years. The patient was treated four times by thrombolytic therapy. Finally, seven years after the initial operation the mechanical valve was replaced by a Carpentier-Edwards bioprosthesis because of complete blockage.

Heart Valve Prosthesis↗
PubMed2006

Prediction of valve prosthesis-patient mismatch prior to aortic valve replacement: which is the best method?

BACKGROUND: To predict the occurrence of valve prosthesis-patient mismatch (VP-PM) after aortic valve replacement (AVR), the surgeon needs to estimate the postoperative effective orifice area index (EOAI). AIM: To compare different methods of predicting VP-PM. METHODS: The effective orifice area (EOA) of 383 patients who had undergone AVR between July 2000 and January 2005 with various aortic valve prostheses was obtained echocardiographically 6 months after the operation. We tested the efficacy of (1) EOAI calculated from the echo data obtained in our own laboratory, (2) indexed geometric orifice area, (3) EOAI estimated from charts provided by prosthesis manufacturers (which are based either on in vitro or on echo data) and (4) EOAI estimated from reference echo data published in the literature to predict VP-PM. RESULTS: Sensitivity and specificity to predict VP-PM were 53% and 83% (method 1), 80% and 53% (charts based on echo data, parts of method 3) and 71% and 67% (method 4) using reference data derived from echocardiographic examinations. The sensitivity of method 2 and of charts based on in vitro data (parts of method 3) to predict VP-PM was 0-17%. The incidence of severe VP-PM could be reduced from 8.7% to 0.8% after the introduction of the systematic estimation of the EOAI at the time of operation (p = 0.003, method 1). CONCLUSIONS: The best method of predicting VP-PM is the use of mean (SD) EOAs derived from echocardiographic examinations, whereas the use of in vitro data or the geometric orifice area is unreliable. After the surgeon's anticipation of VP-PM prior to AVR, the incidence of VP-PM could be reduced.

Aged↗
PubMed2005

Aortic valve replacement and concomitant mitral valve regurgitation in the elderly: impact on survival and functional outcome.

BACKGROUND: The impact of mitral regurgitation (MR) on elderly patients (> or = 70 years) undergoing isolated aortic valve replacement (AVR) is not clearly defined. This study investigates the long-term effects of preoperative, moderate MR on survival and functional outcome in elderly AVR patients. METHODS AND RESULTS: A retrospective review identified 408 consecutive elderly patients who underwent isolated AVR from January 1983 to February 2004. The pathologic etiology of MR was determined on preoperative echocardiogram, and patients were stratified into no/mild MR (Group I; n = 338) versus moderate MR (Group II; n = 70). Follow-up was 95.1% complete. Functional outcome was evaluated using the Short Form-12 questionnaire. On univariate analysis, Groups I and II differed in incidence of previous myocardial infarction (13.9% versus 28.6%; P = 0.004), hyperlipidemia (18.7% versus 33.3%; P = 0.009), and congestive heart failure (50.0% versus 70.0%; P = 0.002). On multivariate analysis, moderate MR was an independent risk factor impacting long-term survival (P = 0.04). Actuarial survival at 1, 5, and 10 years for Group I was 93.8%, 73.3%, and 40.1% versus 92.3%, 58.2%, and 14.6% for Group II (P = 0.04). Available postoperative echocardiograms for Group II (n = 37) demonstrated improvement in MR in 81.8% of functional MR patients. However, MR persisted or worsened in 65.4% of patients with intrinsic mitral valve disease (myxomatous, calcific, or ischemic MR). Functional outcomes showed 77% of Group I versus 78.6% of Group II rated their health as good to excellent post-AVR. CONCLUSIONS: Moderate MR is an independent risk factor impacting long-term survival in elderly patients undergoing AVR. Therefore, patients with intrinsic mitral valve disease should be considered for concomitant MV surgery.

Age Factors↗
PubMed1992

Periaortic hematoma formation leading to aortic valve failure. A complication of homograft placement for second valve surgery.

The aortic homograft has become the replacement valve of choice in the treatment of complicated endocarditis involving native and prosthetic aortic valves. Complications are rare, typically involving chronic leaflet degeneration causing valvular insufficiency or rarely chronic calcific stenosis. We present a case in which functional stenosis of the homograft valve was caused by compression and distortion by blood transmitted directly from the left ventricle into a space between the homograft and an external cavity formed by a Dacron wrap. The latter had been placed to help control suture-line bleeding. This case presentation demonstrates an unusual cause of homograft failure and suggests that wrapping of a homograft conduit by native aorta or an external Dacron wrap is not a substitute for meticulous surgical technique to assure a hemostatic suture line.

Aortic Valve↗
PubMed1975

Aortic valve replacement with the Björk-Shiley tilting disc valve prosthesis. Clinical experiences in 50 cases.

Single aortic valve replacement with the Björk-Shiley tilting disc valve prosthesis has been performed in 50 patients since April 1971. None of the total of six deaths (12.0%) was attributable to malfunction of the prosthesis or to embolic complications. Follow-up examination showed insignificant or moderate prosthetic regurgitation in two patients and moderate paravalvular leakage in one patient. A slight intravascular haemolysis was found in two cases, one of them without marked regurgitation, and a slight reversible cerebral thrombo-embolism in two. Clinical improvement was observed in 43 of the 44 survivors during the 6 to 12 months of follow-up. Objective evidence of improvement was verified by cardiac catheterization following the replacement of aortic valve with the Björk-Shiley tilting disc prosthesis.

Adolescent↗
PubMed1977

Combined aortic and mitral valve replacement with the Björk-Shiley tilting disc valve prosthesis. Early and late results in 75 consecutive patients.

This study evaluates the early and late results of combined aortic and mitral valve replacement with the Björk-Shiley tilting disc valve prosthesis in 75 consecutive patients operated upon during a 6-year-period commencing October 1969. The Delrin disc model Björk-Shiley prosthesis was inserted in the first 20 patients and the pyrolytic carbon disc model in the remainder. The opening angle was increased from 50 degrees to 60 degress and the Teflon sewing ring was designed with two flanges in the pyrolytic carbon disc mitral model. The patient material was characterized by marked cardiomegaly, impaired physical working capacity, hypokinetic central circulation, pulmonary hypertension and a 59% incidence of atrial arrhythmias before operation. Surgery was performed during generalized hypothermia to 30 degrees C and selective coronary perfusion, and the mitral valve was always replaced first. There were no intra-operative deaths, although 7/75 patients (9%) died while in hospital. Twelve patients (16%) died in average 19 (2-59) months postoperatively. Thrombo-embolic complications, which were frequently associated with poor anticoagulation, occurred in 9 patients and were fatal in 4 cases, corresponding to an incidence per patient month of 0.005 and 0.002, respecitvely. This risk was not affected by the type of prosthesis. One patient required operative repair of an aortic paraprosthetic leakage. Clinical improvement was found in 88% of the long-term survivors. The maximal working capacity increased in average 41% over the pre-operative value (p less than 0.001) and cardiac enlargement diminished in average by 22% (p less than 0.001). The incidence of atrial arrhythmias decreased slightly to 48%. Haemolysis was mild and without clinical significance. The actuarial curve indicated a 75% survival rate 3 years after operation.

Adolescent↗
PubMed1979

Successful replacement of the aortic valve, mitral valve and ascending aorta with re-implantation of the coronary arteries.

A 63-year-old man was operated upon with replacement of the aortic valve, mitral valve and ascending aorta with re-implantation of the coronary arteries. A composite graft with a 27 mm Björk-Shiley tilting disc prosthesis was inserted with 3 continuous Prolene sutures in the aortic position. The coronary arteries were thereafter re-implanted in holes made in the graft. A 31 mm Björk-Shiley valve was sutured in the mitral position with about 20 isolated mattress sutures of Ti-Cron. Selective myocardial hypothermia was instituted with Ringer's solution of 4 degrees C. The total perfusion time was 185 min compared with 240 and 275 min in two previously reported, similar cases. We consider that the use of cardioplegia, a composite graft and continuous sutures makes it possible to reduce the operation time in these complex cases. Our patient is in good condition 9 months postoperatively.

Aortic Aneurysm↗
PubMed1994

Mitral valve prosthetic implantation with preservation of native mitral valve apparatus.

To avoid postoperative morbidity and mortality often associated with left ventricular dysfunction after mitral valve replacement (MVR) for chronic mitral insufficiency, reconstruction or preservation of the native mitral valve apparatus may be attempted during mitral prosthetic implantation (MPI). The effects of mitral surgery on heart function, studied with echocardiography and radionuclide angiography, were compared in seven patients with MPI (study group) and five with MVR (control group) who underwent complete preoperative, early postoperative and 3-6 months follow-up examinations. Preoperatively there was significant intergroup difference only in right ventricular ejection fraction measured at radionuclide angiography, which was lower in the MPI group (p < 0.05). At follow-up the MPI group had improved as regards this fraction (p < 0.005) and stroke volume index (p < 0.05). The number of patients with improved NYHA class at follow-up was significantly greater in the MPI group. Our preliminary experience with preservation of the native mitral valve apparatus thus suggests that the method offers haemodynamic advantages for postoperative right ventricular function.

Aged↗
PubMed2000

Superiority of mitral valve replacement with preservation of subvalvular structure to conventional replacement in severe rheumatic mitral valve disease: a modified technique and results of one-year follow up.

BACKGROUND AND AIM OF THE STUDY: Mitral valve replacement with preservation of the subvalvular apparatus (MRVP) has been proven superior to conventional mitral valve replacement (MVR). We devised a simple modified MVRP method in this prospective, randomized study to investigate the clinical effects and one-year follow up echocardiographic results of MVRP compared with MVR in patients with severe rheumatic mitral insufficiency (MI). METHODS: Sixty-eight patients with severe rheumatic MI with or without stenosis were randomized to MVRP (n = 35) and MVR (n = 33) groups. In MVRP patients, the preserved tissue was pulled back posteriorly to the posterior wall of the left ventricle, then plicated and reaffixed to one-fourth of the annular circumference in the posterior annulus, in order to prevent left ventricular outflow tract (LVOT) obstruction. Clinical data including cumulative ventricular arrhythmias and use of inotropes were collected. Echocardiography examination was performed before surgery, and at five days, three months and one year thereafter. RESULTS: There were no preoperative differences patient data. The cross-clamp time was 2.2 min longer in MVRP patients. The one-month mortality rate after surgery was lower in MVRP patients (2.9% versus 15.2%, p = 0.074). Mechanical ventilation and ICU times were shorter in the MVRP group (17.6 versus 24.8 and 52.5 versus 70.6 h, p = 0.001 and 0.1, respectively). There were fewer ventricular arrhythmias and less need for inotropic support in this group. One year follow up echocardiography data showed better preserved left ventricular ejection fraction (LVEF) and better recovery of heart size after MRVP. There was no indication that preserved valvular tissue interfered with mechanical valve function, or caused LVOT obstruction. CONCLUSION: This modified MVRP technique is simple, effective and without risk of LVOT obstruction. In severe rheumatic MI patients the outcome of MVRP is superior to that of conventional MVR in term's of mortality, postoperative care needs, left ventricular function and heart dimensions.

Adult↗