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At least 865 records · Page 48Linked to original sources
PubMed2003

Lower-intensity anticoagulation for mechanical heart valves: a new concept with the ATS bileaflet aortic valve.

BACKGROUND AND AIM OF THE STUDY: The design of the bileaflet ATS mechanical valve incorporates an open pivot at the hinge mechanism. Total washout of blood at the pivot area seen using three-dimensional computational fluid dynamics modeling may make the valve less vulnerable for clot formation in patients without major thromboembolic risk factors. METHODS: Between January 1993 and June 1999, the ATS valve was implanted in the aortic position in 286 consecutive patients. Patients were allocated prospectively to two groups: group 1 comprised patients in regular sinus rhythm with good left ventricular (LV) function (n = 144); group 2 included patients in non-sinus rhythm and/or with large hypocontractile left ventricles (n = 142). The anticoagulation regime in group 1 was to achieve an INR of 1.5-2.5, rather than to maintain INR strictly at 2.5-3.5 for mechanical valves (as in group 2). RESULTS: Follow up was 99% complete and ranged from 50 to 120 months. Survival (Kaplan-Meier) was respectively 95% and 90% and 90% and 83% at 2 and 5 years in favor of group 1 (p = 0.0055). Multivariate analysis selected advanced age, poor LV function and 'erratic' INR as risk factors for death. Log rank analysis failed to detect any statistical difference in thromboembolism. Bleeding occurred more frequently in group 2 (p = 0.018); independent risk factors for bleeding were the presence of aspirin (p = 0.0164) and advanced age (p = 0.02). CONCLUSION: The excellent group 1 data and outcome encouraged continuation of the low-intensity anticoagulation regime, and should be regarded as a new concept for the treatment of mechanical valve patients.

Aged↗
PubMed1992

Left ventricular mechanics and myocyte function after correction of experimental chronic mitral regurgitation by combined mitral valve replacement and preservation of the native mitral valve apparatus.

BACKGROUND: Contractile function improves after correction of experimental mitral regurgitation, but ejection performance becomes depressed when mitral valve replacement involves chordal transection. A role for chordal transection in producing the depressed ejection performance was suspected but uncertain. Therefore, in this study, we tested two specific hypotheses: 1) that contractile function would improve and, in conjunction with chordal preservation, would allow for preserved ejection performance and 2) that improved left ventricular contractile function after surgery would be reflected in the function of myocytes isolated from the affected left ventricles. METHODS AND RESULTS: We examined ventricular contractile function and ejection performance and isolated myocyte function after correction of experimental mitral regurgitation (chordal rupture) with mitral valve replacement that involved chordal preservation. After 3 months of chronic mitral regurgitation, the average regurgitant fraction of seven dogs was 0.77 +/- 0.04. End-diastolic volume had increased from 79 +/- 5 to 132 +/- 10 cm3 (p < 0.05). At that time, all indexes of left ventricular contractile function were depressed. Three months after mitral valve replacement with chordal preservation, end-diastolic volume fell to 100 +/- 4 cm3 (p < 0.05). At this time, all indexes of contractile function had returned to normal. End-systolic stress and ejection fraction after mitral valve replacement were similar to their baseline levels. Viscosity-velocity curves (analogous to force-velocity curves) of myocytes isolated from the affected left ventricles were similar to those of myocytes isolated from normal left ventricles. CONCLUSIONS: We conclude that mitral valve replacement with chordal preservation allows ventricular contractile function to return to normal. Normal global ventricular function, in turn, is associated with normal function of the individual myocytes that compose the left ventricular chamber. Further, chordal preservation allowed for loading and ejection performance to return to premorbid levels.

Animals↗
PubMed2006

[Case in which landiolol hydrochloride improved left ventricular outflow tract obstruction with systolic anterior motion of the mitral valve following mitral valve plasty].

We report a case of left ventricular outflow tract (LVOT) obstruction caused by systolic anterior motion of the mitral valve (SAM) following mitral valve plasity (MVP). A 65-year-old man underwent mitral valve plasty for grade III mitral valve regurgitation. The plasty was done smoothly and the patient was weaned from cardiopulmonary bypass successfully with continuous dobutamine infusion. However, about 30 minutes after the weaning, severe cardiovascular collapse developed. Inotropic agent, such as dobutamine, ephedrine, or calcium hydrochloride was not effective. Trans-esophageal echocardiography (TEE) showed severe mitral valve regurgitation with LVOT obstruction due to SAM. The collapse was successfully treated with volume loading and a small amount of a beta1-adrenergic antagonist, landiolol hydrochloride. We conclude that acute LVOT obstruction with SAM could develop following MVP. TEE was a much useful tool for early diagnosis and landiolol hydrochloride would be a notable agent for nonsurgical treatment of LVOT obstruction with SAM.

Adrenergic beta-Antagonists↗
PubMed1989

[Double orifice mitral valve associated with bicuspid aortic valve].

A 63-year-old man with double orifice mitral valve (DOMV) and bicuspid aortic valve was reported. Preoperative echocardiography showed prolapse of the posterior leaflet and mitral regurgitation but was unable to show the existence of the duplication of the mitral valve. He underwent aortic and mitral valve replacement and did well after surgery. DOMV is a rare congenital malformation, and DOMV associated with bicuspid aortic valve is the first reported case in Japan.

Abnormalities, Multiple↗
PubMed1988

[Regression of myocardial hypertrophy in aortic valve disease following aortic valve replacement].

In patients with aortic valve disease successful valve replacement leads to a significant decrease in left ventricular angiographic mass, which 14-15 months postoperatively ranges between 31 and 37% of the preoperative value. Postoperative normalization of angiographic mass occurs in 2/3 of the patients with aortic stenosis and in 1/3 of the patients with aortic insufficiency. The degree of preoperative hypertrophy determines whether angiographic mass does or does not normalize after valve replacement. In patients with aortic stenosis and combined lesions, left ventricular end-diastolic wall thickness decreases postoperatively and remains unchanged in the patients with aortic insufficiency. Muscle fiber diameter decreases significantly in the first two years after valve replacement and thereafter remains unchanged. The upper limit of normal (20 mu) is not reached. Relative interstitial fibrosis increases early after surgery whereas left ventricular fibrous content remains unchanged during the first two years after valve replacement. Five years postoperatively there was a significant decrease in left ventricular fibrous content both in patients with aortic stenosis and with aortic insufficiency. Hence there appears to be no longer any validity in the earlier concept that a once established interstitial fibrosis in patients with concentric and eccentric hypertrophy is irreversible after removal of the abnormal hemodynamic burden.

Aortic Valve Insufficiency↗
PubMed1988

[Spontaneous course of aortic valve disease and indications for aortic valve replacement].

190 adult patients with aortic valve disease have been followed up after initial cardiac catheterization until death or aortic valve replacement (event-free survival). Neither hemodynamic severity nor symptoms alone were reliable predictors of survival, but the combination of both was very helpful. In the presence of hemodynamically and symptomatically severe aortic stenosis and aortic regurgitation only 40% of patients survived for two years, but patients with hemodynamically severe aortic stenosis but with few or no symptoms had 100% survival at two years and 75% were event free at five years. In hemodynamically severe aortic regurgitation two asymptomatic patients died within the first two years (94% survival at two years) and 65% were event free at five years. In the absence of coronary artery disease there was no mortality within the first two years in moderate or mild stenosis and regurgitation regardless of symptomatic status. Hemodynamically and symptomatically severe aortic stenosis and regurgitation have a very poor prognosis and require immediate valve surgery. Asymptomatic and mildly symptomatic patients with hemodynamically severe aortic stenosis are at low risk and surgical treatment can be postponed until marked symptoms appear without significant risk of sudden death. In severe aortic regurgitation, the decision to perform surgery should depend not only on symptoms but should be considered in patients with few or no symptoms because of the risk of sudden death. In the absence of coronary artery disease, hemodynamically moderate aortic valve disease does not require valve surgery on prognostic grounds.

Adolescent↗
PubMed1985

[Hemolysis in patients with heart valve prostheses. Comparison between Björk-Shiley and Saint-Jude Medical valves].

The problem of haemolysis was studied in 244 patients with one or two prosthetic heart valves: 232 of these patients had normal valve function as assessed by clinical examination, radioscopy and echocardiography; 112 patients had a Bjork-Shiley (BS) prosthesis, 25 in the aortic position (BSA), 71 in the mitral position (BSM) and 16 in both aortic and mitral positions (BSA + M). These patients were operated between July 1979 and January 1981. One hundred and twenty other patients had Saint Jude medical (SJM) prostheses; 48 in the aortic position (SJMA), 44 in the mitral position (SJMM) and 28 in both aortic and mitral positions (SJMM + A). These patients were operated between January 1982 and July 1983. Twelve patients (operated between 1977 and 1984) had prosthetic valve dysfunction confirmed by angiography or anatomically (SJM = 7); BS = 5). The plasma haemoglobin concentration (pHb) was used as the reference: it was measured by spectrophotometry with a sensitivity of 0.5 mg/100 ml. There was no significant difference the SJM and BS groups at surgery (BS: 4.62 mg/100 ml; SJM: 4.31 mg/100 ml). In the absence of prosthetic valve dysfunction, haemolysis was significantly greater (p less than 0.001) in the SJM (8.28 mg/100 ml) than in the BS (3.08 mg/100 ml). No statistical correlation was observed with the severity of cardiac disease, the aortic or mitral position of the prostheses or with the number of prostheses. Haemolysis was subclinical in all cases. When haemodynamically significant prosthetic valve dysfunction was present, haemolysis was inconstant in BS prostheses (2 out of 5 cases) despite major haemodynamic disturbances in all cases.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1978

Aortic valve replacement. A randomized study comparing the Björk-Shiley and Lillehei-Kaster disc valves. Peroperative haemodynamic evaluation and early results.

Three hundred patients were selected at random in order to compare the Björk-Shiley and the Lillehei-Kaster valves in the aortic position. Peroperative haemodynamic evaluations were carried out in 106 cases. The effective orifice area of the valves and the effective area index were calculated. The results indicate that the Björk-Shiley valves utilize the available space in the aortic root about 12% better than the Lillehei-Kaster valves. There were 11 hospital deaths, but none of them were valve related.

Adolescent↗
PubMed1995

[Influence of the valve position on the complications related to pericardial Carpentier-Edwards valve after 8 years].

Between July 1984 and December 1991, 541 Carpentier-Edwards pericardial prostheses were implanted in 536 patients (420 aortic and 121 mitral prostheses). The operative mortality was 2.9% for aortic and 3.3% for mitral valve replacement. All but 8 patients were followed up for an average of 3.9 years, making a total follow-up of 1930 patient-years. There were 61 deaths during follow-up (41 AVR, 20 MVR). The actuarial 8 year survival was 80 +/- 6% for AVR and 74 +/- 10% for MVR. There were 15 deaths related to the prostheses. The probability of absence of valve-related mortality was 97 +/- 3% for AVR and 92 +/- 6% for MVR (NS). The valve-related complications included 15 thromboembolic events (AVR: 12; MVR: 3), 10 endocarditis (AVR: 7; MVR: 3), 8 anticoagulant-related haemorrhages (AVR: 4; MVR: 4), 4 degeneration (AVR: 2; MVR: 2). There were no cases of cusp tear. The probability of absence of thromboembolic events at 8 years was 96 +/- 3% for AVR and 96 +/- 4% for MVR (NS), of absence of endocarditis 97 +/- 2% for AVR and 97 +/- 3% for MVR (NS) and of absence of valve degeneration 99 +/- 1% for AVR and 99 +/- 2% for MVR (NS). These results show that the position of the bioprosthesis had no influence on valve-related morbidity and that pericardium is a satisfactory tissue for the manufacture of mitral bioprostheses.

Actuarial Analysis↗
PubMed1994

[Successful mitral valve replacement in multiple organ failure due to mechanical hemolytic anemia after mitral valve repair: a case report].

An 18-year-old man suffered multiple organ failure due to hemolytic anemia after mitral valve repair. He was admitted with mitral regurgitation (MR) and mitral valve repair was performed. However, after 3 days of the operation, he developed hemolytic anemia and heart murmur. A reoperation of mitral valve replacement was performed because of progressing heart failure with renal and liver dysfunction. The operative findings revealed a rupture in the choldae with dislocation of the C-E ring. The MR flow and dislocated ring are suspected to be the cause of the hemolysis. After the reoperation, the hemolysis and general condition were immediately improved. The indication of this reoperation should be carefully decided. In this case of multiple organ failure following mitral valve repair, reoperation of mitral valve replacement was successful.

Adolescent↗
PubMed1994

[Aortic valve replacement using aortic donor valves of human origin].

OBJECTIVE: To evaluate the experiences of aortic valve replacement with cryopreserved aortic allografts in the subcoronary position. DESIGN: Descriptive clinical study. SETTING: Thorax Centre of Rotterdam University Hospital. METHOD: In the period July 1988-March 1993, 68 patients (45 men and 23 women) with a mean age of 45 years underwent 69 operations. One woman was operated twice. Main criteria for aortic valve replacement by an allograft were age and endocarditis. The pathology leading to aortic valve dysfunction had been: endocarditis (38%), congenital lesions (32%), rheumatic lesions (19%), senile degeneration (7%), paravalvular leakage (3%) and an active autoimmune disease (1%). RESULTS: Hospital mortality was 4%. The mean follow-up was 22 months, with a cumulative follow-up of 126 patient years. One patient died of lung cancer during this period. Six patients needed a second operation (9%); 4 of these were among the first 15 patients operated on. One of these reoperations was necessary to treat a recurrent endocarditis. Only one other late valve-related event took place: a transient ischaemic attack 2 years postoperatively. Ninety-one per cent of the patients with an allograft in situ were in NYHA class I at their last outpatient clinic visit. The other patients were in class II. Pre-cordial color Doppler echocardiography showed no or mild aortic regurgitation in 95% of these patients. The remaining 3 patients had moderate aortic regurgitation. CONCLUSION: Aortic valve replacement with an allograft was performed with low hospital mortality. The expected advantages are greatest in young patients and patients with endocarditis; these patients, therefore, should have priority in allograft allocation.

Adolescent↗
PubMed1993

[Surgical treatment for mitral valve defects with preponderance of mitral stenosis and high pulmonary vascular resistance. Clinical and hemodynamic observations 6 months after valve replacement].

10 patients with isolated or predominant mitral stenosis (mean mitral valve area 0.9 cm) and high preoperative values of pulmonary vascular resistance (mean 7.2 Wood units) were chosen for further hemodynamic postoperation evaluation. The patients had normal function of the aortic valve and no significant stenosis of coronary arteries. Hemodynamic evaluation was done by floating Swan-Ganz catheter preoperatively at rest and 6 months after mitral valve replacement at rest and during bicycle cycloergometer test in the supine position. Significant improvement in NYHA class was noted. Preoperatively 6 patients were in NYHA III class, 4 in NYHA IV class. After mitral valve replacement 4 patients were in class III and 6 in class II. Before mitral valve replacement only 3 patients were able to perform 25 Watt test. After surgery all except one performed at least 25 W. There was a significant decrease of pulmonary vascular resistance from 7.2 +/- 2.2 preoperatively to 3.1 +/- 1.9 Wood units at rest after the operation. Post operation during exercise pulmonary vascular resistance attained 4.2 +/- 1.9 Wood units. These changes were due to a fall in mean pulmonary artery pressure 49 +/- 13 at rest preoperatively to 25 +/- 6 mm Hg (rest) and 43 +/- 14 mm Hg (23 W) postoperatively and a rise in stroke volume index from 24 +/- 7 ml (m2) beat preoperatively to 32 +/- 9 at rest and 33 +/- 6 (25 W) postoperatively. Despite clinical and hemodynamic improvement there was no full recovery of pulmonary hemodynamics.

Adult↗
PubMed1993

Mitral valve anomalies associated with Ebstein's malformation of the tricuspid valve.

The original description of Ebstein's anomaly mentioned a mild deformity of the mitral valve. Reviews of large series of cases with Ebstein's malformation have, however, tended to omit reference to accompanying mitral valve malformations. We have compared the mitral valves in 19 specimens with Ebstein's malformation with those in 30 age-matched controls in order to determine the prevalence and nature of these anomalies. In the Ebstein's group the mitral valve was abnormal in 14 hearts with orificial anomalies in four, leaflet anomalies in 11, cord anomalies in 11 and papillary muscle anomalies in 13. In the control group, five cases showed mild shortening of the tendinous cords. Half of the changes found in the Ebstein's group were of moderate or significant degree suggesting a primary involvement of the mitral valve. In time, dynamic alterations within the left ventricle might become superimposed and contribute to the development of clinically significant lesions.

Adult↗
PubMed1996

[A case of valve thrombosis of CarboMedics prosthesis four years after mitral valve replacement: relationship of anticoagulant therapy to coagulation and fibrinolysis activating factors].

A 50-year-old man experienced acute heart failure four years after initial mitral valve replacement (MVR) for left atrial thrombosis using a CarboMedics prosthesis, despite satisfactory coagulation control with warfarin. After initial MVR, late cardiac tamponade occurred twice and left circumflex branch stenosis was treated with percutaneous transluminal coronary angioplasty (PTCA). Re-MVR with an Edwards-TEKNA valve was performed after echocardiography and cineradiography showed mitral valve thrombosis, with thrombi on both mitral valve leaflets and covering most of the left atrial wall. Post-surgery progress was favorable with warfarin and dipyridamole therapy. After six weeks cardiac catheter revealed complete right external iliac artery occlusion. Cardiac dysfunction and atrial flutter apparently accelerated thrombosis after a common cold activated coagulation. Cardiac tamponade, circumflex branch stenosis, and right external iliac artery occlusion occurred despite satisfactory coagulation control by warfarin. Warfarin suppresses some coagulation factors but cannot always correct hypercoagulability. Two months after re-MVR, coagulation tests showed normal TT, F1 + 2, and D-Dimer but an increase in TAT, suggesting involvement of additional coagulation factors. After artificial valve replacement, therapy should achieve a PT-INR level of 3.0-4.5, with close follow-up using other indices of fibrinolysis and coagulation activity in addition to TT.

Acute Disease↗
PubMed1998

Mitral valve repair: an odyssey to save the valves!

The history of mitral valve repair surgery is an interesting odyssey that has nearly spanned the century. However, since the mid 1970s, both European and North American surgeons have developed and expanded these techniques to where repair of myxomatous valves is now expected by most cardiologists and patients. Preoperative functional assessment is most important to determine the specific needs for repair. Today, transesophageal echocardiography is the standard by which cardiologists and surgeons rely for these data. Herein, both methods of assessment and techniques for repair are detailed. The multidisciplinary approach is emphasized. Risks of surgery are detailed as well as long-term outcomes compared with replacement of the mitral valve. Lastly, surgical results from the 235 patients repair series at the East Carolina University School of Medicine are detailed and discussed. This series showed a 1.8% mortality rate for myxomatous valve patients, with a very low reoperative rate. This compared with a higher mortality rate of 5.6% for the overall group, which emphasizes the increased risk associated with an ischemic etiology. The author provides not only an overview but also tips to surgeons beginning to repair valves.

Cardiac Surgical Procedures↗
PubMed2004

Aneurysm of the mitral valve: a rare complication of aortic valve endocarditis.

A 45-year-old man presented to our hospital with severe dyspnea 4 months after antibiotic treatment for aortic valve endocarditis. Transesophageal echocardiography revealed severe aortic regurgitation and an aneurysm of the anterior leaflet of the mitral valve. In addition to aortic valve replacement, we excised the aneurysm and repaired the anterior leaflet of the mitral valve. Clinical suspicion, appropriate preoperative imaging, and timely surgical intervention are essential to recognize and treat this rare complication of bacterial endocarditis.

Acute Disease↗
PubMedDate not supplied

Left atrial spontaneous echo contrast assessed by TEE in patients with either native mitral valve disease or mitral valve replacement.

The incidence of spontaneous echo contrast in the left atrium, the factors with which it is associated, and its clinical significance were studied in 128 patients with native mitral valve disease or mitral valve replacement. All patients underwent both transesophageal and transthoracic echocardiography. Spontaneous echo contrast was visualized in 42 patients (33%) during transesophageal and in none during transthoracic echocardiography. Patients with spontaneous echo contrast had a significantly larger left atrial diameter (6.1 [1.1] cm vs 4.9 [0.9] cm, p < 0.001) and a greater incidence of both atrial fibrillation (54% vs 4%, p < 0.001) and left atrial thrombi (60% vs 28%, p < 0.01) compared with patients without spontaneous echo contrast. Multivariant analysis confirmed that these factors were independently associated with spontaneous echo contrast (left atrial size, p < 0.001; atrial fibrillation, p < 0.001; left atrial thrombus, p < 0.01). Patients with pure mitral regurgitation did not have any spontaneous echo contrast and anticoagulation did not influence its incidence. Spontaneous echo contrast was the only factor that was associated with a previous history of systemic embolization (history of systemic emboli in 28.6% of patients with spontaneous echo contrast vs 13.9% without spontaneous echo contrast, p < 0.05). In conclusion, spontaneous echo contrast is a common finding in the left atrium of patients with mitral valve disease or mitral valve replacement and represents a marker of increased thromboembolic risk in these patients.

Adult↗
PubMed1997

[Clinical and echocardiographic evaluation of the Medtronic-Hall 20A valve in the aortic position in patients with small aortic annulus: comparison with the 21 mmSJM valve].

We compared the results of Medtronic-Hall 20A aortic valve (MH20A) replacement with those of 21 mm SJM valve (SJM21A) replacement. The subjects were 17 patients who underwent aortic valve replacement with MH20A. The mean age was 65.4 +/- 8.8 years in the MH20A group. The average body surface area in the MH20A group was 1.37 +/- 0.08 m2, which was significantly smaller than in the SJM21A group (1.55 +/- 0.09 m2). The postoperative follow-up period was 51 months at maximum and 20 months on average. There was one hospital death and two late deaths in the MH20A group. The other patients were categorized NYHA I classification. The trans-valvular peak pressure gradient soon after surgery was 21 +/- 9.3 mmHg in the MH20A group, and 23.9 +/- 8.8 mmHg in the SJM21A group. Preoperative and late postoperative echocardiograms demonstrated significant decrease in mean left ventricular end-diastolic diameter and left ventricular end-systolic diameter in the both groups. Mean left ventricular hypertrophy was decreased to 22.8 +/- 4.6 mm from 25.0 +/- 3.9 mm in the MH20A group, and 24.1 +/- 4.3 mm from 28.5 +/- 5.6 mm in the SJM21A group. These data suggest that aortic valve replacement with MH20A is useful for patients who have smaller body surface area (< 1.50 m2) with a small aortic annulus.

Aged↗