Bioprosthetic Mitral Stenosis Research Articles

Case report: Buddy wire technique to facilitate atrial septal crossing during transcatheter transseptal mitral valve implantation.

BackgroundTranscatheter mitral valve-in-valve implantation (MVIV) has emerged as a viable treatment option in patients at high risk for surgery. Occasionally, despite appropriate puncture location and adequate dilation, difficulty is encountered in advancing the transcatheter heart valve across interatrial septum.Case summaryWe describe a case of a 79-year-old woman with severe chronic obstructive pulmonary disease (COPD), prior surgical bioprosthetic aortic and mitral valve replacement implanted in 2007, atrial fibrillation, and Group II pulmonary hypertension who presented with progressively worsening heart failure symptoms secondary to severe bioprosthetic mitral valve stenosis and moderate-severe mitral regurgitation. Her symptoms had worsened over several months, with multiple admissions at other institutions with treatment for both COPD exacerbation and heart failure. Transoesophageal echocardiogram demonstrated preserved ejection fraction, normal functioning aortic valve, and dysfunctional mitral prosthesis with severe stenosis (mean gradient 13 mmHg) and moderate-severe regurgitation. After a multi-disciplinary heart team discussion, the patient underwent a transcatheter MVIV implantation. During the case, inability in advancing the transcatheter heart valve (THV) across interatrial septum despite adequate septal balloon pre-dilation was successfully managed with the support of a stiff ‘buddy wire’ anchored in the left upper pulmonary vein using the same septal puncture. The patient tolerated the procedure well and was discharged home.DiscussionOperators should be aware of potential strategies to advance the THV when difficulty is encountered in crossing the atrial septum despite adequate septal preparation. One such strategy is the use of stiff ‘buddy wire’ for support which avoids the need for more aggressive septal dilatation.

Doppler Parameters Derived from Transthoracic Echocardiography Accurately Detect Bioprosthetic Mitral Valve Dysfunction

Detecting bioprosthetic mitral valve dysfunction on transthoracic echocardiography can be challenging because of acoustic shadowing of regurgitant jets and a wide normal range of transvalvular gradients. Several studies in mechanical mitral valves have demonstrated the utility of the transthoracically derived parametersE (peak early mitral inflow velocity), pressure half-time, and the ratio of mitral inflow velocity-time integral(VTIMV) to left ventricular outflow tract velocity-time integral (VTILVOT) in detecting significant prostheticdysfunction. Uncertainty exists as to their applicability and appropriate cutoff levels in bioprosthetic valves. This study was designed to establish the accuracy and appropriate normal limits of routinely collected transthoracic Doppler parameters when used to assess bioprosthetic mitral valve function. A total of 135 clinically stable patients with bioprosthetic mitral valves who had undergone both transthoracic and transesophageal echocardiography within a 6-month period were retrospectively identified from the past 11years of the echocardiography database. Transthoracic findings were labeled as normal (n=81), regurgitant (n=44), or stenotic (n=10) according to the patient's transesophageal echocardiographic findings. Univariate and multivariate analyses were performed to identify Doppler parameters that detected dysfunction; then receiver operating characteristic curves were created to establish appropriate normal cutoff levels. The VTIMV/VTILVOT ratio was the most accurate Doppler parameter at detecting valvular dysfunction, with a ratio of >2.5 providing sensitivity of 100% and specificity of 95%. E>1.9m/sec was slightly less accurate (93% sensitivity, 72% specificity), while a pressure half-time of >170msec had both 100% specificity and sensitivity for detecting significant bioprosthetic mitral valve stenosis, (although it did not differentiate between regurgitant and normal). This study demonstrates that Doppler parameters derived from transthoracic echocardiography can accurately detect bioprosthetic mitral valve dysfunction. These parameters, particularly a VTIMV/VTILVOT ratio of >2.5, are a sensitive way of selecting patients to undergo more invasive examination with transesophageal echocardiography.

Severe Bioprosthetic Mitral Valve Stenosis and Heart Failure in a Young Woman with Systemic Lupus Erythematosus.

A 23-year-old African American woman with a past medical history of systemic lupus erythematous (SLE), secondary hypertension, and end stage renal disease (ESRD) on hemodialysis for eight years was stable until she developed symptomatic severe mitral regurgitation with preserved ejection fraction. She underwent a bioprosthetic mitral valve replacement (MVR) at outside hospital. However, within a year of her surgery, she presented to our hospital with NYHA class IV symptoms. She was treated for heart failure but in view of her persistent symptoms and low EF was considered for heart and kidney transplant. This was a challenge in view of her history of lupus. We presumed that her stenosis of bioprosthetic valve was secondary to lupus and renal disease. We hypothesized that her low ejection fraction was secondary to mitral stenosis and potentially reversible. We performed a dobutamine stress echocardiogram, which revealed an improved ejection fraction to more than 50% and confirmed preserved inotropic contractile reserve of her myocardium. Based on this finding, she underwent a metallic mitral valve and tricuspid valve replacement. Following surgery, her symptoms completely resolved. This case highlights the pathophysiology of lupus causing stenosis of prosthetic valves and low ejection cardiomyopathy.

Severe bioprosthetic mitral valve stenosis in pregnancy

A 21-year-old woman in the 16th week of pregnancy was admitted due to acute presentation of severe exertional dyspnea. She had undergone mitral valve replacement (MVR) with bioprosthetic valve for infective endocarditis 2 years ago. She developed congestive heart failure from mitral bioprosthetic valve stenosis due to early structural valve deterioration. She also had severe pulmonary hypertension and underwent a redo MVR using a mechanical valve prosthesis with good maternal outcome but fetal demise. This report brings up the debate about what type of valve should be used in women in reproductive age, and discusses the management of severe mitral stenosis and stenosis of a bioprosthetic valve during pregnancy. Surgical options can almost always be delayed until fetal maturity is achieved and a simultaneous cesarean section can be performed. However, under certain circumstances when the maternal welfare is in jeopardy the surgical intervention is mandatory even before the fetus reaches viability.

Percutaneous balloon valvuloplasty for bioprosthetic mitral valve stenosis

Percutaneous transcatheter mitral valvuloplasty is the indicated treatment of choice for symptomatic native mitral valve stenosis, but there have been limited reports of successful procedures of balloon valvuloplasty for bioprosthetic mitral valve stenosis. We present the case of a 62-year-old woman suffering from progressive dyspnea due to bioprosthetic mitral valve stenosis. The measured mean pressure gradient across the mitral valve was 30 mmHg and the mitral valve area was 0.73 cm(2). Redoing mitral replacement was considered high risk and was refused by the patient. Percutaneous balloon valvuloplasty was performed with an Inoue balloon catheter inflated to 20 mm. The patient's symptoms immediately improved after the procedure, with no procedure-related complications. The mean pressure gradient across the valve decreased to 19 mmHg, and the mitral valve area increased to 1.21 cm(2) in postprocedural echocardiography. We conducted a literature search and identified 26 cases of balloon valvuloplasty for degenerated bioprosthetic valves. Of these, 14 cases were bioprosthetic mitral valves, and the results were favorable. However, more case reports are required to establish an evidence base for future expert recommendation of balloon valvuloplasty of prosthetic mitral valve. Meanwhile, balloon valvuloplasty will serve a niche role in highly selected patients with prosthetic mitral valve stenosis.

Acute Bioprosthetic Mitral Valve Stenosis in a Patient with HITS

Acute thrombosis involving the left atrium and a bioprosthetic valve during the early postoperative period is an extremely rare complication of heparin-induced thrombocytopenia syndrome (HITS). We present a patient with early bioprosthetic mitral valve stenosis complicated by HITS in a patient with severe mitral regurgitation, atrial fibrillation, and severe left ventricular dysfunction.

Acute Reversible Bioprosthetic Mitral Valve Stenosis Caused by Heparin-Induced Thrombocytopenia

A 60-year-old woman with a 17-year-old prosthetic tilting disc mitral valve (MV) and chronic atrial fibrillation underwent emergency redo MV replacement for a stuck valve with a bioprosthetic valve (Medtronic Mosaic 27). Transesophageal echocardiography (TEE) on the fourth postoperative day showed a normal bioprosthetic valve. On the sixth postoperative day while the patient was still on intravenous heparin, her platelet count dropped to 63 000/μL and a heparin-induced thrombocytopenia (HIT) antibody assay was positive. Heparin was stopped, and the patient was treated with intravenous danaparoid sodium, a factor Xa inhibitor. Oral warfarin was started when thrombocytopenia resolved. The patient was in respiratory failure and could not be weaned off the ventilator. Contrast-enhanced computed tomography on the 14th postoperative day was negative for pulmonary emboli. However, large thrombi lining the left atrial wall and thickened bioprosthetic MV leaflets were seen (Figure 1). A repeat TEE the next day showed severe mitral stenosis, due to diffuse thrombosis and immobilization …

Percutaneous Transcatheter Balloon Valvuloplasty for Bioprosthetic Tricuspid Valve Stenosis

A 59-year-old woman was admitted to our hospital because of exertional dyspnea, abdominal distension, and leg edema over the past 2 weeks. She had a history of rheumatic fever at the age of 12 years. In 1983, at the age of 37, she had undergone tricuspid valve replacement with a Carpentier-Edwards bioprosthesis for tricuspid stenosis and mitral valve replacement with a mechanical valve for mitral stenosis. The physical examination on admission revealed marked edema in both legs. There was also presystolic pulsation of the liver, which was palpable 4 cm below the right costal margin. A Levine grade III/VI, rough, diastolic rumble at the lower left sternal border was accentuated during inspiration. Echocardiography revealed severe tricuspid stenosis and a large amount of ascites. The leaflets were thickened, …