Prosthetic Valve Ring Research Articles

Repeat aortic valve replacement (AVR) for pseudoaneurysm of mitral-aortic intervalvular fibrosa (P-MAIVF) repair due to hemolytic anemia 6 years after AVR: a case report

BackgroundPseudoaneurysm of the mitral-aortic intervalvular fibrosa (P-MAIVF) after infective endocarditis and/or valve replacement is rarely reported, and transesophageal echocardiography and cardiac multidetector computed tomography are useful for diagnosis. Surgery is mostly recommended to prevent fatal complications.Case presentationA 61-year-old man underwent repeat aortic valve replacement (AVR) with repair of a P-MAIVF due to hemolytic anemia 6 years after AVR, and 4 months after treatment of sepsis and an infected abdominal aortic aneurysm. Two years after the surgery, the patient is alive and well with no recurrence.ConclusionsThe present case was considered to be a very rare case in which surgery was performed because the blood flow entering and leaving the P-MAIVF contacted the prosthetic valve ring, resulting in hemolysis, severe anemia, and heart failure.

CASSIA (cardiology software suite for image analysis): a potential new tool for the evaluation of [18F]FDG PET/CT in the setting of infective endocarditis

PurposeDue to the high morbidity and mortality of infective endocarditis (IE), medical imaging techniques are combined to ensure a correct diagnosis. [18F]FDG PET/CT has demonstrated the ability to improve diagnostic accuracy compared with the conventional modified Duke criteria in patients with suspected IE, especially those with prosthetic valve infective endocarditis (PVIE). The aim of this study is to provide an adjunctive diagnostic tool to improve the diagnostic accuracy in cardiovascular infections, specifically PVIE.MethodsA segmentation tool to extract quantitative measures of [18F]FDG PET/CT image studies of prosthetic heart valve regions was developed and validated in 20 cases of suspected PVIE, of which 9 were confirmed. For that, Valvular Heterogeneity Index (VHI) and Ring-to-Center Ratio (RCR) were defined.ResultsResults show an overall increase in the metabolic uptake of the prosthetic valve ring in the studies with confirmed PVIE diagnosis (SUVmax from 1.70 to 3.20; SUVmean from 0.86 to 1.50). The VHI and RCR showed areas under the curve of 0.727 and 0.808 in the receiver operating characteristics curve analyses, respectively, for PVIE diagnosis. Mann–Whitney U tests showed statistically significant differences between groups for RCR (p = 0.02). Visual analyses and clinical reports were concordant with the extracted quantitative metrics.ConclusionThe proposed new method and presented software solution (CASSIA) provide the capability to assess quantitatively myocardial metabolism along the prosthetic valve region in routine [18F]FDG PET/CT scans for evaluating heart valve infectious processes. VHI and RCR are proposed as new potential adjunctive measures for PVIE diagnosis.

Melody valve implantation in the pulmonary and tricuspid position

Percutaneous implantation of valved stents is now routinely performed to treat pulmonary valve regurgitation and stenosis. In addition, there are isolated reports of implantation of valved stents in the tricuspid position to treat prosthetic tricuspid stenosis or regurgitation when a prosthetic valve ring exists. We present a case in which a patient with combined severe tricuspid valve and pulmonary valve disease was successfully treated with sequential implantation of percutaneous valved stents in a single procedure. The procedure was straightforward, of short duration, and dramatically improved the patient's functional status.

A case of prosthetic valve endocarditis caused by Streptococcus constellatus as a rare agent of endocarditis

We present a case of prosthetic valve endocarditis, which was caused by a rare etiological agent, Streptococcus constellatus. In our case, transesophageal echocardiography showed a large and broad abscess formation throughout the patient's aortic prosthetic valve ring and left atrium. Despite specific intravenous antibiotic therapy, the infection was uncontrollable, and the patient underwent surgical treatment. The pathogen rarely causes endocarditis, but it is known to have a strong potential to form abscess, and therefore its infection may be more serious than other Streptococcus species. Our case seems to be the first report of surgical treatment of PVE caused by S. constellatus. As in our case, transesophageal echocardiography is useful for the detection of vegetation and abscess, and early cardiac surgery may be a more appropriate therapeutic approach for endocarditis caused by S. constellatus.

Mitral Valve Dynamics in Severe Aortic Stenosis before and after Aortic Valve Replacement

The aortic and mitral valves are anatomically linked through a fibrous continuity. The investigators hypothesized that severe aortic stenosis (AS) would alter this fibrous continuity, affecting both the mitral valve and left ventricular function, and that mitral valve function would be altered after aortic valve replacement (AVR). The aim of this study was to evaluate the impact of AS and its treatment with surgical AVR on the mitral valve. Three-dimensional transesophageal echocardiography (using a Philips iE33 system) was performed on 49 patients: 20 controls with normal valves and left ventricular function, 20 with AS and normal left ventricular function studied before and after AVR, and nine with systolic heart failure and normal valves. Custom software tracked the aortic and mitral valves in three-dimensional space, allowing automated measurements of aortic and mitral annular (MA) morphology throughout the cardiac cycle. Patients with AS before AVR had reduced MA velocities. After AVR, aortic and MA areas were significantly smaller throughout the cardiac cycle compared with controls and pre-AVR values. MA displacement was reduced after AVR and in patients with systolic heart failure compared with those with AS and controls. Dynamic MA function is changed with AS and after AVR through alterations in the aortic-mitral fibrous continuity. The prosthetic valve ring results in reduced aortic and MA areas, which could affect blood flow in and out of the left ventricle. These changes suggest that the design of future prosthetic aortic valves should be more flexible to preserve the function of the aortic-mitral fibrous continuity.

Misleading image of mechanical valve leaflet by transesophageal echocardiography.

Although bileaflet prosthetic valve function is commonly assessed by means of transesophageal echocardiography (TEE) during surgery, the author reports that the leaflet image is not a real image but an artifact. As the depth of the transducer is altered, the leaflet image is gradually skewed in relation to the plane of the prosthetic valve ring. The leaflet-like image consistently overlaps the line that is drawn from the transducer position to the atrial side edge of the leaflet, indicating that this image is caused by reverberations. Three-dimensional TEE shows that the leaflet image is not semilunar but is elongated towards the left ventricle and unusually tilted. As viewed from the ventricular side, the ring image is elongated and forms a cylinder-like image in the left ventricle, and the leaflets appear to be opening and closing at the bottom of this cylinder. Therefore, TEE assessment of leaflets in the open position can be misleading.

The disk of bileaflet mechanical mitral valve prosthesis jammed by ruptured papillary muscle

The disk of bileaflet mechanical mitral valve prosthesis jammed by ruptured papillary muscle

Modified button-Bentall operation for aortic root replacement: the miniskirt technique

Background. The aim of this study was to evaluate the midterm results of a modified button-Bentall operation (modified-bB) specifically designed to incorporate any type of prosthetic valve in composite conduit aortic root replacement. Methods. Between 1991 and 2000, a total of 135 patients underwent modified-bB for annuloaortic ectasia (74 patients), type A dissection (31), or aortic aneurysm without dissection (30). Of these, 34 were emergencies (25.2%). A total of 50 bioprostheses (study group 1) and 85 bileaflet mechanical prostheses (study group 2) were implanted. Group 1 mean age was 66.9 ± 7.4 years versus 51.5 ± 12.1 years in group 2 ( p < 0.001). Composite-conduit creation occurred during proximal suture line construction as a single-step maneuver. Interrupted extracardiac polyester mattress sutures sequentially entered the aortic annulus, the prosthetic valve ring, and the vascular graft 7 mm from its free edge (miniskirt). Running monofilament suture line secured proximal hemostasis, buttressing aortic remnants and graft edge. Coronary reimplantation was accomplished in all cases by the button technique. Concomitant procedures were performed in 51 patients (37.8%). Results. The 30-day mortality was 5.18% (7/135 patients). Eight patients (5.9%) required revision for proximal (1 patient), coronary button (3), or distal (4) anastomosis leakage. Three patients (2.2%) perioperatively developed nonfatal inferior myocardial infarction. Kaplan-Meier 9-year survival is 91.8% ± 0.026 SE with 88.1% (95% confidence limits 71.7% to 95.5%) reoperation freedom. According to the Cox proportional hazard method, stratification of the risk for death according to prosthesis type indicates previous operation ( p = 0.001) and emergency ( p = 0.0465) as independent predictors of hospital mortality. Associated procedures to modified-bB increased risk of reoperation ( p = 0.031). Conclusions. Modified-bB was associated with low mortality, excellent midterm survival, and freedom from reoperation. Absence of valve-to-graft tapering, reduced coronary button anastomosis tension, and prosthesis selection according to patient profile, are apparent advantages of modified-bB.

Compression of anomalous circumflex coronary artery by a prosthetic valve ring

Anomalous origin of the circumflex coronary artery from the right aortic sinus, with a retroaortic course, is usually without consequence. We report a patient who underwent aortic valve replacement for bicuspid aortic valve. The prosthesis sewing ring distorted the circumflex, producing myocardial infarcts and sudden death during exercise.

Surgical repair of aortic root aneurysms in 280 patients

Bentall's technique for repair of annuloaortic ectasia has been associated with postoperative bleeding and with false aneurysms at the anastomotic site between the coronary orifices and valve-containing graft. To reduce the incidence of these complications, we modified the Bentall procedure, using a simplified technique to implant the graft and to create a fistula between the closed perigraft space and right atrium to control bleeding. A continuous suture of monofilament polypropylene was used to implant the prosthetic valve ring and to anastomose the coronary orifices to the Dacron fabric. In some instances, a brief period of hypothermic circulatory arrest was needed to perform the distal aortic anastomosis. Among 562 patients undergoing operation for aneurysm of the ascending aorta between January 1, 1980, and February 28,1990, 280 underwent graft replacement with a valve-containing composite conduit. Most (82%) had annuloaortic ectasia. In 267, we performed a classic Bentall procedure with direct anastomosis between the coronary orifices and fabric graft. The remaining 13 patients underwent other procedures for coronary connection. Early mortality was 5.0%. Reoperation for bleeding was needed in 13.2% of patients who underwent operation before we used the right atrial fistula technique and in 4.4% after we began to use the technique ( p = 0.044). Actuarial survival was 71% at 5 years and 65% at 7 years. For hospital survivors, it was 76% at 5 years and 70% at 7 years. During follow-up, only 9 patients have required reoperation. A false aneurysm at the coronary anastomosis, which was associated with prosthetic valve endocarditis, developed in 1 patient. No permanent fistulas have developed. Thus, by using simplified methods to implant the graft and to control postoperative bleeding, the Bentall technique can be performed successfully with excellent early and late results.

Surgical consideration of replacement of the ascending aorta and aortic valve with a composite valve graft--operative and long-term results of Bentall and DeBono procedure.

Our experience with the Bentall and DeBono procedure is reviewed. Between April, 1977 and April, 1985, seventeen patients underwent repair of annulo-aortic ectasia (9 cases), and dissecting aneurysm with aortic regurgitation (8 cases). Three patients had cardiac tamponade due to rupture of dissecting aneurysm. In regard to this procedure, we recently performed the continuous suture method on the prosthetic valve ring, coronary ostia, and distal anastomosis sites. In this study, there was one early death due to a sudden rupture of the dissecting aneurysm of the left thoracic cavity on the 10th postoperative day. In addition, there were two late deaths due to sepsis and suspected arrhythmia. The late follow-up period ranged from 6 months to 8 years (mean 35 months), and all patients were in NYHA Class I or II. We conclude that the composite valve graft method is an excellent technique for annuloaortic ectasia and ascending aortic dissections with aortic regurgitation because of its low operative mortality and fair survival rate.

Nocardia Asteroides aortitis with perforation of the aorta

A 53-year-old man died of nocardial aortitis eight months after undergoing aortic valve replacement. Autopsy revealed vegetation in the area of a previous aortotomy incision and a small perforation of the aorta enclosed by pericardium immediately above the prosthetic valve ring. Prosthetic valve endocarditis was not present. Multiple splenic infarcts, microabscesses of both kidneys, and myocarditis were identified. Antemortem blood cultures and postmortem cultures of the aortic vegetation grew Nocardia asteroides.