Evaluation of prosthetic valve obstruction on electrocardiographically gated multidetector-row computed tomography--identification of subprosthetic pannus in the aortic position.

BACKGROUND: This study was performed to evaluate the diagnostic role of electrocardiographically gated multidetector-row computed tomography (MDCT) for prosthetic valve obstruction (PVO) in the aortic position. METHODS AND RESULTS: Between 2002 and 2006, 9 patients were diagnosed with PVO of an aortic bileaflet mechanical valve based on echocardiographic and cineradiographic criteria. These 9 patients were examined using MDCT before replacement of the mechanical valve, and intraoperative findings were compared to morphologic periprosthetic abnormalities observed on MDCT. CT attenuation (Hounsfield units; HU) of the periprosthetic abnormalities was measured to investigate the underlying cause of the PVO. MDCT showed subprosthetic masses extending beyond the prosthetic ring into the orifice of the valve. At reoperation, presence of subprosthetic pannus was confirmed in all of the 9 patients, but no periprosthetic thrombus was found. The mean CT attenuation of the subprosthetic pannus was 170 HU, and it was significantly greater than that obtained from the interventricular septum (108 HU; P<0.0001). CONCLUSIONS: MDCT can be used to clearly visualize subprosthetic pannus causing PVO and the mean CT attenuation of subprosthetic pannus is significantly higher than that of the interventricular septum on MDCT.

Disc wear and entrapment in a Starr-Edwards mitral caged-disc valve.

A case of wear and entrapment of a polyethylene disc observed in a Starr-Edwards (SE) mitral caged-disc valve at 37 years after implantation is reported. A 66-year-old woman who had undergone mitral valve replacement with a SE disc valve 37 years previously was admitted to the authors' hospital. Cinefluoroscopy showed the polyethylene disc of the SE valve to have impinged against a calcified mass on the left ventricular posterior wall, causing a tipping motion of the disc during opening. The valve was successfully replaced at surgery. A macroscopic examination of the excised valve revealed wear of the polyethylene disc at sites where the disc abutted the cage struts, and where it impinged on the calcified mass. The long-term durability of the SE caged-disc valves has been favorable; however, when implanted for over 20 years, they should be carefully followed up.

Twelve-year experience with the Carpentier-Edwards pericardial aortic valve at a single Japanese center.

Our aim was to evaluate the long-term results of implantation of the Carpentier-Edwards pericardial (CEP) valve in the aortic position. Between January 1996 and December 2007, 244 patients who underwent aortic valve replacement using the CEP valve were enrolled in this study. A 19-mm valve was used in 39 patients, a 21-mm valve in 94 patients, a 23-mm valve in 81 patients, and a 25-mm valve in 30 patients. The early and the late results were evaluated. Furthermore, echocardiographic examination was performed at follow-up. There were 5 early deaths, with an early mortality rate of 2.0%. Follow-up was performed in 95.4% of the survivors of the operation for a mean period of 4.1 years. Actuarial survival rates at 5, 10, and 12 years were 85.3 ± 2.8, 80.0 ± 3.7 and 70.0 ± 9.8%, respectively. Thromboembolism was observed in 6 patients, endocarditis in 2 patients, reoperation in 4 patients, and structural valve deterioration in 2 patients. Actuarial freedoms from thromboembolism, endocarditis, and reoperation at 10 years were 96.9 ± 0.14, 97.7 ± 0.16, and 97.0 ± 0.16%, respectively. Echocardiographic examination revealed that the pressure gradients across the valve prosthesis for valves of each size were acceptable. Left ventricular mass index decreased significantly in all valve sizes. The long-term results of implantation of the CEP bioprosthesis in the aortic position were satisfactory. The CEP bioprosthesis maintained its hemodynamic performance even as late as 10 years after implantation.

Concurrent submitral left ventricular aneurysm and an aneurysm of the sinus of valsalva: report of a case.

We herein describe a rare case of a concurrent submitral left ventricular (LV) aneurysm and an aneurysm of the sinus of Valsalva in a 65-year-old Japanese woman. The patient had a history of mitral valve replacement (MVR) for mitral regurgitation caused by a submitral LV aneurysm at the age of 58. At the time of the MVR, the orifice of the submitral LV aneurysm without thrombi was beneath the posterior leaflet, but surgical repair of the submitral LV aneurysm was not attempted. Although the patient was asymptomatic, when she underwent an echocardiogram at 65 years of age an aneurysm of the noncoronary sinus of Valsalva was detected. However, echocardiography performed before the initial operation had shown that the aneurysm of the sinus of Valsalva was coexistent with the submitral LV aneurysm. Since the submitral LV aneurysm revealed no progressive enlargement during the 7 years, patch closure of the aneurysm of the sinus of Valsalva alone was successfully performed.

[Long-term outcomes of thoracic endovascular aortic repair with homemade stent-grafts].

We reviewed our experience with homemade stent-grafts in the repair of thoracic aortic lesions. The objective of this study was to assess the long-term outcomes of this therapy. From 1999 to 2008, homemade stent-grafts were inserted in 94 patients with various thoracic diseases. The endoprostheses were stainless steel Z-stents covered with polyester graft and were custom designed for each patient. Placement of the stent-grafts was technically successful in 85 of the 94 patients (90%). Within 30 days after the treatment, 4 patients died, 3 had cerebral infarction, and 3 had the onset of paraplegia or paraparesis. Primary endoleaks were observed in 10 patients (11%). During the mean follow-up period of 43 +/- 29 months, 10 patients had endoleaks and 8 had stent-graft migration. The aneurysm-related mortality rate was 12%. Our early outcomes of elective and emergency thoracic endovascular aortic repair with homemade stent-grafts demonstrated their therapeutic effectiveness in high-risk patients with various thoracic diseases. Endoleaks and migration were, however, the factors most responsible for secondary intervention in the mid-term period. Careful follow-up of the treated patients is needed to avoid the major complication in the long-term period.

Mitral stenosis due to pannus overgrowth after rigid ring annuloplasty.

Although mitral stenosis (MS) due to pannus overgrowth after mitral valve repair for rheumatic mitral regurgitation (MR) is not uncommon, it is extremely rare in relation to non-rheumatic mitral regurgitation. Whilst it has been suggested that the rigid annuloplasty ring induces pannus overgrowth in the same manner as the flexible ring, to date only in cases using the flexible ring has pannus formation been confirmed by a pathological examination after redo surgery. The case is described of a woman who had undergone mitral valve repair using a 28 mm rigid ring three years previously because of non-rheumatic MR, and subsequently suffered from MS due to pannus formation over the annuloplasty ring. To the present authors' knowledge, this is the first report of MS due to pannus formation after mitral valve repair using a rigid annuloplasty ring to treat non-rheumatic MR documented at reoperation.

Heart valve surgery in octogenarians: operative and long-term results.

This study was performed to evaluate surgical outcomes in octogenarian patients undergoing valve surgery. Sixty patients (mean age 82.3 ± 1.9 years) who underwent valve surgery were reviewed. Aortic valve disease was found in 65% of the patients. Preoperatively, 20% of the patients were in NYHA class IV. An urgent operation and concomitant coronary artery bypass grafting were performed in ten patients each. A bioprosthetic valve was exclusively used for valve replacement except in two patients. Mitral valve repair was done in seven patients. Operative mortality was 13.3% for the period. No risk factors for operative mortality were detected by multivariate analysis; however, urgent operation, preoperative NYHA class IV, preoperative renal dysfunction, perioperative use of an intra-aortic balloon pumping, and prolonged cardiopulmonary bypass time had significant effects on operative mortality. The actuarial survival rate at 1 and 3 years after surgery was 82.6 and 71.5%, respectively, and 97.6% of late survivors reported that their activity level was equal to or better than the preoperative level. Valve surgery can be performed in octogenarian patients with acceptable mortality, good long-term results, and good quality of life. Early referral to surgery should be important to obtain a better postoperative outcome.

Treatment for mechanical valve thrombosis in the right heart: combined pharmacological and mechanical thrombolysis.

We report clinical results of combined pharmacological and mechanical thrombolysis for mechanical prosthetic valve thrombosis (PVT) in the right heart. Between January 1992 and December 2008, combined thrombolysis, which consisted of an intravenous infusion of urokinase together with mechanical disruption of thrombus in a prosthetic valve by temporarily increasing the cardiac pacing rate, was performed in three patients with four cases of mechanical PVT in the right heart. The prosthetic valve in all three patients was a bileaflet mechanical valve, and was located in the tricuspid position in two patients and in the pulmonary position in the remaining patient. PVT was diagnosed by echocardiography and cineradiography. Thrombolysis was successful in all four cases in the three patients, and no hemorrhagic complications or clinically symptomatic pulmonary embolisms were observed. Mechanical disruption of thrombus using a pacemaker appears to be an effective adjunctive modality to thrombolysis with fibrinolytic agents for PVT in the right heart. Combined pharmacological and mechanical thrombolysis may improve success rates and reduce the time required for thrombolysis of PVT.

Obstruction of St. Jude medical valves in the aortic position: plasma transforming growth factor type beta 1 in patients with pannus overgrowth.

The study investigated the hypothesis that plasma transforming growth factor type beta 1 (TGF-beta1) initiated pannus overgrowth in cases with aortic prosthetic valve dysfunction (PVD). Patients with obstruction of an aortic St. Jude Medical valve in 26 cases (PVD group) and without obstruction in 48 cases (control group) were studied. Plasma TGF-beta1, the intensity of the prothrombin time-international normalized ratio (PT-INR), and the interruption of an oral anticoagulant medicine were conducted. Plasma TGF-beta1 levels in the PVD group (87.7 +/- 29.2 ng/mL) were significantly higher (P < 0.05) than in the control group (73.7 +/- 25.2 ng/mL). The interruption of an oral anticoagulant medicine in 54% of the PVD group versus 12% of the control group was identified (P < 0.001). The mean value of the PT-INR in the PVD group (1.75 +/- 0.30) and control group (1.75 +/- 0.30) was not significantly different (P = 0.82). In conclusion, elevated levels of plasma TGF-beta1 may play a role in pannus overgrowth.

Pannus overgrowth after mitral valve replacement with a Carpentier-Edwards pericardial bioprosthesis.

A Carpentier-Edwards pericardial (CEP) bioprosthesis was explanted from an 81-year-old woman due to nonstructural dysfunction 9 years after mitral valve replacement. The nonstructural dysfunction produced severe regurgitation in the mitral position. During the surgery, excessive pannus overgrowth was seen on the left ventricular side of the CEP bioprosthesis. Pannus overgrowth was prominent on one leaflet. That leaflet was stiff and shortened due to the excessive overgrowth of pannus. In this patient, the distortion of one leaflet was the main reason for transvalvular leakage of the CEP bioprosthesis in the mitral position. A new CEP bioprosthesis was implanted in the mitral position. Pathological analysis revealed fibrotic pannus with a small amount of cellular material over the leaflets of the resected CEP valve. This change was marked on the distorted leaflet.

[Long-term results of aortic root replacement with a composite graft].

We analyzed the long-term results of aortic root replacement with a composite graft. Since 1992, 127 patients had undergone aortic root replacement with a composite graft. There were 92 men and 35 women with a mean age of 56.5 years. There were 69 patients with annuloaortic ectasia, 17 aortic dissections, and 41 ascending aortic dilatation due to aortic valve disease. Marfan syndrome was diagnosed in 19 patients. As surgical procedure, button technique was used in 90 patients, Cabrol technique in 11, and Piehler technique in 26. Open distal anastomosis was performed in 82 patients to avoid clamp injury of rest aorta. Early mortality was 3.1% and no major morbid events had occurred. Follow-up was completed in 95.9% of the patients and the mean follow-up period was 6.1 years. Actuarial survival at 5, 10, and 15 years was 86.2%, 83.4%, and 83.4%, respectively. Actuarial freedom from aortic valve reoperation at 10 and 15 years was 99.2% and 95.7%, respectively. The results of aortic root replacement with a composite graft were excellent. This procedure should be the 1st choice for surgical treatment of the aortic root disease.

Edge-to-edge repair for mitral regurgitation: a clinical and exercise echocardiographic study.

BACKGROUND AND AIM OF THE STUDY: The durability and potential for creating functional mitral stenoses are major concerns in the edge-to-edge (E-to-E) repair of mitral regurgitation (MR). METHODS: Valve repair for MR was performed using the classical Carpentier technique in 120 patients (group C), and with the E-to-E technique in 37 patients (group E). A ring annuloplasty was performed in all patients. The mid-term results were examined and exercise echocardiography was conducted. RESULTS: No significant differences were observed between the two groups with regards to early and late mortality rates, actuarial survival rate and valve-related complication-free rate at five years after surgery. Postoperatively, MR was decreased significantly in both groups. Exercise echocardiography was undertaken in 35 operative survivors (20 from group C, 15 from group E). At peak exercise, the mean transmitral pressure gradient (MTPG) increased significantly in both groups. Systolic pulmonary artery pressure (SPAP) was also significantly elevated, but still within the accepted upper limits in both groups. The mitral valve area (MVA) showed no significant increase in either group. At peak exercise there were no significant differences in MTPG, SPAP and MVA between the two groups. CONCLUSION: Edge-to-edge repair is equally effective and durable as a conventional repair using the Carpentier technique. A mitral valve redesigned by E-to-E repair with ring annuloplasty may be slightly restrictive compared to a normal healthy mitral valve under exercise conditions; however, the hemodynamic performance did not differ significantly from that of a valve repaired with the Carpentier technique. These hemodynamics were not related to the use of E-to-E repair per se as the only causal factor, but rather to the ring annuloplasty.

Mid-term results of valve replacement with the ATS valve: a seven-year follow up.

BACKGROUND AND AIM OF THE STUDY: The ATS open pivot bileaflet valve has been the prosthesis of choice at the authors' hospital since 1997. Herein is presented a retrospective analysis of the mid-term results of valve replacement with the ATS valve prosthesis. METHODS: Between 1997 and 2005, a total of 280 patients (mean age 58.3 years) underwent valve replacement with the ATS valve; these included 133 aortic valve replacements (AVR), 115 mitral valve replacements (MVR), and 32 double (aortic plus mitral) valve replacements (DVR). Preoperatively, 162 patients (57.9%) were in NYHA functional class II, 97 (34.6%) in class III, 19 (6.8%) in class IV, and two (0.7%) in class V. Atrial fibrillation was detected in 105 patients (37.5%), and significant coronary artery disease was found concomitantly in 13 (4.6%). Postoperative anticoagulant therapy consisting of warfarin and an antiplatelet drug was usually instituted on the first postoperative day, and the International Normalized Ratio maintained between 1.6 and 2.5. RESULTS: Overall hospital mortality was 3.6% (n = 10). Hospital survivors were followed for a mean period of 4.2 years (maximum 10 years); the total follow up was 1,127.9 patient-years (pt-yr). Follow up was complete for 267 patients (98.9%). Actuarial survival at seven years was 87.1% for AVR, 79.8% for MVR, and 90.1% for DVR. The probability of freedom from valve-related death at seven years was 96.7% for AVR, 94.4% for MVR, and 100% for DVR. The linearized rates for postoperative complications were thromboembolism 1.2%/pt-yr, major bleeding 0.7%/pt-yr, prosthetic valve endocarditis 0.2%/pt-yr, non-structural dysfunction 0.7%/pt-yr, and reoperation 0.5%/pt-yr. Structural valve failure was not encountered. CONCLUSION: This clinical experience with the ATS open pivot heart valve demonstrated low rates of adverse events and valve-related complications.

Subdural hematoma after open-heart surgery.

Four cases are described of acute subdural hematoma that occurred after valve replacement in patients receiving anticoagulant therapy. All four patients experienced rapid deterioration of consciousness or neurological dysfunction, to varying degrees, between two and 42 days after valve replacement; emergency brain computed tomography scanning demonstrated the presence of subdural hematoma. The neurological problems were completely resolved by removal and drainage of the hematoma in three patients, while conservative management was performed with no aggravation of neurological symptoms in the fourth patient.

Embolic myocardial infarction and left ventricular rupture due to mitral valve endocarditis.

A left ventricular rupture due to embolic myocardial infarction is extremely rare. A 72-year-old woman developed an acute embolic myocardial infarction and mitral regurgitation due to infective endocarditis. Two days after the infarction, a left ventricular free wall rupture occurred after transesophageal echo examination. She received an epicardial patch and mitral valve replacement. Perioperatively, an intra-aortic balloon pump and long-term antibiotics were used. The postoperative course was uneventful, and she is doing well 10 months after surgery.

Obstruction of St Jude Medical valves in the aortic position: histology and immunohistochemistry of pannus.

OBJECTIVE: This study aims to reveal the morphological, histological, and immunohistochemical mechanism of pannus formation using resected pannus tissue from patients with prosthetic valve dysfunction. METHOD: Eleven patients with prosthetic valve (St Jude Medical valve) dysfunction in the aortic position who underwent reoperation were studied. We used specimens of resected pannus for histological staining (hematoxylin and eosin, Grocott's, azan, elastica van Gieson) and immunohistochemical staining (transforming growth factor-beta, transforming growth factor-beta receptor 1, alpha-smooth muscle actin, desmin, epithelial membrane antigen, CD34, factor VIII, CD68KP1, matrix metalloproteinase-1, matrix metalloproteinase-3, and matrix metalloproteinase-9). RESULTS: Pannus without thrombus was observed at the periannulus of the left ventricular septal side; it extended into the pivot guard, interfering with the movement of the straight edge of the leaflet. The histological staining demonstrated that the specimens were mainly constituted with collagen and elastic fibrous tissue accompanied by endothelial cells, chronic inflammatory cells infiltration, and myofibroblasts. The immunohistochemical findings showed significant expression of transforming growth factor-beta, transforming growth factor-beta receptor 1, CD34, and factor VIII in the endothelial cells of the lumen layer; strong transforming growth factor-beta receptor 1, alpha-smooth muscle actin, desmin, and epithelial membrane antigen in the myofibroblasts of the media layer; and transforming growth factor-beta, transforming growth factor-beta receptor 1, and CD68KP1 in macrophages of the stump lesion. CONCLUSIONS: Pannus appeared to originate in the neointima in the periannulus of the left ventricular septum. The structure of the pannus consisted of myofibroblasts and an extracellular matrix such as collagen fiber. The pannus formation after prosthetic valve replacement may be associated with a process of periannular tissue healing via the expression of transforming growth factor-beta.

Usefulness of a multidetector-row computed tomography scanner for detecting pannus formation.

BACKGROUND: Prosthetic valve dysfunction (PVD) as a result of pannus or thrombus formation is an infrequent but serious complication. Currently available diagnostic tools, however, are insufficient to detect a minute pannus and thrombi. The use of a more advanced diagnostic image, multidetector-row computed tomography scanner, may enable us to determine the anatomic and functional causes of PVD. METHODS: Patients who underwent aortic valve replacement with a St. Jude Medical valve were examined by transthoracic echocardiography and cineradiography to diagnose PVD. Sixteen patients with PVD (PVD group) and 12 patients with normal prosthetic valve function (control group) were studied using the multidetector-row computed tomography scanner. The multidetector-row computed tomography findings in 2 patients with PVD were validated by the observations during reoperation. RESULTS: In 13 of 16 patients (81%) in the PVD group and 3 of 12 patients (25%) in the control group, multidetector-row computed tomography demonstrated that an abnormal small tissue, regarded as pannus, was found to extend from the left ventricular septum into the pivot guard. These findings were confirmed by the observations during reoperation in 2 patients in the PVD group. CONCLUSIONS: Multidetector-row computed tomography can be a useful diagnostic technique for anatomic and functional evaluation of PVD as a result of pannus formation.

High-intensity transient signals due to prosthetic valve obstruction: diagnostic and therapeutic implications.

BACKGROUND: High-intensity transient signals (HITS) can be detected by transcranial Doppler ultrasonography (TCD) in patients carrying a mechanical prosthetic valve. The HITS counts and a frequency analysis were evaluated in patients with prosthetic valve obstruction in the aortic position. METHODS: Simultaneous echocardiographic, cineradiographic, and TCD evaluations for a St. Jude Medical valve were performed in 108 patients. All patients were asymptomatic and had no significant stenosis of the carotid artery. The HITS were identified according to criteria established by consensus of the International Cerebral Hemodynamics Symposium. RESULTS: The HITS counts in 69 patients with normal prosthetic valve function were 2.2 +/- 4.4, and the counts in 39 patients with prosthetic valve obstruction (group D) were 8.3 +/- 10.8. This difference was significant (p = 0.0002). In 2 patients of group D who had a greater rate of less than 400 Hz HITS, which were produced by solid microemboli, thrombolysis resulted in a mitigation of restricted leaflet movement equal to or greater than 10(o). The total number of HITS decreased and the rate of less than 400 Hz HITS also markedly decreased after thrombolysis in these 2 patients. On the other hand, 4 patients who obtained no improvement of leaflet movement by thrombolysis had lower rates of less than 400 Hz HITS than did the 2 patients. CONCLUSIONS: These results suggest that measurement of HITS counts is useful for detection of prosthetic valve obstruction, and that a frequency analysis of HITS may be valuable to clarify the cause of the obstructed prosthetic valves.

Left ventricular outflow tract pseudoaneurysm after aortic valve replacement: case report.

A 68-year-old woman was admitted for angina pectoris and general fatigue without symptoms or signs of infective endocarditis. The patient had undergone re-replacement of an aortic prosthetic valve three months previously. Transesophageal echocardiography revealed an echo-free cavity in the mitral-aortic intervalvular fibrosa region just below the aortic annulus, communication of the echo-free cavity with the left ventricular outflow tract, and turbulent flow into the cavity. Left ventriculography revealed a cavity that arose just below the aortic prosthetic valve, and which expanded in systole and collapsed in diastole. Coronary angiography showed significant stenosis of the proximal right coronary artery, but neither stenoses nor compression were found in the left coronary artery. Patch closure of the pseudoaneurysm and aortic root replacement using a Freestyle valve with reconstruction of the coronary arteries were successfully performed. Surgical trauma to the intervalvular fibrosa during removal of the original prosthetic valve may have caused pseudoaneurysm formation in this patient.

Left atrial thrombosis following mitral valve repair and maze procedure: case report.

The case is described of a 71-year-old woman with left atrial thrombosis after successful mitral valve repair and a Kosakai-maze procedure. At three months after surgery, electrocardiography showed a normal sinus rhythm, but echocardiography revealed a mural thrombus on the posterior wall of the left atrium. During those three months, the anticoagulation level (thrombotest index range: 29-41%) was lower than target level. Anticoagulant therapy with heparin plus warfarin failed to reduce the thrombus size. Anticardiolipin antibodies were positive, and lupus anticoagulants negative. A Doppler study of the mitral valve indicated peak velocity 1.48 m/s, mean pressure gradient 4.5 mmHg, and valve area 2.1 cm2. During reoperation, an old spherical thrombus (weight 38 g) which was firmly adhered to the posterior wall and included an incision line of the Kosakai-maze procedure, was identified and totally removed. After reoperation, the patient received warfarin and an antiplatelet agent to maintain the INR at 2.5-3.5. Echocardiography performed at 11 months postoperatively revealed no thrombus formation on the left atrium.