1.Measurement of Opening and Closing Angles of Aortic Valve Prostheses In Vivo Using Dual-Source Computed Tomography: Comparison with Those of Manufacturers' in 10 Different Types.
Young Joo SUH ; Young Jin KIM ; Yoo Jin HONG ; Hye Jeong LEE ; Jin HUR ; Dong Jin IM ; Yun Jung KIM ; Byoung Wook CHOI
Korean Journal of Radiology 2015;16(5):1012-1023
OBJECTIVE: The aims of this study were to compare opening and closing angles of normally functioning mechanical aortic valves measured on dual-source computed tomography (CT) with the manufacturers' values and to compare CT-measured opening angles according to valve function. MATERIALS AND METHODS: A total of 140 patients with 10 different types of mechanical aortic valves, who underwent dual-source cardiac CT, were included. Opening and closing angles were measured on CT images. Agreement between angles in normally functioning valves and the manufacturer values was assessed using the interclass coefficient and the Bland-Altman method. CT-measured opening angles were compared between normal functioning valves and suspected dysfunctioning valves. RESULTS: The CT-measured opening angles of normally functioning valves and manufacturers' values showed excellent agreement for seven valve types (intraclass coefficient [ICC], 0.977; 95% confidence interval [CI], 0.962-0.987). The mean differences in opening angles between the CT measurements and the manufacturers' values were 1.2degrees in seven types of valves, 11.0degrees in On-X valves, and 15.5degrees in ATS valves. The manufacturers' closing angles and those measured by CT showed excellent agreement for all valve types (ICC, 0.953; 95% CI, 0.920-0.972). Among valves with suspected dysfunction, those with limitation of motion (LOM) and an increased pressure gradient (PG) had smaller opening angles than those with LOM only (p < 0.05). CONCLUSION: Dual-source cardiac CT accurately measures opening and closing angles in most types of mechanical aortic valves, compared with the manufacturers' values. Opening angles on CT differ according to the type of valve dysfunction and a decreased opening angle may suggest an elevated PG.
Adult
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Aortic Valve/*radiography
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Female
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Heart Valve Diseases/therapy
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*Heart Valve Prosthesis
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Heart Valve Prosthesis Implantation/*instrumentation
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Humans
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Male
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Middle Aged
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Retrospective Studies
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Tomography, X-Ray Computed/methods
2.Preliminary study of a new heart valve prostheses implanted with minimally invasive techniques: pulsatile-flow testing in vitro.
Jinglong TANG ; Shuo WANG ; Li LIU ; Jian WANG ; Chunren WANG
Journal of Biomedical Engineering 2013;30(1):166-169
The aim of this study was to investigate the pulsatile-flow performance in vitro of a new heart valve prostheses implanted with minimally invasive techniques (HVPMIT). Three HVPMITs were tested valves and another three original biological heart valve prostheses acted as reference valves. The pulsatile-flow parameters (including mean pressure drop, regurgitant percentage of stroke volume, and effective orifice area) were tested in a pulse duplicator according to the methods listed in ISO5840-2005 and GB 12279-2008. The results demonstrated that the regurgitant percentage of stroke volume of tested valves was up to 13%. It was significantly higher than that of the reference valves. This result suggested that paravalvular leakage had occurred in the tested valves. It was found in the further analysis that because HVPMIT was not sewn into the heart tissue when the HVPMIT was implanted in vivo and there was not a sewing ring in the HVPMIT, when tested valves were fixed in the pulse duplicator, some gaps might exist between the stent of HVPMIT and the fix gasket, and the paravalvular leakage could therefore take place through these gaps. This study demonstrated that there are significant differences in the shape, structure, fixation in vivo and clinical operational methods between HVPMIT and original biological heart valve prostheses. It is necessary to establish new test methods which adapt for HVPMIT to evaluate its pulsatile-flow performance according to its own features.
Animals
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Cardiac Catheterization
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Heart Valve Prosthesis
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Heart Valve Prosthesis Implantation
;
adverse effects
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instrumentation
;
methods
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Minimally Invasive Surgical Procedures
;
methods
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Prosthesis Design
;
Pulsatile Flow
3.Percutaneous aortic valve replacement using a W-model valved stent: a preliminary feasibility study in sheep.
Yuan BAI ; Gang-Jun ZONG ; Yan-Yan WANG ; Hai-Bin JIANG ; Wei-Ping LI ; Hong WU ; Xian-Xian ZHAO ; Yong-Wen QIN
Chinese Medical Journal 2009;122(6):655-658
BACKGROUNDPercutaneous aortic valve replacement is a promising strategy in the treatment of patients with aortic valve stenosis. And many kinds of valved stents have been implanted in selected patients worldwide. However, the clinical experience is still limited. We developed a W-model valved stent and evaluated the feasibility and safety of percutaneous implantation of the device in the native aortic valve position.
METHODSA self expanding nitinol stent with W-model, containing porcine pericardium valves in its proximal part, was implanted in six sheep by means of a 14 French catheter through the right common iliac artery under guidance of fluoroscopy. During stent deployment the original aortic valve was pushed against the aortic wall by the self expanding force of the stent while the new valve was expanded. These sheep were followed up shortly after procedure with supra-aortic angiogram and left ventriculography. Additionally, one sheep was sacrificed after the procedure for anatomic evaluation.
RESULTSIt was possible to replace the aortic valve in the beating heart in four sheep. The procedure failed in two sheep due to coronary orifice occlusion in one case and severe aortic valve regurgitation in the other case. One sheep was killed one hour after percutaneous aortic valve replacement for anatomic evaluation. There were no signs of damage of the aortic intima, or of obstruction of the coronary orifice.
CONCLUSIONSPercutaneous aortic valve replacement with a W-model valved stent in the beating heart is possible. Further studies are mandatory to assess safety and efficacy of this kind of valved stent in larger sample size and by longer follow-up period.
Animals ; Aortic Valve ; pathology ; surgery ; Aortic Valve Stenosis ; surgery ; Feasibility Studies ; Female ; Fluoroscopy ; Heart Valve Prosthesis Implantation ; instrumentation ; methods ; Male ; Sheep ; Stents ; adverse effects
4.Echocardiography in Transcatheter Aortic Valve Implantation and Mitral Valve Clip.
The Korean Journal of Internal Medicine 2012;27(3):245-261
Transcatheter aortic valve implantation and transcatheter mitral valve repair (MitraClip) procedures have been performed worldwide. In this paper, we review the use of two-dimensional and three-dimensional transesophageal echo for guiding transcatheter aortic valve replacement and mitral valve repair.
Aged
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Aged, 80 and over
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Aortic Valve Stenosis/*therapy/*ultrasonography
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Balloon Valvuloplasty
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Bioprosthesis
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*Cardiac Catheterization/adverse effects/instrumentation
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*Echocardiography
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Echocardiography, Doppler, Color
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Echocardiography, Three-Dimensional
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Echocardiography, Transesophageal
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Heart Valve Prosthesis
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Heart Valve Prosthesis Implantation/adverse effects/instrumentation/*methods
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Humans
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Mitral Valve Insufficiency/*therapy/*ultrasonography
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Predictive Value of Tests
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Prosthesis Design
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Severity of Illness Index
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Surgical Instruments
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Ultrasonography, Interventional/*methods
5.Long-term results of prosthetic mitral valve replacement with home-made tilting disc valve: a report of 125 cases.
Bao-ren ZHANG ; Zhi-yun XU ; Liang-jian ZOU ; Ju MEI ; Zhi-nong WANG ; Jia-hua HAO
Chinese Journal of Surgery 2003;41(4):253-256
OBJECTIVETo analyze the early and long-term results after mitral valve replacement for rheumatic valvular disease by using home-made tilting disc valve, and the determinant factors involved and subsequent therapies.
METHODSOne hundred and five patients, including 31 patients with rheumatic mitral stenosis, 92 patients with mixed mitral stenosis and regurgitation, and 2 patients with bacterial endocarditis, underwent prosthetic mitral valve replacement with home-made tilting disc valve from September 1978 to June 1982. Three patients had a history of mitral commissurotomy, and 5 patients had concomitant functional tricuspid regurgitation. All patients were operated on under cardiopulmonary bypass with implantation of 25 - 29 mm size home-made tilting disc valve prosthesis. The associated functional tricuspid lesions were treated at the same time with modified DeVega's valvuloplasty or Kays bicuspidate valvuloplasty.
RESULTSEleven patients died during the hospital stay with an early operative mortality of 8.8%. The major causes of the early death were low cardiac output syndrome (4 patients), respiratory failure (2), acute renal failure (2), extrinsic prosthesis dysfunction (1), ventricular arrhythmia (1), and left ventricular rupture (1). Ninety-eight survivors were followed up (total 1,162.2 years) for mean duration of 12.8 years. Eighty-nine patients (78%) survived over 10 years after operation, 58 (51%) over 15 years, and 55 (48%) over 20 years. There were 16 late deaths due to heart failure, anticoagulation related bleeding, thromboembolism and recurrence of rheumatic fever. The survival rates at 10 and 20 years were 82.3% and 51.1% respectively. Among the patients who survived over 20 years, 37 patients had the cardiac functional status returned to Class II, 13 Class III, and Class IV.
CONCLUSIONSSevere post-rheumatic valve deformity may occur in younger patients in China. Long-acting penicillin regimen given for 3 - 5 years for the prevention of rheumatic fever relapse is advocated. A low intensity anticoagulant regimen after mitral valve replacement is advisable in lowering the incidence of anticoagulant related bleeding, while optimizing sufficient protection against thromboembolic complication. Proper operative timing (e.g. when the patient is in sinus rhythm and in NYHA functional class II) is of great importance in achieving satisfied long-term results.
Adolescent ; Adult ; Anticoagulants ; administration & dosage ; adverse effects ; therapeutic use ; Female ; Follow-Up Studies ; Heart Valve Diseases ; etiology ; surgery ; Heart Valve Prosthesis Implantation ; instrumentation ; methods ; mortality ; Hemorrhage ; chemically induced ; prevention & control ; Humans ; Male ; Middle Aged ; Mitral Valve ; surgery ; Postoperative Complications ; prevention & control ; Retrospective Studies ; Rheumatic Heart Disease ; complications ; Secondary Prevention ; Survival Analysis ; Survival Rate ; Time Factors ; Treatment Outcome ; Young Adult
6.Protective effect of heparin-coated circuits on the platelets during cardiopulmonary bypass.
Kailun ZHANG ; Zhiwei HU ; Yunhai YANG ; Ruqing HUANG ; Huiming FAN ; Zongquan SUN
Journal of Huazhong University of Science and Technology (Medical Sciences) 2003;23(4):403-406
To observe the protective effect of heparin-coated circuits (HCC) on the platelet function during cardiopulmonary bypass (CPB), 23 patients with heart valve replacement were studied. The system heparin dose was 3 mg/kg in the control group (n = 15) and heparin-coated circuits in the HCC group (n = 8). Platelet count, alpha-granule membrane protein-140 (GMP-140) concentrations were determined before CPB, at 60 min of CPB, 30 and 60 min after protamine administration, first 12 h after CPB, respectively. At end of CPB the arterial filters in the circuits were observed by electron microscopy. The amount of first 12-h postoperative blood loss was measured. There was significant reduction in platelet loss during and after CPB in the HCC group in contrast to the control group during CPB (P<0.05). During the first 12 h, postoperative blood loss was reduced in the HCC group as compared with that in the control group (218+/-61 ml, vs. 332+/-118 ml, P<0.05). Electron microscopy showed that in the HCC group the filter meshes and their fringes were clear and fragments of floccules were occasionally seen, without adherent cells or only few adherent cells on their surfaces, whereas several cellular and fibrous components were found to adhere to the surfaces of the filter meshes in the control group. This study indicates that heparin-coated circuits might reduce the platelet loss and activation during CPB and improve hemocompatibility of cardiopulmonary bypass equipment.
Adult
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Anticoagulants
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metabolism
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pharmacology
;
therapeutic use
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Blood Coagulation
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drug effects
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Blood Platelets
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metabolism
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Cardiopulmonary Bypass
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instrumentation
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Coated Materials, Biocompatible
;
therapeutic use
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Extracorporeal Circulation
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Female
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Fibrinolytic Agents
;
metabolism
;
pharmacology
;
therapeutic use
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Heart Valve Prosthesis Implantation
;
Heparin
;
metabolism
;
pharmacology
;
therapeutic use
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Humans
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Male
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Middle Aged
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Mitral Valve Insufficiency
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surgery
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P-Selectin
;
metabolism
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Platelet Activation
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drug effects