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 ; Cardiac Catheterization ; Heart Valve Prosthesis ; Heart Valve Prosthesis Implantation ; adverse effects ; instrumentation ; methods ; Minimally Invasive Surgical Procedures ; methods ; Prosthesis Design ; Pulsatile Flow

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

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 ; Aged, 80 and over ; Aortic Valve Stenosis/*therapy/*ultrasonography ; Balloon Valvuloplasty ; Bioprosthesis ; *Cardiac Catheterization/adverse effects/instrumentation ; *Echocardiography ; Echocardiography, Doppler, Color ; Echocardiography, Three-Dimensional ; Echocardiography, Transesophageal ; Heart Valve Prosthesis ; Heart Valve Prosthesis Implantation/adverse effects/instrumentation/*methods ; Humans ; Mitral Valve Insufficiency/*therapy/*ultrasonography ; Predictive Value of Tests ; Prosthesis Design ; Severity of Illness Index ; Surgical Instruments ; Ultrasonography, Interventional/*methods

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