-
Collected Works on Cardio-pulmonary... Dec 1975
Review
Topics: Anti-Arrhythmia Agents; Cardiac Catheterization; Diet, Sodium-Restricted; Digitalis Glycosides; Diuretics; Endocarditis, Bacterial; Fluoroscopy; Heart Valve Prosthesis; Humans; Phonocardiography; Postoperative Complications; Postpericardiotomy Syndrome; Surgical Wound Infection; Thromboembolism; Warfarin
PubMed: 770067
DOI: No ID Found -
Deutsche Medizinische Wochenschrift... Jun 1985From 1962 to 1984, 2460 prosthetic valve implantations in the heart were performed at the Department of Surgery of the University of Heidelberg. In addition to 2291... (Review)
Review
From 1962 to 1984, 2460 prosthetic valve implantations in the heart were performed at the Department of Surgery of the University of Heidelberg. In addition to 2291 primary surgical interventions, 169 re-interventions were carried out. 153 emergency operations were necessary. The frequency rate of operations increased continuously; 52% of the operations were performed at the aortic valve and 37% at the mitral valve. In 9% of the cases, two valves had to be replaced, and in 2% even three valve prostheses were implanted. The indications for re-intervention included prosthetic thromboses, paravalvular leakages and prosthetic valve endocarditis. The situations requiring emergency intervention differed from case to case. Early mortality, which had been initially high, could be considerably reduced due to increased experience in surgical technique, anaesthesia, intensive care and improved myocardial protection. The extent and quality of medical postoperative care will determine the success of medical rehabilitation and hence the future professional activity of the patient.
Topics: Adolescent; Adult; Aged; Aortic Valve; Child; Child, Preschool; Emergencies; Endocarditis; Female; Heart Valve Diseases; Heart Valve Prosthesis; Humans; Male; Middle Aged; Mitral Valve; Postoperative Complications; Prognosis; Reoperation; Thromboembolism; Tricuspid Valve
PubMed: 3891288
DOI: 10.1055/s-2008-1068944 -
Circulation Jan 1993
Topics: Equipment Failure; Heart Valve Diseases; Heart Valve Prosthesis; Humans; Thrombolytic Therapy; Thrombosis; Ultrasonography
PubMed: 8419018
DOI: 10.1161/01.cir.87.1.294 -
Anatolian Journal of Cardiology Sep 2022Intermittent malfunction is a rare but potentially serious complication of prosthetic heart valve replacement. This study aimed to describe the clinical features and...
BACKGROUND
Intermittent malfunction is a rare but potentially serious complication of prosthetic heart valve replacement. This study aimed to describe the clinical features and etiologic causes of patients with intermittent mechanical prosthetic heart valve dysfunction.
METHODS
Between 2010 and 2021, 16 patients who were evaluated in the echocardiography laboratory of Koşuyolu Training and Research Hospital with the diagnosis of intermittent malfunction of prosthetic valves were included in the study.
RESULTS
The evaluated patients consisted of 12 bi-leaflet mitral valve replacements and 2 mono-leaflet mitral valve replacements. The underlying causes of intermittent malfunction were classified as follows: residual chord (n=4), obstructive thrombus (n=2), non-obstructive thrombus (n=2), vegetation (n=2), pannus and obstructive thrombus coexistence (n=1), and solely pannus (n=1). One of the patients with mono-leaflet mitral valve replacements had pannus and obstructive thrombus. In the other patient with mono-leaflet mitral valve replacement, a stuck valve was observed in 1 of 12 beats secondary to arrhythmia. There were also 2 patients with aortic valve replacements. One patient had moderate aortic regurgitation due to prominent calcification and the other had moderate obstruction due to pannus. In the patient with pannus, a stuck leaflet was observed in 1 of 6 beats and moderate aortic regurgitation arose in 1 of 2 beats in the patient with calcification.
CONCLUSIONS
The intermittent stuck valve may have catastrophic outcomes. When making a treatment decision in these patients, assessing the degree of regurgitation or stenosis is essential. In particular, the frequency of entrapment should be taken into consideration when deciding the optimal therapy for intermittent prosthetic heart valve dysfunction.
Topics: Aortic Valve; Aortic Valve Insufficiency; Calcinosis; Heart Valve Prosthesis; Humans; Prosthesis Failure; Thrombosis
PubMed: 35949129
DOI: 10.5152/AnatolJCardiol.2022.1677 -
ASAIO Journal (American Society For... 2013Aortic stenosis is the most prevalent and life-threatening form of valvular heart disease. It is primarily treated via open-heart surgical valve replacement with either...
Aortic stenosis is the most prevalent and life-threatening form of valvular heart disease. It is primarily treated via open-heart surgical valve replacement with either a tissue or a mechanical prosthetic heart valve (PHV), each prone to degradation and thrombosis, respectively. Polymeric PHVs may be optimized to eliminate these complications, and they may be more suitable for the new transcatheter aortic valve replacement procedure and in devices like the total artificial heart. However, the development of polymer PHVs has been hampered by persistent in vivo calcification, degradation, and thrombosis. To address these issues, we have developed a novel surgically implantable polymer PHV composed of a new thermoset polyolefin called cross-linked poly(styrene-block-isobutylene-block-styrene), or xSIBS, in which key parameters were optimized for superior functionality via our device thrombogenicity emulation methodology. In this parametric study, we compared our homogeneous optimized polcymer PHV to a prior composite polymer PHV and to a benchmark tissue valve. Our results show significantly improved hemodynamics and reduced thrombogenicity in the optimized polymer PHV compared to the other valves. These results indicate that our new design may not require anticoagulants and may be more durable than its predecessor, and validate the improvement, toward optimization, of this novel polymeric PHV design.
Topics: Aortic Valve; Aortic Valve Stenosis; Computer Simulation; Heart Valve Prosthesis; Heart Valve Prosthesis Implantation; Hemodynamics; Humans; Platelet Activation; Polymers; Prosthesis Design; Reproducibility of Results; Thrombin
PubMed: 23644615
DOI: 10.1097/MAT.0b013e31828e4d80 -
The Journal of the Acoustical Society... Jun 1995People with serious heart conditions have had their expected life span extended considerably with the development of the prosthetic heart valve especially with the great...
People with serious heart conditions have had their expected life span extended considerably with the development of the prosthetic heart valve especially with the great strides made in valve design. Even though the designs are extremely reliable, the valves are mechanical and operating continuously over a long period; therefore structural failures can occur due to fatigue. In this paper acoustical signal processing techniques developed to process noisy heart valve sounds measured by a sensitive, surface contact microphone are discussed. Measuring heart sounds noninvasively in a noisy environment puts more demands on the signal processing to extract the desired signals from the noise. Heart valve sounds are short-duration (10-20 ms) transients and therefore nonstationary, requiring more sophisticated processing algorithms to achieve the desired signal-to-noise ratios. In this paper the preclassification signal processing is concentrated on exclusively. That is, the signal processing operations performed on the heart valve sounds prior to classification are discussed--a subject that will be developed in a future paper. Efforts are concentrated on the sounds corresponding to the heart valve opening cycle. Valve opening and closing acoustics present additional information about the outlet strut condition--the structural component implicated in valve failure. The importance of the opening sound for single leg separation detection/classification is based on the fact that as the valve opens, the disk passively hits the outlet strut. The opening sounds thus yield direct information about outlet strut condition with minimal amount of disturbance caused by the energy radiated from the disk. Hence the opening sound is a very desirable acoustic signal to extract. Unfortunately, the opening sounds have much lower signal levels relative to the closing sounds and therefore noise plays a more significant role than during the closing event. Because of this it is necessary to screen the sounds for outliers in order to insure a high sensitivity of classification. Because of the sharp resonances appearing in the corresponding spectrum, a parametric processing approach is developed based on an autoregressive model which was selected to characterize the sounds emitted by the Bjork-Shiley convexo-concave (BSCC) valve during opening cycle. First the basic signals and the extraction process used to create an ensemble of heart valve sounds are briefly discussed. Next, a beat monitor capable of rejecting beats that fail to meet an acceptance criteria based on their spectral content is developed.(ABSTRACT TRUNCATED AT 400 WORDS)
Topics: Acoustics; Heart Valve Prosthesis; Humans; Models, Cardiovascular; Sound Spectrography
PubMed: 7790647
DOI: 10.1121/1.412414 -
Academic Radiology Oct 1995A working valve phantom (WVP) that both exercises the valve occluder and simulates movements of the mitral annulus is described. It was designed to develop a method for...
RATIONALE AND OBJECTIVES
A working valve phantom (WVP) that both exercises the valve occluder and simulates movements of the mitral annulus is described. It was designed to develop a method for radiographic detection of a single broken leg of the two-legged Björk-Shiley convexo-concave (C/C) heart valve outlet strut.
METHODS
The WVP consists of a pneumatically driven left ventricular assist device immersed in 22 cm of water. Left ventricular assist device annulus movements are generated by systolic turgor and diastolic relaxation of the aortic outflow graft within limits set by the holding fixture design.
RESULTS
WVP images were comparable in attenuation, valve motion, and diagnostic sensitivity to clinical C/C valve images and were effective in assessing leaflet excursions in another valve model. Techniques developed in the WVP have proved successful in the clinical detection of C/C valves that have a single broken leg but that show normal function in all other tests.
CONCLUSION
The WVP can be a useful tool for developing refined radiographic assessments of prosthetic heart valves.
Topics: Heart Valve Prosthesis; Motion; Phantoms, Imaging; Prosthesis Failure
PubMed: 9419657
DOI: 10.1016/s1076-6332(05)80070-4 -
The Annals of Thoracic Surgery Sep 1994A multicenter prospective trial of the CarboMedics valve was initiated in July 1988. Twelve North American centers were included for the purpose of establishing the... (Clinical Trial)
Clinical Trial Review
A multicenter prospective trial of the CarboMedics valve was initiated in July 1988. Twelve North American centers were included for the purpose of establishing the safety and efficacy of this new rotatable, bileaflet, pyrolytic-Carbon prosthesis. The study included 786 patients (using 891 valves) enrolled between July 1988 and August 1992. There were 447 male and 339 female patients from ages 2 to 83 years. Of the 618 primary replacement operations (including double valves), 393 were aortic and 292 were mitral valve replacements. Mean follow-up time was 16.1 months; 94.7% of patients had completed documentation up to and including one year. New York Heart Association functional class was III or IV for 84.4% of patients preoperatively, and I and II in over 96% of patients for the first three postoperative years. Survival for the entire group was 93% (622) at 1 month, 89% (504) at 1 year, 87% (213) at 2 years, and 85% (41) at 3 years. There were no significant survival differences between primary and repeat replacements or between aortic, mitral, and double-valve replacements. Primary replacement patients with concomitant procedures (n = 241) had slightly decreased survival rates compared with those who underwent isolated procedures (isolated survival rate, 92% [98]; concomitant procedure survival rate, 81% [59] at 2 years; p = 0.002). There was no valve failure. Linearized rates (events per 100 patient-years) in primary replacement patients after 30 days included the following: thrombosis, 0.39; thromboembolism, 0.92; hemolysis, 0.53; anticoagulant-related hemorrhage, 2.36; paravalvular leak, 0.92; endocarditis, 0.53; reoperation, 0.92; and explantation, 0.66.(ABSTRACT TRUNCATED AT 250 WORDS)
Topics: Actuarial Analysis; Adolescent; Adult; Aged; Aged, 80 and over; Aortic Valve; Biocompatible Materials; Bioprosthesis; Carbon; Child; Child, Preschool; Female; Follow-Up Studies; Heart Function Tests; Heart Valve Diseases; Heart Valve Prosthesis; Humans; Linear Models; Male; Middle Aged; Mitral Valve; North America; Postoperative Care; Preoperative Care; Prospective Studies; Prosthesis Design; Reoperation; Survival Rate; Time Factors
PubMed: 7944682
DOI: 10.1016/0003-4975(94)90719-6 -
Heart (British Cardiac Society) Feb 2008
Topics: Anticoagulants; Heart Valve Prosthesis; Heparin, Low-Molecular-Weight; Humans; Postoperative Complications; Risk Factors; Thromboembolism
PubMed: 18195116
DOI: 10.1136/hrt.2007.115188 -
Artificial Organs May 2002
Topics: Aortic Valve; Cineradiography; Heart Valve Prosthesis; Hemodynamics; Humans; Prosthesis Design
PubMed: 12000434
DOI: 10.1046/j.1525-1594.2002.00909.x