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1.
Space Weather ; 17(3): 419-437, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33363448

RESUMO

An interval of exceptional solar activity was registered in early September 2017, late in the decay phase of solar cycle 24, involving the complex Active Region 12673 as it rotated across the western hemisphere with respect to Earth. A large number of eruptions occurred between 4 and 10 September, including four associated with X-class flares. The X9.3 flare on 6 September and the X8.2 flare on 10 September are currently the two largest during cycle 24. Both were accompanied by fast coronal mass ejections and gave rise to solar energetic particle (SEP) events measured by near-Earth spacecraft. In particular, the partially occulted solar event on 10 September triggered a ground-level enhancement (GLE), the second GLE of cycle 24. A further, much less energetic SEP event was recorded on 4 September. In this work we analyze observations by the Advanced Composition Explorer (ACE) and the Geostationary Operational Environmental Satellites (GOES), estimating the SEP event-integrated spectra above 300 keV and carrying out a detailed study of the spectral shape temporal evolution. Derived spectra are characterized by a low-energy break at few/tens of MeV; the 10 September event spectrum, extending up to ~1 GeV, exhibits an additional rollover at several hundred MeV. We discuss the spectral interpretation in the scenario of shock acceleration and in terms of other important external influences related to interplanetary transport and magnetic connectivity, taking advantage of multipoint observations from the Solar Terrestrial Relations Observatory. Spectral results are also compared with those obtained for the 17 May 2012 GLE event.

2.
Nature ; 467(7317): 814-6, 2010 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-20944742

RESUMO

The peculiar object P/2010 A2 was discovered in January 2010 and given a cometary designation because of the presence of a trail of material, although there was no central condensation or coma. The appearance of this object, in an asteroidal orbit (small eccentricity and inclination) in the inner main asteroid belt attracted attention as a potential new member of the recently recognized class of main-belt comets. If confirmed, this new object would expand the range in heliocentric distance over which main-belt comets are found. Here we report observations of P/2010 A2 by the Rosetta spacecraft. We conclude that the trail arose from a single event, rather than a period of cometary activity, in agreement with independent results. The trail is made up of relatively large particles of millimetre to centimetre size that remain close to the parent asteroid. The shape of the trail can be explained by an initial impact ejecting large clumps of debris that disintegrated and dispersed almost immediately. We determine that this was an asteroid collision that occurred around 10 February 2009.

4.
J Small Anim Pract ; 65(1): 24-29, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37876317

RESUMO

OBJECTIVE: The purpose of this study was to evaluate a sit to stand test with the walk test for the identification of unilateral cranial cruciate ligament rupture in dogs. MATERIALS AND METHODS: Peak vertical force and vertical impulse were measured on a pressure-sensitive walkway, during a sit to stand test and walk test, and in 10 dogs with unilateral cranial cruciate ligament rupture and 18 non-lame dogs. Data collected were used to calculate symmetry indices (SI) of ipsilateral and contralateral hindlimbs (HL), diagonal limb pairs (DLP) and ipsilateral limb pairs (ILP). RESULTS: The symmetry indices of peak vertical force of HL during the walk test and sit to stand test were 100% and 90% sensitive for discriminating lame and non-lame dogs respectively. The symmetry indices of vertical impulse of HLs during the walk test and sit to stand test were 100% and 50% sensitive for discriminating lame and non-lame dogs respectively. Analysis of ipsilateral and diagonal limb pairs did not improve the discrimination in either test. The time taken to collect data from the sit to stand test data was shorter than for the walk test. CLINICAL SIGNIFICANCE: Whilst the sit to stand test required a shorter time for collection of data than the walk test, it did not accurately identify all dogs with lameness associated with CCLR, and thus has relatively limited clinical utility in its tested form.


Assuntos
Lesões do Ligamento Cruzado Anterior , Doenças do Cão , Cães , Animais , Ligamento Cruzado Anterior , Teste de Caminhada , Coxeadura Animal/diagnóstico , Doenças do Cão/diagnóstico , Marcha , Lesões do Ligamento Cruzado Anterior/diagnóstico , Lesões do Ligamento Cruzado Anterior/veterinária
5.
Ir Med J ; 106(6): 173-6, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23909153

RESUMO

Ireland has an ageing population and the elderly are over-represented in Emergency Departments (ED)--a quarter of these presentations resulting from falls. A prospective study design was employed using a convenience sample to profile elderly fallers referred for physiotherapy in ED. Forty-subjects were assessed over 14 weeks. Mean age was 84.88 years (s.d. 7.3) and 31 (77.5%) were female. All demonstrated slow walking speed and 26 (65%) demonstrated poor grip strength. A quarter of subjects reported fear of falling and 30 (75%) were classified as frail. Elderly fallers in ED are a frail group of socially vulnerable patients who demonstrate a risk of further falls. Osteoporosis had been diagnosed in 9 (22.5%) subjects--a low prevalence compared with international research, but 25 (62.5%) subjects had never had a DEXA scan. The prevalence of frailty in the sample of elderly fallers in this study was very high (75%).


Assuntos
Acidentes por Quedas , Força da Mão , Caminhada/fisiologia , Idoso , Idoso de 80 Anos ou mais , Serviço Hospitalar de Emergência , Medo , Feminino , Idoso Fragilizado , Hospitais de Ensino , Humanos , Irlanda , Masculino , Fatores de Risco , Tecnologia Assistiva
6.
Int J Surg Case Rep ; 104: 107944, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36822028

RESUMO

INTRODUCTION: Targeted radiotherapy, surgery, and localised disease progression can all result in fistulous tract formation in patients with a pelvic malignancy, in particular cervical or endometrial cancer. This report discusses a novel technique for palliative management of ureterovaginal fistulas in end-stage disease. PRESENTATION OF CASE REPORT: We report the case of a 37 year old female with metastatic cervical squamous cell carcinoma previously treated with chemoradiation who presented with progressive disease and secondary development of a symptomatic ureterovaginal fistula. DISCUSSION: This case report discusses the causes and sequalae of uretero-vaginal fistula formation, the role of the interventional radiology with regards to palliative intervention, and potential patient factors that can affect performance of such procedures. CONCLUSION: Interventional radiology plays an important role in palliative and symptomatic management of end stage malignant disease. Ureteric embolisation via a retrograde transurethral approach by way of an existing stent is a novel approach to access making the procedure easier for both the patient and radiologist.

7.
Int J Surg Case Rep ; 98: 107551, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36037638

RESUMO

INTRODUCTION AND IMPORTANCE: Xanthogranulomatous pyelonephritis (XGP) is an uncommon complication of chronic urinary tract infection, classically secondary to a chronic obstructive uropathy, resulting in destruction of renal parenchyma and a non-functioning kidney (Jha and Aeddula, 2022 [1]). This is rarely associated with nephrobronchial fistulation, with few published case reports in the literature to date. CASE PRESENTATION: We present the rare case of a 42-year-old female who was admitted to an Irish tertiary urology centre with abdominal pain, elevated inflammatory markers and an obstructive uropathy on initial imaging, with a new diagnosis of XGP. Initial management was with targeted intravenous antimicrobial therapy, percutaneous nephrostomy and perinephric drain insertion. The subsequent discovery of a nephrobronchial fistula later complicated the case, warranting plan for interval nephrectomy and fistula repair following prolonged medical management. We discuss the initial presentation, workup and image-guided approach to management. CLINICAL DISCUSSION: XGP is an uncommon sequela of chronic renal suppurative infection, and is usually associated with long-standing ureteric obstruction secondary to a staghorn calculus. Nephrobronchial fistulation is a rare complication of XGP, highlighting the significance of this case discussion. CONCLUSION: XGP should be considered in cases of suspected chronic pyelonephritis and may rarely lead to nephrobronchial fistulation. In cases of known XGP and pleural empyema, nephrobronchial fistulation should be considered as part of the differential diagnosis.

8.
Ir Med J ; 104(10): 311-2, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22256445

RESUMO

Thrombus formation is a recognised complication of IVC filter placement, however IVC and bilateral renal vein occlusion secondary to thrombus is much less common. We present a case of infrahepatic caval and bilateral renal vein occlusion secondary to thrombosis of a suprarenal IVC filter. With progressive clinical deterioration and failure of conservative medical management the patient underwent successful mechanical disruption and catheter directed thrombolysis.


Assuntos
Injúria Renal Aguda/etiologia , Cateterismo Periférico/métodos , Veias Renais , Terapia Trombolítica/métodos , Filtros de Veia Cava/efeitos adversos , Veia Cava Inferior , Trombose Venosa/terapia , Injúria Renal Aguda/fisiopatologia , Feminino , Fibrinolíticos/administração & dosagem , Humanos , Pessoa de Meia-Idade , Flebografia , Veias Renais/diagnóstico por imagem , Veias Renais/fisiopatologia , Tempo , Ativador de Plasminogênio Tecidual/administração & dosagem , Resultado do Tratamento , Veia Cava Inferior/diagnóstico por imagem , Veia Cava Inferior/fisiopatologia , Trombose Venosa/diagnóstico por imagem , Trombose Venosa/etiologia , Trombose Venosa/fisiopatologia
9.
Clin Exp Immunol ; 156(1): 149-60, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19210524

RESUMO

Adult human mesenchymal stromal or stem cells (MSC) can differentiate into a variety of cell types and are candidate cellular therapeutics in regenerative medicine. Surprisingly, these cells also display multiple potent immunomodulatory capabilities, including allosuppression, making allogeneic cell therapy a possibility. The exact mechanisms involved in regulatory T cell induction by allogeneic human MSC was examined, using purified CD4+ populations and well-characterized bone marrow-derived adult human MSC. Allogeneic MSC were shown to induce forkhead box P3 (FoxP3)+ and CD25+ mRNA and protein expression in CD4+ T cells. This phenomenon required direct contact between MSC and purified T cells, although cell contact was not required for MSC induction of FoxP3 expression in an unseparated mononuclear cell population. In addition, through use of antagonists and neutralizing antibodies, MSC-derived prostaglandins and transforming growth factor (TGF)-beta1 were shown to have a non-redundant role in the induction of CD4+CD25+FoxP3+ T cells. Purified CD4+CD25+ T cells induced by MSC co-culture expressed TGF-beta1 and were able to suppress alloantigen-driven proliferative responses in mixed lymphocyte reaction. These data clarify the mechanisms of human MSC-mediated allosuppression, supporting a sequential process of regulatory T cell induction involving direct MSC contact with CD4+ cells followed by both prostaglandin E(2) and TGF-beta1 expression. Overall, this study provides a rational basis for ongoing clinical studies involving allogeneic MSC.


Assuntos
Dinoprostona/imunologia , Fatores de Transcrição Forkhead/biossíntese , Células-Tronco Mesenquimais/imunologia , Linfócitos T Reguladores/imunologia , Fator de Crescimento Transformador beta1/imunologia , Comunicação Celular/imunologia , Células Cultivadas , Fatores de Transcrição Forkhead/genética , Regulação da Expressão Gênica/imunologia , Humanos , Subunidade alfa de Receptor de Interleucina-2/biossíntese , Subunidade alfa de Receptor de Interleucina-2/genética , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Fator de Crescimento Transformador beta1/genética
10.
Hernia ; 22(4): 697-705, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29556855

RESUMO

INTRODUCTION: Morgagni hernias rarely present in adult life and, thus, little data exist on the optimal method of surgical repair. The laparoscopic approach has grown in popularity since the first reported case in 1992. This article showcases a method for laparoscopic repair of Morgagni hernias using both primary closure and mesh reinforcement. OPERATIVE APPROACH: There were three obese women who presented in adulthood with cardiopulmonary symptoms; in all cases, the symptoms were attributable to local compressive effects of large Morgagni hernias. All three hernias were repaired laparoscopically, first by approximating the diaphragm to the fascia of the anterior abdominal wall, followed by insertion of a composite mesh, tacked to the diaphragm, to buttress the closure. All patients had excellent outcomes with symptom resolution. DISCUSSION: This case series describes a method of laparoscopic Morgagni hernia repair using primary closure reinforced with a mesh, with excellent postoperative outcomes. Others have described thoracic or open approaches. The authors feel that the method described herein is likely to reduce recurrence in a patient population who are often overweight or obese and, thus, have a high risk of this complication. Furthermore, we discuss all reported laparoscopic repair cases in the literature and highlight the paucity of evidence on the optimal approach.


Assuntos
Parede Abdominal/cirurgia , Diafragma/cirurgia , Hérnias Diafragmáticas Congênitas/cirurgia , Herniorrafia/métodos , Obesidade/complicações , Telas Cirúrgicas , Diafragma/anormalidades , Fáscia , Feminino , Hérnias Diafragmáticas Congênitas/complicações , Humanos , Laparoscopia , Pessoa de Meia-Idade , Procedimentos de Cirurgia Plástica/métodos
11.
Oper Dent ; 43(5): 467-471, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29570028

RESUMO

Given the increasing incidence of root caries in the elderly population, clinicians frequently must isolate and restore subgingival preparations. This article demonstrates a technique utilizing a modified Tofflemire matrix band that creates a preparation free of crevicular fluid and blood for restoration with resin-modified glass ionomer cement.


Assuntos
Restauração Dentária Permanente/métodos , Bandas de Matriz , Cárie Radicular/cirurgia , Restauração Dentária Permanente/instrumentação , Humanos , Incisivo/cirurgia , Masculino , Pessoa de Meia-Idade
12.
J R Army Med Corps ; 153 Suppl 1: 44-7; discussion 48-9, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18214085

RESUMO

In the recent Falklands campaign four Army Field Surgical Teams were deployed in the two phases of the war. They functioned as Advanced Surgical Centres and operated on 233 casualties. There were 3 deaths. The patterns of wounding and the methods of casualty management are discussed and compared with other recent campaigns.


Assuntos
Hospitais Militares/organização & administração , Hospitais de Emergência , Medicina Militar/história , Militares , Guerra , Ferimentos por Arma de Fogo/cirurgia , Resgate Aéreo , Ilhas Malvinas , História do Século XX , Humanos , Medicina Militar/métodos , Transporte de Pacientes , Reino Unido/epidemiologia , Ferimentos por Arma de Fogo/mortalidade
13.
Tech Vasc Interv Radiol ; 9(2): 69-76, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17482103

RESUMO

Every interventional procedure can result in infective complications. Generally the incidence is low; however, with newer and more aggressive techniques the infection risk is more prevalent and can result in serious adverse outcomes to our patients. Antibiotic prophylaxis has become commonplace; however, there is little controlled data to underpin our regimens and most choices are based on surgical practice and anecdotal evidence. The rise of antibiotic resistance and treatment of many immunocompromised patients further compounds the difficulties faced. The purpose of this article was to examine the evidence that is presented regarding antibiotic prophylaxis in interventional radiology and highlight how we integrate this into our daily practice. In particular we will focus on evolving procedures and techniques that are associated with a high incidence of infection.


Assuntos
Antibioticoprofilaxia , Radiografia Intervencionista , Infecção da Ferida Cirúrgica/prevenção & controle , Humanos , Fatores de Risco
14.
J Prev Alzheimers Dis ; 3(2): 75-84, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-29210443

RESUMO

BACKGROUND: ACC-001 is an investigational therapeutic vaccine designed to elicit antibodies against the N-terminal peptide 1-7 of the amyloid-beta peptide, believed to be important in the pathogenesis of Alzheimer's disease. OBJECTIVES: To evaluate safety, immunogenicity, impact on brain amyloid, and other exploratory endpoints in participants receiving ACC-001. DESIGN: Randomized, phase 2, interventional study. TRIAL REGISTRATION: Clinicaltrials.gov ID NCT01227564. PARTICIPANTS: Individuals with early Alzheimer's disease (Mini-Mental State Examination scores ≥25, a global Clinical Dementia Rating of 0.5, and evidence of elevated baseline brain amyloid burden). INTERVENTION: Participants were randomized to ACC-001 3 µg or 10 µg with QS-21 adjuvant (50 µg), or placebo. MEASUREMENTS: The primary endpoint was change in brain amyloid burden by 18F-florbetapir positron emission tomography in composite cortical standard uptake value ratio. RESULTS: A total of 63 participants were randomized and 51 completed the study. At week 104, no significant differences were observed in 18F-florbetapir positron emission tomography composite cortical standard uptake value ratio between either ACC-001 dose compared with placebo. In both ACC-001 + QS-21 treatment groups, following the initial immunization, the anti-amyloid-beta geometric mean titers increased after each subsequent vaccination and then declined, with less apparent decline after the later compared with earlier immunizations. The majority of treatment-emergent adverse events in the ACC-001 + QS-21 groups were injection site reactions, which occurred at a greater rate in active treatment groups than in the placebo group. No amyloid-related imaging abnormalities of edema or effusion were reported. CONCLUSION: No statistically significant differences were observed between groups in the change from baseline brain amyloid burden despite apparently robust systemically measured anti-amyloid-beta antibody response at both dose levels. Insufficient antibody titers, poor quality immune response, short duration of treatment, or small sample size may have resulted in these findings. The safety and tolerability profile was acceptable.

15.
Exp Hematol ; 11(9): 891-8, 1983 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-6688995

RESUMO

The extrarenal production of erythropoietin (Ep) was measured in young adolescent rats following exchange-transfusion with normal rat plasma or the whole blood replacement fluid, Fluosol-43. In the plasma-transfused anephric groups, the peak extrarenal Ep response to the severe degree of anemic hypoxia represented 23% of that evoked in renal-intact groups. In contrast, the peak extrarenal production of Ep in Fluosol-transfused renoprival groups was almost equal to those serum Ep levels produced in renal-intact groups. Histological studies revealed significant fluorocarbon uptake by hepatic macrophages that coincided with the time of peak production of Ep. Thus, while intense levels of hypoxia are required to stimulate the extrarenal production of Ep, these data suggest that as Fluosol-43 is taken up by the hepatic macrophages, Ep production by these cells is stimulated.


Assuntos
Eritropoetina/biossíntese , Transfusão Total , Rim/metabolismo , Fígado/metabolismo , Animais , Eritropoetina/análogos & derivados , Eritropoetina/sangue , Fluorocarbonos/administração & dosagem , Fluorocarbonos/uso terapêutico , Rim/fisiopatologia , Fígado/citologia , Fígado/fisiologia , Macrófagos/fisiologia , Masculino , Camundongos , Nefrectomia , Troca Plasmática , Ratos
16.
Br J Radiol ; 88(1049): 20140627, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25761211

RESUMO

OBJECTIVE: In 2011, the International Commission on Radiological Protection (ICRP) recommended a substantial reduction in the equivalent dose limit for the lens of the eye, in line with a reduced threshold of absorbed dose for radiation-induced cataracts. This is of particular relevance in interventional radiology (IR) where it is well established that staff doses can be significant, however, there is a lack of data on IR eye doses in terms of Hp(3). Hp(3) is the personal dose equivalent at a depth of 3 mm in soft tissue and is used for measuring lens dose. We aimed to obtain a reliable estimate of eye dose to IR operators. METHODS: Lens doses were measured for four interventional radiologists over a 3-month period using dosemeters specifically designed to measure Hp(3). RESULTS: Based on their typical workloads, two of the four interventional radiologists would exceed the new ICRP dose limit with annual estimated doses of 31 and 45 mSv to their left eye. These results are for an "unprotected" eye, and for IR staff who routinely wear lead glasses, the dose beneath the glasses is likely to be significantly lower. Staff eye dose normalized to patient kerma-area product and eye dose per procedure have been included in the analysis. CONCLUSION: Eye doses to IR operators have been established using a dedicated Hp(3) dosemeter. Estimated annual doses have the potential to exceed the new ICRP limit. ADVANCES IN KNOWLEDGE: We have estimated lens dose to interventional radiologists in terms of Hp(3) for the first time in an Irish hospital setting.


Assuntos
Dispositivos de Proteção dos Olhos , Exposição Ocupacional/prevenção & controle , Exposição Ocupacional/normas , Doses de Radiação , Radiologia Intervencionista , Fluoroscopia , Humanos , Irlanda , Radiometria , Carga de Trabalho
17.
Am J Psychiatry ; 158(5): 712-7, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11329391

RESUMO

OBJECTIVE: The capacity of persons with Alzheimer's disease or other neuropsychiatric disorders for giving consent to participate in research has come under increasing scrutiny. While instruments for measuring abilities related to capacity have been developed, how they should be used to categorize subjects as capable or incapable is not clear. A criterion validation study was carried out to help address this question. METHOD: The authors measured the ability of 37 subjects with mild-to-moderate Alzheimer's disease and 15 elderly comparison subjects to provide consent for participation in a hypothetical clinical trial. Using the judgment of three experts as the criterion standard, the authors performed a receiver operator characteristic analysis for the capacity ability measures from the MacArthur Competence Assessment Tool-Clinical Research VERSION: The results were compared with categorizations of capacity status that were based on normative values. RESULTS: While most comparison subjects scored perfectly on all measures of the competence assessment tool, the majority of the group with Alzheimer's disease showed significant decision-making impairment. Thresholds based on normative values resulted in 84% (N=31) of the Alzheimer's disease subjects being rated as incapable on at least one ability; thresholds based on expert judgment resulted in 62% (N=23) failing to meet cutoff scores on at least one ability. CONCLUSIONS: Even relatively mild Alzheimer's disease significantly impairs consent-giving capacity. But differentiating capable from incapable subjects remains an issue despite the aid of standardized tools. More research is needed to understand the relationship between subject factors (performance on ability measures) and categorical judgments about their capacity.


Assuntos
Doença de Alzheimer/diagnóstico , Ensaios Clínicos como Assunto , Consentimento Livre e Esclarecido , Competência Mental/classificação , Seleção de Pacientes , Idoso , Doença de Alzheimer/classificação , Doença de Alzheimer/psicologia , Feminino , Psiquiatria Legal/instrumentação , Psiquiatria Legal/estatística & dados numéricos , Avaliação Geriátrica/estatística & dados numéricos , Humanos , Masculino , Competência Mental/normas , Escalas de Graduação Psiquiátrica/estatística & dados numéricos , Psicometria , Curva ROC , Projetos de Pesquisa , Sensibilidade e Especificidade , Índice de Gravidade de Doença
18.
Am J Med ; 78(3): 375-84, 1985 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-3976700

RESUMO

Observations on the atrial systolic murmur, the tricuspid opening snap, and the right atrial pressure pulse of tricuspid stenosis are presented, based on catheter manometer intracardiac sound and pressure recordings in five patients with hemodynamically significant tricuspid stenosis. The manometer-recorded right atrial pressure pulse of tricuspid stenosis differed from the normal, with (1) elevation of right atrial pressure, (2) different morphologic features (tall, spiky A wave complete before C; small V wave with an interruption, the tricuspid opening snap notch at termination of the gradual Y descent; a diastolic plateau, the relatively flat diastolic segment of the right atrial pressure pulse following the tricuspid opening snap notch prior to the next A wave), and (3) the relative lack of right atrial pressure and right atrial pressure pulse response with normal respiration. The atrial systolic murmur, recorded in the right ventricular inflow tract, was complete by S1; the crescendo-decrescendo atrial systolic murmur configuration paralleled the right ventricular-right atrial diastolic pressure gradient at the time of the atrial A wave. The right atrial contraction-relaxation process, as reflected by the right atrial A wave ascent and descent, was complete at the onset of ventricular systole with P-R intervals of 170 to 200 msec. Thus, the timing and configuration of the atrial systolic murmur reflected the timing and completion of the right atrial contraction-relaxation process prior to the onset of right ventricular systole and the configuration of the tricuspid diastolic pressure gradient. The tricuspid opening snap was recorded in the right ventricular inflow tract and occurred at the time of a notch at the termination of the Y descent of the right atrial pressure pulse V wave, while right atrial pressure exceeded right ventricular pressure. The sound-pressure events were consistent with angiographic and echocardiographic studies, which showed doming or ballooning of the mobile, fused, stenotic tricuspid valve into the right ventricle during the Y descent of the right atrial pressure pulse. The tricuspid opening snap occurred at the time of the termination of the diastolic movement of the fused tricuspid unit into the right ventricle. These observations are presented within the framework of previous studies in order to trace the development of medical ideas about the pathophysiologic basis for the sound and pressure events of tricuspid stenosis.


Assuntos
Auscultação Cardíaca , Sopros Cardíacos , Pulso Arterial , Estenose da Valva Tricúspide/fisiopatologia , Adolescente , Pressão Sanguínea , Cateterismo Cardíaco , Eletrocardiografia , Feminino , Átrios do Coração , Auscultação Cardíaca/história , Sopros Cardíacos/história , Ventrículos do Coração , História do Século XVIII , História do Século XX , Humanos , Masculino , Manometria , Fonocardiografia , Estenose da Valva Tricúspide/história
19.
Am J Cardiol ; 58(9): 762-7, 1986 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-3766417

RESUMO

Little information is available concerning the progression of mild to severe mitral regurgitation (MR) in patients with mitral valve prolapse (MVP). This study reports 86 patients, average age 60 years, who presented with cardiac symptoms, precordial systolic murmur, severe MR and a high incidence of MVP on echocardiography (57 of 75 [75%] ) and left ventriculography (61 of 84 [73%] ). Seventy-five surgically excised mitral valves appeared grossly enlarged and floppy. Histologic studies showed extensive myxomatous changes throughout the leaflets and chordae. Eighty patients had had precordial murmurs first described at average age 34 years, but the average age at which symptoms of cardiac dysfunction appeared was 59. However, once symptoms developed, mitral valve surgery was required within 1 year in 67 of 76 patients who had undergone surgery. Atrial fibrillation, present in 48 of 86 patients (56%), or ruptured chordae tendineae, present in 39 of 76 patients (51%), may have contributed to this rapid progression and deterioration. Additionally, 13 patients had a remote history of documented infective endocarditis. Twenty-eight patients had at least 1 type of serial clinical evaluation that indicated progressive MR in all 28 patients on the basis of changing auscultatory findings (24 of 26), progressive radiographic cardiomegaly (24 of 25), echocardiographic left atrial enlargement (4.3 to 5 cm in 11 patients) and angiographically worsening MR (14 of 15). Twenty-four of these patients had evidence of MVP on at least 1 of their initial studies. Thus, mild MR due to MVP and myxomatous mitral valves is a progressive disease in some patients with MVP.


Assuntos
Insuficiência da Valva Mitral/diagnóstico , Prolapso da Valva Mitral/diagnóstico , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
20.
Am J Cardiol ; 52(5): 534-9, 1983 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-6613875

RESUMO

Sixty-two patients diagnosed as having mitral valve prolapse, 60 to 81 years old, presented with disabling chest pain (20), symptoms of arrhythmias including palpitations and syncope (16), or mitral regurgitation (MR) with symptoms of congestive heart failure (26). The diagnosis of MVP was made on the basis of a combination of classic auscultatory, echocardiographic and angiographic findings. Thirteen of the 20 patients with chest pain had normal coronary angiograms and 7 had significant coronary artery disease (CAD). Patients with CAD could not be differentiated by clinical presentation alone. Furthermore, the incidence and types of arrhythmias, the presence of a positive stress test, and hemodynamic findings were similar in all patients in this group whether or not CAD was present. The 16 patients with palpitations had a broad spectrum of rhythm disorders, including both supraventricular and ventricular arrhythmias. Two patients had prehospital "sudden death" and 2 others had systemic emboli. Twenty-one of the 26 patients with MR had valve surgery. Intraoperatively the valves were described as enlarged, floppy and with redundant leaflets. Histologic examination showed extensive "myxomatous" changes throughout the valve leaflets. Thus, mitral valve prolapse is a cause of symptomatic heart disease in the elderly. It has a predictable pattern of clinical presentation and should be considered in the differential diagnosis of older patients with disabling chest pain and arrhythmias and as the cause of progressive or severe MR.


Assuntos
Prolapso da Valva Mitral/diagnóstico , Idoso , Angiografia , Arritmias Cardíacas/diagnóstico , Cateterismo Cardíaco , Diagnóstico Diferencial , Ecocardiografia , Feminino , Auscultação Cardíaca , Insuficiência Cardíaca/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Insuficiência da Valva Mitral/diagnóstico , Dor , Tórax
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