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1.
West Indian Med J ; 62(6): 504-9, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24756735

RESUMEN

OBJECTIVE: This study evaluated treatment strategies for head and neck cancers in a predominantly African American population. METHODS: Data were collected utilizing medical records and the tumour registry at the Howard University Hospital. Kaplan-Meier method was used for survival analysis and Cox proportional hazards regression analysis predicted the hazard of death. RESULTS: Analysis revealed that the main treatment strategy was radiation combined with platinum for all stages except stage I. Cetuximab was employed in only 1% of cases. Kaplan-Meier analysis revealed stage II patients had poorer outcome than stage IV while Cox proportional hazard regression analysis (p = 0.4662) showed that stage I had a significantly lower hazard of death than stage IV (HR = 0.314; p = 0.0272). Contributory factors included tobacco and alcohol but body mass index (BMI) was inversely related to hazard of death. CONCLUSIONS: There was no difference in survival using any treatment modality for African Americans.


Asunto(s)
Negro o Afroamericano , Carcinoma de Células Escamosas/etnología , Carcinoma de Células Escamosas/terapia , Neoplasias de Cabeza y Cuello/etnología , Neoplasias de Cabeza y Cuello/terapia , Neoplasias Laríngeas/etnología , Neoplasias Faríngeas/etnología , Anciano , Carcinoma de Células Escamosas/mortalidad , Femenino , Neoplasias de Cabeza y Cuello/mortalidad , Humanos , Estimación de Kaplan-Meier , Neoplasias Laríngeas/terapia , Masculino , Persona de Mediana Edad , Neoplasias Faríngeas/terapia , Modelos de Riesgos Proporcionales , Estudios Retrospectivos , Carcinoma de Células Escamosas de Cabeza y Cuello
2.
Lancet ; 355(9222): 2199-203, 2000 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-10881893

RESUMEN

BACKGROUND: Whether routine implantation of coronary stents is the best strategy to treat flow-limiting coronary stenoses is unclear. An alternative approach is to do balloon angioplasty and provisionally use stents only to treat suboptimum results. We did a multicentre trial to compare the outcomes of patients treated with these strategies. METHODS: We randomly assigned 479 patients undergoing single-vessel coronary angioplasty routine stent implantation or initial balloon angioplasty and provisional stenting. We followed up patients for 6 months to determine the composite rate of death, myocardial infarction, cardiac surgery, and target-vessel revascularisation. RESULTS: Stents were implanted in 227 (98.7%) of the patients assigned routine stenting. 93 (37%) patients assigned balloon angioplasty had at least one stent placed because of suboptimum angioplasty results. At 6 months the composite endpoint was significantly lower in the routine stent strategy (14 events, 6.1%) than with the strategy of balloon angioplasty with provisional stenting (37 events, 14.9%, p=0.003). The cost of the initial revascularisation procedure was higher than when a routine stent strategy was used (US$389 vs $339, p<0.001) but at 6 months, average per-patient hospital costs did not differ ($10,206 vs $10,490). Bootstrap replication of 6-month cost data showed continued economic benefit of the routine stent strategy. INTERPRETATION: Routine stent implantation leads to better acute and long-term clinical outcomes at a cost similar to that of initial balloon angioplasty with provisional stenting.


Asunto(s)
Angioplastia Coronaria con Balón , Enfermedad Coronaria/terapia , Stents , Adulto , Anciano , Anciano de 80 o más Años , Angioplastia Coronaria con Balón/economía , Procedimientos Quirúrgicos Cardíacos , Distribución de Chi-Cuadrado , Femenino , Estudios de Seguimiento , Costos de la Atención en Salud , Costos de Hospital , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/etiología , Modelos de Riesgos Proporcionales , Calidad de Vida , Retratamiento , Stents/economía , Tasa de Supervivencia , Resultado del Tratamiento
3.
Am J Cardiol ; 85(11): 1292-6, 2000 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-10831942

RESUMEN

Although cardiac surgery is performed in approximately 10% of acute myocardial infarction (AMI) patients undergoing a primary percutaneous transluminal coronary angioplasty (PTCA) reperfusion strategy before discharge, the indications for and timing of operative revascularization, and the short- and long-term outcomes after surgery have not been characterized. In the prospective, controlled Primary Angioplasty in Myocardial Infarction-2 trial, cardiac catheterization was performed in 1,100 patients within 12 hours of onset of AMI at 34 centers, followed by primary PTCA when appropriate. Cardiac surgery was performed before hospital discharge in 120 patients (10.9%), electively in 42.6%, and on an urgent or emergent basis in 57.4%. Surgery was performed in 6.1% of 982 patients after primary PTCA (although emergently for failed PTCA in only 4 cases [0.4%]), and in 53 of 118 patients (44.9%) not undergoing primary PTCA. Patients requiring surgery were older, and more frequently had diabetes and 3-vessel disease than those managed nonoperatively. Internal mammary artery grafts were placed in only 31% of patients. In-hospital mortality was 6.4% in patients undergoing urgent/emergent surgery, 2.0% after elective surgery, and 2.6% in patients not undergoing surgery (p = NS). After multivariate correction for baseline risk factors, early and late survival free of reinfarction were similar in patients undergoing versus not undergoing in-hospital cardiac surgery. Thus, the appropriate use of coronary artery bypass graft surgery in the peri-infarction period is an integral component of the primary PTCA approach, and is frequently used to optimize the prognosis of a high-risk AMI cohort with unfavorable baseline features. The implications for the performance of primary PTCA in AMI at centers without on-site surgical facilities are discussed.


Asunto(s)
Angioplastia Coronaria con Balón , Puente de Arteria Coronaria , Infarto del Miocardio/terapia , Anciano , Estudios de Cohortes , Supervivencia sin Enfermedad , Femenino , Mortalidad Hospitalaria , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/mortalidad , Pronóstico , Estudios Prospectivos , Recurrencia , Retratamiento , Tasa de Supervivencia
4.
J Am Coll Cardiol ; 35(3): 605-11, 2000 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-10716461

RESUMEN

OBJECTIVES: We sought to characterize the presenting characteristics of patients with previous coronary artery bypass graft surgery (CABG) and acute myocardial infarction (AMI) and to determine the angiographic success rate and clinical outcomes of a primary percutaneous transluminal coronary angioplasty (PTCA) strategy. BACKGROUND: Patients who have had previous CABG and AMI comprise a high risk group with decreased reperfusion success and increased mortality after thrombolytic therapy. Little is known about the efficacy of primary PTCA in AMI. METHODS: Early cardiac catheterization was performed in 1,100 patients within 12 h of onset of AMI at 34 centers in the prospective, controlled Second Primary Angioplasty in Myocardial Infarction trial (PAMI-2), followed by primary PTCA when appropriate. Data were collected by independent study monitors, end points were adjudicated and films were read at an independent core laboratory. RESULTS: Of 1,100 patients with AMI, 58 (5.3%) had undergone previous CABG. The infarct-related vessel in these patients was a bypass graft in 32 patients (55%) and a native coronary artery in 26 patients. Compared with patients without previous CABG, patients with previous CABG were older and more frequently had a previous myocardial infarction and triple-vessel disease. Coronary angioplasty was less likely to be performed when the infarct-related vessel was a bypass graft rather than a native coronary artery (71.9% vs. 89.8%, p = 0.001); Thrombolysis in Myocardial Infarction trial (TIMI) flow grade 3 was less frequently achieved (70.2% vs. 94.3%, p < 0.0001); and in-hospital mortality was increased (9.4% vs. 2.6%, p = 0.02). As a result, mortality at six months was 14.3% versus 4.1% in patients with versus without previous CABG (p = 0.001). By multivariate analysis, independent determinants of late mortality in the entire study group were advanced age, triple-vessel disease, Killip class and post-PTCA TIMI flow grade <3. CONCLUSIONS: Reperfusion success of a primary PTCA strategy in patients with previous CABG, although favorable with respect to historic control studies, is reduced as compared with that in patients without previous CABG. New approaches are required to treat patients with previous CABG and AMI, especially when the infarct-related vessel is a diseased saphenous vein graft.


Asunto(s)
Angioplastia Coronaria con Balón , Angiografía Coronaria , Puente de Arteria Coronaria , Infarto del Miocardio/terapia , Anciano , Cateterismo Cardíaco , Femenino , Mortalidad Hospitalaria , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/diagnóstico por imagen , Infarto del Miocardio/mortalidad , Activadores Plasminogénicos/uso terapéutico , Estudios Prospectivos , Recurrencia , Terapia Trombolítica , Resultado del Tratamiento , Activador de Plasminógeno de Tipo Uroquinasa/uso terapéutico
5.
Circulation ; 99(12): 1548-54, 1999 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-10096929

RESUMEN

BACKGROUND: Restenosis has been reported in as many as 50% of patients within 6 months after PTCA in acute myocardial infarction (AMI), which necessitates repeat target-vessel revascularization (TVR) in approximately 20% of patients during this time period. Routine (primary) stent implantation after PTCA has the potential to further improve late outcomes. METHODS AND RESULTS: Primary stenting was performed as part of a prospective study in 236 consecutive patients without contraindications who presented with AMI of <12 hours' duration at 9 international centers. A mean of 1.4+/-0.7 stents were implanted per patient (97% Palmaz-Schatz) at 17.3+/-2.4 atm. During a clinical follow-up period of 7.4+/-2.6 months, death occurred in 4 patients (1.7%), reinfarction occurred in 5 patients (2.1%), and TVR was required in 26 patients (11.1%). By Cox regression analysis, small reference-vessel diameter and the number of stents implanted were the strongest determinants of TVR. Angiographic restenosis occurred in 27.5% of lesions. By multiple logistic regression analysis, the number of stents implanted and the absence of thrombus on the baseline angiogram were independent determinants of binary restenosis. CONCLUSIONS: A strategy of routine stent implantation during mechanical reperfusion of AMI is safe and is associated with favorable event-free survival and low rates of restenosis compared with primary PTCA alone.


Asunto(s)
Angioplastia Coronaria con Balón , Angiografía Coronaria , Infarto del Miocardio/terapia , Stents , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Estudios Prospectivos , Recurrencia , Análisis de Regresión
6.
J Interv Card Electrophysiol ; 2(2): 175-9, 1998 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9870010

RESUMEN

Pacemakers are frequently implanted, yet accurate prospective data on implant complications are limited. Elderly patients may be at increased risk of implant complications and are increasingly being referred for pacemaker implantation. The purpose of the present analysis was to define the incidence and possible predictors of serious complications of dual chamber permanent pacemaker implantation in the elderly. Therefore, we sought to prospectively identify the incidence and predictors of pacemaker implant complications in a large multicenter trial involving patients receiving a dual chamber pacemaker. The Pacemaker Selection in the Elderly (PASE) study was a prospective trial designed to evaluate quality of life in dual chamber pacemaker recipients age 65 years or older randomized to DDDR versus VVIR programming. In addition to being age 65 years or older, patients enrolled in this study were in normal sinus rhythm, and had standard indications for permanent pacemaker implantation. All patients received dual chamber pacemakers and were randomized to DDDR versus VVIR pacing. Pacemaker implant complications were collected on standardized forms which were completed at pacemaker implantation and during follow-up appointments. In this study of 407 patients, there were 26 complications occurring in 25 patients (6.1%). The most frequent complication was lead dislodgment which occurred in 9 patients. This was followed by pneumothorax (8 patients) and cardiac perforations (4 patients). In 18 patients (4.4%) repeat surgical procedures (including chest tubes) were required. Complications were noted prior to discharge in only 18 patients. There were no significant predictors of overall complications. Pneumothorax was more frequent in patients > or = 75 years old, and was observed only in patients with subclavian venous access. In conclusion, complications from pacemaker implantation in the elderly are seen in 6.1% of patients and 4.4% of patients require a repeat surgical procedure. Other than advanced age and lower weight predicting for pneumothorax, there are no significant clinical predictors of complications.


Asunto(s)
Marcapaso Artificial/efectos adversos , Factores de Edad , Anciano , Peso Corporal , Estimulación Cardíaca Artificial/efectos adversos , Estimulación Cardíaca Artificial/métodos , Cateterismo Venoso Central/instrumentación , Tubos Torácicos , Diseño de Equipo , Falla de Equipo , Femenino , Estudios de Seguimiento , Predicción , Lesiones Cardíacas/etiología , Frecuencia Cardíaca/fisiología , Humanos , Incidencia , Masculino , Neumotórax/etiología , Estudios Prospectivos , Calidad de Vida , Reoperación , Factores de Riesgo , Factores Sexuales , Vena Subclavia
7.
J Am Coll Cardiol ; 31(1): 23-30, 1998 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9426013

RESUMEN

OBJECTIVES: The goals of this study were to examine the safety and feasibility of a routine (primary) stent strategy in acute myocardial infarction (AMI). BACKGROUND: Limitations of reperfusion by primary percutaneous transluminal coronary angioplasty (PTCA) in AMI include in-hospital recurrent ischemia or reinfarction in 10% to 15% of patients, restenosis in 37% to 49% and late infarct-related artery reocclusion in 9% to 14%. By lowering the residual stenosis and sealing dissection planes created by PTCA, primary stenting may further improve short- and long-term outcomes after mechanical reperfusion. METHODS: Three hundred twelve consecutive patients treated with primary PTCA for AMI at nine international centers were prospectively enrolled. After PTCA, stenting was attempted in all eligible lesions (vessel size 3.0 to 4.0 mm; lesion length < or = 2 stents; and the absence of giant thrombus burden after PTCA, major side branch jeopardy or excessive proximal tortuosity or calcification). Patients with stents were treated with aspirin, ticlopidine and a 60-h tapering heparin regimen. RESULTS: Stenting was attempted in 240 (77%) of 312 patients, successfully in 236 (98%), with Thrombolysis in Myocardial Infarction grade 3 flow restored in 230 patients (96%). Patients with stents had low rates of in-hospital death (0.8%), reinfarction (1.7%), recurrent ischemia (3.8%) and predischarge target vessel revascularization for ischemia (1.3%). At 30-day follow-up, no additional deaths or reinfarctions occurred among patients with stents, and target vessel revascularization was required in only one additional patient (0.4%). CONCLUSIONS: Primary stenting is safe and feasible in the majority of patients with AMI and results in excellent short-term outcomes.


Asunto(s)
Infarto del Miocardio/terapia , Stents , Anciano , Angiografía Coronaria , Circulación Coronaria , Estudios de Factibilidad , Femenino , Mortalidad Hospitalaria , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/mortalidad , Proyectos Piloto , Estudios Prospectivos , Flujo Sanguíneo Regional
8.
J Am Coll Cardiol ; 29(7): 1459-67, 1997 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9180105

RESUMEN

OBJECTIVES: A large, international, multicenter, prospective, randomized trial was performed to determine the role of prophylactic intraaortic balloon pump (IABP) counterpulsation after primary percutaneous transluminal coronary angioplasty (PTCA) in acute myocardial infarction (AMI). BACKGROUND: Previous studies have suggested that routine IABP use after primary PTCA reduces infarct-related artery reocclusion, augments myocardial recovery and improves clinical outcomes. METHODS: Cardiac catheterization was performed in 1,100 patients within 12 h of onset of AMI at 34 clinical centers. Clinical and angiographic variables were used to stratify patients undergoing primary PTCA into high and low risk groups. High risk patients were then randomized to 36 to 48 h of IABP (n = 211) or traditional care (n = 226). The study had 80% power to detect a reduction in the primary end point from 30% to 20%. RESULTS: There was no significant difference in the predefined primary combined end point of death, reinfarction, infarct-related artery reocclusion, stroke or new-onset heart failure or sustained hypotension in patients treated with an IABP versus those treated conservatively (28.9% vs. 29.2%, p = 0.95). The IABP strategy conferred modest benefits in reduction of recurrent ischemia (13.3% vs. 19.6%, p = 0.08) and subsequent unscheduled repeat catheterization (7.6% vs. 13.3%, p = 0.05) but did not reduce the rate of infarct-related artery reocclusion (6.7% vs. 5.5%, p = 0.64), reinfarction (6.2% vs. 8.0%, p = 0.46) or mortality (4.3% vs. 3.1%) and was associated with a higher incidence of stroke (2.4% vs. 0%, p = 0.03). IABP use did not result in enhanced myocardial recovery as assessed by paired admission to predischarge and 6-week rest and exercise left ventricular ejection fraction. CONCLUSIONS: In contrast to previous studies, a prophylactic IABP strategy after primary PTCA in hemodynamically stable high risk patients with AMI does not decrease the rates of infarct-related artery reocclusion or reinfarction, promote myocardial recovery or improve overall clinical outcome.


Asunto(s)
Angioplastia Coronaria con Balón , Contrapulsador Intraaórtico , Infarto del Miocardio/terapia , Angiografía Coronaria , Hemorragia/etiología , Humanos , Infarto del Miocardio/prevención & control , Estudios Prospectivos , Recurrencia , Resultado del Tratamiento
9.
Med Clin North Am ; 78(5): 1091-122, 1994 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8078371

RESUMEN

We have presented a review of the present literature on new modalities to diagnose nosocomial pneumonia. Procedures are now available that, when correctly used, can establish a diagnosis of pneumonia with a high degree of reliability. In our institution, reliance on bronchoscopic modalities has simplified management of patients with suspected VAP, by eliminating confusion and rationalizing antibiotic treatment. Invasive procedures, however, should be performed only if the results of cultures are consistently applied to treatment. As this field rapidly evolves, we hope that this review will provide the reader with a foundation to understand new developments.


Asunto(s)
Infección Hospitalaria/diagnóstico , Neumonía/diagnóstico , Humanos
10.
J Pers Soc Psychol ; 52(5): 881-9, 1987 May.
Artículo en Inglés | MEDLINE | ID: mdl-3585700

RESUMEN

Self-consistency theory assumes that people want others to treat them in a predictable manner. Self-enhancement theory contends that people want others to treat them in a positive manner. We attempted to help reconcile the two theories by testing the hypothesis that people's cognitive responses conform to self-consistency theory and their affective responses conform to self-enhancement theory. We presented individuals who possessed either positive or negative self-concepts with either favorable or unfavorable social feedback. We then measured cognitive reactions to the feedback (e.g., perceived self-descriptiveness) and affective reactions to the feedback (e.g., mood states). Cognitive responses were primarily driven by the consistency of the feedback and affective responses were controlled by how enhancing it was. We propose that conceptualizing cognition an affect as partially independent mental systems helps resolve some long-standing paradoxes regarding people's responses to self-relevant social feedback.


Asunto(s)
Afecto , Cognición , Relaciones Interpersonales , Autoimagen , Retroalimentación , Femenino , Humanos , Masculino
11.
Talanta ; 30(3): 201-3, 1983 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18963348

RESUMEN

The response characteristics of freshly prepared membranes containing valinomycin are compared to those of membranes of identical composition prepared 2 and 10 years earlier. Independent melting point and infrared spectroscopy data on valinomycin of different ages are presented to substantiate its long-term stability. The separate-solution method was employed to establish selectivity coefficients for Rb(+), Cs(+), Li(+), H(+), Na(+) and NH(4)(+) relative to K(+) for freshly prepared and aged membranes. The maximum values for Na(+) ranged from 10(-4.69) for freshly prepared membranes to 10(-4.27) for 10-year old membranes. The slope of the emf vs. potassium ion activity over the range 10(-4)-10(-1)m was 58.5 mV/decade for freshly prepared membranes and 57.7 mV/decade for aged membranes. The time needed to reach 99% of the final emf was less than 1 min for freshly prepared and 2-year old membranes but 3-6 min for 10-year old membranes. Possible measures to increase the shelf life of these and similar membranes are suggested.

12.
15.
Science ; 206(4418): 563-5, 1979 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-17759426

RESUMEN

Carbon particles extracted from sediments collected by box coring from southeastern Lake Michigan were compared with carbon particles extracted from oil, coal, and wood fly ash. Sediments deposited after 1900 contained coal, oil, and wood carbons; older sediments contained only wood carbon.

17.
20.
Nature ; 233(5320): 474-6, 1971 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-16063452
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