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1.
Science ; 368(6498): 1477-1481, 2020 06 26.
Artículo en Inglés | MEDLINE | ID: mdl-32587019

RESUMEN

The closet exoplanets to the Sun provide opportunities for detailed characterization of planets outside the Solar System. We report the discovery, using radial velocity measurements, of a compact multiplanet system of super-Earth exoplanets orbiting the nearby red dwarf star GJ 887. The two planets have orbital periods of 9.3 and 21.8 days. Assuming an Earth-like albedo, the equilibrium temperature of the 21.8-day planet is ~350 kelvin. The planets are interior to, but close to the inner edge of, the liquid-water habitable zone. We also detect an unconfirmed signal with a period of ~50 days, which could correspond to a third super-Earth in a more temperate orbit. Our observations show that GJ 887 has photometric variability below 500 parts per million, which is unusually quiet for a red dwarf.

2.
Eur J Vasc Endovasc Surg ; 39(1): 23-5, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19906550

RESUMEN

Mycotic carotid pseudoaneurysms are rare and challenging to manage. Traditional surgical approaches are technically demanding and can be associated with a high morbidity and mortality. The use of endovascular stents in infected fields remains controversial, and long-term efficacy has not been fully clarified. We describe a case where a combined staged endovascular and open surgical approach was used to successfully manage a mycotic carotid pseudoaneurysm that developed following dental extraction. A covered endovascular stent was used to temporarily exclude the infected pseudoaneurysm, before proceeding to early definitive surgical management. We suggest that staged endovascular therapy followed by early surgical repair should be considered for this difficult surgical problem.


Asunto(s)
Aneurisma Falso/cirugía , Aneurisma Infectado/cirugía , Implantación de Prótesis Vascular , Enfermedades de las Arterias Carótidas/cirugía , Vena Safena/trasplante , Extracción Dental/efectos adversos , Anciano , Aneurisma Falso/diagnóstico por imagen , Aneurisma Falso/microbiología , Aneurisma Infectado/diagnóstico por imagen , Aneurisma Infectado/microbiología , Antibacterianos/uso terapéutico , Implantación de Prótesis Vascular/instrumentación , Enfermedades de las Arterias Carótidas/diagnóstico por imagen , Enfermedades de las Arterias Carótidas/microbiología , Desbridamiento , Humanos , Masculino , Terapia de Presión Negativa para Heridas , Stents , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
3.
Catheter Cardiovasc Interv ; 71(1): 108-11, 2008 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-18098211

RESUMEN

OBJECTIVE: We report our experience with the elective placement of below-knee, drug-eluting stents in patients with chronic limb ischemia. BACKGROUND: Infrapopliteal percutaneous transluminal angioplasty has been associated with a lower rate of procedural success and high rate of restenosis because of the small size of the tibial vessels and the prevalence of calcified and diffuse atherosclerotic disease. Prior published data reports 3-year patency rates below 25%. Bare metal stents have been reported in bailout situations. Drug-eluting stents have markedly reduced restenosis compared to bare metal stents in the coronary vasculature, but there is little data supporting the use of these devices below the knee. METHODS: Elective placement of drug-eluting stents in infrapopliteal lesions was performed on 10 patients with severe (> or =Fontaine Stage IIb) claudication (n = 1) or limb-threatening ischemia (n = 9) (rest pain, nonhealing ulcers and gangrene). RESULTS: A total of 17 drug-eluting stents were electively placed in 12 below-knee arteries in 10 patients, resulting in an average of 1.7 +/- 0.7 stents per patient. The mean lesion length was 24.8 +/- 10.9 mm, the mean total stent length was 38.3 +/- 19.1 mm, and the mean nominal stent diameter was 2.8 +/- 0.3 mm. One patient required target vessel revascularization (TVR) at 3 weeks because of stent thrombosis. TVR was 10% at 12.4 +/- 6.5 months of follow-up. Clinically driven angiography in three different patients was performed at 4, 15, and 16 months and confirmed drug-eluting stent patency in each case. CONCLUSIONS: The use of below-knee drug-eluting stents is feasible and appears to be safe in our small series of complex infrapopliteal lesions causing chronic limb ischemia. The occurrence of a single case of stent thrombosis warrants continued observation in this cohort. Prospective clinical trials will be necessary to confirm the benefits and justify the costs of this strategy for treating patients with infrapopliteal culprit lesions and chronic limb ischemia.


Asunto(s)
Stents Liberadores de Fármacos , Claudicación Intermitente/terapia , Isquemia/terapia , Pierna/irrigación sanguínea , Anciano , Enfermedad Crónica , Comorbilidad , Constricción Patológica , Femenino , Humanos , Isquemia/epidemiología , Masculino , Persona de Mediana Edad , Recurrencia
6.
Catheter Cardiovasc Interv ; 54(1): 1-5, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11553939

RESUMEN

The safety and efficacy of endoluminal stenting in treating atherosclerotic vertebral artery disease was evaluated in 38 vessels in 32 patients. Indications for revascularization included diplopia (n = 4), blurred vision (n = 4), dizziness (n = 23), transient ischemic attacks (n = 4), drop attack (n = 1), gait disturbance (n = 1), headache (n = 2), and asymptomatic critical stenosis (n = 1). Success (< 20% residual diameter stenosis, without stroke or death) was achieved in all 32 patients (100%). One patient experienced a transient ischemic attack (TIA) 1 hr after the procedure. At follow-up (mean, 10.6 months), all patients (100%) were alive and 31/32 (97%) were asymptomatic. One patient (3%) had in-stent restenosis at 3.5 months and underwent successful balloon angioplasty. Endoluminal stenting of vertebral artery lesions is safe, effective, and durable as evidenced by the low recurrence rate. Primary stent placement is an attractive option for atherosclerotic vertebral artery stenotic lesions. Cathet Cardiovasc Intervent 2001;54:1-5.


Asunto(s)
Angioplastia de Balón , Arteriosclerosis/terapia , Stents , Arteria Vertebral/cirugía , Insuficiencia Vertebrobasilar/terapia , Adulto , Anciano , Anciano de 80 o más Años , Arteriosclerosis/diagnóstico por imagen , Femenino , Humanos , Masculino , Persona de Mediana Edad , Radiografía , Resultado del Tratamiento , Arteria Vertebral/diagnóstico por imagen , Insuficiencia Vertebrobasilar/diagnóstico por imagen
7.
Catheter Cardiovasc Interv ; 53(2): 259-63, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11387617

RESUMEN

Pseudoaneurysm formation of the femoral artery is a well-known complication following catheter-based vascular procedures. Ultrasound-guided compression or surgical correction are commonly used for its repair. We describe a new method of treatment for femoral pseudoaneurysm. The pseudoaneurysm is visualized by contralateral angiography and thrombosed with a percutaneous thrombin injection while the distal vessel is isolated with a brief balloon inflation. Fluoroscopically guided percutaneous thrombin injection is a promising, minimally invasive technique for the treatment of iatrogenic pseudoaneurysm, especially in patients with compromised distal circulation.


Asunto(s)
Aneurisma Falso/tratamiento farmacológico , Arteria Femoral , Hemostáticos/uso terapéutico , Trombina/uso terapéutico , Adolescente , Anciano , Anciano de 80 o más Años , Humanos , Inyecciones/métodos , Masculino , Persona de Mediana Edad
8.
Catheter Cardiovasc Interv ; 52(4): 457-67, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11285598

RESUMEN

Percutaneous techniques have dramatically changed our approach to coronary and peripheral revascularization. Intracranial atherosclerosis is a highly morbid disease; however, techniques for revascularization are still in evolution. The authors comprise a multidisciplinary team of neurologists, neuroradiologists, and interventional cardiologists who have collaborated in treating fifteen patients with symptomatic intracranial stenosis who have failed medical therapy. The acute success rate (100%) and one-year freedom from death and stroke (93.4%) using balloon angioplasty and provisional stenting are encouraging. A surprising observation in this patient cohort was that 53% of patients had improvement or resolution of a deficit that was chronic and presumed to be permanent and irreversible. This type of chronic but reversible deficit is termed "brain angina". The background, rationale for a multidisciplinary team, techniques, and preliminary results of intracranial angioplasty with provisional stenting are presented.


Asunto(s)
Estenosis Carotídea/terapia , Arteriosclerosis Intracraneal/terapia , Stents , Anciano , Anciano de 80 o más Años , Angioplastia de Balón , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Resultado del Tratamiento
11.
J Endovasc Ther ; 8(1): 75-82, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11220474

RESUMEN

PURPOSE: To assess the procedural and long-term clinical outcomes of balloon angioplasty of the profunda femoris artery in patients with severe limb ischemia. METHODS: Thirty-one consecutive patients were evaluated for severe ischemia in 32 limbs: 13 (41%) were categorized Fontaine class 2B, and 19 (59%) were class 3 or 4. The superficial femoral artery was occluded in 20 (62%) limbs; an additional vessel was treated in 22 (69%) limbs. RESULTS: Procedural success was achieved in 91% (31/32) of limbs. The ankle-brachial index increased from 0.5 +/- 0.2 at baseline to 0.7 +/- 0.2 after intervention (p < 0.01). In-hospital limb salvage was 94% (30/32), and in-hospital event-free survival was 90% (28/31). At a mean follow-up of 34 +/- 20 months, no additional amputations were necessary; 3 patients required repeat revascularization, and 5 patients died. Freedom from revascularization was 88% in the 25 survivors. At follow-up, 88% of the patients had Fontaine class 1 or 2A symptoms, and only 12% had Fontaine class 2B or higher (p < 0.001 compared with baseline). CONCLUSIONS: These data suggest that percutaneous profundaplasty is safe, effective, and may be considered as an alternative to surgical therapy in patients with anatomically suitable lesions.


Asunto(s)
Angioplastia Coronaria con Balón , Isquemia/terapia , Pierna/irrigación sanguínea , Anciano , Anciano de 80 o más Años , Angiografía , Femenino , Arteria Femoral/diagnóstico por imagen , Estudios de Seguimiento , Humanos , Isquemia/diagnóstico por imagen , Isquemia/cirugía , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias , Retratamiento , Análisis de Supervivencia
12.
Catheter Cardiovasc Interv ; 52(1): 56-8, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11146524

RESUMEN

An increase in QT dispersion (QTd) is associated with myocardial ischemia and may serve as a marker of ischemia and ventricular arrhythmia. We studied the effect of early reperfusion with rheolytic thrombectomy using an angiojet catheter (Possis, Minneapolis, MN) on QTd in 12 patients who presented with acute myocardial infarction. QTd and QT dispersion, rate-corrected for RR interval, were significantly reduced from 57 +/- 16 and 68 +/- 13 msec before reperfusion to 34 +/- 16 and 44 +/- 19 msec after reperfusion respectively (mean +/- SD; P < 0.002 and P < 0.0008, respectively). Successful reperfusion with rheolytic thrombectomy reduces QTd and may confer electrical stability to vulnerable myocardium. Reduction in indexes of repolarization inhomogeneity with reperfusion may serve as a noninvasive marker of coronary patency.


Asunto(s)
Angioplastia Coronaria con Balón/métodos , Electrocardiografía , Infarto del Miocardio/diagnóstico , Infarto del Miocardio/terapia , Trombectomía/métodos , Anciano , Cateterismo Cardíaco , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Reperfusión Miocárdica/métodos , Estudios Retrospectivos , Sensibilidad y Especificidad , Resultado del Tratamiento
13.
Ochsner J ; 3(2): 70-7, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21765722

RESUMEN

Percutaneous endovascular intervention has revolutionized the treatment of peripheral vascular disease by allowing successful treatment of patients who are not good surgical candidates. Cardiologists with peripheral vascular training are more readily able to identify patients with concomitant peripheral arterial disease. It has been our experience that the technical skills necessary to perform coronary angioplasty are transferable to the peripheral vasculature. However, an understanding of the natural history of peripheral disease and of patient and lesion selection criteria, and the knowledge of other treatment alternatives are essential elements required to perform these procedures safely and effectively. There are inherent advantages for patients when the interventionalist performing the procedure is also the clinician responsible for the pre- and post-procedure care, analogous to the vascular surgeon who cares for patients before and after surgical procedures. In view of the increased incidence of coronary artery disease in patients with atherosclerotic peripheral vascular disease, the participation of a cardiologist in their care seems appropriate.

14.
J Pediatr Endocrinol Metab ; 13 Suppl 6: 1503-8, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11202227

RESUMEN

Under the influence of testicular secretion, the male vocal cords increase in length by 67% in adult men compared with prepubertal boys, whereas in the female the increase is only 24%. This greater length and an increase in vocal cord mass is responsible for the lowering of pitch of the male voice during puberty. From the late 16th century, castration was carried out in Italy to preserve the unbroken male voice into adult life, but the high pitch was accompanied by fully grown resonating chambers and a large thoracic capacity, giving rise to the unique voice of the castrato. The initial stimulus for the production of castrati came from the Sistine Chapel in Rome, to provide singers for the complex church music of the time. The second reason was the coming of opera to Italy at the beginning of the 17th century. Boys were castrated between the ages of 7 and 9 years, and underwent a long period of voice training. A small number became international opera stars, of whom the most famous was Farinelli, whose voice ranged over three octaves. By the end of the 18th century, fashions in opera had changed so that the castrati declined except in the Vatican, where the Sistine Chapel continued to employ castrati until 1903. The last of the castrati was Alessandro Moreschi, who died in 1924 and made gramophone recordings that provide the only direct evidence of a castrato's singing voice.


Asunto(s)
Eunuquismo/historia , Música/historia , Orquiectomía , Voz , Constitución Corporal , Catolicismo/historia , Eunuquismo/fisiopatología , Historia del Siglo XVI , Historia del Siglo XVII , Historia del Siglo XVIII , Historia del Siglo XIX , Historia del Siglo XX , Humanos , Italia , Masculino , Pubertad
15.
Catheter Cardiovasc Interv ; 47(4): 415-22, 1999 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10470470

RESUMEN

The aim of the study was to determine if a hypercoagulable state that may persist for several months after an acute myocardial infarction may contribute to an increased incidence of stent thrombosis. Primary stenting was performed in 104 consecutive patients with acute myocardial infarction using 147 coronary stents. Twenty-eight patients (27%) were diabetic and 55 patients (53%) were smokers. A single stent was placed in 63%, two stents in 33%, and more than two stents in 4% of the patients. Procedural success was obtained in 97% of the patients. All stents were deployed using high-pressure balloon inflation. The reference vessel diameter and minimal lumen diameter after stent deployment were 3.30 +/- 0.42 and 3.23 +/- 0.42 mm, respectively. Six patients (5.7%) developed stent thrombosis within 1 month after the procedure complicated by reinfarction in five of the six patients. At 1-month follow-up, all patients remained alive. On multivariate analysis, independent predictors of stent thrombosis were diabetes mellitus (relative risk [RR] 5.2; 95% confidence interval [CI] 1.8, 25.1), tobacco use (RR 4.5; 95% CI 1.3, 24.5), number of stents: 1 vs. > 1 (RR 3.7; 95% CI 1.1, 15.9), minimal lumen diameter poststent placement (RR 0.03; 95% CI 0.0002, 0.74), and duration of chest pain before intervention (RR 1.1; 95% CI 1.01, 1.25). Stent thrombosis had not been associated with diabetes mellitus and tobacco use previously but is in agreement with the enhanced platelet aggregability, coagulation factor abnormalities, and impaired fibrinolysis characteristic of these patients.


Asunto(s)
Vasos Coronarios , Infarto del Miocardio/terapia , Stents/efectos adversos , Trombosis/etiología , Vasos Coronarios/patología , Complicaciones de la Diabetes , Femenino , Humanos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Infarto del Miocardio/complicaciones , Infarto del Miocardio/patología , Factores de Riesgo , Fumar/efectos adversos
16.
Am Heart J ; 138(3 Pt 1): 446-55, 1999 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10467194

RESUMEN

BACKGROUND: The outcome of patients with diabetes after myocardial infarction (MI) has traditionally been worse than in their nondiabetic counterparts before and during the thrombolytic therapy era. Whether the fate of patients with diabetes might improve with mechanical intervention, particularly with primary stenting, has not previously been studied. METHODS: We compared the angiographic and clinical outcome of 76 nondiabetic patients (aged 61 +/- 14 years; 66% male) and 28 patients with diabetes (aged 65 +/- 12 years; 64% male) consecutively treated with primary stenting for acute MI. Coronary Thrombolysis In Myocardial Infarction grade 3 flow was restored in 96% of diabetic and 97% of nondiabetic patients. RESULTS: Angiographic results after stent deployment were similar in the 2 groups. At 1-month follow-up, all patients in both groups were alive. Patients with diabetes had a much higher incidence of stent thrombosis (18% vs 1%; P =.003), which accounted for the majority of the major cardiac events at 1 month (21% vs 4%; P =.009). At a mean follow-up of 315 +/- 13 days, 99% of nondiabetic and 89% of patients with diabetes were alive (P =.04). Overall freedom from a major cardiac event (death, MI, target vessel revascularization) at 315 +/- 13 day follow-up was 88% for nondiabetics and 54% for patients with diabetes (P =.0003). By multivariate analysis, diabetes mellitus was the most important predictor for development of 1-month (RR 9.89; 95% confidence interval, 1.6-30) and late major cardiovascular events (RR 8.39; 95% confidence interval, 2.93-24). CONCLUSIONS: Primary stenting in acute MI is highly effective in restoring immediate TIMI 3 coronary flow in nondiabetic patients and patients with diabetes. This procedure may improve benefit in terms of mortality rate to both groups, particularly in patients with diabetes, compared with previous reports with thrombolytic therapy. Nevertheless, stent thrombosis and major cardiovascular events at 1 month and late follow-up are more frequent in patients with diabetes.


Asunto(s)
Angioplastia Coronaria con Balón/instrumentación , Angiografía Coronaria , Complicaciones de la Diabetes , Infarto del Miocardio/cirugía , Stents , Anciano , Enfermedad Coronaria/diagnóstico por imagen , Enfermedad Coronaria/patología , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Análisis de Supervivencia , Resultado del Tratamiento
19.
Cathet Cardiovasc Diagn ; 45(4): 386-93, 1998 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9863742

RESUMEN

We tested the efficacy of rheolytic thrombectomy in treating 21 patients (mean age 68+/-12 years; 66% male) and 22 vessels (limbs) who presented to the hospital within 2 weeks of the development of limb-threatening ischemia. Fifty-two percent had contraindications to use thrombolytics, and 57% had severe comorbidities. All of the vessels were occluded with thrombus on the initial angiogram. Procedural success was achieved in 20 limbs (91%). Three patients expired in the hospital, and one expired at follow-up due to nonvascular causes. Acute limb salvage was achieved in 18 of 19 limbs (95%) in the 18 survivors, and 6-month limb salvage was achieved in 16 of 18 limbs (89%) in the 17 survivors. Rheolytic thrombectomy is effective in restoring immediate blood flow in acute limb-threatening ischemia, especially in high-risk surgical patients or patients with contraindications to thrombolytic therapy.


Asunto(s)
Cateterismo/instrumentación , Extremidades/irrigación sanguínea , Isquemia/cirugía , Trombectomía/instrumentación , Trombosis/cirugía , Anciano , Comorbilidad , Diseño de Equipo , Femenino , Estudios de Seguimiento , Oclusión de Injerto Vascular/cirugía , Humanos , Isquemia/epidemiología , Masculino , Persona de Mediana Edad , Reología , Trombectomía/métodos , Resultado del Tratamiento
20.
Cathet Cardiovasc Diagn ; 45(4): 428-33, 1998 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9863754

RESUMEN

We describe a case of essential thrombocythemia in a 34-year-old male who presented with acute anterior wall myocardial infarction and a platelet count of 2,100,000/mm3. Primary percutaneous coronary angioplasty and stenting were performed. Postangioplasty course was complicated by stent thrombosis requiring repeat coronary angioplasty and persistent femoral arterial bleeding that was treated with surgical exploration and repair. The patient was subsequently treated with platelet pheresis, acetylsalicylic acid, ticlopidine, hydroxyurea, and anagrelide without further complications.


Asunto(s)
Angioplastia Coronaria con Balón , Trombosis Coronaria/etiología , Oclusión de Injerto Vascular/etiología , Infarto del Miocardio/complicaciones , Infarto del Miocardio/terapia , Stents , Trombocitemia Esencial/complicaciones , Adulto , Angiografía Coronaria , Trombosis Coronaria/diagnóstico por imagen , Arteria Femoral , Oclusión de Injerto Vascular/diagnóstico por imagen , Hemostasis Quirúrgica , Humanos , Masculino , Recurrencia
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