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1.
Neural Plast ; 2016: 5961362, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26881118

RESUMEN

OBJECTIVES: The primary objective of this study was to investigate the effects of five consecutive, daily 20-minute sessions of M1 a-tDCS on motor learning in healthy, cognitively intact, aging adults. DESIGN: A total of 23 participants (51 to 69 years old) performed five consecutive, daily 20-minute sessions of a serial reaction time task (SRT task) concomitant with either anodal (n = 12) or sham (n = 11) M1 a-tDCS. RESULTS: We found a significant group × training sessions interaction, indicating that whereas aging adults in the sham group exhibited little-to-no sequence-specific learning improvements beyond the first day of training, reproducible improvements in the ability to learn new motor sequences over 5 consecutive sessions were the net result in age-equivalent participants from the M1 a-tDCS group. A significant main effect of group on sequence-specific learning revealed greater motor learning for the M1 a-tDCS group when the five learning sessions were averaged. CONCLUSION: These findings raise into prominence the utility of multisession anodal TDCS protocols in combination with motor training to help prevent/alleviate age-associated motor function decline.


Asunto(s)
Envejecimiento , Aprendizaje/fisiología , Corteza Motora/fisiología , Desempeño Psicomotor/fisiología , Estimulación Transcraneal de Corriente Directa/métodos , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Actividad Motora , Tiempo de Reacción
2.
Sci Rep ; 8(1): 12092, 2018 08 14.
Artículo en Inglés | MEDLINE | ID: mdl-30108244

RESUMEN

This study examines the benefit of using Ocean Mean Temperature (OMT) to aid in the prediction of the sign of Indian Summer Monsoon Rainfall (ISMR) anomalies. This is a statistical examination, rather than a process study. The thermal energy needed for maintaining and intensifying hurricanes and monsoons comes from the upper ocean, not just from the thin layer represented by sea surface temperature (SST) alone. Here, we show that the southwestern Indian OMT down to the depth of the 26 °C isotherm during January-March is a better qualitative predictor of the ISMR than SST. The success rate in predicting above- or below-average ISMR is 80% for OMT compared to 60% for SST. Other January-March mean climate indices (e.g., NINO3.4, Indian Ocean Dipole Mode Index, El Niño Southern Oscillation Modoki Index) have less predictability (52%, 48%, and 56%, respectively) than OMT percentage deviation (PD) (80%). Thus, OMT PD in the southwestern Indian Ocean provides a better qualitative prediction of ISMR by the end of March and indicates whether the ISMR will be above or below the climatological mean value.

3.
Phytopathology ; 97(5): 603-10, 2007 May.
Artículo en Inglés | MEDLINE | ID: mdl-18943580

RESUMEN

ABSTRACT Poplar leaf rust caused by Melampsora medusae f. sp. deltoidae is a widespread disease in North America, where epidemics occur within zones of sympatry and allopatry of telial hosts (Populus spp.) and aecial hosts (Larix spp.). To test the hypothesis that epidemics originate in the zone of sympatry where the rust can complete its life cycle, populations in sympatry and allopatry were analyzed with single-strand conformational polymorphism for codominant detection of alleles directly from uredinia. More alleles were detected in rust populations in the zone of host sympatry than in allopatry. Almost all alleles found in the zone of allopatry were a subset of the allelic diversity present in the zone of host sympatry. Distance analyses clustered populations according to geographic origin, but not sampling year or type of stand (plantation or natural stands). Large differences in allelic and genotypic frequency were observed between years in allopatry but not in sympatry, suggesting new colonizations in allopatric populations. Our results point to a dynamic and complex pattern of inoculum dissemination in polar leaf rust. The hypothesis most consistent with our results is that populations in sympatry represent a source of inoculum for epidemics, with some annual recolonization in allopatry, possibly via intermediate population jumps.

4.
Cancer Res ; 38(6): 1568-71, 1978 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-206351

RESUMEN

Raised levels of what appeared to be beta-lipotropin (beta-LPH), beta-melanotropic hormone, and beta-endorphin were detected by radioimmunoassay in the plasma of rats bearing the mammotropic transplantable pituitary tumor MtT-F4. The immunoreactivity to anti-beta-endorphin in the assay was displayed by a substance with the molecular weight of beta-LPH, as determined by gel filtration. Isolated cells of MtT-F4 tumor incubated in vitro released immunoreactive beta-LPH and beta-endorphin, with the expected molecular weights, into the incubation medium. These results suggest that the pituitary transplantable rat tumor MtT-F4 secretes peptides structurally related to beta-LPH.


Asunto(s)
Endorfinas/metabolismo , Neoplasias Hipofisarias/metabolismo , Hormona Adrenocorticotrópica/metabolismo , Animales , Fenómenos Químicos , Química , Endorfinas/inmunología , Masculino , Hormonas Estimuladoras de los Melanocitos/metabolismo , Trasplante de Neoplasias , Neoplasias Experimentales/metabolismo , Prolactina/metabolismo , Radioinmunoensayo , Ratas , Ratas Endogámicas F344 , Trasplante Isogénico , beta-Lipotropina/metabolismo
5.
Circulation ; 101(16): 1919-24, 2000 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-10779457

RESUMEN

BACKGROUND: We previously reported that depression after myocardial infarction (MI) increases the long-term risk of cardiac mortality. Other research suggests that social support may also influence prognosis. This article examines the interrelationships between baseline depression and social support in terms of cardiac prognosis and changes in depression symptoms over the first post-MI year. METHODS AND RESULTS: For this study, 887 patients completed the Beck Depression Inventory (BDI) and the Perceived Social Support Scale (PSSS) at about 7 days after MI. Some 32% had BDIs > or =10, indicating mild to moderate depression. One-year survival status was determined for all patients. Follow-up interviews, including the BDI, were conducted with 89% of survivors. There were 39 deaths (35 cardiac). Elevated BDI scores were related to cardiac mortality (P=0.0006), but PSSS scores and other measures of social support were not. There was a significant interaction between depression and the PSSS (P=0. 016). The relationship between depression and cardiac mortality decreased with increasing support. Furthermore, residual change score analysis revealed that among 1-year survivors who had been depressed at baseline, higher baseline social support was related to more improvement in depression symptoms than expected. CONCLUSIONS: Post-MI depression is a predictor of 1-year cardiac mortality, but social support is not directly related to survival. However, very high levels of support appear to buffer the impact of depression on mortality. Furthermore, high levels of support predict improvements in depression symptoms over the first post-MI year in depressed patients. High levels of support may protect patients from the negative prognostic consequences of depression because of improvements in depression symptoms.


Asunto(s)
Depresión/epidemiología , Depresión/psicología , Infarto del Miocardio/mortalidad , Infarto del Miocardio/psicología , Apoyo Social , Adulto , Anciano , Anciano de 80 o más Años , Depresión/diagnóstico , Femenino , Humanos , Modelos Lineales , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Pronóstico , Pruebas Psicológicas
6.
Circulation ; 104(5): 522-6, 2001 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-11479247

RESUMEN

BACKGROUND: In trials of patients with left ventricular dysfunction or heart failure, ACE inhibitor use was unexpectedly associated with reduced myocardial infarction (MI). Using the Heart Outcomes Prevention Evaluation (HOPE) trial data, we tested prospectively whether ramipril, an ACE inhibitor, could reduce coronary events and revascularization procedures among patients with normal left ventricular function. METHODS AND RESULTS: In the HOPE trial, 9297 high-risk men and women, >/=55 years of age with previous cardiovascular disease or diabetes plus 1 risk factor, were randomly assigned to ramipril (up to 10 mg/d), vitamin E (400 IU/d), their combination, or matching placebos. During the mean follow-up of 4.5 years, there were 482 (10.4%) patients with clinical MI and unexpected cardiovascular death in the ramipril group compared with 604 (12.9%) in the placebo group [relative risk reduction (RRR), 21% (95% CI) (11,30); P<0.0003]. Ramipril was associated with a trend toward less fatal MI and unexpected death [4.0% versus 4.7%; RRR, 16% (-3, 31)] and with a significant reduction in nonfatal MI [5.6% versus 7.2%; RRR, 23% (9,34)]. Risk reductions in MI were documented in participants taking or not taking beta-blockers, lipid lowering, and/or antiplatelet agents. Although ramipril had no impact on hospitalizations for unstable angina [11.9% versus 12.2%; RRR, 3% (-9,14)], it reduced the risk of worsening and new angina [27.2% versus 30.0%; RRR, 12% (5,18); P<0.0014] and coronary revascularizations [12.5% versus 14.8%; RRR, 18%; (8,26) P<0.0005]. CONCLUSIONS: In this high-risk cohort, ramipril reduced the risk of MI, worsening and new angina, and the occurrence of coronary revascularizations.


Asunto(s)
Inhibidores de la Enzima Convertidora de Angiotensina/uso terapéutico , Infarto del Miocardio/prevención & control , Ramipril/uso terapéutico , Anciano , Angina Inestable/prevención & control , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Isquemia Miocárdica/prevención & control , Revascularización Miocárdica/estadística & datos numéricos , Factores de Riesgo , Análisis de Supervivencia
7.
Circulation ; 100(9): 910-7, 1999 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-10468520

RESUMEN

BACKGROUND: In PTCA patients with multivessel coronary artery disease, incomplete revascularization (IR) is the result of both pre-PTCA strategy and initial lesion outcome. The unique contribution of these components on long-term patient outcome is uncertain. METHODS AND RESULTS: From the Bypass Angioplasty Revascularization Investigation (BARI), 2047 patients who underwent first-time PTCA were evaluated. Before enrollment, all significant lesions were assessed by the PTCA operator for clinical importance and intention to dilate. Complete revascularization (CR) was defined as successful dilatation of all clinically relevant lesions. Planned CR was indicated in 65% of all patients. More lesions were intended for PTCA in these patients compared with those with planned IR (2.8 versus 2.1). Successful dilatation of all intended lesions occurred in 45% of patients with planned CR versus 56% with planned IR (P<0. 001). In multivariable analysis, planned IR (versus planned CR), initial lesions attempted (not all versus all intended lesions attempted), and initial lesion outcome (not all versus all attempted lesions successful) were unrelated to 5-year risk of cardiac death or death/myocardial infarction but were all independently related to risk of CABG. CONCLUSIONS: Overall, a pre-PTCA strategy of IR in BARI-like patients appears comparable to a strategy of CR except for a higher need for CABG. Whether the use of new devices may attenuate the elevated risk of CABG in patients with multivessel disease and planned IR remains to be determined.


Asunto(s)
Angioplastia Coronaria con Balón , Enfermedad Coronaria/patología , Enfermedad Coronaria/terapia , Anciano , Factores de Confusión Epidemiológicos , Supervivencia sin Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Índice de Severidad de la Enfermedad , Resultado del Tratamiento
8.
Circulation ; 102(24): 2945-51, 2000 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-11113044

RESUMEN

BACKGROUND: Although refinements have occurred in coronary angioplasty over the past decade, little is known about whether these changes have affected outcomes. METHODS AND RESULTS: Baseline features and in-hospital and 1-year outcomes of 1559 consecutive patients in the 1997-1998 Dynamic Registry who were having first coronary intervention were compared with 2431 patients in the 1985-1986 National Heart, Lung, and Blood Institute Registry. Compared with patients in the 1985-1986 Registry, Dynamic Registry patients were older (mean age, 62 versus 58 years; P:<0.001) and more often female (32.1% versus 25.5%; P:<0.001). In the Dynamic Registry, procedures were more often performed for acute myocardial infarction (22.9% versus 9.9%; P:<0.001) and treated lesions were more severe (84.5% versus 82.5% diameter reduction; P:<0.001), thrombotic (22.1% versus 11.3%; P:<0.001) or calcified (29.5% versus 10.8%; P:<0.001). Stents were used in 70.5% of Dynamic Registry patients, whereas 1985-1986 patients received balloon angioplasty alone. Procedural success was higher in the Dynamic Registry (92.0% versus 81.8%; P:<0.001) and the rate of in-hospital death, myocardial infarction, and emergency coronary bypass surgery combined was lower (4.9% versus 7.9%; P:=0.001) than in the 1985-1986 Registry. The 1-year rate for CABG was lower in the Dynamic Registry (6.9% versus 12.6%; P:<0.001). CONCLUSIONS: Although Dynamic Registry patients had more unstable and complex coronary disease than those in the 1985-1986 Registry, their rate of procedural success was higher whereas rates of complications and subsequent CABG were lower. Results of percutaneous coronary intervention have improved substantially over the past decade.


Asunto(s)
Angioplastia Coronaria con Balón , Enfermedad Coronaria/terapia , Enfermedad Coronaria/etnología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Multicéntricos como Asunto , Sistema de Registros , Resultado del Tratamiento
9.
J Am Coll Cardiol ; 36(2): 355-65, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10933343

RESUMEN

OBJECTIVES: The aim of this review is to discuss the particularities of coronary artery disease (CAD), the effect of intensive medical management and the outcome of percutaneous and surgical revascularization in patients with diabetes mellitus (DM). BACKGROUND: CAD represents the leading cause of death in patients with DM. Numerous clinical, biological and angiographic risk factors have been shown to be associated with CAD in diabetic patients. METHODS: Metabolic abnormalities in patients with DM including insulin resistance, hyperglycemia and dyslipidemia are briefly discussed. Then the potential roles of medical management and of percutaneous and surgical coronary revascularization are more extensively reviewed. RESULTS: More vigorous control of hyperglycemia, hyperlipidemia, hypertension and other risk factors may be of crucial importance for risk reduction. Despite remarkable progress in recent years, the choice of a coronary revascularization strategy remains a challenge in these patients. Diabetic patients with CAD are predisposed to higher cardiovascular events after balloon angioplasty. Whether stenting and new antiplatelet drugs improve the results of percutaneous revascularization in this population needs further evaluation. The superiority of the surgical approach is also not definitely established. Therefore, many aspects of coronary revascularization are still unclear in these patients. CONCLUSIONS: The results of ongoing randomized trials comparing multiple coronary stents to bypass surgery will likely provide some answers to our questions and additional randomized trials evaluating intensive diabetic control with or without coronary revascularization are needed to determine the best therapeutic approach in these patients.


Asunto(s)
Angiopatías Diabéticas/terapia , Abciximab , Angioplastia Coronaria con Balón , Inhibidores de la Enzima Convertidora de Angiotensina/uso terapéutico , Anticuerpos Monoclonales/uso terapéutico , Anticoagulantes/uso terapéutico , Angiopatías Diabéticas/tratamiento farmacológico , Angiopatías Diabéticas/metabolismo , Angiopatías Diabéticas/fisiopatología , Endotelio Vascular/fisiopatología , Humanos , Hiperglucemia/fisiopatología , Hiperlipidemias/fisiopatología , Fragmentos Fab de Inmunoglobulinas/uso terapéutico , Resistencia a la Insulina , Inhibidores de Agregación Plaquetaria/uso terapéutico , Complejo GPIIb-IIIa de Glicoproteína Plaquetaria/antagonistas & inhibidores , Recurrencia , Factores de Riesgo , Terapia Trombolítica , Resultado del Tratamiento
10.
J Am Coll Cardiol ; 11(5): 908-16, 1988 May.
Artículo en Inglés | MEDLINE | ID: mdl-3128587

RESUMEN

To assess the 3 year risk of anterior myocardial infarction in patients with left anterior descending coronary artery territory disease (30 to 100% stenosis), National Heart, Lung, and Blood Institute (NHLBI) Coronary Artery Surgery Study (CASS) registry patients were identified who were 1) medically treated, and 2) had evidence of viable anterior myocardium at the time of baseline angiography. Prospectively, 118 patients having an anterior infarction within 3 years of baseline angiography were identified from annual follow-up of 4,535 medically treated patients who had left anterior descending coronary artery disease and viable anterior myocardium. From the large residual pool of patients without infarction, 141 were randomly selected from a stratified matrix to represent the entire group. The maximal percent stenosis was estimated by the CASS multiple angiographers, by a current single observer rereading and by contemporary computer measurement techniques. Absolute lumen dimension was assessed by computer measurement. The 3 year risk of anterior infarction was 2% for patients with their most severe left anterior descending stenosis less than 50%, 6% for patients with one such stenosis greater than or equal to 50% and 11% for patients with two or more such stenoses greater than or equal to 50% (p less than 0.02). Stenoses of 90 to 98% had the highest (15%) 3 year risk of anterior myocardial infarction. The three methods used to measure maximal percent stenosis differed little with regard to their predictiveness. Absolute lumen dimension was less predictive of risk. These results may provide a more rational basis on which to base coronary revascularization decisions.


Asunto(s)
Angiografía Coronaria , Enfermedad Coronaria/complicaciones , Grupos Diagnósticos Relacionados , Infarto del Miocardio/etiología , Riesgo , Índice de Severidad de la Enfermedad , Ensayos Clínicos como Asunto , Enfermedad Coronaria/diagnóstico por imagen , Femenino , Estudios de Seguimiento , Humanos , Masculino , Infarto del Miocardio/diagnóstico , Infarto del Miocardio/diagnóstico por imagen , Pronóstico , Estudios Prospectivos , Intensificación de Imagen Radiográfica , Interpretación de Imagen Radiográfica Asistida por Computador , Distribución Aleatoria , Sistema de Registros , Análisis de Regresión , Factores de Tiempo
11.
J Am Coll Cardiol ; 18(2): 368-76, 1991 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-1856404

RESUMEN

In a recent prospective double-blind placebo-controlled trial, a combination of aspirin and dipyridamole was not associated with a reduction in the rate of restenosis within the 1st 6 months after coronary angioplasty. The purpose of this study was to determine whether clinical, anatomic or procedural factors were predictive of the observed restenosis rates in that prospective trial. A total of 247 patients and 280 segments underwent follow-up angiography and quantitative coronary angiographic analysis between 4 and 7 months after coronary angioplasty. Two baseline clinical characteristics--angina class and duration of angina in months--were related to the rate of restenosis by univariate analysis. Patient-related stepwise logistic regression analysis identified severity of angina as the only clinical predictor of restenosis. Three univariate baseline anatomic characteristics--percent diameter stenosis before angioplasty, stenosis greater than 10 mm in length and calcific stenosis--and two early postangioplasty characteristics--residual percent diameter stenosis and residual mean pressure gradient--were predictive of restenosis. Of these, only two--length of stenosis and residual percent diameter stenosis--were independently related to restenosis by multivariate analysis and only the former is identifiable before the procedure. It is concluded that in prospective studies in contrast to retrospective studies, few clinical and anatomic factors appear to be predictive of restenosis after coronary angioplasty.


Asunto(s)
Angioplastia Coronaria con Balón , Aspirina/uso terapéutico , Enfermedad Coronaria/terapia , Dipiridamol/uso terapéutico , Enfermedad Coronaria/epidemiología , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Estudios Prospectivos , Recurrencia , Factores de Riesgo
12.
J Am Coll Cardiol ; 8(1): 32-9, 1986 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-3711529

RESUMEN

The long-term reproducibility and significance of inducible ventricular arrhythmias were assessed in 21 survivors of a myocardial infarction. Programmed ventricular stimulation performed a mean of 12 +/- 2 days (range 8 to 18) after infarction provoked ventricular fibrillation in 2 patients, sustained monomorphic ventricular tachycardia in 8 and nonsustained ventricular tachycardia in 11. Patients were restudied using the same protocol a mean of 8 +/- 2 months (range 4 to 11) after infarction. All patients underwent programmed ventricular stimulation studies in the absence of antiarrhythmic drug treatment. Ventricular tachyarrhythmias could be reinitiated in 16 patients (76%): ventricular fibrillation in 2, sustained ventricular tachycardia in 5 (monomorphic in 4) and nonsustained ventricular tachycardia in 9. A preponderance of inferior infarction was observed among patients with reinducible tachycardias (9 of 16 patients versus 0 of 5 with noninducible tachycardias) (p less than 0.05). No significant difference existed between patients with and without reinducible arrhythmias with respect to severity of coronary artery disease, degree of left ventricular dysfunction, occurrence of ventricular fibrillation in the acute phase of infarction and ventricular arrhythmias detected by 24 hour ambulatory electrocardiographic (Holter) monitoring. There was no significant difference between patients with and without a positive late study in stimulation thresholds, ventricular refractory periods, time interval between initial and repeat testing and use of beta-adrenergic blocking agents. During a mean follow-up period of 17 months (range 10 to 23) one patient with inducible sustained monomorphic ventricular tachycardia at both studies died suddenly. The remaining patients have survived follow-up without experiencing an arrhythmic event.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Arritmias Cardíacas/etiología , Infarto del Miocardio/complicaciones , Adulto , Arritmias Cardíacas/fisiopatología , Estimulación Cardíaca Artificial , Muerte Súbita/etiología , Electrocardiografía , Femenino , Estudios de Seguimiento , Ventrículos Cardíacos/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Prospectivos , Factores de Tiempo
13.
J Am Coll Cardiol ; 9(3): 509-14, 1987 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-2950154

RESUMEN

Plasma immunoreactive atrial natriuretic factor was measured in 10 patients with chronic atrial fibrillation before and after cardioversion to sinus rhythm, and in 14 patients during electrophysiologic evaluation of paroxysmal supraventricular tachycardia. The mean plasma concentration of atrial natriuretic factor in atrial fibrillation was 138 +/- 48 pg/ml and decreased to 116 +/- 45 pg/ml 1 hour after cardioversion to sinus rhythm (p less than 0.005). The mean plasma concentration of atrial natriuretic factor increased from 117 +/- 53 pg/ml in sinus rhythm to 251 +/- 137 pg/ml during laboratory-induced supraventricular tachycardia (p less than 0.005). Right atrial pressures were recorded in 12 patients; the baseline atrial pressure was 4.3 +/- 1.9 mm Hg and increased to 7.4 +/- 3.6 mm Hg during supraventricular tachycardia (p less than 0.005). A modest but significant linear relation was noted between the changes in plasma atrial natriuretic factor and right atrial pressure measurements during induced supraventricular tachycardia (r = 0.60, p less than 0.05). In conclusion, changes in atrial rhythm and pressure may be an important factor modulating the release of atrial natriuretic factor in the circulation and raised levels of this hormone may be a contributing factor for the polyuria and the hypotension associated with paroxysmal supraventricular tachyarrhythmias.


Asunto(s)
Fibrilación Atrial/sangre , Factor Natriurético Atrial/sangre , Taquicardia/sangre , Anciano , Fibrilación Atrial/terapia , Cardioversión Eléctrica , Electrofisiología , Femenino , Frecuencia Cardíaca , Humanos , Masculino , Persona de Mediana Edad , Taquicardia/fisiopatología
14.
J Am Coll Cardiol ; 6(6): 1239-44, 1985 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-2933441

RESUMEN

Percutaneous transluminal coronary angioplasty is an accepted treatment for selected patients with single vessel disease but has not been rigorously evaluated in patients with double vessel disease. Among 769 patients undergoing transluminal coronary angioplasty between 1980 and 1984, 74 with double vessel stenosis of 50% or more underwent double vessel coronary angioplasty. Primary success was obtained for both lesions in 63 patients (85%), for one lesion in 11 patients (15%) and for 137 (93%) of 148 segments overall. Except for myocardial infarction in one patient, no serious complication occurred. Before coronary angioplasty, 15 patients had unstable angina, 14 had Canadian Cardiovascular Society class III and 32 class I to II effort angina and only 2 were asymptomatic. Six months after coronary angioplasty, 27 were asymptomatic, 27 had class I to II and 5 had class III effort angina and 2 had sustained an episode of unstable angina. During the follow-up study, two patients had an infarction and one had coronary artery bypass surgery. Coronary arteriography was performed at a mean of 5.5 +/- 2.1 months after coronary angioplasty in all but three patients. Restenosis was found in 30 (23%) of 132 segments with angiographic control. Restenosis was present in one vessel in 17 patients and in both vessels in 4; 40 patients (66%) had no restenosis. Of the 34 patients with definite or probable angina, 50% had restenosis and 19% of patients with restenosis were symptom free.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Angioplastia de Balón , Enfermedad Coronaria/terapia , Adulto , Angina de Pecho/terapia , Enfermedad Coronaria/diagnóstico , Enfermedad Coronaria/diagnóstico por imagen , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Radiografía , Recurrencia
15.
J Am Coll Cardiol ; 13(7): 1481-91, 1989 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-2656822

RESUMEN

Despite a growing awareness of the correlation of coronary artery stenoses morphology with clinical syndromes, no comprehensive, prospective analysis of the implications of stenosis morphology on risk of myocardial infarction has been reported. Angiograms from 118 patients, representative of the 4.9% of medically treated Coronary Artery Surgery Study (CASS) patients who during subsequent 3 year follow-up study had an anterior myocardial infarction, were matched on the basis of arteriographic anatomy and disease with 141 patients who did not have an anterior infarction. Angiograms from these 259 patients with 557 left anterior descending artery stenoses were reviewed without knowledge of clinical outcome. Conditional regression analyses were performed to determine the importance of stenosis morphology, relative to computer-determined stenosis severity and other clinical variables, in the prediction of risk of infarction. Univariate analysis revealed luminal roughness (odds ratio 4.5; p = 0.001) and lesion length (odds ratio 1.7 per unit length; p = 0.007) to be highly correlated with future risk of infarction. Multivariate analysis revealed left anterior descending artery percent stenosis greater than or equal to 50%, lesion roughness, left circumflex artery stenosis and smoking, in that order, to be predictive of anterior myocardial infarction, whereas 22 other morphologic variables were not independently predictive of outcome. The importance of stenosis roughness may relate to its propensity for thrombogenesis and should be considered in clinical decision making.


Asunto(s)
Angiografía Coronaria , Enfermedad Coronaria/complicaciones , Infarto del Miocardio/etiología , Angiografía , Constricción Patológica/complicaciones , Constricción Patológica/diagnóstico por imagen , Enfermedad Coronaria/diagnóstico por imagen , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Multicéntricos como Asunto , Sistema de Registros , Análisis de Regresión , Factores de Riesgo , Estadística como Asunto
16.
J Am Coll Cardiol ; 4(1): 8-16, 1984 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-6736458

RESUMEN

Several diagnostic noninvasive tests to detect coronary and multivessel coronary disease are available for women. However, all are imperfect and it is not yet clear whether one particular test provides substantially more information than others. The aim of this study was to evaluate clinical findings, exercise electrocardiography, exercise thallium myocardial scintigraphy and cardiac fluoroscopy in 92 symptomatic women without previous infarction and determine which tests were most useful in determining the presence of coronary disease and its severity. Univariate analysis revealed two clinical, eight exercise electrocardiographic, seven myocardial scintigraphic and seven fluoroscopic variables predictive of coronary or multivessel disease with 70% or greater stenosis. The multivariate discriminant function analysis selected a reversible thallium defect, coronary calcification and character of chest pain syndrome (p less than 0.05) as the variables most predictive of presence or absence of coronary disease. The ranked order of variables most predictive of multivessel disease were cardiac fluoroscopy score, thallium score and extent of ST segment depression in 14 electrocardiographic leads. Each provided statistically significant information to the model. The estimate of predictive accuracy was 89% for coronary disease and 97% for multivessel coronary disease. The results suggest that cardiac fluoroscopy or thallium scintigraphy provide significantly more diagnostic information than exercise electrocardiography in women over a wide range of clinical patient subsets.


Asunto(s)
Enfermedad Coronaria/diagnóstico , Prueba de Esfuerzo , Fluoroscopía , Radioisótopos , Talio , Adulto , Anciano , Angina de Pecho/diagnóstico , Angina de Pecho/diagnóstico por imagen , Angiografía Coronaria , Enfermedad Coronaria/diagnóstico por imagen , Vasos Coronarios/diagnóstico por imagen , Electrocardiografía , Femenino , Humanos , Persona de Mediana Edad , Cintigrafía
17.
J Am Coll Cardiol ; 22(4 Suppl A): 14A-19A, 1993 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8376685

RESUMEN

A total of 6,273 consecutive relatively unselected patients with heart failure or left ventricular dysfunction, or both (mean age 62 +/- 12 years, mean ejection fraction 31 +/- 9%), were enrolled in the Studies of Left Ventricular Dysfunction (SOLVD) Registry over a period of 14 months. All patients were followed up for vital status and hospital admissions at 1 year. Ischemic heart disease was the underlying cause of failure or dysfunction in approximately 70% of patients, whereas hypertensive heart disease was considered to be primarily involved in only 7%. There were striking differences in the etiology of heart failure among blacks and whites: 73% of whites had an ischemic etiology of failure versus only 36% of blacks; 32% of blacks had a hypertensive condition versus only 4% of whites. The total 1-year mortality rate was 18%; 19% of patients had hospital admissions for heart failure and 27% either died or had a hospital admission for congestive heart failure during the 1st year of follow-up. Factors related to 1-year mortality or hospital admission for congestive heart failure included age, ejection fraction, diabetes mellitus, atrial fibrillation and female gender. There was no difference in mortality associated with congestive heart failure among blacks and whites, but hospital admissions for heart failure were more frequent in blacks. Digitalis and diuretic agents were the drugs most often used in these patients, who were often taking many medications in relation to severity of congestive heart failure symptoms and ejection fraction.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Insuficiencia Cardíaca/diagnóstico , Pautas de la Práctica en Medicina , Función Ventricular Izquierda , Factores de Edad , Anciano , Bélgica/epidemiología , Canadá/epidemiología , Distribución de Chi-Cuadrado , Femenino , Estudios de Seguimiento , Insuficiencia Cardíaca/tratamiento farmacológico , Insuficiencia Cardíaca/mortalidad , Humanos , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Pautas de la Práctica en Medicina/estadística & datos numéricos , Grupos Raciales , Sistema de Registros/estadística & datos numéricos , Factores de Riesgo , Factores Sexuales , Estados Unidos/epidemiología
18.
J Am Coll Cardiol ; 22(4 Suppl A): 146A-153A, 1993 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8376686

RESUMEN

OBJECTIVES: The aim of this study was to determine the differences in neurohumoral responses between patients with pulmonary congestion with and without impaired left ventricular ejection fraction. BACKGROUND: Previous studies have established the presence of neurohumoral activation in patients with congestive heart failure. It is not known whether the activation of these neurohumoral mechanisms is related to the impairment in systolic contractility. METHODS: The 898 patients recruited into the Studies of Left Ventricular Dysfunction (SOLVD) Registry substudy were examined to identify those patients with pulmonary congestion on chest X-ray film who had either impaired (< or = 45%, group I) or preserved (> 45%, group II) left ventricular ejection fraction. Plasma norepinephrine, plasma renin activity, arginine vasopressin and atrial natriuretic peptide levels were measured in these two groups of patients and compared with values in matched control subjects. RESULTS: Distribution of the New York Heart Association symptom classification was the same in the two groups of patients. Compared with control subjects, patients in group II with pulmonary congestion and preserved ejection fraction had no activation of the neurohumoral mechanisms, except for a small but statistically significant increase in arginine vasopressin and plasma renin activity. Compared with patients in group II, those in group I with pulmonary congestion and impaired ejection fraction had significant increases in plasma norepinephrine (p < 0.002), plasma renin activity (p < 0.02) and atrial natriuretic peptide levels (p < 0.0007). When we controlled for baseline differences between groups I and II, the between-group differences in plasma norepinephrine (p < 0.02) and atrial natriuretic peptide (p < 0.002) remained significant. However, plasma renin activity was not significantly different between groups I and II. When the effects of diuretic agents and angiotensin-converting enzyme inhibitors were adjusted, patients with lower ejection fraction were found to have significantly higher plasma norepinephrine and atrial natriuretic peptide levels. CONCLUSIONS: The results point to the importance of the decrease in left ventricular ejection fraction as one of the mechanisms for activation of neurohormones in patients with heart failure.


Asunto(s)
Insuficiencia Cardíaca/sangre , Hormonas/sangre , Volumen Sistólico , Función Ventricular Izquierda , Adulto , Anciano , Análisis de Varianza , Bélgica , Canadá/epidemiología , Distribución de Chi-Cuadrado , Femenino , Insuficiencia Cardíaca/epidemiología , Insuficiencia Cardíaca/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Estados Unidos/epidemiología
19.
J Am Coll Cardiol ; 22(4): 1141-54, 1993 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8409054

RESUMEN

OBJECTIVES: The Coronary Artery Surgery Study (CASS) required participants to undergo follow-up angiography at 5 years to identify clinical and angiographic features associated with progression of coronary artery disease. BACKGROUND: The CASS randomized 780 patients at 11 participating clinical centers between an initial strategy of medical therapy versus bypass surgery. Five clinical sites accomplished follow-up angiography in > 50% of their randomized subjects within a 42- to 66-month period after the entry arteriogram (n = 314). METHODS: Qualified clinical site angiographers, using side by side film review, evaluated an average of 13 segments/patient on both arteriograms for initial stenosis severity, morphologic features, lesion location and occurrence of disease progression or occlusion. Progression was defined as further definite narrowing by > or = 15% and occlusion as lesion progression to > or = 98%. Lesions were subcategorized as to whether they were univariate and had or had not been treated with bypass surgery. Multivariate logistic regression analyses were performed. RESULTS: For nonbypassed segments, right coronary artery and left anterior descending artery proximal and midlocations were associated with disease progression. For stenosis-containing segments, the initial severity, a non-left anterior descending artery location and increased treadmill duration predicted progression. Segment occlusion was associated with initial lesion severity, right coronary artery location and subsequent interval myocardial infarction. There were few predictors of progression or occlusion in bypassed arteries, other than initial lesion severity. CONCLUSIONS: Univariate and multivariate associations with lesion progression and occlusion included diabetes, lesion location, elevated cholesterol level, interval infarction and lesion morphology. These angiographic results, collected in a prospective trial, are consistent with known risk factors.


Asunto(s)
Angiografía Coronaria , Puente de Arteria Coronaria , Enfermedad Coronaria/diagnóstico por imagen , Enfermedad Coronaria/cirugía , Oclusión de Injerto Vascular/diagnóstico por imagen , Complicaciones Posoperatorias/diagnóstico por imagen , Enfermedad Coronaria/complicaciones , Enfermedad Coronaria/epidemiología , Enfermedad Coronaria/patología , Complicaciones de la Diabetes , Femenino , Estudios de Seguimiento , Oclusión de Injerto Vascular/complicaciones , Oclusión de Injerto Vascular/epidemiología , Oclusión de Injerto Vascular/patología , Humanos , Hipercolesterolemia/complicaciones , Modelos Logísticos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/complicaciones , Variaciones Dependientes del Observador , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/patología , Valor Predictivo de las Pruebas , Pronóstico , Estudios Prospectivos , Recurrencia , Factores de Riesgo , Índice de Severidad de la Enfermedad
20.
J Am Coll Cardiol ; 26(5): 1115-20, 1995 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-7594019

RESUMEN

OBJECTIVES: This study compared functional status in Americans and Canadians with and without prior symptoms of heart disease to separate the effects of medical care from nonmedical factors. BACKGROUND: Coronary angiography and revascularization are used more often in the United States than in Canada, yet rates of mortality and myocardial infarction are similar in the two countries. Recent data suggest that functional status after myocardial infarction is better among Americans than Canadians, but it is uncertain whether this difference is due to medical care or nonmedical factors. METHODS: Quality of life was measured in patients enrolled in seven American and one Canadian site in the Bypass Angioplasty Revascularization Investigation. Prior symptoms of heart disease were defined as angina, myocardial infarction or congestive heart failure before the episode of illness leading to randomization. Functional status was measured with the Duke Activity Status Index and overall emotional and social health using Medical Outcome Study measures on the basis of patient status before the index episode of acute ischemic heart disease. RESULTS: Quality of life was generally better in the 934 Americans than in the 278 Canadians, with overall health rated as excellent or very good in 30% of Americans versus 20% of Canadians (p = 0.0001), higher median Duke Activity Status Index scores (16 vs. 13.5, p = 0.03) but equivalent emotional health (76 vs. 76, p = 0.74) and social health scores (100 vs. 80, p = 0.07). Among the 350 patients without prior symptoms of heart disease, Americans and Canadians had similar overall health, Duke Activity Status Index and emotional and social health scores. However, of the 860 patients with previous symptoms of heart disease, Americans had higher overall health (p = 0.0001) and Duke Activity Status Index scores (p = 0.0008) but similar emotional and social health scores. The results were essentially unchanged after statistical adjustment for potential confounding factors. CONCLUSIONS: The functional status of patients without prior symptoms of heart disease is similar in Americans and Canadians. However, among patients with previous symptomatic heart disease, functional status is higher in Americans than in Canadians. This difference may be due to different patterns of medical management of heart disease in the two countries.


Asunto(s)
Enfermedad Coronaria/fisiopatología , Enfermedad Coronaria/cirugía , Calidad de Vida , Anciano , Angioplastia Coronaria con Balón , Canadá , Puente de Arteria Coronaria , Enfermedad Coronaria/economía , Femenino , Costos de la Atención en Salud , Humanos , Masculino , Persona de Mediana Edad , Resultado del Tratamiento , Estados Unidos
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