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1.
J Mol Model ; 26(5): 95, 2020 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-32266481

RESUMEN

Non-relativistic and Douglas-Kroll-Hess (DKH) basis sets augmented with diffuse functions for He, Ca, Sr, Ba, and lanthanides are generated. These sets are appropriated to describe electrons away from the nuclei. Using the DKH augmented sets along with the B3LYP functional, bond lengths, dissociation energies, harmonic vibrational frequencies, adiabatic ionization potentials, adiabatic electron affinities, and dipole moments for CaH, SrH, and BaH are computed. These results agree well with the most recent experimental and benchmark theoretical data published in the literature. The DKH mean dipole polarizabilities reported in this work for some elements are close to the recommended values. Scalar relativistic effects are also estimated.

2.
J Mol Model ; 25(2): 38, 2019 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-30648221

RESUMEN

Nonrelativistic and relativistic (Douglas-Kroll-Hess, DKH) segmented all-electron Gaussian basis sets of valence triple zeta quality plus polarization functions (TZP) for the lanthanides were developed. As some atomic and molecular properties depend on a good description of the electrons far from the nuclei, these basis sets are augmented with diffuse functions, giving rise to the augmented TZP (ATZP) and ATZP-DKH basis sets. At the DKH level of theory, the B3LYP hybrid functional in conjunction with the TZP-DKH basis set were used to calculate the atomic charges and valence orbital populations of the lanthanide and oxygen atoms, the bond lengths, and the equilibrium dissociation energies of lanthanide monoxides. The DKH-B3LYP/ATZP-DKH polarizability of Yb and the DKH-M06/TZP-DKH first ionization energies of the lanthanides are also reported. Compared with the values obtained with a larger all-electron basis set, and theoretical and experimental data found in the literature, data obtained by our compact basis sets are verified to be accurate and reliable. Unlike effective core potential valence basis sets, our basis sets can also be employed in molecular property calculations that involve the simultaneous treatment of core and valence electrons. Graphical abstract ᅟ.

3.
J Comput Chem ; 39(20): 1561-1567, 2018 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-29676469

RESUMEN

A detailed analysis of the electronic structure of the ground and first excited spin state of three diatomic molecules ( N2, BH and CO) under static applied electric field is performed at CCSD(T), DFT, MRCI and MRCI(Q) levels of theory. Our findings have revealed that by boosting the applied field one induces changes in the occupation numbers of molecular orbitals, giving rise to changes in the equilibrium geometry and in the HOMO-LUMO energy gap. Specifically, singlet to triplet spin transition can be induced by increasing the applied electric field beyond a critical value. Accordingly, affecting the accuracy of the widely used expression of energy expanded in Taylor series with respect to the applied electric field. © 2018 Wiley Periodicals, Inc.

4.
Ann Thorac Surg ; 70(1): 169-74, 2000 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10921703

RESUMEN

BACKGROUND: Risk factors for 30-day hospital readmission following coronary artery bypass grafting (CABG) have not been established. METHODS: We prospectively followed 485 consecutive patients who underwent isolated primary CABG at our institution in 1997. Patients were contacted by telephone at 30 days following operation to determine readmission status. RESULTS: The overall readmission rate was 16% (76 of 485). Female gender (25% versus 11%, p = 0.001) and diabetes (22% versus 12%, p = 0.005) were associated with significantly higher readmission rates. The relationship between female gender and readmission persisted after correcting for age and other comorbidities. Congestive heart failure trended towards a significant relationship with increased readmission rate (22% versus 14%, p = 0.09). There were no significant associations between 30-day readmission rate and age, hypertension, chronic obstructive pulmonary disease, history of myocardial infarction, peripheral vascular disease, creatinine level of > or = 1.4 mg/dL, or decreased left ventricular ejection fraction (< 40%). CONCLUSIONS: These data show that most of the classic risk factors for postoperative mortality are not necessarily associated with increased readmission. However, female gender and diabetes are associated with greater than twice the risk of 30-day readmission following CABG.


Asunto(s)
Puente de Arteria Coronaria , Readmisión del Paciente/estadística & datos numéricos , Complicaciones Posoperatorias/epidemiología , Anciano , Femenino , Estudios de Seguimiento , Humanos , Masculino , Pronóstico , Estudios Prospectivos , Factores de Riesgo , Factores de Tiempo
5.
Surgery ; 126(2): 184-90, 1999 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10455882

RESUMEN

BACKGROUND: Female gender is an established risk factor for increased mortality and morbidity after coronary artery bypass graft (CABG) surgery. However, the impact of gender on functional outcome after CABG is not well established. METHODS: Functional status was assessed at baseline and at 6 months with the Duke Activity Status Index (DASI) in 196 consecutive patients undergoing isolated primary CABG. Follow-up data were complete in 158 (81%) patients. The functional status of the 54 (34%) female and the 104 (66%) male patients was compared. RESULTS: The mean DASI score was significantly lower in women at baseline (19.3 +/- 13.8 vs 28.3 +/- 16.8, P = .001) and at 6 months (22.7 +/- 16.3 vs 32.8 +/- 18.2, P = .0007); however, the 6-month change in DASI score (3.3 +/- 16.9 vs 4.5 +/- 20.0, P = .7) was comparable. A similar proportion of women and men (54% vs 53%) had improved above their baseline functional level at 6 months. CONCLUSIONS: These data demonstrate that women undergo CABG at a significantly lower functional level than men; however, the functional improvement after CABG is similar across genders.


Asunto(s)
Actividades Cotidianas , Puente de Arteria Coronaria/rehabilitación , Adulto , Anciano , Puente de Arteria Coronaria/mortalidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Factores Sexuales
6.
Circulation ; 98(19 Suppl): II35-40, 1998 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-9852877

RESUMEN

BACKGROUND: Intense medical and economic pressures have created "fast track" cardiac surgery in which clinical services are streamlined and early discharge is encouraged. Does this strategy promote significant cost saving or merely cost shifting? In a global system of reimbursement, the economic benefit of decreasing patient length of stay may be offset by high rates of patient readmission. This study was undertaken to determine the 30-day readmission rate after cardiac surgery and to analyze trends of readmission diagnoses. METHODS AND RESULTS: From October 1, 1996 to July 31, 1997, 460 consecutive cardiac surgical operations were performed at 1 institution. There were 25 deaths and 8 patients who remained as inpatients at the 30-day postoperative deadline for readmission. Two patients had 2 operations. Therefore, 527 operations were performed on 525 patients. There were 110 readmissions after 527 operations for a readmission rate of 20.9%. A significant number of readmissions (49%) were to outside hospitals. Readmission diagnoses were: atrial fibrillation (23%); angina, congestive heart failure, or ventricular tachycardia (20%); leg wound (15%); sternal wound (5%); pneumonia (5%); gastrointestinal complaints (5%); neurologic event (2%); and miscellaneous (25%). Patients discharged > or = 7 days postoperatively were twice as likely to be readmitted as those discharged on postoperative days 4, 5, or 6. CONCLUSIONS: Readmission after cardiac surgery is common and frequently (49%) to outside institutions. Patients discharged > or = 7 days postoperatively represent the patients at greatest risk of readmission and, therefore, warrant closer scrutiny before discharge.


Asunto(s)
Procedimientos Quirúrgicos Cardíacos/economía , Control de Costos , Hospitalización , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Femenino , Humanos , Tiempo de Internación , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/clasificación , Periodo Posoperatorio , Reoperación
7.
Ann Thorac Surg ; 66(4): 1306-11, 1998 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9800825

RESUMEN

BACKGROUND: To assess the impact of central venous pressure catheter monitoring in low-risk coronary artery bypass grafting (CABG), we compared the hospital course of patients undergoing CABG with central venous pressure catheter monitoring with that of similar patients undergoing CABG with pulmonary artery catheter monitoring. METHODS: All isolated primary CABG procedures (n = 312) performed between April 22 and October 31, 1996, were evaluated, and 194 patients meeting six central venous pressure catheter use criteria were identified. Of these 194 patients, 133 (68%) underwent CABG with central venous pressure catheter monitoring, and 61 (32%) had pulmonary artery catheter monitoring owing to surgeon or anesthesiologist preference. RESULTS: In-hospital mortality was similar. A trend toward increased overall complications was seen in the pulmonary artery catheter group. The total volume infused in the first 12 hours, the 24-hour weight gain, and the intubation time were significantly greater in the pulmonary artery catheter group. Increases in intensive care unit length of stay and in total hospital charges trended toward statistical significance in the pulmonary artery catheter group. CONCLUSIONS: Pulmonary artery catheter use in low-risk patients undergoing CABG was associated with greater weight gain and longer intubation time and may be associated with increased morbidity and utilization of hospital resources.


Asunto(s)
Cateterismo Venoso Central , Puente de Arteria Coronaria , Anciano , Cateterismo Venoso Central/efectos adversos , Cateterismo Venoso Central/estadística & datos numéricos , Cateterismo de Swan-Ganz/efectos adversos , Cateterismo de Swan-Ganz/estadística & datos numéricos , Presión Venosa Central , Femenino , Precios de Hospital/estadística & datos numéricos , Mortalidad Hospitalaria , Humanos , Tiempo de Internación/estadística & datos numéricos , Modelos Lineales , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/epidemiología , Estudios Retrospectivos
8.
J Surg Res ; 76(2): 124-30, 1998 May.
Artículo en Inglés | MEDLINE | ID: mdl-9698511

RESUMEN

BACKGROUND: Diabetes has been shown to have a negative impact on mortality following coronary artery bypass graft (CABG) surgery. This analysis examines the impact of diabetes on additional clinical and economic outcomes. MATERIAL AND METHODS: Between May and October of 1996, 312 consecutive patients undergoing isolated primary CABG were followed through hospital discharge. A total of 114 diabetics (37%) and 198 nondiabetics (63%) was evaluated. Among the diabetics, 62 (54%) were insulin requiring and 52 (46%) were treated with oral hypoglycemic agents or with diet alone. RESULTS: The incidences of major clinical complications including death, renal failure, stroke, reexploration for bleeding, and mediastinitis or sternal dehiscence were not significantly different among insulin-requiring diabetics, noninsulin-requiring diabetics, and nondiabetics. However, insulin-requiring diabetics had a significantly longer (P < 0.01) total length of stay compared to both noninsulin-requiring diabetics and nondiabetics (107 +/- 12.7 days vs. 5.6 +/- 1.5 days vs. 6.8 +/- 5.4 days, respectively), a significantly longer (P < 0.01) intensive care unit length of stay (5.3 +/- 12.4 days vs. 1.4 +/- 0.8 days vs. 2.0 +/- 3.9 days, respectively), and significantly greater (P, 0.01) total hospital charges (48.7 +/- 56.1 thousand dollars vs. 29.3 +/- 4.3 thousand dollar vs. 32.9 +/- 18.9 thousand dollars, respectively). There were no significant differences between the noninsulin-requiring diabetics and the nondiabetics with regard to these clinical and economic outcomes. CONCLUSIONS: Diabetics treated with oral hypoglycemic agents or with diet alone have clinical and economic outcomes similar to nondiabetics following CABG. Insulin-requiring diabetes, however, predicts significantly increased hospital resource utilization. Future outcome assessment and resource utilization analyses must stratify diabetes by treatment to be completely accurate.


Asunto(s)
Puente de Arteria Coronaria , Angiopatías Diabéticas/economía , Angiopatías Diabéticas/cirugía , Anciano , Trastornos Cerebrovasculares , Diabetes Mellitus Tipo 1/complicaciones , Diabetes Mellitus Tipo 1/economía , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/economía , Angiopatías Diabéticas/mortalidad , Costos de la Atención en Salud , Humanos , Unidades de Cuidados Intensivos , Tiempo de Internación , Mediastinitis , Persona de Mediana Edad , Complicaciones Posoperatorias , Hemorragia Posoperatoria , Insuficiencia Renal
9.
Atherosclerosis ; 138(2): 391-401, 1998 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9690924

RESUMEN

The objective of this study was to assess the percent stenosis of the culprit lesion responsible for subsequent myocardial infarction in the Program on the Surgical Control of the Hyperlipidemias (POSCH). It is unknown if the susceptible coronary artery culprit lesion responsible for an acute myocardial infarction is relatively large ( > or = 50% arteriographic stenosis) and hemodynamically significant ( > or = 70% stenosis), or small ( < 50%, stenosis) and asymptomatic. Certain necropsy and arteriography studies support the large progenitor lesion concept, and other arteriography studies support the small lesion hypothesis. We analyzed the coronary arteriogram immediately preceding a Q wave (transmural) myocardial infarction for the degree of stenosis of the suspected culprit lesion, which was selected by visual inspection of the coronary circulation supplying the electrocardiogram-defined area of myocardial infarction. There was no perceptible difference with respect to vessel segment distribution of culprit lesions or time to infarction between the 52 control-group patients and the 27 intervention-group patients. For the two groups combined (n=79), the predominantly involved segments were the middle right coronary artery and the proximal left anterior descending coronary artery. The time interval from the preceding coronary arteriogram closest to the index myocardial infarction ranged from 0 days to 10 years; however, 64.6% of the arteriograms were performed 2 years or less prior to the myocardial infarction. Only 5.1% of the patients in both groups combined had a culprit lesion stenosis < 50%, while 88.6% of the patients in both groups combined had a culprit lesion stenosis > or = 70%. The results strongly favor the large lesion hypothesis of causation for myocardial infarction. It is premature, however, to state that the relative size of the culprit lesion has been indisputably determined. The resolution of this problem has exceedingly important practical implications for the management of patients with known atherosclerotic coronary heart disease and for those asymptomatic individuals with silent atherosclerotic coronary heart disease.


Asunto(s)
Enfermedad Coronaria , Infarto del Miocardio/etiología , Adulto , Angiografía Coronaria , Enfermedad Coronaria/complicaciones , Enfermedad Coronaria/diagnóstico por imagen , Enfermedad Coronaria/patología , Enfermedad Coronaria/fisiopatología , Humanos , Persona de Mediana Edad , Factores de Riesgo
10.
Arch Intern Med ; 158(11): 1253-61, 1998 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-9625405

RESUMEN

BACKGROUND: In 1990, when the Program on the Surgical Control of the Hyperlipidemias (POSCH) reported its in-trial results strongly supporting the conclusion that effective lipid modification reduces progression of atherosclerosis, the differences for the end points of overall mortality and mortality from atherosclerotic coronary heart disease (ACHD) did not reach statistical significance. METHODS: The Program on the Surgical Control of the Hyperlipidemias recruited men and women with a single documented myocardial infarction between the ages of 30 and 64 years who had a plasma cholesterol level higher than 5.69 mmol/L (220 mg/dL) or higher than 5.17 mmol/L (200 mg/dL) if the low-density lipoprotein cholesterol level was in excess of 3.62 mmol/L (140 mg/dL). Between 1975 and 1983, 838 patients were randomized: 417 to the diet control group and 421 to the diet plus partial ileal bypass intervention group. Mean patient follow-up for this 5-year posttrial report was 14.7 years (range, 12.2-20 years). RESULTS: At 5 years after the trial, statistical significance was obtained for differences in overall mortality (P = .049) and mortality from ACHD (P = .03). Other POSCH end points included overall mortality (left ventricular ejection fraction > or =50%) (P = .01), mortality from ACHD (left ventricular ejection fraction > or =50%) (P = .05), mortality from ACHD and confirmed nonfatal myocardial infarction (P<.001), confirmed nonfatal myocardial infarction (P<.001), mortality from ACHD, confirmed and suspected myocardial infarction and unstable angina (P<.001), incidence of coronary artery bypass grafting or percutaneous transluminal coronary angioplasty (P<.001), and onset of clinical peripheral vascular disease (P = .02). There were no statistically significant differences between groups for cerebrovascular events, mortality from non-ACHD, and cancer. All POSCH patients have been available for follow-up. CONCLUSION: At 5 years after the trial, all POSCH mortality and atherosclerosis end points, including overall mortality and mortality from ACHD, demonstrated statistically significant differences between the study groups.


Asunto(s)
Enfermedad de la Arteria Coronaria/mortalidad , Derivación Yeyunoileal , LDL-Colesterol/sangre , Enfermedad de la Arteria Coronaria/sangre , Enfermedad de la Arteria Coronaria/complicaciones , Enfermedad de la Arteria Coronaria/prevención & control , Femenino , Estudios de Seguimiento , Humanos , Lípidos/sangre , Masculino , Persona de Mediana Edad , Morbilidad , Estudios Multicéntricos como Asunto , Ensayos Clínicos Controlados Aleatorios como Asunto
12.
Surgery ; 120(4): 672-9, 1996 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8862377

RESUMEN

BACKGROUND: Few lipid/atherosclerosis intervention trials have assessed the impact of cholesterol reduction on peripheral arterial disease. The 838 patients evaluated in the Program on the Surgical Control of the Hyperlipidemias (POSCH) trial represent more than the total number of patients in the seven previously reported studies. METHODS: Peripheral arterial disease in POSCH was assessed by progression of clinical disease, serial changes in the systolic blood pressure ankle/brachial index (ABI), and changes on sequential peripheral arteriograms. RESULTS: At the time of formal closure of the POSCH trial on July 19, 1990, claudication or limb-threatening ischemia was exhibited in 72 of 417 control group (CG) patients and in 54 of 421 intervention group (IG) patients (IG relative risk [RR] 0.702, 95% confidence interval [CI] 0.169 to 1.000, p = 0.049). With additional follow-up evaluation to September 30, 1994, clinical peripheral arterial disease was evident in 91 CG patients and 64 IG patients (RR 0.656, 95% CI 0.200 to 0.903, p = 0.009). At the 5-year follow-up evaluation, an ABI of less than 0.95 was present in 41 of 120 CG patients and in 24 of 126 IG patients, all of whom had an ABI of 0.95 or greater at baseline (RR in the IG of 0.557, 95% CI 0.360 to 0.863, p < 0.01). No appreciable differences were noted in the progression or regression of arteriographic peripheral arterial disease between the two groups. CONCLUSIONS: Effective cholesterol reduction in POSCH led to statistically significant differences between the control and the intervention groups in the development of clinically evident peripheral arterial disease and in the ABI values, but not in the peripheral arteriograms. Additional studies need to assess the correlation between peripheral arterial changes and coronary arterial changes and clinical atherosclerosis events. Intervention trials that study peripheral arterial disease have intrinsic value in the evaluation of the impact of risk factor modification on progression of atherosclerotic peripheral arterial disease.


Asunto(s)
Arteriosclerosis/cirugía , Colesterol/metabolismo , Hiperlipidemias/cirugía , Angiografía , Arteriosclerosis/mortalidad , Arteriosclerosis/terapia , Humanos , Hiperlipidemias/mortalidad , Hiperlipidemias/terapia , Estudios Longitudinales , Análisis de Supervivencia
13.
Ann Surg ; 224(4): 486-98; discussion 498-500, 1996 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8857853

RESUMEN

OBJECTIVE: The authors assessed the clinical results of lipid-lowering therapy in women. SUMMARY BACKGROUND DATA: The Program on the Surgical Control of the Hyperlipidemias (POSCH) has demonstrated that effective lowering of total cholesterol and low-density lipoprotein cholesterol in a postmyocardial infarction population significantly reduces atherosclerotic coronary heart disease (ACHD) mortality, ACHD mortality combined with a new confirmed nonfatal myocardial infarction, and the number of coronary artery bypass grafting and angioplasty procedures performed. METHODS: A review and meta-analysis were performed of the seven primary or secondary lipid/ atherosclerosis intervention trials-including POSCH-published in the English-language literature that included women and published results in women separate from the results in men or in the entire trial population. The main outcome measure analyzed was overall mortality. RESULTS: The Scottish Physicians Clofibrate Study, the Newcastle upon Tyne Clofibrate Study, and the Pravastatin Limitation of Atherosclerosis in the Coronary Arteries (PLAC I) Trial may have demonstrated a possible benefit in ACHD prognosis from effective lipid intervention in women. The other four available trials did not. The Minnesota Coronary Survey reported a 15.6% increase in overall mortality rate and a 30.6% increase in a combined cardiovascular endpoint rate in the lipid-intervention group. The Upjohn Colestipol Study demonstrated statistically significant reductions in overall and ACHD mortality in the men, but not in the women. The Scandinavian.


Asunto(s)
Hiperlipidemias/cirugía , Íleon/cirugía , Colesterol/sangre , Ensayos Clínicos Controlados como Asunto , Enfermedad de la Arteria Coronaria/mortalidad , Enfermedad de la Arteria Coronaria/prevención & control , Femenino , Humanos , Hiperlipidemias/sangre , Hiperlipidemias/tratamiento farmacológico , Hipolipemiantes/uso terapéutico , Masculino , Factores de Riesgo , Tasa de Supervivencia
14.
Ann Thorac Surg ; 62(3): 818-22; discussion 822-3, 1996 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8815822

RESUMEN

BACKGROUND: This study was designed to evaluate the clinical accuracy of multiplanar reconstructions and three-dimensional shaded surface displays compared with conventional transaxial computed tomography, bronchoscopy, and surgical pathologic findings. METHODS: Transaxial computed tomographic images, two-dimensional nonstandard multiplanar reconstruction images, and three-dimensional images obtained from patients with tracheobronchial disease were prospectively evaluated for the relationship to adjacent structures, lesion characterization, and surgical anatomic correlation before invasive procedures. RESULTS: Compared with conventional transaxial computed tomographic images, multiplanar reconstructions and three-dimensional shaded surface displays provided a correlative map of bronchoscopic and surgical anatomy in patients with benign and malignant tracheobronchial pathology. The longitudinal extent of abnormalities are better demonstrated on the multiplanar reconstruction and three-dimensional images, whereas the transverse extent of disease and relationships to adjacent structures were better shown on axial computed tomographic sections. CONCLUSIONS: Three-dimensional and multiplanar two-dimensional images are additive to transaxial computed tomography for evaluation of diseases involving the central airways. They are beneficial for planning invasive procedures. More importantly, they provide consistent, highly accurate measurements for routine follow-up and for future clinical trials.


Asunto(s)
Escoliosis/cirugía , Vértebras Torácicas/cirugía , Toracotomía/métodos , Grabación en Video , Adolescente , Niño , Femenino , Humanos , Mediciones del Volumen Pulmonar , Masculino , Complicaciones Posoperatorias
15.
Ann Thorac Surg ; 62(3): 811-7, 1996 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8784012

RESUMEN

BACKGROUND: This study was designed to evaluate the clinical accuracy of multiplanar reconstructions and three-dimensional shaded surface displays compared with conventional transaxial computed tomography, bronchoscopy, and surgical pathologic findings. METHODS: Transaxial computed tomographic images, two-dimensional nonstandard multiplanar reconstruction images, and three-dimensional images obtained from patients with tracheobronchial disease were prospectively evaluated for the relationship to adjacent structures, lesion characterization, and surgical anatomic correlation before invasive procedures. RESULTS: Compared with conventional transaxial computed tomographic images, multiplanar reconstructions and three-dimensional shaded surface displays provided a correlative map of bronchoscopic and surgical anatomy in patients with benign and malignant tracheobronchial pathology. The longitudinal extent of abnormalities are better demonstrated on the multiplanar reconstruction and three-dimensional images, whereas the transverse extent of disease and relationships to adjacent structures were better shown on axial computed tomographic sections. CONCLUSIONS: Three-dimensional and multiplanar two-dimensional images are additive to transaxial computed tomography for evaluation of diseases involving the central airways. They are beneficial for planning invasive procedures. More importantly, they provide consistent, highly accurate measurements for routine follow-up and for future clinical trials.


Asunto(s)
Enfermedades Bronquiales/diagnóstico por imagen , Procesamiento de Imagen Asistido por Computador , Tomografía Computarizada por Rayos X , Enfermedades de la Tráquea/diagnóstico por imagen , Anciano , Anciano de 80 o más Años , Broncografía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Tomografía Computarizada por Rayos X/métodos , Tráquea/diagnóstico por imagen
16.
J Am Coll Cardiol ; 26(2): 351-7, 1995 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-7608434

RESUMEN

OBJECTIVES: We sought to analyze the disease-free intervals and calculate the freedom from atherosclerosis events in the Program on the Surgical Control of the Hyperlipidemias (POSCH). BACKGROUND: The POSCH study was a randomized, secondary lipid/atherosclerosis intervention trial that provided strong evidence for reduction in atherosclerosis progression as demonstrated by clinical and arteriographic end points. The 417 control group patients received American Heart Association phase II diet instruction, and the 421 intervention group patients received identical dietary instruction and underwent a partial ileal bypass operation. METHODS: Four outcome measures were determined: 1) overall mortality, 2) coronary heart disease mortality, 3) coronary heart disease mortality and confirmed nonfatal myocardial infarction, and 4) coronary/cardiac interventions. RESULTS: An overall mortality rate of 10% occurred at 6.7 years in the control group and 9.4 years in the intervention group, for a gain in disease-free interval of 2.7 years in the intervention group (p = 0.032). A coronary heart disease mortality rate of 8% occurred at 7.2 years in the control group and 11 years in the intervention group, for a gain of 3.8 years (p = 0.046). Twenty percent of patients demonstrated the combined end point of coronary heart disease mortality and confirmed nonfatal myocardial infarction at 5.9 years in the control group and 11.4 years in the intervention group, for a gain of 5.5 years (p < 0.001). Twenty-five percent of patients underwent either coronary artery bypass graft surgery, percutaneous transluminal coronary angioplasty or heart transplantation at 5.4 years in the control group and 12.4 years in the intervention group, for a gain of 7 years (p < 0.001). CONCLUSIONS: The marked lipid modification achieved by partial ileal bypass in the POSCH trial led to demonstrable increases in the disease-free intervals for overall mortality, coronary heart disease mortality, coronary heart disease mortality and confirmed nonfatal myocardial infarction, and coronary intervention procedures. For the clinician and the patient, estimation of disease-free intervals may be more relevant than assessment of differences in incidence rates and risk ratios.


Asunto(s)
Arteriosclerosis/cirugía , Enfermedad Coronaria/mortalidad , Hipercolesterolemia/cirugía , Derivación Yeyunoileal , Adulto , Arteriosclerosis/dietoterapia , Arteriosclerosis/etiología , Terapia Combinada , Enfermedad Coronaria/etiología , Interpretación Estadística de Datos , Supervivencia sin Enfermedad , Femenino , Humanos , Hipercolesterolemia/complicaciones , Hipercolesterolemia/dietoterapia , Tablas de Vida , Masculino , Persona de Mediana Edad
17.
Am Heart J ; 129(4): 656-62, 1995 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-7900613

RESUMEN

The purpose of this study was to examine the effects of aspirin use on mortality and morbidity rates in a subset of the control group of the Program on the Surgical Control of the Hyperlipidemias (POSCH) that was stratified by cigarette smoking status at the time of randomization. The clinical impact of aspirin intake in cigarette smokers and former cigarette smokers has not been well studied. POSCH was a randomized, controlled, clinical trial designed to ascertain the effects of lipid modification by the partial ileal bypass operation on clinical end-points and arteriographic changes in postmyocardial infarction subjects with hypercholesterolemia. Cohorts of cigarette smokers in the diet-control group were evaluated for overall and atherosclerotic coronary heart disease (ACHD) mortality rates and recurrent confirmed nonfatal myocardial infarction rates. In current cigarette smokers at baseline (n = 90) with a mean follow-up of 8.3 years, the overall mortality rate was 45.2% in patients with no aspirin use and 10.4% in patients who reported even infrequent aspirin use (relative risk = 4.3, 95% confidence interval (CI) = 2.4 to 10.6, p < 0.001). For ACHD mortality in this cohort, the relative risk was 17.1 (35.7% vs 2.1%, 95% CI = 1.4 to 125.0, p < 0.001); for the combined end-point of ACHD mortality and nonfatal myocardial infarction, the relative risk was 2.4 (40.5% vs 16.7%, 95% CI = 1.2 to 5.1, p = 0.018).(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Aspirina/uso terapéutico , Infarto del Miocardio/mortalidad , Fumar/mortalidad , Estudios de Cohortes , Enfermedad de la Arteria Coronaria/epidemiología , Enfermedad de la Arteria Coronaria/mortalidad , Femenino , Estudios de Seguimiento , Humanos , Hipercolesterolemia/cirugía , Masculino , Persona de Mediana Edad , Infarto del Miocardio/epidemiología , Recurrencia , Análisis de Regresión , Factores de Riesgo , Fumar/epidemiología , Cese del Hábito de Fumar
18.
J Clin Epidemiol ; 48(3): 389-405, 1995 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-7897460

RESUMEN

The Program on the Surgical Control of the Hyperlipidemias (POSCH) was a secondary atherosclerosis intervention trial employing partial ileal bypass surgery as the intervention modality. For this report, we analyzed 105 subgroups in 35 variables in POSCH, chosen predominantly for their potential relationship to the risk of atherosclerotic coronary heart disease (ACHD). We defined potential differential effects as those with: (1) an absolute z-value > or = 2.0 for the subgroup, if the absolute z-value for the overall effect was < 2.0; and (2) an absolute z-value > or = 3.0 for the subgroup and a relative risk < or = 0.5, if the absolute z-value for the overall effect was > or = 2.0. For each of three major POSCH endpoints of overall mortality, ACHD mortality and ACHD mortality or confirmed nonfatal myocardial infarction, we found seven subgroups with a differential risk reduction in the surgery group as compared to the control group. Allowing for identical subgroups for more than one endpoint, there were 13 individual subgroups with differential effects. Of these, seven demonstrated internal consistency across endpoints, and five of these seven displaced external consistency with known ACHD risk factors and for biological plausibility: triglyceride concentration > or = 200 mg/dl; cigarette smoking; overt or borderline diabetes mellitus; a Minnesota ECG Q-QS code of 1-1; and obesity. A greater risk reduction, in comparison to the overall treatment effect, by the reduction of a single risk factor, hypercholesterolemia, in patients with at least two major ACHD risk factors was a provocative and an hypothesis-generating outcome of this analysis. The clinical implications of this finding may lead to more aggressive cholesterol intervention in patients with multiple ACHD risk factors.


Asunto(s)
Enfermedad de la Arteria Coronaria/mortalidad , Hiperlipidemias/cirugía , Derivación Yeyunoileal , Mortalidad , Infarto del Miocardio/epidemiología , Adulto , Antropometría , Colesterol/sangre , Electrocardiografía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Evaluación de Programas y Proyectos de Salud , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Riesgo , Estados Unidos/epidemiología
19.
J Cardiovasc Pharmacol ; 25 Suppl 4: S3-10, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-8907208

RESUMEN

The Program on the Surgical Control of the Hyperlipidemias (POSCH), a randomized clinical trial, tested the hypothesis that cholesterol modification induced by partial ileal bypass would favorably affect mortality and morbidity due to coronary heart disease (CHD). The study population consisted of 838 patients (417 in the control group and 421 in the surgery group) in four clinical centers, both men (90.7%) and women with an average age of 51 years who had survived a first myocardial infarction. The lipid changes in POSCH have been the most marked in any atherosclerosis intervention trial utilizing a single mode of intervention in addition to diet therapy. At 5 years, the surgery group, compared with the control group, had a 23.3 +/- 1.0% (mean +/- SE) lower total plasma cholesterol level (p < 0.0001), a 37.7 +/- 1.2% lower low-density lipoprotein cholesterol level (p < 0.0001), and a 4.3 +/- 1.8% higher high-density lipoprotein cholesterol level (p = 0.02). For the combined end point of CHD mortality and confirmed nonfatal myocardial infarction, there was a 35.0% reduction in the surgery group (p < 0.001). Coronary artery bypass grafting was reduced in the surgery group by 62.0% (p < 0.0001) and percutaneous transluminal coronary angioplasty was reduced by 55.0% (p < 0.01). A comparison of baseline coronary arteriograms with those obtained at 3, 5, 7, and 10 years consistently showed less atherosclerosis disease progression (p < 0.001) and greater atherosclerosis disease regression at 5 and 7 years (p < 0.01) in the surgery group. At formal trial completion in July 1990, the overall mortality in the surgery subgroup with an ejection fraction of 50% or greater was 36.1% lower (p = 0.02). During subsequent follow-up, trends toward statistical significance for differences in both CHD and in overall mortality have become evident. The POSCH results provide strong support for beneficial clinical and arteriographic reduction of atherosclerosis progression after lipid modification by partial ileal bypass.


Asunto(s)
Colesterol/sangre , Enfermedad Coronaria/mortalidad , Hiperlipidemias/cirugía , Derivación Yeyunoileal , Adulto , Anciano , Angiografía , Arteriosclerosis/cirugía , Arteriosclerosis/terapia , LDL-Colesterol/sangre , Puente de Arteria Coronaria , Enfermedad Coronaria/terapia , Femenino , Estudios de Seguimiento , Humanos , Hiperlipidemias/dietoterapia , Masculino , Persona de Mediana Edad , Infarto del Miocardio/fisiopatología , Volumen Sistólico/fisiología
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