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1.
J Nucl Med ; 49(10): 1636-42, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18794266

RESUMEN

UNLABELLED: Gated myocardial perfusion SPECT allows calculation of end-diastolic and end-systolic volumes (EDV and ESV, respectively) and left ventricular ejection fraction (LVEF). The quantification algorithms QGS (quantitative gated SPECT), 4D-MSPECT, and CARE heart show a good correlation with cardiac MRI. Nevertheless, differences in contour finding suggest algorithm-specific effects if heart axes vary. The effect of tilting heart axes on gated SPECT was quantified as a possible source of error. METHODS: Sixty men underwent gated SPECT (450 MBq of (99m)Tc-tetrofosmin or sestamibi, 8 gates/cycle). After correct reorientation (R(0)), datasets were tilted by 5 degrees , 10 degrees , 15 degrees , 20 degrees , 30 degrees , and 45 degrees along both long axes (R(5), R(10), R(15), R(20), R(30), and R(45), respectively). EDV, ESV, and LVEF were calculated using QGS, 4D-MSPECT, and CARE heart. Because a 15 degrees tilt could be a maximum possible misreorientation in routine, R(0) and R(15) results were analyzed in detail. Absolute-difference values between results of tilted and correctly reoriented datasets were calculated for all tilts and algorithms. RESULTS: QGS and CARE heart succeeded for R(0) and R(15) in all cases, whereas 4D-MSPECT failed to find the basal plane in 1 case (patient B). R(2) values between paired R(15)/R(0) results were 0.992 (QGS), 0.796 (4D-MSPECT; R(2) = 0.919 in n = 59 after exclusion of the failed case), and 0.916 (CARE heart) for EDV; 0.994 (QGS), 0.852 (4D-MSPECT; R(2) = 0.906 in n = 59), and 0.899 (CARE heart) for ESV; and 0.988 (QGS), 0.814 (4D-MSPECT; R(2) = 0.810 in n = 59), and 0.746 (CARE heart) for LVEF. Concerning all levels of misreorientation, 1 patient was excluded for all algorithms because of multiple problems in contour finding; additionally for 4D-MSPECT patient B was excluded. In the 45 degrees group, QGS succeeded in 58 of 59 cases, 4D-MSPECT in 58 of 58, and CARE heart in 33 of 59. Mean absolute differences for EDV ranged from 5.1 +/- 4.1 to 12.8 +/- 10.5 mL for QGS, from 6.7 +/- 6.3 to 34.2 +/- 20.7 mL for 4D-MSPECT, and from 5.4 +/- 5.6 to 25.2 +/- 16.1 mL for CARE heart (tilts between 5 degrees and 45 degrees ). Mean absolute differences for ESV ranged from 4.1 +/- 3.7 to 8.0 +/- 9.4 mL for QGS, from 5.6 +/- 8.0 to 10.0 +/- 10.5 mL for 4D-MSPECT, and from 5.4 +/- 5.6 to 25.5 +/- 16.1 mL for CARE heart. Mean absolute differences for LVEF ranged from 1.1% +/- 1.0% to 2.2% +/- 1.8% for QGS, from 4.0% +/- 3.5% to 8.0% +/- 7.1% for 4D-MSPECT, and from 3.4% +/- 2.9% to 9.2% +/- 6.0% for CARE heart. CONCLUSION: Despite tilted heart axes, QGS showed stable results even when using tilts up to 45 degrees . 4D-MSPECT and CARE heart results varied with reorientation of the heart axis, implying that published validation results apply to correctly reoriented data only.


Asunto(s)
Ventrículos Cardíacos/diagnóstico por imagen , Ventrículos Cardíacos/patología , Miocardio/patología , Compuestos Organofosforados/farmacocinética , Compuestos de Organotecnecio/farmacocinética , Tecnecio Tc 99m Sestamibi/farmacocinética , Tomografía Computarizada de Emisión de Fotón Único/instrumentación , Tomografía Computarizada de Emisión de Fotón Único/métodos , Adulto , Anciano , Algoritmos , Imagen de Acumulación Sanguínea de Compuerta/métodos , Humanos , Procesamiento de Imagen Asistido por Computador , Masculino , Persona de Mediana Edad , Perfusión , Radiofármacos/farmacocinética
2.
Crit Care ; 12(4): R92, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18638367

RESUMEN

INTRODUCTION: The purpose of this study was to investigate the costs and health status outcomes of intensive care unit (ICU) admission in patients who present after sudden cardiac arrest with in-hospital or out-of-hospital cardiopulmonary resuscitation. METHODS: Five-year survival, health-related quality of life (Medical Outcome Survey Short Form-36 questionnaire, SF-36), ICU costs, hospital costs and post-hospital health care costs per survivor, costs per life year gained, and costs per quality-adjusted life year gained of patients admitted to a single ICU were assessed. RESULTS: One hundred ten of 354 patients (31%) were alive 5 years after hospital discharge. The mean health status index of 5-year survivors was 0.77 (95% confidence interval 0.70 to 0.85). Women rated their health-related quality of life significantly better than men did (0.87 versus 0.74; P < 0.05). Costs per hospital discharge survivor were 49,952 euro. Including the costs of post-hospital discharge health care incurred during their remaining life span, the total costs per life year gained were 10,107 euro. Considering 5-year survivors only, the costs per life year gained were calculated as 9,816 euro or 14,487 euro per quality-adjusted life year gained. Including seven patients with severe neurological sequelae, costs per life year gained in 5-year survivors increased by 18% to 11,566 euro. CONCLUSION: Patients who leave the hospital following cardiac arrest without severe neurological disabilities may expect a reasonable quality of life compared with age- and gender-matched controls. Quality-adjusted costs for this patient group appear to be within ranges considered reasonable for other groups of patients.


Asunto(s)
Costos de la Atención en Salud , Paro Cardíaco/economía , Paro Cardíaco/terapia , Unidades de Cuidados Intensivos/economía , Admisión del Paciente/economía , Calidad de Vida , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Costos de la Atención en Salud/tendencias , Humanos , Unidades de Cuidados Intensivos/tendencias , Masculino , Persona de Mediana Edad , Admisión del Paciente/tendencias , Estudios Prospectivos , Años de Vida Ajustados por Calidad de Vida , Tasa de Supervivencia/tendencias , Sobrevivientes
3.
Eur J Intern Med ; 17(2): 96-101, 2006 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16490685

RESUMEN

BACKGROUND: A peak VO2 above 14 ml/min/kg at cardiopulmonary exercise testing and brain natriuretic peptide (BNP) levels is used to estimate survival in patients with chronic heart failure (CHF). Limited data, however, exist comparing the prognostic value of both markers simultaneously in patients with mild to moderate CHF. METHODS: We prospectively studied 85 consecutive patients (59+/-13 years, 63 men) with CHF (mean LVEF 26+/-6%). All patients underwent cardiopulmonary exercise testing with determination of peak VO2 and measurement of plasma BNP at rest. The incidence of cardiac decompensation and cardiac death was recorded in the follow-up. RESULTS: During a mean follow-up of 427+/-150 days, four deaths and ten cardiac decompensations occurred. Kaplan-Meier estimates of freedom from clinical events differed significantly for patients above and below the median BNP of 292 pg/ml and also for patients above and below a peak VO2 of 14 ml/min/kg (p<0.05 each). BNP and peak VO2 (area under the ROC 0.75 vs. 0.72) showed a comparable discrimination of CHF patients with adverse cardiac events. The prognostic information of BNP was at least as powerful as that derived from peak VO2. A BNP above 324 pg/ml was associated with a risk ratio of 8.8 for adverse cardiac events. CONCLUSIONS: In patients with mild to moderate CHF, BNP measurements appear to be an alternative to peak VO2 determined by cardiopulmonary exercise testing for the assessment of prognosis in CHF. BNP may facilitate the ambulatory management of patients with mild to moderate CHF since it is less expensive, less time-consuming, and free of procedural risk compared to exercise testing.

4.
J Am Coll Cardiol ; 41(9): 1523-8, 2003 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-12742293

RESUMEN

OBJECTIVES: We investigated whether cardiac resynchronization therapy (CRT) affects myocardial glucose metabolism and perfusion in dilated cardiomyopathy (DCM) and left bundle branch block (LBBB). BACKGROUND: Patients with DCM and LBBB present with asynchronous left ventricular (LV) activation, leading to reduced septal glucose metabolism. Cardiac resynchronization therapy recoordinates LV activation, but its effects on myocardial glucose metabolism and perfusion remain unknown. METHODS: In 15 patients (10 females; 61 +/- 13 years) with DCM and LBBB (QRS width 165 +/- 15 ms), gated (18)F-fluorodeoxyglucose (FDG) positron emission tomography (PET) and technetium-99m ((99m)Tc)-sestamibi single-photon emission computed tomography were performed before and after two weeks of CRT. Uptake of FDG and (99m)Tc-sestamibi was determined in four LV wall areas. Ejection fraction and volumes were calculated from gated PET. RESULTS: Baseline FDG uptake was heterogeneous (p < 0.0001), with lowest uptake in the septal region (56 +/- 12%) and highest uptake in the lateral region (89 +/- 6%). During CRT, septal and anterior increases (p < 0.01) and lateral decreases (p < 0.01) resulted in homogeneously distributed glucose metabolism. Baseline heterogeneity (p < 0.0001) in (99m)Tc-sestamibi uptake was modest (lowest septal 65 +/- 10%; maximum lateral 84 +/- 5%) and also reduced with CRT, although some heterogeneity (p < 0.05) remained. The septal-to-lateral ratio increased with CRT for FDG (0.62 +/- 0.12 to 0.91 +/- 0.26, p < 0.001) and (99m)Tc-sestamibi uptake (0.77 +/- 0.13 to 0.85 +/- 0.16, p < 0.01). The LV end-diastolic and end-systolic volumes decreased from 293 +/- 160 to 272 +/- 158 ml (p < 0.05) and from 244 +/- 164 to 220 +/- 160 ml (p < 0.01), respectively. Ejection fraction increased from 22 +/- 12% to 25 +/- 13% (p < 0.01). CONCLUSIONS: Glucose metabolism is reduced more than perfusion in the septal compared with LV lateral wall in patients with DCM and LBBB. Cardiac resynchronization therapy restores homogeneous myocardial glucose metabolism with less influence on perfusion.


Asunto(s)
Bloqueo de Rama/metabolismo , Bloqueo de Rama/terapia , Estimulación Cardíaca Artificial , Cardiomiopatía Dilatada/metabolismo , Cardiomiopatía Dilatada/terapia , Circulación Coronaria/fisiología , Glucosa/metabolismo , Miocardio/metabolismo , Anciano , Bloqueo de Rama/diagnóstico por imagen , Cardiomiopatía Dilatada/diagnóstico por imagen , Femenino , Atrios Cardíacos/diagnóstico por imagen , Atrios Cardíacos/metabolismo , Atrios Cardíacos/fisiopatología , Ventrículos Cardíacos/diagnóstico por imagen , Ventrículos Cardíacos/metabolismo , Ventrículos Cardíacos/fisiopatología , Hemodinámica/fisiología , Humanos , Masculino , Persona de Mediana Edad , Tomografía Computarizada de Emisión , Tomografía Computarizada de Emisión de Fotón Único
5.
J Nucl Med ; 46(8): 1256-63, 2005 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16085580

RESUMEN

UNLABELLED: The goal of this study was to validate the accuracy of the Emory Cardiac Tool Box (ECTB) in assessing left ventricular end-diastolic or end-systolic volume (EDV, ESV) and ejection fraction (LVEF) from gated (99m)Tc-methoxyisobutylisonitrile ((99m)Tc-MIBI) SPECT using cardiac MRI (cMRI) as a reference. Furthermore, software-specific characteristics of ECTB were analyzed in comparison with 4D-MSPECT and Quantitative Gated SPECT (QGS) results (all relative to cMRI). METHODS: Seventy patients with suspected or known coronary artery disease were examined using gated (99m)Tc-MIBI SPECT (8 gates/cardiac cycle) 60 min after tracer injection at rest. EDV, ESV, and LVEF were calculated from gated (99m)Tc-MIBI SPECT using ECTB, 4D-MSPECT, and QGS. Directly before or after gated SPECT, cMRI (20 gates/cardiac cycle) was performed as a reference. EDV, ESV, and LVEF were calculated using Simpson's rule. RESULTS: Correlation between results of gated (99m)Tc-MIBI SPECT and cMRI was high for EDV (R = 0.90 [ECTB], R = 0.88 [4D-MSPECT], R = 0.92 [QGS]), ESV (R = 0.94 [ECTB], R = 0.96 [4D-MSPECT], R = 0.96 [QGS]), and LVEF (R = 0.85 [ECTB], R = 0.87 [4D-MSPECT], R = 0.89 [QGS]). EDV (ECTB) did not differ significantly from cMRI, whereas 4D-MSPECT and QGS underestimated EDV significantly compared with cMRI (mean +/- SD: 131 +/- 43 mL [ECTB], 127 +/- 42 mL [4D-MSPECT], 120 +/- 38 mL [QGS], 137 +/- 36 mL [cMRI]). For ESV, only ECTB yielded values that were significantly lower than cMRI. For LVEF, ECTB and 4D-MSPECT values did not differ significantly from cMRI, whereas QGS values were significantly lower than cMRI (mean +/- SD: 62.7% +/- 13.7% [ECTB], 59.0% +/- 12.7% [4DM-SPECT], 53.2% +/- 11.5% [QGS], 60.6% +/- 13.9% [cMRI]). CONCLUSION: EDV, ESV, and LVEF as determined by ECTB, 4D-MSPECT, and QGS from gated (99m)Tc-MIBI SPECT agree over a wide range of clinically relevant values with cMRI. Nevertheless, any algorithm-inherent over- or underestimation of volumes and LVEF should be accounted for and an interchangeable use of different software packages should be avoided.


Asunto(s)
Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Imagen de Acumulación Sanguínea de Compuerta/métodos , Imagenología Tridimensional/métodos , Programas Informáticos , Volumen Sistólico , Tecnecio Tc 99m Sestamibi , Disfunción Ventricular Izquierda/diagnóstico por imagen , Adulto , Anciano , Anciano de 80 o más Años , Algoritmos , Enfermedad de la Arteria Coronaria/complicaciones , Femenino , Humanos , Aumento de la Imagen/métodos , Interpretación de Imagen Asistida por Computador/métodos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Radiofármacos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Validación de Programas de Computación , Tomografía Computarizada de Emisión de Fotón Único/métodos , Disfunción Ventricular Izquierda/etiología
6.
Chest ; 128(3): 1645-9, 2005 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16162770

RESUMEN

OBJECTIVE: Fractional flow reserve (FFR) is a valid surrogate for hemodynamic significance in stenotic native coronary arteries, but its validity in patients with coronary stent restenosis is unknown. DESIGN: Prospective. SETTING: University hospital. PATIENTS: We studied 42 patients (mean age +/- 1 SD, 62 +/- 10 years) with stent restenosis and 57 patients (mean age, 61 +/- 12 years) with a native coronary lesion. All patients demonstrated a single coronary lesion of intermediate severity (stenosis diameter, 40 to 70%). Determination of FFR and quantitative angiography of the stenosis were performed. RESULTS: Stenosis diameter was comparable in both groups (native, 52 +/- 11%; stent, 52 +/- 9%; not significant [NS]). FFR was lower in stent restenosis (0.77 +/- 0.15 vs 0.82 +/- 0.12, p < 0.05) and more often pathologic with an FFR < 0.75 (48% vs 26%, p < 0.05) compared to native coronary stenosis. However, the area under the receiver operating characteristic curve for native stenosis was 0.82 (95% confidence interval [CI], 0.71 to 0.94) and for stent restenosis was 0.84 (95% CI, 0.71 to 0.97; NS). In patients with an FFR > 0.75, there was no adverse coronary event that was related to the stented lesion in the subsequent 6 months. CONCLUSIONS: The threshold of stenosis diameter of coronary lesions for pathologic FFR measurement (FFR < 0.75) is similar for stent restenosis and native coronary stenosis. Thus, FFR measurement seems to be applicable for decision making in patients with stent restenosis.


Asunto(s)
Angioplastia Coronaria con Balón/efectos adversos , Estenosis Coronaria/fisiopatología , Stents/efectos adversos , Anciano , Presión Sanguínea , Implantación de Prótesis Vascular/efectos adversos , Angiografía Coronaria , Circulación Coronaria/fisiología , Reestenosis Coronaria/diagnóstico por imagen , Reestenosis Coronaria/etiología , Reestenosis Coronaria/fisiopatología , Estenosis Coronaria/diagnóstico por imagen , Femenino , Hemodinámica , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos
7.
Eur J Intern Med ; 16(5): 345-7, 2005 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16137548

RESUMEN

BACKGROUND: Patients with chronic heart failure (CHF) show inflammatory changes and elevated plasma levels of TNFalpha and endotoxins. However, the role of the CD14 C(-260)T polymorphism in patients with CHF is unclear. Therefore, we sought to determine whether the C=>T promoter polymorphism (position -260) of the CD 14 gene is associated with a higher risk for the development of CHF. METHODS: We studied 100 patients with CHF (mean age 62+/-3 years, LVEF 28+/-8%) and 100 healthy controls (59+/-10 years, p=NS; LVEF 60+/-4%, p<0.05). CD14 genotyping was performed using a PCR-RFLP technique. RESULTS: Among CHF patients, the frequency of the T allele was lower (38% vs. 48%, p<0.05) and the frequency of the C allele higher (62 % vs. 52 %, p<0.05) than among controls. The distribution of CD14 genotypes in healthy controls was as follows: CC 32%, CT 40%, and TT 28%. Among CHF patients, the TT genotype was significantly underrepresented compared to controls: CC 38%, CT 48%, and TT 14% (p<0.05). CONCLUSIONS: The C -260T polymorphism of CD14 seems to influence the susceptibility for the development of CHF. The T allele is less frequent among CHF patients than among controls. The TT genotype could be a new genetic protective factor against the development of CHF.

8.
Eur J Intern Med ; 16(6): 429-31, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16198903

RESUMEN

BACKGROUND: Fractional flow reserve (FFR) is a valid surrogate for hemodynamic significance in stenotic native coronary arteries. The aim of this study was to examine the value of FFR compared to stress perfusion myocardial scintigraphy (SPMS) in patients with coronary stent restenosis. METHODS: We studied 42 patients, aged 62+/-10 years, with stent restenosis 5.3+/-1.6 months after coronary stent implantation. All patients had a single coronary lesion of intermediate severity (diameter stenosis 40-70%). FFR measurement, SPMS, and quantitative angiography of the stent stenosis were performed in all patients. RESULTS: The mean percentage in stent diameter stenosis was 53+/-9%. FFR was 0.77+/-0.15. In 20 patients FFR was below 0.75. Nineteen patients had reversible perfusion defects in SPMS. FFR showed good diagnostic accuracy for the detection of reversible perfusion defects in SPMS (AUROC 0.86, 95% CI 0.74-0.98). The percentage of agreement of SPMS and FFR was 88%, with the best cutoff value of 0.75 for FFR. CONCLUSIONS: A FFR value of 0.75 is not only valid for diagnosing significant native coronary stenosis, but also for stent restenosis. Thus, FFR measurement should be taken into account when making decisions regarding patients with stent restenosis.

9.
Am Heart J ; 147(1): 60-5, 2004 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-14691420

RESUMEN

BACKGROUND: Plasma levels of brain natriuretic peptide (BNP) are increased in patients with left heart failure. In patients with severe pulmonary embolism (PE), primary right ventricular (RV) dysfunction is frequent. Little is known about BNP secretion in acute RV failure. METHODS: We prospectively studied 50 consecutive patients with confirmed PE (age range, 57 +/- 19 years; 36 men). PE was confirmed with pulmonary angiography, spiral computed tomography, or echocardiography and subsidiary analyses. On admission, echocardiography and BNP measurements were performed in all patients. RESULTS: Patients without RV dysfunction had significantly lower BNP levels than patients with RV dysfunction (55 +/- 69 pg/mL vs 340 +/- 362 pg/mL, P <.001). There was a significant correlation between RV end-diastolic diameter and BNP (r = 0.43, P <.05). BNP discriminated patients with or without RV dysfunction (area under the receiver operating characteristic curve, 0.78; 95% CI, 0.64-0.92). A BNP >90 pg/mL was associated with a risk ratio of 28.4 (95% CI, 3.22-251.12) for the diagnosis of RV dysfunction. All patients without LV systolic dysfunction who had syncope necessitating cardiopulmonary resuscitation had normal BNP levels. Patients with RV dysfunction had significantly more in-hospital complications (cardiogenic shock, inotropic therapy, mechanical ventilation). However, BNP levels were not predictive of mortality or in-hospital complications. CONCLUSIONS: BNP levels are frequently increased in patients with PE who have RV dysfunction, whereas patients without RV dysfunction show reference range BNP levels in the absence of left ventricular dysfunction. In acute PE, BNP elevation is highly predictive of RV dysfunction, but not of in-hospital complications and mortality.


Asunto(s)
Gasto Cardíaco Bajo/sangre , Péptido Natriurético Encefálico/sangre , Embolia Pulmonar/sangre , Disfunción Ventricular Derecha/sangre , Enfermedad Aguda , Biomarcadores/sangre , Gasto Cardíaco Bajo/etiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Embolia Pulmonar/complicaciones , Curva ROC , Disfunción Ventricular Derecha/etiología
10.
J Nucl Med ; 45(12): 2016-20, 2004 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15585475

RESUMEN

UNLABELLED: Gated myocardial perfusion SPECT allows assessment of left ventricular end-diastolic volume (EDV), left ventricular end-systolic volume (ESV), left ventricular stroke volume (SV), and left ventricular ejection fraction (LVEF). Acquiring images with the patient both prone and supine is an approved method of identifying and reducing artifacts. Yet prone positioning alters physiologic conditions. This study investigated how prone versus supine patient positioning during gated SPECT affects EDV, ESV, SV, LVEF, and heart rate. METHODS: Forty-eight patients scheduled for routine myocardial perfusion imaging were examined with gated (99m)Tc-sestamibi SPECT (at rest) while positioned prone and supine (consecutively, in random order). All parameters for both acquisitions were calculated using the commercially available QGS algorithm. RESULTS: Whereas EDV and SV were significantly lower (P < 0.0004) for prone acquisitions (EDV, 110.5 +/- 39.1 mL; SV, 55.9 +/- 13.3 mL) than for supine acquisitions (EDV, 116.9 +/- 36.2 mL; SV, 61.0 +/- 14.5 mL), ESV and LVEF did not differ significantly. Heart rate was significantly higher (P < 0.0001) during prone acquisitions (69.1 +/- 10.5 min(-1)) than during supine acquisitions (66.5 +/- 10.0 min(-1)). CONCLUSION: The observed position-dependent effect on EDV, SV, and heart rate might be explained by decreased arterial filling and increased sympathetic nerve activity. Hence, supine reference data should not be used to classify the results of prone acquisitions.


Asunto(s)
Imagen de Acumulación Sanguínea de Compuerta , Ventrículos Cardíacos/diagnóstico por imagen , Procesamiento de Imagen Asistido por Computador , Tecnecio Tc 99m Sestamibi , Tomografía Computarizada de Emisión de Fotón Único/métodos , Adulto , Anciano , Algoritmos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Posición Prona , Volumen Sistólico/fisiología , Posición Supina
11.
J Nucl Med ; 44(1): 33-9, 2003 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-12515874

RESUMEN

UNLABELLED: Myocardial perfusion imaging with (99m)Tc-tetrofosmin is based on the assumption of a linear correlation between myocardial blood flow (MBF) and tracer uptake. However, it is known that (99m)Tc-tetrofosmin uptake is directly related to energy-dependent transport processes, such as Na(+)/H(+) ion channel activity, as well as cellular and mitochondrial membrane potentials. Therefore, cellular alterations that affect these energy-dependent transport processes ought to influence (99m)Tc-tetrofosmin uptake independently of blood flow. Because metabolism ((18)F-FDG)-perfusion ((99m)Tc-tetrofosmin) mismatch myocardium (MPMM) reflects impaired but viable myocardium showing cellular alterations, MPMM was chosen to quantify the blood flow-independent effect of cellular alterations on (99m)Tc-tetrofosmin uptake. Therefore, we compared microsphere-equivalent MBF (MBF_micr; (15)O-water PET) and (99m)Tc-tetrofosmin uptake in MPMM and in "normal" myocardium. METHODS: Forty-two patients with severe coronary artery disease, referred for myocardial viability diagnostics, were examined using (18)F-FDG PET and (99m)Tc-tetrofosmin perfusion SPECT. Relative (18)F-FDG and (99m)Tc-tetrofosmin uptake values were calculated using 18 segments per patient. Normal myocardium and MPMM myocardium were classified using a previously validated (99m)Tc-tetrofosmin SPECT/(18)F-FDG PET score. In addition, (15)O-water PET was performed to assess kinetic-modeled MBF (MBF_kin), the water-perfusable tissue fraction (PTF), and the resulting MBF_micr (MBF_kin x PTF), which is comparable to tracer uptake values. (99m)Tc-tetrofosmin uptake and MBF_micr values were calculated for all normal and MPMM segments and averaged within their respective classifications. RESULTS: Mean relative (99m)Tc-tetrofosmin uptake was 86% +/- 1% in normal myocardium and 56% +/- 1% in MPMM, showing a significant difference (P < 0.001), as was expected from the classification. Contrary to these findings, mean MBF_micr in MPMM myocardium was 0.60 +/- 0.03 mL x min(-1) x mL(-1), which did not significantly differ from normal myocardium (0.64 +/- 0.01 mL x min(-1) x mL(-1)). All values are given as mean +/- SEM. CONCLUSION: Differences between reduced (99m)Tc-tetrofosmin uptake and the unchanged MBF_micr in MPMM myocardium suggest that the pathophysiologic basis of MPMM is not a blood flow reduction but cellular alterations that affect uptake and retention of (99m)Tc-tetrofosmin independently of blood flow. Therefore, it seems that perfusion deficits in MPMM myocardium are greatly overestimated by (99m)Tc-tetrofosmin and that it tends to give false-positive findings.


Asunto(s)
Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/fisiopatología , Miocardio/metabolismo , Compuestos Organofosforados/farmacocinética , Compuestos de Organotecnecio/farmacocinética , Isótopos de Oxígeno/farmacocinética , Tomografía Computarizada de Emisión , Agua/metabolismo , Adulto , Anciano , Enfermedad de la Arteria Coronaria/clasificación , Circulación Coronaria , Femenino , Fluorodesoxiglucosa F18/farmacocinética , Corazón/diagnóstico por imagen , Humanos , Masculino , Microesferas , Persona de Mediana Edad , Radiofármacos/farmacocinética , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Distribución Tisular , Tomografía Computarizada de Emisión de Fotón Único
12.
Am J Cardiol ; 94(9): 1129-33, 2004 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-15518606

RESUMEN

Endocardial electromechanical mapping (EEM) has been proposed as a method for myocardial viability assessment. However, the impact of EEM data on clinical outcome has not been studied before. We sought to assess the prognostic value of EEM in patients with left ventricular (LV) dysfunction undergoing percutaneous coronary intervention (PCI). Seventy-five patients with coronary artery disease and LV dysfunction (angiographic LV ejection fraction [EF] 49 +/- 15%) underwent LV EEM for myocardial viability assessment before coronary revascularization. EEM parameters included mean unipolar electrographic amplitude, mean local shortening, LV volumes, LVEF, number of regions with electrographic amplitudes <7.5 mV, number of electromechanical mismatch, and match regions. Cardiac death, nonfatal myocardial infarction, nonfatal stroke, and acute heart failure requiring hospitalization were defined as clinical events. During a follow-up of 3.6 +/- 1.8 years, 20 clinical events occurred. Event-free survival after coronary revascularization was significantly better in patients with a mean unipolar electrographic amplitude of >/=9.5 mV than in patients with a mean unipolar electrographic amplitude of <9.5 mV (88% vs 57%; p <0.005). Cox regression analysis revealed angiographic LVEF, mean electrographic amplitude, number of regions with electrographic amplitudes <7.5 mV, number of electromechanical match regions, and EEM EF as univariate predictors of clinical events. In a multivariate analysis, angiographic LVEF <40% (hazard ratio 4.78, p <0.005) and mean electrographic amplitude <9.5 mV (hazard ratio 2.92, p <0.05) were independent predictors of clinical events. Thus, EEM provides prognostic information in patients with LV dysfunction undergoing coronary revascularization.


Asunto(s)
Angioplastia Coronaria con Balón , Mapeo del Potencial de Superficie Corporal , Endocardio/fisiopatología , Endocardio/cirugía , Disfunción Ventricular Izquierda/diagnóstico , Disfunción Ventricular Izquierda/terapia , Anciano , Angiografía Coronaria , Enfermedad de la Arteria Coronaria/diagnóstico , Enfermedad de la Arteria Coronaria/terapia , Femenino , Estudios de Seguimiento , Alemania , Humanos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Valor Predictivo de las Pruebas , Pronóstico , Estadística como Asunto , Volumen Sistólico/fisiología , Análisis de Supervivencia , Factores de Tiempo , Resultado del Tratamiento
13.
IEEE Trans Med Imaging ; 21(10): 1264-70, 2002 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-12585708

RESUMEN

Region-by-region comparison of data concerning left ventricular (LV) status is difficult to perform quantitatively if the data was acquired from disparate imaging modalities. We validated a method for comparing measurements obtained by electromechanical mapping (EMM) catheter with dobutamine stress echocardiography (DSE) via biplane contrast ventriculography, with the assistance of three-dimensional (3-D) echocardiographic data. The ventriculograms were traced and the borders were used to reconstruct the LV in 3-D with the aid of a database of 3-D echocardiographic studies. The 3-D LV was oriented to the EMM data based on the body coordinates and then manually scaled and translated to fit. The EMM data were mapped to the 3-D surface. The 3-D surface was divided into the 16 regions defined for echocardiographic assessment. The mean EMM value for local linear shortening, a parameter of function, was computed in each segment. The EMM and semiquantitative echocardiographic assessments of regional myocardial function were compared by segment, and the volume of the 3-D LV was compared with the volume computed from the ventriculogram. The volume of the 3-D surface correlated closely with that of the ventriculogram (r = 0.97, SEE = 27.4 ml) but with a significant overestimation of 63 +/- 35 ml. There was a highly significant (p < 0.0001) agreement in regional function between EMM and echo. Local linear shortening correlated significantly (p < 0.0001) with echocardiographic severity of wall motion, averaging 9.5 +/- 6.5, 8.1 +/- 5.4, 5.9 +/- 4.8, and 6.2 +/- 3.3 in segments read as normal, hypokinetic, akinetic, and dyskinetic, respectively. The method presented is valid for comparing cardiac parameters derived from disparate image data on a region-by-region basis by employing anatomic landmarks on 3-D reconstructions of the LV endocardial surface.


Asunto(s)
Pruebas de Función Cardíaca/métodos , Aumento de la Imagen/métodos , Imagenología Tridimensional/métodos , Técnica de Sustracción , Disfunción Ventricular Izquierda/diagnóstico , Mapeo del Potencial de Superficie Corporal/métodos , Diagnóstico por Imagen/métodos , Ecocardiografía/métodos , Imagen de Acumulación Sanguínea de Compuerta , Humanos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Supervivencia Tisular/fisiología , Disfunción Ventricular Izquierda/patología , Disfunción Ventricular Izquierda/fisiopatología
14.
Med Klin (Munich) ; 98(3): 123-32, 2003 Mar 15.
Artículo en Alemán | MEDLINE | ID: mdl-12647086

RESUMEN

BACKGROUND AND PURPOSE: The "Therapeutic Intervention Scoring System" (TISS) and the simplified version TISS-28 obtain the therapeutic workload in the critically ill and may be used for outcome prediction. The feasibility and applicability regarding cost analysis and outcome prediction of TISS and TISS-28 have been assessed in 303 consecutive medical patients staying longer than 24 h in the intensive care unit (ICU). PATIENTS AND METHODS: The mean age of the enrolled patients was 62 +/- 12 years, 216 (71%) patients were male, length of ICU stay 3.7 +/- 4.7 days, and SAPS II (Simplified Acute Physiology Score) 26 +/- 13 points. The overall mortality was 44 patients (14.5%) with 25 patients (8.3%) dying while on the ICU. RESULTS: The data collection process for TISS took significantly longer than for TISS-28. On the day of admission, the correlation of TISS and TISS-28 was excellent (r(2) = 0.91; p < 0.001). The discriminatory power as assessed by the area under the receiver operating characteristic (ROC) curve was satisfactory for TISS (0.79 +/- 0.04), TISS-28 (0.76 +/- 0.04), and SAPS II (0.77 +/- 0.04) with regard to outcome prediction. Patient-specific costs per TISS-28 point amounted to 36 euros.--and were significantly higher than the 25 euros.--calculated per TISS point. Staff costs (42%) were the most prominent cost-generating factor, and patient-specific costs contributed two thirds to the total ICU costs. There was no association of severity of illness or number of organ failure and costs. Only the length of ICU stay correlated strongly with the costs of the individual patients during the ICU stay (r(2) = 0.79; p < 0.001). CONCLUSION: The faster data collection process as well as the uniformity of the system are strong clinical and scientific advantages of the TISS-28. In addition, TISS-28 is capable of calculating individual costs in an acceptable time frame. Therefore TISS-28 serves as a valuable tool for quality assurance and cost analysis purposes in the medical ICU.


Asunto(s)
Costos y Análisis de Costo/estadística & datos numéricos , Cuidados Críticos/economía , Enfermedad Crítica/economía , Modelos Económicos , Programas Nacionales de Salud/economía , Índice de Severidad de la Enfermedad , Anciano , Enfermedad Crítica/mortalidad , Estudios de Factibilidad , Femenino , Alemania , Humanos , Tiempo de Internación/economía , Masculino , Persona de Mediana Edad , Pronóstico , Curva ROC , Tasa de Supervivencia
15.
J Heart Lung Transplant ; 31(1): 16-26, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21959123

RESUMEN

BACKGROUND: Medical and psychosocial factors are related to 1-year outcomes in the Waiting for a New Heart Study. With increased use of mechanical circulatory support devices (MCSD) over the course of the study, we can now evaluate these variables as predictors of MCSD in an extended follow-up. METHODS: Analyses focused on 313 MCSD-free patients (82% men; aged 53 ± 11 years) newly listed for heart transplantation (HTx). Variables assessed at time of listing included psychosocial risk (depression, social isolation), quality of life, waiting list stress, and medical risk (Heart Failure Survival Score, pulmonary capillary wedge pressure). Cumulative incidence functions and cause-specific Cox models examined the association of medical and psychosocial risk (low: non-depressed and socially integrated; medium: depressed or socially isolated; high: depressed and socially isolated) with time until MCSD, considering covariates and competing outcomes (death, high-urgency transplantation [HU-HTx], elective HTx, and delisting due to clinical improvement or deterioration). RESULTS: Psychosocial risk groups were comparable regarding demographics, medical parameters, and quality of life, but differed in waiting list-related stressors. During follow-up (median, 326; range, 5-1,849 days), 26 patients received MCSD, 53 died, 144 underwent HTx (103 in HU status), and 53 were delisted (15 deteriorated, 31 improved). Non-depressed and socially integrated patients did not require MCSD. Controlling for medical risk, psychosocial risk significantly contributed to MCSD, HU-HTx, and improvement; medical risk and female gender predicted death (p < 0.05). CONCLUSIONS: Psychosocial risk at time of listing affects the prognosis of HTx candidates beyond medical risk. Psychosocial interventions may help to stabilize patients' health.


Asunto(s)
Depresión/psicología , Insuficiencia Cardíaca/cirugía , Trasplante de Corazón/psicología , Corazón Auxiliar , Evaluación de Resultado en la Atención de Salud , Psicometría/métodos , Listas de Espera , Depresión/epidemiología , Femenino , Estudios de Seguimiento , Insuficiencia Cardíaca/psicología , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Países Bajos/epidemiología , Pronóstico , Estudios Prospectivos , Medición de Riesgo , Índice de Severidad de la Enfermedad , Resultado del Tratamiento
17.
J Invasive Cardiol ; 22(7): 317-21, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20603503

RESUMEN

BACKGROUND: Patients with metabolic syndrome (MetS) are at increased risk of cardiovascular events. The long-term effectiveness of sirolimus-eluting stents (SES) in patients with MetS and in diabetic patients is not well defined. METHODS: 563 consecutive patients with 629 de novo coronary lesions (< 50 mm lesion length, reference diameter < 3.5 mm) successfully treated with SES were enrolled in the study and followed for 41 +/- 17 months. Bifurcation and left main lesions were excluded. Patients were categorized into three groups: 1) no MetS and no diabetes; 2) MetS and no diabetes; and 3) diabetes. MetS was defined as the presence of > or = 3 of the following criteria: obesity, hypertension, hypertriglyceridemia, low high-density lipoprotein cholesterol, elevated fasting glucose. RESULTS: 284 patients (51%) with 318 lesions had neither MetS nor diabetes, 148 patients (26%) with 163 lesions had MetS without diabetes and 131 patients (23%) with 148 lesions had diabetes. Baseline angiographic parameters were comparable between the three groups. Clinically driven target lesion revascularization rates for controls, MetS and diabetics were 7.7%, 5.4% and 14.5%, respectively (p = 0.041). Mortality rates for the three groups were 4.2%, 10.1% and 15.3%, respectively (p = 0.042). There were also significant differences in stent thrombosis (ST) rates with 0.3% in controls, 0.6% in MetS and 6.1% in diabetics (p = 0.037). Annual mortality and ST rates for controls, patients with MetS and diabetic patients were 1.2%, 3.0% and 5.6% (p = 0.037) and 0.2%, 0.3% and 2.7% (p = 0.039), respectively. Late loss in-lesion was 0.19 +/- 0.59 mm in controls, 0.17 +/- 0.44 mm in patients with MetS/no diabetes and 0.46 +/- 0.81 mm in diabetics (p < 0.001). CONCLUSION: During long-term follow up after implantation of SES in de novo coronary lesions, MetS without diabetes does not result in an increase in target lesion revascularization or ST rates compared with control patients. However, patients with MetS have a higher follow-up mortality rate compared to control patients.


Asunto(s)
Angioplastia Coronaria con Balón/métodos , Enfermedad Coronaria/terapia , Complicaciones de la Diabetes/complicaciones , Stents Liberadores de Fármacos , Síndrome Metabólico/complicaciones , Sirolimus , Anciano , Enfermedad Coronaria/mortalidad , Trombosis Coronaria/epidemiología , Trombosis Coronaria/prevención & control , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Pronóstico , Tasa de Supervivencia , Resultado del Tratamiento
19.
Eur J Nucl Med Mol Imaging ; 35(2): 311-8, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17922271

RESUMEN

PURPOSE: There is proven evidence for the importance of myocardial perfusion-single-photon emission computed tomography (SPECT) with computerised determination of summed stress and rest scores (SSS/SRS) for the diagnosis of coronary artery disease (CAD). SSS and SRS can thereby be calculated semi-quantitatively using a 20-segment model by comparing tracer-uptake with values from normal databases (NDB). Four severity-degrees for SSS and SRS are normally used: <4, 4-8, 9-13, and > or =14. Manufacturers' NDBs (M-NDBs) often do not fit the institutional (I) settings. Therefore, this study compared SSS and SRS obtained with the algorithms Quantitative Perfusion SPECT (QPS) and 4D-MSPECT using M-NDB and I-NDB. METHODS: I-NDBs were obtained using QPS and 4D-MSPECT from exercise stress data (450 MBq (99m)Tc-tetrofosmin, triple-head-camera, 30 s/view, 20 views/head) from 36 men with a low post-stress test CAD probability and visually normal SPECT findings. Patient group was 60 men showing the entire CAD-spectrum referred for routine perfusion-SPECT. Stress/rest results of automatic quantification of the 60 patients were compared to M-NDB and I-NDB. After reclassifying SSS/SRS into the four severity degrees, kappa values were calculated to objectify agreement. RESULTS: Mean values (vs M-NDB) were 9.4 +/- 10.3 (SSS) and 5.8 +/- 9.7 (SRS) for QPS and 8.2 +/- 8.7 (SSS) and 6.2 +/- 7.8 (SRS) for 4D-MSPECT. Thirty seven of sixty SSS classifications (kappa = 0.462) and 40/60 SRS classifications (kappa = 0.457) agreed. Compared to I-NDB, mean values were 10.2 +/- 11.6 (SSS) and 6.5 +/- 10.4 (SRS) for QPS and 9.2 +/- 9.3 (SSS) and 7.2 +/- 8.6 (SRS) for 4D-MSPECT. Forty four of sixty patients agreed in SSS and SRS (kappa = 0.621 resp. 0.58). CONCLUSION: Considerable differences between SSS/SRS obtained with QPS and 4D-MSPECT were found when using M-NDB. Even using identical patients and identical I-NDB, the algorithms still gave substantial different results.


Asunto(s)
Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Bases de Datos Factuales/normas , Imagenología Tridimensional/normas , Tomografía Computarizada de Emisión de Fotón Único/métodos , Tomografía Computarizada de Emisión de Fotón Único/normas , Adulto , Anciano , Femenino , Alemania , Humanos , Masculino , Persona de Mediana Edad , Valores de Referencia , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
20.
J Heart Lung Transplant ; 27(7): 746-52, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18582804

RESUMEN

BACKGROUND: Current treatment of advanced chronic heart failure comprises pharmacologic approaches, multidisciplinary management strategies and device therapy. We sought to compare the outcome after cardiac synchronization therapy (CRT) with the outcome after heart transplantation within a contemporary heart failure management program. METHODS: In a cohort study, survival and quality of life were assessed in 105 patients who had received CRT (53% with defibrillator) for severe heart failure and in 112 heart transplant recipients attending a heart failure clinic at a tertiary hospital. For assessment of health-related quality of life the Medical Outcome Short Form 36 (SF-36) was applied to the survivors. A propensity score for receiving transplantation vs CRT was developed using logistic regression and was incorporated into statistical models. RESULTS: Severity of heart failure before heart transplantation or CRT was similar. Survival was not different between device recipients and transplant recipients by Kaplan-Meier analysis. Cox regression analysis with time-dependent covariates revealed a significant interaction between treatment and time, which favored transplantation late after intervention. There were no significant differences in 7 of 8 subjective measures of health-related quality of life. The score for physical functioning was higher in the transplantation group; this difference remained of borderline significance after multivariate adjustment. CONCLUSIONS: Contemporary management of patients with advanced heart failure including CRT leads to improved survival and quality of life and diminishes the difference in these outcomes between conservative management and heart transplantation within the time-frame studied. Patient selection for heart transplantation requires consideration of these results.


Asunto(s)
Estimulación Cardíaca Artificial , Insuficiencia Cardíaca/terapia , Trasplante de Corazón , Marcapaso Artificial , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Calidad de Vida , Índice de Severidad de la Enfermedad , Tasa de Supervivencia , Resultado del Tratamiento
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