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1.
Eur Heart J ; 23(23): 1849-53, 2002 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-12445533

RESUMEN

INTRODUCTION: Quantitative angiographic assessment after balloon angioplasty is a poor predictor of immediate and long-term outcome. However, the measurement of blood flow velocity during angioplasty has been proved clinically useful. AIMS: To analyse the value of the maximal stenotic flow velocity and the presence of stenotic flow velocity acceleration (aSV) for the long-term outcome after balloon angioplasty. METHODS AND RESULTS: Patients undergoing single lesion angioplasty within the DEBATE trial were included. aSV was defined as acceleration in the stenotic coronary flow velocity >50% baseline velocity assessed at a reference site of the target vessel. After balloon angioplasty diameter stenosis, minimal lumen diameter (MLD) and coronary flow velocity reserve were similar between the aSV (n=54) and non-aSV group (n=125). At follow-up, the aSV group had a higher restenosis rate (52% vs 30%, P=0.006) The presence of aSV was the strongest independent predictor of restenosis (OR 3.08, 95% CI 1.35 to 7.05, P=0.008). The best predictive cut-off value of SV was 101cm.s(-1) (sensitivity of 46%, specificity of 81%, positive predictive value of 85% and a negative predictive value of 58%). CONCLUSION: Following angioplasty, SV appears to be exquisitely sensitive to the changes experienced at the treated area without depending on the status of the microcirculation.


Asunto(s)
Angioplastia de Balón/métodos , Circulación Coronaria/fisiología , Estenosis Coronaria/terapia , Velocidad del Flujo Sanguíneo/fisiología , Reestenosis Coronaria/diagnóstico , Reestenosis Coronaria/fisiopatología , Estenosis Coronaria/fisiopatología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Resultado del Tratamiento , Ultrasonografía Doppler
2.
Eur Heart J ; 23(13): 1038-44, 2002 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12093056

RESUMEN

AIMS: Intracoronary radiation is a promising therapy potentially reducing restenosis following catheter-based interventions. Currently, only limited data on this treatment are available. The feasibility and outcome in daily routine practice, however, is unknown. METHODS AND RESULTS: In 100 consecutive patients, intracoronary beta-radiation was performed with a (90)Strontium system (Novoste Beta-Cathtrade mark) following angioplasty. Predominantly complex (73% type B2 and C) and long lesions (length 24.3+/-15.3 mm) were included (37% de novo, 19% restenotic and 44% in-stent restenotic lesions). Radiation success was 100%. Mean prescribed dose was 19.8+/-2.5 Gy. A pullback procedure was performed in 19% lesions. Geographic miss occurred in 8% lesions. Periprocedural thrombus formation occurred in four lesions, dissection in nine lesions. During hospital stay, no death, acute myocardial infarction, or repeat revascularization was observed. Major adverse cardiac events occurred predominantly between 6 and 12 months after the index procedure with major adverse cardiac event-free survival of 66% at 12 months (one death, 10 Q-wave myocardial infarctions, 23 target vessel revascularizations; ranked for worst event). CONCLUSION: Routine catheter-based intracoronary beta-radiation therapy after angioplasty is safe and feasible with a high acute procedural success. The clinical 1-year follow-up showed delayed occurrence of major adverse cardiac events between 6 and 12 months after the index procedure.


Asunto(s)
Braquiterapia/métodos , Reestenosis Coronaria/radioterapia , Anciano , Angioplastia Coronaria con Balón , Partículas beta/uso terapéutico , Supervivencia sin Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Radioisótopos de Estroncio/uso terapéutico
3.
Eur Heart J ; 23(8): 641-9, 2002 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11969279

RESUMEN

AIMS: We sought to compare the effect of intracoronary beta-radiation on the vessel dimensions in de novo lesions using three-dimensional intravascular ultrasound quantification after balloon angioplasty and stenting. METHODS AND RESULTS: Forty patients (44 vessels; 28 balloon angioplasty and 16 stenting) treated with catheter-based beta-radiation and 18 non-irradiated control patients (18 vessels; 10 balloon angioplasty and 8 stenting) were investigated by means of three-dimensional volumetric intravascular ultrasound analysis post-procedure and at 6-8 months follow-up. Total vessel (EEM) volume enlarged after both balloon angioplasty and stenting (+37 mm(3) vs +42 mm(3), P=ns), but vessel wall volume (plaque plus media) also increased similarly (+33 mm(3) vs +49 mm(3), P=ns) in the irradiated patients. Lumen volume remained unchanged in both groups (+3 mm(3) vs -7 mm(3), P=ns). In the stent-covered segments, neointima at follow-up was significantly smaller in the irradiated group than the control group (8 mm(3) vs 27 mm(3), P=0.001, respectively), but the total amount of tissue growth was similar in both groups (33 mm(3) vs 29 mm(3), P=ns). CONCLUSIONS: Intracoronary beta-radiation induces vessel enlargement after balloon angioplasty and/or stenting, accommodating tissue growth. Additional stenting may not play an important role in the prevention of constrictive remodelling in the setting of catheter-based intracoronary beta-radiotherapy.


Asunto(s)
Angioplastia Coronaria con Balón , Cateterismo Cardíaco , Vasos Coronarios/cirugía , Observación , Stents , Anciano , Partículas beta , Implantación de Prótesis Vascular , Reestenosis Coronaria/etiología , Estenosis Coronaria/complicaciones , Estenosis Coronaria/terapia , Vasos Coronarios/diagnóstico por imagen , Vasos Coronarios/efectos de la radiación , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Resultado del Tratamiento , Ultrasonografía Intervencional
4.
Circulation ; 105(5): 550-3, 2002 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-11827917

RESUMEN

BACKGROUND: Radioactive stents with an activity of 0.75 to 12 microCi have shown >40% edge restenosis due to neointimal hyperplasia and negative remodeling. This trial evaluated whether radioactive Cold Ends stents might resolve edge restenosis by preventing remodeling at the injured extremities. METHODS AND RESULTS: The 25-mm long (15-mm radioactive center and 5-mm nonradioactive ends) Cold Ends stents had an activity of 3 to 12 microCi at implantation. Forty-three stents were implanted in 43 patients with de novo native coronary artery disease. Two procedural, 1 subacute, and 1 late stent thrombosis occurred. A restenosis rate of 22% was observed with a shift of the restenosis, usually occurring at the stent edges of radioactive stents, into the Cold Ends stents. The most severe restenosis occurred at the transition zone from radioactive to nonradioactive segments, a region located in dose fall-off. CONCLUSION: Cold Ends stents did not resolve edge restenosis.


Asunto(s)
Implantación de Prótesis Vascular/efectos adversos , Braquiterapia/instrumentación , Angiografía Coronaria , Enfermedad de la Arteria Coronaria/cirugía , Oclusión de Injerto Vascular/etiología , Stents/efectos adversos , Adulto , Anciano , Anciano de 80 o más Años , Angina de Pecho/etiología , Braquiterapia/métodos , Enfermedad de la Arteria Coronaria/tratamiento farmacológico , Trombosis Coronaria/etiología , Relación Dosis-Respuesta en la Radiación , Femenino , Fibrinolíticos/uso terapéutico , Estudios de Seguimiento , Oclusión de Injerto Vascular/diagnóstico , Oclusión de Injerto Vascular/prevención & control , Humanos , Masculino , Persona de Mediana Edad , Radioisótopos de Fósforo/uso terapéutico , Inhibidores de Agregación Plaquetaria/uso terapéutico , Resultado del Tratamiento
5.
Circulation ; 104(17): 2007-11, 2001 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-11673337

RESUMEN

BACKGROUND: We have previously reported a virtual absence of neointimal hyperplasia 4 months after implantation of sirolimus-eluting stents. The aim of the present investigation was to determine whether these results are sustained over a period of 1 year. METHODS AND RESULTS: Forty-five patients with de novo coronary disease were successfully treated with the implantation of a single sirolimus-eluting Bx VELOCITY stent in São Paulo, Brazil (n=30, 15 fast release [group I, GI] and 15 slow release [GII]) and Rotterdam, The Netherlands (15 slow release, GIII). Angiographic and volumetric intravascular ultrasound (IVUS) follow-up was obtained at 4 and 12 months (GI and GII) and 6 months (GIII). In-stent minimal lumen diameter and percent diameter stenosis remained essentially unchanged in all groups (at 12 months, GI and GII; at 6 months, GIII). Follow-up in-lesion minimal lumen diameter was 2.28 mm (GIII), 2.32 mm (GI), and 2.48 mm (GII). No patient approached the >/=50% diameter stenosis at 1 year by angiography or IVUS assessment, and no edge restenosis was observed. Neointimal hyperplasia, as detected by IVUS, was virtually absent at 6 months (2+/-5% obstruction volume, GIII) and at 12 months (GI=2+/-5% and GII=2+/-3%). CONCLUSIONS: This study demonstrates a sustained suppression of neointimal proliferation by sirolimus-eluting Bx VELOCITY stents 1 year after implantation.


Asunto(s)
Implantación de Prótesis Vascular/instrumentación , Enfermedad Coronaria/cirugía , Oclusión de Injerto Vascular/prevención & control , Sirolimus/administración & dosificación , Stents , Implantación de Prótesis Vascular/efectos adversos , Implantación de Prótesis Vascular/métodos , Brasil , Estudios de Cohortes , Angiografía Coronaria , Enfermedad Coronaria/diagnóstico , Enfermedad Coronaria/tratamiento farmacológico , Preparaciones de Acción Retardada/administración & dosificación , Implantes de Medicamentos/administración & dosificación , Endosonografía , Femenino , Estudios de Seguimiento , Oclusión de Injerto Vascular/etiología , Humanos , Masculino , Persona de Mediana Edad , Países Bajos , Sirolimus/efectos adversos , Stents/efectos adversos , Tasa de Supervivencia , Resultado del Tratamiento , Túnica Íntima/efectos de los fármacos , Grado de Desobstrucción Vascular/efectos de los fármacos
6.
J Am Coll Cardiol ; 38(2): 415-20, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11499732

RESUMEN

OBJECTIVES: We sought to determine the incidence and causes of geographical miss (GM) and to evaluate its impact on edge restenosis after intracoronary beta-radiation therapy. BACKGROUND: Edge restenosis is a limitation of intracoronary beta-radiation therapy. Geographical miss is the situation in which the radiation source does not fully cover the injured segment and may lead to edge restenosis. METHODS: We analyzed 175 vessels treated according to the Beta-Radiation In Europe (BRIE) study protocol. The effective irradiated segment (EIRS) and both edges were studied with quantitative coronary angiography. The edges of the EIRS that were injured constituted the GM edges. Restenosis was defined as diameter stenosis >50% at follow-up. Geographical miss was determined by simultaneous electrocardiographic-matched, side-by-side projection of the source and balloons deflated at the injury site, in identical angiographic projections surrounded by contrast. RESULTS: Geographical miss affected 41.2% of the edges and increased edge restenosis significantly compared with non-GM edges (16.3% vs. 4.3%, respectively, p = 0.004). Restenosis was increased both in the proximal (p = 0.05) and distal (p = 0.02) GM edges compared with noninjured edges. Geographical miss associated with stent injury significantly increased edge restenosis (p = 0.006), whereas GM related to balloon injury did not significantly increase edge restenosis (p = 0.35). The restenosis in the EIRS was similar between vessels with and without GM (24.3% and 21.6%, respectively, p = 0.8). CONCLUSIONS: Geographical miss is strongly associated with restenosis at the edges of the EIRS. This effect is more prominent when caused by stenting. Geographical miss does not increase restenosis in the EIRS.


Asunto(s)
Partículas beta , Braquiterapia/efectos adversos , Enfermedad Coronaria/etiología , Cardiopatías/radioterapia , Adulto , Anciano , Angioplastia Coronaria con Balón/efectos adversos , Cateterismo Cardíaco , Enfermedad Coronaria/epidemiología , Femenino , Cardiopatías/complicaciones , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Dosis de Radiación , Estudios Retrospectivos , Stents/efectos adversos
7.
Heart ; 86(2): 193-198, Aug 2001. ilus
Artículo en Inglés | Sec. Est. Saúde SP, SESSP-IDPCPROD, Sec. Est. Saúde SP | ID: biblio-1063264

RESUMEN

Objective—To study the relation between moderate coronary dissections, coronary flow velocity reserve (CFVR), and long term outcome. Methods—523 patients undergoing balloon angioplasty and sequential intracoronary Doppler measurements were examined as part of the DEBATE II trial (Doppler endpoints balloon angioplasty trial Europe). After successful balloon angioplasty, patients were randomised to stenting or no further treatment. Dissections were graded at the core laboratory by two observers and divided into four categories: none, mild (type A-B), moderate (type C), severe (types D to F). Patients with severe dissections (n = 128) or without available reference vessel CFVR (n = 139) were excluded. The remaining 256 patients were divided into two groups according to the presence (group A, n = 45) or absence (group B, n = 211) of moderate dissection. Results—Following balloon angioplasty, there was no difference in CFVR between the two groups. At 12 months follow up, a higher rate of major adverse cardiac events was observed overall in group A than in group B (10 (22%) v 23 (11%), p = 0.041). However, the risk of major adverse events was similar in the subgroups receiving balloon angioplasty (group A, 6 (19%) v group B, 16 (16%), NS). Among group A patients, the adverse events risk was greater in those randomised to stenting (odds ratios 6.603 v 1.197, p = 0.046), whereas there was no difference in risk if the group was analysed according to whether the CFVR was 2.5 after balloon angioplasty. Conclusions—Moderate dissections left untreated result in no increased risk of major adverse cardiac events. Additional stenting does not improve the long term outcome.


Asunto(s)
Angioplastia de Balón , Ecocardiografía Doppler
8.
Heart ; 86(2): 193-8, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11454840

RESUMEN

OBJECTIVE: To study the relation between moderate coronary dissections, coronary flow velocity reserve (CFVR), and long term outcome. METHODS: 523 patients undergoing balloon angioplasty and sequential intracoronary Doppler measurements were examined as part of the DEBATE II trial (Doppler endpoints balloon angioplasty trial Europe). After successful balloon angioplasty, patients were randomised to stenting or no further treatment. Dissections were graded at the core laboratory by two observers and divided into four categories: none, mild (type A-B), moderate (type C), severe (types D to F). Patients with severe dissections (n = 128) or without available reference vessel CFVR (n = 139) were excluded. The remaining 256 patients were divided into two groups according to the presence (group A, n = 45) or absence (group B, n = 211) of moderate dissection. RESULTS: Following balloon angioplasty, there was no difference in CFVR between the two groups. At 12 months follow up, a higher rate of major adverse cardiac events was observed overall in group A than in group B (10 (22%) v 23 (11%), p = 0.041). However, the risk of major adverse events was similar in the subgroups receiving balloon angioplasty (group A, 6 (19%) v group B, 16 (16%), NS). Among group A patients, the adverse events risk was greater in those randomised to stenting (odds ratios 6.603 v 1.197, p = 0.046), whereas there was no difference in risk if the group was analysed according to whether the CFVR was < 2.5 or >/= 2.5 after balloon angioplasty. CONCLUSIONS: Moderate dissections left untreated result in no increased risk of major adverse cardiac events. Additional stenting does not improve the long term outcome.


Asunto(s)
Angioplastia Coronaria con Balón/métodos , Enfermedad Coronaria/terapia , Stents , Disección Aórtica/fisiopatología , Velocidad del Flujo Sanguíneo , Enfermedad Coronaria/fisiopatología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Resultado del Tratamiento , Ultrasonografía Intervencional
9.
Eur Heart J ; 22(15): 1311-7, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11465963

RESUMEN

BACKGROUND: Edge restenosis is a major problem after radioactive stenting. The cold-end stent has a radioactive mid-segment (15.9 mm) and non-radioactive proximal and distal 5.7 mm segments. Conceptually this may negate the impact of negative vascular remodelling at the edge of the radiation. METHOD AND RESULTS: ECG-gated intravascular ultrasound with three-dimensional reconstruction was performed post-stent implantation and at the 6-month follow-up to assess restenosis within the margins of the stent and at the stent edges in 16 patients. Angiographic restenosis was witnessed in four patients, all in the proximal in-stent position. By intravascular ultrasound in-stent neointimal hyperplasia, with a >50% stented cross-sectional area, was seen in eight patients. This was witnessed proximally (n=2), distally (n=2) and in both segments (n=4). Echolucent tissue, dubbed the 'black hole' was seen as a significant component of neointimal hyperplasia in six out of the eight cases of restenosis. Neointimal hyperplasia was inhibited in the area of radiation: Delta neointimal hyperplasia=3.72 mm3 (8.6%); in-stent at the edges of radiation proximally and distally Delta neointimal hyperplasia was 7.9 mm3 (19.0%) and 11.4 mm3 (25.6%), respectively (P=0.017). At the stent edges there was no significant change in lumen volume. CONCLUSIONS: Cold-end stenting results in increased neointimal hyperplasia in in-stent non-radioactive segments.


Asunto(s)
Braquiterapia , Enfermedad Coronaria/terapia , Vasos Coronarios/patología , Stents , Túnica Íntima/patología , División Celular/efectos de la radiación , Enfermedad Coronaria/patología , Vasos Coronarios/diagnóstico por imagen , Vasos Coronarios/efectos de la radiación , Humanos , Hiperplasia/diagnóstico por imagen , Hiperplasia/prevención & control , Radioisótopos de Fósforo/uso terapéutico , Prevención Secundaria , Stents/efectos adversos , Ultrasonografía Intervencional
10.
Am Heart J ; 141(1): 124-30, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11136497

RESUMEN

BACKGROUND: Cilostazol is an antiplatelet agent that increases the intracellular concentration of cyclic adenosine monophosphate by inhibiting phosphodiesterase III; it has been shown to reduce neointimal hyperplasia in animal balloon injury models. METHODS: One hundred thirty patients who underwent elective stenting (Palmaz-Schatz stent) were randomly assigned to cilostazol treatment 200 mg/d (n = 65) or to ticlopidine treatment 200 mg/d (n = 65). Angiographic follow-up was performed at 6 months, and clinical follow-up was continued up to 1 year. RESULTS: One sudden death and one myocardial infarction resulting from subacute occlusion were observed in the ticlopidine group. Drug adverse effects were observed in 3 patients in the cilostazol group, as opposed to 6 patients in the ticlopidine group. In the intention-to-treat analysis, 56 patients (61 lesions) in the cilostazol group and 58 patients (58 lesions) in the ticlopidine group were assessed with quantitative coronary angiography. Late loss in the cilostazol group was smaller (0.58+/-0.52 mm vs. 1.09+/-0.65 mm, P<.0001) than in the ticlopidine group. The restenosis rate was lower in the cilostazol group than in the ticlopidine group (16% vs. 33%, P = .044). The target vessel revascularization rate at 1 year was 23% in the cilostazol group and 42% in the ticlopidine group (P =.03). CONCLUSIONS: The results of this study suggest that cilostazol may be a safe medication that is effective in preventing restenosis after stent implantation.


Asunto(s)
Enfermedad Coronaria/terapia , Inhibidores de Agregación Plaquetaria/uso terapéutico , Stents , Tetrazoles/uso terapéutico , Ticlopidina/uso terapéutico , Cilostazol , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Estudios Prospectivos , Recurrencia , Análisis de Regresión , Factores de Tiempo
11.
Circulation ; 103(1): 14-7, 2001 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-11136678

RESUMEN

BACKGROUND: Restenosis after conventional stenting is almost exclusively caused by neointimal hyperplasia. Beta-particle-emitting radioactive stents decrease in-stent neointimal hyperplasia at 6-month follow-up. The purpose of this study was to evaluate the 1-year outcome of (32)P radioactive stents with an initial activity of 6 to 12 microCi using serial quantitative coronary angiography and volumetric ECG-gated 3D intravascular ultrasound (IVUS). METHODS AND RESULTS: Of 40 patients undergoing initial stent implantation, 26 were event-free after the 6-month follow-up period and 22 underwent repeat catheterization and IVUS at 1 year; they comprised half of the study population. Significant luminal deterioration was observed within the stents between 6 months and 1 year, as evidenced by a decrease in the angiographic minimum lumen diameter (-0.43+/-0.56 mm; P:=0.028) and in the mean lumen diameter in the stent (-0.55+/-0. 63 mm; P:=0.001); a significant increase in in-stent neointimal hyperplasia by IVUS (18.16+/-12.59 mm(3) at 6 months to 27.75+/-11. 99 mm(3) at 1 year; P:=0.001) was also observed. Target vessel revascularization was performed in 5 patients (23%). No patient experienced late occlusion, myocardial infarction, or death. By 1 year, 21 of the initial 40 patients (65%) remained event-free. CONCLUSIONS: Neointimal proliferation is delayed rather than prevented by radioactive stent implantation. Clinical outcome 1 year after the implantation of stents with an initial activity of 6 to 12 microCi is not favorable when compared with conventional stenting.


Asunto(s)
Braquiterapia , Enfermedad Coronaria/radioterapia , Oclusión de Injerto Vascular/prevención & control , Radioisótopos de Fósforo/uso terapéutico , Stents , Adulto , Anciano , Braquiterapia/efectos adversos , Braquiterapia/instrumentación , Angiografía Coronaria , Enfermedad Coronaria/patología , Enfermedad Coronaria/cirugía , Endosonografía , Femenino , Estudios de Seguimiento , Oclusión de Injerto Vascular/diagnóstico , Oclusión de Injerto Vascular/cirugía , Humanos , Masculino , Persona de Mediana Edad , Radioisótopos de Fósforo/efectos adversos , Dosis de Radiación , Insuficiencia del Tratamiento , Resultado del Tratamiento
12.
Heart ; 85(1): 73-9, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11119468

RESUMEN

OBJECTIVE: To assess the mechanism of restenosis after balloon angioplasty. DESIGN: Prospective study. PATIENTS: 13 patients treated with balloon angioplasty. INTERVENTIONS: 111 coronary subsegments (2 mm each) were analysed after balloon angioplasty and at a six month follow up using three dimensional intravascular ultrasound (IVUS). MAIN OUTCOME MEASURES: Qualitative and quantitative IVUS analysis. Total vessel (external elastic membrane), plaque, and lumen volume were measured in each 2 mm subsegment. Delta values were calculated (follow up - postprocedure). Remodelling was defined as any (positive or negative) change in total vessel volume. RESULTS: Positive remodelling was observed in 52 subsegments while negative remodelling occurred in 44. Remodelling, plaque type, and dissection were heterogeneously distributed along the coronary segments. Plaque composition was not associated with changes in IVUS indices, whereas dissected subsegments had a greater increase in total vessel volume than those without dissection (1.7 mm(3) v -0.33 mm(3), p = 0.04). Change in total vessel volume was correlated with changes in lumen (p < 0.05, r = 0.56) and plaque volumes (p < 0.05, r = 0.64). The site with maximum lumen loss was not the same site as the minimum lumen area at follow up in the majority (n = 10) of the vessels. In the multivariate model, residual plaque burden had an influence on negative remodelling (p = 0.001, 95% confidence interval (CI) -0.391 to -0.108), whereas dissection had an effect on total vessel increase (p = 0.002, 95% CI 1.168 to 4.969). CONCLUSIONS: The mechanism of lumen renarrowing after balloon angioplasty appears to be determined by unfavourable remodelling. However, different patterns of remodelling may occur in individual injured coronary segments, which highlights the complexity and influence of local factors in the restenotic process.


Asunto(s)
Angioplastia Coronaria con Balón/efectos adversos , Enfermedad Coronaria/diagnóstico por imagen , Enfermedad Coronaria/terapia , Estudios de Cohortes , Vasos Coronarios/diagnóstico por imagen , Vasos Coronarios/lesiones , Estudios de Seguimiento , Humanos , Procesamiento de Imagen Asistido por Computador , Modelos Cardiovasculares , Análisis Multivariante , Estudios Prospectivos , Recurrencia , Análisis de Regresión , Ultrasonografía Intervencional
13.
Eur Heart J ; 21(24): 2063-70, 2000 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11102257

RESUMEN

AIMS: We investigated the influence of tensile stress on plaque growth after balloon angioplasty with and without beta-radiation therapy. METHODS AND RESULTS: Thirty-one consecutive patients successfully treated with balloon angioplasty were analysed qualitatively and quantitatively by means of an ECG-gated three-dimensional intravascular ultrasound post-procedure and at follow-up. Eighteen patients were irradiated with catheter-based beta-radiation ((90)Sr/(90)Y source) and 13 were not (control). Studied segments were divided into 2 mm subsegments. Thus 184 irradiated and 111 non-irradiated subsegments were included. Tensile stress was calculated according to Laplace's law. The radiation dose was calculated by means of dose-volume histograms. Plaque growth was positively correlated to tensile stress in both the radiation and control groups (r=0.374, P=0.0001 and r=0.305, P=0.001). Low-dose subsegments (<6 Gy) had a significant correlation (r=0.410, P=0.0001) whereas no correlation was observed in the effective-dose subsegments (> or = 6 Gy). Multivariate analysis identified tensile stress as the only independent predictor of plaque increase in non-irradiated subsegments, whereas actual dose and plaque morphology were stronger predictors in irradiated subsegments. CONCLUSION: The results of this study suggest that plaque growth is related to tensile stress after balloon angioplasty. Intracoronary brachytherapy may alter the biophysical process on plaque growth when the prescribed dose is effectively delivered.


Asunto(s)
Angioplastia Coronaria con Balón , Braquiterapia , Enfermedad de la Arteria Coronaria/terapia , Resistencia a la Tracción , Anciano , Partículas beta , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/patología , Enfermedad de la Arteria Coronaria/radioterapia , Relación Dosis-Respuesta en la Radiación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Ultrasonografía Intervencional
14.
Jpn Circ J ; 64(10): 802-4, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11059626

RESUMEN

Septal perforator arteries play an important role in the blood supply of the anterior interventricular septum. Their intramyocardial course makes them inaccessible for coronary bypass revascularization. Although modern catheter-based techniques might be superior to coronary bypass grafting in offering the most complete revascularization in selected patient populations, a systematic review of the literature revealed a paucity of data regarding the outcome of these patients. The present report describes coronary stent implantation in a dominant septal perforator artery and the analysis of the anatomic relationship between the stent and the intraventricular septum using a new imaging technique, catheter-based intracardiac ultrasound.


Asunto(s)
Vasos Coronarios , Stents , Arterias , Ecocardiografía/métodos , Tabiques Cardíacos , Humanos , Masculino , Persona de Mediana Edad
15.
J Am Coll Cardiol ; 36(5): 1536-41, 2000 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-11079655

RESUMEN

OBJECTIVES: The aims of the study were to determine the incidence of relocation of the minimal luminal diameter (MLD) after beta-radiation therapy following balloon angioplasty (BA) and to describe a new methodological approach to define the effect of brachytherapy on treated coronary stenoses. BACKGROUND: Luminal diameter of coronary lesions may increase over time following angioplasty and irradiation. As a result, the MLD at follow-up may be relocated from its location preintervention, which may induce misleading results when a restricted definition of the target segment by quantitative coronary angiography (QCA) is performed. METHODS: Patients treated with BA followed by intracoronary brachytherapy according to the Dose-Finding Study constituted the study population. A historical cohort of patients treated with BA was used as control group. To be included in the analysis, an accurate angiographic documentation of all instrumentations during the procedure was mandatory. In the irradiated patients, four regions were defined by QCA: vessel segment (VS), target segment (TS), injured segment (INS), and irradiated segment (IRS). RESULTS: Sixty-five patients from the Dose-Finding Study and 179 control patients were included. At follow-up, MLD was relocated more often in the radiation group (78.5% vs. 26.3%; p < 0.0001). The rate of >50% diameter stenosis differed among the four predefined regions: 3.1% in the TS; 7.7% in the INS; 9.2% in the IRS and 13.8% in the VS. CONCLUSIONS: Relocation of the MLD is commonly demonstrated after BA and brachytherapy, and it should be taken into account during the analysis of the results of radiation clinical trials.


Asunto(s)
Enfermedad Coronaria/patología , Enfermedad Coronaria/radioterapia , Angioplastia de Balón , Cardiología/métodos , Enfermedad Coronaria/terapia , Femenino , Humanos , Masculino , Persona de Mediana Edad
16.
Circulation ; 102(12): 1434-9, 2000 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-10993864

RESUMEN

BACKGROUND: Recent reports demonstrate that intracoronary radiation affects not only neointimal formation but also vascular remodeling. Radioactive stents and catheter-based techniques deliver radiation in different ways, suggesting that different patterns of remodeling after each technique may be expected. METHODS AND RESULTS: We analyzed remodeling in 18 patients after conventional stent implantation, 16 patients after low-activity radioactive stent implantation, 16 patients after higher activity radioactive stent implantation, and, finally, 17 patients who underwent catheter-based radiation followed by conventional stent implantation. Intravascular ultrasound with 3D reconstruction was used after stent implantation and at the 6-month follow-up to assess remodeling within the stent margins and at its edges. Preprocedural characteristics were similar between groups. In-stent neointimal hyperplasia (NIH) was inhibited by high-activity radioactive stent implantation (NIH 9.0 mm(3)) and by catheter-based radiation followed by conventional stent implantation (NIH 6.9 mm(3)) compared with low-activity radioactive stent implantation (NIH 21.2 mm(3)) and conventional stent implantation (NIH 20.8 mm(3)) (P:=0.008). No difference in plaque or total vessel volume was seen behind the stent in the conventional, low-activity, or high-activity stent implantation groups. However, significant increases in plaque behind the stent (15%) and in total vessel volume (8%) were seen in the group that underwent catheter-based radiation followed by conventional stent implantation. All 4 groups demonstrated significant late lumen loss at the stent edges; however, edge restenosis was seen only in the group subjected to high-activity stent implantation and appeared to be due to an increase in plaque and, to a lesser degree, to negative remodeling. CONCLUSIONS: Distinct differences in the patterns of remodeling exist between conventional, radioactive, and catheter-based radiotherapy with stenting.


Asunto(s)
Enfermedad Coronaria/terapia , Stents , Túnica Íntima/patología , Adulto , Anciano , Enfermedad Coronaria/patología , Enfermedad Coronaria/radioterapia , Femenino , Estudios de Seguimiento , Humanos , Hiperplasia/prevención & control , Hiperplasia/radioterapia , Masculino , Persona de Mediana Edad , Dosificación Radioterapéutica , Recurrencia , Estudios Retrospectivos , Túnica Íntima/efectos de la radiación
17.
Circulation ; 102(13): 1484-9, 2000 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-11004137

RESUMEN

BACKGROUND: The "edge effect," late lumen loss at the margins of the treated segment, has become an important issue in the field of coronary brachytherapy. The aim of the present study was to assess the edge effect in noninjured margins adjacent to the irradiated segments after catheter-based intracoronary beta-irradiation. METHODS AND RESULTS: Fifty-three vessels were assessed by means of 3-dimensional intravascular ultrasound after the procedure and at 6- to 8-month follow-up. Fourteen vessels (placebo group) did not receive radiation (sham source), whereas 39 vessels were irradiated. In the irradiated group, 48 edges (5 mm in length) were identified as noninjured, whereas 18 noninjured edges were selected in the placebo group. We compared the volumetric intravascular ultrasound measurements of the noninjured edges of the irradiated vessels with the fully irradiated nonstented segments (IRS, n=27) (26-mm segments received the prescribed 100% isodose) and the noninjured edges of the vessels of the placebo patients. The lumen decreased (6 mm(3)) in the noninjured edges of the irradiated vessels at follow-up (P:=0. 001). We observed a similar increase in plaque volume in all segments: noninjured edges of the irradiated group (19.6%), noninjured edges of the placebo group (21.5%), and IRS (21.0%). The total vessel volume increased in the IRS in the 3 groups. No edge segment was subject to repeat revascularization. CONCLUSIONS: The edge effect occurs in the noninjured margins of radiation source train in both irradiated and placebo patients. Thus, low-dose radiation may not play an important role in this phenomenon, whereas nonmeasurable device injury may be considered a plausible alternative explanation.


Asunto(s)
Angioplastia de Balón , Braquiterapia/métodos , Vasos Coronarios/diagnóstico por imagen , Vasos Coronarios/efectos de la radiación , Partículas beta , Angiografía Coronaria , Relación Dosis-Respuesta en la Radiación , Humanos , Ultrasonografía
18.
J Cardiol ; 36(1): 49-57, 2000 Jul.
Artículo en Japonés | MEDLINE | ID: mdl-10929266

RESUMEN

A 78-year-old woman with renal cell carcinoma and pulmonary metastasis presented with reversible cardiomyopathy induced by gamma(gamma)-interferon. She was treated with gamma-interferon twice a week since November 1996. She presented with severe acute congestive heart failure and gamma-interferon was immediately discontinued in December 1997. Left ventricular fractional shortening was 38% before admission, 12% on admission, and improved to 31% by 40 days after discontinuation of interferon together with administration of diuretics and angiotensin converting enzyme inhibitor. We restarted the same gamma-interferon regimen because it was effective against renal cell carcinoma after 47 days. She has remained well with no significant changes of cardiac function or renal cell carcinoma for almost one year.


Asunto(s)
Carcinoma de Células Renales/terapia , Cardiomiopatías/etiología , Interferón gamma/efectos adversos , Neoplasias Renales/terapia , Anciano , Carcinoma de Células Renales/patología , Carcinoma de Células Renales/secundario , Femenino , Humanos , Neoplasias Renales/patología , Neoplasias Pulmonares/secundario , Proteínas Recombinantes
19.
Am J Cardiol ; 85(2): 135-9, 2000 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-10955366

RESUMEN

Currently, several different designs of coronary stents are available. However, only a few of the new generation stents have been investigated in large randomized trials. Mechanical behavior of first-generation stents (Palmaz-Schatz, Gianturco-Roubin) may not be applied to the new designs. We investigated the chronic mechanical behavior (recoil) of 2 stents recently approved by the Food and Drug Administration (MULTILINK and NIR). Forty-eight patients with single-stent implantation (23 MULTILINK and 25 NIR) were assessed by means of volumetric 3-dimensional intravascular ultrasound analysis after the procedure and at 6-month follow-up. In addition, volumetric assessment of neointimal formation was performed. No significant chronic stent recoil was detected in both groups (delta MULTILINK stent volume: +5.6+/-41 mm3 [p = NS] and delta NIR stent volume + 2.1+/-26 mm3 [p = NS]). A similar degree of neointimal formation at 6 months was observed between the 2 stents (MULTILINK 46+/-31.9 mm3 vs NIR 39.9+/-27.6 mm3, p = NS). In conclusion, these 2 second-generation tubular stents did not show chronic recoil and appeared to promote similar proliferative response after implantation in human coronary arteries.


Asunto(s)
Stents , Túnica Íntima/citología , Túnica Íntima/diagnóstico por imagen , División Celular , Diseño de Equipo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Ultrasonografía
20.
Am J Cardiol ; 86(4): 375-8, 2000 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-10946027

RESUMEN

Limited data are available regarding the angiographic healing rate and physiologic impact of coronary artery dissections. Therefore, we studied the impact of coronary dissections on coronary flow velocity and outcome as well as their healing rate at 6-month follow-up balloon angioplasty. Of 297 patients who underwent balloon angioplasty, 225 underwent intracoronary Doppler measurements and 184 had Doppler and angiographic assessment at 6-month follow-up. Dissections were scored by an independent core lab (Cardialysis BV) and divided in 4 groups: mild (types A to B), moderate (type C), severe (D to F), and patients without dissections. Severe dissections (types D to F) were excluded from the analysis. Clinical, angiographic, and Doppler data were compared among the remaining 3 patient groups. From the 67 dissections detected after balloon angioplasty, only 3 (4.5%) remained unhealed at follow-up. Immediately after balloon angioplasty, the moderate dissection group was associated with a lower coronary flow velocity reserve than the patients with mild (2.16 +/- 0.60 vs 2.82 +/- 1.00, p = 0.037) or no dissections (2.16 +/- 0.60 vs 2.71 +/- 0.88, p = 0.046), respectively. In addition, higher recurrence of angina at 30 days was observed in the moderate group rather than in the mild group (5 [50%] vs 8 [16%], p = 0.0160) and in the patients without dissections (11 [12%], p = 0.007). After standard balloon angioplasty, the occurrence of unhealed dissections is a rare phenomenon. An impaired coronary flow reserve was observed after the development of nonocclusive type C dissections, which was associated with a worse short-term outcome.


Asunto(s)
Angioplastia Coronaria con Balón/efectos adversos , Circulación Coronaria , Enfermedad Coronaria/terapia , Vasos Coronarios/lesiones , Velocidad del Flujo Sanguíneo , Angiografía Coronaria , Enfermedad Coronaria/fisiopatología , Vasos Coronarios/diagnóstico por imagen , Vasos Coronarios/fisiopatología , Ecocardiografía Doppler , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Resultado del Tratamiento , Cicatrización de Heridas
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