PubMed Health⌕ Search

Biomedical subjects

Augusto D Pichard

Publications and source records attributed to Augusto D Pichard.

At least 19 recordsLinked to original sources
PubMed2003

Volumetric intravascular ultrasound evidence that distal embolization during acute infarct intervention contributes to inadequate myocardial perfusion grade.

We studied 35 consecutive patients with myocardial infarction (MI) who were treated with direct infarct percutaneous coronary intervention (PCI) using standard angiographic (complete assessment of flow grade and blush grade) and pre- and post-PCI volumetric intravascular ultrasound analysis. Plaque reduction, which is evidence of distal embolization, contributes to inadequate tissue reperfusion in this lesion setting and supports the use of distal protection in the setting of an acute MI.

Aged↗
PubMed2003

Repeat intracoronary radiation for recurrent in-stent restenosis in patients who failed intracoronary radiation.

BACKGROUND: Intracoronary radiation therapy (IRT) is the only proven treatment for in-stent restenosis (ISR). It is, however, associated with a significant failure rate. The present study evaluated the outcomes of patients who underwent repeat intracoronary radiation for recurrent ISR. METHODS AND RESULTS: Fifty-one consecutive patients who failed a previous radiation treatment, presented with angina and angiographic evidence of ISR, and were treated with percutaneous coronary intervention (PCI) and repeat radiation to the same segment were studied. Twenty-five patients were treated with gamma radiation in a dose of 15 Gy, and 26 were treated with beta radiation doses of 18.3 to 23 Gy. The mean cumulative dose for this cohort was 39.5+/-11.9 Gy (range, 29 to 75.6 Gy). The outcomes of those patients were compared with outcomes of 299 patients who also failed initial radiation but were treated with repeat conventional PCI to a previously irradiated segment without repeat radiation. At 9 months after treatment, the repeat-IRT group had lower rates of target lesion revascularization (23.5% versus 54.6%; P<0.001) and major adverse cardiac events, including target vessel revascularization (29.4% versus 61.3%; P<0.001). At 9 months, patients with repeat IRT were free of angiographic and clinical events related to the radiation therapy. CONCLUSIONS: Repeat gamma or beta radiation to treat failed IRT for ISR after conventional PCI is safe and effective at 9 months and should be considered as a therapeutic option for this difficult patient subset.

Angina Pectoris↗
PubMed2003

Predictors of subacute stent thrombosis: results of a systematic intravascular ultrasound study.

BACKGROUND: Factors leading to subacute stent thrombosis after percutaneous coronary intervention (PCI) have not been well established. We assessed the pre- and post-PCI intravascular ultrasound (IVUS) characteristics of subacute stent thrombosis. METHODS AND RESULTS: We analyzed 7484 consecutive patients without acute myocardial infarction who were treated with PCI and stenting and underwent IVUS imaging during the intervention. Twenty-seven (0.4%) had angiographically documented subacute closure <1 week after PCI (median time to subacute closure, 24 hours). Subacute closure lesions were compared with a control group (selected to be 3 times the abrupt closer group) matched by procedure date (within 6 months), age, gender, stable or unstable angina, lesion location, and additional treatment (balloon angioplasty or atherectomy). Postintervention IVUS did not identify a cause in 22% and did identify at least 1 cause for abrupt closure in 78% of patients (versus 33% in matched lesions, P=0.0002). In 48% of the patients, there were multiple causes in 48% (versus 3% in matched lesions, P<0.0001). Causes included dissection (17%), thrombus (4%), and tissue protrusion within the stent struts leading to lumen compromise lumen (4%). A total of 83% of patients with >1 of these abnormal morphologies also had reduced lumen dimensions post-PCI (final lumen <80% reference lumen). Preprocedural lesion characteristics were not different from matched lesions. CONCLUSIONS: Subacute stent thrombosis is infrequently related to the preintervention lesion characteristics. Inadequate postprocedure lumen dimensions, alone or in combination with other procedurally related abnormal lesion morphologies (dissection, thrombus, or tissue prolapse), contribute to this phenomenon.

Angioplasty, Balloon, Coronary↗
PubMed2003

Intravascular ultrasound analysis of infarct-related and non-infarct-related arteries in patients who presented with an acute myocardial infarction.

BACKGROUND: Previous studies have reported diffuse destabilization of atherosclerotic plaques in acute myocardial infarction (AMI). METHODS AND RESULTS: We used intravascular ultrasound (IVUS) to assess 78 coronary arteries (38 infarct-related arteries [IRAs] with culprit and nonculprit lesions and 40 non-IRAs) from 38 consecutive AMI patients. IVUS analysis included qualitative and quantitative measurements of reference and lesion external elastic membrane (EEM), lumen, and plaque plus media (P&M) area. Positive remodeling was defined as lesion/mean reference EEM >1.0. Culprit lesions were identified by a combination of ECG, wall motion abnormalities (ventriculogram or echocardiogram), scintigraphic perfusion defects, and coronary angiogram. Culprit lesions contained more thrombus (23.7% versus 3.4% in nonculprit IRA plaques and 3.1% in non-IRA plaques; P=0.0011). Culprit lesions were predominantly hypoechoic (63.2% versus 37.9% of nonculprit IRA plaques and 28.1% of non-IRA plaques; P=0.0022). Culprit lesions were longer (17.5+/-10.1, 9.8+/-4.0, and 10.3+/-5.7 mm, respectively; P<0.0001), had larger EEM area (15.0+/-6.0, 11.5+/-5.7, and 12.6+/-5.6 mm2, respectively; P=0.0353) and P&M area (13.0+/-6.0, 7.5+/-3.7, 9.3+/-4.3 mm2, respectively; P<0.0001), smaller lumens (2.0+/-0.9, 4.1+/-3.1, and 3.4+/-2.5 mm2, respectively; P=0.0009), and more positive remodeling (79.4%, 59.0%, and 50.8%, respectively; P=0.0155). The frequency of plaque rupture/dissection was greater in culprit, nonculprit IRA, and non-IRA plaques in AMI patients than in a control group of chronic stable angina patients with multivessel IVUS imaging. CONCLUSIONS: Culprit plaques have more markers of instability (thrombus, positive remodeling, and large plaque mass); however, these markers of instability are not typically found elsewhere. This suggests that the vascular event in AMI patients is determined by local pre-event lesion morphologies.

Angina Pectoris↗
PubMed2003

Intracoronary radiation therapy improves the clinical and angiographic outcomes of diffuse in-stent restenotic lesions: results of the Washington Radiation for In-Stent Restenosis Trial for Long Lesions (Long WRIST) Studies.

BACKGROUND: The Washington Radiation for In-Stent Restenosis Trial for long lesions (Long WRIST) was designed to determine the safety and efficacy of vascular brachytherapy for the treatment of diffuse in-stent restenosis. METHODS AND RESULTS: A total of 120 patients with diffuse in-stent restenosis in native coronary arteries (lesion length, 36 to 80 mm) were randomized for either radiation with 192Ir with 15 Gy at 2 mm from the source axis or placebo. After enrollment, 120 additional patients with the same inclusion criteria were treated with 192Ir with 18 Gy and included in the Long WRIST High Dose registry. Antiplatelet therapy was initially prescribed for 1 month and was extended to 6 months in the last 60 patients of the Long WRIST High Dose registry. At 6 months, the binary angiographic restenosis rate was 73%, 45%, and 38% in the placebo, 15 Gy, and 18 Gy radiated groups, respectively (P<0.05). At 1 year, the primary clinical end point of major cardiac events was 63% in the placebo group and 42% in the radiated group with 15 Gy (P<0.05). The major cardiac event rate was further reduced with 18 Gy (22%; P<0.05 versus 15 Gy). Late thrombosis was 12%, 15%, and 9% in the placebo group, 15 Gy group with 1 month of antiplatelet therapy, and 18 Gy group with 6 months of antiplatelet therapy, respectively. CONCLUSIONS: Vascular brachytherapy with 192Ir is safe and reduces the rate of recurrent restenosis in diffuse in-stent restenosis. The efficacy of vascular brachytherapy on angiographic and clinical outcomes is enhanced with a radiation dose of 18 Gy and prolonged antiplatelet therapy.

Brachytherapy↗
PubMed2003

The outcome of percutaneous coronary intervention in patients with in-stent restenosis who failed intracoronary radiation therapy.

OBJECTIVES: This study reports the outcome of patients who failed intracoronary radiation therapy (IRT) for the treatment of in-stent restenosis (ISR). BACKGROUND: Intracoronary radiation therapy has demonstrated a reduction in the recurrence rate of restenosis for patients with ISR. However, 10% to 30% of these patients require repeat intervention to the irradiated site. METHODS: Of 961 patients who were assigned to gamma or beta radiation for the treatment of diffuse ISR, we evaluated the outcome of 282 (29%) consecutive patients who failed IRT and compared them with the 679 (71%) patients who had successful IRT. For patients who failed radiation, the mean time to the first target vessel revascularization (TVR) was 173 +/- 127 days after the index procedure and the total duration of follow-up was 494 +/- 304 days. RESULTS: Patients who failed IRT were younger (60 +/- 10 vs. 63 +/- 11 years, p = 0.002) and had a higher incidence of restenting (51% vs. 41%, p = 0.003). The majority (55%) of the restenotic lesions after IRT failure were focal (< or =10 mm), with a mean lesion length of 11.9 +/- 1.9 mm. Of the 257 patients who had subsequent TVR after failed IRT, 68 (26%) underwent coronary artery bypass grafting and 189 (74%) underwent percutaneous coronary intervention using balloon in 61%, restenting in 26%, atheroablation in 11%, and the cutting balloon in 2% of cases. At six months, 6% of patients died, 1% had Q-wave MI, 17% had repeat TVR, and the overall rate of major adverse cardiac events was 21%. CONCLUSIONS: The predominant angiographic pattern of lesions in patients who failed IRT is focal restenosis, with these lesions responding well to conventional revascularization methods.

Aged↗
PubMed2003

Comparison of intracoronary gamma radiation for in-stent restenosis in saphenous vein grafts versus native coronary arteries.

Intracoronary gamma radiation is effective in reducing recurrent in-stent restenosis (ISR) involving native coronary arteries. This study compares the effectiveness and safety of intracoronary gamma radiation for the treatment of ISR in saphenous vein grafts (SVGs) versus native coronary arteries. In the Washington Radiation for In-Stent restenosis Trial (WRIST) series of gamma radiation trials, 1,142 patients with ISR (230 in SVG and 912 in native coronary arteries) completed 6-month clinical follow-up. All patients underwent balloon angioplasty, atherectomy, and/or restenting. Different ribbon lengths containing 6 to 23 seeds of iridium-192 were used to cover lesion lengths <80 mm. The prescribed radiation doses were 14 or 15 Gy at 2-mm radial distance from the center of the source. Baseline demographics showed that patients with SVGs were older (65 +/- 13 vs 61 +/- 11 years, p <0.001), more likely male (79% vs 64%, p <0.001), had more multivessel coronary disease (81% vs 50%, p <0.001), and less diffuse lesions (17 +/- 10 vs 24 +/- 12 mm, p <0.001). At 6 months, event-free survival was similar for patients with SVG ISR and native coronary ISR (82% vs 84%, p = 0.35). The SVG ISR population had a low rate of late total occlusion (4.6%) and late thrombosis (3.5%). Thus, treatment of ISR with gamma radiation in SVGs had similar outcome to native coronary arteries. The use of gamma radiation for the treatment of ISR should expand to SVGs.

Aged↗
PubMed2003

Impact of intracoronary radiation on in-stent restenosis involving ostial lesions.

The aim of this study was to compare 6-month clinical outcomes of patients with in-stent restenosis (ISR) involving the ostium treated with intracoronary radiation therapy (IRT) compared to placebo therapy, and also to nonostial lesions treated with IRT. Coronary interventions in ostial lesions have a high rate of recurrence of restenosis. The impact of IRT on ostial ISR has been inadequately characterized. We assessed patients enrolled in gamma (192-iridium) and beta (90-yttrium, 32-phosphorus) radiation trials for ISR at the Washington Hospital Center. Of patients receiving IRT, 105 (8%) patients had ostial ISR and 1,289 (92%) patients had nonostial ISR. Twenty-seven patients had ostial ISR and received placebo therapy. Baseline demographic and angiographic and procedural details were similar, except ostial IRT patients had a trend toward shorter lesions (15.4 +/- 10.8 vs. 24.1 +/- 12.2 mm; P < 0.001) and had a higher rate of saphenous vein graft disease (46% vs. 19%; P < 0.001) compared to nonostial IRT patients. At 6 months, ostial lesions treated with IRT for ISR had a reduced rate of target lesion revascularization (TLR) compared to ostial lesions treated with placebo (15% vs. 43%; P = 0.004). Outcomes at 6 months were similar for the ostial and nonostial IRT groups including TLR (15% vs. 14%; P = 0.80) and composite major adverse cardiac events (18% vs. 15%; P = 0.46). Intracoronary radiation therapy is effective for ostial in-stent restenotic lesions and should be comfortably used for this challenging anatomic location.

Aged↗
PubMed2003

Use of restenting should be minimized with intracoronary radiation therapy for in-stent restenosis.

Restenting at the time of intracoronary radiation therapy (IRT) for in-stent restenosis (ISR) potentially increases the risk of late total occlusion (LTO) of the treated vessel. Prolonged antiplatelet therapy with clopidogrel (6 months) has been shown to be effective in reducing LTO risk. The purpose of this study was to assess the impact of restenting on clinical outcomes following IRT for ISR with 6 months of clopidogrel. We retrospectively evaluated 1,275 patients with 6-months clinical follow-up who were enrolled in radiation trials for ISR using gamma- and beta-emitters conducted at Washington Hospital Center. Patients were analyzed according to whether additional stents were deployed at the time of IRT. The predominant indication for restenting was to optimize the final angiographic result in the event of tissue prolapse or to cover edge dissections. All patients received a minimum of 6 months of clopidogrel. Baseline clinical and angiographic characteristics were similar between the restented and nonrestented groups. Radiation was delivered successfully in all cases. At 6 months, patients treated with additional stents and IRT had a significantly higher rate of target vessel revascularization than patients without additional stents (24.6% vs. 18.7%; P = 0.011). Restenting caused more frequent late thrombosis, late total occlusion, and Q-wave myocardial infarction than no restenting (4.0% vs. 2.2%, P = 0.09; 6.1% vs. 4.3%, P = 0.14; and 1.9% vs. 0.4%, P = 0.009, respectively). Restenting for the treatment of ISR is associated with increased adverse events and should be avoided after intracoronary radiation therapy for in-stent restenosis, as restenting results in a higher recurrence rate and the potential for increased late total occlusion.

Brachytherapy↗
PubMed2003

Percutaneous interventions in radial artery grafts: clinical and angiographic outcomes.

In the modern era, radial artery graft is being used with increasing frequency to replace saphenous vein as a conduit for coronary artery bypass surgery. Several reports have shown encouraging early results of radial grafts compared to saphenous grafts. Despite these advantages, radial artery graft failure requiring revascularization does occur. We report on the clinical, angiographic, and technical characteristics and the follow-up results of 22 patients who underwent percutaneous intervention of radial grafts.

Adrenergic beta-Antagonists↗
PubMed2003

Percutaneous coronary intervention-associated nephropathy foreshadows increased risk of late adverse events in patients with normal baseline serum creatinine.

In patients with chronic renal insufficiency, further decline in renal function (DRF) after percutaneous coronary intervention (PCI) is accompanied not only by adverse in-hospital events but also by increased risk of mortality and myocardial infarction at 1 year. This analysis was undertaken to determine if patients with normal renal function who develop DRF after PCI have a comparable increase in risk of death and myocardial infarction at 1 year, and whether this risk is independent of in-hospital complications (death, myocardial infarction, urgent coronary artery bypass grafting). We performed a retrospective analysis of all patients from a single center who underwent successful PCI with no major in-hospital complications who had pre-PCI serum creatinine (SCr) </= 1.2 mg/dl and no history of renal insufficiency. One-year follow-up was obtained by mail or telephone. There were 5,967 consecutive patients who met the inclusion criteria. Of these, 208 (3.5%) developed DRF (an increase in SCr >/= 50% of baseline). They were more likely to be older, female, non-Caucasian, diabetic and/or hypertensive. They reported more prior cerebral or peripheral vascular events. They had undergone more complex PCI and were exposed to more radiographic contrast than the 96.5% who did not develop DRF. After adjustment for baseline variables, DRF remained an independent predictor of 1-year mortality, myocardial infarction, and target vessel revascularization. In patients without prior renal impairment, DRF post-PCI is rare but is associated with an increased risk of late adverse cardiac events similar to that in chronic renal insufficiency patients.

Acute Kidney Injury↗
PubMed2003

Clinical outcomes following stent implantation in internal mammary artery grafts.

We evaluated our experience with percutaneous coronary intervention (PCI) of internal mammary artery (IMA) grafts. From the institution's database we identified 288 patients with 311 IMA lesions. Of these, 82 (26.4%) had stents placed during PCI. Angiographic success was 92%. Mortality at 1 month was 1.7%, myocardial infarction (MI) 15.7%, and target lesion revascularization (TLR) 0.4%. Cumulative 1-year event rates were mortality 6.4%, MI 20.4%, and TLR 8.0%. TLR rates were significantly higher in the stented lesions than lesions treated with angioplasty alone (19.2% vs. 4.9%; P = 0.004). The higher TLR rate in stented lesions was most apparent at the anastomotic site (25.0% vs. 4.2%; P = 0.006). Percutaneous revascularization of IMA grafts can be performed safely with high procedural success and excellent short- and long-term results. Stenting, particularly at the anastomotic site, was associated with significantly greater rates of TLR than angioplasty alone.

Aged↗
PubMed2003

Additional stenting promotes intimal proliferation and compromises the results of intravascular radiation therapy: an intravascular ultrasound study.

BACKGROUND: Vascular brachytherapy (VBT) reduces in-stent restenosis (ISR). However, additional stenting at the time of radiation may be associated with a worse outcome. METHODS AND RESULTS: Intravascular ultrasound (IVUS) was performed after VBT and at 6 months follow-up in 79 native artery ISR patients treated with gamma-radiation who participated in the Washington Radiation for In-Stent restenosis Trial (WRIST), Gamma-1, and Angiorad Radiation Technology for In-Stent restenosis Trial in Coronaries (ARTISTIC) trials. Patients were treated with (192)Ir at 14 or 15 Gy at 2 mm from the source. Additional stents were used to treat the ISR lesions in 45 patients; these patients were then compared with the 34 patients treated without restenting. Paired measurements included stent, lumen, and intimal hyperplasia volumes. After the VBT procedure, intimal hyperplasia volume was smaller in the group treated with additional stents (54 +/- 33 mm(3) vs 34 +/- 33 mm(3), P =.012), but minimal lumen area was similar between the 2 groups (4.3 +/- 1.5 mm(2) vs 4.7 +/- 1.4 mm(2) respectively, P = NS). Between the time of the VBT procedure and follow-up, intimal hyperplasia volume increased by 27 +/- 19 mm(3) in the restented group and by 9 +/- 21 mm(3) in the group treated without additional stents (P =.014). At 6 months, intimal volume was similar in the 2 groups, but minimal lumen area was slightly smaller in the group treated with additional stents (3.4 +/- 1.8 mm(2) vs 4.2 +/- 1.7 mm(2), P =.053). Patients treated with additional stents had more target lesion revascularizations than the group treated without additional stents (38% vs 15%, P =.02). CONCLUSIONS: Additional stenting reduces intimal hyperplasia within the stents acutely. However, it compromises the benefit of VBT by promoting higher intimal regrowth within months after radiation.

Brachytherapy↗