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Roxana Mehran

Publications and source records attributed to Roxana Mehran.

139 records · Page 8Linked to original sources
PubMed2002

Impact of normalized myocardial perfusion after successful angioplasty in acute myocardial infarction.

OBJECTIVES: We sought to evaluate and validate the ability of the angiographic myocardial blush grade to risk stratify patients after successful angioplasty in acute myocardial infarction (AMI). BACKGROUND: Although epicardial Thrombolysis In Myocardial Infarction (TIMI)-3 flow is restored in >90% of patients undergoing primary percutaneous coronary intervention (PCI), normal myocardial perfusion may be present less frequently and may detrimentally impact survival. METHODS: A cohort of 173 consecutive patients undergoing intervention within 24 h of AMI onset were studied. High-risk features of this population included failed thrombolysis in 39%, cardiogenic shock in 17% and saphenous vein graft culprit in 11% of patients. RESULTS: Despite the restoration of TIMI-3 flow in 163 (94.2%) patients, myocardial perfusion, as evidenced by normal contrast opacification of the myocardial bed subtended by the infarct artery (myocardial blush), was normal in only 29.4% of patients with TIMI-3 flow following PCI, and in no patient with TIMI 0 to 2 flow. In patients in whom TIMI-3 flow was restored, survival was strongly dependent on the myocardial perfusion grade; one-year cumulative mortality was 6.8% with normal myocardial blush, 13.2% with reduced myocardial blush and 18.3% in patients with absent myocardial blush (p = 0.004). CONCLUSIONS: Abnormal myocardial perfusion is present in most patients following primary or rescue PCI in AMI, despite restoration of brisk epicardial coronary flow. In high risk patients achieving TIMI-3 flow after intervention, the myocardial blush score may be used to stratify prognosis into excellent, intermediate and poor survival. Further study is warranted to examine whether adjunctive mechanical or pharmacologic strategies can further improve myocardial perfusion and survival of patients with acute myocardial infarction undergoing intervention.

Aged↗
PubMed2002

Quantitative angiographic methods for appropriate end-point analysis, edge-effect evaluation, and prediction of recurrent restenosis after coronary brachytherapy with gamma irradiation.

OBJECTIVES: The study was done to investigate the relationship between clinical restenosis and the relative angiographic location of the recurrent restenotic lesion, after treatment of in-stent restenosis with vascular brachytherapy in the Washington Radiation for In-Stent Restenosis Trial (WRIST). BACKGROUND: Intracoronary radiation therapy reduces recurrence of in-stent restenosis. We investigated the above objective in patients enrolled in WRIST. METHODS: The WRIST study randomized 130 patients to double-blinded therapy with gamma irradiation (iridium-192 [(192)Ir]) versus placebo after interventional treatment of diffuse in-stent restenosis. After the intervention and at follow-up, three vessel segments were individually analyzed with quantitative coronary angiography: 1) the "stent," 2) the "radiation ribbon," and 3) the "ribbon+margin" segment (including 5 mm on either end of the injured or radiation-ribbon segment). Receiver operator curves (ROC) were used to assess the value of the follow-up percent diameter stenosis (DS) for each of the three analyzed segments in predicting target vessel revascularization (TVR). RESULTS: (192)Ir reduced recurrent restenosis (23.7% vs. 60.7%, p < 0.001) and the length of recurrent restenosis (8.99 +/- 4.34 mm vs. 17.54 +/- 10.48 mm, p < 0.001) at follow-up compared to placebo. Isolated stent edge (3.4%) and ribbon edge (1.7%) restenoses were infrequent in both groups. The best angiographic surrogate of TVR was the 50% follow-up DS obtained from the ribbon+margin analysis (ROC area 0.806). CONCLUSIONS: In WRIST, not only was (192)Ir therapy effective in reducing restenosis, but it also reduced the lesion length of treatment failures by 50%, and it was not associated with edge proliferation. The restenosis rate obtained from the vessel segment inclusive of the dose fall-off zones was the best correlate of TVR and should become a standard analysis site in all vascular brachytherapy trials.

Brachytherapy↗
PubMed2002

Clinical outcome following percutaneous coronary interventions in patients with chronic renal failure.

The clinical outcome of patients with chronic renal failure (CRF) who undergo percutaneous coronary intervention (PCI) has not been systematically evaluated in a large cohort of patients. We retrospectively analyzed the in-hospital and 1-year clinical outcomes of 10,076 consecutive patients who underwent PCI between January 1994 and December 1997. A total of 95 patients (0.9%) had end-stage renal disease (ESRD) on dialysis, 786 patients (7.8%) had CRF, and 9,125 patients (90.6%) had normal renal function. Despite an angiographic success rate of 97% in all three groups, in-hospital mortality was significantly higher among patients with renal disease, whether they were on dialysis or not, when compared to patients without renal dysfunction (6.8% vs. 4.2% vs. 0.9%; P < 0.0001). At 1-year follow-up, mortality rate was 48.8% for ESRD, 25.7% for patients with CRF, and 5.5%, for patients without renal dysfunction (P < 0.0001). By multivariate analysis, high left ventricular ejection fraction and creatinine clearance were associated with decreased late mortality (OR = 0.84 and 0.95; P < 0.0001), whereas ESRD (OR = 3.65; P = 0.0002), non-Q-wave myocardial infarction (OR = 2.21; P < 0.0001), diabetes mellitus (OR = 1.99; P < 0.0001), and CRF (OR = 1.74; P = 0.003) were independent correlates of increased late mortality. Therefore, PCI in patients with impaired renal function, whether on dialysis or not, is associated with poor in-hospital and 1-year survival.

Aged↗
PubMed2002

Estrogen-eluting, phosphorylcholine-coated stent implantation is associated with reduced neointimal formation but no delay in vascular repair in a porcine coronary model.

Estrogen can inhibit intimal proliferation and accelerate endothelial regeneration after angioplasty. This suggests that estrogen may prevent in-stent restenosis. Unlike other therapies to prevent restenosis, estrogen may also not delay endothelial regrowth, thereby avoiding the risk of late stent thrombosis. The purpose of this work was to determine the effect of a 17beta-estradiol-eluting stent on neointimal formation in a porcine model. Each artery of six pigs was randomized to either a control, low-dose, or high-dose 17beta-estradiol-eluting stent. All animals were sacrificed at 30 days for histopathological analysis. There was a 40% reduction in intimal area in the high-dose stents compared with control stents (2.54 +/- 1.0 vs. 4.13 +/- 1.1 mm(2), for high dose vs. control, respectively; P < 0.05). There was complete endothelial regeneration at 30 days and similar inflammatory response to stenting on histopathology in all the stent groups. This is the first study to show that 17beta-estradiol-eluting stents are associated with reduced neointimal formation without affecting endothelial regeneration in the pig model of in-stent restenosis. Estrogen-coated stents may have a potential benefit in the prevention and treatment of in-stent restenosis.

Animals↗
PubMed2002

New-device angioplasty in women: clinical outcome and predictors in a 7,372-patient registry.

BACKGROUND: Female gender has been identified as an independent predictor of early complications and mortality after conventional balloon angioplasty. To gain insight into the outcome of women after new-device angioplasty, we reviewed the early and late clinical outcome of 7,372 patients undergoing new-device angioplasty between 1991 and 1996 at the Washington Hospital Center. METHODS: Patients (2,077 women and 5,295 men) with native coronary artery (82.5%) or saphenous vein graft lesions undergoing new-device angioplasty were included in the study. In-hospital and 1-year major adverse cardiac events (MACE), including death, myocardial infarction, and target lesion revascularization (TLR), were recorded and compared on the basis of gender. Multivariable logistic regression analysis was performed to identify predictors of in-hospital and late mortality, follow-up MACE, and TLR. RESULTS: Women had more baseline comorbid risk factors and smaller reference vessel size compared with men. Women had a higher in-hospital cardiac mortality (1.39% vs 0.66%, P = 0.002), TLR (2.78% vs 1.81%, P = 0.008), and congestive heart failure (4.18% vs 2.29%, P < 0.001) compared with men. Overall in-hospital MACE tended to be higher among women (4.2% vs 3.3%, P = 0.074). Women had a higher 1-year mortality rate (4.39% vs 3.26%, P = 0.018), but a lower follow-up TLR (15.0% vs 18.1%, P = 0.001) and a lower overall MACE rate (29.2% vs 32.7%, P = 0.007) compared with men. Female gender was an independent predictor of in-hospital mortality (odds ratio 2.28, P = 0.02), but not late mortality. CONCLUSIONS: Although female gender appears to carry an inherent risk of in-hospital mortality after new-device angioplasty, the procedural success and mortality rates are favorable compared with those associated with balloon angioplasty series. The long-term clinical outcome of women after new-device angioplasty is excellent. The use of new devices is a safe and effective alternative strategy for the treatment of women with ischemic coronary artery disease. Device-specific outcomes, including stents, will require further evaluation.

Angioplasty↗
PubMed2002

Acute angiographic and clinical results of the NIR w/SOX stent.

Acute angiographic and clinical results of the NIR w/SOX stent (Boston Scientific/Scimed, Inc., Maple Grove, Minnesota) were evaluated. Between March 2000 and May 2000, a total of 102 lesions in 88 patients underwent stenting with the NIR w/SOX stent. The reference vessel diameter and lesion length were 2.97 +/- 0.50 mm and 16.2 +/- 6.5 mm, respectively. The minimal lumen diameter increased from 0.68 +/- 0.45 to 3.07 +/- 0.50 mm. Stent delivery failure was observed in 4 lesions (3.9%). On the other hand, the NIR w/SOX stent was successfully delivered in 7 of 9 lesions that had unsuccessful delivery of other kinds of stents. Angiographic success was observed in all except 1 lesion where the NIR w/SOX stents could not be delivered. There were no procedural myocardial infarctions or deaths. In one case, procedural coronary bypass surgery was performed. There was no acute closure or subacute stent thrombosis. Despite unfavorable lesion characteristics, the NIR w/SOX stent achieves high procedural success and acceptable stent delivery. Furthermore, it may have a high probability to be delivered in lesions where other kinds of stent result in unsuccessful delivery.

Aged↗
PubMed2001

Intravascular-ultrasound-guided percutaneous transluminal coronary angioplasty/provisional stent implantation strategy: impact on long-term clinical follow-up.

Two hundred and eighty-four consecutive patients with 438 native coronary artery stenoses were enrolled prospectively in a study of intravascular ultrasound (IVUS)-guided percutaneous transluminal coronary angioplasty (PTCA) with provisional stenting: (1) aggressive lesion-site media-to-media balloon-sizing; (2) IVUS-assessment of residual lumen dimensions to identify optimal PTCA results (minimum lumen area = 65% of the average of the proximal and distal reference lumen areas or = 6.0 mm(2) and no major dissection); and (3) liberal stent crossover. Overall, 206 stenoses in 134 patients (47%) were treated with PTCA alone. Reasons for crossover were flow-limiting or lumen-compromising dissections in 28% of patients and suboptimal IVUS minimum lumen area in 72% of patients. At one year, 8% of stenoses in the PTCA group and 16% in the stent crossover group required revascularization. In approximately half of the patients treated using an IVUS-guided aggressive PTCA strategy, stent implantation could be avoided without sacrificing an increase in acute complications or worse clinical outcome.

Journal Article↗
PubMed2001

Update on In-stent Restenosis.

Although stents mitigate the risk of restenosis, in-stent restenosis (ISR) is still an important clinical problem. ISR usually occurs within the first 3 to 6 months after stenting, with little progression thereafter. ISR progresses through four distinct phases: thrombosis, inflammation, proliferation, and vessel remodeling. Platelets and macrophages play a crucial role in the formation of neointimal tissue via stimulation of vascular smooth muscle migration and proliferation at the injury site. The angiographic pattern of ISR conveys prognostic information on subsequent target vessel revascularization with diffuse proliferative ISR, with total occlusion having the worst prognosis. Stent length and final minimal lumen diameter are additional predictors of ISR. Certain gene polymorphisms may increase the risk of developing ISR. No curative therapeutic modality for ISR has been found; efforts have been focusing on prevention. In this regard, intracoronary radiation therapy has shown the best results, although the promise of several technologies, particularly the drug-eluting stents, will likely result in further reductions (or perhaps irradiation) in the incidence of ISR.

Journal Article↗
PubMedDate not supplied

Complete vascular healing and sustained suppression of neointimal thickening after local delivery of advanced c-myc antisense at six months follow-up in a rabbit balloon injury model.

BACKGROUND: Neointimal hyperplasia following percutaneous transluminal coronary angioplasty (PTCA) is one of the major components of the process of restenosis. We evaluated the long-term impact of local delivery of c-myc neutrally charged antisense oligonucleotides (Resten-NG) upon neointimal formation following PTCA in a rabbit model. METHODS: PTCA was performed in the iliac arteries of 10 New Zealand white rabbits at 8 atm for 30 s, three times. An infusion of 500 micro g Resten-NG (n=6) or saline (n=4) was delivered to the site at 2 atm via the outer balloon pores of the transport catheter over 2 min. The diet was supplemented with 0.25% cholesterol for 10 days before and 6 months following PTCA. RESULTS: After 6 months, animals were sacrificed and vessels were fixed in formalin, processed and stained with hematoxylin, eosin, and movat. Histological analysis revealed complete vascular healing in both groups of animals. Planimetry showed that intimal areas were 1.71+/-0.25 and 0.65+/-0.36 mm2 in the control and antisense delivery groups, respectively (P<.05). CONCLUSION: We conclude that local delivery of Resten-NG significantly inhibited neointimal thickening following PTCA in a rabbit for up to 6 months.

Angioplasty, Balloon, Coronary↗