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Roxana Mehran

Publications and source records attributed to Roxana Mehran.

At least 73 records · Page 4Linked to original sources
PubMed2005

An Internet-based registry examining the efficacy of heparin coating in patients undergoing coronary stent implantation.

BACKGROUND: Heparin coating is an attractive alternative to counterbalance intrinsic stent thrombogenicity and to decrease the incidence of stent thrombosis. METHODS: We compared, based on the data of an international multicenter prospective registry, the rates of stent thrombosis after percutaneous coronary interventions in native coronary arteries using a Bx VELOCITY heparin-coated stent versus a bare metal stent of the same design in a total of 3098 patients at high risk for stent thrombosis. Most patients in both groups underwent percutaneous coronary intervention for unstable angina (48.4% vs 47.5%, respectively) with > 25% of the patients treated for acute myocardial infarction (30.8% and 28.1%, respectively). RESULTS: Procedural success was high and very similar in patients with heparin-coated and bare metal stents (99.3% vs 98.8%, respectively, P = .11). The primary end point, a 30-day stent thrombosis, occurred in 0.6% of the 1417 patients treated with the heparin-coated stent and 0.9% of the 1681 patients treated with the bare metal stent (relative risk reduction 33%, P = .41). The rates of cardiac death, myocardial infarction, and target lesion revascularization did not differ significantly between the groups. By multivariate analysis, variables independently associated with 30-day stent thrombosis included the evidence of thrombus at baseline (odds ratio [OR] 3.0, 95% CI 1.29-7.0, P = .01), small vessel stenting (OR 2.41, 95% CI 1.01-5.74, P = .05), and target left anterior descending artery (OR 2.32, 95% CI 1.00-5.38, P = .05). CONCLUSION: This large-scale registry comparing the use of heparin-coated stent versus bare metal stent in the reality of daily practice showed no significant difference in stent thrombosis in patients with a high-risk profile for thrombotic complications.

Angina, Unstable↗
PubMed2005

Impact of moderate renal insufficiency on restenosis and adverse clinical events after paclitaxel-eluting and bare metal stent implantation: results from the TAXUS-IV Trial.

BACKGROUND: Mortality and restenosis may be increased in patients with mild to moderate renal insufficiency (RI) after coronary stent implantation. Whether drug-eluting stents safely reduce restenosis and enhance event-free survival in these patients is unknown. We sought to evaluate the impact of baseline RI on clinical and angiographic outcomes in patients undergoing elective percutaneous coronary intervention using either bare metal or paclitaxel-eluting stents. METHODS: In the TAXUS-IV trial, 1314 patients were randomized to either the polymer-based paclitaxel-eluting TAXUS stent or an identical-appearing bare metal stent. Outcomes were stratified on the basis of the presence of RI, defined as a baseline creatinine clearance < 60 cm3/min calculated by the Cockcroft-Gault formula. RESULTS: Baseline RI was present in 223 (17.2%) patients, in whom the mean creatinine clearance was 49.6 +/- 8.5 cm3/min. Compared with bare metal stents, treatment with the TAXUS stent resulted in lower rates of 9-month angiographic restenosis rates in both patients with (2.1% vs 20.5%, P = .009) and without (9.2% vs 27.8%, P < .0001) baseline RI. Similarly, 1-year target lesion revascularization rates were reduced with the TAXUS stent in patients with (3.3% vs 12.2%, P = .01) and without (4.7% vs 15.8%, P < .0001) baseline RI. The occurrence of death, myocardial infarction, and stent thrombosis at 1 year were similar in both randomization groups, independent of renal function. CONCLUSIONS: The polymer-based paclitaxel-eluting TAXUS stent safely reduces clinical and angiographic restenosis in patients with preserved as well as moderate impairment of baseline renal function.

Aged↗
PubMed2005

Low hematocrit predicts contrast-induced nephropathy after percutaneous coronary interventions.

BACKGROUND: The relationship between low hematocrit and contrast-induced nephropathy has not been investigated. METHODS: Of 6,773 consecutive patients treated with percutaneous coronary intervention, contrast-induced nephropathy (an increase of >/=25% or >/=0.5 mg/dL in preprocedure serum creatinine, at 48 hours postprocedure) occurred in 942 (13.9%) patients. RESULTS: Rates of contrast-induced nephropathy steadily increased as baseline hematocrit quintile decreased (from 10.3% in the highest quintile to 23.3% in the lowest quintile) (chi(2) for trend, P < 0.0001). Stratification by baseline estimated glomerular filtration rate (eGFR) and baseline hematocrit showed that the rates of contrast-induced nephropathy were the highest (28.8%) in patients who had the lowest level for both baseline eGFR and hematocrit. Patients with the lowest eGFR but relatively high baseline hematocrit values had remarkably lower rates of contrast-induced nephropathy (15.8%, 12.3%, 17.1%, and 15.4% in 2nd, 3rd, 4th, and 5th quintiles of baseline hematocrit, respectively) (P < 0.0001). The rates of contrast-induced nephropathy increased with increment in change in hematocrit. Patients in the lowest quintile of baseline hematocrit with absolute hematocrit drop >5.9% had almost doubled rates of contrast-induced nephropathy compared with patients with hematocrit change <3.4% (38.1% vs. 18.8%, respectively) (P < 0.0001). By multivariate analysis, lower baseline hematocrit was an independent predictor of contrast-induced nephropathy; each 3% decrease in baseline hematocrit resulted in a significant increase in the odds of contrast-induced nephropathy in patients with and without chronic kidney disease (11% and 23%, respectively). When introduced into the multivariate model instead of baseline hematocrit, change in hematocrit also showed a significant association with contrast-induced nephropathy. CONCLUSION: Lower hematocrit is an important risk factor for contrast-induced nephropathy. Whether correcting the hematocrit prepercutaneous coronary intervention might decrease the rates of contrast-induced nephropathy should be addressed in a prospectively designed trial.

Adult↗
PubMed2004

Nonuniform strut distribution correlates with more neointimal hyperplasia after sirolimus-eluting stent implantation.

BACKGROUND: Little is known about causes of intimal hyperplasia (IH) after sirolimus-eluting stent (SES) implantation. METHODS AND RESULTS: Intravascular ultrasound was performed in 24 lesions with intra-SES restenosis and a comparison group of 25 nonrestenotic SESs. To assess stent strut distribution, the maximum interstrut angle was measured with a protractor centered on the stent, and the visible struts were counted and normalized for the number of stent cells. In SES restenosis patients, minimum lumen site was compared with image slices 2.5, 5.0, 7.5, and 10.0 mm proximal and distal to this site. The minimum lumen site had a smaller IVUS lumen area at follow-up (2.7+/-0.9 versus 6.2+/-1.9 mm2; P<0.01), larger maximum interstrut angle (135+/-39 degrees versus 72+/-23 degrees; P<0.01), larger IH area (3.4+/-1.5 versus 0.6+/-1.1 mm2; P<0.01) and thickness (0.7+/-0.3 versus 0.1+/-0.2 mm; P<0.01) at maximum interstrut angle, and fewer stent struts (4.9+/-1.0 versus 6.0+/-0.5; P<0.01) even when normalized for the number of stent cells (0.78+/-0.15 versus 0.97+/-0.07; P<0.01). Compared with nonrestenotic SES, the restenosis lesions also had a smaller minimal lumen area, larger IH area, thicker IH at maximum interstrut angle, fewer stent struts, and larger maximum interstrut angle. Multivariate analysis identified the number of visualized stent struts normalized for the number of stent cells and maximum interstrut angle as the only independent IVUS predictor of IH cross-sectional area (P<0.01 and P<0.01), minimum lumen area (P<0.01 and P<0.01), and IH thickness (P<0.01 and P<0.01). CONCLUSIONS: The number and distribution of stent struts affect the amount of neointima after SES implantation.

Aged↗
PubMed2004

Predictors of and outcomes of early thrombosis following balloon angioplasty versus primary stenting in acute myocardial infarction and usefulness of abciximab (the CADILLAC trial).

We sought to identify the predictors and clinical outcomes of early thrombosis after primary angioplasty and stenting for acute myocardial infarction (AMI). Little is known about the correlates and prognosis of acute and subacute thromboses after percutaneous coronary intervention (PCI) for AMI. We therefore studied the frequency, clinical determinants, and implications of early thrombosis in a large trial of patients who had primary PCI. In the Controlled Abciximab and Device Investigation to Lower Late Angioplasty Complications trial, 2,082 patients who had AMI were randomized in a 2 x 2 factorial design to primary stenting or to balloon angioplasty, each with and without abciximab. Early thrombosis occurred in 19 patients (0.9%) at a median of 2 days (range 0 to 23). Maximal balloon diameter was smaller, and aneurysmal and bifurcation lesions were more prevalent in the group with early thrombosis. Early thrombosis occurred in 0.4% of patients who had been randomized to receive abciximab versus 1.5% of control patients (p <0.01) and in 0.5% of patients who had been randomized to undergo stenting versus 1.4% of those who underwent balloon angioplasty (p = 0.04). By multivariate analysis, abciximab use was an independent predictor of no thrombosis (hazard ratio 0.27, 95% confidence interval 0.09 to 0.86, p = 0.026). Within 30 days, 5.3% of patients who had early thrombosis died, 32.9% developed reinfarction, and 89.5% required repeat target vessel revascularization (including bypass surgery in 11.1%). As a result, patients who had versus those who did not have early thrombosis had markedly higher rates of major adverse cardiac events at 30 days (94.7% vs 5.0%, p <0.0001) and at 1 year (94.7% vs 16.9%, p <0.0001). Patients who develop early thrombosis after primary PCI have a very high rate of major adverse cardiac events, including death and reinfarction, and usually require repeat coronary angioplasty or surgery for management. Complex baseline angiographic morphology and smaller maximal balloon diameter are predictors of early thrombosis after primary PCI for AMI. The incidence of early thrombosis after primary angioplasty and stenting is decreased by abciximab use.

Abciximab↗
PubMed2004

Impact of anemia on outcomes of patients undergoing percutaneous coronary interventions.

Of 6,929 consecutive patients who were treated with percutaneous coronary intervention, 1,708 (24.6%) had anemia according to criteria of the World Health Organization. Compared with patients who did not have anemia, those who did have anemia were older, more frequently women and African-American, had a smaller body mass index, and higher frequencies of cardiovascular risk factors and co-morbid conditions. Patients who had anemia compared with those who did not have anemia had significantly (p <0.0001) higher mortality rates during hospitalization (1.9% vs 0.4%) and at 1 year (12.8% vs 3.5%). After adjustment for potential confounders, baseline hematocrit remained a significant predictor of a 1-year mortality rate (hazard ratio 0.93 per 1% increase in hematocrit, 95% confidence interval 0.91 to 0.95).

Aged↗
PubMed2004

A simple risk score for prediction of contrast-induced nephropathy after percutaneous coronary intervention: development and initial validation.

OBJECTIVES: We sought to develop a simple risk score of contrast-induced nephropathy (CIN) after percutaneous coronary intervention (PCI). BACKGROUND: Although several risk factors for CIN have been identified, the cumulative risk rendered by their combination is unknown. METHODS: A total of 8,357 patients were randomly assigned to a development and a validation dataset. The baseline clinical and procedural characteristics of the 5,571 patients in the development dataset were considered as candidate univariate predictors of CIN (increase >or=25% and/or >or=0.5 mg/dl in serum creatinine at 48 h after PCI vs. baseline). Multivariate logistic regression was then used to identify independent predictors of CIN with a p value <0.0001. Based on the odds ratio, eight identified variables (hypotension, intra-aortic balloon pump, congestive heart failure, chronic kidney disease, diabetes, age >75 years, anemia, and volume of contrast) were assigned a weighted integer; the sum of the integers was a total risk score for each patient. RESULTS: The overall occurrence of CIN in the development set was 13.1% (range 7.5% to 57.3% for a low [ or=16] risk score, respectively); the rate of CIN increased exponentially with increasing risk score (Cochran Armitage chi-square, p < 0.0001). In the 2,786 patients of the validation dataset, the model demonstrated good discriminative power (c statistic = 0.67); the increasing risk score was again strongly associated with CIN (range 8.4% to 55.9% for a low and high risk score, respectively). CONCLUSIONS: The risk of CIN after PCI can be simply assessed using readily available information. This risk score can be used for both clinical and investigational purposes.

Aged↗
PubMed2004

Vascular complications associated with arteriotomy closure devices in patients undergoing percutaneous coronary procedures: a meta-analysis.

OBJECTIVES: This study was designed to assess the safety of arteriotomy closure devices (ACDs) versus mechanical compression by meta-analysis in patients undergoing percutaneous transfemoral coronary procedures. BACKGROUND: Although ACDs are widely applied for hemostasis after percutaneous endovascular procedures, their safety is controversial. METHODS: Randomized, case-control, and cohort studies comparing access-related complications using ACDs versus mechanical compression were analyzed. The primary end point was the cumulative incidence of vascular complications, including pseudoaneurysm, arteriovenous fistula, retroperitoneal hematoma, femoral artery thrombosis, surgical vascular repair, access site infection, and blood transfusion. RESULTS: A total of 30 studies involving 37,066 patients were identified. No difference in complication incidence between Angio-Seal and mechanical compression was revealed in the diagnostic (Dx) setting (odds ratio [OR] 1.08, 95% confidence interval [CI] 0.11 to 10.0) or percutaneous coronary interventions (PCI) (OR 0.86, 95% CI 0.65 to 1.12). Meta-analysis of randomized trials only showed a trend toward less complications using Angio-Seal in a PCI setting (OR 0.46, 95% CI 0.20 to 1.04; p = 0.062). No differences were observed regarding Perclose in either Dx (OR 1.51, 95% CI 0.24 to 9.47) or PCI (OR 1.21, 95% CI 0.94 to 1.54) setting. An increased risk in complication rates using VasoSeal in the PCI setting (OR 2.25, 95% CI 1.07 to 4.71) was found. The overall analysis favored mechanical compression over ACD (OR 1.34, 95% CI 1.01 to 1.79). CONCLUSIONS: In the setting of Dx angiography, the risk of access-site-related complications was similar for ACD compared with mechanical compression. In the setting of PCI, the rate of complications appeared higher with VasoSeal.

Angioplasty, Balloon, Coronary↗
PubMed2004

Prognostic utility of comparative methods for assessment of ST-segment resolution after primary angioplasty for acute myocardial infarction: the Controlled Abciximab and Device Investigation to Lower Late Angioplasty Complications (CADILLAC) trial.

OBJECTIVE: This study was done to assess and compare the prognostic significance of multiple methods for measuring ST-segment elevation resolution (STR) following primary percutaneous coronary intervention (PCI). BACKGROUND: Resolution of ST-segment elevation (STE) is a powerful predictor of both infarct-related artery patency and mortality in acute myocardial infarction (AMI). Recent thrombolytic studies have suggested that simple measures of STR may be as powerful as more complex algorithms. The optimal method of assessing STR following primary PCI has not been studied. METHODS: We analyzed 700 patients with technically adequate baseline and post-PCI electrocardiograms from the Controlled Abciximab and Device Investigation to Lower Late Angioplasty Complications (CADILLAC) trial. Five methods were used to assess STR: 1) summed %STR across multiple leads (SigmaSTR); 2) %STR in the single lead with maximum baseline STE (MaxSTR); 3) absolute maximum STE before the procedure; 4) absolute maximum STE after intervention (MaxSTPost); and 5) a categorical variable based upon MaxSTPost (High Risk). RESULTS: At 30 days, SigmaSTR, MaxSTR, and MaxSTPost all correlated strongly with mortality (p = 0.004, p = 0.005, and p < 0.0001, respectively) and the combined end point of mortality or reinfarction (p = 0.001, p = 0.001, and p < 0.0001). At one year, SigmaSTR and MaxSTPost correlated with mortality (p = 0.04, p = 0.0001), reinfarction (p = 0.02, p = 0.0015), and the combined end point (p = 0.02, p < 0.0001). By multivariate analysis, only the simpler measures of MaxSTPost and High Risk categorization independently predicted all outcomes at both time points. CONCLUSIONS: The STR following primary PCI in AMI correlates strongly with mortality and reinfarction, independent of target vessel patency. The simple measure of the maximal residual degree of STE after primary PCI is a strong independent predictor of both survival and freedom from reinfarction at 30 days and 1 year.

Aged↗
PubMed2004

Outcome in elderly patients undergoing primary coronary intervention for acute myocardial infarction: results from the Controlled Abciximab and Device Investigation to Lower Late Angioplasty Complications (CADILLAC) trial.

BACKGROUND: Biological age is a strong determinant of prognosis in patients with acute myocardial infarction (AMI). We sought to examine the impact of age after primary percutaneous coronary intervention in AMI and to determine whether routine coronary stent implantation and/or platelet glycoprotein IIb/IIIa inhibitors improve clinical outcomes in elderly patients after primary angioplasty. METHODS AND RESULTS: In the CADILLAC trial, 2082 patients with AMI were randomized to balloon angioplasty, angioplasty plus abciximab, stenting alone, or stenting plus abciximab. No patient was excluded on the basis of advanced age; patients ranging from 21 to 95 years of age were enrolled. One-year mortality increased for each decile of age, exponentially after 65 years of age (1.6% for patients <55 years, 2.1% for 55 to 65 years, 7.1% for 65 to 75 years, 11.1% for patients >75 years; P<0.0001). Elderly patients also had increased rates of stroke and major bleeding compared with their younger counterparts. Among elderly patients (> or =65 years), 1-year rates of ischemic target revascularization (7.0% versus 17.6%; P<0.0001) and subacute or late thrombosis (0% versus 2.2%; P=0.005) were reduced with stenting compared with balloon angioplasty. Routine abciximab administration, although safe, was not of definite benefit in elderly patients. Rates of mortality, reinfarction, disabling stroke, and major bleeding in the elderly were independent of reperfusion modality. CONCLUSIONS: Despite contemporary mechanical reperfusion strategies, mortality, major bleeding, and stroke rates remain high in elderly patients undergoing primary percutaneous coronary intervention, outcomes that are not affected by stents or glycoprotein IIb/IIIa inhibitors. By reducing restenosis, however, stent implantation improves clinical outcomes in elderly patients with AMI.

Abciximab↗
PubMed2004

Magnitude and impact of treatment delays on weeknights and weekends in patients undergoing primary angioplasty for acute myocardial infarction (the cadillac trial).

In 2,082 patients in the CADILLAC trial, the outcomes of patients presenting during peak hours were compared with those presenting during peak hours (Monday to Friday 8a.m. to 8 p.m., n = 1,047, 51%) were compared with those of patients presenting during off-peak hours (weeknights from 8 p.m. to 8 a.m. and weekends, n = 989, 49%). Although treatment times to percutaneous coronary intervention (PCI) were delayed approximately 21 minutes, in patients with acute myocardial infarctions occurring on weeknights and weekends, this modest delay did not adversely affect procedural success, myocardial recovery, or survival after PCI.

Aged↗
PubMed2004

Impact of anemia in patients with acute myocardial infarction undergoing primary percutaneous coronary intervention: analysis from the Controlled Abciximab and Device Investigation to Lower Late Angioplasty Complications (CADILLAC) Trial.

OBJECTIVES: We sought to investigate the impact of anemia in patients with acute myocardial infarction (AMI) undergoing primary percutaneous coronary intervention (PCI). BACKGROUND: The prognostic importance of anemia on primary PCI outcomes is unknown. METHODS: In the Controlled Abciximab and Device Investigation to Lower Late Angioplasty Complications (CADILLAC) trial, 2,082 patients of any age with AMI within 12 h onset undergoing primary PCI were randomized to balloon angioplasty versus stenting, each +/- abciximab. Outcomes were stratified by the presence of anemia at baseline, as defined by World Health Organization criteria (hematocrit <39% for men and <36% for women). RESULTS: Anemia was present in 260 (12.8%) of 2,027 randomized patients with baseline laboratory values. Patients with versus without baseline anemia more frequently developed in-hospital hemorrhagic complications (6.2% vs. 2.4%, p = 0.002), had higher rates of blood product transfusions (13.1% vs. 3.1%, p < 0.0001), and had a prolonged (median 4.1 vs. 3.5 days, p < 0.0001) and more expensive (median costs $12,434 vs. $11,603, p = 0.002) index hospitalization. Patients with versus without anemia had strikingly higher mortality during hospitalization (4.6% vs. 1.1%, p = 0.0003), at 30 days (5.8% vs. 1.5%, p < 0.0001), and at 1 year (9.4% vs. 3.5%, p < 0.0001). The rates of disabling stroke at 30 days (0.8% vs. 0.1%, p = 0.005) and at 1 year (2.1% vs. 0.4%, p = 0.0007) were also significantly higher in patients with anemia. By multivariate analysis, anemia was an independent predictor of in-hospital mortality (hazard ratio, 3.26; p = 0.048) and one-year mortality (hazard ratio, 2.38; p = 0.016). CONCLUSIONS: Anemia at baseline in patients with AMI undergoing primary PCI is common, and is strongly associated with adverse outcomes and increased mortality.

Abciximab↗
PubMed2004

Impact of chronic kidney disease on prognosis of patients with diabetes mellitus treated with percutaneous coronary intervention.

Chronic kidney disease (CKD) is a frequent complication of diabetes mellitus. However, the role of CKD in outcomes of patients with diabetes who have undergone percutaneous coronary intervention (PCI) has not been studied specifically. Therefore, we investigated the impact of CKD on prognosis of patients with diabetes who underwent PCI. Of 1,575 diabetic patients who underwent PCI, 1,046 (66%) had preserved renal function, 492 (31%) had CKD (baseline serum creatinine >1.5 mg/dl or estimated glomerular filtration rate <60 ml/min/1.73 m(2)) without dialysis, and 37 (2.3%) were dependent on dialysis. Patients with CKD versus those without CKD had more in-hospital complications, including mortality (2.6% vs 0.5%, respectively; p <0.0001), neurologic events (3.1% vs 0.6%, p = 0.0001), and gastrointestinal bleeding (2.9% vs 0.9%, p = 0.01). Contrast-induced nephropathy after PCI (increase > or =25% and/or > or =0.5 mg/dl of serum creatinine before PCI vs 48 hours after PCI) was found in 15% of patients without CKD versus 27% of those with CKD, and de novo dialysis was instituted in 0.1% versus 3.1%, respectively. Contrast-induced nephropathy was independently predicted (all p <0.0001) by peri-PCI hypotension (odds ratio [OR] 2.62), insulin treatment (OR 1.84), and volume of contrast medium (OR 1.30). The 1-year mortality rate was strikingly higher (all p <0.0001) in patients with CKD who did not receive dialysis (16%) and those on dialysis (44%) compared with the group with preserved renal function (5%). Contrast-induced nephropathy was among the independent predictors of a 1-year mortality rate (OR 2.75, p <0.001).

Age Factors↗
PubMed2004

Frequency, correlates, and clinical implications of myocardial perfusion after primary angioplasty and stenting, with and without glycoprotein IIb/IIIa inhibition, in acute myocardial infarction.

OBJECTIVES: We sought to determine the prognostic importance of myocardial reperfusion after various contemporary interventional strategies in patients with acute myocardial infarction (AMI). BACKGROUND: The frequency, correlates, and clinical implications of myocardial perfusion after primary angioplasty in AMI have not been examined in a large-scale prospective study. Similarly, whether glycoprotein (GP) IIb/IIIa inhibitors and/or stents improve myocardial perfusion beyond balloon angioplasty has not been investigated. METHODS: Tissue-level perfusion assessed by the myocardial blush grade was evaluated in 1,301 patients with AMI randomized to balloon angioplasty versus stenting, each with or without abciximab. RESULTS: Despite Thrombolysis In Myocardial Infarction flow grade 3 restoration in 96.1% of patients, myocardial perfusion was normal in only 17.4% of patients, reduced in 33.9%, and absent in 48.7%. Myocardial perfusion status post-coronary intervention stratified patients into three distinct risk categories, with 1-year mortality rates of 1.4% (normal blush), 4.1% (reduced blush), and 6.2% (absent blush) (p = 0.01). Among patients randomized to angioplasty, angioplasty + abciximab, stenting, and stenting + abciximab, normal myocardial perfusion was restored in 17.7%, 17.0%, 17.5%, and 17.6%, respectively (p = 0.95), which was associated with similar 1-year rates of mortality in patients randomized to stenting versus angioplasty (4.5% vs. 4.8%, p = 0.91) and abciximab versus no abciximab (4.3% vs. 5.0%, p = 0.63). CONCLUSIONS: Restoration of normal tissue-level perfusion is a powerful determinate of survival after primary PCI in AMI and is achieved in a minority of patients. Neither stents nor GP IIb/IIIa inhibitors significantly enhance myocardial perfusion compared to balloon angioplasty alone, underlying the similar long-term mortality with these different mechanical reperfusion strategies.

Abciximab↗