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American Journal of Cardiology | 2011

Post-traumatic Stress Disorder, Coronary Atherosclerosis, and Mortality

Naser Ahmadi; Fereshteh Hajsadeghi; Hormoz B. Mirshkarlo; Matthew J. Budoff; Rachel Yehuda; Ramin Ebrahimi

Post-traumatic stress disorder (PTSD) is associated with increased risk of multiple medical problems including myocardial infarction. However, a direct link between PTSD and atherosclerotic coronary artery disease (CAD) has not been made. Coronary artery calcium (CAC) score is an excellent method to detect atherosclerosis. This study investigated the association of PTSD to atherosclerotic CAD and mortality. Six hundred thirty-seven veterans without known CAD (61 ± 9 years of age, 12.2% women) underwent CAC scanning for clinical indications and their psychological health status (PTSD vs non-PTSD) was evaluated. In subjects with PTSD, CAC was more prevalent than in the non-PTSD cohort (76.1% vs 59%, p = 0.001) and their CAC scores were significantly higher in each Framingham risk score category compared to the non-PTSD group. Multivariable generalized linear regression analysis identified PTSD as an independent predictor of presence and extent of atherosclerotic CAD (p <0.01). During a mean follow-up of 42 months, the death rate was higher in the PTSD compared to the non-PTSD group (15, 17.1%, vs 57, 10.4%, p = 0.003). Multivariable survival regression analyses revealed a significant linkage between PTSD and mortality and between CAC and mortality. After adjustment for risk factors, relative risk (RR) of death was 1.48 (95% confidence interval [CI] 1.03 to 2.91, p = 0.01) in subjects with PTSD and CAC score >0 compared to subjects without PTSD and CAC score equal to 0. With a CAC score equal to 0, risk of death was not different between subjects with and without PTSD (RR 1.04, 95% CI 0.67 to 6.82, p = 0.4). Risk of death in each CAC category was higher in subjects with PTSD compared to matched subjects without PTSD (RRs 1.23 for CAC scores 1 to 100, 1.51 for CAC scores 101 to 400, and 1.81 for CAC scores ≥400, p <0.05 for all comparisons). In conclusion, PTSD is associated with presence and severity of coronary atherosclerosis and predicts mortality independent of age, gender, and conventional risk factors.


Journal of the American College of Cardiology | 2009

Outcomes Following Pre-Operative Clopidogrel Administration in Patients With Acute Coronary Syndromes Undergoing Coronary Artery Bypass Surgery The ACUITY (Acute Catheterization and Urgent Intervention Triage strategY) Trial

Ramin Ebrahimi; Cornelius M. Dyke; Roxana Mehran; Steven V. Manoukian; Frederick Feit; David A. Cox; Bernard J. Gersh; E. Magnus Ohman; Harvey D. White; Jeffrey W. Moses; James H. Ware; A. Michael Lincoff; Gregg W. Stone

OBJECTIVES This study sought to evaluate the impact of upstream clopidogrel in patients with non-ST-segment elevation acute coronary syndromes (NSTE-ACS) requiring coronary artery bypass grafting (CABG) from the ACUITY (Acute Catheterization and Urgent Intervention Triage strategY) trial. BACKGROUND Despite benefits of clopidogrel in patients with NSTE-ACS undergoing percutaneous coronary intervention, this agent is often not administered upstream (before angiography) as recommended by the American College of Cardiology/American Heart Association guidelines because of potential bleeding in the minority of patients who require CABG. METHODS The ACUITY trial enrolled 13,819 patients with NSTE-ACS undergoing early invasive management. The timing of clopidogrel initiation was per investigator discretion. A 5-day washout period before CABG was recommended for patients having received clopidogrel. RESULTS Of 13,819 patients enrolled, 1,539 (11.1%) underwent CABG before discharge. Clopidogrel-exposed patients had a longer median duration of hospitalization (12.0 days vs. 8.9 days, p < 0.0001), but fewer adverse composite ischemic events (death, myocardial infarction, or unplanned revascularization) at 30 days; 12.7% vs. 17.3%, p = 0.01), with nonsignificantly different rates of non-CABG-related major bleeding (3.4% vs. 3.2%, p = 0.87) and post-CABG major bleeding (50.3% vs. 50.9%, p = 0.83) compared with those patients not administered clopidogrel. By multivariable analysis, clopidogrel use before CABG was an independent predictor of reduced 30-day composite ischemia (odds ratio: 0.67, 95% confidence interval: 0.48 to 0.92, p = 0.001) but not of increased post-CABG major bleeding (odds ratio: 0.98, 95% confidence interval: 0.80 to 1.19, p = 0.80). CONCLUSIONS Clopidogrel administration before catheterization in patients with NSTE-ACS requiring CABG is associated with significantly fewer 30-day adverse ischemic events without significantly increasing major bleeding, compared to withholding clopidogrel until after angiography. These findings support the American College of Cardiology/American Heart Association guidelines for upstream clopidogrel administration in all NSTE-ACS patients, including those who subsequently undergo CABG. (Comparison of Angiomax Versus Heparin in Acute Coronary Syndromes [ACS]; NCT00093158).


Journal of Acquired Immune Deficiency Syndromes | 2006

Pharmacokinetics and safety of tenofovir disoproxil fumarate on coadministration with lopinavir/ritonavir.

Brian P. Kearney; Anita Mathias; Angelique Mittan; John Sayre; Ramin Ebrahimi; Andrew K. Cheng

Objective:Lopinavir/ritonavir (LPV/r) and tenofovir disoproxil fumarate (TDF) are frequently used antiretrovirals. A pharmacokinetic study in healthy volunteers was conducted to assess the potential for a drug interaction between these agents. Methods:This was a 36-day, multiple-dose, drug-drug interaction study of TDF and lopinavir/ritonavir (LPV/r). Subjects received TDF alone for 7 days, followed by 14 days each of TDF plus LPV/r and LPV/r alone in a randomized manner. Pharmacokinetic assessments were performed over 24 hours on days 7, 21, and 35. LPV/r and tenofovir plasma/serum concentrations were measured by high-performance liquid chromatography/mass spectometry (MS)/MS. Geometric mean ratios and 90% confidence intervals of pharmacokinetic parameters for tenofovir, LPV, and ritonavir (RTV) were estimated using analysis of variance and compared with the no-effect criterion for pharmacokinetic equivalence. Results:Tenofovir measurements with an area under the concentration-time curve over the dosing interval, maximum concentration, and concentration at the end of the dosing interval (Cτ) were 32%, 15%, and 51% higher, respectively, when TDF was coadministered with LPV/r (n = 24). LPV and RTV pharmacokinetics, including Cτ, were unaffected by TDF (n = 24). Clinical estimates of renal function were unaffected by administration of TDF alone or with LPV/r. Discussion:Coadministration of TDF with LPV/r resulted in increased tenofovir exposures at steady state, possibly through increased absorption. This increase is not believed to be clinically relevant based on the safety and efficacy of TDF plus LPV/r-containing regimens in HIV-infected patients in long-term controlled clinical trials.


Journal of Acquired Immune Deficiency Syndromes | 2009

Simplification of antiretroviral therapy to a single-tablet regimen consisting of efavirenz, emtricitabine, and tenofovir disoproxil fumarate versus unmodified antiretroviral therapy in virologically suppressed HIV-1-infected patients.

Edwin DeJesus; Benjamin Young; Javier O Morales-Ramirez; Louis Sloan; Douglas J. Ward; John F. Flaherty; Ramin Ebrahimi; Jf Maa; Karen Reilly; Janet Ecker; Damian McColl; Daniel Seekins; Awny Farajallah

Objective:To evaluate a simplification strategy for HIV-1-infected patients virologically suppressed on antiretroviral therapy (ART) by switching to a single-tablet regimen consisting of efavirenz/emtricitabine/tenofovir disoproxil fumarate (EFV/FTC/TDF). Design:Prospective, randomized, controlled, open-label, multicenter study. Methods:Patients on stable ART with HIV-1 RNA <200 copies per milliliter for ≥3 months were stratified by prior nonnucleoside reverse transcriptase inhibitor-based or protease inhibitor-based therapy and randomized (2:1) to simplify treatment to EFV/FTC/TDF or to stay on their baseline regimen (SBR). Efficacy and safety assessments were performed at baseline and at weeks 4, 12, 24, 36, and 48. Additional patient-reported outcomes included the following: adherence by visual analog scale, quality of life by SF-36 (v2) survey, HIV Symptom Index, and the Preference of Medication and Perceived Ease of the Regimen for Condition questionnaires. Results:Three hundred patients (EFV/FTC/TDF 203, SBR 97) were evaluated (prior protease inhibitor-based ART, 53%; nonnucleoside reverse transcriptase inhibitor-based ART, 47%). The arms were well balanced at baseline with 88% males, 29% blacks, and a mean age of 43 years; CD4 was 540 cells per cubic millimeter, 96% had HIV-1 RNA <50 copies per milliliter, and 88% were on their first ART regimen. Through 48 weeks, 89% vs. 88% in the EFV/FTC/TDF vs. SBR arms, respectively, maintained HIV-1 RNA <200 copies per milliliter by time to loss of virologic response algorithm (intent to treat, noncompleters = failures) with the difference (95% confidence interval) between arms of 1.1% (−6.7% to 8.8%), indicating noninferiority of EFV/FTC/TDF vs. SBR. Similarly, maintenance of HIV-1 RNA <50 copies per milliliter by time to loss of virologic response algorithm was 87% vs. 85% for EFV/FTC/TDF vs. SBR, respectively [difference (95% confidence interval) 2.6% (−5.9% to 11.1%)]. Discontinuation rates were similar (EFV/FTC/TDF 11%, SBR 12%); more discontinuations for adverse events occurred in the EFV/FTC/TDF arm vs. SBR (5% vs. 1%), most commonly for nervous system symptoms. More patients withdrew consent in the SBR arm vs. EFV/FTC/TDF (7% vs. 2%). Estimated glomerular filtration rate (by Modification of Diet in Renal Disease) remained unchanged over 48 weeks in both arms (median change <1 mL·min−1·1.73 m−2). A decrease in fasting triglycerides was observed at 48 weeks in the EFV/FTC/TDF vs. SBR arm (−20 vs. −3.0 mg/dL; P = 0.035). Adherence of ≥96% was reported by visual analog scale in both arms at baseline and at all study visits. Conclusion:Simplification to EFV/FTC/TDF maintained high and comparable rates of virologic suppression vs. SBR through 48 weeks.


Circulation-cardiovascular Interventions | 2010

Impact of Femoral Vascular Closure Devices and Antithrombotic Therapy on Access Site Bleeding in Acute Coronary Syndromes The Acute Catheterization and Urgent Intervention Triage Strategy (ACUITY) Trial

Timothy A. Sanborn; Ramin Ebrahimi; Steven V. Manoukian; Brent T. McLaurin; David A. Cox; Frederick Feit; Martial Hamon; Roxana Mehran; Gregg W. Stone

Background—The Acute Catheterization and Urgent Intervention Triage Strategy (ACUITY) trial demonstrated that bivalirudin monotherapy significantly reduces major bleeding compared with heparin (unfractionated or enoxaparin) or bivalirudin plus a glycoprotein IIb/IIIa inhibitor in acute coronary syndromes. Whether vascular closure devices (VCD) impact these results is unknown. Therefore, this study sought to determine whether VCD impact major access site bleeding (ASB) in patients with acute coronary syndromes undergoing early invasive management by the femoral approach. Methods and Results—Major ASB in ACUITY was defined as ASB requiring interventional or surgical correction, hematoma ≥5 cm at the access site, retroperitoneal bleeding, or hemoglobin drop ≥3 g/dL with ecchymosis or hematoma <5 cm, oozing blood, or prolonged bleeding (>30 minutes) at the access site. Stepwise logistical regression was performed to identify the independent determinants of ASB. Of 11 621 patients undergoing angiography with or without percutaneous coronary intervention by the femoral approach, 4307 (37.1%) received a VCD and 7314 (62.9%) did not. Rates of major ASB were lower with VCD compared with no VCD (2.5% versus 3.3%, relative risk, 0.76; 95% CI, 0.61 to 0.94; P=0.01) and were lowest in patients treated with bivalirudin monotherapy and a VCD (0.7%). Stepwise logistic regression revealed that a VCD (odds ratio, 0.78; 95% CI, 0.61 to 0.99; P=0.04) and bivalirudin monotherapy (odds ratio, 0.35; 95% CI, 0.25 to 0.49; P<0.0001) were both independent determinates of freedom from major ASB. Conclusion—In patients with acute coronary syndromes undergoing an early invasive management strategy by the femoral approach, the use of a VCD, bivalirudin monotherapy, or both minimizes rates of major ASB. Clinical Trial Registration—URL: http://www.clinicaltrials.gov. Unique Identifier: NCT00093158.


Acc Current Journal Review | 2003

Bivalirudin and Provisional Glycoprotein IIb/IIIa Blockade Compared With Heparin and Planned Glycoprotein IIb/IIIa Blockade During Percutaneous Coronary Intervention

A. Michael Lincoff; John A. Bittl; Robert A. Harrington; Frederick Feit; Neal S. Kleiman; J. Daniel Jackman; Ian J. Sarembock; David J. Cohen; Douglas Spriggs; Ramin Ebrahimi; Gadi Keren; Jeffrey Carr; Eric A. Cohen; Amadeo Betriu; Walter Desmet; Wolfgang Rutsch; Robert G. Wilcox; Pim J. de Feyter; Alec Vahanian; Eric J. Topol

A. Michael Lincoff, MD John A. Bittl, MD Robert A. Harrington, MD Frederick Feit, MD Neal S. Kleiman, MD J. Daniel Jackman, MD Ian J. Sarembock, MD David J. Cohen, MD Douglas Spriggs, MD Ramin Ebrahimi, MD Gadi Keren, MD Jeffrey Carr, MD Eric A. Cohen, MD Amadeo Betriu, MD Walter Desmet, MD Dean J. Kereiakes, MD Wolfgang Rutsch, MD Robert G. Wilcox, MD Pim J. de Feyter, MD Alec Vahanian, MD Eric J. Topol, MD for the REPLACE-2 Investigators


AIDS | 2014

Simplification to rilpivirine/emtricitabine/tenofovir disoproxil fumarate from ritonavir-boosted protease inhibitor antiretroviral therapy in a randomized trial of HIV-1 RNA-suppressed participants.

Frank J. Palella; Martin Fisher; Pablo Tebas; Brian Gazzard; Peter Ruane; Jan van Lunzen; David Shamblaw; Jason Flamm; Ramin Ebrahimi; Danielle Porter; Kirsten L. White; Jason Hindman; Elizabeth Elbert; Shampa De-Oertel; Todd Fralich

Objective:To evaluate the efficacy and safety of antiretroviral simplification from a ritonavir-boosted protease inhibitor-based regimen [protease inhibitor+RTV+two nucleos(t)ide reverse transcriptase inhibitors (NRTIs); ≥6 months of exposure prior to study entry with no prior treatment failure] to the single-tablet regimen (STR) rilpivirine/emtricitabine/tenofovir disoproxil fumarate (RPV/FTC/TDF) in virologically suppressed, HIV-1-infected participants. Design:Phase 3b, randomized, open-label, international, 48-week switch study. Methods:Participants were randomized 2 : 1 to switch to RPV/FTC/TDF immediately or stay on their baseline protease inhibitor+RTV+2NRTIs regimen with a delayed switch to RPV/FTC/TDF at week 24. The primary endpoint was noninferiority (12% margin) of RPV/FTC/TDF compared with protease inhibitor+RTV+ two NRTIs in maintaining plasma HIV-1 RNA less than 50 copies/ml at week 24 by Snapshot analysis. Results:A total of 476 participants were randomized and received at least one dose of study drug. Demographics and baseline characteristics were similar between arms. The primary objective of noninferiority at week 24 was met: HIV-1 RNA less than 50 copies/ml by Snapshot analysis, 93.7% of RPV/FTC/TDF versus 89.9% of protease inhibitor+RTV+ two NRTIs (difference 3.8%, 95% confidence interval −1.6 to 9.1%). Through week 48, 89.3% of participants in the immediate switch group maintained virologic suppression. High rates of suppression were maintained with RPV/FTC/TDF regardless of participants pre-antiretroviral HIV-1 RNA level. Overall development of resistance mutations after switching to RPV/FTC/TDF was low. Decreases in total cholesterol, low-density lipoprotein (LDL), and triglycerides were significantly greater among RPV/FTC/TDF recipients than those in the protease inhibitor+RTV+ two NRTIs group. Conclusion:Switching to the STR RPV/FTC/TDF from an RTV-boosted protease inhibitor regimen in virologically suppressed, HIV-1-infected participants maintained virologic suppression with a low risk of virologic failure, while improving total cholesterol, LDL, and triglycerides.


Annals of Emergency Medicine | 2009

Clevidipine, an Intravenous Dihydropyridine Calcium Channel Blocker, Is Safe and Effective for the Treatment of Patients With Acute Severe Hypertension

Charles V. Pollack; Joseph Varon; Norman Garrison; Ramin Ebrahimi; Lala Dunbar; W. Frank Peacock

STUDY OBJECTIVE We assess the safety and efficacy of intravenous clevidipine for treating patients with acute severe increase in blood pressure by using prespecified, non-weight-based titration dosing, with continuous maintenance infusion for 18 hours or longer. METHODS Prospective, open-label, single-arm evaluation of patients aged 18 years or older and presenting in the emergency department or ICU with severe hypertension (systolic blood pressure >180 mm Hg and/or diastolic blood pressure >115 mm Hg) and treated with clevidipine to achieve a predetermined, patient-specific systolic blood pressure target range. Clevidipine was initiated at 2 mg per hour and titrated as needed in doubling increments every 3 minutes to a maximum of 32 mg per hour, during 30 minutes, and then continued for a total duration of 18 to 96 hours. RESULTS Study patients commonly presented with both acute hypertension and end-organ injury; 81% (102/126) had demonstrable end-organ injury at baseline. Within 30 minutes of starting clevidipine, 88.9% (104/117) of patients achieved target range. Median time to target range was 10.9 minutes. No concomitant intravenous antihypertensives were needed in 92.3% (108/117) of patients receiving 18 hours or more of clevidipine infusion. Clevidipine was well tolerated with successful transition to oral antihypertensive therapy after infusion to a defined blood pressure target in 91.3% (115/126) of patients. CONCLUSION Clevidipine, dosed in a non-weight-based manner, was safe and effective in a cohort of patients with severe hypertension at a starting dose of 2 mg per hour, followed by simple titration during 18 hours or more of continuous infusion. Patients were effectively managed via simple blood pressure cuff monitoring throughout.


Circulation-cardiovascular Interventions | 2010

Impact of Femoral Vascular Closure Devices and Antithrombotic Therapy on Access Site Bleeding in Acute Coronary Syndromes

Timothy A. Sanborn; Ramin Ebrahimi; Steven V. Manoukian; Brent T. McLaurin; David A. Cox; Frederick Feit; Martial Hamon; Roxana Mehran; Gregg W. Stone

Background—The Acute Catheterization and Urgent Intervention Triage Strategy (ACUITY) trial demonstrated that bivalirudin monotherapy significantly reduces major bleeding compared with heparin (unfractionated or enoxaparin) or bivalirudin plus a glycoprotein IIb/IIIa inhibitor in acute coronary syndromes. Whether vascular closure devices (VCD) impact these results is unknown. Therefore, this study sought to determine whether VCD impact major access site bleeding (ASB) in patients with acute coronary syndromes undergoing early invasive management by the femoral approach. Methods and Results—Major ASB in ACUITY was defined as ASB requiring interventional or surgical correction, hematoma ≥5 cm at the access site, retroperitoneal bleeding, or hemoglobin drop ≥3 g/dL with ecchymosis or hematoma <5 cm, oozing blood, or prolonged bleeding (>30 minutes) at the access site. Stepwise logistical regression was performed to identify the independent determinants of ASB. Of 11 621 patients undergoing angiography with or without percutaneous coronary intervention by the femoral approach, 4307 (37.1%) received a VCD and 7314 (62.9%) did not. Rates of major ASB were lower with VCD compared with no VCD (2.5% versus 3.3%, relative risk, 0.76; 95% CI, 0.61 to 0.94; P=0.01) and were lowest in patients treated with bivalirudin monotherapy and a VCD (0.7%). Stepwise logistic regression revealed that a VCD (odds ratio, 0.78; 95% CI, 0.61 to 0.99; P=0.04) and bivalirudin monotherapy (odds ratio, 0.35; 95% CI, 0.25 to 0.49; P<0.0001) were both independent determinates of freedom from major ASB. Conclusion—In patients with acute coronary syndromes undergoing an early invasive management strategy by the femoral approach, the use of a VCD, bivalirudin monotherapy, or both minimizes rates of major ASB. Clinical Trial Registration—URL: http://www.clinicaltrials.gov. Unique Identifier: NCT00093158.


American Journal of Cardiology | 2011

Mortality incidence of patients with non-obstructive coronary artery disease diagnosed by computed tomography angiography.

Naser Ahmadi; Vahid Nabavi; Fereshteh Hajsadeghi; Ferdinand Flores; William J. French; Song S. Mao; David M. Shavelle; Ramin Ebrahimi; Matthew J. Budoff

It was previously reported that event-free survival rates of symptomatic patients with coronary artery disease (CAD) diagnosed by computed tomographic angiography decreased incrementally from normal coronary arteries to obstructive CAD. The aim of this study was to investigate the clinical outcomes of symptomatic patients with nonobstructive CAD with luminal stenoses of 1% to 49% on the basis of coronary plaque morphology in an outpatient setting. Among 3,499 consecutive symptomatic subjects who underwent computed tomographic angiography, 1,102 subjects with nonobstructive CAD (mean age 59 ± 14 years, 69.9% men) were prospectively followed for a mean of 78 ± 12 months. Coronary plaques were defined as noncalcified, mixed, and calcified per patient. Multivariate Cox proportional-hazards models were developed to predict all-cause mortality. The death rate of patients with nonobstructive CAD was 3.1% (34 deaths). The death rate increased incrementally from calcified plaque (1.4%) to mixed plaque (3.3%) to noncalcified plaque (9.6%), as well as from single- to triple-vessel disease (p <0.001). In subjects with mixed or calcified plaques, the death rate increased with the severity of coronary artery calcium from 1 to 9 to ≥ 400. The risk-adjusted hazard ratios of all-cause mortality in patients with nonobstructive CAD were 3.2 (95% confidence interval 1.3 to 8.0, p = 0.001) for mixed plaques and 7.4 (95% confidence interval 2.7 to 20.1, p = 0.0001) for noncalcified plaques compared with calcified plaques. The areas under the receiver-operating characteristic curve to predict all-cause mortality were 0.75 for mixed and 0.86 for noncalcified coronary lesions. In conclusion, this study demonstrates that the presence of noncalcified and mixed coronary plaques provided incremental value in predicting all-cause mortality in symptomatic subjects with nonobstructive CAD independent of age, gender, and conventional risk factors.

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Naser Ahmadi

University of California

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Matthew J. Budoff

Los Angeles Biomedical Research Institute

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Vahid Nabavi

Los Angeles Biomedical Research Institute

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Gregg W. Stone

Columbia University Medical Center

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Ferdinand Flores

Los Angeles Biomedical Research Institute

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Steven V. Manoukian

Hospital Corporation of America

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