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Dive into the research topics where Howard A. Cohen is active.

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Featured researches published by Howard A. Cohen.


Circulation | 2000

Percutaneous Coronary Intervention in the Current Era Compared With 1985–1986 The National Heart, Lung, and Blood Institute Registries

David O. Williams; Richard Holubkov; Wanlin Yeh; Martial G. Bourassa; Mahdi Al-Bassam; Peter C. Block; Paul Coady; Howard A. Cohen; Michael J. Cowley; Gerald Dorros; David P. Faxon; David R. Holmes; Alice K. Jacobs; Sheryl F. Kelsey; Spencer B. King; Richard K. Myler; James Slater; Vladimir Stanek; Helen Vlachos; Katherine M. Detre

Background—Although refinements have occurred in coronary angioplasty over the past decade, little is known about whether these changes have affected outcomes. Methods and Results—Baseline features and in-hospital and 1-year outcomes of 1559 consecutive patients in the 1997–1998 Dynamic Registry who were having first coronary intervention were compared with 2431 patients in the 1985–1986 National Heart, Lung, and Blood Institute Registry. Compared with patients in the 1985–1986 Registry, Dynamic Registry patients were older (mean age, 62 versus 58 years;P <0.001) and more often female (32.1% versus 25.5%;P <0.001). In the Dynamic Registry, procedures were more often performed for acute myocardial infarction (22.9% versus 9.9%;P <0.001) and treated lesions were more severe (84.5% versus 82.5% diameter reduction;P <0.001), thrombotic (22.1% versus 11.3%;P <0.001) or calcified (29.5% versus 10.8%;P <0.001). Stents were used in 70.5% of Dynamic Registry patients, whereas 1985–1986 patients received balloon angioplasty alone. Procedural success was higher in the Dynamic Registry (92.0% versus 81.8%;P <0.001) and the rate of in-hospital death, myocardial infarction, and emergency coronary bypass surgery combined was lower (4.9% versus 7.9%;P =0.001) than in the 1985–1986 Registry. The 1-year rate for CABG was lower in the Dynamic Registry (6.9% versus 12.6%;P <0.001). Conclusions—Although Dynamic Registry patients had more unstable and complex coronary disease than those in the 1985–1986 Registry, their rate of procedural success was higher whereas rates of complications and subsequent CABG were lower. Results of percutaneous coronary intervention have improved substantially over the past decade.


Journal of the American College of Cardiology | 2011

Clinical Outcomes in Patients Undergoing Percutaneous Closure of Periprosthetic Paravalvular Leaks

Carlos E. Ruiz; Vladimir Jelnin; Itzhak Kronzon; Yuriy Dudiy; Raquel del Valle-Fernández; Bryce Einhorn; Paul T.L. Chiam; Claudia A. Martinez; Rocio Eiros; Gary S. Roubin; Howard A. Cohen

OBJECTIVES The purpose of this study was to evaluate the feasibility and efficacy of the percutaneous device closure of a consecutive series of patients with periprosthetic paravalvular leaks referred to our structural heart disease center with congestive heart failure and hemolytic anemia. BACKGROUND Clinically significant periprosthetic paravalvular leak is an uncommon but serious complication after surgical valve replacement. Percutaneous closure has been utilized as an alternative to surgical repair of this defect in high-risk surgical patients. METHODS This is a retrospective review of 57 percutaneous paravalvular leak closures that were performed in 43 patients (67% male, mean age 69.4 ± 11.7 years) between April 2006 and September 2010. Integrated imaging modalities were used for the evaluation, planning, and guidance of the interventions. RESULTS Closure was successful in 86% of leaks and in 86% of patients. Twenty-eight of 35 patients improved by at least 1 New York Heart Association functional class. The percentage of patients requiring blood transfusions and/or erythropoietin injections post-procedure decreased from 56% to 5%. Clinical success was achieved in 89% of the patients in whom procedure was successful. The survival rates for patients at 6, 12, and 18 months after paravalvular leak closures were 91.9%, 89.2%, and 86.5%, respectively. Freedom from cardiac-related death at 42 months post-procedure was 91.9%. CONCLUSIONS Percutaneous closure of symptomatic paravalvular leaks, facilitated by integrated imaging modalities has a high rate of acute and long-term success and appears to be effective in managing symptoms of heart failure and hemolytic anemia.


American Journal of Cardiology | 2001

Immediate and one-year outcome in patients with coronary bifurcation lesions in the modern era (NHLBI dynamic registry).

Jassim Al Suwaidi; Wanlin Yeh; Howard A. Cohen; Katherine M. Detre; David O. Williams; David R. Holmes

Balloon angioplasty of bifurcation lesions has been associated with lower success and higher complication rates than most other lesion types. The development of alternative strategies such as debulking and stenting, either alone or in combination, are currently used relatively often. The relative role of these newer approaches in improving acute or long-term outcome, however, remains uncertain. Of the total of 2,436 patients treated between July 1997 to February 1998 in the National Heart, Lung, and Blood Institute Dynamic Registry, there were 321 patients (group 1) with bifurcation lesions and 2,115 patients without any bifurcation lesions attempted (group 2). Treatment strategies in terms of major devices used were significantly different between the 2 groups (group 1 vs 2): balloon angioplasty alone (23.1% vs 26.5%), balloon angioplasty and rotational atherectomy (6.9% vs 4.4%), balloon angioplasty and stent (55.8% vs 59.9%), and balloon angioplasty, rotational atherectomy, and stent (10.3% vs 7%) with p <0.01. There were no significant differences between the groups in terms of age, gender, and frequency of prior myocardial infarction (MI) or coronary artery bypass graft surgery (CABG). Complete angiographic success was achieved in only 86% of bifurcation lesions versus 93.5% of nonbifurcation lesions (p <0.001). In-hospital complication rates were increased in patients with bifurcation lesions compared with the nonbifurcation group: MI, 3.7% versus 2.6%; CABG, 2.2% versus 1.1%; side branch occlusion, 7.3% versus 2.3% (p <0.001); and the composite of death, MI, and any CABG, 7.2% versus 5.0%. At 1-year follow-up, major adverse cardiac events were 25% higher in group 1 than in group 2 (32.1% vs 25.7%, p <0.05). We conclude that despite the widespread use of newer percutaneous devices, treatment of bifurcation lesions remains difficult and is associated with decreased success and increased complication rates compared with nonbifurcation lesions.


Catheterization and Cardiovascular Interventions | 2007

Access site hematoma requiring blood transfusion predicts mortality in patients undergoing percutaneous coronary intervention: Data from the National Heart, Lung, and Blood Institute Dynamic Registry

Leonid Yatskar; Faith Selzer; Fredrick Feit; Howard A. Cohen; Alice K. Jacobs; David O. Williams; James Slater

To determine both the etiology of and outcomes associated with access site hematoma requiring transfusion (HRT) in patients undergoing percutaneous coronary intervention (PCI).


American Heart Journal | 2003

Impact of age on procedural and 1-year outcome in percutaneous transluminal coronary angioplasty: A report from the NHLBI Dynamic Registry

Howard A. Cohen; David O. Williams; David R. Holmes; Faith Selzer; Kevin E. Kip; Janet M. Johnston; Richard Holubkov; Sheryl F. Kelsey; Katherine M. Detre

BACKGROUND Older age has been associated with adverse outcomes in patients undergoing percutaneous coronary intervention (PCI). As PCI technology evolves and the US population becomes proportionally older, assessment of PCI in older age groups is essential. METHODS From the National Heart, Lung, and Blood Institute Dynamic Registry, 4620 PCI-treated patients (1997 to 1999) were studied. Differences in clinical presentation, treatment strategy, and inhospital and 1-year outcomes were compared between patient age groups: younger (<65 years, n = 2537); older (65 to 79 years, n = 1776); and elderly (> or =80 years, n = 307). RESULTS Older and elderly patients had more cardiac and comorbid noncardiac conditions and more extensive and complex arteriosclerosis, including stenoses in bypass grafts. Stent use was similar as age increased (72% vs 73% vs 73%), as was the use of IIb/IIIa receptor antagonists (29% vs 26% vs 28%). Rates of successful treatment of all attempted lesions were 93%, 92%, and 89%, respectively. Adjusted relative risks of inhospital death (1.0 vs 2.91 vs 3.64) and myocardial infarction (1.0 vs 1.35 vs 2.57) increased by age group, as did 1-year mortality rates (1.0 vs 1.87 vs 3.02). However, the relative magnitude of excess mortality rates at 1 year was comparable to that observed by age in the US general population. Age was not associated with 1-year risk of myocardial infarction or coronary artery bypass grafting. CONCLUSIONS Although new technologies may allow for treatment of complex disease in older and elderly patients with comorbid disease, the increased procedural risk remains substantial in these patients. After PCI, the long-term relative risk of death is similar to that expected among persons of similar ages in the general population.


Jacc-cardiovascular Interventions | 2011

Clinical Experience With Percutaneous Left Ventricular Transapical Access for Interventions in Structural Heart Defects: A Safe Access and Secure Exit

Vladimir Jelnin; Yuriy Dudiy; Bryce Einhorn; Itzhak Kronzon; Howard A. Cohen; Carlos E. Ruiz

OBJECTIVES This study sought to evaluate the safety of percutaneous direct left ventricular access for interventional procedures. BACKGROUND Experience with percutaneous access of the left ventricle (LV) for interventional procedures has been limited and associated with a high percentage of major complications. We report our clinical experience with percutaneous direct LV access for interventional procedures. METHODS Between March 2008 and December 2010, there were 32 percutaneous transapical punctures in 28 consecutive patients (16 males, mean age 68.2 ± 10.8 years). The delivery sheath sizes ranged from 5- to 12-F. RESULTS All transapical punctures were successfully performed, and safe closure of the access sites was achieved. Total procedural time was 153.6 ± 49.4 min for procedures converted from conventional approaches to a transapical approach, 129.5 ± 29.6 min for the transapical approach with trans-septal rail support, and 109.3 ± 41.4 min for the planned transapical approach. Fluoroscopy time was 61.3 ± 26.1 min, 29.7 ± 20.8 min, and 27.4 ± 21.4 min, respectively. Fluoroscopy time for closure of mitral paravalvular leaks was reduced by 35%, from 42.6 ± 29.9 min to 27.4 ± 15.6 min. Complications were observed in 2 patients (7.1%). CONCLUSIONS With meticulous planning, transapical puncture is safe. The transapical access provides a more direct approach to the LV targets for intervention and leads to a significant decrease in the procedural and fluoroscopy times. Device closure of the direct LV access site is a reliable and safe method of hemostasis. Placement of a closure device should be considered if sheaths larger than 5-F are used. Although we used this technique only for paravalvular leak and LV pseudoaneurysm closure, it may have application for other percutaneous structural heart interventions.


Circulation | 1998

Feasibility of Combined Percutaneous Transluminal Angioplasty and Minimally Invasive Direct Coronary Artery Bypass in Patients With Multivessel Coronary Artery Disease

Howard A. Cohen; Marco A. Zenati; A.J. Conrad Smith; Joon S. Lee; Simon Chough; Zubair Jafar; Peter J. Counihan; Mark Izzo; J.E. Burchenal; Arthur M. Feldman; Bartley P. Griffith

BACKGROUND Angioplasty has become an accepted treatment of patients with coronary artery disease and is now commonly used to treat patients with multivessel disease. The major disadvantage of angioplasty has been restenosis requiring repeat interventions with resultant loss of initial cost savings. Compared with the right and the circumflex coronary arteries, the left anterior descending artery (LAD) has been more adversely affected by restenosis. Recently, minimally invasive direct coronary artery bypass (MIDCAB) to the LAD through a small left anterior thoracotomy using the left internal mammary artery has been performed in some centers with excellent early results and with reduced costs compared with standard bypass surgery. METHODS AND RESULTS We retrospectively reviewed the first 31 consecutive patients treated in our institution with integrated coronary revascularization (ICR): MIDCAB to the LAD combined with PTCA of the other diseased vessels in patients with multivessel disease. Postoperative angiography in 84% of patients revealed a patent anastomosis and normal flow in the graft and bypassed vessel. Thirty-eight (97%) of 39 vessels were successfully treated percutaneously. At a mean follow-up of 7 months, all patients are currently asymptomatic. There have been 2 adverse clinical events, both related to angioplasty and not to MIDCAB. The average length of stay at the hospital after MIDCAB was 2.79+/-1.05 days. CONCLUSIONS These preliminary results with ICR are encouraging and suggest that a randomized, prospective clinical trial comparing ICR with standard coronary artery bypass surgery for the revascularization of symptomatic patients with multivessel disease involving the LAD is warranted.


Circulation | 2003

Modeling and Risk Prediction in the Current Era of Interventional Cardiology A Report From the National Heart, Lung, and Blood Institute Dynamic Registry

David R. Holmes; Faith Selzer; Janet M. Johnston; Sheryl F. Kelsey; Richard Holubkov; Howard A. Cohen; David O. Williams; Katherine M. Detre

Background—Validation of in-hospital mortality models after percutaneous coronary interventions using multicenter data remains limited. Methods and Results—This study evaluated whether multivariable mortality models developed during the pre-stent era by New York State, American College of Cardiology (ACC)–National Cardiovascular Data Registry, Northern New England Cooperative Group, Cleveland Clinic Foundation, and the University of Michigan are relevant in patients undergoing percutaneous coronary intervention in the 1997 to 1999 National Heart, Lung, and Blood Institute Dynamic Registry. Of 4448 Dynamic Registry patients, 73% received ≥1 stent and 28% received a IIB/IIIA receptor inhibitor. In-hospital mortality occurred in 64 patients (1.4%). The New York state model predicted mortality in 69 patients (1.5%; 95% confidence bounds [CI], 0.89% to 1.70%); Northern New England predicted mortality in 60 patients (1.3%; 95% CI, 1.0% to 1.7%); and Cleveland Clinic predicted mortality in 76 patients (1.7%; 95% CI, 1.3% to 2.1%). Among high-risk subgroups, with these 3 models, observed and predicted in-hospital mortality rates in general were not different. The other 2 models yielded different results. The University of Michigan predicted fewer deaths (n=47; 1.1%; 95% CI, 0.7% to 1.3%), and the ACC Registry model predicted 603 deaths (13.5%; 95% CI, 12.6% to 14.4%). Using the ACC Registry model, predicted mortality was higher than observed in each subgroup. Conclusions—Application of 5 mortality risk models developed from different data sets to patients undergoing percutaneous coronary intervention in the Dynamic Registry predicted, in 3 models, mortality rates that were not significantly different than those observed. In both high and low risk subgroups, the University of Michigan slightly underpredicted mortality, and the ACC Registry predicted significantly higher mortality than that observed.


American Journal of Cardiology | 2001

Changes in the practice of percutaneous coronary intervention: a comparison of enrollment waves in the national heart, lung, and blood institute (NHLBI) dynamic registry

Warren K. Laskey; David O. Williams; Helen Vlachos; Howard A. Cohen; David R. Holmes; Spencer B. King; Sheryl F. Kelsey; James Slater; David P. Faxon; Mahdi Al-Bassam; Elizabeth H. Block; Katherine M. Detre

The National Heart, Lung, and Blood Institute Dynamic Registry includes 15 clinical sites in wave 1, and 16 sites in wave 2 as well as a data-coordinating center. The first wave of enrollment began in July 1997 and was completed in February 1998. The second wave began in February 1999 and ended in June 1999. There were a total of 2,526 patients in wave 1 and 2,109 patients in wave 2. Comprehensive pre-, intra-, and postprocedure (in-hospital) data were analyzed for changes between recruitment waves. Patients in wave 2 were more frequently nonwhite (p < or = 0.001), hypertensive by history (p < or = 0.001), had more significant noncardiac comorbidity (p < or = 0.01), and had more frequently undergone prior percutaneous coronary intervention (p < 0.05). Patients in wave 2 underwent percutaneous coronary intervention in a setting of acute coronary syndromes more frequently than wave 1 patients (p < or = 0.001). However, most interventions in both waves were performed on 1 vessel, irrespective of the extent of disease. Attempted lesions in wave 2 were longer (p < or = 0.001), less frequently totally occluded (p < or = 0.001), and more frequently in vessels with a prior stent (p < or = 0.01). Using the American Heart Association/American College of Cardiology lesion classification scheme, attempted lesions in wave 2 were less complex than those in wave 1 (p < or = 0.001). Stent use increased significantly from wave 1 (67%) to wave 2 (79%, p < or = 0.001) as did the use of platelet glycoprotein IIb/IIIa antagonists (wave 1, 24%; wave 2, 32%: p < 0.001). Procedural outcomes (angiographic success without major in-hospital adverse events) were excellent in both waves 1 (94.6%) and 2 (95.6%) and were not significantly different. However, the frequency of significant procedural coronary dissection and in- and out-of-laboratory abrupt closure were significantly less in wave 2 (p < or = 0.001) Discharge medications were more likely to include angiotensin-converting enzyme inhibitors, beta-adrenergic blocking agents, and hypolipidemic treatment in wave 2 than in wave 1 (p < or = 0.001). These data indicate a continuing aggressive approach to patient care over the time interval analyzed. Although overall procedural outcomes are excellent, procedural safety has been further enhanced. There is also a growing awareness of the importance of secondary prevention among interventional cardiologists.


American Journal of Cardiology | 1999

Assessment of left internal mammary artery graft patency and flow reserve after minimally invasive direct coronary artery bypass

William E. Katz; Marco A. Zenati; William A. Mandarino; Howard A. Cohen; John Gorcsan

Despite its merits, minimally invasive direct coronary artery bypass surgery (MIDCAB) has been criticized for variable left internal mammary artery (LIMA) graft patency rates, prompting the frequent use of postoperative LIMA angiography. Noninvasive transthoracic Doppler interrogation of LIMA grafts has recently been shown to have utility for assessing patency and flow reserve after conventional bypass surgery, but data after MIDCAB has been limited. The objective of this study was to assess LIMA graft anatomy and physiology in 54 patients after MIDCAB using angiography and noninvasive LIMA Doppler imaging. The right internal mammary artery (RIMA) was studied as a control. LIMA flow reserve in response to adenosine was evaluated in a subgroup of 18 randomly chosen patients with patent grafts. LIMA angiographic patency was 93%. Forty-four patients (81%) had obtainable LIMA Doppler data. Patent grafts had a diastolic dominant flow pattern with a peak diastolic/systolic velocity ratio of 1.3 +/- 0.6 and a percent diastolic time-velocity integral (TVI) of 70 +/- 11%. These data were significantly different than the RIMA control values of 0.2 +/- 0.1 and 30 +/- 10%, respectively (p <0.05). Occluded grafts had absent flow or a systolic dominant pattern. Adenosine-induced increases in LIMA peak diastolic velocity from 48 +/- 20 to 105 +/-28 cm/s (p <0.05 vs baseline) and diastolic TVI from 21 +/- 10 to 37 +/- 19 cm (p <0.05 vs baseline), yielding adenosine/baseline ratios of 2.4 +/- 0.9 and 2.0 +/- 0.7, respectively, which was consistent with normal flow reserve. The diastolic flow velocity reserve response was inversely related to baseline diastolic flow (r = -0.69). In conclusion, MIDCAB can be associated with a high rate of LIMA potency and favorable physiologic Doppler flow patterns. Correlation of these findings to long-term patient outcome after MIDCAB is warranted.

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David O. Williams

Brigham and Women's Hospital

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Faith Selzer

University of Pittsburgh

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Carlos E. Ruiz

University of Illinois at Chicago

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