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Mauricio G Cohen

Publications and source records attributed to Mauricio G Cohen.

18 recordsLinked to original sources
PubMed2006

Aortic counterpulsation: a review of the hemodynamic effects and indications for use.

In the ever evolving field of cardiovascular medicine and coronary intervention, the intra-aortic balloon pump (IABP) is a mature technology, which still plays an important role. The balloon pump invasively supports patient hemodynamics by augmenting diastolic perfusion and increasing diastolic blood pressure, thereby increasing coronary perfusion and reducing afterload. Its efficacy has been demonstrated in a multitude of clinical situations, including acute coronary syndromes, high-risk coronary interventions, cardiogenic shock, and cardiovascular surgery. The potential complications of aortic counterpulsation are serious, although much lower than once feared. With proper patient selection, insertion technique, and management, the IABP is a powerful tool to assist in the treatment of patients with cardiovascular disease. This article will review the hemodynamics, indications, and complications associated with its use.

Angina, Unstable↗
PubMed2006

Mechanical thrombectomy options in complex percutaneous coronary interventions.

Percutaneous coronary interventions (PCI) of thrombus-containing lesions are associated with an increased risk of acute complications and poorer long term vessel patency. Dealing with these vessels provides many technical challenges, especially with the significant risk of coronary no reflow and distal embolization. Pharmacological strategies, including intravenous and intracoronary glycoprotein IIbIIIa inhibitors reduce intracoronary thrombus propagation, improve TIMI flow and are associated with a reduction in adverse event rates. Mechanical strategies (particularly embolic protection and thrombectomy catheters) help to improve coronary blood flow and myocardial perfusion. However, their impact on clinical outcomes is less clear. The use of embolic protection devices is associated with better perfusion, blood flow, and clinical outcomes among patients undergoing saphenous vein graft (SVG) PCI. However, the role for these devices in primary PCI and native coronary artery interventions is uncertain. This study examines the current approaches to manage thrombotic lesions during PCI and reviews the evidence in support of the different mechanical thrombectomy options that are available to the interventional cardiologist.

Angioplasty, Balloon, Coronary↗
PubMed2006

Clinical characteristics, process of care, and outcomes of Hispanic patients presenting with non-ST-segment elevation acute coronary syndromes: results from Can Rapid risk stratification of Unstable angina patients Suppress ADverse outcomes with Early implementation of the ACC/AHA Guidelines (CRUSADE).

BACKGROUND: Data regarding the management of non-ST-segment elevation acute coronary syndromes (NSTE ACS) in Hispanic patients, the largest and fastest-growing minority in the United States, are scarce. METHODS: We sought to describe the clinical characteristics, process of care, and outcomes of Hispanics presenting with NSTE ACS at US hospitals. We compared baseline characteristics, resource use, and inhospital mortality among 3936 Hispanics and 90280 non-Hispanic whites with NSTE ACS from the CRUSADE Quality Improvement Initiative. RESULTS: The regional distribution of Hispanics in CRUSADE paralleled that in the US Census. Hispanics were younger (65 vs 70 years, P < .0001) and had less hyperlipidemia (45.4% vs 49.0%, P < .0001) but were more likely to be hypertensive (72.2% vs 67.9%, P < .0001) and diabetic (46.5% vs 30.9%, P < .0001). Hispanics were also more likely to be uninsured (12.5% vs 5.1%, P < .001). During hospitalization, Hispanics were more often managed conservatively, undergoing stress tests more frequently (13.0% vs 10.1%, P < .0001), with less use of cardiac catheterization within 48 hours (48.7% vs 55.5%, P < .0001) or percutaneous coronary intervention (39.6% vs 46.4%, P < .0001) at any time. Hispanics received similar discharge treatments but were less frequently referred for cardiac rehabilitation (38.5% vs 49.2%, P < .0001). Adjusted inhospital mortality was similar in both groups (odds ratio 0.87, 95% CI 0.72-1.05). CONCLUSIONS: Although hispanics have a different risk factor profile and are treated less aggressively during hospitalization when they present with NSTE ACS, these treatment differences do not appear to affect inhospital outcomes. Further research is warranted to explore the long-term consequences of these findings.

Aged↗
PubMed2006

Regional outcomes after admission for high-risk non-ST-segment elevation acute coronary syndromes.

PURPOSE: An analysis of reginal variation across the United States in the treatment and outcomes of patients with non-ST-segment elevation acute coronary syndromes (NSTE ACS) has not been previously performed. SUBJECTS AND METHODS: We assessed contemporary practice and outcomes in 56,466 high-risk patients with NSTE ACS (positive cardiac markers and/or ischemic ST-segment changes) admitted to 310 hospitals across four defined regions in the United States from January 1, 2001, to September 30, 2003. Patient clinical characteristics, acute (<24 hours) and discharge medications, in-hospital procedures, and in-hospital case-fatality rates were evaluated. RESULTS: Statistically significant but clinically small differences in baseline characteristics including age, gender, rates of diabetes, hypertension, and smoking, as well as medical treatment, including a greater than 5% variation in acute use of beta-blockers, clopidogrel, and statins use, were noted across regions. Adjusted rates of revascularization were similar across regions. Overall in-hospital case-fatality rate was 4.1%, with the highest rates in the Midwest (4.6%) and the lowest in the Northeast (3.5%). Adjusted odds ratios (OR) (95% confidence interval [CI] for death were significantly higher in the Midwest (OR 1.42, CI 1.19-1.70), West (OR 1.40 CI 1.05-1.87), and South (OR 1.33, CI 1.08-1.62), compared with the Northeast. CONCLUSIONS: Management of high-risk patients with NSTE ACS is relatively uniform across the United States. However, in-hospital case-fatality rates vary significantly by region, and the differences are not explained by adjustment for standard clinical variables.

Acute Disease↗
PubMed2005

Extent of ST-segment depression and cardiac events in non-ST-segment elevation acute coronary syndromes.

AIMS: We sought to determine whether the extent of myocardial ischaemia on the admission electrocardiogram (ECG) has independent predictive value for short-term risk stratification of patients with non-ST-segment elevation acute coronary syndromes (NSTE ACS). Although the presence of ischaemic ECG changes on admission has been shown to predict outcome, the relationship between the extent of ECG changes and the risk of cardiac events is still ill defined. METHODS AND RESULTS: We analysed the admission ECGs of 5192 ACS patients enrolled in the GUSTO-IIb trial, without an ECG indication for thrombolysis. ECG tracings showing one or more of the following were eligible: ST-segment depression >0.5 mm, T-wave inversion >1 mm, and ST-segment elevation >0.5 mm but <1 mm. ECG variables associated with unfavourable 30 day outcomes in a univariable analysis were further assessed in a multivariable logistic regression model including independent clinical predictors. In the multivariable clinical, enzymatic, and ECG model, the sum of ST-segment depression (in millimetres) in all leads was a powerful independent predictor of 30 day death (P<0.0001), with a continuous increase in risk with the extent of ST-segment depression. The sum of ST-segment depression (P<0.0001) and the presence of minimal inferior ST-segment elevation (P<0.0001) or anterior ST-segment elevation (P=0.0182) were also independent predictors of the composite of death and myocardial infarction or reinfarction. The extent of ST-segment depression showed a highly significant correlation with the prevalence of three-vessel (P<0.0001) or left main coronary disease (P<0.0001), and also with the peak levels of creatine kinase (P<0.0001) during the index episode of ACS. CONCLUSION: In patients with NSTE ACS, the sum of ST-segment depression in all ECG leads is a powerful predictor of all-cause mortality at 30 days, independent of clinical variables and correlates with the extent and severity of coronary artery disease. The presence of even minimal (<1 mm) ST-segment elevation in anterior or inferior leads is independently associated with adverse outcomes.

Acute Disease↗
PubMed2005

Racial variations in treatment and outcomes of black and white patients with high-risk non-ST-elevation acute coronary syndromes: insights from CRUSADE (Can Rapid Risk Stratification of Unstable Angina Patients Suppress Adverse Outcomes With Early Implementation of the ACC/AHA Guidelines?).

BACKGROUND: Black patients with acute myocardial infarction are less likely than whites to receive coronary interventions. It is unknown whether racial disparities exist for other treatments for non-ST-segment elevation acute coronary syndromes (NSTE ACS) and how different treatments affect outcomes. METHODS AND RESULTS: Using data from 400 US hospitals participating in the CRUSADE (Can Rapid Risk Stratification of Unstable Angina Patients Suppress Adverse Outcomes with Early Implementation of the ACC/AHA Guidelines?) National Quality Improvement Initiative, we identified black and white patients with high-risk NSTE ACS (positive cardiac markers and/or ischemic ST-segment changes). After adjustment for demographics and medical comorbidity, we compared the use of therapies recommended by the American College of Cardiology/American Heart Association guidelines for NSTE ACS and outcomes by race. Our study included 37,813 (87.3%) white and 5504 (12.7%) black patients. Black patients were younger; were more likely to have hypertension, diabetes, heart failure, and renal insufficiency; and were less likely to have insurance coverage or primary cardiology care. Black patients had a similar or higher likelihood than whites of receiving older ACS treatments such as aspirin, beta-blockers, or ACE inhibitors but were significantly less likely to receive newer ACS therapies, including acute glycoprotein IIb/IIIa inhibitors, acute and discharge clopidogrel, and statin therapy at discharge. Blacks were also less likely to receive cardiac catheterization, revascularization procedures, or smoking cessation counseling. Acute risk-adjusted outcomes were similar between black and white patients. CONCLUSIONS: Black patients with NSTE ACS were less likely than whites to receive many evidence-based treatments, particularly those that are costly or newer. Longitudinal studies are needed to assess the long-term impact of these treatment disparities on clinical outcomes.

Black or African American↗
PubMed2005

Safety of adjunctive intracoronary thrombolytic therapy during complex percutaneous coronary intervention: initial experience with intracoronary tenecteplase.

Intracoronary thrombus is associated with increased risk of in-laboratory vessel closure, recurrent myocardial infarction (MI), urgent vessel revascularization, and death. There is a lack of consensus on what represents the ideal treatment for patients with thrombotic complications during percutaneous coronary intervention (PCI), but the development of newer thrombolytic agents with increased fibrin specificity and longer half-life provides a potentially useful treatment option. In this study, the safety and efficacy of intracoronary tenecteplase (TNK) was evaluated in 34 patients (22 with acute ST elevation MI, 4 with rescue PCI, 6 with non-ST elevation MI, and 2 during elective PCI) who developed no-reflow, distal embolization, or visible intracoronary thrombus during PCI. The mean age was 57 years, 76% were Caucasian, and there were 14 women and 20 men. Cardiogenic shock was present in seven (21%) patients at baseline. All patients were being treated with aspirin and either unfractionated heparin (33 patients) or bivalrudin. Glycoprotein IIb/IIIa inhibitors were used in 76% of patients. Intracoronary TNK was used at a mean dose of 10.2 +/- 5.2 mg (median, 10 mg; range, 5-25 mg). There was one TIMI major bleeding event and three TIMI minor bleeding events. The mean hematocrit measured the morning following PCI was 35.5% +/- 4.9% in patients receiving TNK and 36.5% +/- 4.4% in a randomly selected sample of 150 consecutive patients undergoing PCI (P = 0.25). In conjunction with mechanical intervention, TNK was successful at dissolving angiographic thrombus and/or improving flow in 91% of patients. In conclusion, intracoronary TNK is safe and well tolerated in patients who develop thrombotic complications during complex PCI.

Angioplasty, Balloon, Coronary↗
PubMed2005

Clinical predictors and characteristics of patients with chronic liver disease and intrapulmonary shunts.

BACKGROUND: Intrapulmonary shunting (IPS) is a well-described phenomenon in chronic liver disease but its significance is not known. HYPOTHESIS: The study was undertaken to enhance our understanding of the characteristics and prevalence of IPS. METHODS: We retrospectively studied 204 consecutive patients with end-stage chronic liver disease who underwent a dobutamine stress echocardiogram, along with a saline contrast bubble study, as part of their pretransplant evaluation. RESULTS: Intrapulmonary shunting of any degree was present in 56.4% of patients. Patients with IPS were more likely to report alcohol use and less likely to have diabetes mellitus. Patients in Child-Pugh classification C were more likely to have IPS than those with classification A or B. The resting room air PaO2 levels were significantly lower in patients with grade 3-4 IPS than in those with grade 1-2. Elevated estimated pulmonary systolic pressure on echocardiography was more prevalent in patients with than in those without IPS. CONCLUSIONS: A majority of patients with end-stage chronic liver disease undergoing transplant evaluation have IPS. There are important baseline differences between patients with and without IPS. The presence of IPS is associated with increased severity of chronic liver disease. Further study is required to define the prognostic significance of IPS and its impact on future liver transplantation.

Adult↗
PubMed2005

A simple prediction rule for significant renal artery stenosis in patients undergoing cardiac catheterization.

BACKGROUND: Renal artery stenosis (RAS) is a potentially reversible cause of hypertension and renal insufficiency and is associated with poor prognosis. METHODS: We aimed to identify simple predictors of significant RAS among patients undergoing coronary angiography. Prospective data were collected on 843 consecutive patients who underwent cardiac catheterization and abdominal aortography. Stenoses > or = 75% were considered significant. Multivariable logistic regression was used to assess the relationship between baseline characteristics and coronary anatomy with significant RAS. A simple risk score was derived from the model. RESULTS: The prevalence of RAS > or = 75% was 11.7%. Independent predictors of significant RAS were older age, higher creatinine levels, peripheral vascular disease, number of cardiovascular drugs, hypertension, female sex, and 3-vessel coronary artery disease or previous coronary artery bypass graft. The concordance index of the model was 0.802. These variables were used to develop a simple predictive score of significant RAS for patients undergoing cardiac catheterization. The prevalence of RAS increased stepwise with increasing score values: 0.6% for a score < or = 5, 1.5% for 6 to 7, 6.1% for 8 to 9, 12.2% for 10 to 11, 18.7% for 12 to 14, 35.7% for 15 to 17, and 62.1% for > or = 18 (P < .001). Approximately one third of the patients had a score > or = 11, which yielded a sensitivity of 76% and a specificity of 71%. CONCLUSIONS: Renal artery stenosis is a relatively common finding among patients referred for coronary angiography. A simple score can predict the presence of significant RAS among patients referred for cardiac catheterization.

Adult↗
PubMed2005

Pulmonary artery catheterization in acute coronary syndromes: insights from the GUSTO IIb and GUSTO III trials.

PURPOSE: To correlate pulmonary artery catheterization (PAC) use and 30-day outcomes and to characterize the use of pulmonary artery catheters among patients with acute coronary syndromes (ACS). SUBJECTS AND METHODS: We retrospectively studied 26437 ACS patients from two large multicenter, international randomized clinical trials. Multivariable and causal inference analyses were applied to adjust for differences in baseline risk. RESULTS: PAC was performed in 735 patients (2.8%), with a median time to insertion of 24 hours. Patients undergoing PAC were older (median, 67 vs. 64 years), more often diabetic (25.7% vs.16.2%), and more likely to present with ST-segment elevation (81.6% vs. 70.2%) or Killip class III or IV (7.9% vs. 1.4%). US patients were 3.8 times more likely than non-US patients to undergo PAC. Patients managed with PAC also underwent more procedures, including percutaneous intervention (40.7% vs. 18.1%), coronary artery bypass grafting (12.5% vs. 7.7%), and endotracheal intubation (29.3% vs. 2.2%). Mortality at 30 days was substantially higher among patients with PAC for both unadjusted (odds ratio [OR] 8.7; 95% confidence interval [CI] 7.3-10.2) and adjusted analyses (OR 6.4; 95% CI 5.4-7.6) in all groups except in patients with cardiogenic shock (OR 0.99; 95% CI 0.80-1.23). CONCLUSIONS: PAC was associated with increased mortality, both before and after adjustment for baseline patient differences and subsequent events that may have led to PAC use, except in patients with cardiogenic shock. The definitive role of PAC in managing patients with ACS is still to be determined.

Acute Disease↗
PubMed2004

Facilitated percutaneous coronary intervention in acute myocardial infarction: attractive concept but difficult to prove!

Facilitated percutaneous coronary intervention (PCI) refers to a strategy of immediate PCI following the administration of pharmacological therapies in acute myocardial infarction. It has evolved primarily from the time delays (due to geography or logistics) in getting acute myocardial infarction patients to the catheterization laboratory and the associated irreversible loss of myocardial muscle that occurs as door-to-balloon time increases. Facilitated PCI provides an opportunity to start treating many of these patients before they reach the catheterization laboratory and provides an ability to open the infarct-related artery before PCI, which is associated with better outcomes for AMI patients. Pharmacological strategies before PCI include: thrombolytic therapy, glycoprotein IIb/IIIa inhibitor alone, or a combination of thrombolytic therapy plus glycoprotein IIb/IIIa inhibitor. Initial results of angiographic studies show better patency with the latter strategy but at the expense of higher bleeding event rates. Ongoing trials are evaluating different combinations of thrombolytic and glycoprotein IIb/IIIa inhibitor therapy.

Angioplasty, Balloon, Coronary↗
PubMed2003

Early reperfusion and late clinical outcomes in patients presenting with acute myocardial infarction randomly assigned to primary percutaneous coronary intervention or streptokinase.

BACKGROUND: Primary percutaneous coronary intervention (PCI) has become an alternative to thrombolytic therapy as a reperfusion strategy for ST-elevation acute myocardial infarction (AMI). METHODS: The main goal of this study was to determine whether PCI and thrombolytic therapy achieve comparable reperfusion rates, as evidenced by ST-segment resolution. Secondary end points included infarct vessel patency rates before hospital discharge and short- and long-term outcomes. Patients with ischemic chest pain with duration < or =12 hours and no contraindication for thrombolytic therapy were included. RESULTS: Between October 1993 and August 1995, 58 patients were randomly assigned to streptokinase (SK) and 54 patients to primary PCI. Baseline clinical characteristics and infarct location were well balanced in both groups. Median age (interquartile range) was 68 (58, 75) years, 29% were women, and 78% of the patients met at least one criterion for "not low risk" AMI (anterior location, age >70 years old, previous MI, systolic blood pressure <100 mm Hg, and/or heart rate >100 bpm). The median time from symptom onset to random assignment was 217 (139, 335) minutes in the PCI group and 210 (145, 334) minutes in the SK group. Median random assignment to balloon time was 82 (55, 100) minutes, and median random assignment to needle time was 15 (10, 26) minutes (P <.0001). TIMI grade 3 flow after primary PCI was obtained in 85% of patients. The proportion of patients with ST-segment resolution > or =50% at 120 minutes was 80% in the PCI group and 50% in the SK group (P =.001). The predischarge angiogram showed the presence of TIMI 3 flow in 96% of patients who received PCI and 65% of patients who received SK (P <.001). A composite of in-hospital death, reinfarction, severe heart failure, stroke, and major bleeding occurred in 15% of patients who received PCI and 21% of patients who received SK (P =.4). At 3 years, freedom from the composite end point of AMI, postdischarge revascularization, and death was 61% in the PCI group and 40% in the SK group (P =.025). CONCLUSIONS: Our study shows that primary PCI, as compared with SK, is associated with more effective ST-segment resolution, higher patency rates in the infarct vessel at 7 days, and more favorable clinical outcomes at 3 years of follow-up.

Aged↗
PubMed2002

Successful percutaneous coronary intervention with stent implantation in anomalous right coronary arteries arising from the left sinus of valsalva: a report of two cases.

Percutaneous coronary intervention (PCI) in an anomalous right coronary artery arising from the left sinus of valsalva can be technically challenging because of difficulty in selectively cannulating the vessel. We present two cases of successful stent implantation in an anomalous right coronary artery arising from the left sinus of valsalva. In both cases, we used an oversized 6 Fr Judkins left guiding catheter, which provided excellent angiographic visualization and guide support for stent delivery.

Aged↗
PubMed2002

Electrocardiographic comparison of myocardial salvage with primary revascularization versus thrombolysis in inferior myocardial infarction.

Primary revascularization (PR) and thrombolytic therapy (TT) reduce infarct size and mortality in patients with ST-segment elevation acute myocardial infarction (AMI). Electrocardiogram methods can determine the extent of myocardial salvage with different AMI therapies by comparing infarct size predicted by initial ST-segment changes and infarct size estimated by later quantitative QRS scores. In a community hospital setting, we used quantitative electrocardiogram methods to estimate infarct size and myocardial salvage associated with TT and PR amongst 50 patients presenting with inferior ST-segment elevation AMI. Baseline and electrocardiogram characteristics did not differ between TT (n = 29) and PR (n = 21) patients. There was no difference in median myocardial salvage (%) between TT vs. PR groups, (38.3% vs. 44.9% respectively, P =.66). Among patients with inferior AMI, myocardial salvage was achieved with both TT and PR therapy and did not differ significantly between reperfusion strategies.

Aged↗