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George A Stouffer

Publications and source records attributed to George A Stouffer.

At least 19 recordsLinked to original sources
PubMed2026

2025 Acute Coronary Syndrome Guideline: Missing the Boat on CYP2C19 Genotyping.

The 2025 American College of Cardiology/American Heart Association/American College of Emergency Physicians/National Association of Emergency Medical Services Physicians/Society for Cardiovascular Angiography & Interventions acute coronary syndrome guideline focuses on strategies to reduce bleeding risk with antiplatelet therapy yet lacks any recommendation related to CYP2C19 genotyping. The impact of CYP2C19 loss-of-function alleles on the effectiveness of clopidogrel is well documented, and although prasugrel and ticagrelor more effectively reduce the risk for atherothrombotic events compared with clopidogrel in patients with a CYP2C19 loss-of-function allele, clopidogrel reduces bleeding risk without an increase in atherothrombotic events compared with prasugrel or ticagrelor in those without a loss-of-function allele. Accordingly, an American Heart Association Scientific Statement supports CYP2C19 genetic testing before oral P2Y12 inhibitors are prescribed. This commentary summarizes the evidence in support of CYP2C19-guided P2Y12 inhibitor selection in the context of other 2025 acute coronary syndrome guideline recommendations and urges future guidelines to incorporate recommendations for CYP2C19 genotyping, especially for those at high bleeding risk.

Humans↗
PubMed2025

Impact of Race on Profiles of Platelet Reactivity and Clinical Outcomes in Clopidogrel-Treated Participants.

Black individuals undergoing percutaneous coronary intervention (PCI) experience higher rates of major adverse cardiovascular events (MACE) than non-Black individuals. This study assessed the racial differences in platelet reactivity and clinical outcomes among clopidogrel-treated participants. Two cohorts were analyzed. The pharmacodynamic (PD) cohort involved patients with atherosclerotic cardiovascular disease on maintenance clopidogrel therapy undergoing platelet function testing. The primary outcome was high platelet reactivity (HPR, i.e., P2Y12 reaction unit [PRU]&#x2009;>&#x2009;208). The PCI cohort included participants undergoing PCI on clopidogrel-based dual antiplatelet therapy. The primary outcome was 1-year MACE, defined as the composite of cardiovascular death, myocardial infarction (MI), ischemic stroke, or stent thrombosis. Data on clinically significant bleeding and CYP2C19 genotyping alleles were collected. The PD and PCI cohorts included 728 (32.1% Black) and 2,770 (20.5% Black) participants, respectively. Black participants had higher PRU levels (184 [IQR 128-234] vs. 144 [IQR 88-195]; P&#x2009;<&#x2009;0.001) and higher prevalence of HPR (39.3% vs. 20.6%; P&#x2009;<&#x2009;0.001). Independent predictors of HPR included Black race, hemoglobin levels, and presence of CYP2C19 loss-of-function allele. In the PCI cohort, Black participants had a higher risk of MACE (HR 1.47; 95% CI 1.02-2.11; P&#x2009;=&#x2009;0.037), primarily driven by MI (HR 1.71; 95% CI 1.09-2.67; P&#x2009;=&#x2009;0.019), with no significant difference in clinically significant bleeding (HR 1.08; 95% CI 0.65-1.80; P&#x2009;=&#x2009;0.768). Black participants on clopidogrel exhibit higher platelet reactivity, increased rates of HPR, and an elevated risk of MACE within 1 year after PCI, without significant differences in bleeding compared to non-Black participants.

Aged↗
PubMed2006

Comparison of bare metal stents versus drug-eluting stents on clinical decision making in patients with previous percutaneous coronary intervention admitted for suspected acute coronary syndrome.

To determine whether the decreased rate of restenosis observed with drug-eluting stents (DES) has changed the treatment of patients with recurrent symptoms after stent placement, we compared patients hospitalized with presumed cardiac symptoms within 1 year after placement of either a DES or a bare metal stent (BMS). In this retrospective, single-center study, cases were identified from consecutive patients who received a DES from March 2003 to July 2004 or a BMS from August 2001 to June 2002. No differences were noted in the rate of hospitalization, hospitalization for presumed cardiac symptoms, use of coronary angiography in patients hospitalized for presumed cardiac symptoms, or average interval to hospitalization. In contrast, restenosis and the need for additional revascularization procedures were higher in the BMS group. The primary indication for additional revascularization was restenosis in the BMS group and progression of coronary artery disease in the DES group. In the DES group, the need for revascularization was significantly higher in patients with multi- versus single-vessel coronary artery disease (26% vs 7%, p < 0.05). In conclusion, the rate of hospitalization and use of coronary angiography in patients with recurrent symptoms were similar in patients who received a BMS or DES, despite the decreased rates of restenosis and additional revascularization procedures observed with DESs.

Acute Disease↗
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

Timing of surgery in aortic stenosis.

Aortic valve stenosis (AVS) usually results from three distinct processes (degenerative-calcific, rheumatic, and congenital), with a final common pathway of significant aortic outflow tract obstruction. The stenotic lesion tends to progress slowly, but once symptoms develop clinical deterioration can ensue rapidly. Chest pain, dyspnea, and syncope are the most common symptoms of significant AVS. Detection of symptoms, subtle or obvious, is critical to the management of AVS because their presence portends a worse overall prognosis and is an indication for intervention. There are several special clinical scenarios that require added consideration, including individuals with concomitant coronary artery disease, the presence of a relatively small transvalvular pressure gradient in the setting of low cardiac output (so-called low-gradient AVS), and elderly with severe AVS. Surgical aortic valve replacement (AVR) is the mainstay treatment for relief of obstruction in patients with symptomatic AVS. Percutaneous balloon valvuloplasty is reserved for the small minority of patients who are not surgical candidates and is associated with a high restenosis rate. Percutaneous AVR is a new technology that is being tested in a few select centers on patients who are not operative candidates.

Journal Article↗
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

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

Diagnosis and treatment of non-hemodynamically significant coronary heart disease: where to start?

In the U.S. and all industrialized countries, more deaths result from heart attack and stroke than from any other cause. Increasingly it is proposed that many cardiac events occur following the rupture of minor, non-hemodynamically significant atherosclerotic plaque. Indeed many policy makers and some physicians have questioned the importance of traditional screening and treatment strategies for hemodynamically significant coronary artery lesions. As an alternative, it has been suggested that screening and treatment approaches should be guided by emerging data that support the predictive value of measures of inflammation, such as high sensitivity C-reactive protein, or of genetic markers. Our goal is review the biology of acute coronary events and the results of population-based studies and, in this light, consider the usefulness of the current "state-of-the-art" methods for diagnosing coronary heart disease.

Coronary Disease↗
PubMed2004

Effect of multielement intravascular ultrasound on the anticoagulant potency of enoxaparin.

Two patients, treated with enoxaparin and eptifibatide, developed significant guide catheter-associated thrombus while undergoing intravascular ultrasound (IVUS). Using an ex vivo assay, we found that activation of a multielement IVUS catheter resulted in a decrease in anti-Xa activity and a decrease in clot formation time. This effect occurred rapidly and repeatedly after activation of the IVUS catheter.

Aged↗
PubMed2004

Percutaneous coronary intervention in a patient with immune thrombocytopenia purpura.

The appropriate regimen of platelet inhibitors that should be used in patients with immune thrombocytopenia purpura (ITP; formerly called idiopathic thrombocytopenic purpura) who are undergoing percutaneous coronary intervention is unclear. We report the case of a patient with ITP who underwent two separate coronary interventions. The first involved the use of aspirin and a cutting balloon to treat obstructive disease of the left circumflex. When the patient presented with restenosis, he received eptifibatide, clopidogrel, and an intracoronary stent. He is currently 16 months removed from his second procedure and remains physically active without any anginal symptoms. Percutaneous revascularization in patients with ITP remains a challenge and this therapeutic approach, while ultimately successful in the patient, requires further validation.

Aged↗
PubMed2004

Timing of aortic valve surgery in chronic aortic stenosis and regurgitation.

The correct timing of aortic valve replacement in chronic aortic stenosis or regurgitation is a very important and sometimes difficult task for physicians caring for patients with aortic valve disease. In this review, we will present the current available literature regarding the appropriate management of these patients.

Aortic Valve↗
PubMed2003

Distal myocardial protection during percutaneous coronary intervention with an intracoronary beta-blocker.

BACKGROUND: Experimental studies have demonstrated that intravenous beta-blocker administration before coronary artery occlusion significantly reduces myocardial injury. Clinical studies have shown that intracoronary (IC) propranolol administration before percutaneous coronary intervention (PCI) delays myocardial ischemia. The present study tested the hypothesis that IC propranolol treatment protects ischemic myocardium from myocardial damage and reduces the incidence of myocardial infarction (MI) and short-term adverse outcomes after PCI. METHODS AND RESULTS: Patients undergoing PCI (n=150) were randomly assigned in a double-blind fashion to receive IC propranolol (n=75) or placebo (n=75). Study drug was delivered before first balloon inflation via an intracoronary catheter with the tip distal to the coronary lesion. Biochemical markers were evaluated through the first 24 hours and clinical outcomes to 30 days. Evidence of MI with creatine kinase-MB elevation after PCI was seen in 36% of placebo and 17% of propranolol patients (P=0.01). Troponin T elevation was seen in 33% of placebo and 13% of propranolol patients (P=0.005). At 30 days, the composite end point of death, postprocedural MI, non-Q-wave MI after PCI hospitalization, or urgent target-lesion revascularization occurred in 40% of placebo versus 18% of propranolol patients (hazard ratio 2.14, 95% CI 1.24 to 3.71, P=0.004). CONCLUSIONS: IC administration of propranolol protects the myocardium during PCI, significantly reducing the incidence of MI and improving short-term clinical outcomes.

Adrenergic beta-Antagonists↗
PubMed2003

The current status of immune modulating therapy for myocarditis: a case of acute parvovirus myocarditis treated with intravenous immunoglobulin.

We present a case of a patient who presented with a febrile illness without obvious source initially, who developed profound cardiac decompensation and left ventricular dysfunction. Viral titers obtained during the course of illness confirmed parvovirus infection. Intravenous aggressive immunoglobulins and medical therapy for heart failure resulted in stabilization and, ultimately, a complete recovery. Recent data from clinical trials are discussed regarding the utility of immunoglobulins in the treatment of myocarditis and heart failure.

Acute Disease↗
PubMed2002

Late coronary stent thrombosis: early vs. late stent thrombosis in the stent era.

The incidence of coronary stent thrombosis is < 1%-2% in recent studies, with the highest-risk period considered to be the first 30 days following stent implantation. Recently, stent thrombosis after 30 days has been reported in patients undergoing brachytherapy with stenting. We reviewed the incidence of stent thrombosis causing myocardial infarction in nonbrachytherapy patients at our institution between 1 January 1996 and 30 November 1999. A case control methodology was employed with a 1:3 ratio of stent thrombosis to control patients. Of 1,191 patients undergoing coronary stenting, acute (< 24 hr) plus subacute (1-30 days) stent thrombosis occurred in 0.92% (11 of 1,191 patients). A further 0.76% (9 of 1,191 patients) developed late stent thrombosis after 30 days. There were no clinical or angiographic features at the time of the initial procedure that were associated with stent thrombosis as an entire group compared with control group, but early (acute and subacute) stent thrombosis patients had a smaller final stent minimal lumen diameter and longer stent length compared with patients who had late stent thrombosis or controls. Late stent thrombosis occurs in nonbrachytherapy patients and is almost as frequent as early stent thrombosis. Further studies are required to determine whether longer-term poststent pharmacological treatment may decrease or prevent this complication.

Biomarkers↗