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Timothy D Henry

Publications and source records attributed to Timothy D Henry.

At least 19 recordsLinked to original sources
PubMed2006

ST-segment elevation myocardial infarction: recommendations on triage of patients to heart attack centers: is it time for a national policy for the treatment of ST-segment elevation myocardial infarction?

Despite substantial progress in the diagnosis and treatment of acute ST-segment elevation myocardial infarction (STEMI), implementation of this knowledge into routine clinical practice has been variable. It has become increasing clear that primary percutaneous coronary intervention (PCI) is the preferred method of reperfusion if it can be performed in a timely manner. Recent European data suggest that transfer for direct PCI may also be preferable to fibrinolytic therapy. We believe it is time to establish a national policy for treatment of patients with STEMI to develop a coordinated system of care similar to that of the level 1 trauma system.

Electrocardiography↗
PubMed2006

Comparison of safety and efficacy of sirolimus-eluting stents versus bare metal stents in patients with ST-segment elevation myocardial infarction.

Sirolimus-eluting stents (SESs) are superior to bare metal stents (BMSs) for percutaneous coronary intervention, but data regarding SESs in ST-segment elevation myocardial infarction (STEMI) are limited. We investigated the clinical outcomes of patients with STEMI who were treated with SESs. We measured clinical characteristics and acute and long-term outcomes in 306 consecutive patients with STEMI who received a SES (n = 156) or a BMS (n = 150). Patients were followed for death, nonfatal reinfarction, and target vessel revascularization. Patients with SESs had a 0.6% in-hospital mortality rate versus 5.3% in patients with BMSs (p = 0.015). Six-month mortality rates were 1.9% (SES) and 10.1% (BMS, p = 0.003). At 6 months, patients with SESs were less likely to have target vessel revascularization (1.3% vs 8.1%, p = 0.005) and achieve the composite end point (3.2% vs 16.1%, p = 0.0001). No subacute thrombosis or clinical restenosis occurred in the SES group. Patients who received BMSs were older, received more stents, and had more myocardial damage, worse renal function, and lower ejection fractions than did those in the SES group. By multivariate discriminant analysis, stent type (SES vs BMS) was the most significant determinant of the 6-month composite end point (p = 0.01) and the need for target vessel revascularization (p = 0.02). In conclusion, SESs are safe and effective in STEMI at 6 months.

Age Factors↗
PubMed2006

Myocardial injury and long-term mortality following moderate to severe carbon monoxide poisoning.

CONTEXT: Carbon monoxide (CO) poisoning is a common cause of toxicological morbidity and mortality. Myocardial injury is a frequent consequence of moderate to severe CO poisoning. While the in-hospital mortality for these patients is low, the long-term outcome of myocardial injury in this setting is unknown. OBJECTIVE: To determine the association between myocardial injury and long-term mortality in patients following moderate to severe CO poisoning. DESIGN, SETTING, AND PARTICIPANTS: Prospective cohort study of 230 consecutive adult patients treated for moderate to severe CO poisoning with hyperbaric oxygen and admitted to the Hennepin County Medical Center, a regional center for treatment of CO poisoning, between January 1, 1994, and January 1, 2002. Follow-up was through November 11, 2005. MAIN OUTCOME MEASURE: All-cause mortality. RESULTS: Myocardial injury (cardiac troponin I level > or =0.7 ng/mL or creatine kinase-MB level > or =5.0 ng/mL and/or diagnostic electrocardiogram changes) occurred in 85 (37%) of 230 patients. At a median follow-up of 7.6 years (range: in-hospital only to 11.8 years), there were 54 deaths (24%). Twelve of those deaths (5%) occurred in the hospital as a result of a combination of burn injury and anoxic brain injury (n = 8) or cardiac arrest and anoxic brain injury (n = 4). Among the 85 patients who sustained myocardial injury from CO poisoning, 32 (38%) eventually died compared with 22 (15%) of 145 patients who did not sustain myocardial injury (adjusted hazard ratio, 2.1; 95% confidence interval, 1.2-3.7; P = .009). CONCLUSION: Myocardial injury occurs frequently in patients hospitalized for moderate to severe CO poisoning and is a significant predictor of mortality.

Adult↗
PubMed2006

Acute coronary syndromes in patients with renal disease: what are the issues?

Patients with chronic kidney disease and acute coronary syndromes are at high risk for both bleeding and ischemic events. This risk increases with the severity of renal insufficiency. Management for acute coronary syndromes in the setting of kidney disease is a paradox; as the benefit of current treatment is high, so is the risk for complications. Patients with chronic renal disease are frequently excluded from randomized clinical trials, and therefore, the optimal treatment strategies are often speculative in this high-risk patient population. Additional research is needed to further refine the optimal management of patients with chronic kidney disease in the setting of acute coronary syndromes.

Acute Disease↗
PubMed2006

Rationale for establishing regional ST-elevation myocardial infarction receiving center (SRC) networks.

Recent developments have provided a unique opportunity for the organization of regional ST-elevation myocardial infarction (STEMI) receiving center (SRC) networks. Because cumulative evidence has demonstrated that rapid primary percutaneous coronary intervention (PCI) is the most effective reperfusion strategy for acute STEMI, the development of integrated SRC networks could extend the benefits of primary PCI to a much larger segment of the US population. Factors that favor the development of regional SRC networks include results from recently published clinical trials, insight into contemporary STEMI treatment patterns from observational registries, experience with the nation's current trauma system, and technological advances. In addition, the 2004 American College of Cardiology/American Heart Association STEMI guidelines have specified that optimal "first medical contact-to-balloon" times should be <90 minutes, so a clear benchmark for timely reperfusion has been established. Achievement of this benchmark will require improvements in the current process of care as well as increased multidisciplinary cooperation between emergency medical services, emergency medicine physicians, and cardiologists. Two types of regional SRC networks have already begun to evolve in role-model cities, including prehospital cardiac triage and interhospital transfer. Regional coordination of SRC networks is needed to ensure quality monitoring and to delineate the ideal reperfusion strategy for a given community based on available resources and expertise.

Angioplasty, Balloon, Coronary↗
PubMed2006

Evaluation and management of the patient who has cocaine-associated chest pain.

Patients who have chest pain following the use of cocaine have become more common in emergency departments throughout the United States,with approximately 6% of these patients sustaining an acute MI. The authors have described the rationale for recommending aspirin, benzodiaze-pines, and nitroglycerin as first-line treatments and calcium-channel blockade or phentolamine as possible second-line therapies and have summarized the controversies surrounding the use of fibrinolytic agents. Admission for observation is one reasonable approach to the management of the low-risk cohort. Evaluation for underlying coronary artery disease is reasonable, particularly in patients who have acute MI. Patients who do not have infarction can undergo evaluation for possible coronary artery disease on an outpatient basis. Routine interventions for secondary prophylaxis as well as cocaine rehabilitation should be used in this patient population, because the long-term prognosis seems somewhat dependent upon the ability of the patient to discontinue cocaine use.

Chest Pain↗
PubMed2006

Primer: practical approach to the selection of patients for and application of EECP.

Over the past decade, the frequency of use of enhanced external counterpulsation (EECP) has increased in patients with angina, irrespective of medical therapy and coronary revascularization status. Many patients referred for EECP have one or more comorbidities that could affect this treatment's efficacy, safety, or both. By use of data from more than 8,000 patients enrolled in the International EECP Patient Registry, we provide practical guidelines for the selection and treatment of patients. We have focused on considerations for patients who have one or more of the following characteristics: age older than 75 years, diabetes, obesity, heart failure, and peripheral vascular disease. We have also reviewed outcomes and treatment recommendations for individuals with poor diastolic augmentation during treatment, for those with atrial fibrillation or pacemakers, and for those receiving anticoagulation therapy. Lastly, we examined relevant data regarding extended courses of EECP, repeat therapy, or both. While clinical studies have demonstrated the usefulness of EECP in selected patients, these guidelines permit recommendations for the extended application of this important treatment to subsets of patients excluded from clinical trials.

Aged↗
PubMed2005

Effectiveness of the concomitant use of bivalirudin and drug-eluting stents (from the prospective, multicenter BivAlirudin and Drug-Eluting STents [ADEST] study).

Sirolimus-eluting stents (SESs) reduce restenosis compared with bare metal stents. Safety issues with drug-eluting stents are particularly important given concerns of possible increased thrombogenicity. Compared with heparin plus glycoprotein IIb/IIIa inhibitors, the direct thrombin inhibitor bivalirudin has been shown to reduce the risk of hemorrhagic complications in patients receiving bare metal stents, with similar efficacy in preventing ischemic complications. The safety and efficacy of percutaneous coronary intervention (PCI) with SESs and bivalirudin anticoagulation have not been prospectively studied. This prospective study performed at 9 United States hospitals evaluated 1,182 patients referred for PCI with SESs in whom the procedural anticoagulant was bivalirudin. Clopidogrel was administered before PCI in 79% of patients, and only 5.3% received procedural glycoprotein IIb/IIIa inhibitors. At 30 days, major adverse cardiac events occurred in 7.1% of patients, including 0.3% mortality, 4.4% myocardial infarction (defined as creatine kinase-MB >3x normal), 1.7% target vessel revascularization, and 0.6% stent thrombosis. Major bleeding occurred in only 0.8% of patients. Thus, use of bivalirudin as the procedural anticoagulant to support SES implantation in a "real world" population of patients undergoing PCI results in low rates of major adverse cardiac events, stent thrombosis, and major bleeding.

Angioplasty, Balloon, Coronary↗
PubMed2005

Increased prevalence of coronary artery aneurysms among cocaine users.

BACKGROUND: Cocaine abuse has been implicated in multiple cardiovascular complications. Coronary artery aneurysms (CAAs) and ectasia occur in 0.2% to 5.3% of patients referred for angiography and are associated with atherosclerosis, Kawasaki's disease, and several rare disorders. After observing CAAs in multiple young cocaine users, we investigated the prevalence of CAAs among cocaine users undergoing coronary angiography. METHODS AND RESULTS: Clinical and angiographic characteristics of 112 consecutive patients with a history of cocaine use and coronary angiography were compared with a control group of similar age and risk factors from an existing angiographic database over the same time period. Coronary angiograms were independently read by 3 reviewers blinded to cocaine use. Cocaine users were young (mean age, 44 years), predominantly male (80%), and cigarette smokers (95%). Control patients had higher rates of diabetes (33%) and more severe coronary artery disease (P=0.01). Previous myocardial infarction was common in both groups (45% of cocaine users, 38% of control patients). Despite the frequent history of myocardial infarction among cocaine users, 48% had nonobstructive coronary artery disease. Among cocaine users, 34 of 112 (30.4%) had CAAs compared with 6 of 79 (7.6%) in the control group (P<0.001). Cocaine use was a strong predictor of CAA by univariate and multivariate analyses. CONCLUSIONS: This is the first description of an association between cocaine use and CAA. The prevalence of CAA among cocaine users was higher than expected (30.4%), given such a young cohort. Cocaine use may predispose to the formation of CAA, which may in turn be a contributing factor to myocardial infarction.

Adult↗
PubMed2005

Cardiovascular manifestations of moderate to severe carbon monoxide poisoning.

OBJECTIVES: We describe the cardiovascular manifestations of carbon monoxide (CO) poisoning. BACKGROUND: Carbon monoxide poisoning is a common cause of toxicologic morbidity and mortality. Although the neurologic sequelae of CO poisoning have been well described, the cardiovascular consequences are limited to isolated case reports. METHODS: We reviewed the cardiovascular manifestations of 230 consecutive patients treated for moderate to severe CO poisoning in the hyperbaric oxygen chamber at Hennepin County Medical Center (HCMC), a regional center for treatment of CO poisoning. RESULTS: The mean age was 47.2 years with 72% men. Ischemic electrocardiogram (ECG) changes were present in 30% of patients, whereas only 16% had a normal ECG. Cardiac biomarkers (creatine kinase-MB fraction or troponin I) were elevated in 35% of patients. In-hospital mortality was 5%. CONCLUSIONS: Cardiovascular sequelae of CO poisoning are frequent, with myocardial injury assessed by biomarkers or ECG in 37% of patients. Patients admitted to the hospital with CO poisoning should have a baseline ECG and serial cardiac biomarkers.

Adult↗
PubMed2005

Extracellular proteases in atherosclerosis and restenosis.

Extracellular proteolysis plays a key role in many pathophysiologic processes including cancer, inflammatory diseases, and cardiovascular conditions such as atherosclerosis and restenosis. Whereas matrix metalloproteinases are their best known member, many others are becoming better known. The extracellular proteases are a complex and heterogeneous superfamily of enzymes. They include metalloproteinases (matrix metalloproteinases, adamalysins, or pappalysins), serine proteases (elastase, coagulation factors, plasmin, tissue plasminogen activator, urokinase plasminogen activator), and the cysteine proteases (such cathepsins). In addition to their matrix degradation capabilities, they have other less well known biologic functions that include angiogenesis, growth factor bioavailability, cytokine modulation, receptor shedding, enhancing cell migration, proliferation, invasion, and apoptosis. This review discusses extracellular proteases relevant to the vasculature, their classification and function, and how protease disorders contribute to arterial plaque growth, including chronic atherosclerosis, acute coronary syndromes, restenosis, and vascular remodeling. These broad extracellular protease functions make them potentially interesting therapeutic targets.

Animals↗
PubMed2005

Design of a standardized system for transfer of patients with ST-elevation myocardial infarction for percutaneous coronary intervention.

BACKGROUND: Direct percutaneous coronary intervention (PCI) is the preferred method of reperfusion for ST-elevation myocardial infarction (STEMI). Transfer from community hospitals to PCI centers increases availability for direct PCI, which improves outcomes compared to fibrinolysis in Europe. It has been difficult to achieve similar door-to-balloon times for transfer patients in the United States. METHODS: We designed a standardized protocol and integrated system of transfer for patients with STEMI. We report the door-to-balloon times for the pre- and postpilot patients in the index hospital and describe the details of the current Level 1 MI Program. RESULTS: In the 15 months before the pilot project, the door-to-balloon time for patients receiving ad hoc transfer for direct PCI was 192 minutes, similar to the national average. The door-to-balloon time for the patients receiving rescue PCI after failed thrombolysis was 221 minutes. The standardized protocol decreased door-to-balloon time to 98 minutes in the pilot trial (P < .01) and has now been applied successfully in 29 community hospitals. CONCLUSIONS: Rapid transfer of patients with STEMI is feasible in the United States using a standardized protocol and integrated transfer system. This requires a team approach with cooperation between cardiologists, emergency physicians, nurses, and the emergency medical system as well as various health care organizations.

Angioplasty, Balloon, Coronary↗
PubMed2005

Implementation of acute myocardial infarction guidelines in community hospitals.

OBJECTIVES: To obtain information regarding the current use of guidelines and protocols and quality assessment practices for the management of ST-segment elevation myocardial infarction in Minnesota hospitals without cardiac catheterization laboratories. METHODS: Structured surveys were mailed in 2003 to emergency department medical directors or nurse managers in 111 hospitals in Minnesota that did not have cardiac catheterization laboratories. Of the 111 hospitals surveyed, 104 (94%) responded. RESULTS: Sixty-three percent of responding hospitals have guidelines or protocols; 57% use standing orders for ST-segment elevation myocardial infarction. Thirty-three percent have neither. Of those with guidelines, protocols, or standing orders, 8% address triage and transfer criteria, 86% thrombolytics, 91% aspirin, and 71% beta-blockers. Fifty percent have quality assessment processes in place for ST-segment elevation myocardial infarction. CONCLUSIONS: Recommendations from the National Heart Attack Alert Program issued more than ten years ago and, more recently, the updated American College of Cardiology/American Heart Association Guidelines for the Management of Patients With ST-Elevation Myocardial Infarction suggest development of emergency department and hospital-specific guidelines and protocols for ST-segment elevation myocardial infarction. Currently, only two thirds of community hospitals in Minnesota have these in place; when present, these guidelines are often incomplete and rarely address transfer criteria to hospitals with percutaneous coronary intervention capability. Quality assessment occurred in 50% of hospitals surveyed. Programs to help community hospitals develop and implement guidelines and quality improvement should be encouraged and supported.

Cardiac Catheterization↗
PubMed2004

Plasma cathepsin D isoforms and their active metabolites increase after myocardial infarction and contribute to plasma renin activity.

Plasma renin activity (PRA) is often found to increase after myocardial infarction (MI). Elevated PRA may contribute to increased myocardial angiotensin II that is responsible for maladaptive remodeling of the myocardium after MI. We hypothesized that MI would also result in cardiac release of cathepsin D, a ubiquitous lysosomal enzyme with high renin sequence homology. Cathepsin D release from damaged myocardial tissue could contribute to angiotensin formation by acting as an enzymatic alternate to renin. We assessed circulating renin and cathepsin D from both control and MI patient plasma (7-20 hours after MI) using shallow gradient focusing that allowed for independent measurement of both enzymes. Cathepsin D was increased significantly in the plasma after MI (P < 0.001). Furthermore, circulating active cathepsin D metabolites were also significantly elevated after MI (P < 0.04), and contained the majority of cathepsin D activity in plasma. Spiking control plasma with cathepsin D resulted in a variable but significant (P = 0.005) increase in PRA using a clinical assay. We conclude that 7-20 hours after MI, plasma cathepsin D is significantly elevated and most of the active enzymatic activity is circulating as plasma metabolites. Circulating cathepsin D can falsely increase clinical PRA determinations, and may also provide an alternative angiotensin formation pathway after MI.

Angiotensins↗
PubMed2003

Bivalirudin provides increasing benefit with decreasing renal function: a meta-analysis of randomized trials.

Chronic kidney disease is associated with an increased risk of ischemic and bleeding events after percutaneous coronary intervention (PCI). The direct thrombin inhibitor bivalirudin reduces these combined events. We sought to assess whether this benefit was influenced by renal function. A meta-analysis of 3 randomized trials (n = 5,035) comparing bivalirudin with heparin during PCI, stratified by estimated creatinine clearance using the Cockcroft-Gault equation (>90 [n = 1,578], 90 to 60 [n = 2,163], 59 to 30 [n = 1,255], and <30 ml/min [n = 39]), was conducted. The composite end points of death, myocardial infarction or revascularization, hemorrhage, and combined ischemic or bleeding events were assessed. A common odds ratio for each creatinine clearance strata was estimated with a random-effects model. The interaction between renal impairment and benefit from bivalirudin was assessed. Adverse ischemic and bleeding events increased with decreasing renal function. The relative benefit of bivalirudin with respect to ischemic and bleeding events was maintained within each stratum. The absolute benefit in terms of ischemic and bleeding complications increased with decreasing creatinine clearance (normal 2.2%, mild 5.8%, moderate 7.7%, severe 14.4%; p trend <0.001, interaction p = 0.044). Renal dysfunction remains a prevalent risk factor for ischemic and bleeding events in patients who undergo PCI. Bivalirudin provides greater absolute benefit in patients with impaired renal function.

Adult↗