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Biomedical subjects

David R Holmes

Publications and source records attributed to David R Holmes.

At least 37 records · Page 2Linked to original sources
PubMed2006

Antiplatelet therapy after percutaneous coronary intervention.

There is intense interest in the relationship between inflammation, thrombosis, platelet aggregation, and hyperlipidemia in patients with coronary artery disease. The specific role of inflammation with its linkage to the coagulation cascade has been well studied. A number of inflammatory markers have been identified which can be used for risk stratification in patients with acute coronary syndromes. Patients with acute coronary syndromes at the time of presentation often have an underlying inflammatory state which needs therapy with antiplatelet regimens including now increasingly frequently clopidogrel in addition to the standard of aspirin. In those patients who are treated medically for their acute coronary syndromes, long-term treatment with dual antiplatelet therapy has been documented to be associated with improved outcome. In patients who undergo an invasive approach with placement of intracoronary stents, the importance of dual antiplatelet therapy is increased. Drug-eluting stents are now used in approximately 90% of all interventional procedures. There is evidence to suggest that while these patients have improved outcome in terms of a decreased need for subsequent procedures to treat restenosis, there is the potential for late subacute stent thrombosis. When late subacute stent thrombosis occurs, it results in mortality or infarction in 40-60% of patients. Dual antiplatelet therapy is therefore recommended for an increasingly longer time in this patient group. At the present time, protocols indicate 3 months for one of the drug-eluting stents and 6 months for the other. However, increasingly longer antiplatelet therapy is being used clinically. Assessment of platelet function during follow-up is as yet early. There are issues about which specific test to use and the definition of platelet hyperreactivity. In the future, more individually targeted therapy may be possible if we can more adequately assess the degree of hyperreactivity and underlying inflammation.

Angioplasty, Balloon, Coronary↗
PubMed2006

A risk score to predict in-hospital mortality for percutaneous coronary interventions.

OBJECTIVES: Our purpose was to develop a risk score to predict in-hospital mortality for percutaneous coronary intervention (PCI) using a statewide population-based PCI registry. BACKGROUND: Risk scores predicting adverse outcomes after PCI have been developed from a single or a small group of hospitals, and their abilities to be generalized to other patient populations might be affected. METHODS: A logistic regression model was developed to predict in-hospital mortality for PCI using data from 46,090 procedures performed in 41 hospitals in the New York State Percutaneous Coronary Intervention Reporting System in 2002. A risk score was derived from this model and was validated using 2003 data from New York. RESULTS: The risk score included nine significant risk factors (age, gender, hemodynamic state, ejection fraction, pre-procedural myocardial infarction, peripheral arterial disease, congestive heart disease, renal failure, and left main disease) that were consistent with other reports. The point values for risk factors range from 1 to 9, and the total risk score ranges from 0 to 40. The observed and recalibrated predicted risks in 2003 were highly correlated for all PCI patients as well as for those in the higher-risk subgroup who suffered myocardial infarctions within 24 h before the procedure. The total risk score for mortality is strongly associated with complication rates and length of stay in the 2003 PCI data. CONCLUSIONS: The risk score accurately predicted in-hospital death for PCI procedures using future New York data. Its performance in other patient populations needs to be further studied.

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PubMed2006

Geographical differences in the rates of angiographic restenosis and ischemia-driven target vessel revascularization after percutaneous coronary interventions: results from the Prevention of Restenosis With Tranilast and its Outcomes (PRESTO) Trial.

UNLABELLED: Many cardiologists consider it reasonable to assume in clinical practice that percutaneous coronary intervention using drug-eluting stents ought to be considered equivalent, if not superior, to bypass surgery. In the absence of a definitive clinical trial to support this view, how should the prudent, cutting-edge cardiologist proceed? OBJECTIVES: This study assessed the geographical differences in target vessel revascularization (TVR) after percutaneous coronary intervention (PCI) in the Prevention of Restenosis With Tranilast and its Outcomes (PRESTO) trial. BACKGROUND: An aggressive approach to PCI is more common in the U.S. than in other countries. The impact of this approach on restenosis outcomes has not been studied. METHODS: Using the PRESTO trial, we compared nine-month ischemic TVR after PCI in U.S.-treated patients (n = 5,026) with rates in other countries (n = 6,458). We defined TVR as repeat intervention for chest pain/positive stress test. Additionally, angiographic restenosis (> or =50% narrowing or > or =50% loss of gain at nine-month follow-up) was compared between U.S. and non-U.S. patients within the prespecified angiographic subset (n = 2,823). Regression models were developed to adjust for clinical and lesion-related characteristics. RESULTS: Higher rates of TVR (18% vs. 11%), and angiographic restenosis (65% vs. 48%) were observed in patients treated in the U.S. as compared with the other patients (p < 0.01 for both comparisons). Patients treated in the U.S. were more likely to be female, diabetic, not currently smoking, to have unstable angina, and to have a prior PCI. In U.S. patients, lesions tended to be longer, but less likely to be American College of Cardiology/American Heart Association class C. After adjusting for clinical and angiographic variables, PCI in the U.S. was still associated with increased angiographic restenosis and ischemic TVR. CONCLUSIONS: Angiographic restenosis and ischemia-driven TVR rates were higher in patients treated in the U.S. The difference could only partially be explained by the higher prevalence of measured adverse clinical and angiographic features.

Angioplasty, Balloon, Coronary↗
PubMed2006

Intravascular ultrasound identification of intraluminal embolic plaque material during carotid angioplasty with stenting.

INTRODUCTION: Carotid angioplasty with stenting (CAS) has evolved as a viable method for treating patients at high risk for carotid endarterectomy. Strokes complicating CAS are most commonly caused by the liberation and distal embolization of embolic material from plaque during the procedure. METHODS: CAS with distal embolic protection (DEP) was performed using the assistance of intravascular ultrasound (IVUS) in a 68-year-old man with asymptomatic carotid artery stenosis. Evaluation of the plaque pretreatment was performed using virtual histology software. IVUS evaluation was also performed after prestent angioplasty, stenting, and poststent angioplasty. RESULTS: Initial degree of angiographic stenosis was 78.9%. Final degree of stenosis was 15.7%. By IVUS, stenosis by minimum lumen diameter and minimum lumen area were 75.6% and 93.4% pretreatment, respectively, and 42.2% and 47.1% posttreatment, respectively. An intraluminal lesion was noted in the distal aspect of the stent after poststent angioplasty but before DEP device removal. Ultrasonographic characteristics of the intraluminal defect were consistent with ruptured plaque material. Angiographic runs failed to demonstrate the lesion. A repeat IVUS run performed approximately 10 min later failed to depict the lesion, suggesting that distal embolization had occurred. Embolic material was noticed in the DEP device after removal. The patient did not experience any ischemic neurological symptoms. CONCLUSIONS: IVUS can identify intraluminal plaque material, which may be a precursor for embolism and delayed ischemic events after CAS. IVUS may allow for treatment before distal embolization of plaque material. Virtual histology IVUS software may help to identify carotid lesions at higher risk for significant embolization during CAS.

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PubMed2006

The SYNergy between percutaneous coronary intervention with TAXus and cardiac surgery (SYNTAX) study: design, rationale, and run-in phase.

BACKGROUND: Changes in the treatment of coronary artery disease both surgically and percutaneously have rendered the major randomized trials historical. Furthermore, the restrictive criteria of previous trials excluded most patients treated in daily practice. Although coronary surgery is still considered the current, evidence-based, gold-standard treatment of left main (LM) and 3-vessel coronary disease, the added benefit of drug-eluting stents has further expanded the use of percutaneous coronary intervention (PCI) beyond less complex populations in daily practice. STUDY DESIGN: The 1500-patient, prospective, multicenter, multinational (European and North American), randomized SYNTAX study with nested registries will enroll "all-comers." Consecutive patients with de novo 3-vessel disease (3VD) and/or LM disease will be screened for eligibility by the Heart Team (composed of an interventionalist, a cardiac surgeon, and the study coordinator) at each site and then allocated to either (1) the randomized cohort, if comparable revascularization can be achieved by either PCI or coronary artery bypass surgery (CABG), or (2) to one of the nested registries for CABG-ineligible patients (PCI registry) or for PCI-ineligible patients (CABG registry). Randomized patients will be stratified based on LM disease and diabetes by site. The primary end point for the randomized comparison is noninferiority of major adverse cardiac and cerebral events between the 2 groups at 1 year. To adequately project the expected enrollment rate per site, a run-in phase was mandated for each site interested in participating in the trial. Both cardiothoracic and interventional cardiology departments within the same institution were asked to complete a questionnaire regarding their frequency of treatment of LM and 3VD over a retrospective 3-month period. IMPLICATIONS: By replacing most traditional inclusion and exclusion criteria with the real-world decision between the cardiothoracic surgeon and the interventionalist, this study will define the roles of CABG and PCI using drug-eluting stents in the contemporary management of LM and 3VD. Results of the run-in phase were used by the steering committee to determine eligibility and to project enrollment for each site.

Angioplasty, Balloon, Coronary↗
PubMed2006

Rescue percutaneous coronary intervention after failed fibrinolytic therapy: have expectations been met?

BACKGROUND: Reperfusion therapy for acute myocardial infarction has revolutionized modern cardiovascular care. METHODS AND RESULTS: Two strategies have been tested widely: fibrinolytic therapy and percutaneous coronary intervention (PCI). Fibrinolytic therapy has the advantage that it can be given in many medical care institutions that do not have immediate access to catheterization laboratories. Unfortunately, in a substantial number of patients, fibrinolytic therapy may not achieve optimal results, and a strategy of rescue or salvage PCI may be undertaken. There is a relative paucity of evidence-based outcomes on which to judge the merits of rescue PCI, although the volume is increasing. CONCLUSIONS: At present, several recommendations can be offered: (1) implementation of a policy of rescue PCI requires clear guidelines of patient selection, training of personnel, logistics of patient movement, and outcomes assessment; and (2) there needs to be heightened awareness with a high index of suspicion about the potential failure of fibrinolytic therapy.

Angioplasty, Balloon, Coronary↗
PubMed2006

Potential applicability and utilization of left atrial appendage occlusion devices in patients with atrial fibrillation.

BACKGROUND: The WATCHMAN left atrial appendage occluder device (Atritech, Inc, Minneapolis, MN) is currently being tested in a Food and Drug Administration-approved clinical trial, the PROTECT AF trial, for patients who are diagnosed with paroxysmal, persistent, or permanent nonvalvular atrial fibrillation. However, rigorous screening and the study design have resulted in the exclusion of a large number of patients. Hence, the purpose of this study was to assess the potential utility of this device among those who were eligible but excluded for trial criteria and the reasons for exclusion. METHODS: Screening logs from the respective sites participating in the PROTECT AF trial were collected and analyzed for potential utilization outside of a research trial. Only 31 patients were enrolled into the research trail from the screening of 1798 total patients. RESULTS: Information from the excluded patients was examined and it was determined that 79% of these patients would be eligible for the device outside the research trial. Twenty-one percent of patients were not able to receive the device because of long-term warfarin need, contraindications to warfarin, unsuitable anatomy as determined by echocardiography, or the inability to take short-term aspirin and clopidogrel for protocol requirements. CONCLUSIONS: Should a device like the WATCHMAN left atrial appendage occluder be approved, approximately 79% of all patients with atrial fibrillation would be eligible for device placement.

Atrial Appendage↗
PubMed2006

Drug-eluting coronary stents.

The introduction and widespread use of coronary stents have been the most important advancement in the percutaneous treatment of coronary artery disease since the introduction of balloon angioplasty. Coronary artery stents reduce the rate of angiographic and clinical restenosis compared to balloon angioplasty. This angiographic restenosis was further reduced with the introduction of drug-eluting stents and hence further reduction in the frequency of major adverse cardiac events. Herein we present a comprehensive and up-to-date review about the use of drug-eluting stents in the treatment of coronary artery disease.

Anti-Inflammatory Agents↗
PubMed2006

Elective percutaneous coronary intervention without on-site cardiac surgery: clinical and economic implications.

BACKGROUND: Low procedural complication rates, barriers to access, and patient preference have encouraged the development of percutaneous coronary intervention (PCI) programs at centers that are often closer to home but without on-site cardiac surgical capability. OBJECTIVES: We compared clinical and economic outcomes associated with performing low-risk elective PCI at a community hospital without on-site cardiac surgery with those obtained at a more remote tertiary care center with on-site cardiac surgery. DESIGN AND MEASURES: We matched 257 patients undergoing low-risk, elective PCI at a community hospital (Immanuel St. Joseph's Hospital [ISJ] between January 27, 2000, and July 31, 2002) to 514 PCI patients treated at a tertiary care hospital (Saint Marys Hospital [SMH] between January 27, 2000, and April 30, 2002) based on clinical and lesion criteria. Clinical outcomes (in-hospital procedural success and target vessel failure during long-term follow up) and economic outcomes (direct medical costs, billed charges, and hospital length of stay [LOS]) were compared between groups. The Mayo Clinic PCI Registry (containing clinical, angiographic, and follow-up data) and administrative data were used in matching and outcomes assessment. RESULTS: Procedural success was achieved more often among ISJ-treated patients (99% vs. 95%; P = 0.02); however, no difference in target vessel failure rates was observed during a median follow-up time of 3.1 years (estimated 1-year event rate: 15.2% vs. 14.8%; P = 0.46). ISJ-treated patients incurred, on average, $3024 more in estimated total costs ($13,771 vs. $10,746; P < 0.001) and $6084 more in billed charges (P < 0.001), but incurred similar LOS post procedure (1.53 days). CONCLUSIONS: Similar clinical outcomes were achieved at a community hospital without on-site cardiac surgery but at significantly increased direct medical cost. Patients, providers, hospitals, payers, and policymakers should consider whether the benefits associated with locally provided specialized cardiovascular services warrant this additional cost.

Cardiac Care Facilities↗
PubMed2006

The 5-year projection on the future of interventional cardiology.

Interventional cardiology has revolutionized modern cardiovascular care not only with the introduction of new approaches to the treatment of coronary artery disease, but also with the development of new invasive approaches to electrophysiologic procedures and the treatment of noncoronary vascular beds. This revolution continues to gather speed. Creative solutions continue to be proposed, evaluated, and then brought to the patient care arena. Issues remain, but these identify opportunities for continuing improvement.

Cardiac Surgical Procedures↗
PubMed2006

Medical devices and pharmaceuticals: differences in public acceptance.

In the past 15 years, rapid technologic advances have introduced medical devices for clinical use that have transformed the care of patients with chronic diseases, especially heart disease. These devices have become truly lifesaving, and their effectiveness has been demonstrated in randomized clinical trials and cost-effectiveness studies. At the same time, a remarkable number of pharmaceutical agents with new actions and capabilities have also been introduced into clinical use. These new compounds have altered the practice of oncology and the care of patients with hematologic malignancies, sometimes with significant improvement in survival. There have been other drugs introduced to manage chronic diseases that alter quality of life but do not usually threaten survival. Recent problems related to the COX-2 anti-inflammatory drugs and ongoing controversies associated with them have raised public awareness; however, there is even more concern about device failures and recalls that have occurred during the same time frame. There is limited information as to why there is such an apparent difference in public opinion toward adverse drug events compared with device problems that lead to advisories or recalls. Among possible reasons are that an implantable device that requires a catheter-based surgical procedure, with its need for hospitalization and detailed explanation about all the potential risks, may be emotionally and intellectually processed differently by a patient/family compared with having a change in prescription from one drug to another.

Cost-Benefit Analysis↗
PubMed2006

Intravascular ultrasound for intracranial angioplasty and stent placement: technical case report.

OBJECTIVE: Intravascular ultrasound (IVUS) imaging has been used extensively in coronary artery interventions and has provided invaluable information for the understanding and treatment of coronary arterial disease. We present here the first description, to our knowledge, of IVUS-guided intracranial arterial interventions in the clinical setting. CLINICAL PRESENTATION: Two patients underwent intracranial angioplasty and stent placement with the assistance of IVUS for the evaluation of their lesions. One patient underwent stenting to treat an occlusive dissection of the left internal carotid artery that occurred during arteriovenous malformation embolization. Another patient underwent angioplasty and stenting for high-grade restenosis of a basilar artery atherosclerotic lesion. RESULTS: Both patients underwent successful revascularization procedures. The patient with the dissection had a small intraventricular and parenchymal hemorrhage documented by computed tomography 4 hours after treatment, but did not develop hydrocephalus or further hemorrhage. Both patients did well clinically and had no permanent neurological deficits. IVUS provided important information in terms of lesion evaluation, stent selection, and stent placement in each case. CONCLUSION: IVUS of the intracranial circulation may assist the performance of intracranial angioplasty and stenting. It provides useful information that can affect clinical decisions. It may prove to be a valuable tool in clinical use and enhance our understanding of vascular disease of the intracranial circulation, as it has in the coronary circulation.

Aged↗
PubMed2006

Lipid-rich plaque masquerading as a coronary thrombus.

A 43-year-old woman presented with exertional chest pressure. Right coronary angiography showed a clear filling defect. Intravascular ultrasound revealed a plaque with 80% stenosis and a large lipid pool. Therefore, a stent was placed, and the patient became angina-free. Lipid-rich plaques are a cause of angiographic filling defects. Intravascular ultrasound is an integral part of coronary artery evaluation.

Adult↗
PubMed2006

Economic and clinical outcomes of a physician-led continuous quality improvement intervention in the delivery of percutaneous coronary intervention.

OBJECTIVE: To compare clinical and economic outcomes associated with percutaneous coronary intervention (PCI) in cohorts before and after continuous quality improvement (CQI) was instituted. STUDY DESIGN: Observational study. METHODS: Clinical, angiographic, procedural, and outcome data on 1441 pre-CQI and 1760 post-CQI PCIs (performed in 1997 and 1998, respectively) were derived from an institutional PCI registry. Administrative data were used to estimate total procedural and postprocedural costs and length of stay (LOS). Logistic and generalized linear modeling was used to adjust in-hospital clinical and economic outcomes, respectively, for differences in patient characteristics. RESULTS: The 2 cohorts were similar in terms of age, sex, and rate of diabetes. Post-CQI patients more often received intracoronary stents, had urgent PCIs, had a history of prior PCI, and received glycoprotein IIb/IIIa inhibitors. Procedural success without in-hospital complications occurred in 90% of both cohorts and did not differ statistically in adjusted analyses. Compared with patients treated pre-CQI, those treated post-CQI had a reduced adjusted odds ratio for in-hospital death or any myocardial infarction (odds ratio = 0.66; 95% confidence interval = 0.46, 0.95). Models predicted a mean postprocedural LOS difference of 0.8 days (2.8 days pre-CQI vs 2.0 days post-CQI; P <.001) and an average post-CQI cost savings of $5430 (P <.001). CONCLUSION: Physician-led, multidisciplinary practice management efforts were successful at significantly reducing PCI-related costs in an era of rapid technological advances while maintaining and perhaps improving quality of care.

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PubMed2005

Emergency coronary artery bypass surgery for percutaneous coronary interventions: changes in the incidence, clinical characteristics, and indications from 1979 to 2003.

OBJECTIVES: The purpose of the current study was to evaluate the changes in incidence, clinical characteristics, and indications for emergency coronary artery bypass grafting (CABG) in patients undergoing percutaneous coronary intervention (PCI) from 1979 to 2003. BACKGROUND: Emergency CABG after PCI is associated with significant morbidity and mortality. METHODS: Data from 23,087 patients who underwent PCI at Mayo Clinic from 1979 to 2003 were analyzed. Patients were divided into three groups: the "pre-stent" era, 1979 to 1994 (n = 8,905); the "initial stent era," 1995 to 1999 (n = 7,605); and the "current stent era," 2000 to 2003 (n = 6,577). RESULTS: Although patients undergoing PCI in the recent time periods had more high-risk features, there was a significant decrease in the incidence of emergency CABG from 2.9% to 0.7% to 0.3% across the groups (p < 0.001). Patients requiring emergency surgery in the recent time periods had a higher prevalence of hypertension, prior revascularization, and left ventricular dysfunction (ejection fraction <40%), as well as more complex coronary lesions. Fewer patients in the current stent era had coronary artery dissections and abrupt vessel closure requiring emergency CABG. The in-hospital mortality rate for emergency CABG patients remains unchanged and ranges from 10% to 14%. CONCLUSIONS: The current study demonstrates that despite the increase in high-risk patients undergoing PCI, there has been a marked decrease in the incidence of patients requiring emergency CABG. However, the in-hospital mortality rate for those requiring emergency CABG remains high and unchanged.

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PubMed2005

Coronary stent restenosis in patients treated with cilostazol.

BACKGROUND: Restenosis after implantation of coronary artery stents remains a significant clinical problem. We undertook a randomized, double-blind, placebo-controlled trial to determine whether cilostazol, a drug that suppresses intimal proliferation, would reduce renarrowing in patients after stent implantation in native coronary arteries. METHODS AND RESULTS: We assigned 705 patients who had successful coronary stent implantation to receive, in addition to aspirin, cilostazol 100 mg BID or placebo for 6 months; clopidogrel 75 mg daily was administered to all patients for 30 days. Restenosis was determined by quantitative coronary angiography at 6 months. The minimal luminal diameter at 6 months for cilostazol-treated patients was 1.77 mm for the analysis segment (stent plus 5-mm borders) compared with 1.62 mm in the placebo group (P=0.01). Restenosis, defined as > or =50% narrowing, occurred in 22.0% of patients in the cilostazol group and in 34.5% of the placebo group (P=0.002), a 36% relative risk reduction. Restenosis was significantly lower in cilostazol-treated diabetics (17.7% versus 37.7%, P=0.01) and in those with small vessels (23.6% versus 35.2%, P=0.02), long lesions (29.9% versus 46.6%, P=0.04), and left anterior descending coronary artery site (19.3% versus 39.8%, P=0.001). There was no difference in bleeding, rehospitalization, target-vessel revascularization, myocardial infarction, or death. CONCLUSIONS: Treatment with the drug cilostazol resulted in a significantly larger minimal luminal diameter and a significantly lower binary restenosis rate compared with placebo-treated patients. These favorable effects were apparent in patients at high risk for restenosis.

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