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David R Holmes

Publications and source records attributed to David R Holmes.

At least 73 records · Page 4Linked to original sources
PubMed2005

Alcohol septal ablation for hypertrophic cardiomyopathy: indications and technique.

Alcohol septal ablation for the treatment of hypertrophic cardiomyopathy has been the subject of great interest, and the number of procedures performed is increasing despite an absence of randomized trial data. Although straightforward in concept, alcohol septal ablation may be considerably more difficult in actual practice. To optimize the results and prevent complications, the anatomy of the septal arcade architecture must be understood and the anatomic relationship between the septal artery and the specific portion of the septum to be ablated must be carefully delineated. For the latter, during the procedure, an echocardiographic contrast medium injection into the septal artery of interest is essential. Selection of the volume and amount of alcohol to be injected varies depending on the size and distribution of the septal artery. Specific complications such as conduction defects, hemodynamic compromise, ventricular arrhythmias, and inadequate gradient reduction can be minimized by specific technical approaches. After ablation, protocols are needed for periprocedural guidelines because some complications may occur late during the next several days. For optimal results, patients need to be selected after catheter assessment and combined echocardiography and angiography, and ablation techniques need to be scientific and rigorous.

Cardiomyopathy, Hypertrophic↗
PubMed2005

Renal and iliac artery stenting by interventional cardiologists and vascular surgeons: the Foundation to Advance Medical Education (FAME) initiative.

The American College of Cardiology, in concert with the Society for Coronary Angiography and Interventions and the Society for Vascular Surgery, planned and implemented an initiative to teach stenting of renal and iliac arteries to their peers in practice. Supported by the Foundation to advance medical Education (FAME), the initiative involved 25 preceptees and 6 preceptors and included a didactic portion (a remote learning exercise), an animal practicum, a procedural simulation, and a preceptor/preceptee training segment, all of which was followed by evaluations by the participants. Assessments of the success of the initiative differed between preceptees, who were positive about the experience, and preceptors, who were more critical of the endeavor (with surgeons more critical than cardiologists). Technical problems, such as obtaining temporary licensure to practice medicine in another state, interfered with the hands-on experiences of several preceptees. Programs such as the FAME initiative will grow in importance as new technologies continue to be introduced into medical practice and the need to train physicians in practice in their use expands.

Animals↗
PubMed2005

Effect of lesion length on fractional flow reserve in intermediate coronary lesions.

BACKGROUND: Fractional flow reserve (FFR) has become a gold standard in physiological assessment of coronary artery stenosis. An FFR < 0.75 is considered as a reliable physiological parameter indicating functionally significant lesion. Lesion length (LL) may affect the translesional hemodynamics. However, the effect of LL on FFR has not been adequately assessed. We sought to evaluate the effect of LL on FFR in patients with angiographically intermediate coronary artery disease. METHODS: We performed FFR measurements by pressure guidewire in 63 intermediate-grade lesions (63 patients) by visual assessment. Lesion length and percent diameter stenosis (%DS) at the lesion site were determined by performing off-line quantitative coronary angiography analysis. RESULTS: Overall, there was a moderate inverse correlation between FFR and %DS (r = -0.55, P < .001). In addition, there was a weak inverse correlation between LL and FFR (r = -0.31, P < .001). Using a receiver operating characteristic curve analysis, an LL > or = 10 mm was identified as the best cutoff value for predicting an FFR < 0.75 (sensitivity 95%, specificity 66%, positive predictive power 48%, and negative predictive power 97%). The correlation between FFR and %DS was significantly improved for LL > or = 10 mm, as compared with LL < 10 mm (r = -0.78, P < .001; r = 0.16, P = NS; respectively). Similar improvement with LL was also observed for intermediate lesions by quantitative coronary angiography (%DS 50%-70%; r = 0.19, P = NS for LL < 10 mm; r = -0.74, P < .001 for LL > or = 10 mm). CONCLUSIONS: This study demonstrates that LL differentially affects the correlation between the functional assessment (FFR) and the "anatomic" severity (%DS) of coronary lesions and suggests that LL has a significant impact on the physiological significance of intermediate-grade coronary lesions.

Aged↗
PubMed2005

Temporal variation in inhospital mortality with percutaneous coronary intervention: a report from the National Heart, Lung and Blood Institute Dynamic Registry.

BACKGROUND: Cardiovascular morbidity and mortality display a distinct time dependence also known as circadian variation. Whether such time dependence extends to the risk of procedural-related mortality after percutaneous coronary intervention (PCI) is presently unknown. METHODS: Inhospital mortality was analyzed in 6,347 patients with PCI start times from 8:00 am to 6:59 pm ("usual" workday). The sample was divided into 3 evenly populated groups (morning start 8:00-10:59 AM, midday start 11:00 AM-1:59 PM, afternoon start 2:00-6:59 PM). The association between procedural start time and mortality was assessed using multivariable analysis including a propensity score accounting for factors associated with procedural start time. RESULTS: There was a significant, nonlinear relationship between procedural-related mortality and start time (P = .03). Afternoon start patients were at higher adjusted risk of mortality compared with midday start patients (OR 2.03, 95% CI 1.07-3.83, P = .03 ). Morning start patients were also at higher risk compared with midday start patients although the association was not statistically significant (OR 1.73, 95% CI 0.89-3.39, P = .11). CONCLUSIONS: There is a significant time-dependent variation in the risk of inhospital PCI-related mortality during usual working hours. The highest risk period, taking into account numerous factors that confound this association, is the latter part of the workday. A second period of apparent greater risk occurs during the early part of the workday and is consistent with our present understanding of circadian variation in cardiovascular disease processes.

Aged↗
PubMed2005

Integrated management of patients with diabetes mellitus and ischemic heart disease: PCI, CABG, and medical therapy.

Modern coronary revascularization strategies are based on studies performed in the 1970s and 1980s that compared coronary artery bypass surgery with standard medical therapy available at the time. Studies comparing surgical and percutaneous revascularization followed, demonstrating similar long-term outcome among thousands of randomized patients. The largest of these trials, the Bypass Angioplasty Revascularization Investigation (BARI), cast doubt on the generalizability of these findings to all subgroups, finding that patients with diabetes mellitus and multivessel disease had worse long-term outcome with an initial strategy of percutaneous transluminal coronary angioplasty (PTCA). Indeed, patients with diabetes mellitus are at increased risk for cardiovascular morbidity and mortality, while the benefit of standard therapies in these patients is attenuated by the underlying metabolic abnormalities and significant comorbidities associated with the diabetic state. However, surgical and percutaneous revascularization techniques continue to evolve. Similarly, modern medical therapy is markedly superior to that available during these early studies, with demonstrable benefit in primary and secondary prevention of vascular events in both diabetic and nondiabetic patients. Ongoing trials will define the impact of current treatment modalities in this important and growing population.

Angioplasty, Balloon, Coronary↗
PubMed2005

Infectious complications of percutaneous vascular closure devices.

OBJECTIVE: To describe the infectious complications of percutaneous vascular closure devices (PVCDs) on the basis of our institutional experience with PVCDs and the published medical literature. PATIENTS AND METHODS: We retrospectively reviewed all cases of PVCD-related Infection seen at the Mayo Clinic in Rochester, Minn, between January 1, 2000, and December 31, 2003, and searched the English language medical literature for all previously published reports. RESULTS: We identified 46 cases in the medical literature and 6 cases from our Institutional database. The median age of patients was 63 years (range, 40-79 years). Diabetes mellitus and obesity were the most common comorbidities. The median Incubation period from device Insertion to presentation with access-site infection was 8 days (range, 2-29 days). The most common presenting symptoms were pain, erythema, fever, swelling, and purulent drainage at the access site. Mycotic pseudoaneurysm (22 cases) was the most common complication. Staphylococcus aureus was responsible for most (75%) of the Infections. All patients underwent surgical debridement, and 54% required reconstructive procedures. The median duration of antibiotic treatment was 28 days (range, 7-42 days). The mortality rate was 6% (3 patients). CONCLUSIONS: Infection associated with PVCD placement is uncommon but is an extremely serious complication. Morbidity is high, and aggressive medical and surgical interventions are required to achieve cure.

Adult↗
PubMed2005

The approach to small vessels in the era of drug-eluting stents.

The treatment of small-vessel disease will occupy an increasingly important part of interventional cardiology practice and this raises several issues. The definition of "small vessels" has great implications for device size selection, and knowledge of "normal" small-vessel dimensions is important. Stents have been applied in the setting of smaller-vessel disease and future iterations of small-vessel stents will need to address several design factors. Stent strut thickness might impact on subsequent restenosis as well as late lumen loss. There has been great interest in the use of drug-eluting stents for small vessels. Randomized clinical trials of sirolimus-eluting versus bare metal stents in the treatment of small-vessel disease have shown significant improvements in the rates of target lesion revascularization and restenosis with sirolimus-eluting stents. These improvements in restenosis rates are attributable to the low levels of late loss with the drug-eluting stent.

Blood Vessel Prosthesis Implantation↗
PubMed2004

Alcohol septal ablation versus surgical septal myectomy: comparison of effects on atrioventricular conduction tissue.

OBJECTIVES: This study was designed to evaluate the effect of septal reduction therapies on the conduction system for patients with hypertrophic cardiomyopathy (HCM). BACKGROUND: Heart block is a potential complication of both catheter-based and surgical procedures to relieve left ventricular outflow tract obstruction in HCM, but it is important to understand the different effects of these treatments on the conduction system. METHODS: The electrocardiograms and postoperative course of patients who underwent percutaneous alcohol septal ablation or surgical myectomy at Mayo Clinic between 1999 and 2003 were reviewed. RESULTS: For the 58 patients who underwent alcohol septal ablation, 21 (36%) developed right bundle branch block. Six patients (12%) developed complete heart block requiring permanent pacing, three of whom had left bundle branch block before the procedure. Among the 117 patients who underwent surgical septal myectomy, 47 (40%) developed left bundle branch block. Four patients (3%) developed heart block requiring permanent pacing after the procedure, three of whom had right bundle branch block preoperatively. CONCLUSIONS: Percutaneous septal ablation selectively produces transmural infarction of the basal mid-septum and adjacent right bundle tissue, whereas surgical myectomy affects the endocardial portion of the basal anterior septum and adjacent left bundle tissue. These observations may help identify patients at risk for complete heart block after septal reduction procedures for HCM.

Atrioventricular Node↗
PubMed2004

Quantitative assessment of angiographic restenosis after sirolimus-eluting stent implantation in native coronary arteries.

BACKGROUND: Sirolimus-eluting stents (SESs) reduce angiographic restenosis in patients with focal, native coronary artery stenoses. This study evaluated the usefulness of SESs in complex native-vessel lesions at high risk for restenosis. METHODS AND RESULTS: Angiographic follow-up at 240 days was obtained in 701 patients with long (15- to 25-mm) lesions in small-diameter (2.5- to 3.5-mm) native vessels who were randomly assigned to treatment with SESs or bare-metal stents (BMSs) in the SIRIUS trial. Quantitative angiographic measurements of minimal lumen diameter and percent diameter stenosis were obtained within the treated segment, within the stent, and within its 5-mm proximal and distal edges. Patients treated with SESs had lower rates of binary (>50% diameter stenosis) angiographic restenosis within the segment (8.9% versus 36.3% with the BMS; P<0.001) and within the stent (3.2% versus 35.4% with the BMS; P<0.001). SESs were associated with significantly less late lumen loss within the treated segment, within the stent, and within its 5-mm proximal and distal edges (all P<0.001). The reduction of restenosis with the SES was consistent in patients at risk for restenosis, including those with small vessels, long lesions, and diabetes mellitus. The frequency of late aneurysms was similar in the 2 groups. CONCLUSIONS: Compared with BMSs, SESs reduced angiographic late lumen loss within the stent and its adjacent 5-mm margins in patients with complex native-vessel lesions.

Aged↗
PubMed2004

Noninvasive identification of patients with early coronary atherosclerosis by assessment of digital reactive hyperemia.

OBJECTIVES: We investigated the value of reactive hyperemia peripheral arterial tonometry (RH-PAT) as a noninvasive tool to identify individuals with coronary microvascular endothelial dysfunction. BACKGROUND: Coronary endothelial dysfunction, a systemic disorder, represents an early stage of atherosclerosis; RH-PAT is a technique to assess peripheral microvascular endothelial function. METHODS: Using RH-PAT, digital pulse volume changes during reactive hyperemia were assessed in 94 patients without obstructive coronary artery disease and either normal (n = 39) or abnormal (n = 55) coronary microvascular endothelial function; RH-PAT index, a measure of reactive hyperemia, was calculated as the ratio of the digital pulse volume during reactive hyperemia divided by that at baseline. RESULTS: Average RH-PAT index was lower in patients with coronary endothelial dysfunction compared with those with normal coronary endothelial function (1.27 +/- 0.05 vs. 1.78 +/- 0.08: p < 0.001). An RH-PAT index <1.35 was found to have a sensitivity of 80% and a specificity of 85% to identify patients with coronary endothelial dysfunction. CONCLUSIONS: Digital hyperemic response, as measured by RH-PAT, is attenuated in patients with coronary microvascular endothelial dysfunction, suggesting a role for RH-PAT as a noninvasive test to identify patients with this disorder.

Coronary Artery Disease↗
PubMed2004

Impact of mild or moderate chronic kidney disease on the frequency of restenosis: results from the PRESTO trial.

OBJECTIVES: The goal of this study was to determine if restenosis is increased in mild and moderate chronic kidney disease (CKD) patients after percutaneous coronary intervention (PCI). BACKGROUND: Mortality is increased in CKD after PCI. Restenosis may contribute to increased late mortality. METHODS: We analyzed 11,187 patients with a creatinine <1.8 mg/dl from the Prevention of REStenosis with Tranilast and its Outcomes (PRESTO) trial, grouped by estimated creatinine clearance (CrCl) (<60, 60 to 89, >89 ml/min). The Cox proportional hazards models investigated the association between CrCl group and death, myocardial infarction, and target vessel revascularization (TVR). Generalized estimating equation regression models determined the association between CrCl group and lesion-specific restenosis. RESULTS: At 30 days, there was no difference in myocardial infarction, death, or TVR between the CrCl groups. At nine months, mortality was higher in the lowest CrCl group (2.2%, 1.2%, 0.8%; p < 0.001), which was no longer significant after adjusting for confounding variables. Myocardial infarction and TVR were not different between the groups. In patients undergoing protocol follow-up angiography, restenosis (>/=50%) was not increased with CKD (32%, 32%, 37%; p = 0.02). CONCLUSIONS: Mortality nine months after PCI is mildly increased in mild or moderate CKD patients. However, restenosis is not and does not account for the increased mortality.

Aged↗
PubMed2004

Extracranial thrombotically active carotid plaque as a risk factor for ischemic stroke.

CONTEXT: Recent studies suggest that factors other than the degree of carotid stenosis are involved in ischemic stroke pathogenesis, especially modifications of plaque composition and related complications. OBJECTIVE: To examine the role of carotid plaque rupture and thrombosis in ischemic stroke pathogenesis in patients undergoing carotid endarterectomy, excluding those with possible cardiac embolization or with severe stenosis of the circle of Willis. DESIGN, SETTING, AND PATIENTS: A total of 269 carotid plaques selected from an Interinstitutional Carotid Tissue Bank were studied by histology after surgical endarterectomy between January 1995 and December 2002. A total of 96 plaques were from patients with ipsilateral major stroke, 91 plaques from patients with transient ischemic attack (TIA), and 82 plaques from patients without symptoms. MAIN OUTCOME MEASURES: Differences in the frequency of thrombosis, cap rupture, cap erosion, inflammatory infiltrate, and major cardiovascular risk factors between study groups. RESULTS: A thrombotically active carotid plaque associated with high inflammatory infiltrate was observed in 71 (74.0%) of 96 patients with ipsilateral major stroke (and in all 32 plaques from patients operated within 2 months of symptom onset) compared with 32 (35.2%) of 91 patients with TIA (P < .001) or 12 (14.6%) of 82 patients who were without symptoms (P < .001). In addition, a fresh thrombus was observed in 53.8% of patients with stroke operated 13 to 24 months after the cerebrovascular event. An acute thrombus was associated with cap rupture in 64 (90.1%) of 71 thrombosed plaques from patients with stroke and with cap erosion in the remaining 7 cases (9.9%). Ruptured plaques of patients affected by stroke were characterized by the presence of a more severe inflammatory infiltrate, constituted by monocytes, macrophages, and T lymphocyte cells compared with that observed in the TIA and asymptomatic groups (P = .001). There was no significant difference between groups in major cardiovascular risk factors. CONCLUSION: These results demonstrate a major role of carotid thrombosis and inflammation in ischemic stroke in patients affected by carotid atherosclerotic disease.

Aged↗