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Jean Boland

Publications and source records attributed to Jean Boland.

8 recordsLinked to original sources
PubMed2005

Clinical performance of a ventricular automatic capture verification algorithm.

BACKGROUND: This study was conducted to evaluate the clinical performance of the ventricular automatic capture feature as implemented in the Insignia I Ultra pacemaker system (Guidant) utilizing a variety of ventricular leads. Currently, the optimal programming of the pacemaker output considers both pacemaker efficiency (prolonging battery longevity) and patient safety (adequate safety margin). The ability of a pacemaker to automatically adjust the ventricular output above the pacing threshold while maintaining the appropriate safety margin has been explored since the early 1970s and is only available today in conjunction with a specific low polarization lead system. METHODS: One hundred and five patients were enrolled from 17 European centers utilizing 31 different types of ventricular leads were followed through their 3-month follow-up visit. There were no restrictions on the type of ventricular leads used. RESULTS: The average mean difference between the commanded autothreshold test (0.652 + 0.335 V) and the manual threshold test (0.651 + 0.335 V) was 0.001 + 0.49 (P < 0.0001). The average mean difference between the ambulatory autothreshold test (0.696 + 0.322 V) and the commanded autothreshold test (0.682 + 0.315 V) was 0.002 + 0.74 (P < 0.0001). Holter recordings confirmed that there were no loss of capture incidences without a backup pulse being delivered. In addition, the mean number of backup pulses delivered in a 24-hour period was less than 0.1% of the total number of paced beats. CONCLUSIONS: This study provided that the automatic capture feature while using a variety of leads accurately determines the ventricular stimulation threshold and safely delivers a backup pulse when required.

Adult↗
PubMed2004

A dose-finding study of fondaparinux in patients with non-ST-segment elevation acute coronary syndromes: the Pentasaccharide in Unstable Angina (PENTUA) Study.

OBJECTIVES: In this dose-finding study, we sought to compare fondaparinux with enoxaparin in patients with acute coronary syndromes (ACS). BACKGROUND: Fondaparinux is a synthetic pentasaccharide that selectively inhibits activated clotting factor X. It has been demonstrated as effective in preventing thromboembolic complications in orthopedic surgery. METHODS: Four doses fondaparinux (2.5, 4, 8, or 12 mg once daily) and enoxaparin (1 mg/kg twice daily) were compared, both given for three to seven days, in patients with ACS without persistent ST-segment elevation. RESULTS: The rates of the combined primary end point of death, myocardial infarction, or recurrent ischemia after nine days were 27.9%, 35.9%, 34.7%, 30.3%, and 35.7% in patients allocated to fondaparinux doses of 2.5, 4, 8, and 12 mg and enoxaparin, respectively (p = NS). In the per-protocol analysis (929 patients who received adequate study drug and had adequate ST-segment monitoring), these figures were 30.0%, 43.5%, 41.0%, 34.8%, and 40.2%. Again, no dose response was observed. The lowest event rates were observed in the 2.5-mg fondaparinux group, which had significantly lower rates than the enoxaparin group as well as for 4 and 8 mg fondaparinux in the per-protocol analysis (p < 0.05). Bleeding rates were low and not different among the patient groups. No differences were observed in fondaparinux concentrations in patients with or without death, myocardial infarction, recurrent ischemia, or bleeding events. CONCLUSIONS: This dose-finding study revealed no dose response for different fondaparinux doses ranging from 2.5 to 12 mg subcutaneously and suggests that the efficacy and safety of fondaparinux may be similar to that of enoxaparin. Further studies with fondaparinux in ACS might include the lowest dose (2.5 mg) investigated in this study.

Acute Disease↗
PubMed2004

Benefits of direct angioplasty for women and men with acute myocardial infarction: results of the Global Use of Strategies to Open Occluded Arteries in Acute Coronary Syndromes Angioplasty (GUSTO II-B) Angioplasty Substudy.

BACKGROUND: Direct angioplasty (PTCA) and thrombolytic therapy are the chief therapies for treating an ST-segment elevation myocardial infarction (MI). OBJECTIVE: This study was designed to evaluate sex differences in the relative benefit of direct PTCA versus thrombolytic therapy among patients enrolled in the Global Use of Strategies to Open Occluded Arteries in Acute Coronary Syndromes Angioplasty (GUSTO II-B PTCA) Substudy. METHODS: Women and men presenting with an acute ST-segment elevation MI were randomized to receive either direct PTCA or accelerated tissue plasminogen activator (t-PA). Patients were then randomized to treatment with either heparin or bivalirudin. A gender analysis of outcome was performed. RESULTS: Women were older than men (68.6 +/- 11.5 vs 59.5 +/- 12.0 years, P <.001) and were more likely to have diabetes (22.5% vs 13.5%, P <.0001) and hypertension (53.3% vs 34.8%, P =.001). After adjusting for differences in baseline variables, the odds ratio (OR) for reaching a 30-day clinical end point (death, nonfatal infarction, or nonfatal disabling stroke) was similar for women and men (1.35, 95% CI 0.88-2.08). The OR for reaching a clinical end point at 30 days for the PTCA-treated women compared with the t-PA-treated women was 0.685 (95% CI 0.36-1.32) and similar to the OR in men, 0.565 (95% CI 0.35-0.91), P for interaction =.535. Because women had a higher event rate than men, the absolute number of major events prevented when treating women with direct PTCA was higher than men (56 events/1000 women treated with PTCA vs 42 events per 1000 men treated with PTCA). CONCLUSIONS: Although the relative benefit of direct PTCA to t-PA for the treatment of an acute MI appears to be similar in women and men, women may derive a larger absolute benefit from direct PTCA.

Aged↗
PubMed2003

Percutaneous coronary intervention for cardiogenic shock in the SHOCK trial.

OBJECTIVES: We examined the clinical, angiographic, and procedural characteristics determining survival after percutaneous coronary intervention (PCI) for cardiogenic shock. BACKGROUND: The SHOCK (SHould we emergently revascularize Occluded coronaries for Cardiogenic shocK?) trial prospectively enrolled patients with shock complicating acute myocardial infarction (MI). Patients were randomized to a strategy of early revascularization or initial medical stabilization. METHODS: Patients randomized to early revascularization underwent PCI or bypass surgery on the basis of predefined clinical criteria. Patients randomized to early revascularization who underwent PCI and had angiographic films available for analysis are the subject of this report (n = 82). RESULTS: The median time from MI to PCI was 11 h. The majority of patients had occluded culprit arteries (Thrombolysis In Myocardial Infarction [TIMI] grade 0 or 1 flow in 62%) and multivessel disease (81%). One-year mortality in PCI patients was 50%. Mortality was 39% if PCI was successful but 85% if unsuccessful (p < 0.001). Mortality was 38% if TIMI flow grade 3 was achieved, 55% with TIMI grade 2 flow, and 100% with TIMI grade 0 or 1 flow (p < 0.001). Mortality was 67% if severe mitral regurgitation was documented. Independent correlates of mortality were as follows: increasing age (p < 0.001), lower systolic blood pressure (p = 0.009), increasing time from randomization to PCI (p = 0.019), lower post-PCI TIMI flow (0/1 vs. 2/3) (p < 0.001), and multivessel PCI (p = 0.040). CONCLUSIONS: Restoration of coronary blood flow is a major predictor of survival in cardiogenic shock. Benefit appears to extend beyond the generally accepted 12-h post-infarction window. Surgery should be considered in shock patients with severe mitral insufficiency or multivessel disease not amenable to relatively complete percutaneous revascularization.

Aged↗
PubMed2003

Correlates of one-year survival inpatients with cardiogenic shock complicating acute myocardial infarction: angiographic findings from the SHOCK trial.

OBJECTIVES: The goal of this study was to describe the core laboratory angiographic findings of "SHould we emergently revascularize Occluded Coronaries for cardiogenic shocK" (SHOCK) trial participants and to determine the relationship of angiographic parameters to one-year survival. BACKGROUND: In the SHOCK trial, emergency revascularization improved one-year survival of patients with cardiogenic shock compared with initial medical stabilization including thrombolysis and intraaortic balloon counterpulsation. METHODS: Coronary angiography was performed by protocol in 147 of 152 (97%) patients in the emergency revascularization (ERV) group and by clinical selection in 100 of 150 (67%) patients in the initial medical stabilization (IMS) group. Of the other 50 IMS patients, 45 of 50 (90%) died rapidly and did not undergo angiography. RESULTS: Left ventricular ejection fraction was correlated with one-year survival in both treatment groups (p < 0.001). In the IMS group, the hazard ratio for death was 2.59 (95% confidence interval 1.47 to 4.58, p = 0.001) per diseased vessel (0/1 vs. 2 vs. 3). In the ERV group, the hazard ratio for death per diseased vessel was 1.11 (95% confidence interval 0.79 to 1.56, p = 0.559). Multivariate analysis of the angiography cohort (without regard for left ventriculogram measurements) identified initial Thrombolysis in Myocardial Infarction flow grade (p = 0.032), number of diseased vessels (for IMS patients only, p = 0.024), and culprit vessel (p = 0.004) as independent correlates of one-year survival, even after adjustment for key clinical factors. In the smaller cohort with left ventricular ejection fraction measured (n = 97), ejection fraction and culprit vessel remained independently correlated with survival. CONCLUSIONS: For patients in cardiogenic shock, left ventricular function and culprit vessel were independent correlates of one-year survival.

Aged↗
PubMed2003

Cardiogenic shock caused by right ventricular infarction: a report from the SHOCK registry.

OBJECTIVES: The purpose of this study was to determine the characteristics and outcomes of patients with acute myocardial infarction (MI) complicated by cardiogenic shock due to predominant right ventricular (RV) infarction. BACKGROUND: Although RV infarction has been shown to have favorable long-term outcomes, the influence of RV infarction on mortality in cardiogenic shock is unknown. METHODS: We evaluated 933 patients in cardiogenic shock due to predominant RV (n = 49) or left ventricular (LV) failure (n = 884) in the SHould we emergently revascularize Occluded coronaries for Cardiogenic shocK? (SHOCK) trial registry. RESULTS: Patients with predominant RV shock were younger, with a lower prevalence of previous MI (25.5 vs. 40.1%, p = 0.047), anterior MI, and multivessel disease (34.8 vs. 77.8%, p < 0.001) and a shorter median time between the index MI and the diagnosis of shock (2.9 vs. 6.2 h, p = 0.003) in comparison to patients with LV shock. In-hospital mortality was 53.1% versus 60.8% (p = 0.296) for patients with predominant RV and LV shock, respectively, and the influence of revascularization on mortality was not different between groups. Multivariate analysis revealed that RV shock was not an independent predictor of lower in-hospital mortality (odds ratio 1.07, 95% confidence interval 0.54 to 2.13). CONCLUSIONS: Despite the younger age, lower rate of anterior MI, and higher prevalence of single-vessel coronary disease of RV compared with LV shock patients, and their similar benefit from revascularization, mortality is unexpectedly high in patients with predominant RV shock and similar to patients with LV shock.

Aged↗
PubMed2003

Influence of thrombolytic therapy, with or without intra-aortic balloon counterpulsation, on 12-month survival in the SHOCK trial.

BACKGROUND: The enhancement of diastolic coronary blood flow by the combination of thrombolytic therapy (TT) and intra-aortic balloon counterpulsation (IABP) in experimental studies provides a rationale for their combined use in acute myocardial infarction (MI) complicated by cardiogenic shock. We examined the relation between TT (with and without IABP) and 12-month survival in the SHould We Emergently Revascularize Occluded Coronaries for Cardiogenic ShocK (SHOCK) Trial. METHODS AND RESULTS: Among 302 patients with myocardial infarction and cardiogenic shock who were randomized in the SHOCK Trial, 16 had absolute contraindications to TT. Among 150 patients randomly assigned to initial medical stabilization (IMS), 63% received TT, as recommended per protocol, compared with 49% of 152 patients randomly assigned to emergency revascularization, in whom TT was not recommended if immediate angiography was available. IABP deployment, which was protocol-recommended, was used in 86% of patients. The rate of severe bleeding was similar in patients receiving TT and in those not receiving TT (31% vs 26%, P =.37). Among patients randomly assigned to IMS, TT was associated with improved 12-month survival (unadjusted mortality hazard ratio, 0.59; P =.01; mortality hazard ratio adjusted for age and prior MI, 0.62; P =.02). TT was not associated with improved 12-month survival among patients randomly assigned to emergency revascularization (unadjusted mortality hazard ratio, 0.93; P =.76; mortality hazard ratio adjusted for age and prior MI, 1.06, P =.81). The test for interaction of TT and randomization group P value was.16, and there was insufficient statistical power to demonstrate a differential effect of TT on 12-month survival by treatment group assignment. CONCLUSIONS: Among patients randomly assigned to IMS in the SHOCK Trial, TT was associated with improved 12-month survival and did not significantly increase the risk of severe bleeding.

Aged↗