The natural course of hemodynamically stable pulmonary embolism: Clinical outcome and risk factors in a large prospective cohort study

BACKGROUND: Pulmonary embolism (PE) is a potentially fatal disease with risks of recurrent venous thrombotic events (venous thromboembolism [VTE]) and major bleeding from anticoagulant therapy. Identifying risk factors for recurrent VTE, bleeding, and mortality may guide clinical decision making. OBJECTIVE: To evaluate the incidence of recurrent VTE, hemorrhagic complications, and mortality in patients with PE, and to identify risk factors and the time course of these events. DESIGN: We evaluated consecutive patients with PE derived from a prospective management study, who were followed for 3 months, treated with anticoagulants, and underwent objective diagnostic testing for suspected recurrent VTE or bleeding. RESULTS: Of 673 patients with complete follow-up, 20 patients (3.0%; 95% confidence interval [CI], 1.8 to 4.6%) had recurrent VTE. Eleven of 14 patients with recurrent PE had a fatal PE (79%; 95% CI, 49 to 95%), occurring mostly in the first week after diagnosis of initial PE. In 23 patients (3.4%; 95% CI, 2.2 to 5.1%), a hemorrhagic complication occurred, 10 of which were major bleeds (1.5%; 95% CI, 0.7 to 2.7%), and 2 were fatal (0.3%; 95% CI, 0.04 to 1.1%). During the 3-month follow-up, 55 patients died (8.2%; 95% CI, 6.2 to 10.5%). Risk factors for recurrent VTE were immobilization for > 3 days and being an inpatient; having COPD or malignancies were risk factors for bleeding. Higher age, immobilization, malignancy, and being an inpatient were risk factors for mortality. CONCLUSIONS: Recurrent VTE occurred in a small percentage of patients treated for an acute PE, and the majority of recurrent PEs were fatal. Immobilization, hospitalization, age, COPD, and malignancies were risk factors for recurrent VTE, bleeding, and mortality. Close monitoring may be indicated in these patients, precluding them from out-of-hospital start of treatment.     

Twice vs three times daily heparin dosing for thromboembolism prophylaxis in the general medical population: A metaanalysis

OBJECTIVES: Prophylaxis with unfractionated heparin (UFH) has been proven to reduce rates of venous thromboembolism (VTE) in hospitalized medical patients. While twice-daily (BID) and three-times-daily (TID) dosing regimens have been studied, the two have never been directly compared. We performed a metaanalysis to assess whether TID is superior to BID dosing in the prevention of VTE. METHODS: Medline, EMBASE, and Cochrane Controlled Trials Register from 1966 through December 2004 were searched for randomized trials comparing subcutaneously dosed UHF (either BID or TID) with placebo or control for VTE prophylaxis in medical patient populations. Two reviewers independently rated study quality on the basis of predetermined criteria. Data were extracted on patient age, hospital setting, comorbidities, VTE rates, and bleeding complications. RESULTS: Twelve studies were identified; 7,978 patients (1,664 patients in the TID arm, and 6,314 patients in the BID arm) were included. After adjustment for baseline risk, there was no difference in the overall rate (per 1,000 patient-days) of VTE (BID, 5.4; vs TID, 3.5; p = 0.87). TID heparin showed a trend toward a decrease in pulmonary embolism (PE) [BID, 1.5; vs TID, 0.5; p = 0.09] and in proximal DVT and PE (BID, 2.3; vs TID, 0.9; p = 0.05). The risk for major bleeding was significantly increased with TID heparin (BID, 0.35; vs TID, 0.96; p < 0.001). CONCLUSIONS: BID heparin dosing causes fewer major bleeding episodes, while TID dosing appears to offer somewhat better efficacy in preventing clinically relevant VTE events. Practitioners should use underlying risk for VTE and bleeding to individualize pharmacologic prevention.     

Clinical outcome of patients with upper-extremity deep vein thrombosis: results from the RIETE Registry

BACKGROUND: There is little information on the clinical outcome of patients with upper-extremity deep vein thrombosis (DVT). METHODS: RIETE is an ongoing registry of consecutive patients with objectively confirmed, symptomatic, acute DVT or pulmonary embolism (PE). In this analysis, we analyzed the demographic characteristics, treatment, and 3-month outcome of all patients with DVT in the arm. RESULTS: Of the 11,564 DVT patients enrolled, 512 patients (4.4%) had arm DVT. They presented less often with clinically overt PE (9.0% vs 29%; odds ratio, 0.24; 95% confidence interval [CI], 0.18 to 0.33) than those with lower-limb DVT, but their 3-month outcome was similar. Of the 512 patients with arm DVT, 196 patients (38%) had cancer and 228 patients (45%) had catheter-related DVT. During follow-up, those with cancer DVT had an increased incidence of major bleeding (4.1% vs 0.9%; odds ratio, 4.4; 95% CI, 1.2 to 21), recurrent venous thromboembolism (6.1% vs 2.8%; odds ratio, 2.2; 95% CI, 0.91 to 5.6; p = 0.04), and death (22% vs 3.5%; odds ratio, 7.8; 95% CI, 4.0 to 16). Thirty patients had the composite event of recurrent DVT, symptomatic PE, or major bleeding. They were significantly older, more often had cancer, and presented more frequently with symptomatic PE on hospital admission. On multivariate analysis, only cancer patients with arm DVT had an increased risk for the composite event (odds ratio, 3.0; 95% CI, 1.4 to 6.4). CONCLUSIONS: At presentation, patients with arm DVT have less often clinically overt PE than those with lower-limb DVT, but their 3-month outcome is similar. Among patients with arm DVT, those with cancer have the worse outcome.     

Differences between low-molecular-weight and unfractionated heparin for venous thromboembolism prevention following ischemic stroke: a metaanalysis

BACKGROUND: Venous thromboembolism (VTE) remains a major cause of morbidity following stroke. The optimal form of pharmacologic prophylaxis following stroke is unknown. METHODS: We identified randomized trials comparing unfractionated heparin (UFH) to low-molecular-weight heparin (LMWH) for VTE prevention in ischemic stroke patients. We focused on the risk for VTE, pulmonary embolism (PE), bleeding, and mortality as a function of the type of agent used for prophylaxis. Findings were pooled with a random-effects model. RESULTS: We identified three trials including 2,028 patients. Two of the studies were blinded, two studies relied on enoxaparin, while one study utilized certoparin. In two studies, UFH was administered three times a day, while it was administered twice daily in the remaining study. The use of LMWH was associated with a significant risk reduction for any VTE (odds ratio [OR], 0.54; 95% confidence interval [CI], 0.41 to 0.70; p < 0.001). Limiting the analysis to proximal VTEs also indicated that LMWHs were superior (OR with LMWH vs UFH, 0.53; 95% CI, 0.37 to 0.75; p < 0.001). LMWH use led to fewer PEs as well (OR, 0.26; 95% CI, 0.07 to 0.95; p = 0.042). There were no differences in rates of overall bleeding, intracranial hemorrhage, or mortality based on the type of agent employed. Restricting the analysis to the reports employing enoxaparin did not alter our findings. CONCLUSIONS: The prophylactic use of LMWH compared to UFH following ischemic stroke is associated with a reduction in both VTE and PE. This benefit is not associated with an increased incidence of bleeding. Broader use of LMWH for VTE prevention after ischemic stroke is warranted.     

Copeptin, C-reactive protein, and procalcitonin as prognostic biomarkers in acute exacerbation of COPD

BACKGROUND: A novel approach to estimate the severity of COPD exacerbation and predict its outcome is the use of biomarkers. We assessed circulating levels of copeptin, the precursor of vasopressin, C-reactive protein (CRP), and procalcitonin as potential prognostic parameters for in-hospital and long-term outcomes in patients with acute exacerbation of COPD (AECOPD) requiring hospitalization. METHODS: Data of 167 patients (mean age, 70 years; mean FEV(1), 39.9 +/- 16.9 of predicted [+/- SD]) presenting to the emergency department due to AECOPD were analyzed. Patients were evaluated based on clinical, laboratory, and lung function parameters on hospital admission, at 14 days, and at 6 months. RESULTS: Plasma levels of all three biomarkers were elevated during the acute exacerbation (p < 0.001), but levels at 14 days and 6 months were similar (p = not significant). CRP was significantly higher in patients presenting with Anthonisen type I exacerbation (p = 0.003). In contrast to CRP and procalcitonin, copeptin on hospital admission was associated with a prolonged hospital stay (p = 0.002) and long-term clinical failure (p < 0.0001). Only copeptin was predictive for long-term clinical failure independent of age, comorbidity, hypoxemia, and lung functional impairment in multivariate analysis (p = 0.005). The combination of copeptin and previous hospitalization for COPD increased the risk of poor outcome (p < 0.0001). Long-term clinical failure was observed in 11% of cases with copeptin < 40 pmol/L and no history of hospitalization, as compared to 73% of patients with copeptin >/= 40 pmol/L and a history of hospitalization (p < 0.0001). CONCLUSIONS: We suggest copeptin as a prognostic marker for short-term and long-term prognoses in patients with AECOPD requiring hospitalization.     

Atrial septostomy in treatment of end-stage right heart failure in patients with pulmonary hypertension

BACKGROUND: Right ventricular (RV) failure is the main cause of death in patients with pulmonary hypertension (PH). Balloon atrial septostomy (BAS) is believed to relieve symptoms of PH by increasing systemic flow and reducing RV preload. METHODS: Fourteen BAS procedures were performed in 11 patients (5 men and 6 women; mean [+/- SD] age, 33 +/- 12 years) with RV failure in the course of PH that was refractory to conventional treatment. BAS consisted of a puncture of the interatrial septum and subsequent dilatations with balloons of increasing diameter in a step-by-step manner. RESULTS: After BAS, the mean oxygen saturation of aortic blood decreased (before, 93 +/- 4%; after, 84 +/- 4%; p = 0.001), while mean cardiac index increased (before, 1.54 +/- 0.34 L/min/m(2); after, 1.78 +/- 0.35 L/min/m(2); p = 0.001), resulting in a positive trend for mean systemic oxygen transport (before, 270 +/- 64 mL/min; after, 286 +/- 81 mL/min; p = 0.08). Pulmonary vascular resistance (PVR) slightly increased immediately after the procedure, and this rise inversely correlated with mixed venous blood partial oxygen pressure both before BAS (r = -0.69; p = 0.009) and after BAS (r = -0.64; p = 0.018). Mean functional class improved from 3.2 +/- 0.4 to 2.6 +/- 0.7 (p = 0.03) after 1 month. At follow-up (mean time to follow-up, 8.1 +/- 6.2 months; range, 0.8 to 20.2 months), seven patients died and two underwent lung transplantation. There was no difference in the survival rate compared to that obtained from National Institutes of Health equation. A significant size reduction in the created defect was observed in six patients, requiring repeat BAS procedures in three cases. CONCLUSIONS: The current BAS technique improves cardiac index and functional class without significant periprocedural complications, except for a transient increase in PVR related to acute desaturation of mixed venous blood. At long-term follow-up, a high incidence of spontaneous decrease in orifice size has been observed.     

Prognosis of patients with heart failure and obstructive sleep apnea treated with continuous positive airway pressure

BACKGROUND: Therapy with continuous positive airway pressure (CPAP) provides several benefits for patients with heart failure (HF) complicated by obstructive sleep apnea (OSA). However, the effect on the prognosis of such patients remains unknown. Aims: To determine whether CPAP therapy and compliance affects the prognosis of HF patients with OSA. METHODS: We classified 88 patients with HF and moderate-to-severe OSA into a CPAP-treated group (n = 65) and an untreated group (n = 23), and then those treated with CPAP were further subclassified according to CPAP therapy compliance. The frequency of death and hospitalization was analyzed using multivariate analysis. RESULTS: During a mean (+/- SD) period of 25.3 +/- 15.3 months, 44.3% of the patients died or were hospitalized. Multivariate analysis showed that the risk for death and hospitalization was increased in the untreated group (hazard ratio [HR], 2.03; 95% confidence interval [CI], 1.07 to 3.68; p = 0.030) and in less compliant CPAP-treated patients (HR, 4.02; 95% CI, 1.33 to 12.2; p = 0.014). CONCLUSION: Therapy with CPAP significantly reduced the risk of death and hospitalization among patients with HF and OSA. However, reduced compliance with CPAP therapy was significantly associated with an increased risk of death and hospitalization.     

Leukocytosis in acute pulmonary embolism.

PURPOSE: The purpose of this investigation is to assess the level of leukocytosis in acute pulmonary embolism (PE). BACKGROUND: Limited data exist regarding leukocytosis in acute PE. One reason that the prevalence of leukocytosis in acute PE is unknown, despite an extensive number of investigations of PE, may relate to the fact that acute PE is usually associated with other conditions that themselves may cause leukocytosis. METHODS: Hospital records of 386 patients with a diagnosis of acute PE were reviewed retrospectively. Patients with no other possible or definite cause of leukocytosis were analyzed separately. A diagnosis of PE was made by a high-probability interpretation of the ventilation/perfusion lung scan or pulmonary angiogram. RESULTS: Among patients with PE in whom other possible or defined causes for leukocytosis were eliminated, 52 of 266 (20%) had a WBC count > 10,000/mm3. None had a WBC count that was > or = 20,000/mm3. Patients with the pulmonary hemorrhage/infarction syndrome had an increased WBC count in 32 of 183 (17%) vs 20 of 83 (24%) in patients who did not have pulmonary hemorrhage/infarction syndrome (not significant). CONCLUSION: A modest leukocytosis may accompany (and possibly be caused by) PE. Its presence should not dissuade the clinician from objectively pursuing the diagnosis of PE.     

New definition and natural history of patients with diffuse pulmonary arteriovenous malformations: twenty-seven-year experience

BACKGROUND: Patients with diffuse pulmonary arteriovenous malformations (PAVM), a small but important subset of the PAVM population, have significant morbidity and mortality rates. METHODS: Thirty-six patients (21 female and 15 male) with diffuse PAVM from a cohort of 821 consecutive patients with PAVM were evaluated. Diffuse PAVM were categorized angiographically: involvement of one or more segmental pulmonary arteries in one or both lungs. Hereditary hemorrhagic telangiectasia (HHT) status, gender, presence or absence of large (> or = 3-mm diameter artery) focal PAVM, oxygen saturations, complications including hemoptysis, years of follow-up, and survival were tabulated. RESULTS: HHT was present in 29 of 36 patients (81%), and diffuse PAVM were more commonly bilateral (26 of 36 patients, 72%) than unilateral (10 of 36 patients, 28%) [p = 0.02]. Female gender was associated with bilateral diffuse PAVM (19 of 26 patients, 73%) [p = 0.01]. Focal PAVM were present in both groups but more commonly in patients with bilateral involvement (16 of 26 patients, 62%) [p = 0.02]. Initial oxygen saturations (pulse oximetry, standing) of patients with unilateral and bilateral diffuse PAVM were 87 +/- 7% and 79 +/- 8% (mean +/- SD), respectively (p = 0.02). The last or current values for patients with unilateral and bilateral involvement are 95 +/- 3% and 85 +/- 7%, respectively (p < 0.0001). Nine deaths occurred, and all were in patients with bilateral involvement. Deaths were due to hemoptysis of bronchial artery origin (n = 2), hemorrhage from duodenal ulcer (n = 1), spontaneous liver necrosis (n = 3), brain hemorrhage (n = 1), brain abscess (n = 1), and operative death during attempted lung transplant (n = 1). CONCLUSIONS: Patients with diffuse PAVM are a high-risk group, and yearly follow-up is recommended.     

The effects of 1-year treatment with a herbst mandibular advancement splint on obstructive sleep apnea, oxidative stress, and endothelial function

BACKGROUND: Obstructive sleep apnea (OSA) is associated with endothelial dysfunction. In the current study, we assessed the effect of long-term modified Herbst mandibular advancement splint (MAS) treatment on OSA, oxidative stress markers, and on endothelial function (EF). METHODS: A total of 16 subjects participated (11 men and 5 women; mean [+/- SD] age, 54.0 +/- 8.3 years; mean body mass index, 28.0 +/- 3.1 kg/m(2)), 12 of whom completed the 1-year evaluation. Apnea severity, levels of oxidative stress markers, and EF were assessed after 3 months and 1 year of receiving treatment. For comparison, 6 untreated patients underwent two evaluations 9 months apart, and 10 non-OSA individuals were assessed once as a reference group. The results are presented as the mean +/- SD. RESULTS: The mean apnea-hypopnea index (AHI) decreased significantly from 29.7 +/- 18.5 events/h before treatment to 17.7 +/- 11.1 events/h after 3 months of treatment and 19.6 +/- 11.5 events/h after 1 year of treatment (p < 0.005 for both). The mean Epworth sleepiness scale score decreased significantly from 12.4 +/- 6.0 before treatment to 10.2 +/- 6.6 after 3 months of treatment and 7.8 +/- 3.8 after 1 year of treatment (p < 0.001 for both). The mean EF improved significantly from 1.77 +/- 0.4 before treatment to 2.1 +/- 0.4 after 3 months of treatment (p < 0.05) and 2.0 +/- 0.3 after 1 year of treatment (p = 0.055), which were similar to the values of the reference group. Thiobarbituric acid-reactive substance (TBARS) levels decreased from 18.8 +/- 6.2 nmol malondialdehyde (MDA)/mL before treatment to 15.8 +/- 3.9 MDA/mL after 3 months of treatment (p = 0.09) and 15.5 +/- 3.2 nmol MDA/mL after 1 year of treatment (p < 0.05). There was a correlation between the improvement in AHI and in EF or TBARS levels (r = 0.55; p = 0.05). The untreated control group remained unchanged. CONCLUSIONS: The Herbst MAS may be a moderately effective long-term treatment for patients with OSA. EF improved to levels that were not significantly different than reference levels, even though apneic events were not completely eliminated. We think that these data are encouraging and that they justify the performance of larger randomized controlled studies.     

Clinical characteristics and outcomes of obstetric patients requiring ICU admission

OBJECTIVES: To review a series of critically ill obstetric patients admitted to our ICU to assess the spectrum of disease, required interventions, and fetal/maternal mortality, and to identify conditions associated with maternal death. DESIGN: Retrospective cohort. SETTING: Medical-surgical ICU in a university-affiliated hospital. PATIENTS: Pregnant/postpartum admissions between January 1, 1998, and September 30, 2005. INTERVENTIONS: None. MEASUREMENTS AND RESULTS: We studied 161 patients (age, 28 +/- 9 years; mean gestational age, 29 +/- 9 weeks) [mean +/- SD], constituting 10% of 1,571 hospital admissions. APACHE (acute physiology and chronic health evaluation) II score was 14 +/- 8, with 24% predicted mortality; sequential organ failure assessment score was 5 +/- 3; and therapeutic intervention scoring system at 24 h was 25 +/- 9. Forty-one percent of patients required mechanical ventilation (MV). ARDS, shock, and organ dysfunction were present in 19%, 25%, and 48% of patients, respectively. Most patients (63%) were admitted postpartum, and 74% of admissions were of obstetric cause. Hypertensive disease (40%), major hemorrhage (16%), septic abortion (12%), and nonobstetric sepsis (10%) were the principal diagnoses. Maternal mortality was 11%, with multiple organ dysfunction syndrome (44%) and intracranial hemorrhage (39%) as main causes. There were no differences in death rate in patients admitted for obstetric and nonobstetric causes. Fetal mortality was 32%. Only 30% of patients received antenatal care, which was more frequent in survivors (33% vs 6% nonsurvivors, p = 0.014). CONCLUSIONS: Although ARDS, organ failures, shock, and use of MV were extremely frequent in this population, maternal mortality remains within an acceptable range. APACHE II overpredicted mortality in these patients. Septic abortion is still an important modifiable cause of mortality. Efforts should concentrate in increasing antenatal care, which was clearly underprovided in these patients.     

Diagnostic and prognostic utility of brain natriuretic Peptide in subjects admitted to the ICU with hypoxic respiratory failure due to noncardiogenic and cardiogenic pulmonary edema

BACKGROUND: Brain natriuretic peptide (BNP) is useful in diagnosing congestive heart failure (CHF) in patients presenting in the emergency department with acute dyspnea. We prospectively tested the utility of BNP for discriminating ARDS vs cardiogenic pulmonary edema (CPE). METHODS: We enrolled ICU patients with acute hypoxemic respiratory failure and bilateral pulmonary infiltrates who were undergoing right-heart catheterization (RHC) to aid in diagnosis. Patients with acute coronary syndrome, end-stage renal disease, recent coronary artery bypass graft surgery, or preexisting left ventricular ejection fraction /= 1,200 pg/mL, BNP had a specificity of 92% for CPE. Higher levels of BNP were associated with a decreased odds for ARDS (odds ratio, 0.4 per log increase; p = 0.007) after adjustment for age, history of CHF, and right atrial pressure. BNP was associated with in-hospital mortality (p = 0.03) irrespective of the final diagnosis and independent of APACHE (acute physiology and chronic health evaluation) II score. CONCLUSION: In ICU patients with hypoxemic respiratory failure, BNP appears useful in excluding CPE and identifying patients with a high probability of ARDS, and was associated with mortality in patients with both ARDS and CPE. Larger studies are necessary to validate these findings.     

A comparative study of community-acquired pneumonia patients admitted to the ward and the ICU

BACKGROUND: Limited information is available on the health-care utilization of hospitalized patients with community-acquired pneumonia (CAP) depending on the location of care. Our aim was to compare the clinical characteristics, etiologies, and outcomes of patients with CAP who were admitted to the ICU with those admitted who were to the ward service. METHODS: A retrospective cohort study, at two tertiary teaching hospitals, one of which was a Veterans Affairs hospital, and the other a county hospital. Eligible subjects had been admitted to the hospital with a diagnosis of CAP between January 1, 1999, and December 31, 2001, had a confirmatory chest radiograph, and a hospital discharge International Classification of Diseases, ninth revision, diagnosis of pneumonia. Subjects were excluded from the study if they had designated "comfort measures only" or had been transferred from another acute care hospital or were nursing home patients. Bivariate and multivariable analysis evaluated 30-day and 90-day mortality as the dependent measures. RESULTS: Data were abstracted on 730 patients (ICU, 145 patients; wards, 585 patients). Compared to ward patients, ICU patients were more likely to be male (p = 0.001), and to have congestive heart failure (p = 0.01) and COPD (p = 0.01). ICU patients also had higher mean pneumonia severity index scores (112 [SD, 35] vs 83 [SD, 30], respectively; p = 0.02). Patients admitted to the ICU had a longer mean length of hospital stay (12 days [SD, 10 days] vs 7 days [SD, 17 days], respectively; p = 0.07), and a higher 30-day mortality rate (23% vs 4%, respectively; p < 0.001) and 90-day mortality rate (28% vs 8%, respectively; p < 0.001) compared to ward patients. CONCLUSIONS: ICU patients present with more severe disease and more comorbidities. ICU patients stay longer in the hospital and have a much higher mortality rate when compared to ward patients. Management strategies should be designed to improve clinical outcomes in ICU patients.     

Outcome of patients with small-vessel vasculitis admitted to a medical ICU

PURPOSES: This study aims to describe the clinical course and prognostic factors of patients with small-vessel vasculitis admitted to a medical ICU. METHODS: We reviewed the clinical records of 38 patients with small-vessel vasculitis admitted consecutively to the ICU between January 1997 and May 2004. The APACHE (acute physiology and chronic health evaluation) III prognostic system was used to determine the severity of illness on the first ICU day; the sequential organ failure assessment (SOFA) score was used to measure organ dysfunction, and the Birmingham vasculitis activity score for Wegener granulomatosis (BVAS/WG) was used to assess vasculitis activity. Outcome measures were the 28-day mortality and ICU length of stay. RESULTS: Nineteen patients (50%) had Wegener granulomatosis, 16 patients (42%) had microscopic polyangiitis, 2 patients had CNS vasculitis, and 1 patient had Churg-Strauss syndrome. Reasons for ICU admission included alveolar hemorrhage in 14 patients (37%), sepsis in 5 patients (13%), seizures in 3 patients (8%), and pneumonia in 2 patients (5%). The median ICU length of stay was 4.0 days (interquartile range, 2.0 to 6.0 days). The APACHE III score was lower in survivors than nonsurvivors (p = 0.010). The predicted hospital mortality was 54% for nonsurvivors and 21% for survivors (p = 0.0038). The mean SOFA score was 11.6 (SD, 2.6) in nonsurvivors, compared to 6.9 (SD, 2.4) in survivors (p = 0.0004). Mean BVAS/WG scores were 8.6 (SD, 3.6) in nonsurvivors and 4.7 (SD, 4.6) in survivors (p = 0.0889). Twenty-six percent of the patients received invasive mechanical ventilation, and 33% underwent dialysis. The 28-day and 1-year mortality rates were 11% and 29%, respectively. CONCLUSIONS: The mortality of patients with small-vessel vasculitis admitted to the ICU is lower than predicted, and alveolar hemorrhage is the most common reason for ICU admission.     

Pulse pressure and cardiovascular events in postmenopausal women with coronary heart disease

BACKGROUND: Pulse pressure (PP) has been shown to predict risk for cardiovascular events in men; however, this association has not been well established in women. Hormone replacement therapy may improve arterial compliance, but findings from cross-sectional and prospective studies report inconsistent results. We sought to examine the relationship between PP and risk for cardiovascular events, and to determine the effect of hormone therapy on PP in postmenopausal women with coronary heart disease (CHD). METHODS AND RESULTS: A total of 2,763 postmenopausal women (mean age, 66 +/- 7 years [+/- SD]) with CHD in the Heart and Estrogen/Progestin Replacement Study, a randomized, placebo-controlled, secondary CHD prevention trial of estrogen plus progestin, were followed up on average for 4.1 years. BP was measured at baseline and annually. Mean baseline PP was 62 +/- 16 mm Hg. There were 361 myocardial infarctions (MIs) or CHD deaths, 265 hospitalizations for congestive heart failure (CHF), and 215 strokes or transient ischemic attacks (TIAs). Women in the highest quartile of PP at baseline had a 47% increase in risk for MI or CHD death and more than a twofold increase in risk for stroke and TIA events or hospitalization for CHF (p < 0.01 for each outcome). After adjustment for other cardiovascular risk factors and mean arterial pressure, PP remained significantly associated with incident stroke or TIA events (odds ratio, 1.25; p = 0.02) and hospitalizations for CHF (odds ratio, 1.31; p < 0.01) but not with MI or CHD death. After adjustment for diastolic BP, systolic BP was similarly associated with stroke or TIA (odds ratio, 1.30; p < 0.01) and hospitalized CHF (odds ratio, 1.30; p < 0.01) and was also weakly associated with risk for MI and CHD death (odds ratio, 1.18; p = 0.02). Mean PP was 1- to 2-mm Hg higher in women randomized to hormone replacement therapy vs those receiving placebo (p < 0.01). CONCLUSIONS: PP had predictive value for CHF and stroke or TIA, but not MI or CHD death in this cohort of postmenopausal women with CHD. Use of hormone replacement therapy produced a small, statistically significant increase in PP. Further research is necessary to determine the clinical utility of PP as a potential therapeutic target.     

Prognostic value of circulating levels of endothelin-1 in patients after acute myocardial infarction undergoing primary coronary angioplasty

BACKGROUND: The link between increased circulating level of endothelin (ET)-1 and adverse clinical outcomes after acute myocardial infarction (AMI) has been established. Current studies demonstrate that reperfusion therapy by either thrombolysis or primary percutaneous coronary intervention (PCI) can salvage myocardium, improving survival of AMI patients. However, whether reperfusion therapy by primary PCI can prevent the adverse effect of ET-1 on clinical outcomes in patients after AMI remains unclear. Therefore, this study examined the predictive value of circulating ET-1 levels on 30-day outcomes in ST-segment elevated AMI treated with primary PCI. METHODS AND RESULTS: We conducted a prospective cohort study of 186 consecutive patients with ST-segment elevated AMI of onset < 12 h who underwent primary PCI. Blood samples for plasma concentration of ET-1 were collected in the catheterization laboratory following vascular puncture. Patients were classified into a high group (group 1, ET-1 level >or= 0.632 pg/mL, n = 93) and a low group (group 2, ET-1 level < 0.632 pg/mL, n = 93) according to the median value of ET-1 after AMI. Univariate analysis demonstrated that the 30-day composite major adverse clinical outcomes (MACO) [advanced Killip score >or= 3], severe congestive heart failure (CHF) [New York Heart Association functional class 4], and 30-day mortality were strongly associated with high ET-1 level (>or= 0.632 pg/mL; p < 0.0001), unsuccessful reperfusion (final Thrombolysis in Myocardial Infarction flow 相似文献   

Brain natriuretic peptide in patients with congestive heart failure and central sleep apnea

STUDY OBJECTIVE: To assess the possible relationship between Cheyne-Stokes respiration (CSR) associated with central sleep apnea (CSA) syndrome and brain natriuretic peptide (BNP) in an outpatient population presenting with stable congestive heart failure (CHF). MEASUREMENTS AND RESULTS: Ninety patients with CHF due to systolic dysfunction (left ventricular ejection fraction 相似文献   

Atrial septostomy decreases sympathetic overactivity in pulmonary arterial hypertension

BACKGROUND: We have reported previously that the sympathetic nervous system is activated in patients with pulmonary arterial hypertension (PAH), and that this is only partly explained by a decrease in arterial oxygenation. Possible causes for increased muscle sympathetic nerve activity (MSNA) in patients with PAH include right atrial distension and decreased cardiac output. Both may be improved by atrial septostomy, but this intervention also further decreases arterial oxygenation. In the present study, we wanted to investigate the effect of atrial septostomy on MSNA in patients with PAH. METHODS: We recorded BP, heart rate (HR), arterial O2 saturation (SaO2), and MSNA before and after atrial septostomy in PAH patients (mean [+/- SE] age, 48 +/- 5 years) and in closely matched control subjects. Measurements were also performed after septostomy, while SaO2 was brought to the preprocedure level by supplemental O2 therapy. RESULTS: Compared to the control subjects (n = 10), the PAH patients (n = 11) had a lower mean BP (75 +/- 2 vs 96 +/- 3 mm Hg, respectively; p < 0.001), lower mean SaO2 (92 +/- 1% vs 97 +/- 0%, respectively; p < 0.001), increased mean HR (84 +/- 4 vs 68 +/- 3 beats/min; p < 0.01), and markedly increased mean MSNA (76 +/- 5 vs 29 +/- 2 bursts per minute; p < 0.001). Atrial septostomy decreased mean SaO2 (to 85 +/- 2%; p < 0.001) and mean MSNA (to 69 +/- 4 bursts per minute; p < 0.01), but did not affect HR or BP. Therapy with supplemental O2 did not affect MSNA, BP, or HR. The decrease in MSNA was correlated to the decrease in right atrial pressure (r = 0.62; p < 0.05). CONCLUSIONS: Atrial septostomy in PAH patients decreases sympathetic hyperactivity despite an associated decrease in arterial oxygenation, and this appears to be related to decreased right atrial distension.     

Does Endothelin Play a Role in Chemoreception During Acute Hypoxia in Normal Men?

BACKGROUND: The peripheral chemoreceptors are the dominant reflex mechanism responsible for the rise in ventilation and muscle sympathetic nerve activity (MSNA) in response to hypoxia. Animal studies have suggested that endothelin (ET) plays an important role in chemosensitivity. Moreover, several human clinical conditions in which circulating ET levels are increased are accompanied by enhanced chemoreflex sensitivity. Whether ET plays a role in normal human chemosensitivity is unknown. METHODS: We determined whether bosentan, a nonspecific ET receptor antagonist, would decrease chemoreflex sensitivity in 14 healthy subjects. We assessed the effects of bosentan on the response to isocapnic hypoxia, using a randomized, crossover, double-blinded study design. RESULTS: Bosentan increased mean (+/- SEM) plasma ET levels from 1.97 +/- 0.28 to 2.53 +/- 0.23 pg/mL (p = 0.01). Hypoxia increased mean minute ventilation from 6.7 +/- 0.3 to 8+/0.4 L/min (p < 0.01), mean MSNA from 100 to 111 +/- 5% (p < 0.01), mean heart rate from 67 +/- 3 to 86 +/- 3 beats/min (p < 0.01), and mean systolic BP from 116 +/- 3 to 122 +/- 3 mm Hg (p < 0.01). However, none of these responses differed between therapy with bosentan and therapy with placebo (p = 0.26). Bosentan did not affect the mean MSNA responses to the apneas, during normoxia (change from baseline: placebo, 259 +/- 58%; bosentan, 201 +/- 28%; p = 0.17) or during hypoxia (change from baseline: placebo, 469 +/- 139%; bosentan, 329 +/- 46%; p = 0.24). The durations of the voluntary end-expiratory apneas in normoxia and hypoxia, and the subsequent reductions in oxygen saturation, were also similar with therapy using bosentan and placebo (p = 0.42). CONCLUSION: In healthy men, ET does not play an important role in peripheral chemoreceptor activation by acute hypoxia.