Utah Valley Regional Medical Center
Hospital / health systemProvo, Utah, United States
Research output, citation impact, and the most-cited recent papers from Utah Valley Regional Medical Center (United States). Aggregated across the NobleBlocks index of 300M+ scholarly works.
Top-cited papers from Utah Valley Regional Medical Center
Abstract Results with the "sulfo-phospho-vanillin" reaction, much used for determining total serum lipids, have been favorably compared with those for the gravimetric method. We investigated the basic chemistry of the reaction and determined the reactivity of this single reagent with various lipids. Our results suggest that: (a) The reaction requires a carbon-carbon double bond. (b) Concentrated sulfuric acid reacts with unsaturated lipids in the initial step to form a carbonium ion. (c) Phosphoric acid reacts with vanillin to produce a phosphate ester, with a resulting increase in the reactivity of the carbonyl group. (d) The carbonium ion reacts with the carbonyl group of phosphovanillin to form a colored compound, which is stabilized by resonance. (e) Unsaturated compounds with more than one double bond react, but reaction may vary with steric hindrance. (f) The method is reasonably precise, but its accuracy depends primarily on the reference standard used.
BACKGROUND: Nearly half of patients hospitalized with unstable angina eventually receive a non-cardiac-related diagnosis, yet 5 percent of patients with myocardial infarction are inappropriately discharged from the emergency department. We evaluated the safety, efficacy, and cost of admission to a chest-pain observation unit (CPU) located in the emergency department for such patients. METHODS: We performed a community-based, prospective, randomized trial of the safety, efficacy, and cost of admission to a CPU as compared with those of regular hospital admission for patients with unstable angina who were considered to be at intermediate risk for cardiovascular events in the short term. A total of 424 eligible patients were randomly assigned to routine hospital admission (a monitored bed under the care of the cardiology service) or admission to the CPU (where patients were cared for according to a strict protocol including aspirin, heparin, continuous ST-segment monitoring, determination of creatine kinase isoenzyme levels, six hours of observation, and a study of cardiac function). The CPU was managed by the emergency department staff. Patients whose test results were negative were discharged, and the others were hospitalized. Primary outcomes (nonfatal myocardial infarction, death, acute congestive heart failure, stroke, or out-of-hospital cardiac arrest) and use of resources were compared between the two groups. RESULTS: The 212 patients in the hospital-admission group had 15 primary events (13 myocardial infarctions and 2 cases of congestive heart failure), and the 212 patients in the CPU group had 7 events (5 myocardial infarctions, 1 death from cardiovascular causes, and 1 case of congestive heart failure). There was no significant difference in the rate of cardiac events between the two groups (odds ratio for the CPU group as compared with the hospital-admission group, 0.50; 95 percent confidence interval, 0.20 to 1.24). No primary events occurred among the 97 patients who were assigned to the CPU and discharged. Resource use during the first six months was greater among patients assigned to hospital admission than among those assigned to the CPU (P<0.01 by the rank-sum test). CONCLUSIONS: A CPU located in the emergency department can be a safe, effective, and cost-saving means of ensuring that patients with unstable angina who are considered to be at intermediate risk of cardiovascular events receive appropriate care.
OBJECTIVE: To compare the hospital course and clinical outcome of preterm infants with respiratory distress syndrome treated with surfactant and managed with high-frequency oscillatory ventilation (HFOV) or conventional mechanical ventilation (CV) as their primary mode of ventilator support. DESIGN: A prospective randomized clinical trial. SETTING: Three community-based level III neonatal intensive care units. SUBJECTS: A total of 125 neonates who were 35 weeks or less estimated gestation requiring intubation and assisted ventilation for respiratory distress syndrome with arterial to alveolar oxygen ratio less than .50. INTERVENTIONS: Patients were randomized to continue CV (61 patients) or be changed to HFOV (64 patients) after exogenous surfactant administration (100 mg/kg). HFOV was used in a strategy to promote lung recruitment and maintain lung volume. Protocol respiratory care guidelines were followed; otherwise routine care was provided by each neonatal intensive care unit. MEASUREMENTS AND MAIN RESULTS: No differences were noted in demographic features between the two study groups. The study population birth weight was 1.51 +/- .47 kg (mean +/- SD), gestational age was 30.9 +/- 2.5 weeks, and study entry age was 2 to 3 hours. Patients randomized to HFOV demonstrated the following significant findings compared with CV-treated patients: vasopressor support was less intensive; surfactant redosing was not as frequent; oxygenation improved more rapidly and remained higher during the first 7 days; fewer infants required prolonged supplemental oxygen or ventilator support; treatment failure was reduced; more patients survived without chronic lung disease at 30 days; need for continuous supplemental oxygen at discharge was less; frequency of necrotizing enterocolitis illness was lower; there were fewer abnormal hearing tests; and hospital costs were decreased. No differences were seen between the two study groups in the frequency or severity of patent ductus arteriosus, air leak, retinopathy of prematurity, or intraventricular hemorrhage. Length of hospital stay and survival to discharge were similar for HFOV- and CV-treated infants. CONCLUSIONS: When used early with a lung recruitment strategy, HFOV after surfactant replacement resulted in clinical outcomes consistent with a reduction in both acute and chronic lung injury. Benefit was evident for preterm infants both less than or equal to 1 kg and more than 1 kg. In addition, early HFOV treatment may have had a more global effect on patient health throughout the hospitalization, resulting in reduced morbidity and decreased health care cost.
BACKGROUND: Whether or not the muscle bundle within the ligament of Marshall (LOM) can serve as the origin of focal atrial fibrillation (AF) is unknown. METHODS AND RESULTS: A total of 28 consecutive patients with paroxysmal AF underwent balloon-occlusion coronary sinus angiograms to identify the vein of Marshall (VOM). Attempts were then made to advance a 1.5-French electrophysiological catheter into the VOM via the coronary sinus orifice. In 17 of the 28 patients (10 of 17 were men aged 38+/-15 years), cannulation was successful. Double potentials were registered in 8 of these 17 patients. The first potential corresponded with local left atrial activation. The second potential was shorter and narrower than the first. The sequence of activation in the second potential in the VOM was proximal to distal. In 6 patients with direct VOM recordings, we documented that the origin of AF was in the muscle bundle within the LOM. Radiofrequency catheter ablation aimed at the insertion site of the VOM successfully terminated AF in 4 of these 6 patients. CONCLUSIONS: (1) It is possible to cannulate and to record electrical potentials from the VOM. (2) The characteristics of the double potentials within the VOM suggest that the second potential is from the muscle bundle (Marshall bundle) within the LOM. (3) The Marshall bundle may be the origin of focal AF in some patients.
BACKGROUND: The safety and efficacy of early, low-dose, prolonged therapy with inhaled nitric oxide in premature newborns with respiratory failure are uncertain. METHODS: We performed a multicenter, randomized trial involving 793 newborns who were 34 weeks of gestational age or less and had respiratory failure requiring mechanical ventilation. Newborns were randomly assigned to receive either inhaled nitric oxide (5 ppm) or placebo gas for 21 days or until extubation, with stratification according to birth weight (500 to 749 g, 750 to 999 g, or 1000 to 1250 g). The primary efficacy outcome was a composite of death or bronchopulmonary dysplasia at 36 weeks of postmenstrual age. Secondary safety outcomes included severe intracranial hemorrhage, periventricular leukomalacia, and ventriculomegaly. RESULTS: Overall, there was no significant difference in the incidence of death or bronchopulmonary dysplasia between patients receiving inhaled nitric oxide and those receiving placebo (71.6 percent vs. 75.3 percent, P=0.24). However, for infants with a birth weight between 1000 and 1250 g, as compared with placebo, inhaled nitric oxide therapy reduced the incidence of bronchopulmonary dysplasia (29.8 percent vs. 59.6 percent); for the cohort overall, such treatment reduced the combined end point of intracranial hemorrhage, periventricular leukomalacia, or ventriculomegaly (17.5 percent vs. 23.9 percent, P=0.03) and of periventricular leukomalacia alone (5.2 percent vs. 9.0 percent, P=0.048). Inhaled nitric oxide therapy did not increase the incidence of pulmonary hemorrhage or other adverse events. CONCLUSIONS: Among premature newborns with respiratory failure, low-dose inhaled nitric oxide did not reduce the overall incidence of bronchopulmonary dysplasia, except among infants with a birth weight of at least 1000 g, but it did reduce the overall risk of brain injury. (ClinicalTrials.gov number, NCT00006401 [ClinicalTrials.gov].).
Abstract The 22 women interviewed in this study were in a high-risk group for low self-esteem, depression, shame, and other long-term interpersonal difficulties due to their survival of childhood sexual abuse. Unlike many of their contemporaries, they have been able to have relationships, stable careers, and healthy personalities. This paper explores the variables and patterns gathered from their interviews. The resiliency themes extracted included: the ability to find emotional support outside the family; self-regard or the ability to think well of oneself; spirituality; external attribution of blame and cognitive style; and inner-directed locus of control.
OBJECTIVE: Magnesium sulfate may prevent eclampsia by reducing cerebral vasoconstriction and ischemia. Nimodipine is a calcium-channel blocker with specific cerebral vasodilator activity. Our objective was to determine whether nimodipine is more effective than magnesium sulfate for seizure prophylaxis in women with severe preeclampsia. METHODS: We conducted an unblinded, multicenter trial in which 1650 women with severe preeclampsia were randomly assigned to receive either nimodipine (60 mg orally every 4 hours) or intravenous magnesium sulfate (given according to the institutional protocol) from enrollment until 24 hours post partum. High blood pressure was controlled with intravenous hydralazine as needed. The primary outcome measure was the development of eclampsia, as defined by a witnessed tonic-clonic seizure. RESULTS: Demographic and clinical characteristics were similar in the two groups. The women who received nimodipine were more likely to have a seizure than those who received magnesium sulfate (21 of 819 [2.6 percent] vs. 7 of 831 [0.8 percent], P=0.01). The adjusted risk ratio for eclampsia associated with nimodipine, as compared with magnesium sulfate, was 3.2 (95 percent confidence interval, 1.1 to 9.1). The antepartum seizure rates did not differ significantly between groups, but the nimodipine group had a higher rate of postpartum seizures (9 of 819 [1.1 percent] vs. 0 of 831, P=0.01). There were no significant differences in neonatal outcome between the two groups. More women in the magnesium sulfate group than in the nimodipine group needed hydralazine to control blood pressure (54.3 percent vs. 45.7 percent, P<0.001). CONCLUSIONS: Magnesium sulfate is more effective than nimodipine for prophylaxis against seizures in women with severe preeclampsia.
BACKGROUND AND OBJECTIVE: Heated, humidified high-flow nasal cannula (HHHFNC) is commonly used as a noninvasive mode of respiratory support in the NICU. The safety and efficacy of HHHFNC have not been compared with other modes of noninvasive support in large randomized trials. The objective was to assess the efficacy and safety of HHHFNC compared with nasal continuous positive airway pressure (nCPAP) for noninvasive respiratory support in the NICU. METHODS: Randomized, controlled, unblinded noncrossover trial in 432 infants ranging from 28 to 42 weeks' gestational age with planned nCPAP support, as either primary therapy or postextubation. The primary outcome was defined as a need for intubation within 72 hours of applied noninvasive therapy. RESULTS: There was no difference in early failure for HHHFNC (23/212 [10.8%]) versus nCPAP (18/220 [8.2%]; P = .344), subsequent need for any intubation (32/212 [15.1%] vs 25/220 [11.4%]; P = .252), or in any of several adverse outcomes analyzed, including air leak. HHHFNC infants remained on the study mode significantly longer than nCPAP infants (median: 4 vs 2 days, respectively; P < .01), but there were no differences between study groups for days on supplemental oxygen (median: 10 vs 8 days), bronchopulmonary dysplasia (20% vs 16%), or discharge from the hospital on oxygen (19% vs 18%). CONCLUSIONS: Among infants ≥28 weeks' gestational age, HHHFNC appears to have similar efficacy and safety to nCPAP when applied immediately postextubation or early as initial noninvasive support for respiratory dysfunction.
BACKGROUND: : Candidal fungal infection rates in neonates are increasing and are a significant cause of mortality, especially in low birth weight infants. Micafungin is an echinocandin that works by inhibiting 1,3-beta-D-glucan synthase, an enzyme responsible for fungal cell wall synthesis. The objective of this study was to determine the safety and pharmacokinetics of micafungin in premature infants. METHODS: : This was a phase I, single-dose, multicenter, open-label, sequential-dose trial of intravenous micafungin investigating 3 doses (0.75 mg/kg, 1.5 mg/kg and 3.0 mg/kg) in 18 premature infants weighing >1000 g (n = 6 in each dosage group). A further 5 infants (500-1000 g) were enrolled in the 0.75 mg/kg dosage group only. RESULTS: : The mean +/- standard deviation gestational age in the >1000 g dosage group was 26.4 +/- 2.4 weeks and, on entry, patients had one or more of a variety of underlying conditions, including sepsis, pneumonia and other infections caused by Candida or other species. Micafungin pharmacokinetics in preterm infants appears linear. However, premature infants >1000 g on average displayed a shorter half-life (8 hours) and a more rapid rate of clearance (approximately 39 mL/h per kg) compared with published data in older children and adults. All doses of micafungin were well tolerated and no serious drug-related adverse events were observed. CONCLUSIONS: : Single doses of micafungin, ranging up to 3.0 mg/kg, appear well tolerated in premature infants weighing >1000 g. The drug's elimination half-life and total plasma clearance in preterm infants appear dissimilar to published values for these parameters in older children and adults. The reason(s) for this apparent difference remain to be investigated.
We compared the onset of clinical response and safety of two surfactants, poractant alfa (Curosurf, Chiesi Pharmaceuticals, Parma, Italy) and beractant (Survanta, Ross Laboratories, Columbus, OH), for treatment of respiratory distress syndrome (RDS) in preterm infants weighing 750 to 1750 g at birth and <35 weeks gestation. The study was performed as a 20-center prospective, randomized, masked comparison trial. Preterm infants (n = 293) with RDS were randomized to receive an initial dose of either 100 (n = 96) or 200 (n = 99) mg/kg of poractant alfa or 100 ( n = 98) mg/kg of beractant. All repeat dosing was given at 100 mg/kg. The onset of clinical response after the first dose was studied by comparing changes in the fraction of inspired oxygen (F IO(2)) between 0 and 6 hours measured using the area under the curve (F IO(2) AUC (0-6)); other outcomes were assessed for the entire cohort at 28 days and for infants born at < or = 32 weeks gestation at 36 weeks postconceptional age. We found that the mean F IO(2) AUC (0-6) values for the 100 and 200 mg/kg poractant alfa groups were both significantly lower than the mean F IO(2) AUC (0-6) values for the beractant group ( p < 0.005) but were not different from each other. Other outcomes were not different among the three groups for the entire cohort, but in infants born at < or = 32 weeks gestation, mortality up to 36 weeks postconceptional age was significantly less in the 200 mg/kg poractant alfa group than in either the beractant group (3% versus 11%; p = 0.034) or in the 100 mg/kg poractant alfa group (3% versus 11%; p = 0.046). Need for more than one dose of surfactant was significantly lower in infants treated with an initial dose of 200 mg/kg poractant alfa in comparison to the beractant-treated group ( p < 0.002). Treatment with poractant alfa (200 mg/kg initial dose) resulted in rapid reduction in supplemental oxygen with fewer additional doses of surfactant versus treatment with beractant in infants <35 weeks gestation with RDS, and significantly reduced mortality ( p <0.05) than either beractant or poractant alfa (100 mg/kg dosing) in infants < or =32 weeks gestation with RDS.
BACKGROUND: Necrotizing enterocolitis (NEC) sometimes occurs after a transfusion, but it is unclear whether this is a chance association or cause and effect. STUDY DESIGN AND METHODS: We compared features of neonates that developed surgical NEC within 48 hours after transfusion with others that developed NEC not preceded by transfusion. We assessed the blood used for transfusion and feeding practices among NEC cases and controls. RESULTS: Forty neonates developed surgical NEC after a transfusion and 72 developed NEC unrelated to a transfusion. Those with NEC after transfusion were born at earlier gestation (mean 27 weeks, 90% confidence interval [CI] 26-28 years vs. mean 30, 90% CI 29-31; p < 0.001) and were of lower birth weight (mean 981 g, 90% CI 835-1128 g vs. mean 1371 g, 90% CI 1245-1496; p < 0.001) and developed NEC later during their neonatal intensive care unit course (day of life: mean 23, 90% CI 20-27 vs. mean 16, 90% CI 13-19; p < 0.001). Transfusions were more prevalent among those that developed NEC (p < 0.001). The blood transfused to those that developed NEC was not older, but those who developed NEC had been fed larger volumes of milk in the 24 hours before and during transfusion (p = 0.04) and were more likely to have been fed a bovine product during that period (p = 0.004). CONCLUSION: Approximately one-third of surgical NEC cases in our system occurred after a transfusion. We speculate that a target area for reducing the prevalence of posttransfusion NEC involves feeding practices immediately before and during RBC transfusion.
BACKGROUND AND PURPOSE: Several trials have compared vertebral augmentation with nonsurgical treatment for vertebral compression fractures. This trial compares the efficacy and safety of balloon kyphoplasty and vertebroplasty. MATERIALS AND METHODS: Patients with osteoporosis with 1-3 acute fractures (T5-L5) were randomized and treated with kyphoplasty (n = 191) or vertebroplasty (n = 190) and were not blinded to the treatment assignment. Twelve- and 24-month subsequent radiographic fracture incidence was the primary end point. Due to low enrollment and early withdrawals, the study was terminated with 404/1234 (32.7%) patients enrolled. RESULTS: The average age of patients was 75.6 years (77.4% female). Mean procedure duration was longer for kyphoplasty (40.0 versus 31.8 minutes, P < .001). At 12 months, 7.8% fewer patients with kyphoplasty (50/140 versus 57/131) had subsequent radiographic fracture, and there were 8.6% fewer at 24 months (54/110 versus 64/111). The results were not statistically significant (P > .21). When we used time to event for new clinical fractures, kyphoplasty approached statistical significance in longer fracture-free survival (Wilcoxon, P = .0596). Similar pain and function improvements were observed. CT demonstrated lower cement extravasation for kyphoplasty (157/214 versus 164/201 levels treated, P = .047). For kyphoplasty versus vertebroplasty, common adverse events within 30 postoperative days were procedural pain (12/191, 9/190), back pain (14/191, 28/190), and new vertebral fractures (9/191, 17/190); similar 2-year occurrence of device-related cement embolism (1/191, 1/190), procedural pain (3/191, 3/190), back pain (2/191, 3/190), and new vertebral fracture (2/191, 2/190) was observed. CONCLUSIONS: Kyphoplasty and vertebroplasty had similar long-term improvement in pain and disability with similar safety profiles and few device-related complications. Procedure duration was shorter with vertebroplasty. Kyphoplasty had fewer cement leakages and a trend toward longer fracture-free survival.
BACKGROUND: The mechanism of the adrenergic atrial tachyarrhythmia is unclear. We hypothesize that the ligament of Marshall (LOM) is sensitive to adrenergic stimulation and may serve as a source of the adrenergic atrial tachyarrhythmia. METHODS AND RESULTS: We performed computerized mapping studies in isolated-perfused canine left atrial tissues from normal dogs (n=9) and from dogs with chronic atrial fibrillation (AF) induced by 10 to 41 weeks of rapid pacing (n=3). Before isoproterenol, spontaneous activity occurred in only one normal tissue (cycle length, CL >1300 ms). During isoproterenol infusion, automatic rhythm was induced in both normal tissues (CL=578+/-172 ms) and AF tissues (CL=255+/-29 ms, P<0.05). The origin of spontaneous activity was mapped to the LOM. In the AF tissues, but not the normal tissues, we observed the transition from rapid automatic activity to multiple wavelet AF. Ablation of the LOM terminated the spontaneous activity and prevented AF. Immunocytochemical studies of the LOM revealed muscle tracts surrounded by tyrosine hydroxylase-positive (sympathetic) nerves. CONCLUSIONS: We conclude that the LOM is richly innervated by sympathetic nerves and serves as a source of isoproterenol-sensitive focal automatic activity in normal canine atrium. The sensitivity to isoproterenol is upregulated after long-term rapid pacing and may contribute to the development of AF in this model.
Question Is broad-spectrum antibiotic use associated with poor outcomes in community-onset pneumonia after adjusting for confounders? Methods We performed a retrospective, observational cohort study of 1995 adults with pneumonia admitted from four US hospital emergency departments. We used multivariable regressions to investigate the effect of broad-spectrum antibiotics on 30-day mortality, length of stay, cost and Clostridioides difficile infection (CDI). To address indication bias, we developed a propensity score using multilevel (individual provider) generalised linear mixed models to perform inverse-probability of treatment weighting (IPTW) to estimate the average treatment effect in the treated. We also manually reviewed a sample of mortality cases for antibiotic-associated adverse events. Results 39.7% of patients received broad-spectrum antibiotics, but drug-resistant pathogens were recovered in only 3%. Broad-spectrum antibiotics were associated with increased mortality in both the unweighted multivariable model (OR 3.8, 95% CI 2.5–5.9; p<0.001) and IPTW analysis (OR 4.6, 95% CI 2.9–7.5; p<0.001). Broad-spectrum antibiotic use by either analysis was also associated with longer hospital stay, greater cost and increased CDI. Healthcare-associated pneumonia was not associated with mortality independent of broad-spectrum antibiotic use. In manual review we identified antibiotic-associated events in 17.5% of mortality cases. Conclusion Broad-spectrum antibiotics appear to be associated with increased mortality and other poor outcomes in community-onset pneumonia.
Family physicians frequently treat bacterial skin infections in the office and in the hospital. Common skin infections include cellulitis, erysipelas, impetigo, folliculitis, and furuncles and carbuncles. Cellulitis is an infection of the dermis and subcutaneous tissue that has poorly demarcated borders and is usually caused by Streptococcus or Staphylococcus species. Erysipelas is a superficial form of cellulitis with sharply demarcated borders and is caused almost exclusively by Streptococcus. Impetigo is also caused by Streptococcus or Staphylococcus and can lead to lifting of the stratum corneum resulting in the commonly seen bullous effect. Folliculitis is an inflammation of the hair follicles. When the infection is bacterial rather than mechanical in nature, it is most commonly caused by Staphylococcus. If the infection of the follicle is deeper and involves more follicles, it moves into the furuncle and carbuncle stages and usually requires incision and drainage. All of these infections are typically diagnosed by clinical presentation and treated empirically. If antibiotics are required, one that is active against gram-positive organisms such as penicillinase-resistant penicillins, cephalosporins, macrolides, or fluoroquinolones should be chosen. Children, patients who have diabetes, or patients who have immunodeficiencies are more susceptible to gram-negative infections and may require treatment with a second- or third-generation cephalosporin.
One of the more challenging cases facing a pediatric anesthesiologist is the management of patients presenting with an anterior mediastinal mass (AMM). Patients with an AMM may have severe cardiopulmonary compromise that can be exacerbated when undergoing general anesthesia. Several case reports have documented cardiopulmonary collapse during induction or maintenance of general anesthesia and even for procedures done without anesthesia. Despite increased understanding and management of these patients, perioperative complications, defined as anything from transient decreases in blood pressure correcting with fluids or mild airway obstruction requiring no intervention, to complete cardiopulmonary collapse, are still estimated to occur during 9% to 20% of anesthetic procedures. The purpose of this review article is to provide foundational knowledge of the anatomy and physiology of a patient with an AMM, with particular emphasis on the pediatric patient. It will assist in recognizing presenting signs and symptoms and discuss the appropriate preoperative testing, which together can help assess perioperative risk and determine the appropriate anesthetic management plan for the patient's safety and comfort.
INTRODUCTION: The origin of double potentials inside the left superior pulmonary vein and their relation to the mechanisms of idiopathic paroxysmal focal atrial fibrillation (AF) are unclear. METHODS AND RESULTS: A total of 40 patients were studied. Group I included 15 patients who underwent radiofrequency catheter ablation of accessory pathway. Double potentials were found inside the left superior pulmonary vein during sinus rhythm in 10 patients and during premature atrial contractions in the remaining five patients. Group II included 25 patients with idiopathic paroxysmal AF. Double potentials were also identified in the left superior pulmonary vein. In 15 patients (Group IIA), the earliest automatic discharge during premature atrial contractions and at the onset of AF was within the left superior pulmonary vein. AF was ablated by radiofrequency energy application at the site registering double potentials. Radiofrequency ablation in the remaining 10 patients failed to terminate AF (Group IIB). The patients in Group IIA had significantly more male patients and more frequent premature atrial contractions and atrial tachycardia on 24-hour Holter recordings prior to the procedure than patients in Group IIB. CONCLUSIONS: Double potentials are present at the left superior pulmonary veins in patients with and without a history of AF. The first potential is due to the activation of atrial myocardium and the second is due to the activation of a different muscular structure. Rapid discharge of this structure triggers episodes of paroxysmal AF. Patients with focal AF originating from the left superior pulmonary vein can be identified by Holter recordings.
BACKGROUND: Although echocardiography is commonly used to evaluate cardiac function after MI, CMR may provide more accurate functional assessment but has not been adequately compared with echo. The primary study objective was to compare metrics of left ventricular volumes and global and regional function determined by cardiac magnetic resonance (CMR) and echocardiography (echo) in patients (pts) with recent myocardial infarction (MI). METHODS: To compare CMR with echo, 47 consecutive patients (pts 70% male; mean age = 66 +/- 11 years) with MI >6 wks previously and scheduled for imaging evaluation were studied by both echo and CMR within 60 min of each other. Readers were blinded to pt information. Pearson's correlation coefficient, paired t-tests, and chi-square tests were used to compare CMR and echo measures. Further comparisons were made between pts and 30 normal controls for CMR and between pts and published normal ranges for echo. RESULTS: Measures of volume and function correlated moderately well between CMR and echo (r = 0.54 to 0.75, all p < 0.001), but large and systematic differences were noted in absolute measurements. Echo underestimated left ventricular (LV) volumes (by 69 ml for end-diastolic, 35 ml for end-systolic volume, both p < 0.001), stroke volume (by 34 ml, p < 0.001), and LV ejection fraction (LVEF) (by 4 percentage point, p = 0.02). CMR was much more sensitive to detection of segmental wall motion abnormalities (p < 0.001). CMR comparisons with normal controls confirmed an increase in LV volumes, a decrease in LVEF, and preservation of stroke volume after MI. CONCLUSION: This intra subject comparison after MI found large, systematic differences between CMR and echo measures of volumes, LVEF, and wall motion abnormality despite moderate inter-modality correlations, with echo underestimating each metric. CMR also provided superior detection and quantification of segmental function after MI. Serial studies of LV function in individual patients should use the same modality.
PURPOSE: Minimalist running shoes are becoming a more popular choice for runners in the past few years. However, there is little conclusive evidence about the advantages or disadvantages of running in these shoes. Although performance benefits may exist, injury may also occur from the added stress of running without the benefit of cushioning under the foot. Bone marrow edema can be a manifestation of added stress on the foot. This study measured bone marrow edema in runners' feet before and after a 10-wk period of transitioning from traditional to minimalist running shoes. METHODS: Thirty-six experienced recreational runners underwent magnetic resonance imaging (MRI) before and after a 10-wk period. Seventeen subjects were in the control group (ran in their traditional shoes only for 10 wk), whereas the other 19 were in the experimental group (gradually transitioned to Vibram FiveFinger running shoes for 10 wk). The severity of the bone marrow edema was scored on a range of 0-4 (0 = no bone marrow edema, 4 = edema in more than 50% of the length of the bone). A score of 4 represented a stress fracture. RESULTS: Pretraining MRI scores were not statistically different between the groups. The posttraining MRI scores showed that more subjects in the Vibram group (10 of 19) showed increases in bone marrow edema in at least one bone after 10 wk of running than that in the control group (P = 0.009). CONCLUSION: Runners interested in transitioning to minimalist running shoes, such as Vibram FiveFingers, should transition very slowly and gradually to avoid potential stress injury in the foot.
BACKGROUND: Although cardiac magnetic resonance imaging (CMR) is capable of yielding extensive data in routine practice, the relative incremental prognostic value of adenosine stress perfusion, myocardial delayed enhancement (DE), and left ventricular volumes and function is unclear. METHODS AND RESULTS: We followed up 908 consecutive patients who underwent combined CMR for suspicion of coronary stenosis and/or ischemia at 2.6 ± 1.2 years, during which 101 total cardiac events occurred (all-cause death, myocardial infarction, or late revascularization). Increase in Cox proportional-hazards model global χ² (χ²) with the addition of CMR data after adjustment for clinical data defined incremental prognostic value. Cardiac magnetic resonance imaging without abnormalities had a 2.4% event rate per year (<1% cardiac death or myocardial infarction). Abnormal CMR was associated with event rates of 5.6% to 7.0% per year, varying with which and how many components were abnormal. After adjusting for the pre-CMR data (age, dyspnea, prior coronary artery disease, resting heart rate, renal disease, and diabetes mellitus, χ²:43.6, P<0.0001; C index 0.695), the addition of left ventricular ejection fraction, aortic flow, delayed enhancement, and stress perfusion data all incrementally increased χ² (55.2, 63.3, 68.0, and 68.9, respectively; all P<0.00001; C indices 0.717, 0.722, 0.747, and 0.736). The number of abnormal CMR domains both added incremental prognostic value and risk stratified patients with respect to risk of events. CONCLUSIONS: CMR analysis of ventricular volume, aortic flow, myocardial viability, and stress perfusion all add incremental value for prediction of adverse events over pre-CMR data and can be combined to further enhance prognostication. Normal combined CMR confers a low risk of subsequent cardiac events.