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ABSTRACT: To evaluate the association of exercise and knee-bending activities with magnetic resonance imaging (MRI)-based knee cartilage T2 relaxation times and morphologic abnormalities in asymptomatic subjects from the Osteoarthritis Initiative, with or without osteoarthritis (OA) risk factors.
We studied 128 subjects with knee OA risk factors and 33 normal control subjects ages 45-55 years, with a body mass index of 18-27 kg/m(2) and no knee pain. Subjects were categorized according to exercise level, using the leisure activity component of the Physical Activity Scale for the Elderly, and by self-reported frequent knee-bending activities. Two radiologists graded the cartilage of the right knee on MR images, using the Whole-Organ MRI Score (WORMS). Cartilage was segmented, and compartment-specific T2 values were calculated. Differences between the exercise groups and knee-bending groups were determined using multiple linear and logistic regression models.
Among subjects with risk factors for knee OA, light exercisers had lower T2 values compared with sedentary and moderate/strenuous exercisers. When the sexes were analyzed separately, female moderate/strenuous exercisers had higher T2 values compared with sedentary individuals and light exercisers. Subjects without risk factors displayed no significant differences in T2 values according to exercise level. However, frequent knee-bending activities were associated with higher T2 values in both subjects with OA risk factors and those without OA risk factors and with more severe cartilage lesions in the group with risk factors.
In subjects at risk of knee OA, light exercise was associated with low T2 values, whereas moderate/strenuous exercise in women was associated with high T2 values. Higher T2 values and WORMS grades were also observed in frequent knee-benders, suggesting greater cartilage degeneration in these individuals.
Arthritis & Rheumatism 05/2011; 63(8):2248-56. · 7.87 Impact Factor
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ABSTRACT: Fluctuations in pain in patients with knee osteoarthritis (OA) are common, but risk factors for pain fluctuation are poorly understood. To best identify the structural causes of fluctuations, multiple assessments of pain status and structural lesions are needed. This study was undertaken to determine whether pain resolution is accompanied by diminution of lesions in patients with knee OA.
Subjects in the Multicenter Osteoarthritis Study were queried about their knee pain by interview, and knees were assessed by magnetic resonance imaging at the baseline and 15-month and 30-month clinic visits. For those knees in which pain fluctuation was identified over 3 clinic visits, the relationship of bone marrow lesions (BMLs), synovitis, and effusion to frequent knee pain and severity of knee pain was examined using conditional logistic regression analyses.
Included in the analysis were 570 subjects with knee OA (651 knees). When the BML score changed from 0 to 1, 2, 3, 4, 5-6, and 7-18 over 2 consecutive clinic visits, the odds ratios (ORs) for frequent knee pain were 1.2, 1.2, 1.5, 2.2, 2.4, and 2.5, respectively (P for trend = 0.006). The corresponding ORs were 1.5, 1.5, and 2.4 when the synovitis score changed from 0 to 1, 2, and 3-6, respectively (P for trend = 0.045). No significant association was found between the effusion score and frequent knee pain. Diminishing size of BMLs was associated with resolution of knee pain (P for trend = 0.007). Similar associations were also observed between these structural lesions and the severity of knee pain.
Changes in BMLs and synovitis are associated with fluctuations in knee pain in patients with knee OA. Pain resolution occurs more frequently when BMLs become smaller.
Arthritis & Rheumatism 03/2011; 63(3):691-9. · 7.87 Impact Factor
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ABSTRACT: To determine whether an additional follicle-stimulating hormone (FSH) bolus administered at the time of the human chorionic gonadotropin (hCG) trigger can improve the developmental competence of the oocyte.
Randomized, double-blind, placebo-controlled, clinical trial.
Academic medical center.
Women undergoing a long agonist suppression in vitro fertilization (IVF) protocol for treatment of infertility.
FSH bolus at time of hCG trigger versus placebo.
Primary outcome; fertilization; secondary outcomes: oocyte recovery, implantation rate, and clinical and ongoing pregnancy/live birth rates.
A total of 188 women (mean age: 36.2 years; range: 25 to 40 years) were randomized. Fertilization (2PN/#oocyte) was statistically significantly improved in the treatment arm (63% vs. 55%) as was the likelihood of oocyte recovery (70% vs. 57%). There was no statistically significant difference in clinical pregnancy rate (56.8% vs. 46.2%) or ongoing/live birth rate (51.6% vs. 43.0%).
Improvements in IVF success rates have largely been due to optimization of embryo culture and stimulation protocols; less attention has been directed toward methods to improve induction of final oocyte maturation. This was the first randomized, double-blind, placebo-controlled trial to modify the ovulation trigger to improve oocyte competence, as demonstrated by the statistically significant improvement in fertilization.
Fertility and sterility 02/2011; 95(5):1655-60. · 3.97 Impact Factor
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ABSTRACT: Stroke is a major cause of death and leading cause of disability in the United States. To maximize a stroke patient's chances of receiving thrombolytic treatment for acute ischemic stroke, it is important to improve prehospital recognition of stroke. However, it is known from published reports that emergency medical dispatchers (EMDs) using Card 28 of the Medical Priority Dispatch System protocols recognize stroke poorly. Therefore, to improve EMD's recognition of stroke, the National Association of Emergency Medical Dispatchers recently designed a new diagnostic stroke tool (Cincinnati Stroke Scale -CSS) to be used with Card 28. The objective of this study is to determine whether the addition of CSS improves diagnostic accuracy of stroke triage.
This prospective experimental study will be conducted during a one-year period in the 911 call center of Santa Clara County, CA. We will include callers aged ≥ 18 years with a chief complaint suggestive of stroke and second party callers (by-stander or family who are in close proximity to the patient and can administer the tool) ≥ 18 years of age. Life threatening calls will be excluded from the study. Card 28 questions will be administered to subjects who meet study criteria. After completion of Card 28, CSS tool will be administered to all calls. EMDs will record their initial assessment of a cerebro-vascular accident (stroke) after completion of Card 28 and their final assessment after completion of CSS. These assessments will be compared with the hospital discharge diagnosis (ICD-9 codes) recorded in the Office of Statewide Health Planning and Development (OSHPD) database after linking the EMD database and OSHPD database using probabilistic linkage. The primary analysis will compare the sensitivity of the two stroke protocols using logistic regression and generalizing estimating equations to account for clustering by EMDs. To detect a 15% difference in sensitivity between the two groups with 80% power, we will enroll a total of 370 subjects in this trial.
A three week pilot study was performed which demonstrated the feasibility of implementation of the study protocol.
BMC Neurology 01/2011; 11:14. · 2.17 Impact Factor
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ABSTRACT: We characterize changes in review quality by individual peer reviewers over time.
Editors at a specialty journal in the top 11% of Institute of Scientific Information journals rated the quality of every review, using a validated 5-point quality score. Linear mixed-effect models were used to analyze rating changes over time, calculating within-reviewer trends plus predicted slope of change in score for each reviewer. Reviewers at this journal have been shown comparable to those at other journals.
Reviews (14,808) were performed by 1,499 reviewers and rated by 84 editors during the 14-year study. Ninety-two percent of reviewers demonstrated very slow but steady deterioration in their scores (mean -0.04 points [-0.8%] per year). Rate of deterioration was unrelated to duration of reviewing but moderately correlated with mean reviewer quality score (R=0.52). The mean score of each reviewer's first 4 reviews predicted subsequent performance with a sensitivity of 75% and specificity of 47%. Scores of the group stayed constant over time despite deterioration because newly recruited reviewers initially had higher mean quality scores than their predecessors.
This study, one of few tracking expert performance longitudinally, demonstrates that most journal peer reviewers received lower quality scores for article assessment over the years. This could be due to deteriorating performance (caused by either cognitive changes or competing priorities) or, to a partial degree, escalating expectations; other explanations were ruled out. This makes monitoring reviewer quality even more crucial to maintain the mission of scientific journals.
Annals of emergency medicine 11/2010; 57(2):141-8. · 4.23 Impact Factor
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ABSTRACT: OBJECTIVE: Fluctuations in pain among persons with knee osteoarthritis are both common and risk factors for pain fluctuation are poorly understood. To best identify structural causes of fluctuations, multiple assessments of pain status and structural lesions are needed. Therapeutic evidence may be best gleaned if pain resolution is accompanied by diminution of lesions. METHODS: Subjects in the Multicenter Osteoarthritis Study were queried about their knee pain by interview and had knee magnetic resonance imaging at baseline, 15-month, and 30-month clinic visits. Among the knees experiencing pain fluctuation over three clinic visits we examined the relation of bone marrow lesions (BMLs), synovitis, and effusion to frequent knee pain and pain severity using conditional logistic regression. RESULTS: Included in the analysis were 570 subjects (651 knees). When the BML score changed from 0 to 1, 2, 3, 4, 5-6 and 7-18, the odds ratios (OR) for frequent knee pain were 1.2, 1.2, 1.5, 2.2, 2.4, and 2.5, respectively (P for trend=0.006). The corresponding ORs were 1.5, 1.5, and 2.4 when synovitis score changed from 0 to 1, 2, and 3-6 (P for trend=0.045). No significant association was found between effusion and frequent knee pain. Diminishing size of BMLs was associated with resolution of knee pain (P=0.007). Similar associations were also observed between these structural lesions and knee pain severity. CONCLUSION: Changes of BMLs and synovitis are associated with the fluctuation of knee pain. Pain resolution occurs more frequently when BMLs become smaller.
Arthritis & Rheumatism 11/2010; · 7.87 Impact Factor
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ABSTRACT: To investigate the association between hormone levels from individual follicles and fertilization outcome among patients undergoing intracytoplasmic sperm injection (ICSI). Differences in concentrations of selected sex steroids and pituitary hormones in individual follicular aspirates between oocytes that fertilize successfully, those that fail to fertilize, and those that degenerate with ICSI were examined.
Prospective cohort study.
Academic medical center.
Women undergoing ovarian stimulation and ICSI.
Follicular fluid was sampled by transvaginal ultrasound-guided aspiration of the hyperstimulated ovary. Each follicle was individually aspirated and collected. Intracytoplasmic sperm injection and subsequent embryo culture were performed using standard laboratory technique. Follicular fluid gonadotropin and steroid hormone levels were measured by immunoassay.
Oocyte fertilization outcome with ICSI.
Oocytes that fertilized normally came from follicles with higher estradiol (adjusted odds ratio [AOR]=1.28) and testosterone (AOR=1.35) concentrations compared with those that degenerated with ICSI. Oocytes that fertilized normally also came from follicles with higher estradiol (AOR=1.14) and progesterone (AOR=1.09) concentrations compared with those that failed to fertilize.
The hormonal profile of the follicular fluid yielding a degenerative egg or an egg that fails to fertilize is different from that resulting in normal fertilization. Higher follicular fluid estradiol may be a marker for oocytes that will fertilize normally with ICSI.
Fertility and sterility 08/2009; 94(3):952-7. · 3.97 Impact Factor
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ABSTRACT: Serrated polyps of the colorectum are a histologically and genetically heterogeneous group of lesions, which include classic hyperplasic polyps, sessile serrated adenomas (SSAs), and traditional serrated adenomas. Accumulating evidence suggests that they may have different malignancy potentials. This study sought to determine the association between the presence of large serrated colorectal polyps and synchronous advanced colorectal neoplasia.
Among 4,714 asymptomatic subjects who underwent screening colonoscopy, cases of advanced colorectal neoplasia (tubular adenoma > or =1 cm, adenoma with any villous histology, adenoma with carcinoma in situ / high-grade dysplasia, or invasive adenocarcinoma) were compared with controls without advanced neoplasia with respect to candidate predictors, including age, sex, family history of colorectal cancer, body mass index, the presence and number of small tubular adenomas (<1 cm), the presence of multiple small serrated polyps (<1 cm), and the presence of large serrated polyps (> or =1 cm). Independent predictors of advanced neoplasia were determined by multivariate logistic regression analysis.
Among 467 cases and 4,247 controls, independent predictors of advanced colorectal neoplasia were increasing age (odds ratio (OR)=4.51; 95% confidence interval (CI), 1.43-14.3; P=0.01 for subjects > or =80 years vs. 50-54 years of age); non-advanced tubular adenomas (OR=2.33; 95% CI 1.37-3.96, P=0.0017 for 3 or more); and large serrated polyps (OR=3.24; 95% CI 2.05-5.13, P<0.0001). In total, 109 subjects (2.3% of the study population) had large serrated polyps. Right- and left-sided large serrated polyps had a similar association with advanced colorectal neoplasia (OR=3.38 vs. 2.66, P=0.62).
Large serrated polyps are strongly and independently associated with synchronous advanced colorectal neoplasia. Our results suggest that large serrated polyps may be a marker for advanced colorectal neoplasia. Further studies are needed to determine whether the association with advanced neoplasia differs among subsets of serrated polyps, particularly SSAs and classic hyperplastic polyps.
The American Journal of Gastroenterology 02/2009; 104(3):695-702. · 7.28 Impact Factor
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David T Felson,
Michael C Nevitt,
Mei Yang,
Margaret Clancy,
Jingbo Niu,
James C Torner,
C Elizabeth Lewis,
Piran Aliabadi,
Burton Sack, Charles McCulloch,
Yuqing Zhang
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ABSTRACT: Progression of knee osteoarthritis (OA) has typically been assessed in the medial tibiofemoral (TF) compartment on the anteroposterior (AP) or posteroanterior (PA) view. We propose a new approach using multiple views and compartments that is likely to be more sensitive to change and reveals progression throughout the knee.
We tested our approach in the Multicenter Osteoarthritis Study, a study of persons with OA or at high risk of disease. At baseline and 30 months, subjects provided PA (fixed flexion without fluoro) and lateral weight-bearing knee radiographs. Paired radiographs were read by 2 readers who scored joint space (JS) using a 0-3 atlas-based scale. When JS narrowed but narrowing did not reach a full grade on the scale, readers used half-grades. Change was scored in medial and lateral TF compartments on both PA and lateral views and in the patellofemoral (PF) joint on lateral view. A knee showed progression when there was at least a half-grade worsening in JS width in any compartment at followup. Disagreements were adjudicated by a panel of 3 readers. To validate progression, we tested definitions for TF progression to see if malalignment on long-limb radiographs at baseline (>or=3 degrees malaligned in any direction with nonmalaligned knees being reference) increased risk of progression. A valid definition of progression would show that malalignment strongly predicted progression.
We studied 842 knees with either Kellgren-Lawrence grade>or=2 or PF OA at baseline in 606 subjects (age range 50-79 yrs, mean 63.9 yrs; 66.6% women). Mean body mass index was 31.9, and 32.8% of knees had frequent knee pain at baseline. Of these, 500 knees (59.4%) showed progression. Of the 500, 75 (15%) had progression only in the PF joint, while the remainder had progression in the TF joint. Malalignment increased the risk of overall progression in TF joint and increased the risk of half-grade progression, suggesting that half-grade progression had validity.
PA and lateral views obtained in persons at high risk of OA progression can produce a cumulative incidence of progression above 50% at 30 months. Keys to increasing the yield include imaging PF and lateral compartments, using semiquantitative scales designed to detect change, and examining more than one radiographic view.
The Journal of Rheumatology 09/2008; 35(10):2047-54. · 3.69 Impact Factor
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ABSTRACT: Evolution of intracranial aneurysmal disease is known to be related to hemodynamic forces acting on the vessel wall. Low wall shear stress (WSS) has been reported to have a negative effect on endothelial cells normal physiology and may be an important contributor to local remodeling of the arterial wall and to aneurysm growth and rupture.
Seven patient-specific models of intracranial aneurysms were constructed using MR angiography data acquired at two different time points (mean 16.4+/-7.4 months between the two time points). Numeric simulations of the flow in the baseline geometries were performed to compute WSS distributions. The lumenal geometries constructed from the two time points were manually coregistered, and the radial displacement of the wall was calculated on a pixel-by-pixel basis. This displacement, corresponding to the local growth of the aneurysm, was compared to the time-averaged wall shear stress (WSS TA) through the cardiac cycle at that location. For statistical analysis, radial displacement was considered to be significant if it was larger than half of the MR pixel resolution (0.3 mm).
Mean WSS TA values obtained for the areas with a displacement smaller and greater than 0.3 mm were 2.55+/-3.6 and 0.76+/-1.5 Pa, respectively (P<0.001). A linear correlation analysis demonstrated a significant relationship between WSS TA and surface displacement (P<0.001).
These results indicate that aneurysm growth is likely to occur in regions where the endothelial layer lining the vessel wall is exposed to abnormally low wall shear stress.
Stroke 08/2008; 39(11):2997-3002. · 5.73 Impact Factor
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Charles McCulloch
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ABSTRACT: After a brief review of the use of latent variables to accommodate the correlation among multiple outcomes of mixed types, through theoretical and numerical calculation, the consequences of such a construction are quantified. The effects of including latent variables on marginal inference in these models are contrasted with the situation for jointly normal outcomes. A simulation study illustrates the efficiency and reduction in bias gains possible in using joint models, and analysis of an example from the field of osteoarthritis illustrates potential practical differences.
Statistical Methods in Medical Research 03/2008; 17(1):53-73. · 2.44 Impact Factor
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ABSTRACT: The goal was to determine the association between cardiovascular risk factors and microalbuminuria in a nationally representative sample of adolescents and to determine whether being overweight modifies this association.
We analyzed cross-sectional data from the National Health and Nutrition Examination Survey (1999-2004) for 2515 adolescents 12 to 19 years of age. Cardiovascular risk factors included abdominal obesity, impaired fasting glucose, diabetes mellitus, insulin resistance, high triglyceride levels, low high-density lipoprotein cholesterol levels, hypertension, smoking, and the metabolic syndrome. Microalbuminuria was defined as a urinary albumin/creatinine ratio of 30 to 299 mg/g in a random morning sample. Overweight was defined as BMI of > or = 95th percentile, according to the Centers for Disease Control and Prevention 2000 growth charts.
Microalbuminuria was present in 8.9% of adolescents. The prevalence of microalbuminuria was higher among nonoverweight adolescents than among overweight adolescents. The median albumin/creatinine ratio decreased with increasing BMI z scores. The association of microalbuminuria with cardiovascular risk factors differed according to BMI category. Among nonoverweight adolescents, microalbuminuria was not associated with any cardiovascular disease risk factor except for overt diabetes mellitus. Among overweight adolescents, however, microalbuminuria was associated with impaired fasting glucose, insulin resistance, hypertension, and smoking, as well as diabetes mellitus.
For the majority of adolescents, microalbuminuria is not associated with cardiovascular risk factors. Among overweight adolescents, however, microalbuminuria is associated with cardiovascular risk factors. The prognostic importance of microalbuminuria in overweight and nonoverweight adolescents with regard to future cardiovascular and renal disease needs to be defined in prospective studies conducted specifically in children.
PEDIATRICS 01/2008; 121(1):37-45. · 4.47 Impact Factor
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ABSTRACT: To determine whether older women who maintain optimal cognitive function into old age differ from those who experience minor cognitive decline typically associated with normal aging.
Prospective cohort study.
The Study of Osteoporotic Fractures.
Nine thousand seven hundred four older women.
A modified Mini-Mental State Examination (mMMSE) was performed at baseline and Years 6, 8, 10, and 15. Random-effects regression was used to classify subjects as cognitive maintainers (slope>/=0), minor decliners (slope < 0 but > lowest tertile), or major decliners (slope <or= lowest tertile). Stepwise logistic regression was used to identify factors most predictive of being a cognitive maintainer versus a minor decliner (excluding major decliners).
Women had a mean age of 72 at baseline and 85 at follow-up. Nine percent maintained optimal cognitive function, 58% experienced minor decline, and 33% experienced major decline. Most factors differed progressively over the three cognitive groups. After adjustment for key confounders, odds ratios for factors most predictive of being a cognitive maintainer as opposed to minor decliner were 1.9 (95% confidence interval (CI)=1.2-2.9) for lack of diabetes mellitus, 1.2 (95% CI=1.0-1.4) for lack of hypertension, 1.7 (95% CI=1.3-2.3) for lack of smoking, 1.2 (95% CI=1.1-1.5) for moderate alcohol consumption, 1.4 (95% CI=1.1-1.7) for lack of difficulty with instrumental activities of daily living, and 1.2 (95% CI=1.0-1.4) for lack of low social network.
Almost 10% of older women maintained optimal cognitive function into old age. Cognitive maintainers were less likely to have comorbid medical conditions, less likely to have difficulty with daily activities or poor social networks, and more likely to engage in healthy behaviors than minor cognitive decliners.
Journal of the American Geriatrics Society 03/2007; 55(2):259-64. · 3.74 Impact Factor
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ABSTRACT: House staff work-hour regulations have required residency programs to reengineer inpatient services. However, few data describe how house staff workload on a patient's day of admission or on subsequent hospital days influences patient outcomes.
Retrospective cohort analysis of 5742 adults admitted to an academic general medical service between July 1, 1998, and June 30, 2001.
After multivariate risk adjustment for patient severity and other structural factors, we found that 2 different measures of house staff workload significantly affected patient outcomes. House staff workload increases on the day of admission, defined as each additional team admission on a patient's admission day, increased length of stay (difference, 3.09%; 95% confidence interval [CI], 2.22%-3.96%), total costs (difference, 2.31%; 95% CI, 1.29%-3.33%), and risk of inpatient mortality (odds ratio, 1.09; 95% CI, 1.02-1.15). Patients had an even higher mortality risk when more than 9 patients were admitted to their team on their admission day. In contrast, house staff workload increases during the patient's entire stay, defined as every additional patient added to the team average census, reduced length of stay (difference, -5.30%; 95% CI, -4.54% to -6.07%) and total costs (difference, -5.11%; 95% CI, -4.20% to -6.00%). Reductions in length of stay and costs were most striking when the team average census exceeded 15 patients.
Our findings suggest that higher house staff workload on admitting days-when fewer backup resources are available-increases resource use and may increase inpatient mortality. Conversely, a higher average team census was associated with reduced resource use, perhaps reflecting service-level adaptations to workload. Future studies should confirm these findings in larger trials.
Archives of Internal Medicine 02/2007; 167(1):47-52. · 11.46 Impact Factor
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New England Journal of Medicine 12/2005; 353(21):2301-3; author reply 2301-3. · 53.30 Impact Factor
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ABSTRACT: The coronary artery calcium (CAC) score is an independent predictor of coronary heart disease. We sought to combine information from the CAC score with information from conventional cardiac risk factors to produce post-test risk estimates, and to determine whether the score may add clinically useful information.
We measured the independent cross-sectional associations between conventional cardiac risk factors and the CAC score among asymptomatic persons referred for non-contrast electron beam computed tomography. Using the resulting multivariable models and published CAC score-specific relative risk estimates, we estimated post-test coronary heart disease risk in a number of different scenarios.
Among 9341 asymptomatic study participants (age 35-88 years, 40% female), we found that conventional coronary heart disease risk factors including age, male sex, self-reported hypertension, diabetes and high cholesterol were independent predictors of the CAC score, and we used the resulting multivariable models for predicting post-test risk in a variety of scenarios. Our models predicted, for example, that a 60-year-old non-smoking non-diabetic women with hypertension and high cholesterol would have a 47% chance of having a CAC score of zero, reducing her 10-year risk estimate from 15% (per Framingham) to 6-9%; if her score were over 100, however (a 17% chance), her risk estimate would be markedly higher (25-51% in 10 years). In low risk scenarios, the CAC score is very likely to be zero or low, and unlikely to change management.
Combining information from the CAC score with information from conventional risk factors can change assessment of coronary heart disease risk to an extent that may be clinically important, especially when the pre-test 10-year risk estimate is intermediate. The attached spreadsheet makes these calculations easy.
BMC Medicine 09/2004; 2:31. · 6.03 Impact Factor
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ABSTRACT: We reviewed smoking shown in a random sample of major motion pictures from 1950 through 2002. Smoking incidents declined from 10.7 incidents per hour in 1950 to a minimum of 4.9 in 1980-1982 but increased to 10.9 in 2002. Despite declining tobacco use and increasing public understanding of the dangers of smoking in the real world, smoking in movies has returned to levels observed in 1950, when smoking was nearly twice as prevalent in reality as it was in 2002.
American Journal of Public Health 03/2004; 94(2):261-3. · 3.93 Impact Factor
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ABSTRACT: Population studies have identified the presence of bundle branch block (BBB) as a risk factor for increased mortality in patients with known cardiac disease. It is unknown how chronic ventricular dyssynchrony resulting solely from conduction delay affects ventricular function.
Subjects were retrospectively identified from the University of California, San Francisco, electrocardiogram database with QRS prolongation. Subjects who had no evidence of heart disease and had baseline and serial studies evaluating ongoing risk of coronary artery disease status and left ventricular function were followed over time. Documentation of a minimum of 2 serial evaluations of cardiac status were present in a total of 51/176 (20%) subjects with isolated BBB who constitute the study population. After a mean follow-up of 52 +/- 45 months-adjusting for differences due to age, sex, the presence of hypertension, hyperlipidemia, and diabetes mellitus-left ventricular ejection fraction diminished by -7.3 +/- 12% per year in the isolated left BBB cohort versus -1.9 +/- 4% in isolated right BBB cohort and -1.1 +/- 3% reduction in the isolated nonspecific intraventricular conduction delay cohort (P =.019).
Left bundle branch block itself may be a cause of ventricular dysfunction.
Journal of Cardiac Failure 05/2003; 9(2):87-92. · 3.66 Impact Factor
