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Dive into the research topics where Michael B. Jorgensen is active.

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Featured researches published by Michael B. Jorgensen.


JAMA | 2008

Sodium Bicarbonate vs Sodium Chloride for the Prevention of Contrast Medium–Induced Nephropathy in Patients Undergoing Coronary Angiography: A Randomized Trial

Somjot S. Brar; Albert Yuh-Jer Shen; Michael B. Jorgensen; Adam Kotlewski; Vicken Aharonian; Natasha Desai; Michael Ree; Ahmed Ijaz Shah; Raoul J. Burchette

CONTEXT Sodium bicarbonate has been suggested as a possible strategy for prevention of contrast medium-induced nephropathy, a common cause of renal failure associated with prolonged hospitalization, increased health care costs, and substantial morbidity and mortality. OBJECTIVE To determine if sodium bicarbonate is superior to sodium chloride for preventing contrast medium-induced nephropathy in patients with moderate to severe chronic kidney dysfunction who are undergoing coronary angiography. DESIGN, SETTING, AND PATIENTS Randomized, controlled, single-blind study conducted between January 2, 2006, and January 31, 2007, and enrolling 353 patients with stable renal disease who were undergoing coronary angiography at a single US center. Included patients were 18 years or older and had an estimated glomerular filtration rate of 60 mL/min per 1.73 m(2) or less and 1 or more of diabetes mellitus, history of congestive heart failure, hypertension, or age older than 75 years. INTERVENTIONS Patients were randomized to receive either sodium chloride (n = 178) or sodium bicarbonate (n = 175) administered at the same rate (3 mL/kg for 1 hour before coronary angiography, decreased to 1.5 mL/kg per hour during the procedure and for 4 hours after the completion of the procedure). MAIN OUTCOME MEASURE The primary end point was a 25% or greater decrease in the estimated glomerular filtration rate on days 1 through 4 after contrast exposure. RESULTS Median patient age was 71 (interquartile range, 65-76) years, and 45% had diabetes mellitus. The groups were well matched for baseline characteristics. The primary end point was met in 13.3% of the sodium bicarbonate group and 14.6% of the sodium chloride group (relative risk, 0.94; 95% confidence interval, 0.55-1.60; P = .82). In patients randomized to receive sodium bicarbonate vs sodium chloride, the rates of death, dialysis, myocardial infarction, and cerebrovascular events did not differ significantly at 30 days (1.7% vs 1.7%, 0.6% vs 1.1%, 0.6% vs 0%, and 0% vs 2.2%, respectively) or at 30 days to 6 months (0.6% vs 2.3%, 0.6% vs 1.1%, 0.6% vs 2.3%, and 0.6% vs 1.7%, respectively) (P > .10 for all). CONCLUSION The results of this study do not suggest that hydration with sodium bicarbonate is superior to hydration with sodium chloride for the prevention of contrast medium-induced nephropathy in patients with moderate to severe chronic kidney disease who are undergoing coronary angiography. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT00312117.


American Heart Journal | 1994

Spontaneous coronary dissection: A cluster of cases with this rare finding

Michael B. Jorgensen; Vicken Aharonian; Prakash Mansukhani; Peter R. Mahrer

Spontaneous coronary dissection is a rare entity. It has been reported to be usually fatal, with greater than an 80% mortality rate. From April 1990 through March 1993, 10 patients had spontaneous coronary dissection. This is a significant increase in the incidence of this diagnosis, with only one prior case at this institution in 1983 (p < 0.001). All of the patients survived. Of the 10 patients, eight were women, and seven of those were premenopausal. Only one was post partum. Acute myocardial infarction was the presenting condition in nine patients. Three patients had spontaneous dissections involving two arteries. Only one patient had associated atherosclerotic coronary artery disease. Surgery was required for continued symptoms in three patients, with difficulty grafting the dissected artery in two. Nine patients have no symptoms, and one has class II angina. With aggressive medical therapy the prognosis of patients with spontaneous coronary dissection may not be as dismal as previously reported.


The American Journal of Medicine | 1992

Diagnosis and treatment of granulomatous mastitis

Michael B. Jorgensen; Donald M. Nielsen

Granulomatous mastitis is a benign inflammatory breast disease of unknown etiology. Although it is rare, it frequently presents in a manner similar to that of breast carcinoma. Surgical resection of the affected tissue has often been the method of treatment, but many patients have experienced recurrences. Corticosteroids have also been used, but the initiation of this therapy is often limited by concerns related to the presence of an infectious etiology. Presented here are two cases that demonstrate the efficacy of corticosteroids in this condition after appropriate evaluation is performed.


The Lancet | 2014

Haemodynamic-guided fluid administration for the prevention of contrast-induced acute kidney injury: the POSEIDON randomised controlled trial

Somjot S. Brar; Vicken Aharonian; Prakash Mansukhani; Naing Moore; Albert Y-J Shen; Michael B. Jorgensen; Aman Dua; Lindsay Short; Kevin Kane

BACKGROUND The administration of intravenous fluid remains the cornerstone treatment for the prevention of contrast-induced acute kidney injury. However, no well-defined protocols exist to guide fluid administration in this treatment. We aimed to establish the efficacy of a new fluid protocol to prevent contrast-induced acute kidney injury. METHODS In this randomised, parallel-group, comparator-controlled, single-blind phase 3 trial, we assessed the efficacy of a new fluid protocol based on the left ventricular end-diastolic pressure for the prevention of contrast-induced acute kidney injury in patients undergoing cardiac catheterisation. The primary outcome was the occurrence of contrast-induced acute kidney injury, which was defined as a greater than 25% or greater than 0·5 mg/dL increase in serum creatinine concentration. Between Oct 10, 2010, and July 17, 2012, 396 patients aged 18 years or older undergoing cardiac catheterisation with an estimated glomerular filtration rate of 60 mL/min per 1·73 m(2) or less and one or more of several risk factors (diabetes mellitus, history of congestive heart failure, hypertension, or age older than 75 years) were randomly allocated in a 1:1 ratio to left ventricular end-diastolic pressure-guided volume expansion (n=196) or the control group (n=200) who received a standard fluid administration protocol. Four computer-generated concealed randomisation schedules, each with permuted block sizes of 4, were used for randomisation, and participants were allocated to the next sequential randomisation number by sealed opaque envelopes. Patients and laboratory personnel were masked to treatment assignment, but the physicians who did the procedures were not masked. Both groups received intravenous 0·9% sodium chloride at 3 mL/kg for 1 h before cardiac catheterisation. Analyses were by intention to treat. Adverse events were assessed at 30 days and 6 months and all such events were classified by staff who were masked to treatment assignment. This trial is registered with ClinicalTrials.gov, number NCT01218828. FINDINGS Contrast-induced acute kidney injury occurred less frequently in patients in the left ventricular end-diastolic pressure-guided group (6·7% [12/178]) than in the control group (16·3% [28/172]; relative risk 0·41, 95% CI 0·22-0·79; p=0·005). Hydration treatment was terminated prematurely because of shortness of breath in three patients in each group. INTERPRETATION Left ventricular end-diastolic pressure-guided fluid administration seems to be safe and effective in preventing contrast-induced acute kidney injury in patients undergoing cardiac catheterisation. FUNDING Kaiser Permanente Southern California regional research committee grant.


Stroke | 2008

Racial/Ethnic differences in ischemic stroke rates and the efficacy of warfarin among patients with atrial fibrillation.

Albert Yuh-Jer Shen; Janis F. Yao; Somjot Brar; Michael B. Jorgensen; Xunzhang Wang; Wansu Chen

Background and Purpose— Warfarin reduces stroke risk in studies of predominantly white patients with atrial fibrillation (AF). Whether nonwhites also have lower rates of stroke while treated with warfarin is unclear. Methods— A multiethnic stroke-free cohort hospitalized with nonrheumatic AF was identified in a large health maintenance organization. Stroke risk factors (advanced age, diabetes, hypertension, and heart failure), warfarin use, and anticoagulation intensity were assessed. Crude ischemic stroke rates were calculated by Poisson regression for each group while using and not using warfarin. Cox proportional hazard models were constructed to assess the independent effect of race/ethnicity on ischemic stroke. Results— Between 1995 and 2000, we identified 18 867 AF hospitalizations (78.5% white, 8% black, 9.5% Hispanic, and 3.9% Asian). Over the course of 63 204 person-years follow-up (median, 3.3 years), 1226 ischemic strokes were identified. The percent-time on warfarin did not differ by race/ethnicity. The median percent-time on warfarin that international normalized ratio was 2 to 3 was 54.5% overall, but it was lower in blacks at 47.8%, whereas the other groups had a rate of ≈54%. The rate ratios (95% CI) of ischemic stroke with warfarin compared to without warfarin for whites, blacks, Hispanics, and Asians were 0.79 (0.68 to 0.90), 0.92 (0.65 to 1.30), 0.71 (0.48 to 1.05), and 0.65 (0.34 to 1.23), respectively. Conclusions— In this cohort, we did not observe a statistically significant lower rate of stroke with warfarin therapy among nonwhites (in particular blacks) with previous AF hospitalizations. The relatively small numbers of nonwhites renders our estimates less than precise and should be interpreted with caution.


Journal of The National Medical Association | 2010

Racial/Ethnic Differences in the Prevalence of Atrial Fibrillation Among Older Adults—A Cross-Sectional Study

Albert Yuh-Jer Shen; Richard Contreras; Serap Sobnosky; Ahmed Ijaz Shah; Anne Marie Ichiuji; Michael B. Jorgensen; Somjot S. Brar; Wansu Chen

BACKGROUND Atrial fibrillation affects 4% to 8% of individuals over 60 years of age based on studies of predominantly white populations, whether this is true among nonwhite individuals is not clear. This study was undertaken to define racial/ethnic differences in atrial fibrillation prevalence among a large community cohort. METHODS This is a cross-sectional study. In 2008, there were 430,317 members aged 60 years or older in a large California health maintenance organization. By searching International Classification of Diseases, Ninth Revision codes and electronic electrocardiographic archives, we identified all members in this age group with primary, nonvalvular atrial fibrillation. Race/ethnicity data were assigned using health plan enrollment, service utilization, Asian/Hispanic surname and geocoding methods, and was available for 80.5% of members (79.8% of non-atrial fibrillation and 92% of atrial fibrillation), 99% of which were white, black, Asian, or Hispanic. We assessed the age- and gender-specific atrial fibrillation prevalence rates for each racial/ethnic group. The effect of race/ethnicity on atrial fibrillation was analyzed with logistic regression methods adjusting for potential confounders. RESULTS The overall atrial fibrillation prevalence was 5.3%. Among members with assigned race/ethnicity data, the prevalence among whites, blacks, Asians, and Hispanics was 8.0%, 3.8%, 3.9%, and 3.6%, respectively. The adjusted odds ratios (95% confidence intervals) of atrial fibrillation among blacks, Asians, and Hispanics with whites as referent were 0.49 (0.47-0.52), 0.68 (0.64-0.72), and 0.58 (0.55-0.61), respectively. CONCLUSIONS Atrial fibrillation is less prevalent in older nonwhite individuals than whites. White race/ethnicity is associated with significantly greater odds for atrial fibrillation compared to blacks, Asians, and Hispanics, after adjusting for comorbidities associated with the development of atrial fibrillation.


American Journal of Cardiology | 1997

Community practice of primary angioplasty for myocardial infarction.

Anil H. Jhangiani; Michael B. Jorgensen; Adam Kotlewski; Prakash Mansukhani; Vicken Aharonian; Peter R. Mahrer

Results obtained with primary angioplasty at the community level do not duplicate the results of the published trials. Major changes in current community practice patterns are needed to achieve the success rates of the published trials.


American Heart Journal | 2003

Restenosis in intervened coronaries with hyperhomocysteinemia (RICH)

Samuel A Kojoglanian; Michael B. Jorgensen; Girma Wolde-Tsadik; Raoul J. Burchette; Vicken Aharonian

BACKGROUND Controversy exists regarding the contribution made by elevated serum homocysteine evels in raising the risk of restenosis after percutaneous coronary interventions. The objective of this study was to determine whether elevated homocysteine evels increase the risk of restenosis. METHODS Two hundred and two consecutive patients undergoing percutaneous coronary intervention with stents on previously nonintervened native coronary arteries were eligible for enrollment in the study. Before the percutaneous coronary intervention, a fasting serum homocysteine evel was drawn. Patients were followed-up by their primary cardiologists for recurrence of symptoms. Those patients who had a recurrence of anginal symptoms consistent with clinical restenosis were referred for a repeat angiogram. All other patients were followed-up medically. The homocysteine evels of the patients who had repeat angiography for recurrent symptoms were compared to those who were followed-up medically. RESULTS Age, stent ength, stent diameter, and homocysteine evels were all associated with an increased risk of restenosis in the univariate analysis. In the multiple ogistic regression model, the only variable that remained significant in relation to an increased risk of restenosis was homocysteine. There was a significant difference in the mean homocysteine evels between the restenosis group (13.7 micromol/L) and those without restenosis (9.6 micromol/L; P <.0001). A homocysteine evel > or =11.1 micromol/L was identified as the best threshold for an increased risk of restenosis with a sensitivity of 75.0% and specificity of 76.9% (OR 6.5, CI 2.3-18.6; P =.0004). CONCLUSION This study demonstrates that elevated homocysteine evels strongly correlate with an increased risk of restenosis.


Catheterization and Cardiovascular Interventions | 1999

Primary angioplasty for acute myocardial infarction resulting from the simultaneous occlusion of two major coronary arteries

Albert Yuh-Jer Shen; Prakash Mansukhani; Vicken Aharonian; Michael B. Jorgensen

Primary angioplasty for acute myocardial infarction is frequently performed. Not uncommonly, more than one occluded artery may be present. Usually only one is an acute event, the others being chronic occlusions. We encountered a patient who presented with two simultaneous occlusions; both were successfully recanalized. We discuss some observations that assisted us in devising our treatment strategy. Cathet. Cardiovasc. Intervent. 47:203–207, 1999.


American Journal of Cardiology | 1998

Predictors of Survival After Coronary Bypass Grafting in Patients With Total Occlusion of the Left Main Coronary Artery

Albert Yuh-Jer Shen; Ravi Jandhyala; Christopher Ruel; Robert J. Lundstrom; Michael B. Jorgensen

Twenty-three patients with angiographically documented total occlusion of the left main coronary artery were retrospectively identified. Statistical analysis suggests that poor right-to-left collaterals and the presence of concurrent significant right coronary artery disease were weakly associated with decreased survival after bypass surgery.

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Somjot Brar

Columbia University Medical Center

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