in response to “a prospective, randomized trial of an emergency department observation unit for...
TRANSCRIPT
Correspondence
in any way related to the subject of this article that might createany potential conflict of interest. The authors state that no suchrelationships exist. See the Manuscript Submission Agreement inthis issue for examples of specific conflicts covered by this state-ment.
1. Huang WT, Lin HJ, Li YS, et al. Man with progressive dyspnea. AnnEmerg Med. 2008;52:492,495.
2. Goldhaber SZ, Hennekens CH, Evans DA, et al. Factors associatedwith correct antemortem diagnosis of major pulmonary embolism.Am J Med. 1982;73:822-826.
3. Rubinstein I, Murray D, Hoffstein V. Fatal pulmonary emboli inhospitalized patients. Arch Intern Med. 1988;148:1425-1426.
4. Morgenthaler T, Ryu J. Clinical characteristics of fatal pulmonaryembolism in a referral hospital. Mayo Clin Proc. 1995;70:417-424.
5. Pineda LA, Hathwar VS, Grant BJ. Clinical suspicion of fatalpulmonary embolism. Chest. 2001;120:791-795.
In reply:We appreciate the clarification from Bouzas-Mosquera and
colleagues. The correct antemortem diagnosis rate of fatalpulmonary embolism had improved gradually in the past 50years. In the 1950s, Uhland and Goldberg showed that only 11to 12% of patients with pulmonary embolism received correctdiagnoses before death.1 With advent of better diagnostic tests,there was an improvement in diagnostic accuracy. Goldhaberand colleagues reported a 30% rate of correct antemortemdiagnosis in a study done from 1973 to 1977.2 In the followingdecade, there was no increase in antemortem diagnosis rate offatal pulmonary embolism. Rubistein et al reported a 32% rateof correct antemortem diagnosis of pulmonary emboilsm from1980 to 1984.3 More recently, Morgenthaler and Ryu showedno change in the diagnostic accuracy (32%) of fatal pulmonaryembolism in an autopsy study done from 1985 to 1989.4 Thestudy by Pineda et al, which was performed from 1991 to 1996,found a higher antemortem diagnosis rate (45%) in patients offatal pulmonary embolism.5 The high index of suspicion that isbeing encouraged in teaching hospitals coupled with the delugeof articles that have been published in medical journals recentlyor an increase in the documentation may have contributed tothis improving trend.5 When the aggregate of the 4 similarstudies from 1973 to 1996 were included,2-5 65.4% patients offatal pulmonary embolism were not correctly diagnosed beforedeath. It was reasonable to assume that the misdiagnosis rate inthe emergency department was higher than 65.4% (up to twothirds). The correct clinical diagnosis of pulmonary embolismwas made significantly less frequently in patients who hadreceived a diagnosis of acute myocardial infarction, coronaryartery disease or chronic obstructive pulmonary disease.5
Antemortem clinical suspicion of pulmonary embolism was alsolower (18%) in patients with heart disease.6 A concomitantdiagnosis of chronic obstructive pulmonary disease, coronaryartery disease, or other heart disease appeared to distractphysicians from suspecting pulmonary embolism because of the
overlap in symptoms such as dyspnea, chest pain orVolume , . : May
hypotension. In these patients, higher level of suspicion shouldbe kept in mind. Paterson and Schwartzman commented thatspiral computed tomography can safely replace pulmonaryangiography in the workup of suspected pulmonary embolism,7
as we used in this patient.
Wei-Ta Huang, MDHung-Jung Lin, MDChun-Fu Hsieh, MDDepartment of Emergency MedicineChi-Mei Medical CenterYung Kang City, Tainan, Taiwan
doi:10.1016/j.annemergmed.2008.12.015
Funding and support: By Annals policy, all authors are required todisclose any and all commercial, financial, and other relationshipsin any way related to the subject of this article that might createany potential conflict of interest. The authors have stated that nosuch relationships exist. See the Manuscript Submission Agree-ment in this issue for examples of specific conflicts covered by thisstatement.
1. Uhland H, Goldberg LM. Pulmonary embolism: a commonly missedclinical entity. Dis Chest. 1964;45:533-536.
2. Goldhaber SZ, Hennekens CH, Evans DA, et al. Factors associatedwith correct antemortem diagnosis of major pulmonary embolism.Am J Med. 1982;73:822-826.
3. Rubinstein I, Murray D, Hoffstein V. Fatal pulmonary emboli inhospitalized patients. Arch Intern Med. 1988;148:1425-1426.
4. Morgenthaler T, Ryu J. Clinical characteristics of fatal pulmonaryembolism in a referral hospital. Mayo Clin Proc. 1995;70:417-424.
5. Pineda LA, Hathwar VS, Grant BJ. Clinical suspicion of fatalpulmonary embolism. Chest. 2001;120:791-795.
6. Pulido T, Aranda A, Zevallos MA, et al. Pulmonary embolism as acause of death in patients with heart disease: an autopsy study.Chest. 2006;129:1282-1287
7. Paterson DI, Schwartzman K. Strategies incorporating spiral CT forthe diagnosis of acute pulmonary embolism: a cost-effectivenessanalysis. Chest. 2001;119:1791-1800.
In Response to “A Prospective, Randomized Trialof an Emergency Department Observation Unitfor Acute Onset Atrial Fibrillation”
To the Editor:This interesting study compares emergency department (ED)
observation unit treatment and inhospital treatment for patientspresenting with �48h of atrial fibrillation.1 The authors suggestthis study is relevant due to the importance of cost effectivemanagement of atrial fibrillation–the groups had similaroutcomes except for length of stay, and the assumption is thatcosts are reduced by shorter stays. However, neither length ofstay nor cost were specified as primary or secondary outcomes.The primary endpoint “conversion to sinus rhythm or ratecontrol” is not specifically addressed; the assumption is that all
patients were rate-controlled.Annals of Emergency Medicine 695
Correspondence
One notable difference between the 2 groups was use ofdirect-current cardioversion: 51% ED observation unit versus23%. This suggests that direct-current cardioversion is effectivefor rhythm control and perhaps contributed to shorter stays.However, the clinical relevance of restoring sinus rhythm isdebatable, even for patients with �48h duration of atrialfibrillation.
In this study, thromboembolism prophylaxis was provided tothe inpatient group but not to the ED observation unit group.American Heart Association guidelines make a Class Irecommendation for anticoagulation in all patients with atrialfibrillation except those with lone atrial fibrillation orcontraindications.2 Specifically for patients undergoingcardioversion within 48h of onset, there is a Class IIarecommendation to anticoagulate based on the patient’s risk ofthromboembolism. Clinical prediction rules such as CHADS2
(Congestive heart failure, Hypertension, Age, Diabetes, Stroke/TIA [2 points]) are very useful for risk-stratification:3 almosthalf the patients in each arm of this study would have at leastone point towards CHADS2 (40/75 ED observation unity and34/78 inhospital, data on transient ischemic attacks notprovided). Additionally, 63% of patients here had a priorhistory of atrial fibrillation and would be classified asparoxysmal atrial fibrillation. The American Heart Associationguidelines recommend against antiarrhythmic therapy inpatients with brief or minimally symptomatic recurrences ofparoxysmal atrial fibrillation. Rate control and prevention ofthromboembolism are considered appropriate for bothsymptomatic and asymptomatic paroxysmal atrial fibrillation.The RACE (RAte Control versus Electrical cardioversion forpersistent atrial fibrillation) and AFFIRM (Atrial FibrillationFollow-up Investigation of Rhythm Management) studiesreferenced by the authors provide high-quality evidence fornoninferiority of rate control over rhythm control.4,5 Whilethese studies did not specifically look at atrial fibrillation �48h,31.8% of patients in AFFIRM had a “duration of qualifyingatrial fibrillation” �2 days. In the RACE trial, the “duration ofcurrent episode of atrial fibrillation” ranged from 1 to 399 days.
The similar outcomes at 6 months may perhaps be due tostarting anticoagulation at a later stage. It is probably areasonable assumption that management styles of the inpatientand outpatient cardiologists were similar. Thus the 6-monthoutcomes may be a reflection of the cardiologists’ care ratherthan the ED observation unit.
An alternate strategy for reducing cost may be to pursue ratecontrol in the ED observation unit with initiation of aspirin/Coumadin using CHADS2 scores. These patients may then bedischarged on anticoagulation with close follow-up. Indeed, 107screened patients in this study were discharged prior toenrollment and such a strategy was perhaps pursued in these.
The important inference from this study is that there may bea population of patients with atrial fibrillation that can bemanaged without hospitalization. Identifying this group may
help reduce the burden of rising health care costs.696 Annals of Emergency Medicine
Nikhil Goyal, MDDepartment of Emergency MedicineHenry Ford HospitalDetroit, MI
Deepak K. Gupta, MDDivision of CardiologyNorthwestern University’s Feinberg School of MedicineChicago, IL
doi:10.1016/j.annemergmed.2008.11.028
Funding and support: By Annals policy, all authors are required todisclose any and all commercial, financial, and other relationshipsin any way related to the subject of this article that might createany potential conflict of interest. The authorshave stated that nosuch relationships exist. See the Manuscript Submission Agree-ment in this issue for examples of specific conflicts covered by thisstatement.
1. Decker WW, Smars PA, Vaidyanathan L, et al. A prospective,randomized trial of an emergency department observation unit foracute onset atrial fibrillation. Ann Emerg Med. 2008;52:322-328.
2. Fuster V, Ryden LE, Cannom DS, et al. ACC/AHA/ESC 2006Guidelines for the Management of Patients with Atrial Fibrillation: areport of the American College of Cardiology/American HeartAssociation Task Force on Practice Guidelines and the EuropeanSociety of Cardiology Committee for Practice Guidelines (WritingCommittee to Revise the 2001 Guidelines for the Management ofPatients With Atrial Fibrillation): developed in collaboration with theEuropean Heart Rhythm Association and the Heart Rhythm Society.Circulation. 2006;114:e257-354.
3. Gage BF, Waterman AD, Shannon W, et al. Validation of clinicalclassification schemes for predicting stroke: results from theNational Registry of Atrial Fibrillation. JAMA. 2001;285:2864-2870.
4. Van Gelder IC, Hagens VE, Bosker HA, et al. A comparison of ratecontrol and rhythm control in patients with recurrent persistentatrial fibrillation. N Engl J Med. 2002;347:1834-1840.
5. Wyse DG, Waldo AL, DiMarco JP, et al. A comparison of ratecontrol and rhythm control in patients with atrial fibrillation. N EnglJ Med. 2002;347:1825-1833.
In reply:Thank you for the opportunity to respond to the
observations and comments submitted by Drs. Goyal andGupta. The writers of this letter bring out a number ofimportant questions regarding our recently published study, “AProspective, Randomized Trial of an Emergency DepartmentObservation Unit for Acute Onset Atrial Fibrillation.”1 Forclarity, we will address the concerns numerically.
1. Drs. Goyal and Gupta point out that we suggest the study isrelevant to the importance of cost-effective management of afibrillation. However, the length of stay and costs were notspecified as primary or secondary outcomes.We are in agreement with the point of the authors. The primaryendpoint was conversion to sinus rhythm versus rate control at thecompletion of the emergency department (ED) observation unit
or hospital stay. Secondary endpoints were recurrence of atrialVolume , . : May