Clinical Studies
Echocardiography in patients with suspected endocarditis: a cost-effectiveness analysis

https://doi.org/10.1016/S0002-9343(99)00216-8Get rights and content

Abstract

PURPOSE: We sought to determine the appropriate use of echocardiography for patients with suspected endocarditis.

PATIENTS AND METHODS: We constructed a decision tree and Markov model using published data to simulate the outcomes and costs of care for patients with suspected endocarditis.

RESULTS: Transesophageal imaging was optimal for patients who had a prior probability of endocarditis that is observed commonly in clinical practice (4% to 60%). In our base-case analysis (a 45-year-old man with a prior probability of endocarditis of 20%), use of transesophageal imaging improved quality-adjusted life expectancy (QALYs) by 9 days and reduced costs by $18 per person compared with the use of transthoracic echocardiography. Sequential test strategies that reserved the use of transesophageal echocardiography for patients who had an inadequate transthoracic study provided similar QALYs compared with the use of transesophageal echocardiography alone, but cost $230 to $250 more. For patients with prior probabilities of endocarditis greater than 60%, the optimal strategy is to treat for endocarditis without reliance on echocardiography for diagnosis. Patients with a prior probability of less than 2% should receive treatment for bacteremia without imaging. Transthoracic imaging was optimal for only a narrow range of prior probabilities (2% or 3%) of endocarditis.

CONCLUSION: The appropriate use of echocardiography depends on the prior probability of endocarditis. For patients whose prior probability of endocarditis is 4% to 60%, initial use of transesophageal echocardiography provides the greatest quality-adjusted survival at a cost that is within the range for commonly accepted health interventions.

Section snippets

Decision model

We developed a decision model using EXCEL (Version 5.0, Microsoft Corporation, Redmond, Washington) and DATA (Version 3.0, TreeAge Software, Boston, Massachusetts) software. The model compares six strategies for the diagnosis of endocarditis Figure 1, Figure 2. It consists of a decision tree that represents the immediate consequences for patients with suspected endocarditis, and a four-state Markov model 16, 17 to evaluate long-term survival. In the first strategy (bacteremia treatment), no

Results

For our base-case analysis of a 45-year-old man with a 20% prior probability of endocarditis, use of transesophageal echocardiography, either alone or after transthoracic echocardiography, provided the greatest quality-adjusted life expectancy (Table 4). Both of these strategies provided 9 additional quality-adjusted days of life compared with using a transthoracic study alone to determine treatment. Compared with the use of transesophageal echocardiography alone, treatment of all patients for

Discussion

We evaluated the cost-effectiveness of several diagnostic strategies for a patient with suspected endocarditis. Our base-case analysis (a 45-year-old patient with unexplained bacteremia) indicates that the use of transesophageal echocardiography alone provides the greatest QALYs at the lowest cost when compared with the use of a transthoracic study alone, use of a transthoracic study first followed by a transesophageal study if the initial study is negative, or treatment for endocarditis

References (58)

  • A.B Weisse et al.

    The febrile parenteral drug usera prospective study in 121 patients

    Am J Med

    (1993)
  • C.F Von Reyn et al.

    Case definitions for infective endocarditis

    Am J Med

    (1994)
  • S.B Calderwood et al.

    Prosthetic valve endocarditis. Analysis of factors affecting outcome of therapy

    J Thorac Cardiovasc Surg

    (1986)
  • K.J Yvorchuk et al.

    Application of transthoracic and transesophageal echocardiography in the diagnosis and management of infective endocarditis

    J Am Soc Echocardiogr

    (1994)
  • H.F Chambers

    Transesophageal echocardiography in endocarditis

    Chest

    (1994)
  • W.N Irani et al.

    A negative transthoracic echocardiogram obviates the need for transesophageal echocardiography in patients with suspected native valve active infective endocarditis

    Am J Cardiol

    (1996)
  • M.F Stoddard et al.

    The safety of transesophageal echocardiography in the elderly

    Am Heart J

    (1993)
  • M Sande et al.

    Endocarditis

    (1984)
  • L Weinstein et al.

    Infective Endocarditis

    (1996)
  • C.F Von Reyn et al.

    Infective endocarditisan analysis based on strict case definitions

    Ann Intern Med

    (1981)
  • H.C Dittrich et al.

    Is transesophageal echocardiography necessary in all patients with suspected endocarditis?

    Cardiol Rev

    (1993)
  • D.T Durack

    Prevention of infective endocarditis

    NEJM

    (1995)
  • N Schiller

    Clinical decision making in patients with endocarditisthe role of echocardiography

  • W.G Daniel et al.

    Safety of transesophageal echocardiography. A multicenter survey of 10,419 examinations

    Circulation

    (1991)
  • G Khandheria et al.

    Infective endocarditis

  • J.R Lindner et al.

    Diagnostic value of echocardiography in suspected endocarditis. An evaluation based on the pretest probability of disease

    Circulation

    (1996)
  • J.R Beck et al.

    The Markov process in medical prognosis

    Med Decis Making

    (1983)
  • F.A Sonnenberg et al.

    Markov models in medical decision makinga practical guide

    Med Decis Making

    (1993)
  • Lipscomb J, Weinstein MC, Torrance GW. Time preference. In: Gold MR, Siegel JE, Russell LB, et al, eds....
  • Cited by (104)

    • Endocarditis and Intravascular Infections

      2014, Mandell, Douglas, and Bennett's Principles and Practice of Infectious Diseases
    • Neurologic Manifestations of Infective Endocarditis

      2014, Aminoff's Neurology and General Medicine: Fifth Edition
    • Endocarditis

      2013, Perioperative Transesophageal Echocardiography: A companion to Kaplan's Cardiac Anesthesia
    View all citing articles on Scopus

    Drs. Owens and Heidenreich were supported by career development awards from the Veterans Affairs Health Services Research and Development Service.

    View full text