QUARTERLY FOCUS ISSUE: HEART FAILURE: CLINICAL RESEARCH
Profiles of Serial Changes in Cardiac Troponin T Concentrations and Outcome in Ambulatory Patients With Chronic Heart Failure
Wayne L. Miller, MD, PhD*,*,
Karen A. Hartman, BSN*,
Mary F. Burritt, PhD ,
Diane E. Grill, MSc and
Allan S. Jaffe, MD*,
* Division of Cardiovascular Diseases, Department of Medicine, Mayo Clinic, Rochester, Minnesota
Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota
Division of Biostatistics, Mayo Clinic, Rochester, Minnesota
Manuscript received May 19, 2009;
revised manuscript received June 23, 2009,
accepted July 30, 2009.
* Reprint requests and correspondence: Dr. Wayne L. Miller, Mayo Clinic, 200 First Street SW, Rochester, Minnesota 55905 (Email: miller.wayne{at}mayo.edu).
Objectives: The purpose of this study was to determine whether different profiles of cardiac troponin T (cTnT) values assessed over time would yield incremental prognostic information on clinically stable outpatients with heart failure (HF).
Background: cTnT levels were used to estimate prognosis in HF; however, most studies evaluated hospitalized patients using single measurements.
Methods: A cohort of 172 New York Heart Association functional class III to IV outpatients was prospectively studied with serial cTnT measurements collected every 3 months over a 2-year period. The primary end point was death or cardiac transplantation, and secondary end points included HF hospitalization.
Results: Of the 172 patients, 22 (13%) died or underwent transplantation during the first year. Therefore, 150 patients were included in the second-year analysis of 3 pre-determined groups: 1) no serial cTnT elevations (defined as <0.01 ng/ml); 2) 1 or more, but not all cTnT values elevated  0.01 ng/ml; and 3) all cTnT values elevated during the first year. During the second year, 30 events occurred: 53 patients had persistently normal cTnT levels (<0.01 ng/ml) with 6 primary events (11%); 57 patients had 1 or more but not all cTnT levels elevated with 11 events (19%); 40 patients demonstrated persistently elevated cTnT levels with 13 (33%) primary events (odds ratio: 3.77; 95% confidence interval: 1.28 to 11.07, p = 0.02).
Conclusions: Elevations in cTnT, even using a low threshold of 0.01 ng/ml, detected during routine clinical follow-up of ambulatory patients with HF, are highly associated with an increased risk of events, particularly with frequent or persistent cTnT elevations of 0.01 ng/ml. Therefore, the ability to monitor clinical change through serial cTnT measurements may add to risk assessment in the ambulatory HF population.
Key Words: chronic heart failure • troponin T • outcomes • outpatients
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Abbreviations and Acronyms
| | BNP = B-type natriuretic peptide | | CI = confidence interval | | cTnT = cardiac troponin T | | HF = heart failure | | NYHA = New York Heart Association | | OR = odds ratio |
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Inside This Issue
J. Am. Coll. Cardiol. 2009 54: A26.
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