Correspondence
Ventricular Ectopy after Exercise as a Predictor of Death
N Engl J Med 2003; 348:2357-2359June 5, 2003
- Article
To the Editor:
Frolkis et al. (Feb. 27 issue)1 found an association between frequent ventricular ectopy during recovery and decreased survival. However, we believe that two issues need to be addressed.
First, the authors do not indicate whether the subjects' electrocardiograms showed frequent ventricular ectopy at rest. The presence of frequent ventricular ectopy at rest may have been predictive of frequent ventricular ectopy during recovery and therefore may have been associated with decreased survival.
Second, a multivariable Cox regression model showed that frequent ventricular ectopy during recovery predicted an increased risk of death, with an adjusted hazard ratio of 1.6 (95 percent confidence interval, 1.2 to 2.2; P=0.005). However, the authors do not state which of the other variables listed in Table 1 of their article (e.g., prior myocardial infarction) were predictive of an increased risk of death. Therefore, a comparison of the adjusted hazard ratios associated with all the clinical variables listed would put the adjusted hazard ratio of 1.6 into better perspective. Although frequent ventricular ectopy may be predictive of an increased risk of death, analysis of other factors may add strength to this association.
1 ReferencesAtman P. Shah, M.D.
Stanley A. Rubin, M.D.
VA Greater Los Angeles, Los Angeles, CA 90073
ashah10@hotmail.com 1
Frolkis JP ,Pothier CE ,Blackstone EH ,Lauer MS . Frequent ventricular ectopy after exercise as a predictor of death. N Engl J Med 2003;348:781-790
Full Text | Web of Science | Medline
To the Editor:
In the study by Frolkis et al., how long were the patients observed after exercise? Were they seated or lying down? Was exercise abruptly stopped at the end of the protocol, or was a cool-down period routinely included after the exercise phase?
Sammy A. Gammenthaler, M.D.
Park Ridge Cardiology, Fletcher, NC 28732-5400To the Editor:
The prognostic importance of frequent ventricular ectopy during exercise testing was clearly shown by Frolkis and colleagues. In their study, frequent ventricular ectopy only during recovery was associated with an increased overall mortality, whereas the association did not reach statistical significance when frequent ventricular ectopy occurred only during exercise (P=0.09). This question was addressed in the Paris Prospective Study I.1 The two studies differed substantially with respect to the patient populations, the protocols for exercise testing, the study design, the time periods, and the end points. However, when we considered overall mortality in the Paris Prospective Study I, frequent ventricular ectopy during exercise, during recovery, or during both was a predictor of death (Table 1Table 1
Total Mortality 23 Years after Exercise Testing in 6101 Asymptomatic Working Men (42 to 53 Years of Age) Recruited between 1967 and 1972 in the Paris Prospective Study I.). These very similar results obtained with such different methods are striking. In our opinion, frequent ventricular ectopy should be considered as a new prognostic criterion in addition to ischemia.2 2 ReferencesXavier P. Jouven, M.D., Ph.D.
Jean-Philippe Empana, M.D.
INSERM Avenir Hôpital Européen Georges Pompidou, 75015 Paris, France
xavier.jouven@egp. ap-hop-paris. fr Pierre Ducimetière, Ph.D.
INSERM Avenir Unité 258, 94807 Villejuif, France1
Jouven X ,Zureik M ,Desnos M ,Courbon D ,Ducimetiere P . Long-term outcome in asymptomatic men with exercise-induced premature ventricular depolarizations. N Engl J Med 2000;343:826-833
Full Text | Web of Science | Medline2
Jouven X ,Ducimetiere P . Exercise testing: do frequent premature ventricular depolarizations represent a new criterion of positivity? Eur Heart J 2001;22:1759-1761
CrossRef | Web of Science | Medline
Author/Editor Response
We thank Dr. Jouven and colleagues for sharing their data from the Paris Prospective Study I. We completely agree that frequent ventricular ectopy associated with exercise testing should be considered a new prognostic criterion during routine evaluation.
Drs. Shah and Rubin ask about frequent ventricular ectopy at rest. As we mentioned in the Methods section of our article, patients with frequent ventricular ectopy at rest were excluded from our study cohort. We also excluded patients who were referred for exercise testing as part of an arrhythmia evaluation. Drs. Shah and Rubin also ask for information about other variables that were predictive of death and their adjusted hazard ratios. These data are shown in Table 1Table 1
Independent Predictors of Death from All Causes among 29,244 Patients Referred for Symptom-Limited Exercise Testing.. The adjusted hazard ratio associated with frequent ventricular ectopy during recovery was similar in magnitude to the adjusted hazard ratios associated with male sex, tobacco use, chronic lung disease, diabetes, left bundle-branch block, a fair level of physical fitness, and abnormal heart-rate recovery.Dr. Gammenthaler asks about the recovery protocols that were used. The majority of the 29,244 patients (25,237 [86 percent]) underwent a two-minute cool-down period in which they walked 1.5 miles per hour at a 2.5 percent grade, followed by a three-minute period of sitting. The 4007 patients undergoing stress echocardiography (14 percent) assumed a left lateral decubitus position immediately after exercise. All the patients were monitored for five minutes; in 92 percent of the patients who had ventricular ectopy during recovery, it first appeared during the first three minutes.
Dr. Gammenthaler's question raises the possibility that the type of recovery protocol might affect the frequency or prognostic value of frequent ventricular ectopy during recovery. Among the 25,237 patients who underwent a cool-down period, frequent ventricular ectopy during recovery was noted in 931 (4 percent) and was associated with an increased risk of death (12 percent vs. 5 percent; age-adjusted hazard ratio, 1.7; 95 percent confidence interval, 1.4 to 2.1; P<0.001). Of the 4007 patients who immediately assumed a supine position, frequent ventricular ectopy was noted in 149 (4 percent) and was similarly associated with an increased risk of death (10 percent vs. 6 percent; age-adjusted hazard ratio, 1.6; 95 percent confidence interval, 1.0 to 2.7; P=0.06). There was no interaction between frequent ventricular ectopy during recovery and the type of recovery protocol used for the prediction of death (P for interaction, 0.97).
Michael S. Lauer, M.D.
Cleveland Clinic Foundation, Cleveland, OH 44195
lauerm@ccf.org Joseph P. Frolkis, M.D., Ph.D.
University Hospitals of Cleveland, Cleveland, OH 44106Eugene H. Blackstone, M.D.
Cleveland Clinic Foundation, Cleveland, OH 44195- Citing Articles (4)
Citing Articles
1
Philip Greenland, Joseph S. Alpert, George A. Beller, Emelia J. Benjamin, Matthew J. Budoff, Zahi A. Fayad, Elyse Foster, Mark A. Hlatky, John McB. Hodgson, Frederick G. Kushner, Michael S. Lauer, Leslee J. Shaw, Sidney C. Smith, Allen J. Taylor, William S. Weintraub, Nanette K. Wenger. (2010) 2010 ACCF/AHA Guideline for Assessment of Cardiovascular Risk in Asymptomatic Adults. Journal of the American College of Cardiology 56:25, e50-e103
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John S. Ho, Shannon J. FitzGerald, Carolyn E. Barlow, John J. Cannaday, Harold W. Kohl, William L. Haskell, Kenneth H. Cooper. (2010) Risk of mortality increases with increasing number of abnormal non-ST parameters recorded during exercise testing. European Journal of Cardiovascular Prevention & Rehabilitation 17:4, 462-468
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R. Berent, J. Auer, S.P. Duvillard, H. Sinzinger, P. Schmid. (2010) Komplikationen bei der Ergometrie. Herz 35:4, 267-272
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Michael S. Lauer. (2004) Chronotropic incompetence. Journal of the American College of Cardiology 44:2, 431-432
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