0
Correspondence |

Prediction of Mortality in Pulmonary Embolism Based on Left Atrial Volume Measurements: Do Indexed Values Matter? FREE TO VIEW

Ajay Yadlapati, MD; Stuart Rich, MD; Jeremy Collins, MD; D. Mark Courtney, MD; Daniel R. Schimmel, MD
Author and Funding Information

FINANCIAL/NONFINANCIAL DISCLOSURES: None declared.

aDivision of Cardiology, Northwestern Memorial Hospital, Northwestern University Feinberg School of Medicine, Chicago, IL

bDepartment of Radiology, Northwestern Memorial Hospital, Northwestern University Feinberg School of Medicine, Chicago, IL

cDepartment of Emergency Medicine, Northwestern Memorial Hospital, Northwestern University Feinberg School of Medicine, Chicago, IL

CORRESPONDENCE TO: Ajay Yadlapati, MD, Division of Cardiology, Northwestern University, Feinberg School of Medicine, 676 N St. Clair St, Ste 600, Chicago, IL 60611


Copyright 2016, American College of Chest Physicians. All Rights Reserved.


Chest. 2016;150(1):253-254. doi:10.1016/j.chest.2016.04.027
Text Size: A A A
Published online

We read the paper by Aviram et al published in CHEST (March 2016) with great interest and congratulate the authors on their excellent work. Using CT pulmonary angiography (CTPA), the study demonstrated an association of decreased left atrial (LA) volumes and mortality in patients with acute pulmonary embolism (PE), in which it is theorized that a decrease in right ventricular stroke volume leads to underfilling of the left atrium. These findings are corroborated by previous studies using echocardiography and advocate the need for further studies using CTPA to risk stratify high-risk patients with PE.

The current analysis suggests that patients with a smaller LA volume, by nongated CTPA, have a higher risk of mortality after PE. Given the known heterogeneity of LA volumes according to body surface area (BSA), it would be helpful to index LA volumes to BSA. Studies have demonstrated that LA size was larger with increasing body size and male sex, potentially explaining up to 29% of LA size variability. Additionally, race should be taken into account because of the significantly greater dimensions among whites, as well as evident racial disparities with PE mortality. To partially account for patient BSA, right atrial to LA ratio was used by Chow et al to predict long-term mortality; however, this association was not as definitive. The CTPA images are nongated and represent data from a range of cardiac phases, with reduced filling time at higher heart rates. This may partly account for why the right atrial to LA volume ratio association is not as strong by CTPA. The increasing availability of advanced CT scanner systems will enable excellent-quality gated PE examinations, making metrics derived from chamber volumes more reliable.

Despite the population-associated risk of low LA volume with increased mortality, the interquartile ranges overlap significantly, making LA volume difficult to apply to a particular patient with acute PE. Finally, to evaluate the discriminatory capacity of new tests in the setting of their widespread application, a comparison with biomarker elevation is necessary to show incremental discriminatory power.

The assessment of risk in acute PE is challenging. The findings presented by Aviram et al provide a framework for further risk stratification at the time of diagnosis by noninvasive methods, providing clinicians additional objective data. Further studies using gated imaging and patient-specific LA metrics in comparison with currently used risk tools will help validate this novel metric for risk assessment in patients with PE.

References

Aviram G. .Soikher E. .Bendet A. .et al Prediction of mortality in pulmonary embolism based on left atrial volume measured on CT pulmonary angiography. Chest. 2016;149:667-675 [PubMed]journal. [CrossRef] [PubMed]
 
Pritchett A.M. .Jacobsen S.J. .Mahoney D.W. .Rodeheffer R.J. .Bailey K.R. .Redfield M.M. . Left atrial volume as an index of left atrial size: a population-based study. J Am Coll Cardiol. 2003;41:1036-1043 [PubMed]journal. [CrossRef] [PubMed]
 
Dewland T.A. .Bibbins-Domingo K. .Lin F. .et al Racial differences in left atrial size: results from the Coronary Artery Risk Development in Young Adults (CARDIA) study. PLoS One. 2016;11:e0151559- [PubMed]journal. [CrossRef] [PubMed]
 
Horlander K.T. .Mannino D.M. .Leeper K.V. . Pulmonary embolism mortality in the United States, 1979-1998: an analysis using multiple-cause mortality data. Arch Intern Med. 2003;163:1711-1717 [PubMed]journal. [CrossRef] [PubMed]
 
Chow V. .Ng A.C. .Chung T. .Thomas L. .Kritharides L. . Right atrial to left atrial area ratio on early echocardiography predicts long-term survival after acute pulmonary embolism. Cardiovasc Ultrasound. 2013;11:17- [PubMed]journal. [CrossRef] [PubMed]
 

Figures

Tables

References

Aviram G. .Soikher E. .Bendet A. .et al Prediction of mortality in pulmonary embolism based on left atrial volume measured on CT pulmonary angiography. Chest. 2016;149:667-675 [PubMed]journal. [CrossRef] [PubMed]
 
Pritchett A.M. .Jacobsen S.J. .Mahoney D.W. .Rodeheffer R.J. .Bailey K.R. .Redfield M.M. . Left atrial volume as an index of left atrial size: a population-based study. J Am Coll Cardiol. 2003;41:1036-1043 [PubMed]journal. [CrossRef] [PubMed]
 
Dewland T.A. .Bibbins-Domingo K. .Lin F. .et al Racial differences in left atrial size: results from the Coronary Artery Risk Development in Young Adults (CARDIA) study. PLoS One. 2016;11:e0151559- [PubMed]journal. [CrossRef] [PubMed]
 
Horlander K.T. .Mannino D.M. .Leeper K.V. . Pulmonary embolism mortality in the United States, 1979-1998: an analysis using multiple-cause mortality data. Arch Intern Med. 2003;163:1711-1717 [PubMed]journal. [CrossRef] [PubMed]
 
Chow V. .Ng A.C. .Chung T. .Thomas L. .Kritharides L. . Right atrial to left atrial area ratio on early echocardiography predicts long-term survival after acute pulmonary embolism. Cardiovasc Ultrasound. 2013;11:17- [PubMed]journal. [CrossRef] [PubMed]
 
NOTE:
Citing articles are presented as examples only. In non-demo SCM6 implementation, integration with CrossRef’s "Cited By" API will populate this tab (http://www.crossref.org/citedby.html).

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging & repositioning the boxes below.

Find Similar Articles
  • CHEST Journal
    Print ISSN: 0012-3692
    Online ISSN: 1931-3543