Review
Copyright ©The Author(s) 2017. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Methodol. Dec 26, 2017; 7(4): 117-128
Published online Dec 26, 2017. doi: 10.5662/wjm.v7.i4.117
Shortness of breath in clinical practice: A case for left atrial function and exercise stress testing for a comprehensive diastolic heart failure workup
Pupalan Iyngkaran, Nagesh S Anavekar, Christopher Neil, Liza Thomas, David L Hare
Pupalan Iyngkaran, Department of Medicine, Northern Territory Medical School, Flinders University, Charles Darwin University Campus, Casuarina, NT 0815, Australia
Nagesh S Anavekar, Department of Cardiology, Northern Hospital, Northern Health, University of Melbourne, Melbourne, VIC 3076, Australia
Christopher Neil, Cardiology Unit Western Health, Department of Medicine, Western Precinct, University of Melbourne, Melbourne, VIC 3076, Australia
Liza Thomas, South Western Sydney Clinical School, University of New South Wales, Sydney, NSW 214, Australia
Liza Thomas, Westmead Hospital, Westmead Clincal School, University of Sydney, NSW 2145, Australia
David L Hare, Cardiovascular Research, University of Melbourne, Melbourne, VIC 3076, Australia
David L Hare, Heart Failure Services, Austin Health, Melbourne, VIC 3084, Australia
Author contributions: Iyngkaran P wrote the paper; all authors read, agreed on arguments raised and provided feedback on paper.
Conflict-of-interest statement: All co-authors have secured independent and governmental research funding. None pose a conflict of interest for this review.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Pupalan Iyngkaran, FRACP, MBBS, MD, Department of Medicine, Northern Territory Medical School, Flinders University, Charles Darwin University Campus, Yellow Building 4 Cnr University Drive North and University Drive West, Casuarina NT 0815, Australia. pupalan.iyngkaran@flinders.edu.au
Telephone: +61-03-97487377 Fax: +61-03-97487388
Received: March 10, 2017
Peer-review started: March 17, 2017
First decision: May 23, 2017
Revised: June 29, 2017
Accepted: November 22, 2017
Article in press: November 22, 2017
Published online: December 26, 2017
Processing time: 290 Days and 11.8 Hours
Abstract

The symptom cluster of shortness of breath (SOB) contributes significantly to the outpatient workload of cardiology services. The workup of these patients includes blood chemistry and biomarkers, imaging and functional testing of the heart and lungs. A diagnosis of diastolic heart failure is inferred through the exclusion of systolic abnormalities, a normal pulmonary function test and normal hemoglobin, coupled with diastolic abnormalities on echocardiography. Differentiating confounders such as obesity or deconditioning in a patient with diastolic abnormalities is difficult. While the most recent guidelines provide more avenues for diagnosis, such as incorporating the left atrial size, little emphasis is given to understanding left atrial function, which contributes to at least 25% of diastolic left ventricular filling; additionally, exercise stress testing to elicit symptoms and test the dynamics of diastolic parameters, especially when access to the “gold standard” invasive tests is lacking, presents clinical translational gaps. It is thus important in diastolic heart failure work up to understand left atrial mechanics and the role of exercise testing to build a comprehensive argument for the diagnosis of diastolic heart failure in a patient presenting with SOB.

Keywords: Diastolic heart failure; Exercise stress test; Left atrium; Shortness of breath; Work-up

Core tip: Shortness of breath is a common clinical complaint. Etiologies such as systolic heart failure, obstructive airways disease or anemia have clear and reproducible physiological changes detectable through routine diagnostic tests. Diastolic heart failure (DHF) is often a diagnosis of exclusion. In the absence of directly demonstrating an elevation of left ventricular end diastolic pressures at rest or exercise, DHF is inferred by a combination of symptoms and resting echocardiography findings. We discuss the importance of a wider consideration, e.g., left atrium function and exercise stress testing, in DHF work-up.