Elsevier

Resuscitation

Volume 126, May 2018, Pages 1-6
Resuscitation

Clinical paper
Changes in left ventricular systolic and diastolic function on serial echocardiography after out-of-hospital cardiac arrest

https://doi.org/10.1016/j.resuscitation.2018.01.050Get rights and content

Abstract

Aim

Reversible myocardial dysfunction is common after out-of-hospital cardiac arrest (OHCA). The aim of this study was to determine if changes on serial transthoracic echocardiography (TTE) can predict long-term mortality in OHCA subjects.

Methods

This is a single-center historical cohort study of OHCA subjects undergoing targeted temperature management who received >1 TTE during hospitalization. Two-dimensional and Doppler parameters of systolic and diastolic function were compared between paired TTE. Univariate analysis was used to determine associations between TTE parameters and all-cause mortality.

Results

Fifty-nine patients were included; mean age was 59.4 ± 11.2 years (75% male). Initial rhythm was shockable in 90%. Initial TTE was done a median of 10.4 h after admission and repeat TTE was done 5.7 ± 4.1 days later. Between TTE studies, there were significant increases in left ventricular ejection fraction (LVEF, from 32% to 43%), cardiac output, stroke volume, and other Doppler-derived hemodynamic parameters, while systemic vascular resistance decreased (all p < 0.001). Systolic function and hemodynamic parameters on initial TTE were not associated with follow-up mortality. Patients who died during follow-up (n = 16, 27%) had smaller increases in LVEF and cardiac output-derived hemodynamic parameters than long-term survivors (p < 0.05).

Conclusions

Significant changes in systolic function and hemodynamic parameters occur on serial Doppler TTE after OHCA, consistent with reversible post-arrest myocardial dysfunction. The magnitude of those changes is greater in long-term survivors, emphasizing that the degree of recovery from post-arrest myocardial dysfunction may be more important than its initial severity.

Introduction

Out-of-hospital cardiac arrest (OHCA) is a leading cause of mortality and morbidity among adults, leading to over 300,000 deaths in the United States annually [1]. Individuals resuscitated from OHCA frequently develop a characteristic post-cardiac arrest syndrome, including cardiovascular failure with circulatory shock and myocardial dysfunction [[2], [3]]. Post-arrest myocardial dysfunction (PAMD) occurs in up to 70% of subjects resuscitated from OHCA [3]. PAMD after OHCA can be reversible, with decreases in cardiac output and LV systolic function early after OHCA that often improve spontaneously over time [[3], [4], [5], [6]].

Prior studies have found that subjects who do not survive hospitalization after OHCA have more severe LV systolic dysfunction without subsequent recovery [[4], [5]]. Despite this, the presence of LV systolic dysfunction itself has not been consistently associated with adverse outcomes [[7], [8]]. On the contrary, at least one study has suggested that LV diastolic dysfunction rather than LV systolic dysfunction is associated with increased mortality after OHCA [8]. No prior studies have systematically examined the relationship between temporal echocardiographic changes and outcomes after OHCA. The goal of the current investigation was to determine if changes in LV systolic and diastolic function on serial Doppler echocardiography are associated with long-term mortality in subjects with OHCA.

Section snippets

Methods

This study was reviewed and approved by the Institutional Review Board of the Mayo Clinic (Rochester, MN) under a waiver of informed consent as posing minimal risk to subjects.

Results

During the study period, 190 adult subjects were admitted for TTM after OHCA, and 173 (91%) underwent inpatient TTE. The 59 subjects who had more than one TTE during hospitalization comprised the final study population (31% of total OHCA subjects; Supplementary Fig. 1). Baseline characteristics of subjects that underwent one or >1 TTE during admission are shown in Table 1. Subjects undergoing multiple TTEs were similar to those with a single TTE, except that they were younger (age 59 vs. 63

Discussion

This is the first published study describing changes in Doppler TTE hemodynamic parameters in OHCA subjects. In this study of 59 subjects undergoing TTM after OHCA who had serial TTE during hospitalization, we were able to demonstrate changes in cardiac systolic and diastolic function using Doppler echocardiographic parameters not previously described in this critically-ill population. TTE markers of LV systolic function and cardiac performance all increased significantly between TTEs. Markers

Conclusions

Using serial Doppler TTE in a cohort of subjects undergoing TTM after resuscitation from OHCA, this study characterized the evolving hemodynamic abnormalities of PAMD. Initial systolic function and Doppler-derived hemodynamic parameters did not predict mortality. Survivors had greater recovery of LV systolic dysfunction on follow-up TTE, and the increases in CO and CI between TTE were strongly associated with long-term mortality. This study demonstrates the novel finding that the mitral E/e’

Conflicts of interest

The authors have no conflicts of interest to report related to this work.

Relationships with Industry and Other Entities

None.

Funding

None.

Acknowledgement

The authors would like to thank the dedicated nurses and physicians who care for our OHCA patients every day.

References (14)

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A Spanish translated version of the abstract of this article appears as Appendixi n the final online version at http://dx.doi.10.1016/j.resuscitation.2018.01.050.

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