Prospective Study
Copyright ©The Author(s) 2018. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Crit Care Med. Feb 4, 2018; 7(1): 16-23
Published online Feb 4, 2018. doi: 10.5492/wjccm.v7.i1.16
Spectrum of cardiac manifestations and its relationship to outcomes in patients admitted with scrub typhus infection
Gunasekaran Karthik, Thomas Isaiah Sudarsan, John Victor Peter, Thambu Sudarsanam, George M Varghese, Paul Kundavaram, Sowmya Sathyendra, Ramya Iyyadurai, Kishore Pichamuthu
Gunasekaran Karthik, Thambu Sudarsanam, Paul Kundavaram, Sowmya Sathyendra, Ramya Iyyadurai, Department of Medicine, Christian Medical College, Vellore 632004, India
Thomas Isaiah Sudarsan, John Victor Peter, Kishore Pichamuthu, Medical Intensive Care Unit, Christian Medical College, Vellore 632004, India
George M Varghese, Department of Infectious Diseases, Christian Medical College, Vellore 632004, India
Author contributions: Sudarsan TI acted as guarantor and corresponded with the journal for this paper; Karthik G, Peter JV, Sudarsanam T, Varghese GM, Kundavaram P, Sathyendra S, Iyyadurai R and Pichamuthu K contributed to acquisition of the data and revision of this manuscript.
Institutional review board statement: This study was approved by the local Institutional Review Board (No. 8104).
Informed consent statement: All study participants, or their legal guardian, provided informed written consent prior to study enrollment.
Conflict-of-interest statement: There are no financial implications or conflict of interest to declare for any of the authors.
Data sharing statement: No additional data is available.
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: Dr. Thomas Isaiah Sudarsan, MD, IDCC, Assistant Professor, Medical Intensive Care Unit, Christian Medical College, Ida Scudder Road, Vellore 632004, India. thomas5777@cmcvellore.ac.in
Telephone: +91-98-4017089
Received: October 5, 2017
Peer-review started: October 29, 2017
First decision: November 30, 2017
Revised: December 8, 2017
Accepted: December 28, 2017
Article in press: December 28, 2017
Published online: February 4, 2018
Processing time: 96 Days and 15.3 Hours
Abstract
AIM

To study the spectrum of cardiac manifestations in scrub typhus infection and assess its relationship to outcomes.

METHODS

Demographic data, electrocardiographic (ECG) changes, left ventricular (LV) systolic and diastolic function, myocardial injury (defined as troponin T > 14 pg/mL), and pericardial effusion were documented. Myocarditis was diagnosed when myocardial injury was associated with global LV systolic dysfunction. The relationship between myocarditis and outcomes was assessed using logistic regression analysis and expressed as odds ratio (OR) with 95%CI.

RESULTS

The cohort (n = 81; 35 males) aged 49.4 ± 16.1 years (mean, SD) presented 8.1 ± 3.1 d after symptom onset. The APACHE-II score was 15.7 ± 7.0. Forty-eight (59%) patients were ventilated, and 46 (56%) required vasoactive agents. Mortality was 9.9%. ECG changes were non-specific; sinus tachycardia was the most common finding. Myocardial injury was evident in 61.7% of patients and LV systolic dysfunction in 30.9%. A diagnosis of myocarditis was made in 12.3%. In addition, seven patients with regional wall motion abnormalities had LV systolic dysfunction and elevated cardiac enzymes. Mild diastolic dysfunction was observed in 18 (22%) patients. Mild to moderate pericardial effusion was seen in 51%. On multivariate logistic regression analysis, patients with myocarditis tended to be older (OR = 1.04, 95%CI: 0.99-1.09), had shorter symptom duration (OR = 0.69, 95%CI: 0.49-0.98), and tended to stay longer in hospital (OR = 1.17, 95%CI: 0.98-1.40). Myocarditis was not associated with increased mortality.

CONCLUSION

In scrub typhus infection, cardiac manifestations are frequent and associated with increased morbidity but not mortality.

Keywords: Scrub typhus; Myocarditis; Outcome

Core tip: This study characterizes the cardiac manifestations in scrub typhus using a combination of clinical parameters, biomarkers, and echocardiography. In this prospective cohort study, 81 patients admitted with scrub typhus infection were enrolled. A wide range of cardiac manifestations were observed from non-specific electrocardiographic changes to pericarditis, myocarditis, and circulatory shock. Myocarditis occurred in 12.3% of the patients. Patients with myocarditis had significantly shorter symptom duration (OR = 0.69, 95%CI: 0.49-0.98) and tended to stay longer in hospital (OR = 1.17, 95%CI 0.98-1.40). An effect on mortality was not demonstrable.