Hemodynamic profiles of patients with dengue hemorrhagic fever during toxic stage: an echocardiographic study

Abstract

Objective

To study left ventricular performance and hemodynamic abnormalities during different stages of dengue hemorrhagic fever (DHF).

Design and setting

Observational study in a tertiary medical school hospital.

Patients

Twenty-four patients with serologically confirmed diagnosis of dengue virus infection and DHF according to the WHO criteria.

Methods

Echocardiography was performed during toxic, convalescent stages and at least 2 weeks after discharge (recovery). Left ventricular ejection fraction, rate-corrected velocity of circumferential fiber shortening adjusted for end-systolic meridional wall stress (VCFC/ESS) Z score, end-diastolic volume Z score, cardiac index, heart rate, mean arterial pressure, and total systemic vascular resistance (SVR) were compared between different stages of DHF.

Results

Ejection fraction and VCFC/ESS were significantly lower during the toxic stage than after recovery. End-diastolic volume was low during toxic stage and returned to normal during convalescence and recovery. Cardiac index was low during the toxic stage due to decreased preload (low end-diastolic volume) and depressed left ventricular ejection fraction. Cardiac index remained subnormal during convalescence due to sinus bradycardia. Wide variation in heart rate during toxic stage resulted in a small, nonsignificant increase compared to recovery. With treatment, heightened SVR resulted in relatively normal mean arterial pressure throughout the course of the illness.

Conclusions

The mechanism of decreased cardiac output during toxic stage of DHF is complex. Decreased preload is accompanied by decreased left ventricular performance, and possibly a subnormal heart rate response in some patients.