Dengue-Associated Myocarditis and Conduction Abnormalities: Underrecognized Cardiac Manifestations of Expanded Dengue Syndrome

The dengue virus, spread by female aedes mosquito is a very common infection we see, the 4 different kinds of strains that cause this dengue fever are often endemic to certain regions in Asia and Latin America but the common symptoms seen with this infection are no longer our only threat, the classical dengue fever, petechiae, purpura or the muscle pain and other symptoms seen with the infection are still around but now various cases around the world report extra and unusual organ involvement seen with dengue infection although there are multiple systemic effects newly seen, one such particular organ involvement that is quite severe and sometimes fatal is the heart and the complication we will be most focused on would be dengue associated myocarditis.

Clinicians around the world do not screen the dengue patients for cardiac abnormalities and in some way it actually makes sense but the increase in cardiac manifestations of dengue patients is both concerning and of great importance. The cardiac manifestations of this infection range from transient arrhythmias

cardiogenic shock, edema to very severe conduction problems that require permanent pacing in the heart .The complications are so insidious and tough to diagnose that the reported fatal case of dengue associated myocarditis was not diagnosed until autopsy. This article aims to increase awareness of this new development of non-classical organ involvement, diagnostic methods that detect the new symptoms.

The involvement of cardiac signs with dengue is less seen but not completely absent, multiple studies regarding this have definitive conclusions , this dengue associated with myocarditis increases the risk of severe disease, another PUB-MED research having 339 dengue patients with cardiac complications, the symptoms ranged from tachyarrhythmia which were self limiting , bradycardia to severe myocardial damage. Different studies on the mortality and disease severeness were done to conclude that the mortality was high in adults ( older patients) and many more severe manifestations were seen among children and female adults and many severe causes such as dengue hemorrhagic fever and third degree A-V block along with subclinical myocarditis were observed.

The prevalence of myocarditis is seen more in Asia compared to Latin America (15.2% vs 3.5%), this highlights the need of the dengue endemic clinicians to screen patients with previous heart complications for dengue associated myocarditis, the presentations of this patient ranged from transient arrythmias to fulminant myocarditis , cardiogenic shock , pulmonary edema and irreversible conduction abnormalities that leave the need of permanent heart pacing, Due to this the clinicians should be very active in diagnosing such cases, as there were few but noticeable amount of deaths.. This need of early diagnosis is in dengue endemic regions, particularly in patients of arrythmias,hypotension,elevated cardiac biomarkers or sudden deterioration without reason.

The article is of importance as it aims to highlight the early recognition of myocardial involvement as well as other systemic involvement and also to highlight the association underrecognized cardiac manifestation of dengue, The solution could be the use of early ECG, echocardiographic and troponin testing for diagnosis and intervention.