Authors: Martha Powell, Future Science Group
Zika virus may also cause detrimental effects on the cardiovascular system according to data being presented at the American College of Cardiology’s 66th Annual Scientific Session (March 17–19, Washington, USA). The study is the first to report Zika-related cardiac symptoms following infection, pointing to another potential complication of this emerging virus.
The small study included nine adult patients, eight of which had no prior history of cardiovascular disease, who were treated for Zika symptoms at the Institute of Tropical Medicine in Caracas, Venezuela. The participants all reported symptoms associated with cardiac problems, including palpitations, breathlessness and fatigue within a week of presenting with Zika symptoms.
The researchers confirmed Zika infection in all participants and asked individuals to record their symptoms. In addition, the patients underwent an electrocardiogram, which in eight of the nine cases was suggestive of an arrhythmia. Following these findings the team carried out a more comprehensive cardiac assessment including an echocardiogram, holter monitor and cardiac MRI.
Of the eight cases of arrhythmia the researchers elucidated three cases of atrial fibrillation, two cases of non-sustained atrial tachycardia and two cases of ventricular arrhythmia, which can be fatal. In addition to this, the researchers observed heart failure in six of the patients, five of which had a low ejection fraction.
The study’s lead author Karina Gonzalez Carta, from the Mayo Clinic (MN, USA), explained: “Our report provides clear evidence that there is a relationship between the Zika virus infection and cardiovascular complications. Based on these initial results, people need to be aware that if they travel to or live in a place with known Zika virus and develop a rash, fever or conjunctivitis, and within a short time frame also feel other symptoms such as fatigue, shortness of breath or their heart skipping beats, they should see their doctor.”
The team were not entirely surprised by their findings as related viruses, such as dengue and chikungunya, are known to cause cardiac complications. However, both the burden and severity of cardiac issues was unexpected. The authors stated that there was an average of 10 days between initial presentation with Zika symptoms and manifestation of cardiac problems.
Carta commented: “Since the majority of people with Zika virus infections present with mild or non-specific symptoms and symptoms of cardiovascular complications may not occur right away, we need to raise awareness about the possible association.”
This study points to a previously unreported potential risk of Zika infection; however, cardiac complications appeared to be fairly rare when compared with the total number of cases. Moreover, this study is limited due to a small sample size. The team are continuing to follow the participants from this cohort and also hope to screen more Zika patients for cardiovascular problems to understand this possible complication.
“It’s likely that many more people are affected, especially as many clinicians and people may not make the connection between symptoms,” Carta concluded. “We need larger, systematic studies to understand the actual risk of Zika-related cardiac problems and what makes one patient more prone to develop them.”