As the Zika virus continues to spread globally, new evidence has emerged about the virus's potentially detrimental effects on the heart.
The study included adult patients with no prior history of cardiovascular disease who were treated at the Institute of Tropical Medicine in Caracas, Venezuela, one of the epicenters of the Zika virus outbreak.
All but one patient developed a dangerous heart rhythm problem and two-thirds had evidence of heart failure.
The report has provided 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 timeframe also feel other symptoms such as fatigue, shortness of breath or their heart skipping beats, they should see their doctor.
This was seen with other mosquito-borne diseases known to affect the heart, including the dengue and Chikungunya viruses. However, the burden and severity of heart problems, including rapidly progressive heart failure and potentially life-threatening arrhythmias, among the patients infected with Zika virus was unexpected.
Nine patients who were seen in the clinic in Caracas within one week of having Zika-type symptoms and who subsequently reported common symptoms of heart problems, most commonly palpitations followed by shortness of breath and fatigue, were included in this small, prospective case report.
Only one patient had any previous cardiovascular problems ( well-controlled high blood pressure ), and lab tests confirmed that all had active Zika infection.
Patients were asked to fill out a form to record their symptoms and underwent an initial electrocardiogram which in eight cases was suggestive of a problem with the rate or rhythm of their heartbeat.
These findings prompted researchers to perform a full cardiovascular work up using an echocardiogram, Holter monitor and a cardiac magnetic resonance imaging study.
Of the nine patients, six were female with a mean age of 47 ± 17 years. They were followed for an average of six months, beginning in July 2016.
Dangerous arrhythmias were detected in eight of the nine patients: three cases of atrial fibrillation, two cases of non-sustained atrial tachycardia and two cases of ventricular arrhythmias.
Heart failure was present in six cases. Of these, five patients had heart failure with low ejection fraction and one had heart failure with preserved ejection fraction along with pre-eclampsia and a moderate to severe pericardial effusion.
None of the patients' cardiac issues have resolved, though symptoms are much improved due to guideline-directed treatment for heart failure or atrial fibrillation.
Cardiovascular symptoms tend to manifest later in the process. Data showed an average lag of 10 days from patients' initial complaints of Zika symptoms to reports of symptoms suggestive of heart problems.
Although cardiovascular manifestations are fairly rare against the total number of patients treated at the clinic, physicians believe many more cases will be diagnosed, not only in patients with clear symptoms, but also among those with less severe or no signs of myocarditis.
Myocarditis can affect the heart's muscle and electrical system.
For now, people who are traveling to areas with known Zika virus should consider talking with their doctor so they know what basic measures can be taken to prevent infection.
Symptoms of the Zika virus usually include mild fever, skin rash, conjunctivitis, muscle and joint pain, malaise or headache, which typically last for two to seven days, according to the World Health Organization ( WHO ).
The best way to prevent the Zika virus is by preventing mosquito bites.
Source: American College of Cardiology's 66th Annual Scientific Session, 2017