The involvement of the pulmonic valve and the pulmonary artery in infective endocarditis (IE) is rare. Unrepaired congenital heart disease (CHD), including patent ductus arteriosus (PDA), is a risk factor for IE. A previous IE is likewise a significant risk factor that predisposes to IE recurrence. Discriminating between IE recurrence and a persistence of a vegetation from a previously treated IE can be difficult. This paper is aimed at describing a case of pulmonic valve and pulmonary artery vegetations in a pregnant patient with an unrepaired PDA and a distant history of IE treatment. This is the first documented case of pulmonic valve and pulmonary artery vegetation in a patient with a PDA in our institution.
This is the case of 19-year-old primigravid with an unrepaired PDA who was incidentally found to have vegetations on the pulmonary artery and pulmonic valve on routine prenatal transthoracic echocardiogram (TTE).
She had an unremarkable childhood until 10 years old when she was diagnosed with moderate patent ductus arteriosus, presenting as exertional dyspnea. She was lost to follow-up until 2 years later, at 12 years old, when she was admitted at the emergency room for edema, exertional dyspnea, and orthopnea. On physical examination, she was in respiratory distress, tachypneic with alar flaring, and had bilateral crackles. She was initially treated for community-acquired pneumonia and pulmonary tuberculosis, with initial blood cultures yielding
She returned to our institution for prenatal care. She discontinued taking furosemide, enalapril, and digoxin at the start of pregnancy. Given her history of a congenital heart disease, a TTE was ordered as part of the prenatal work-up. The TTE was done on her 29th week AOG, and it revealed a PDA with a computed Qp : Qs of 1.18 (see Figure
In the short axis view at the level of the aortic valve, there is a retrograde mosaic jet entering the distal pulmonary artery from the posterolateral direction, indicative of patent ductus arteriosus, with the following measurements: PSAX 9 mm, 10 mm (with color); suprasternal 8.1 mm, 1 mm (with color). Continuous flow across the defect is demonstrated on spectral Doppler. Computed Qp : Qs is 1.18.
In the short axis view at the level of the aortic valve, there are mobile echogenic vegetations attached to the pulmonary artery (a) measuring
Despite the absence of fever and signs of worsening heart failure, she was preemptively admitted and treated empirically for IE with intravenous ceftriaxone. During this period, she did not have fever nor signs of decompensation. Serial blood cultures were negative. On repeat TTE after 2 weeks, there was only a slight decrease in the size of the vegetation and it was treated as a persistent vegetation from her previous bout of IE at 12 years old. She was advised surgery, for closure of the PDA and harvest of vegetations, after delivery, but the patient did not consent. The rest of her perinatal course was uneventful.
According to the European Society of Cardiology (ESC), at present, 0.2 to 4% of all pregnancies in western industrialized countries are complicated by cardiovascular diseases. Maternal heart disease, in general, is now said to be the major cause of maternal death during pregnancy. Because of improved treatment of CHD during childhood, more of these patients reach child-bearing age. In western countries, CHD is the most frequent cardiovascular disease present during pregnancy (75–82%) [
An unrepaired PDA is a risk factor for IE, and when it occurs, the vegetation is often on the pulmonary artery side of the PDA [
IE involving the pulmonic valve is rare. The estimated incidence of IE associated with PDA was reported to be 1% per year with the decline in recent years attributed to early treatment with routine closure of PDA, improved dental care, and prevalent use of antibiotics both for prophylaxis and for IE treatment [
There have been several case reports on IE involving either the pulmonary artery or the pulmonic valve, but their outcomes have either been unknown as the patient was lost to follow-up [
A previous IE is a significant risk factor that predisposes to IE recurrence. A prospective cohort study by Alagna in 2013 reported a 4.8% rate of repeat IE. A previous IE was one of the associated risk factors, with odds ratio of 2.8 (95% CI 1.6-5.4) [
There is no strong recommendation for the closure of a PDA to prevent an initial attack especially for small or silent PDA [
Resolution of the vegetation after antibiotic treatment is one of the indications of successful treatment of IE. However, a 1994 retrospective study by Vuille et al. describing the natural course of vegetations after medical therapy found that out of 41 vegetations, 29 vegetations persisted at the end of treatment (59% of which had no significant change in size, and 52% appeared denser). This led to the conclusion that despite successful medical treatment, persistence of vegetations is still commonly demonstrated echocardiographically and that treatment of IE should be guided by the clinical evolution or response to therapy, rather than the echocardiographic changes of a vegetation [
This case report has been presented in the following conferences: (i) poster presentation, Echo ASE ASEAN Symposium, Manila, Philippines, March 2018; (ii) poster presentation, Asian Pacific Society of Cardiology Congress, Taipei, Taiwan, May 2018; and (iii) third place, oral presentation, Philippine General Hospital Annual Research Forum, October 2018.
The authors declare that there is no conflict of interest regarding the publication of this paper.