ABSTRACT
We report a case of severe outflow graft infection following left ventricular assist device (LVAD) implantation. A 51-year old male LVAD patient was readmitted to our hospital presenting signs of systemic infection. One year previously, LVAD implantation (HeartMate3, Abbott, Chicago, IL, USA) with concomitant patent foramen ovale closure had been performed in the context of end-stage heart failure due to dilative cardiomyopathy (INTERMACS III). The indication for LVAD-therapy was bridge-to-candidacy, since the patient did not instantly fulfill all criteria for cardiac transplantation. At admission, a PET-CT scan unveiled fluid accumulation, encircling the outflow-graft prosthesis (SUVmax 10.5) with contrast-enhancement involving the intrathoracic driveline (SUVmax 11.2). Since cardiac transplantation was not feasible, the patient underwent surgical revision. In the first step, redo sternotomy was performed with local debridement, including jet lavage. Intraoperative swabs confirmed bacterial infection with staphylococcus aureus. Following this, the patient underwent negative pressure wound therapy (NPWT) with instillation using the V.A.C. VERAFLO system (KCI-3M, San Antonio, TX, USA) for a total of 19 days. Due to the severity of infection, local bacteriophage application was performed within the wound closure. In order to concentrate phage therapy at the infection site, phages were applied using a novel semi-fluid galenic. After wound closure, the patient was discharged with an uneventful course. A control PET-CT scan 3 months after discharge showed a significant decrease in infection (outflow graft: SUVmax 7.2, intrathoracic driveline: SUVmax 3.0) correlated with contrast enhancement. Bacterial infection of intrathoracic VAD components represents a severe and potentially life-threatening complication. If cardiac transplantation is not feasible, complex wound management strategies are required. Local bacteriophage therapy might be a promising addition to already established therapeutical options. In order to improve bacteriophage retention at the wound site, application of a viscous galenic might be beneficial.
ABSTRACT
OBJECTIVE: To investigate the interrelationship between cardiac surgery, age, circulating concentrations of the vitamin D hormone 1,25-dihydroxyvitamin D, and clinical outcome. DESIGN: Prospective, monocentric, two-arm parallel study. SETTING: Tertiary Heart and Diabetes Center in the Federal State of North Rhine-Westphalia, Germany. PATIENTS: Twenty-nine cardiac surgical patients aged ≤ 65 yrs and 30 patients ≥ 75 yrs. MEASUREMENTS: We assessed 1,25-dihydroxyvitamin D and other biochemical parameters of mineral metabolism (calcium, phosphate, 25-hydroxyvitamin D, and parathyroid hormone), various inflammatory markers (C-reactive protein, interleukin-6 and 8), and different immunological parameters (CD4 and CD8 cells, monocyte HLA-DR expression). We collected blood samples preoperatively, immediately after surgery, and on postoperative days 1, 5, and 30. In addition, we assessed adverse outcome until discharge as a composite of myocardial infarction, low cardiac output syndrome, infection, stroke, or in-hospital death. RESULTS: There were significant transient cardiac surgery-related fluctuations in 1,25-dihydroxyvitamin D and the aforementioned parameters of mineral metabolism, inflammation, and immune status. Compared to younger patients, older patients had consistently lower 1,25-dihydroxyvitamin D and phosphate levels (p = .013 and p = .036, respectively) and significantly higher interleukin 6 and 8 levels (p = .008 and p < .001, respectively). Circulating 1,25-dihydroxyvitamin D was directly related to glomerular filtration rate (R(2) = .227; p < .001) and inversely related to interleukin 6 (R(2) = .105; p = .012). The rate of adverse outcome tended to be higher in older than in younger patients (20.0% vs. 3.5%; p = .081). In risk score-adjusted logistic regression analysis, adverse outcome risk decreased by 7.7% (SE: 3.7%) for each pmol/L increment in 1,25-dihydroxyvitamin D (p = .037). CONCLUSIONS: Circulating 1,25-dihydroxyvitamin D levels fluctuate in relation to cardiac surgery. Low 1,25-dihydroxyvitamin D levels are associated with inflammatory processes and age-related differences in clinical outcome. Future studies should determine whether therapies aimed at treating low 1,25-dihydroxyvitamin D levels can improve the outcome in older cardiac surgery patients.
