Acute Kidney Injury After Heart Transplantation: Risk Factors and Clinical Outcomes.

OBJECTIVE: Acute kidney injury (AKI) requiring renal-replacement therapy (RRT) after heart transplantation (OHT) is common and impairs outcomes. This study aimed to identify independent donor and recipient risk factors associated with RRT after OHT. DESIGN: A retrospective data analysis. SETTING: Data were collected from clinical routines in a maximum-care university hospital. PARTICIPANTS: Patients who underwent OHT. INTERVENTIONS: The authors retrospectively analyzed data from 264 patients who underwent OHT between 2012 and 2021; 189 patients were eligible and included in the final analysis. MEASUREMENTS AND MAIN RESULTS: The mean age was 48.0 ± 12.3 years, and 71.4% of patients were male. Ninety (47.6%) patients were on long-term mechanical circulatory support (lt-MCS). Posttransplant AKI with RRT occurred in 123 (65.1%) patients. In a multivariate analysis, preoperative body mass index >25 kg/m² (odds ratio [OR] 4.74, p < 0.001), elevated preoperative creatinine levels (OR for each mg/dL increase 3.44, p = 0.004), administration of red blood cell units during transplantation procedure (OR 2.31, p = 0.041) and ischemia time (OR for each hour increase 1.77, p = 0.004) were associated with a higher incidence of RRT. The use of renin-angiotensin-aldosterone system blockers before transplantation was associated with a reduced risk of RRT (OR 0.36, p = 0.013). The risk of mortality was 6.9-fold higher in patients who required RRT (hazard ratio 6.9, 95% CI: 2.1-22.6 p = 0.001). Previous lt-MCS, as well as donor parameters, were not associated with RRT after OHT. CONCLUSIONS: The implementation of guideline-directed medical therapy, weight reduction, minimizing ischemia time (ie, organ perfusion systems, workflow optimization), and comprehensive patient blood management potentially influences renal function and outcomes after OHT.

Fluorescence in situ hybridization and polymerase chain reaction to detect infections of cardiac implantable electronic devices.

AIMS: In patients with infections of cardiac implantable electronic devices (CIEDs), the identification of causative pathogens is complicated by biofilm formations and previous antibiotic therapy. In this work, the impact of an additional fluorescence in situ hybridization (FISH), in combination with polymerase chain reaction and sequencing (FISHseq) was investigated. METHODS AND RESULTS: In 36 patients with CIED infections, FISHseq of explanted devices was performed and compared with standard microbiological cultivation of preoperative and intraoperative samples. The mean age was 61.9 (±16.2) years; 25 (69.4%) were males. Most patients (62.9%) had heart failure with reduced ejection fraction. Infections occurred as endoplastits (n = 26), isolated local generator pocket infection (n = 8), or both (n = 2); CIED included cardiac resynchronization therapy defibrillator (n = 17), implantable cardioverter defibrillator (n = 11), and pacemaker (n = 8) devices. The overall positive FISHseq detection rate was 97%. Intraoperatively, pathogens were isolated in 42 vs. 53% in standard cultivation vs. FISHseq, respectively. In 16 of 17 FISHseq-negative patients, the nucleic acid strain DAPI (4',6-diamidino-2-phenylindole) indicated inactive microorganisms, which were partially organized in biofilms (n = 4) or microcolonies (n = 2). In 13 patients in whom no pathogen was identified preoperatively, standard cultivation and FISHseq identified pathogens in 3 (23%) vs. 8 (62%), respectively. For the confirmation of preoperatively known bacteria, a combined approach was most efficient. CONCLUSION: Fluorescence in situ hybridization sequencing is a valuable tool to detect causative microorganisms in CIED infections. The combination of FISHseq with preoperative cultivation showed the highest efficacy in detecting pathogens. Additional cultivation of intraoperative tissue samples or swabs yielded more confirmation of pathogens known from preoperative culture.

Asanguineous Cardiopulmonary Bypass in Infants: Impact on Postoperative Mortality and Morbidity.

BACKGROUND: We routinely start cardiopulmonary bypass (CPB) for pediatric congenital heart surgery without homologous blood, due to circuit miniaturization, and blood-saving measures. Blood transfusion is applied if hemoglobin concentration falls under 8 g/dL, or it is postponed to after coming off bypass or after operation. How this strategy impacts on postoperative mortality and morbidity, in infants weighing ≤ 7 kg? METHODS: Six-hundred fifteen open-heart procedures performed from January 2014 to June 2018 were selected. One-hundred sixty-three patients (26.5%) were transfused on CPB (group 1), while 452 (73.5%) patients were not transfused on CPB (group 2). Operative risk and complexity were similar in both groups. Postoperative mortality and morbidity were compared. Multiple logistic regression was used to detect factors independently associated with outcome. RESULTS: Observed mortality in nontransfused group (0.7% = 3/452) was significantly lower than expected (4.2% = 19/452): p = 0.0007, and much lower than in transfused group (6.7% = 11/163): p < 0.0001. CPB transfusion (p = 0.001) was independently associated with mortality, either acting as the sole factor or in combination with the Society of Thoracic Surgeons morbidity score (p = 0.013). Patients not transfused during CPB required less frequently vasoactive inotropic drugs (p = 0.011) and duration of their mechanical ventilation was shorter (93 ± 134 hours) than for transfused patients (142 ± 170 hours): p = 0.0003. CPB transfusion was an independent determinant factor for morbidity (p = 0.05), together with body weight (p < 0.0001), vasoactive inotropic score (p < 0.0001), CPB duration (p = 0.001), and postoperative transfusion (p = 0.009). CONCLUSION: The strategy of transfusion-free CPB course, feasible in most patients ≤ 7kg, was associated with improved outcome. Asanguineous priming of CPB circuit should become standard, even in neonates and infants.

Bloodless priming of the cardiopulmonary bypass circuit: determinants of successful transfusion-free operation in neonates and infants with a maximum body weight of 7 kg.

We currently perform open-heart procedures using bloodless priming of cardiopulmonary bypass circuits regardless of a patient's body weight. This study presents results of this blood-saving approach in neonates and infants with a body weight of up to 7 kg. It tests with multivariate analysis factors that affect perioperative transfusion. A total of 498 open-heart procedures were carried out in the period 2014-2016 and were analysed. Priming volume ranged from 73 ml for patients weighing up to 2.5 kg to 110 ml for those weighing over 5 kg. Transfusion threshold during cardiopulmonary bypass was 8 g/dl of haemoglobin concentration. Transfusion factors were first analysed individually. Variables with a p-value lower than 0.2 underwent logistic regression. Extracorporeal circulation was conducted without transfusion of blood in 335 procedures - that is, 67% of cases. Transfusion-free operation was achieved in 136 patients (27%) and was more frequently observed after arterial switch operation and ventricular septal defect repair (12/18=66.7%). It was never observed after Norwood procedure (0/33=0%). Lower mortality score (p=0.001), anaesthesia provided by a certain physician (p=0.006), first chest entry (p=0.013), and higher haemoglobin concentration before going on bypass (p=0.013) supported transfusion-free operation. Early postoperative mortality was 4.4% (22/498). It was lower than expected (6.4%: 32/498). In conclusion, by adjusting the circuit, cardiopulmonary bypass could be conducted without donor blood in majority of patients, regardless of body weight. Transfusion-free open-heart surgery in neonates and infants requires team cooperation. It was more often achieved in procedures with lower mortality score.