M. Pichlmaier

Percutaneous extracorporeal life support for patients in therapy refractory cardiogenic shock: initial results of an interdisciplinary team

OBJECTIVES Therapy refractory cardiogenic shock is associated with dismal outcome. Percutaneous implantation of an extracorporeal life support (ECLS) system achieves immediate cardiopulmonary stabilization, sufficient end-organ perfusion and reduction of subsequent multiorgan failure (MOF). METHODS Forty-one patients undergoing percutaneous ECLS implantation for cardiogenic shock from February 2012 until August 2013 were retrospectively analysed. Mean age was 52 ± 13 years, 6 (15%) were female. Mean pH values obtained before ECLS implantation were 7.15 ± 0.24, mean lactate concentration was 11.7 ± 6.4 mmol/l. Levels obtained 6 h after ECLS implantation were 7.30 ± 0.14 and 8.7 ± 5.0 mmol/l, respectively. In 23 patients (56%) cardiogenic shock resulted from an acute coronary syndrome in 13 (32%) from cardiomyopathy, in 5 (12%) from other causes. Twenty-seven (66%) had been resuscitated, in 14 (34%) implantation was performed under ongoing cardiopulmonary resuscitation (CPR). Of note, 97% of the acute coronary syndrome patients underwent percutaneous coronary intervention (PCI) either before ECLS implantation or under ECLS support. Extracorporeal life support implantation was performed on scene (Emergency Department, Cath Lab, Intensive Care Unit) by a senior cardiac surgeon and a trained perfusionist, in 8 cases (20%) in the referring hospital. RESULTS Thirty-day mortality was 51% [21 patients, due to MOF (n = 14), cerebral complications (n = 6) and heart failure (n = 1)]. Logistic regression analysis identified 6-h pH values as an independent risk factor of 30-day mortality (P < 0.001, OR = 0.000, 95% CI 0.000-0.042). Neither CPR nor implantation under ongoing CPR resulted in significant differences. In 26 cases (63%), the ECLS system could be explanted, after mean support of 169 ± 67 h. Seven of these patients received cardiac surgery [ventricular assist device implantation (n = 4), heart transplantation (n = 1), other procedures (n = 2)]. CONCLUSIONS Due to the evolution of transportable ECLS systems and percutaneous techniques implantation on scene is feasible. Extracorporeal life support may serve as a bridge-to-decision and bridge-to-treatment device. Neurological evaluation before ventricular assist device implantation and PCI under stable conditions are possible. Despite substantial mortality, ECLS implantation in selected patients by an experienced team offers additional support to conventional therapy as well as CPR and allows survival in patients that otherwise most likely would have died. This concept has to be implemented in cardiac survival networks in the future.

When all else fails: extracorporeal life support in therapy-refractory cardiogenic shock

OBJECTIVES No guidelines for mechanical circulatory support in patients with therapy-refractory cardiogenic shock and multiorgan failure including ongoing cardiopulmonary resuscitation (CPR) exist. To achieve immediate cardiopulmonary stabilization, we established an interdisciplinary concept with on-site percutaneous extracorporeal life support (ECLS) implantation. METHODS From February 2012 to November 2014, 96 patients were deemed eligible for ECLS implantation. Establishing ECLS was successful in 87 patients (mean age 54 ± 13 years, 16% female, initial flow 4.4 ± 0.9 l/min). Aetiologies included acute coronary syndromes (n = 52, 60%), cardiomyopathies (n = 25, 29%) and other pathologies. Fifty-nine patients (68%) had been resuscitated, and in 27 (31%), implantation was performed during CPR; 11 patients (13%) were awake at implantation and 20 (23%) underwent implantation in the referring hospital. RESULTS Metabolic parameters differed in non-survivors versus survivors before ECLS implantation (pH 7.15 ± 0.23 vs. 7.27 ± 0.18, P = 0.007; lactate levels 10.90 ± 6.00 mmol/l vs. 8.79 ± 5.78 mmol/l, P = 0.091) and 6 h postimplantation (pH 7.27 ± 0.11 vs. 7.37 ± 0.11, P < 0.001; lactate levels 10.19 ± 5.52 mmol/l vs. 5.52 ± 4.17 mmol/l, P < 0.001). Altogether 44 patients could be weaned, and 9 were bridged to assist device implantation and 1 to heart transplantation. The mean time of support was 6 days, and the 30-day survival rate was 47% (n = 41). CONCLUSIONS ECLS serves as a bridge-to-decision and bridge-to-treatment device. Our interdisciplinary ECLS programme achieved acceptable survival of critically ill patients despite a substantial percentage of patients having been resuscitated and no absolute exclusion criteria. Further studies defining inclusion- and exclusion criteria might additionally improve outcome.

Severe obstructive calcifications affecting the descending and suprarenal abdominal aorta without coexisting peripheral atherosclerotic disease – coral reef aorta

The case of a 58-year-old woman with leg claudication due to a very rare form of atherosclerosis affecting the descending thoracic and abdominal aorta--known as coral reef aorta--without involvement of the femoro-distal vessels is reported. The patient was treated with a polyester bifurcation graft from the proximal descending aorta to both common iliac arteries via a left dorsal mini-thoracotomy and a second left retroperitoneal approach. This unusual approach was chosen instead of direct aortic replacement in order to prevent paraplegia. In case of future visceral or left renal malperfusion the diseased artery can be connected to the prosthesis directly or by the use of an additional bypass graft. This would not be the case with a conventional axillo-bifemoral graft.

Treatment of acute aortic dissection type A (AADA): technical considerations.

Aortic dissection is one of the the most common and lethal catastrophes involving the aorta. Speedy diagnosis, as well as appropriate therapy are essential for survival of the patients. Because the clinical presentation in patients suffering AADA can differ substantially, discussion concerning specific surgical therapy remains controversial. This implies questions regarding the treatment of the aortic root as well as the aortic arch and the proximal descending aorta. The current manuscript raises important issues regarding surgical treatment of AADA patients which are discussed in the light of the institutional policy in the authors department.

The relevance of 18F-fluorodeoxyglucose positron emission tomography/computed tomography imaging in diagnosing prosthetic graft infections post cardiac and proximal thoracic aortic surgery

OBJECTIVES Diagnosis of prosthetic graft infection after cardiac and proximal aortic surgery is a challenge. Besides technical considerations, redo surgery is associated with substantial morbidity and mortality. Therefore, an accurate diagnosis is mandatory. We report on our experience with hybrid 18-fluorodeoxyglucose positron emission tomography ((18)F-FDG PET)/computed tomography (CT) imaging, which is increasingly used to diagnose infections in the detection of graft infection after cardiac surgery. METHODS Twenty-six patients who underwent (18)F-FDG PET/CT imaging after cardiac surgery between February 2010 and September 2014 for suspected graft infection were retrospectively analysed (81% male, age 54.3 ± 13.7 years). PET/CT imaging was performed 36.5 ± 70.5 (0.5-300) months after surgery. 2 patients (8%) had undergone aortic valve replacement (concomitant ascending and proximal arch replacement in 1), 1 (4%) aortic root reconstruction, 9 (35%) aortic root replacement (concomitant partial arch in 4, arch replacement and postoperative TEVAR in 1), 2 (8%) ascending aortic and partial arch replacement and 2 (8%) ascending aortic replacement along with frozen elephant trunk. In 10 (38%), more than one previous cardiac surgical procedure had been performed. Maximum standardized uptake values (SUVmax) were obtained for all patients. If the patients were reoperated on, the final diagnosis was derived from intraoperative findings and/or microbiological results. Otherwise, the longest clinical follow-up available served as a reference. RESULTS Conventional CT was positive for infection in 13 cases (50%). In 22 (85%), PET was indicative of infection (SUVmax 10.5 ± 4.1). PET did not only confirm true-positive CT results in all but 1 case; in almost 30%, it provided substantial additional diagnostic information in comparison with CT alone. Receiver operating characteristic analysis identified an SUVmax of 7.25 to achieve maximum sensitivity (89%) and specificity (100%) in prediction of infection. Twelve patients (46%) required redo surgery for graft infection; in 1 additional patient (4%), sternal re-fixation was necessary. Furthermore, 2 patients had to be reoperated on for torn-out anastomosis and paraprosthetic perfusion (8%). CONCLUSIONS PET provides functional data, confirms a CT diagnosis and may even increase diagnostic sensitivity in comparison with CT alone in selected cases. Specificity can be compromised by postoperative changes or chronic inflammatory reactions induced by the graft. CT and/or echocardiography should remain the first diagnostic step in case of a suspected infection because of their broad and fast availability. If confirmation is needed or diagnosis is not achievable using conventional methods, PET might be chosen as the next modality to gain additional information in experienced centres.

Significance of infection markers and microbiological findings during tissue processing of cryopreserved arterial homografts for the early postoperative course

BACKGROUND To evaluate homograft implantation for the urgent treatment of vascular infections on the basis of the course of infection using microbiological findings in perioperatively obtained specimens and during homograft processing. PATIENTS AND METHODS 85 patients were treated with cryopreserved homografts from 2004-2007. The microbiological findings of the decontamination process of homografts in the tissue bank were evaluated. The perioperative infection profile (microorganisms, CRP, leukocytes, body temperature) of the patients was analysed. RESULTS Complete microbiological and clinical follow-up for the postoperative course was available for 35 patients, who were treated with homografts from the same tissue bank and finally included into this study. 55 cryopreserved homografts were implanted. 35/55 (64%) homografts were positive for microorganisms before decontamination. 3/35 (9%) homografts remained positive after the decontamination. 33 patients were operated for prosthetic graft infection and 2 for an infiltration of a large vessel from neighbouring malignant disease. The most common infection agent was Staphylococcus aureus. Thirty-day mortality was 20% (7/35). Only in 4/35 (11%) patients were the microorganisms of the intraoperative swabs also detected during the postoperative course. The microorganisms were ORSA, Enterococcus faecium, Enterobacter aerogenes and Burkholderia cepacia. The patient with ORSA infection died on POD 11 from multiple organ failure and all other patients recovered. None of the postoperative swabs showed the homograft predecontamination microorganisms. Interestingly, a significant association (P = 0.003) between C-reactive protein increase two weeks after surgery and donor-recipient ABO mismatch was found. CONCLUSIONS The implantation of homografts following the established decontamination is an alternative urgent therapeutic option in vascular infections with encouraging outcomes. The absence of the predecontamination focus in the postoperative specimens of patients, suggests that the postoperative course and outcomes show no strong relation to potential homograft contamination prior to the decontamination process.

New insights into valve-related intramural and intracellular bacterial diversity in infective endocarditis

Aims In infective endocarditis (IE), a severe inflammatory disease of the endocardium with an unchanged incidence and mortality rate over the past decades, only 1% of the cases have been described as polymicrobial infections based on microbiological approaches. The aim of this study was to identify potential biodiversity of bacterial species from infected native and prosthetic valves. Furthermore, we compared the ultrastructural micro-environments to detect the localization and distribution patterns of pathogens in IE. Material and methods Using next-generation sequencing (NGS) of 16S rDNA, which allows analysis of the entire bacterial community within a single sample, we investigated the biodiversity of infectious bacterial species from resected native and prosthetic valves in a clinical cohort of 8 IE patients. Furthermore, we investigated the ultrastructural infected valve micro-environment by focused ion beam scanning electron microscopy (FIB-SEM). Results Biodiversity was detected in 7 of 8 resected heart valves. This comprised 13 bacterial genera and 16 species. In addition to 11 pathogens already described as being IE related, 5 bacterial species were identified as having a novel association. In contrast, valve and blood culture-based diagnosis revealed only 4 species from 3 bacterial genera and did not show any relevant antibiotic resistance. The antibiotics chosen on this basis for treatment, however, did not cover the bacterial spectra identified by our amplicon sequencing analysis in 4 of 8 cases. In addition to intramural distribution patterns of infective bacteria, intracellular localization with evidence of bacterial immune escape mechanisms was identified. Conclusion The high frequency of polymicrobial infections, pathogen diversity, and intracellular persistence of common IE-causing bacteria may provide clues to help explain the persistent and devastating mortality rate observed for IE. Improved bacterial diagnosis by 16S rDNA NGS that increases the ability to tailor antibiotic therapy may result in improved outcomes.

Predictors of cerebrovascular events at mid-term after transcatheter aortic valve implantation – Results from EVERY-TAVI registry☆

BACKGROUND Clinical relevant cerebrovascular events (CVE) following transcatheter aortic valve implantation (TAVI) still remain a devastating complication associated with mortality and severe impairments. Therefore, identification of particularly modifiable predictors of this complication is clinically relevant and an important step for planning preventive strategies. METHODS A total of 985 patients who underwent trans-femoral TAVI for aortic valve stenosis in our institution from February 2008 to January 2015 were considered. The influence of demographics, clinical and procedural data on the occurrence of CVE was assessed with a competing risk model with death as competing event. Clinical events were defined according to VARC-2 criteria. RESULTS At a median follow-up of 838days, 95% CI 807-892, 59 patients experienced any CVE (5.9%) and the overall cumulative mortality rate was 46.1%. CVEs mainly occur later than 30days after TAVI (47.5%), 88.1% of them were of ischemic origin and 52.5% were disabling events. Independent predictors of CVEs were age (hazard ratio 1.05; 95% CI 1.01 to 1.09), history of CVE (hazard ratio 2.54; 95% CI 1.39 to 4.63) and use of balloon post-dilation (hazard ratio 1.85; 95% CI 1.08 to 3.18). CONCLUSION In patients undergoing TAVI incidence of clinically relevant CVEs is frequent with half of the events occurring after the first 30days post-TAVI. Identification of balloon post-dilation as the only modifiable predictor of CVE risk at mid-term, urges its cautious performance after prosthesis implantation. CLINICALTRIALS. GOV IDENTIFIER NCT02289339.

Homograft patch repair in carotid artery rupture

The case of a 24-year-old man with a rupture of the left common carotid artery and history of intravenous drug abuse is presented. Due to absence of a suitable autologous vein segment the carotid bulb was repaired with a human allograftpatch.

Patient management in aortic arch surgery

Summary Aortic arch surgery requires complex patient management beyond the manual replacement of the diseased vessel. These procedures include (i) a thorough and pathologically adjusted preoperative evaluation, (ii) initiation and control of cardiopulmonary bypass, (iii) cerebral protection strategies and (iv) techniques to protect the abdominal end organs during prolonged operations. Due to the complexity of aortic arch procedures, multimodal real-time surveillance is required during all stages of the operation. Although having the patient survive the operation is the major goal, further observation is necessary because of the chronicity of the disease. This review summarizes specific aspects of patient management during and after operations requiring periods of circulatory arrest, without necessarily referring to all studies on this topic. The pros and cons of different strategies are weighed against each other, including the personal experience of the authors. A number of questions are raised without providing a ‘right’ or ‘wrong’ answer. We show that a number of different well-established strategies can result in comparable excellent long-lasting surgical results.