Axel Haverich

Intramural Hematoma of the Aorta

Background—Aortic intramural hematoma (IMH) is a variant of overt aortic dissection. The predictors of progression of IMH to dissection and rupture are still unknown, and strategies for management are not established. Methods and Results—A multicenter study was conducted comprising 66 patients with IMH and hospital admission ≤48 hours after onset of initial symptoms. Among these, progression to aortic dissection or rupture occurred in 30 (45%) and death occurred in 13 (20%) patients within 30 days. Late progression was noted in 14 (21%) and death in 11 (17%) patients, yielding a 1-, 2-, and 5-year survival of 76%, 73%, and 43%, respectively. In a set of 9 variables, multivariate analysis identified IMH location in the ascending aorta (type A;P =0.02) and moderately ectatic aortic diameters (49±13 mm with progression versus 57±16 mm without progression;P =0.03) as independent predictors of early progression. In type A IMH, early mortality was 8% with swift surgery versus 55% without surgery (P =0.004). The risk of late progression of IMH was independently associated with age at index diagnosis (P =0.01) and absence of &bgr;-blocker therapy during follow-up (P =0.03). Kaplan-Meier analysis confirmed improved 1-year survival of IMH with &bgr;-blocker therapy (95% versus 67% without &bgr;-blockers;P =0.004). Conclusions—Regardless of aortic diameter, IMH of the ascending aorta (type A) is at high risk for early progression, and, thus, undelayed surgical repair should be performed. Moreover, oral &bgr;-blocker therapy may improve long-term prognosis of IMH independent of anatomical location.

Hypothermic circulatory arrest during ascending and aortic arch surgery: the theoretical impact of different cerebral perfusion techniques and other methods of cerebral protection.

Operations on the thoracic aorta using hypothermic circulatory arrest are still associated with significant morbidity and mortality due to neurological complications. During the last decades, different cerebral protection techniques have been introduced into clinical practice to reduce the incidence of such complications. Furthermore clinical as well as basic researches have been performed to improve the outcome after these operations. Currently different cerebral perfusion methods are in clinical use and the superiority of one or the other method is a matter of controversial discussion. This review has been undertaken to evaluate the theoretical impact of these different methods of cerebral protection. Based on the experience of the authors the pros and cons are discussed with clinical and experimental reports from the literature.

Decade of Aortic Valve Sparing Reimplantation Are We Pushing the Limits Too Far

Background—This single center study assesses the outcome of aortic valve sparing reimplantation (AVS) in 284 consecutive patients who were operated on for various indications during the last 11 years. Methods and Results—From July, 1993, to July, 2004, 284 patients underwent AVS. Mean age was 53±16 (range 8 to 84) years. Of the 284 patients, 184 were male (64.8%) and 54 (19%) experienced Marfan’s syndrome. Acute aortic dissection Stanford type A was present in 53 patients (19%) and a bicuspid aortic valve was present in 17 patients (6%). Concomitant arch replacement was necessary in 120 patients (42%). Additional procedures were performed in 66 patients (23.2%). Mean follow-up time was 41±32 (range 0 to 130) months. The 30-day mortality was 3.2% overall, 11.3% in emergency patients, and 1.3% in elective patients. Mean bypass time was 174±48 (range 90 to 440) minutes and aortic cross clamp time was 132±33 (range 64 to 283) minutes. In patients undergoing arch replacement, circulatory arrest was 25±17 (range 7 to 99) minutes. Rethoracotomy for bleeding was required in 4.6% of patients. During follow-up, there were 20 (7.3%) late deaths. Reoperation of the reconstructed valve was required in 15 patients (5.3%); underlying reasons were endocarditis (n=4) and aortic insufficiency (n=11) requiring aortic valve replacement. Average grade of aortic insufficiency increased significantly from 0.23±0.46 postoperatively to 0.34±0.59 at latest evaluation (P=0.026). Two patients experienced a transient ischemic attack early postoperatively; no further thromboembolic complications were noticed. The majority of patients (96%) presented with a favorable exercise tolerance at last contact. Conclusions—The aortic valve reimplantation technique leads to excellent clinical outcome in patients with various pathologies. Lack of anticoagulation and favorable durability should encourage the extension of indications for this technique.

Hybrid Endograft for One-Step Treatment of Multisegment Disease of the Thoracic Aorta

PURPOSEnAt present, a two-step surgical approach is necessary to treat patients with coexistent pathologic conditions involving the proximal and descending thoracic aorta. A hybrid endograft is described here that enables such treatment during a single operation.nnnMATERIALS AND METHODSnThe Chavan-Haverich endograft consists of a Dacron vascular prosthesis with stainless-steel stents affixed at its distal end. After approval by the institutional review board, the endograft was prospectively implanted in 22 patients with multisegment thoracic aortic disease (13 men, nine women; median age, 64 years). Eleven patients had type A dissections (one acute, 10 chronic), four had a chronic type B dissection, and seven had atherosclerotic aneurysms of the ascending aorta or aortic arch as well as of the descending aorta. Of these patients, 11 additionally required aortic valve replacement or coronary artery bypass grafting. Via median sternotomy, the aortic arch was opened in circulatory arrest. After antegrade deployment of the stent-containing portion in the descending aorta, the proximal non-stent-containing endograft was used to reconstruct the aortic arch. Median follow-up was 14 months.nnnRESULTSnEndograft implantation was successful in all but one patient. Complications included neurologic deficits that were transient in one case and lasting in two, two cases of vocal cord paralysis, and one death. In all patients with atherosclerotic aneurysms who received the endograft (six of seven), aneurysm thrombosis was noted at follow-up. In aortic dissections, partial or complete false-lumen thrombosis to the level of the stents occurred in all patients. None of the patients showed a progressive widening of the descending aorta.nnnCONCLUSIONnThe Chavan-Haverich endograft enables one-step treatment of multisegment pathologic conditions affecting the thoracic aorta that otherwise would require two or more operations.

Endoluminal treatment of aortic dissection

Aortic dissection is most often a catastrophic medical emergency which, if untreated, can be potentially fatal. The intention of therapy in patients with aortic dissection is to prevent aortic rupture or aneurysm formation as well as to relieve branch vessel ischaemia. Patients with aortic dissection are often poor candidates for anaesthesia and surgery and the surgical procedure itself is challenging requiring thoracotomy, aortic cross clamping, blood transfusion as well as prolonged hospital stay in some cases. Operative mortality is especially high in patients with critical mesenteric or renal ischaemia. The past decade has experienced the emergence of a number of interventional radiological or minimally invasive techniques which have significantly improved the management of patients with aortic dissection. These include stent grafting for entry site closure to prevent aneurysmatic widening of the false lumen as well as percutaneous techniques such as balloon fenestration of the intimal flap and aortic true lumen stenting to alleviate branch vessel ischaemia. False lumen thrombosis following entry closure with stent grafts has been observed in 86–100% of patients, whereas percutaneous interventions are able to effectively relieve organ ischaemia in approximately 90% of the cases. In the years to come, it is to be expected that these endoluminal techniques will become the method of choice for treating most type-B dissections and will assist in significantly reducing the number of open surgical procedures required for type-A dissections. The intention of this article is to provide an overview of the current status of these endoluminal techniques based on our own experience as well as on a review of the relevant literature.

The frozen elephant trunk technique

The so-called frozen elephant trunk technique is adapted from the classical elephant trunk technique first described by H.G. Borst in 1983 and allows the repair of concomitant aortic arch and proximal descending aortic aneurysms in a single stage. A hybrid vascular graft consisting of a conventional tube graft with an endovascular stented graft at the distal end is utilised to achieve a blood-tight seal in the descending aorta that cannot easily be accessed directly from an anterior approach. Thus, the concept of a traditional elephant trunk, otherwise completed with a secondary endovascular or surgical procedure, is achieved in one single step. First intra- and postoperative results of this technique in terms of successful exclusion of the proximal descending aortic aneurysm are good and following the learning curve, the prolongation of circulatory arrest and cerebral perfusion, as compared to the traditional elephant trunk procedure, is within minutes and thus acceptable. Currently all patients with thoracic aneurysms extending from the arch beyond the left subclavian artery are evaluated for this treatment at our institution. Furthermore, acute aortic dissections (type A and B) are an area of intensive clinical evaluation at present.

Intra-vital Fluorescence Microscopy for Intra-myocardial Graft Detection Following Cell Transplantation

Introduction:xa0The aim of our study was the development of a potentially clinically applicable approach, which allows for intra-myocardial detection of the transplanted cells without the need for collection of tissue samples. Intra-myocardial transplantation of myocytes and bone marrow derived cells is currently under clinical evaluation as a therapy of heart failure. A major limitation of all clinical studies for myocardial restoration through cell transfer is the inability to track the fate of the transplanted cells. Methods:xa0Fetal canine cardiomyocytes were labelled with the non-toxic fluorescent membrane dye Vybrant® CM-DiI and injected into the free wall of the left ventricle of six adult mongrel dogs. For subsequent tracking of the cellular graft, the dogs were re-operated and an intra-vital microscope was mounted above the exposed heart within the thorax. Results:xa0Two months following cell transplantation, the fluorescent graft was visible by intra-vital microscopy using a 10× magnification. Histological studies served as microscopic control and confirmed the presence of DiI-labelled cells at the site of injection. Connexin 43 immunoreactivity was visible at junctional complexes between donor and recipient cells, suggesting morphologic coupling as a result of gap junction formation. Conclusions:xa0Our results demonstrate that in vivo detection of transplanted cells in the heart is feasible. Further technical adjustments will facilitate thoracoscopic and therefore less invasive application of this method.

Cardiac surgery in elderly patients

ZusammenfassungMit zunehmendem Anteil älterer Menschen an der Gesamtbevölkerung nimmt das durchschnittliche Alter der am Herzen zu operierenden Patienten zu. Im Rahmen einer Metaanalyse wurde untersucht, ob und unter welchen Bedingungen auch über 80-Jährige von herzchirurgischen Eingriffen profitieren. Die Grundlage bildeten verschiedene Studien, die Kurz- oder Langzeitergebnisse von herzchirurgischen Eingriffen unterschiedlicher Altersgruppen untersuchten. Es zeigte sich, dass über 80-Jährige durchaus mit einem akzeptablem Risiko am Herzen operiert werden können. Darüber hinaus konnte festgestellt werden, dass sowohl die perioperative Mortalität als auch andere postoperative Komplikationen eher von der Komorbidität als vom Alter des Patienten bestimmt werden. Sowohl die Lebensqualität als auch die Lebenserwartung bei Patienten dieser Altersgruppe können durch herzchirurgische Eingriffe verbessert werden.AbstractDue to demographic changes in average life expectancy, the age of patients undergoing cardiac surgery is increasing. We have reviewed the literature to analyse whether and how far octogenarians benefit from cardiac surgical procedures. Different studies analysed the outcome of patients in different age groups after cardiac surgery. Octogenarians can undergo cardiac surgical procedures at a reasonable risk. The perioperative mortality and other postoperative complications are strongly dependent on comorbidities rather than on patients’ age. Elderly patients benefit from improved functional status and quality of life.