Bansi Koul

Endovascular repair of descending thoracic aortic aneurysms: an early experience with intermediate-term follow-up

PURPOSE The purpose of this study was to report an initial experience with the endovascular repair of descending thoracic aortic aneurysm. Complications and intermediate-term morphologic changes were identified with the intent of altering patient selection and device design. METHODS Endografts were placed into 25 patients at high-risk for conventional surgical repair over a 3(1/2)-year period. Devices were customized on the basis of preoperative imaging information. Follow-up computed tomography scans were obtained at 1, 3, 6, and 12 months and yearly thereafter. Additional interventions occurred in the setting of endoleaks, migration, and aneurysm growth. RESULTS The overall 30-day mortality rate was 20% (12.5% for elective cases; 33% for emergent cases). There were 3 conversions to open repair. Neurologic deficits developed in 3 patients; 1 insult resulted in permanent paraplegia. Neurologic deficits were associated with longer endografts (P =.019). Three endoleaks required treatment, and 1 fatal rupture of the thoracic aneurysm treated occurred 6 months after the initial repair. Migrations were detected in 4 patients. The maximal aneurysm size decreased yearly by 9.15% (P =.01) or by 13.5% (P =.0005) if patients with endoleaks (n = 3 patients) were excluded. Both the proximal and distal neck dilated slightly over the course of follow-up (P =.019 and P =.001, respectively). The length of the proximal neck was a significant predictor of the risk for endoleakage (P =.02). CONCLUSION The treatment of descending thoracic aortic aneurysms with an endovascular approach is feasible and may, in some patients, offer the best means of therapy. Early complications were primarily related to device design and patient selection. All aneurysms without endoleaks decreased in size after treatment. Late complications were associated with changing aneurysm morphologic features and device migration. The morphologic changes remain somewhat unpredictable; however, alterations in device design may result in improved fixation and more durable aneurysm exclusion.

Clinical transplantation of initially rejected donor lungs after reconditioning ex vivo.

BACKGROUND A major problem in clinical lung transplantation is the shortage of donor lungs. Only about 20% of donor lungs are accepted for transplantation. A method to evaluate and recondition lungs ex vivo has been tested on donor lungs that have been rejected for transplantation. METHODS The donor lungs were reconditioned ex vivo in an extracorporeal membrane oxygenation (ECMO) circuit with STEEN solution (Vitrolife AB, Kungsbacka, Sweden) mixed with erythrocytes. The hyperoncotic solution dehydrates edematous lung tissue. Functional evaluations were performed with deoxygenated perfusate by varying the inspired fraction of oxygen. After the reconditioning, the lungs were kept immersed at 8 degrees C in extracorporeal membrane oxygenation until transplantation was performed. RESULTS Six of nine initially rejected donor lungs were reconditioned to acceptable function, and in six recipients, double lung transplantation was performed. Three-month survival was 100%. One patient has since died due to sepsis after 95 days, and one due to rejection after 9 months. Four recipients are alive and well without any sign of bronchiolitis obliterans syndrome 24 months after the transplantation. CONCLUSIONS The result from the present study is promising, and we continue to transplant reconditioned lungs.

Comparative outcome of double lung transplantation using conventional donor lungs and non-acceptable donor lungs reconditioned ex vivo

A method to evaluate and recondition lungs ex vivo has been tested on donor lungs that have been rejected for transplantation. In the present paper, we compare early postoperative course between the six patients who received reconditioned lungs and the patients who received conventional donor lungs during the same period of time. During 2006 and 2007, a total of 21 patients underwent double sequential lung transplantation at the University Hospital of Lund. Six of those patients received reconditioned lungs. The other 15 patients received conventional donor lungs for transplantation without reconditioning ex vivo. The results are presented as median and interquartile range. Time in intensive care unit (days) between recipients of reconditioned lungs [13 (5-24) days], and recipients of conventional donor lungs [7 (5-12) days], P=0.44. Total hospital stay after transplantation (days) between recipients of reconditioned lungs [52 (47-60) days] and recipients of conventional donor lungs [44 (37-48) days], P=0.9. Ex vivo lung evaluation and reconditioning might not prolong early postoperative course in double lung transplantation. However, given the small number of patients, there might be a failure to detect a difference between the two groups.

The feasibility of left ventricular mechanical support as a bridge to cardiac recovery

To study the achievability of device weaning in patients receiving left ventricular assist devices (LVADs) as a bridge to transplantation.

HeartMate Left Ventricular Assist Device as Bridge to Heart Transplantation

BACKGROUND Because of the limited supply of donor hearts, prospective recipients continue to die while on the waiting list for heart transplantation. Use of long-term mechanical circulatory support devices as a bridge to transplantation may reduce this mortality. However, with the present state of technology, continued clinical evaluation of the various long-term, mechanical circulatory support devices available is mandatory. METHODS Sixteen patients were bridged with the HeartMate left ventricular assist device (LVAD) to heart transplantation for New York Heart Association functional class IV cardiac failure. Twelve pneumatic and six electric devices were used. The mean cardiac index and the mean pulmonary vascular resistance of the patient cohort were 1.71 x min(-1) x m(-2) and 3.1 Wood units, respectively. RESULTS The mean LVAD support time per transplanted patient was 237 days, with a cumulative LVAD support time of about 7.2 years. Bleeding was the main operative and postoperative complication. Two patients suffered from neurologic complications and there were two major incidents of device malfunction. Twelve patients (75%) now have received a transplant, 3 (19%) are awaiting a transplant, and in 1 patient (6%), the device was explanted after spontaneous left ventricular recovery. Eleven of the 12 patients who received a transplant are alive and doing well. The HeartMate LVAD gave adequate circulatory support over extended periods of time and reversed the vital organ dysfunction. Since the start of the LVAD program, only 1 patient has died on our heart transplantation waiting list, compared to nine deaths in the 2 preceding years. CONCLUSIONS The HeartMate LVAD bridge to heart transplantation can be performed with low post-LVAD implantation and posttransplantation mortality and offers 1- and 2-year posttransplantation actuarial survival rates comparable to those for nonbridged heart transplant recipients.

Transcatheter closure of post-infarction ventricular septal defect with the Amplatzer Septal occluder device

There is an 80-90% mortality rate within the first 2 months of the occurrence of a post-infarction ventricular septal defect (VSD) with medical treatment alone. The muscular VSD presents a technical problem for the surgeon. Surgical treatment was unsuccessful in two patients. They were treated successfully using the Amplatzer Septal Occluder, with improvement in their condition.There is an 80-90% mortality rate within the first 2 months of the occurrence of a post-infarction ventricular septal defect (VSD) with medical treatment alone. The muscular VSD presents a technical problem for the surgeon. Surgical treatment was unsuccessful in two patients. They were treated successfully using the Amplatzer Septal Occluder, with improvement in their condition.

Pulmonary sequelae of prolonged total venoarterial bypass: evaluation with a new experimental model

Total normothermic venoarterial bypass was established in 6 healthy pigs over a period of 18 hours. A heparin-coated closed extracorporeal system was used and no heparin was administered systemically. During the bypass period the main pulmonary artery was occluded and the heart was maintained in a beating state. All the animals maintained stable hemodynamics and normal blood gases during the entire period of bypass. In the postbypass period, the central hemodynamics continued to be stable while the arterial oxygen tension (inspired oxygen fraction = 0.21) decreased significantly (p less than or equal to 0.05). The total body oxygen uptake, on the other hand, remained unaltered. All the animals died within 4 hours after weaning off the venoarterial bypass circuit on account of pulmonary edema in 2 and cardiac arrest in 4. Death was preceded by progressive pulmonary hypertension and lactacidosis in all the animals. Histological examination of the lungs showed pulmonary parenchymal damage ranging from interstitial edema to intraalveolar hemorrhage and parenchymal necrosis involving more than 80% of the pulmonary parenchyma. A normothermic total venoarterial bypass of 18 hours duration or more produces pulmonary edema of varying severity, pulmonary hypertension, pulmonary parenchymal necrosis, and lactacidosis in healthy juvenile pigs, resulting uniformly in their death. Despite these sequelae the systemic arterial hypoxemia may only be mild to moderate.

How to Recondition Ex Vivo Initially Rejected Donor Lungs for Clinical Transplantation: Clinical Experience from Lund University Hospital

A major problem in clinical lung transplantation is the shortage of donor lungs. Only about 20% of donor lungs are accepted for transplantation. We have recently reported the results of the first six double lung transplantations performed with donor lungs reconditioned ex vivo that had been deemed unsuitable for transplantation by the Scandiatransplant, Eurotransplant, and UK Transplant organizations because the arterial oxygen pressure was less than 40 kPa. The three-month survival of patients undergoing transplant with these lungs was 100%. One patient died due to sepsis after 95 days, and one due to rejection after 9 months. Four recipients are still alive and well 24 months after transplantation, with no signs of bronchiolitis obliterans syndrome. The donor lungs were reconditioned ex vivo in an extracorporeal membrane oxygenation circuit using STEEN solution mixed with erythrocytes, to dehydrate edematous lung tissue. Functional evaluation was performed with deoxygenated perfusate at different inspired fractions of oxygen. The arterial oxygen pressure was significantly improved in this model. This ex vivo evaluation model is thus a valuable addition to the armamentarium in increasing the number of acceptable lungs in a donor population with inferior arterial oxygen pressure values, thereby, increasing the lung donor pool for transplantation. In the following paper we present our clinical experience from the first six patients in the world. We also present the technique we used in detail with flowchart.

Three decades of heart transplantation in Scandinavia: long-term follow-up

Heart transplantation (HTx) has become a standard treatment for patients with end‐stage heart disease. The aim of this study was to report the long‐term outcome after HTx in Scandinavia.

Veno-venous extracorporeal membrane oxygenation with a heparin-coated system in adult respiratory distress syndrome

Three patients with adult respiratory distress syndrome were treated with veno-venous extracorporeal membrane oxygenation, ECMO, using a heparin-coated system for 8, 12 and 34 days, respectively. Despite extracorporeal blood flow of 4-5 l/min, the patients were ventilator-dependent in the initial period of ECMO. Two of the three patients showed bleeding diatheses despite only slightly elevated activated partial thromboplastin time (APTT). Blood platelet count followed a variable course and serum fibrinogen was normal. Acute pulmonary hypertensive crises, fatal systemic infection, recurrent pneumothorax and plasma leakage from the oxygenators were other main complications during ECMO. Two of the three patients survived, and follow-up showed that severely damaged lungs, if supported in the acute phase, can recover sufficiently to permit normal living.