Donor Left Atrium Research Articles

Correction of Anomalous Pulmonary Venous Return during Heart Transplantation

Introduction The management of incidental cardiac shunts at the time of orthotopic heart transplantation (OHT) is rarely described in literature. We present a case involving surgical correction of a partial anomalous pulmonary venous connection (PAPVC) at the time of OHT. Case Report The patient is a 65-year-old woman with a history of idiopathic dilated cardiomyopathy (diagnosed in 2010), and a PAPVC. She was diagnosed with the PAPVC incidentally after a right heart catheterization. CT angiogram confirmed an anomalous connection of her right superior and middle pulmonary veins to her superior vena cava (SVC). Serial echocardiograms showed a left ventricular ejection fraction of 20 to 25% and mild pulmonary hypertension. Her right atrium and ventricle were mildly dilated in size and her right ventricular function remained normal. In the year preceding her OHT she developed NYHA class III-IV symptoms and frequent episodes of decompensated heart failure, necessitating advanced cardiac therapies. Ultimately she underwent OHT with concomitant PAPVC repair. At the time of transplantation, the recipient's SVC was divided above the anomalous vein and a pericardial patch was applied to the orifice created on the right atrium. The recipient right atrium and interatrial septum were constructed into an atrial baffle with bovine pericardium, which was then anastomosed to the donor left atrium with a surgically created atrial septal defect in the fossa ovalis. Afterwards, the transplantation proceeded using the standard bicaval technique with the donor left atrium connected to recipient left atrium and the atrial baffle. There were no intra-operative complications, and the patient did well post-operatively. Summary PAPVCs typically cause shunting of oxygenated blood to the right atrium. For patients with clinically significant PAPVCs, surgical correction may be necessary and usually involves a Warden procedure, which can require reconstruction of the right atrial appendage. In patients undergoing PAPVC repair at the time of bicaval OHT, the recipient SVC is anastomosed to donor SVC which is simpler technically than atrial reconstruction and offers better outcomes regarding arrhythmias and tricuspid regurgitation. Furthermore, this maintains adequate pulmonary and systemic venous outflow into the atria. To our knowledge, this is the first reported case of PAPVC repair at the time of OHT in the US.

A Patient with Giant Left Atrium Undergoes Orthotopic Heart Transplantation

We present a novel technique for resolving the problem of radical size mismatch at the time of orthotopic transplantation. A 48-year-old man presented with chronic rheumatic heart disease and a giant left atrium. Twenty-three years before, he had undergone mitral valve replacement with a mechanical prosthesis. At the time of the repeated intervention, the volume of his left atrium was 350 mL. Surgical features of the transplantation included approximation of the pulmonary vein ostia by gathering sutures intentionally, in order to decrease the area of the left atrial posterior wall and thereby enable appropriate coaptation with the donor left atrium. After the operation, left atrial volume had been reduced to 60 mL.

Establishment of a novel volume-loaded heterotopic heart transplantation model in rats

BackgroundNon–volume-loaded (NL) donor hearts in the heterotopic heart transplantation model in rats undergo atrophy and thrombus formation in graft cavities after transplantation. The present study aimed to establish a novel model with volume-loaded donor hearts. MethodsWe used Sprague-Dawley rats as donors and recipients. We established an NL model by anastomosing the donor ascending aorta and pulmonary artery end-to-side to the recipient abdominal aorta and inferior vena cava, respectively, and ligating the superior and inferior vena cava on the donor right atrium. The method of the volume-loaded (VL) model was the same as described above, except we performed an anastomosis of the donor left atrium to the recipient abdominal aorta to allow volume loading of the donor's left ventricle. We assessed the characteristics of the grafts by the surgical success rate, echocardiography, and histologic evaluation between the two models. ResultsEchocardiography showed that donor left ventricle in VL models was volume loaded and had normal systolic and diastolic function compared with the NL models. The mean weight of NL hearts was significantly less than that of VL hearts. Morphologic observation revealed that thrombus formation in donor heart cavities in NL model was significantly higher than that in the VL model. The area of cardiomyocytes per high-power field in the NL model was significantly lower than that in the VL model. ConclusionsWe provide a novel VL heterotopic heart transplantation model in rats, in which hemodynamic performance of grafts is close to the normal cardiac physiologic situation; thus, the novel model will be more suitable for clinical research.

Bilateral Sequential Lung Transplantation

Bilateral Sequential Lung Transplantation

Multislice Computed Tomography Evaluation 21 Years After Heterotopic Heart Transplantation

A 47-year-old man was investigated in the heart transplantation unit of our hospital almost 21 years after he had undergone a heterotopic heart transplantation at the Harefield Hospital (England). This is probably the longest-living heterotopic heart transplantation patient ever. In June 1983, he received heart transplant for end-stage heart failure resulting from dilated cardiomyopathy. Nowadays, heterotopic heart transplantation is hardly performed but may be indicated when the patient has irreversible pulmonary hypertension or when the donor heart is believed to be too small to support the recipient’s circulation. This donor heart came from a 16-year-old boy, and a full heterotopic transplantation was performed with the donor pulmonary artery inserted into the recipient pulmonary artery. After a successful operation and some initial signs of rejection, this patient has been living a reasonably normal life. He was initially managed with triple-therapy immunosuppression; currently, he receives cyclosporine monotherapy. Since 1999, he has been known …

Sonolucent Space Posterior to Left Atrium: Unusual Echocardiographic Appearance in a Cardiac Transplant Patient

The usual echocardiographic appearances of the atria in heart transplant patients are well known. We report a case of an 81-year-old man with a 16-year-old cardiac transplant who showed a "new" echocardiographic left atrial abnormality. Two-dimensional echocardiography showed a large sonolucent space behind the donor left atrium (DLA), which was at first perplexing. This space, the distorted and partly displaced recipient left atrium (RLA), could be shown to communicate with the donor left atrium, by the use of unconventional imaging and by optison opacification.

Experimental heterotopic heart transplantation without cardiopulmonary bypass: auxiliary support for the recipient heart

Background: Auxiliary cardiac support using heterotopic heart transplant is of considerable interest, but the outcome is not known. To investigate technical feasibility and the possibility of using auxiliary support from heterotopic heart transplantation without cardiopulmonary bypass, we evaluated hemodynamics including the pressure–volume relationship in experimental animals. Methods In heterotopic heart transplantation, we tailored the donor heart by removing the pulmonary and tricuspid valves, and by wide removal of the inter-atrial septum. Next, we anastomosed the descending aorta and left atrium of the donor heart to the descending aorta and left atrium of the recipient, without using cardiopulmonary bypass. Consequently, declamping the recipient’s descending aorta allowed the donor heart to fill with blood and to start beating. We performed hemodynamic assessments including the effects of adrenergic stimulation. We measured the pressure and volume relationship of the recipient heart by closing and opening inflow of the donor left atrium to change the pre-load of the donor left ventricle. Results The donor left ventricle produced a systolic blood pressure that was augmented by the recipient blood pressure and responded to adrenergic stimulation. When inflow of the donor left atrium was opened, the pressure–volume loop of the recipient heart shifted to the left and pressure–volume area decreased. Simultaneously, the mechanical efficiency and E max (the slope of the end-systolic pressure-volume relationship) of the recipient heart increased when inflow of the donor left atrium was opened. Conclusions This transplant model, without cardiopulmonary bypass, is feasible and can be applied to transplant investigations as a working heart model on the basis of the response of adrenergic stimulation. The increased pre-load of the donor left atrium from the recipient left atrium resulted in a recipient leftward shift of the pressure–volume relationship, suggesting that this transplant model with adequate pre-load acts as auxiliary assistance in the recipient intrathoracic cavity.

Significance of positive cultures from donor left atrium and postpreservation fluid in heart transplantation.

The significance of positive perioperative cultures routinely obtained from the donor left atrium and postpreservation fluid during heart transplantation is unknown. A retrospective chart review of 128 heart transplant recipients was done. A total of 106 of 128 patients had left atrial and/or postpreservation fluid cultures performed; 61 (57.5%) of them were positive. Forty-one positive left atrial or postpreservation cultures grew indolent organisms and 20 grew virulent organisms. Six donors had positive blood cultures, and five of the six did not have left atrial or postpreservation fluid cultures positive for the same organism. Seven recipients had positive blood cultures with organisms different from their corresponding left atrial or postpreservation fluid cultures. Three patients had sternal wound infections with organisms different from their donors' left atrial or postpreservation fluid cultures. Seven patients received additional antibiotics after heart transplantation specifically directed at a positive left atrial or postpreservation fluid culture for 5 to 7 days; none of them developed infection with these organisms. We found no evidence that positive donor left atrium or postpreservation fluid cultures increase the recipients' risk of infection. Nevertheless, we cannot refute that the small group of patients who received additional antibiotics might have developed an infection if they had not been treated. We recommend that the left atrial and postpreservation fluid cultures growing indolent organisms be discounted. However, if they grow more virulent organisms, consideration could be given to a brief course of specific therapy while awaiting recipient cultures.

Pulmonary venous anastomosis in lung transplantation without donor left atrium: Experimental and clinical results

Single lung transplantation now is a therapeutic option for some patients with end-stage lung disease. Cyclosporine immunosuppression and refinements in bronchial anastomosis have been responsible for recent successes. Since 1953, the usual pulmonary venous anastomosis, both in experimental animals and in humans, has been an atrium-to-atrium connection. This technique may limit the availability of usable donor lungs, since the donor heart, along with the atrium, is usually harvested for another recipient. Although techniques can be developed to allow both transplant teams to harvest atrial tissue, this study was undertaken to determine if, in fact, anastomosis with donor left atrium is necessary. Twenty-four dogs were anesthetized and a left thoracotomy performed. After heparinization (3 mg/kg), the pulmonary artery and left atrium were occluded. One of four different pulmonary venous anastomoses was performed at 3.5x magnification: superior pulmonary vein end to end (group I), inferior pulmonary vein end to end (group II), superior pulmonary vein implantation into left atrium (group III), and left atrium-to-left atrium anastomosis as control (group IV). Everting mattress sutures of 7-0 polypropylene were used in groups I, II, and III and 6-0 in group IV. Average crossclamp time for group I, group II, and group IV was 20 minutes. The average crossclamp time for group III was 10 minutes. All anastomoses were patent at the time of 1-week reevaluation. Gross and microscopic examination demonstrated establishment of an intimal lining; organized nonocclusive thrombus was present in only one anastomosis. We conclude that atrium-to-atrium anastomosis is not necessary for a successful single lung transplantation, and that transplantation of a single lobe is feasible. The best alternative is implantation of the pulmonary vein into the left atrium, which will easily allow use of the heart and both lungs from a single donor to different recipients. We have used this anastomosis in one patient without difficulty.

A modification of the intrathoracic parallel heart transplant technique

A new technique of orthotopic transplantation of a heart in parallel with the recipient's heart is described. It involves four anastomoses (a) donor's left atrium to the recipient's left atrial cuff. (b) End-to-end donor's left pulmonary artery to the recipient's left pulmonary artery. (c) End-to-side aorta to aorta and (d) end-to-side superior vena cava to superior vena cava. Thus, each heart is connected to one lung. The advantages of the technique are pointed out.