Scapulohumeral subluxation and luxation in five alpacas.

INTRODUCTION: The patient histories, findings from clinical examinations, diagnostic imaging techniques, the surgical procedures, complications, necropsy findings and the outcomes from five male or castrated male alpacas with scapulohumeral sub-/luxation are presented. These alpacas each had a history of severe forelimb lameness for one week (n: 1), four weeks (n: 2) and for two-to-three months (n: 2). Two of the five alpacas were euthanized due to severe osteoarthritic changes that developed during the two-to-three months of scapulohumeral luxation. Three alpacas were treated with open reduction and internal stabilisation by placing tension band sutures between one 4,5 mm cortical screw anchored in the scapular neck and two 4,5 mm cortical screws anchored in the greater humeral tubercle, all of them provided with washers. Post-surgery a carpal flexion sling was applied to avoid postoperative weight-bearing. An exercise programme was started after removal of the carpal sling and continued for 12 weeks. In one of the three alpacas an additional non-displaced fracture of the acromion occurred two weeks after surgery. In conclusion, all three treated alpacas had good-to-excellent long-term outcomes and are still alive 123, 15 and 12 months after surgical repair of the scapulohumeral sub-/luxation. As four weeks, or even up to three months elapsed in four of these five alpacas until a definitive diagnosis was made, more education should be provided to alpaca owners that severely lame animals should be presented to a veterinarian with adequate diagnostic possibilities and expertise as soon as possible in order not to compromise treatment success.

INTRODUCTION: Dans cette étude rétrospective, on présente les antécédents des patients, les résultats des examens cliniques, les techniques d'imagerie diagnostique, les procédures chirurgicales, les complications, les résultats de l'autopsie et les résultats finaux de cinq alpagas mâles ou mâles castrés souffrant d'une subluxation ou luxation scapulo-humérale. Ces alpagas présentaient chacun des antécédents de boiterie sévère des membres antérieurs depuis une semaine (n: 1), quatre semaines (n: 2) et deux à trois mois (n: 2). Deux des cinq alpagas ont été euthanasiés en raison des changements arthrosiques graves qui s'étaient développés au cours des deux à trois mois de luxation scapulo-humérale. Trois alpagas ont été traités par réduction ouverte et stabilisation interne en plaçant des sutures à bande de tension entre une vis corticale de 4,5 mm ancrée dans le col de l'omoplate et deux vis corticales de 4,5 mm ancrées dans le tubercule huméral supérieur, toutes munies de rondelles. Après l'opération, une écharpe de flexion du carpe a été mise en place pour éviter la mise en charge postopératoire. Un programme d'exercices a été mis en place après le retrait de l'écharpe carpienne et a été poursuivi pendant 12 semaines. Chez l'un des trois alpagas, une fracture non déplacée de l'acromion s'est produite deux semaines après l'opération. En conclusion, les trois alpagas traités ont eu des résultats à long terme bons à excellents et sont toujours en vie 123, 15 et 12 mois après la réparation chirurgicale de la subluxation scapulo-humérale. Dans la mesure où il s'est écoulé quatre semaines voire jusqu'à trois mois chez quatre de ces cinq alpagas avant qu'un diagnostic définitif ne soit posé, il convient d'informer davantage les propriétaires d'alpagas que les animaux gravement boiteux doivent être présentés à un vétérinaire disposant des possibilités de diagnostic et de l'expertise adéquates le plus rapidement possible afin de ne pas compromettre le succès du traitement.

Ultrasonographic diagnosis of closed pedal bone fractures in bovine claws: An ex-vivo study in slaughterhouse specimens.

Pedal bone fractures are one of the most common fracture locations in adult cattle and can be diagnosed by radiographs in two planes. Most bovine practitioners do not have access to such X-ray machines, but many use ultrasound units on a daily basis, primarily for reproductive medicine. For this reason, in this double-masked, randomized controlled study, we aimed to investigate the suitability of ultrasonographic examination using a 5 MHz linear transducer for diagnosing closed fractures of the pedal bone in cattle. A total of 54 hindlimb claws from slaughtered cattle were prepared and approximately 50% of the claws were artificially fractured. All claws were ultrasonographically examined twice by two examiners to determine the presence or absence of fractures and their locations. Ultrasound results were confirmed using radiographs of the claws as the reference standard method. All fracture locations as determined by ultrasonography were situated within ±2 mm of the radiographically-determined fracture zone. Ultrasound examination yielded a calculated sensitivity of 93%, a specificity of 91% and an inter-rater reliability of 0.77. The intra-rater reliability for the examiners were 0.96 and 0.88. Examiner experience with ultrasound examination and using ultrasound images for diagnosis could have influenced diagnostic accuracy. We conclude that artificially-created pedal bone fractures in ex-vivo bovine claws can be diagnosed using ultrasonography; similar results are expected in live animals. These results should encourage veterinarians to use ultrasonography for diagnosing pedal bone fractures in cattle.

Replacement of the aortic root in patients with Marfan's syndrome.

BACKGROUND: Replacement of the aortic root with a prosthetic graft and valve in patients with Marfan's syndrome may prevent premature death from rupture of an aneurysm or aortic dissection. We reviewed the results of this surgical procedure at 10 experienced surgical centers. METHODS: A total of 675 patients with Marfan's syndrome underwent replacement of the aortic root. Survival and morbidity-free survival curves were calculated, and risk factors were determined from a multivariable regression analysis. RESULTS: The 30-day mortality rate was 1.5 percent among the 455 patients who underwent elective repair, 2.6 percent among the 117 patients who underwent urgent repair (within 7 days after a surgical consultation), and 11.7 percent among the 103 patients who underwent emergency repair (within 24 hours after a surgical consultation). Of the 675 patients, 202 (30 percent) had aortic dissection involving the ascending aorta. Forty-six percent of the 158 adult patients with aortic dissection and a documented aortic diameter had an aneurysm with a diameter of 6.5 cm or less. There were 114 late deaths (more than 30 days after surgery); dissection or rupture of the residual aorta (22 patients) and arrhythmia (21 patients) were the principal causes of late death. The risk of death was greatest within the first 60 days after surgery, then rapidly decreased to a constant level by the end of the first year. CONCLUSIONS: Elective aortic-root replacement has a low operative mortality. In contrast, emergency repair, usually for acute aortic dissection, is associated with a much higher early mortality. Because nearly half the adult patients with aortic dissection had an aortic-root diameter of 6.5 cm or less at the time of operation, it may be prudent to undertake prophylactic repair of aortic aneurysms in patients with Marfan's syndrome when the diameter of the aorta is well below that size.

Fenestration of extracardiac fontan and reversal of protein-losing enteropathy: case report.

We describe a patient with protein-losing enteropathy who presented 6 months after undergoing a modified Fontan operation. After failing to respond to medical therapy, the Fontan tunnel was fenestrated by catheter intervention with immediate improvement and resolution of hypoproteinemia and enteric protein loss.

Clinical markers in CSF for determining neurologic deficits after thoracoabdominal aortic aneurysm repairs.

BACKGROUND: Spinal cord ischemia is a major cause of morbidity and mortality after thoracoabdominal aortic aneurysm operations. The incidence of paraplegia is high even in experienced institutions. METHODS: We investigated whether neurotransmitter excitotoxicity is associated with neurologic deficits after thoracoabdominal aortic aneurysm operations. We hypothesized that patients with spinal cord injury would manifest elevated levels of excitatory amino acids in their cerebrospinal fluid. Sixteen patients undergoing thoracoabdominal aortic aneurysm operations had cerebrospinal fluid drawn through lumbar spinal drains preoperatively, intraoperatively, and postoperatively. Excitatory amino acid levels (glutamate, aspartate, glycine) were measured using high-performance liquid chromatography. Excitatory amino acid levels were compared in patients who exhibited no neurologic deficits postoperatively (group I; n = 12) with patients who had clinically evident lower extremity and cerebral neurologic deficits (group II; n = 4). RESULTS: Significant elevations in glutamate and aspartate levels from baseline (p < 0.05) were limited to group II. Excitatory amino acid levels in group II were significantly elevated (p < 0.05) compared with those observed in group I. Glutamate levels were especially increased during aortic cross-clamping and late reperfusion, whereas aspartate levels were increased only during late reperfusion. CONCLUSIONS: These data suggest that neurotransmitter excitotoxicity plays a significant role in central nervous system injury.

Cardiac operations in children with Marfan's syndrome: indications and results.

BACKGROUND: The development of new screening techniques for the early detection of Marfan's syndrome has prompted evaluation of the results of cardiac operations in children with this syndrome. The purpose of this study was to determine the surgical indications, operative results, and need for reoperation in children with Marfan's syndrome. METHODS: From 1980 to 1996, 245 patients underwent cardiac operations for complications of Marfan's syndrome; 26 (11%) were less than 18 years of age. The mean age at the time of operation was 10.3 +/- 1 years (range, 8 months to 17 years); 18 of the patients were male. Indications for operation were aortic root dilatation (15 patients), mitral regurgitation (4 patients), aortic root dilatation and mitral regurgitation (6 patients), and aortic arch aneurysm (1 patient). Operations included aortic root replacement (15 patients), aortic root replacement and mitral repair (5 patients), aortic root replacement and mitral replacement (1 patient), mitral repair (3 patients), mitral replacement (1 patient), and arch aneurysm repair (1 patient). The mean aortic root diameter in patients undergoing aortic root replacement was 6.2 +/- 0.2 cm. Only 1 patient underwent ascending aortic dissection. RESULTS. There were no operative deaths. At a mean follow-up of 67.1 +/- 10.2 months, 8 patients required a second cardiac procedure (41% +/- 17% 10-year freedom from reoperation). Indications for further operations were distal aortic pathology (3 patients), aortic root dilatation after initial mitral operation (3 patients), failed mitral repair (1 patient), and homograft degeneration (1 patient). Risk factors for a second cardiac procedure were age less than 10 years at the time of the first operation (p < 0.003) and mitral regurgitation (p < 0.04). Overall, 25 (96%) of 26 patients have undergone aortic root replacement and 11 (42%) patients have undergone a mitral procedure. There have been 4 late deaths, all of presumed cardiac origin. The 10-year survival rate is 79% +/- 10%. All surviving patients are in New York Heart Association functional class I or II. CONCLUSIONS: We conclude that (1) aortic root dilatation is the most common surgical indication in children with Marfan's syndrome, (2) mitral regurgitation is the second most common indication, (3) aortic dissection is unusual in children with Marfan's syndrome, and (4) careful follow-up is necessary, particularly in younger children, because more than half of all children with Marfan's syndrome require repeated cardiac operations within 10 years.

Immunohistochemical abnormalities of fibrillin in cardiovascular tissues in Marfan's syndrome.

BACKGROUND: Molecular defects in the glycoprotein fibrillin are believed to be responsible for impaired structural integrity of cardiovascular, skeletal, and ocular tissues in Marfan's syndrome (MFS). Traditionally, excellent results have been achieved with the Bentall composite graft repair of aneurysms of the ascending aorta in MFS. However, because of the potential complications associated with prosthetic valves, there is growing interest in techniques that preserve the native aortic valve. METHODS: Between May 1994 and February 1995, 15 patients with a history of concomitant or remote aortic root aneurysms or dissection underwent operation for valvular heart disease. Specimens of aortic valve, ascending aortic wall, and mitral valve were obtained specifically to observe differences in fibrillin content and architecture between patients with (n = 9) and without (n = 6) MFS. In addition, control specimens of aortic valve, aortic wall, and mitral valve were obtained from 4 patients with isolated valvular or coronary artery disease but no evidence of connective tissue disorders or other aortic pathologic conditions. Fibrillin immunostaining using indirect immunofluorescence was used. Specimens were coded and graded by a blinded observer to determine quantity, homogeneity, and fragmentation of fibrillin. RESULTS: Observed fibrillin abnormalities in MFS and control patients were limited to the midportion (elastin-associated microfibrils) of the aortic valve, aortic wall, and mitral valve tissues. Fibrillin abnormalities of aortic valve, aortic wall, and mitral valve tissues were seen in all patients with MFS and were most severe in those older than 20 years. Similar fibrillin abnormalities of aortic valve and aortic wall specimens were observed in control patients more than 60 years old. CONCLUSIONS: Even in the setting of a normal-appearing aortic valve, the current rationale for widespread use of valve-sparing repairs of aortic root aneurysms in patients with MFS and patients older than 60 years should be carefully reexamined in light of these findings.

Intermediate results of the extracardiac Fontan procedure.

BACKGROUND: Fourteen children (ages 2 to 14 years) and 1 adult (32 years) have undergone a modification of the Fontan procedure in which an extracardiac lateral tunnel or conduit is used in combination with staged or simultaneous bidirectional Glenn shunt(s). METHODS: Extracardiac lateral tunnels (n = 9) were constructed using a polytetrafluoroethylene patch (n = 7), pericardial patch (n = 1), or in situ pericardial flap (n = 1). Extracardiac lateral conduits (n = 6) were constructed using nonvalved homografts (n = 2) or polytetrafluoroethylene tube grafts (n = 4). Fenestrations were created in 4 patients (2 each in extracardiac lateral tunnel and extracardiac lateral conduit patients). Aortic cross-clamping was completely avoided in 12/15 patients (aortic cross-clamping in 2 patients for atrial septal defect enlargement and 1 for Damus-Kaye-Stansel procedure). RESULTS: There have been no operative deaths. Prolonged postoperative chest tube drainage (> 2 weeks) has been rare (n = 1). At follow-up (range, 6 to 54 months; mean, 27.5 months), all patients are in New York Heart Association class I or II and remain in normal sinus rhythm. Late protein-losing enteropathy was seen in 1 patient and was successfully treated by percutaneous creation of a stented fenestration from the extracardiac tunnel to the systemic atrium. Late catheterizations reveal unobstructed extracardiac lateral tunnel function and low pulmonary pressures (range, 11 to 13 mm Hg). Advantages of the extracardiac Fontan include (1) avoidance of aortic cross-clamping in most patients, (2) the hemodynamic benefits of total cavopulmonary connection, (3) avoidance of atriotomy and intraatrial suture lines, (4) preservation of sinus rhythm and no arrhythmias at 2 year follow-up, (5) drainage of the coronary sinus to low pressure atrium, (6) allowance for early/late fenestrations, (7) prevention of baffle leaks and intraatrial obstruction, and (8) allowance for growth (tunnel procedures only). CONCLUSIONS: We recommend this extracardiac procedure for all suitable patients undergoing surgical conversion to the Fontan circulation.

Bioprosthetic versus mechanical prostheses for aortic valve replacement in the elderly.

BACKGROUND: Many centers advocate bioprosthetic valves in the elderly to avoid anticoagulation, in particular when patient survival is less than the expected valve durability. Because expected survival in the elderly is increasing and age-specific risk of anticoagulation in the elderly is not known, we examined valve- and anticoagulation-related morbidity in elderly patients after aortic valve replacement (AVR) with bioprostheses or mechanical prostheses. METHODS AND RESULTS: Between January 1980 and June 1994, 211 patients age > or = 70 years underwent isolated AVR; there were 109 men (52%) and 102 women (48%). Mean age was 75.9 +/- 4.8 years. Aortic stenosis was present in 194 (92%) patients. Bioprostheses were used in 145 (69%) and mechanical prostheses were used in 66 (31%). Chronic anticoagulation was maintained in all patients with a mechanical valve and in 18 patients (12%) with a bioprosthetic valve. Follow-up data were obtained for 98% (194 of 197) of hospital survivors at a mean follow-up of 3.8 years. Operative mortality was 6.6%; survival at 3 and 5 years was 75.3 +/- 3% and 64.6 +/- 4%, respectively. There was no significant difference in operative or late mortality between patient groups. Rates of freedom from thromboembolic events, endocarditis and anticoagulant-related hemorrhage for bioprosthetic and mechanical valve patients were similar. Prosthetic failure was identified in three bioprosthetic valves (2%); furthermore, the 4 patients in the series who required reoperation had received bioprostheses at the first operation. CONCLUSIONS: In conclusion, (1) elderly patients undergoing isolated AVR can be managed with either mechanical or bioprosthetic valves with similar early and late risk, as long as there are no specific contraindications to anticoagulation; (2) anticoagulation-related risk of hemorrhage is low in this group of elderly patients; and (3) the low but significant risk of reoperation following the use of bioprostheses suggests that mechanical valves may be underused in the elderly.

The Marfan syndrome and the cardiovascular surgeon.

The authors present the current status of surgery for the cardiovascular manifestations of the Marfan syndrome. In addition, a brief review of current Marfan genetic research is presented. Data on all Marfan patients undergoing aortic root replacement at the Johns Hopkins Hospital (September 1976-June 1995) were analyzed. Survival and event-free curves were calculated and risk factors for early and late death were determined by univariate and multivariate analysis. Two hundred twelve Marfan patients underwent aortic root replacement using composite graft (202), homograft (8) or valve-sparing procedures (2). One hundred eighty-five patients underwent elective repair with no 30-day mortality. Twenty-seven patients underwent urgent surgery, primarily for acute dissection; two patients with aortic rupture died in the operating room. Actuarial survival of the 212 patients was 88% at 5 years, 78% at 10 years and 71% at 14 years. By multivariate analysis, only poor NYHA class, male gender and urgent surgery emerged as significant independent predictors of early or late mortality. Histologic examination of excised Marfan aortic leaflets by immunofluorescent staining for fibrillin showed fragmentation of elastin-associated microfibrils. These studies suggest cautious use of valve-sparing procedures in Marfan patients. Over the last 5 years significant progress has been made in identifying mutant genes that code for defective fibrillin microfibrils in Marfan patients. Attempts are underway to develop animal models of Marfan disease for study of possible gene therapy. Aortic root replacement can be performed in Marfan patients with operative risk under 5%. Long-term results are gratifying. At present, valve-sparing procedures should be used cautiously in Marfan patients because of fibrillin abnormalities in the preserved aortic valve leaflets.

Neurologic injury in cardiac surgical patients with a history of stroke.

BACKGROUND: Controversy still exists as to whether patients with previous stroke are at increased risk for neurologic complications after heart operations. METHODS: We performed a prospective analysis of 1,000 consecutive patients undergoing cardiac operations requiring cardiopulmonary bypass, without hypothermic circulatory arrest. Of the 1,000 patients, 71 had previously documented stroke (study group); 2 control patients with no history of stroke were selected for each of these patients (control group, n = 142). There were no significant differences between the study and control patients with respect to established risk factors for neurologic complications. RESULTS: Compared with controls, study patients took longer to awaken (12.6 +/- 10.9 versus 3.5 +/- 2.1 hours; p < 0.0001) and longer to extubate (29.5 +/- 29.3 versus 9.1 +/- 5.2 hours; p < 0.001), and had a greater incidence of reintubation (7 of 71, 9.9% versus 2 of 142, 1.4%; p < 0.01) and postoperative confusion (26 of 71, 36.6% versus 7 of 142, 4.9%; p < 0.001). There was a higher incidence of focal neurologic deficit among study patients (31 of 71, 43.7% versus 2 of 142, 1.4%; p < 0.001). These deficits included new stroke (6 of 71, 8.5%) as well as the reappearance of previous deficits (19 of 71, 26.8%) or worsening of previous deficits (6 of 71, 8.5%), without new abnormalities on head computed tomography or magnetic resonance imaging. Study patients with neurologic deficit had longer cardiopulmonary bypass times than did study patients without deficit (146 +/- 48.5 versus 110 +/- 43.3 minutes; p < 0.001). The 30-day mortality rate was greater in study patients than in controls (5 of 71, 7% versus 1 of 142, 0.7%; p < 0.02), with four deaths among the 6 study patients with a new stroke (66.7%). CONCLUSION: This analysis identifies a group of patients at high risk for neurologic sequelae and confirms the vulnerability of the previously injured brain to cardiopulmonary bypass, as evidenced by reappearance or exacerbation of focal deficits in such patients.

Aortic dissection in a cardiac allograft recipient: a case report.

Ascending aortic dissection is rare in cardiac allograft recipients. Only two patients with dissection arising from the native aorta have been reported previously and, unfortunately, the diagnosis was made postmortem in each instance. We report the first case of successful surgical treatment of aortic dissection confined to the donor aorta in a recipient of an orthotopic cardiac allograft.

The extracardiac total cavopulmonary connection for definitive conversion to the Fontan circulation: summary of early experience and results.

Between July 1991 and March 1993, five children (ages 2 to 6 years) with complex congenital heart disease have undergone a new operation for conversion to the Fontan circulation. This procedure combines a bidirectional Glenn shunt with an extracardiac lateral tunnel (ELT) to carry systemic venous return to the pulmonary arteries (PAs). The ELT was constructed so that the circumference consists of Gore-Tex (2/3) and lateral epicardial atrial wall (1/3). The ELT can be performed with all varieties of single ventricle physiology, as in our patients with tricuspid atresia (n = 3), dextrocardia (n = 1), and situs inversus with levocardia (n = 1). PA reconstruction was required in four patients. At follow-up from 1 to 20 months, all patients are in New York Heart Association Class I and in normal sinus rhythm. Postoperative catheterization has revealed low PA pressures (< or = 12 +/- 1 mmHg) and angiography has shown excellent ELT function with brisk flow into the PAs bilaterally. All patients maintain an O2 saturation > 94% on room air. The advantages of this new extracardiac modification of Fontan's operation are: (1) aortic cross-clamping is not usually required; (2) incorporation of lateral atrial wall in ELT allows for growth while permitting construction of a fenestration or adjustable atrial septal defect in high risk patients; (3) absence of atriotomy and intraatrial suture lines may decrease late risk of arrhythmias; (4) early or late baffle leaks cannot occur; (5) intraatrial obstruction from the baffle cannot occur; (6) coronary sinus remains in low pressure atrium; and (7) hydrodynamic benefits of the total cavopulmonary connection are preserved. We recommend this procedure for patients undergoing surgical conversion to the Fontan circulation.

Extracardiac total cavopulmonary connection.

We report the case of a 6-year-old child who underwent definitive conversion to the Fontan circulation using a newly conceived operative technique. This new procedure allows the operation to be performed as a totally extracardiac operation and is based on the hydrodynamic principles of the total cavopulmonary connection.

Pediatric thoracic trauma.

The majority of chest injuries in children may be effectively diagnosed and treated in the emergency room area, if an organized plan is followed and a high index of suspicion for specific injuries is maintained. Unique features of pediatric anatomy and physiology require innovative adaptation to provide maximal effective resuscitation. Children in this sense are not merely "little adults." Of those few blunt and penetrating injuries that require operative management, operative techniques do not differ from those employed in adult trauma patients.

Evaluation of congenital heart disease by three-dimensional magnetic resonance imaging.

This study was undertaken to compare electrocardiographically gated magnetic resonance imaging (MRI) to established imaging modalities in the detection of complex intra- and extracardiac morphologic defects. Twenty-three patients with congenital cardiac abnormalities were imaged by four methods: cardiac catheterization, echocardiography, two-dimensional (2D) transaxial MRI, and three-dimensional (3D) MRI surface reconstruction. Observers with experience in congenital cardiac disease diagnosis (two for echo, one for catheterization, two for 2D MR, and three for 3D MR) evaluated the images in a blinded fashion, and the results were analyzed with receiver operating characteristic (ROC) analysis. Overall, cardiac catheterization had the best diagnostic performance. The diagnostic value of routine 2D cardiac MR images and 3D MR reconstruction images were similar to that of echocardiography. All of the modalities performed poorly in the diagnosis of extracardiac defects and atrial septal defects.

Three-dimensional magnetic resonance imaging.

Three-dimensional surface reconstruction images of the heart and great vessels can be produced from contiguous sequences of ECG-triggered MR scans in patients with congenital heart disease. The methods allow separation of the epi- and endocardial surfaces and definition of the enclosed blood volumes on a slice-by-slice basis. Surface reconstruction images have value in communicating the results of MR examinations to clinicians in cases where cardiac morphology is unusually complex; in depicting intracardiac defects, size, and location; and in aiding the study of pulmonary venous drainage. This method can be practical in studying cardiac morphologic abnormalities and especially in planning cardiac surgery.

[Design, efficiency and application of experimental methods in heart transplantation]. / Diseños, rendimientos y aplicaciones de técnicas experimentales en el trasplante cardíaco.

Heart transplantation in children with end-stage heart disease or severe congenital heart defect with uncertain surgical palliation, like the hypoplastic left heart syndrome, has become an accepted form of therapy in certain selected Medical Centers. Increasing number of heart transplantation in children have resulted from increased survival attributable to the introduction of cyclosporine. Nevertheless, the diagnosis of rejection in infants and children remains controversial being a great challenge derived by the need for repetitive and routine heart biopsies. Taking in mind that a non-invasive electrophysiologic method could be considered a promising method for monitoring heart allograft rejection the present study was begun. A total of 306 heart transplantation was performed, 206 heterotopic on rats and 30 orthotopic on dogs. Non-invasive monitoring of heart rejection was made by electrophysiologic techniques using an epicardial lead implanted on the donor heart. R wave and slew-rate measurements were performed daily at 30', primero, segundo, tercero quinto and séptimo day postransplant. These measurements were later compared to histopathologic studies. R wave and slew-rate values of alogenic or rejecting hearts were found to decrease significantly as compared to singenic or non-rejecting heart along the days. This non-invasive electrophysiologic method may be considered a promising and suitable method for monitoring heart allograft rejection.