Kidney transplantation in children weighing less than 15 kg: extraperitoneal surgical access-experience with 62 cases.

Small children are a challenging group in whom to perform KT. This retrospective study analyzed the results of 62 KTs in children weighing <15 kg, performed between 1998 and 2010, using extraperitoneal access and anastomosis of the renal vessels of donors to the aorta and IVC or iliac vessels of the recipients. Thirty-two (51.6%) grafts were LRDTs and 30 (48.4%) were DDRTs-28 of them pediatric. The mean age at KT was 3.7 ± 2.2 yr (1-12), and the mean weight was 12.3 ± 2.1 kg (5.6-14.9). Ten children weighed <10 kg, and five (8.1%) children presented previous thrombosis of the venous system. At one and five yr, patient survival was 93.2% and 84.2%, and graft survival was 85.2% and 72.7%. There were no differences between the rates for LRDT and DDRT. There were six vascular complications (four vascular thromboses, one laceration, and one renal artery stenosis) and two perirenal collections. Extraperitoneal access is a valid KT technique in children weighing <15 kg.

Results of en bloc renal transplants of pediatric deceased donors into adult recipients.

UNLABELLED: Various strategies have evolved to expand the donor pool due to the extreme shortage of organs. Herein we reviewed our experience with en bloc pediatric kidney transplantation since 1998. METHODS: From January 1998 to December 2004, nine adult patients underwent kidney transplantation using en bloc kidneys from donors <5 years old (range, 1 to 4). The mean age of the recipients was 45.1 years (range, 34 to 57). RESULTS: In recipients of en bloc pediatric transplantation, cold ischemia time ranged from 14 to 26.2 hours (mean, 21.3 hours). Mean serum creatinine at 3, 6, and 12 months after transplantation was 1.53 +/- 0.57, 1.27 +/- 0.27, and 1.15 +/- 0.26 mg/dL compared with 1.93 +/- 1.35, 1.81 +/- 1.17, and 1.73 +/- 0.85 (P = .08) in recipients of single kidneys from ideal cadaveric donors (UNOS criteria, n = 368). Patient and graft survival at 1 year were 88.8% compared with 91.2% and 85% with ideal donors (P = NS), respectively. Three cases required additional surgery. There was one death due to a cerebral vascular accident. CONCLUSION: The present study confirmed the excellent results achieved with transplantation using en bloc kidneys from young donors.

Factors predicting intermediate endpoints of cervical cancer and exposure to human papillomavirus (HPV) infections in young women screened as potential targets for prophylactic HPV vaccination in south of Brazil.

OBJECTIVE: To explore the predictors of intermediate endpoints of cervical cancer in 500 women living in Porto Alegre. STUDY DESIGN: Five hundred randomly selected women (mean age 20.3 years, range 15-25) were screened using PCR detecting 25 HPV types (HPV6, 11, 16, 18, 31, 33, 34, 35, 39, 40, 42, 43, 44, 45, 51, 52, 53, 54, 56, 58, 59, 66, 68, 70, and 74). Women were interviewed and serum samples were analysed for antibodies to HPV16 and HPV18 VLPs. Regression models were constructed to analyse predictive factors for (a) HPV PCR status, (b) HPV16-seropositivity, (c) HPV18-seropositivity, and (d) SIL in the PAP smear, used as intermediate endpoints of cervical cancer. RESULTS: Specific HPV types were identified in 137 (27.4%) of the 157 (31.4%) PCR-positive women. PAP test result was the most powerful independent predictor of HPV status in PCR (p = 0.0001), followed by the sexual activity started (p = 0.001) (adjusted OR 34.075, 95% CI: 4.650-249.715). PAP test SIL was independently predicted only by the HPV PCR status (p = 0.0001) (OR 7.561, 95% CI: 2.787-20.514). HPV16 and HPV18 serostatus were the most significant predictors of each other (p=0.0001), and the life-time number of sexual partners was more significant (p=0.001) predictor of HPV16 than HPV18 serostatus (p = 0.049). CONCLUSION: These data are useful in evaluating the exposure status of the women to the risk factors of cervical cancer in south of Brazil.

Influence of leptin, androgens and insulin sensitivity on increased GH response to clonidine in lean patients with polycystic ovary syndrome.

Our aim was to investigate whether insulin sensitivity, leptin, androgen or estradiol levels are associated with disturbed GH response to clonidine in lean patients with polycystic ovary syndrome. Fourteen lean polycystic ovary syndrome patients, 11 ovulatory patients presenting idiopathic hirsutism and 10 non-hirsute, normal women with regular cycles paired for age and BMI were included in a cross-sectional study. Baseline hormonal and metabolic variables were assessed and analyzed in association with GH response to oral administration of 0.3 mg of clonidine. Delta GH was significantly higher in the PCOS group than in the IH and control groups (p = 0.014). The groups were similar in terms of body mass index, insulin, glucose, total and HDL cholesterol, triglycerides and estradiol levels. Free androgen index (r = 0. 454, p = 0.015) and leptin (r = 0.419, p = 0.023) were positively correlated with the homeostasis model assessment. The homeostasis model assessment was the only variable that significantly correlated with GH response to clonidine (r = 0.375, p = 0.029) (vs. estradiol, free androgen index, leptin and LH). Nonetheless, when the analysis was adjusted for leptin levels and free androgen index, the statistical significance of this correlation was lost. The increased GH secretion observed in our lean PCOS patients may be associated with slight changes in insulin sensitivity, even in the absence of clinical evidence of insulin resistance. This association seems to be modulated by leptin and androgen levels.

Immunosuppression in pancreas transplantation: mycophenolate mofetil versus sirolimus.

The use of mycophenolate mofetil (MMF) in pancreas transplantation has increased graft survival and decreased the incidence of acute rejections episodes (ARE), regardless of the choice of calcineurin inhibitor. The combination of MMF with tacrolimus (TAC) is the most common protocol, it is considered the gold standard for new protocols. In the last few years, there have been reports of a small number of patients treated with sirolimus (RAPA), usually combined with TAC. Patient and pancreas survival rates as well as the incidence of ARE were similar to protocols with TAC and MMF. Twenty simultaneous pancreas and kidney (SPK) transplantations were performed using an immunosuppressive protocol of TAC, RAPA, and steroids (STE) after 2000. The incidence of ARE was 25%; all episodes responded to STE. Only 2 patients (10%) displayed hypercholesterolemia requiring treatment with statins. The use of RAPA as an alternative to MMF is promising, although presently one with limited experience. The combination of MMF and RAPA with or without a calcineurin inhibitor is an option to be evaluated in the future.

Transthoracic epicardial catheter ablation to treat recurrent ventricular tachycardia.

Nonsurgical epicardial transthoracic catheter ablation is a minimally invasive procedure that has proven to be efficacious for the treatment of ventricular tachycardia (VT). The usefulness of this technique depends on the prevalence of epicardial circuits, which seem more frequent in Chagasic than post-myocardial infarction VT. This approach is limited by concern regarding the potential adverse effects of radiofrequency (RF) ablation on the coronary arteries. However, the effects of RF ablation delivered in the vicinity of a major coronary artery are limited to the medial artery. Severe intimal hyperplasia and intravascular thrombosis may occur only when RF ablation is delivered above the artery. Moreover, susceptibility to damage is inversely proportional to the vessel size. Coronary artery injury is an uncommon (< 1%) complication that could be prevented by a coronary angiogram prior to ablation. Hemopericardium, another predictable complication occurring in 10% of patients, can be easily controlled in the electrophysiology laboratory.

Avaliaçäo da reduçäo de gradientes pressóricos e da hipertrofia ventricular após valvoplastia cirúrgica na estenose aórtica / Left ventricular hypertrophy regression immediately after aortic valve repair

INTRODUÇÇO: A correçäo cirúrgica da estenose aórtica resulta em reduçäo significativa do gradiente pressórico transvalvar, sendo acompanhada por regressäo da hipertrofia ventricular esquerda(HVE). A intensidade e a rapidez dessa regressäo tem sido objeto de avaliaçöes. A associaçäo de valvoplastia aórtica e regressäo imediata da HVE é relatada em poucos estudos. MÉTODOS: Foram estudados, prospectivamente, 11 pacientes submetidos à valvoplastia em estenose aórtica, utilizando-se ecocardiografia imediatamente antes da cirurgia e no período pós-operatório precoce (6,1 + ou - 0,9 dias). RESULTADOS: A espessura septal variou de 12,10 + ou - 1,66mm para 11,36 + ou - 1,12mm (reduçäo de 6,1 por cento) (NS) enquanto a espessura parietal variou 4,4 por cento (de 11,70 + ou - 1,41 mm para 11,18 + ou - 1,16mm) (NS). A fraçäo de ejeçöo apresentou uma variaçäo de 62,02 + ou - 18,59 por cento para 62,50 + ou - 11,74 por cento (NS). A massa ventricular esquerda variou em 6,7 por cento ( de 277,65 + ou - 114,80 g passou para 258,93 + ou - 92,38 g) (NS). O gradiente transvalvular médio regrediu de 53,6 + ou -10,3 mmHg para 23,0 + ou - 9,1mmHg, ou seja, 57 por cento (p<0.001). CONCLUSÕES: A valvoplastia alivia o gradiente pressórico aórtico satisfatoriamente e a regressäo da HVE tende a se iniciar logo após, porém ainda näo é significativa no período pós-operatório imediato

Nonsurgical transthoracic epicardial catheter ablation to treat recurrent ventricular tachycardia occurring late after myocardial infarction.

OBJECTIVES: We sought to evaluate feasibility, safety and results of transthoracic epicardial catheter ablation in patients with ventricular tachycardia occurring late after an inferior wall myocardial infarction. BACKGROUND: Transthoracic epicardial catheter ablation effectively controls recurrent ventricular tachycardia (VT) in patients with Chagas' disease in whom epicardial circuits predominate. Epicardial circuits also occur in postinfarction VT. METHODS: Fourteen consecutive patients aged 53.6 +/- 14.5 years with postinfarction VT related to the inferior wall were studied. The VT cycle length was 412 +/- 51 ms. Two patients had previously undergone unsuccessful standard endocardial radiofrequency energy (RF) ablation. The VT was incessant in one patient. Left ventricular angiography showed inferior akinesia in 13 patients and an inferior aneurysm in 1 patient. Ablation was performed with a regular steerable catheter placed into the pericardial sac by pericardial puncture. RESULTS: The pericardial space was reached in all patients. Electrophysiologic evidence of an epicardial circuit was present in 7 of 30 VTs. Due to a high stimulation threshold, empirical thermal mapping was the only criterion used to select the site for ablation. Three VTs were interrupted during the first RF pulse. Two pulses were necessary to render it noninducible in 3 patients (1 VT per patient). In the remaining 4 VTs, 3, 3, 4 and 5 RF pulses, respectively, were used. The overall success was 37.14% (95% confidence interval, 11.83% to 62.45%). Patients are asymptomatic for 14 +/- 2 months. CONCLUSIONS: Postinfarction pericardial adherence does not preclude epicardial mapping and ablation to control VT related to an epicardial circuit in postinferior wall myocardial infarction.

Nonsurgical transthoracic mapping and ablation in a child with incessant ventricular tachycardia.

We report the case of an 11-month-old child with incessant ventricular tachycardia who underwent two unsuccessful endocardial ablations with standard catheters and in whom the ventricular tachycardia was interrupted only during transthoracic epicardial catheter ablation. This report outlines the usefulness and safety of this novel approach in pediatric patients before surgery when endocardial ablation fails.

[Reduction of pressure gradients and of ventricular hypertrophy after surgical valvoplasty in aortic stenosis]. / Avaliação da redução de gradientes pressóricos e da hipertrofia ventricular após valvoplastia cirúrgica na estenose aórtica.

BACKGROUND: Relief of gradient is followed by myocardial mass reduction in aortic stenosis. Its degree and speed are under evaluation. Aortic valve repair in calcified aortic stenosis is less well studied than replacement. METHODS: We evaluated left ventricular hypertrophy reduction by echocardiogram in 11 patients immediately after valve repair in aortic stenosis at a mean of 6.1 +/- 0.9 days post operative. RESULTS: Septal width was 12.10 +/- 1.66 mm pre and 11.36 +/- 1.12 mm post operative, 6,1% reduction (NS). Parietal width varied 4.4% from 11.70+/-1.41 mm to 11.18 +/- 1,16 mm (NS). Ejection fraction went from 62.02+/-18.59% to 62.50+/-11. 74% (NS). Left ventricular mass varied 6.7%, from 277.65+/-114.80g to 258.93+/- 92.38 g (NS). Mean transvalvar gradient reduced 57%, from 53.56+/-10.30 to 23.0+/-9.1 mmHg (P<0.001). CONCLUSION: Aortic valve repair reduces gradients adequately and left ventricular hypertrophy shows a trend to regression soon after aortic repair, but is not yet significant in the first post-operatively week.

Probability of occurrence of life-threatening ventricular arrhythmias in Chagas' disease versus non-Chagas' disease.

The implantable cardioverter defibrillator (ICD) is highly effective in the treatment of ventricular arrhythmias (VA) responsible for sudden cardiac death. However, the probability of occurrence of these arrhythmic events in presence of cardiomyopathy remains uncertain. The aim of this study was to compare the probability of nonoccurrence of life-threatening VA in ICD recipients with Chagas' versus non-Chagas' heart disease. Over a mean follow-up of 10.5 months, 53 ICD recipients (mean age = 50.1 years, 48 male) were evaluated. Eleven patients had Chagas' heart disease, 19 had idiopathic dilated cardiomyopathy and 23 had ischemic cardiomyopathy. Ventricular tachyarrhythmias with a cycle length < 315 ms were considered life-threatening. The cumulative probability of nonoccurrence of life-threatening VA was examined by Kaplan-Meyer method and the outcomes were submitted to the log rank test. At 2 years, the cumulative probability of life-threatening VA nonoccurrence was 0 in the Chagas' heart disease group versus 40% up to 55 months of follow-up in the non-Chagas' disease group (P = 0.0097). Among patients with cardiomyopathies of different etiologies, those with Chagas' heart disease had the lowest cumulative probability of nonoccurrence of life-threatening VA, confirming its unfavorable prognosis and the importance of preventive measures against sudden death in this disease.

Predictive factors for persistence of atrial fibrillation after mitral valve operation.

BACKGROUND: The majority of patients operated on for mitral valve disease with chronic atrial fibrillation (AF) do not recover sinus rhythm with conventional postoperative treatment. The maze procedure may be used in these circumstances. To define the precise indications for the maze procedure, it would be necessary to identify those patients based on preoperative factors. METHODS: A retrospective study was undertaken on 100 consecutive patients operated on for mitral valve disease in chronic AF. The return to sinus rhythm was analyzed with relation to age, gender, AF duration, left atrial size, left ventricular ejection fraction, lesion type, valve procedure, associated procedures, and reoperation. RESULTS: At late follow-up (more than 1 year) 26 (26%) patients presented sinus rhythm and 74 (74%) remained in AF. Statistical single parametric analysis demonstrated that mitral stenosis was a risk factor for maintaining AF, whereas regurgitation was more associated to sinus rhythm recovery. There was no relation with the other parameters with return to sinus rhythm. It should be noted, however, that 96% of this series had AF for more than 6 months preoperatively. CONCLUSIONS: The majority of patients with mitral valve disease remain in AF and this may justify the association of maze procedure. Pure regurgitation may be a single predictor for return to sinus rhythm after mitral valve operation in chronic AF.

Radiofrequency catheter ablation of ventricular tachycardia guided by nonsurgical epicardial mapping in chronic Chagasic heart disease.

We report a case of a 63-year-old women with Chagas' disease and recurrent, syncopal VT treated by RF catheter ablation in whom endocardial application of RF energy was guided by nonsurgical epicardial mapping. The procedure was undertaken in the electrophysiology laboratory under deep anesthesia. VT was interrupted after 2.4 seconds of application and rendered noninducible afterwards. Two weeks after the procedure, a distinct morphology VT was induced by programmed ventricular stimulation, and the patient was started on amiodarone, remaining asymptomatic 12 months after the procedure.

Long-term results of visually guided left ventricular reconstruction as single therapy to treat ventricular tachycardia associated with postinfarction anteroseptal aneurysm.

INTRODUCTION: Postinfarction ventricular tachycardia (VT), anteroseptal aneurysm, and ventricular dysfunction are commonly associated and predict a poor long-term prognosis. Surgical left ventricular reconstruction, which includes double plication of the anterior and septal wall, can improve ventricular function. This article analyzes the long-term efficacy of such a procedure to control recurrence of VT in a group of 50 consecutive patients. METHODS AND RESULTS: The study group consisted of 50 consecutive patients operated on between December 1986 and December 1994. The group comprised 44 men and 6 women. The mean age was 56+/-11 years. All patients had spontaneous VT following an anterior myocardial infarction. Twenty-five patients had two or more episodes of VT (eight presented as cardiac arrest, nine as syncope). Coronary artery disease was limited to the left anterior descending artery in 27 patients. An anteroseptal aneurysm was present in 49 patients. All patients had VT induced by programmed ventricular stimulation before surgery, and left ventricular reconstruction was performed without intraoperative mapping in all cases. Total mortality, VT recurrence, and sudden death rate were the endpoints of the study. In-hospital mortality was 8%. Postoperative left ventricular ejection fraction improved from 0.38 to 0.50 (P<0.05). Only two patients had postoperative inducible VT. Overall survival, VT recurrence rate, and sudden death rate were 73%, 12%, and 10%, respectively, after a median follow-up period of 6.25 years (0 to 8 years). CONCLUSION: Visually guided left ventricular reconstruction with septal and anterior wall plicature can be utilized effectively to treat recurrent VT associated with postinfarction anteroseptal aneurysm.

[Relationship between conduction persistence through the slow pathway after atrioventricular nodal reentry tachycardia radiofrequency ablation and its recurrence]. / Relação entre a persistência da condução pela via lenta nodal após ablação de taquicardia por reentrada nodal e a recorrência clínica.

PURPOSE: The aim of this study is to verify whether the persistence of conduction over the slow pathway is related to an increased trend for recurrence. METHODS: Recurrence rate was retrospectively analyzed in 126 patients who underwent slow pathway radiofrequency (RF) catheter ablation during a follow-up of 20 +/- 12 months. The ablative procedure was interrupted when AVNRT was no longer induced by atrial stimulation after intravenous infusion of isoproterenol. Ninety-eight patients had no evidence of slow pathway whereas 28 patients persisted with AV node jump and atrial echo beat. RESULTS: There were 15 recurrences: 9% of those who had no evidence of slow pathway (9 of 98 patients) and 21% of those with AV node jump and/or atrial echo beat but this difference was not statistically significant. CONCLUSION: As long as AVNRT cannot be induced by atrial pacing and isoproterenol infusion after slow pathway RF catheter ablation, the presence of AV node jump and/or atrial echo beat does not increase the risk of recurrence of AVNRT.

Endocardial and epicardial ablation guided by nonsurgical transthoracic epicardial mapping to treat recurrent ventricular tachycardia.

INTRODUCTION: An epicardial site of origin of ventricular tachycardia (VT) may explain unsuccessful endocardial radiofrequency (RF) catheter ablation. A new technique to map the epicardial surface of the heart through pericardial puncture was presented recently and opened the possibility of using epicardial mapping to guide endocardial ablation or epicardial catheter ablation. We report the efficacy and safety of these two approaches to treat 10 consecutive patients with VT and Chagas' disease. METHODS AND RESULTS: Epicardial mapping was carried out with a regular steerable catheter introduced into the pericardial space. An epicardial circuit was found in 14 of 18 mapable VTs induced in 10 patients. Epicardial mapping was used to guide endocardial ablation in 4 patients and epicardial ablation in 6. The epicardial earliest activation site occurred 107+/-60 msec earlier than the onset of the QRS complex. At the epicardial site used to guide endocardial ablation, earliest activation occurred 75+/-55 msec before the QRS complex. Epicardial mid-diastolic potentials and/or continuous electrical activity were seen in 7 patients. After 4.8+/-2.9 seconds of epicardial RF applications, VT was rendered noninducible. Hemopericardium requiring drainage occurred in 1 patient; 3 others developed pericardial friction without hemopericardium. Patients remain asymptomatic 5 to 9 months after the procedure. Interruption during endocardial pulses occurred after 20.2+/-14 seconds (P = 0.004), but VT was always reinducible and the patients experienced a poor outcome. CONCLUSION: Epicardial mapping does not enhance the effectiveness of endocardial pulses of RF. Epicardial applications of RF energy can safely and effectively treat patients with VT and Chagas' disease.

Reduction of radiation exposure time during catheter ablation with the use of pulsed fluoroscopy.

UNLABELLED: Prolonged exposure to radiation during radiofrequency catheter ablation implies a potential risk of radiodermatitis, neoplasm and genetic defects to the patient and to the operator-physician. The use of pulsed fluoroscopy is thought to reduce such a risk because the radiation dose decreases for the same period of time. The aim of the present study was to compare the radiation exposure time during pulse and continuous radiofrequency catheter ablation. METHODS: Procedures were divided according to the sort of fluoroscopy utilized and the last four cases of atrioventricular (AV) junction ablation, four of atrial flutter, five of atrial tachycardia, 16 of AV node reentrant tachycardia, 16 of AV tachycardia and 10 of ventricular tachycardia in which pulsed and continuous fluoroscopy were utilized were respectively separated into Group I (pulse fluoroscopy) and Group II (continuous fluoroscopy) with 55 patients in each group. Fluoroscopy was generated by the same device in the two groups. Continuous fluoroscopy used 2 mA and automatic kV adjustment (automatic brightness stabilizer) ranging from 70 to 110 kV. Pulsed fluoroscopy was set at 7 squares/s with 25 mA and automatic kV adjustment. Fluoroscopy time was registered by the fluoroscopy device counter. RESULTS: Procedure duration, success rate and complications did not differ between Groups I and II. Fluoroscopy time, however, was 4.4+/-4 min during pulsed fluoroscopy and 27+/-23 min during continuous fluoroscopy (p=0.001). CONCLUSION: During radiofrequency catheter ablation procedures, the use of pulsed fluoroscopy set at 7 squares/s, decreases the radiation exposure time by 80% as compared to continuous fluoroscopy without changing procedure duration and success rate.