Atrial fibrillation following lung transplantation: double but not single lung transplant is associated with long-term freedom from paroxysmal atrial fibrillation.

INTRODUCTION: The cornerstone of catheter ablation for atrial fibrillation (AF) is pulmonary vein electrical isolation (PVI). Recurrent AF post-PVI is a major limitation of the procedure with PV reconnection present in most patients. Single (SLT) and double (DLT) lung transplant surgery involves a 'cut and sew' PV antral isolation analogous to a catheter-based approach providing an opportunity to assess the efficacy of durable PVI. METHODS AND RESULTS: A total of three hundred and twenty-seven consecutive lung transplant patients were compared with 201 control non-transplant thoracic surgery (THR) patients between 1998 and 2008. The primary analysis was the incidence of 'early' post-operative AF and 'late' AF (AF occurring following discharge from hospital after the index operation). Risk factors for the development of late AF were analysed using regression analysis. Acute post-operative AF was more common post-lung transplant (DLT 58/200 (29%) and SLT 36/127 (28%) vs. THR 28/201 (13.9%), P < 0.001) occurring at 4.7 ± 5.0 days in DLT, 3.4 ± 2.5 days after SLT, and 7.4 ± 11.2 days in the thoracic group (P < 0.001). At a mean follow-up of 5.4 ± 2.9 years late AF occurred in 1/200 (0.5%) in DLT vs. 16/127 (12.6%) in SLT and 23/201 (11.4%, P < 0.001) in THR groups. Kaplan-Meier survival analysis demonstrated the association of DLT with long-term freedom from AF. Significant variables [hazard ratio (HR) on univariate regression analysis fo late AF were: DLT 0.06, age 1.09, LA diameter 1.2, hypertension 3.0, preoperative AF 12.2, early AF 8.8, rejection 3.2]. CONCLUSION: Double but not SLT provides long-term freedom from AF despite a similar early post-operative incidence. This supports the critical role of the pulmonary veins in the pathogenesis of atrial fibrillation and the importance of durable electrical isolation of the pulmonary veins as the cornerstone in strategies for the long-term prevention of AF.

Pediatric experience with the VentrAssist LVAD.

PURPOSE: The purpose of this study is to describe the first experience of implanting a new left ventricular assist device in pediatric patients with end-stage heart failure. DESCRIPTION: In two recent prospective, international, multicenter clinical trials, three children (aged

Incidence of malignancies in heart and/or lung transplant recipients: a single-institution experience.

BACKGROUND: The purpose of this study was to determine the incidence and type of malignancies in heart and/or lung transplant recipients at a single institution in Victoria, Australia, and to compare these findings with the non-transplant general Victorian population. METHODS: Recipients of heart and/or lung transplants at the Alfred Hospital between February 1989 and January 2004 were cross-referenced with the Victorian Cancer Registry. The medical records of all patients with a cancer diagnosis by January 1, 2005 were reviewed. Data were collected on baseline demographics, including cancer type, stage, treatment and survival. Cancer incidence was then compared with rates found in the Victorian population. RESULTS: There were 907 transplants (Tx) conducted between February 1989 and January 1, 2004 on 905 patients, which included 424 heart (HTx), 56 heart-lung (HLTx), 200 single-lung (SLTx), and 227 double-lung (DLTx) procedures. Of these patients, 606 (67%) were male and 299 (33%) were female. Mean age at transplantation was 46.4 years (range 12.6 to 70.4 years). Four hundred twenty-four (47%) deaths have occurred. Median survival for all patients after transplantation was 8.6 years. One hundred two cancers were confirmed, translating to a 7.1-fold increased incidence compared with the non-transplant population. The most common cancer diagnoses were lymphoproliferative disorders (692 per 100,000 person-years), head and neck cancer (336 per 100,000 person-years) and lung cancer (251 per 100,000 person-years). Compared with the non-transplant population this translates into a 26.2-, 21.0- and 9.3-fold increased risk for developing these cancers, respectively, after cardio-pulmonary transplantation. CONCLUSIONS: Certain malignancies are more common after heart and/or lung transplantation. The most predominant in our cohort were lymphoproliferative disorders, head and neck cancer and lung cancer.

Fast-track cardiac surgery: application in an Australian setting.

In response to the current state of healthcare in Australia, our unit has employed a fast-track policy for low-risk cardiac surgery patients since January 2000. This study was designed to examine the safety and efficacy of this policy. From July 2001 to June 2004, 342 (23%) of 1,488 patients undergoing cardiac surgery were identified preoperatively as suitable for fast-track recovery. There was a significantly shorter median time to extubation (4 hr vs 9 hr), reduced intensive care unit stay (8 hr vs 26 hr), and a lower rate of readmission to the intensive care unit (0.6% vs 4.2%) for those fast tracked compared to the other patients. The fast-track group had a lower incidence of complications and significantly decreased median length of hospital stay (5 vs 7 days). We concluded that this policy accurately identifies the low-risk cardiac surgery patients suitable for less intensive postoperative recovery.

Evaluation of sympathetic re-innervation in heterotopic cardiac transplants by iodine-123-metaiodobenzylguanidine (I-123-MIBG) imaging.

Scintigraphy using iodine-123-metaiodobenzylguanidine (I-123-MIBG) has been used to demonstrate that >50% of orthotopically transplanted hearts undergo partial cardiac sympathetic re-innervation and that this occurs no earlier than 1 year post-transplant. This study used planar and singe-photon emission computed tomography (SPECT) I-123 MIBG scintigraphy to show that cardiac re-innervation was not detectable in any of the 8 patients studied 1.1 to 6.3 years post-heterotopic transplantation. Thus, potential for cardiac re-innervation varies according to the type of procedure performed.

Demonstrating time sequence and extent of sustained decrease in native heart ejection fraction after heterotopic transplantation.

BACKGROUND: In this study we investigate the time sequence and extent of the sustained decrease in native heart ejection fraction (EF) after heterotopic heart transplantation (HHTx) when using gated cardiac blood pool scanning (GCBPS) and transthoracic echocardiography (TTE) One case report of 2 patients used post-operative GCBPS and TTE and found a significant deterioration in native heart EF post-operatively over the course of several years. Comparison with pre-operative measurements using these techniques in a series of patients has not been performed previously. METHODS: Thirteen of 16 HHTx patients with adequate pre- and post-operative GCBPS follow-up were included in this study. All patients also underwent TTE post-operatively and the GCBPS results were correlated with the TTE findings. RESULTS: GCBPS demonstrated a marked (21.1 +/- 4.7% vs 10.5 +/- 3.7%, p < 0.0001) decrease in native EF post-HHTx. Spontaneous echo contrast in the native left ventricle and/or poor opening of the mitral/aortic valves was noted at Day 1 in 4 of 5 patients who had a TTE at this stage. No further decline was noted between the first and last post-operative GCBPS (10.8 +/- 3% vs 8.6 +/- 2.1%, p = NS). CONCLUSIONS: A dramatic decrease in native heart EF post-HHTx occurs as early as Day 1 post-transplant. Dissociation of ventricular contraction is the most likely cause. Studies have demonstrated that paced linkage (counterpulsation) between the ventricles results in improved hemodynamics. This may have clinical implications as to the timing of ejection of blood from a left ventricular assist device (LVAD) and for providing the best hemodynamics for the ventricle being assisted and for optimizing its chances of long-term recovery.

Sirolimus in de novo heart transplant recipients reduces acute rejection and prevents coronary artery disease at 2 years: a randomized clinical trial.

BACKGROUND: Sirolimus reduces acute rejection in renal transplant recipients and prevents vasculopathy in nonhuman primates and in-stent restenosis in humans. Its effects on rejection and transplant vasculopathy in human heart transplant recipients are unknown. METHODS AND RESULTS: In a randomized, open-label study, sirolimus was compared with azathioprine in combination with cyclosporine and steroids administered from the time of cardiac transplantation. We report 6-month rejection rates (primary end point), 12-month safety and efficacy data, and 6- and 24-month graft vasculopathy data in 136 cardiac allograft recipients randomly assigned (2:1) to sirolimus (n=92) or azathioprine (n=44). At 6 months, the proportion of patients with grade 3a or greater acute rejection was 32.4% for sirolimus 3 mg/d (P=0.027), 32.8% for sirolimus 5 mg/d (P=0.013), and 56.8% for azathioprine. Patient survival at 12 months was comparable among groups. Intracoronary ultrasound at 6 weeks, 6 months, and 2 years demonstrated highly significant progression of transplant vasculopathy in azathioprine-treated patients. At 6 months, a highly significant absence of progression in intimal plus medial proliferation and significant protection against luminal encroachment was evident in sirolimus-treated patients, and these effects were sustained at 2 years. CONCLUSIONS: Sirolimus use from the time of transplantation approximately halved the number of patients experiencing acute rejection. The measurable development of transplant vasculopathy at 6 months and 2 years in patients receiving azathioprine was not observed in patients receiving sirolimus.