Emergent TandemHeart-ECMO for acute severe mitral regurgitation with cardiogenic shock and hypoxaemia: a case series.

BACKGROUND: Acute severe mitral regurgitation (MR) associated with cardiogenic shock is a life-threatening emergency. Traditional teaching has focused on the need for emergent coronary angiography and/or intra-aortic balloon counterpulsation in preparation for emergent open-heart surgery for repair/replacement. Unfortunately, emergent open-heart surgery in patients with acute MR complicated by cardiogenic shock is associated with 25-46% perioperative mortality. New devices have provided additional options for stabilization prior to emergent surgery which facilitate improved outcomes. CASE SUMMARY: We present two cases of acute severe MR resulting in cardiogenic shock and profound hypoxaemia. TandemHeart® mechanical circulatory support with an oxygenator spliced into the circuit, akin to veno-arterial extracorporeal membrane oxygenation (ECMO), facilitated haemodynamic stabilization and decongestion of the lungs facilitating successful bridge to mitral valve surgery. Successful discharge to home was achieved in both patients with good neurological outcomes and sustained long-term functional recovery at 18 and 14 months, respectively. DISCUSSION: Selective use of the TandemHeart®, with or without ECMO, facilitates management of the critically ill cardiogenic shock patient with acute severe MR.

Post-transplant survival in idiopathic pulmonary fibrosis patients concurrently listed for single and double lung transplantation.

BACKGROUND: Lung transplantation is a widely accepted treatment for patients with end-stage lung disease related to idiopathic pulmonary fibrosis (IPF). However, there are conflicting data on whether double lung transplant (DLT) or single lung transplant (SLT) is the superior therapy in these patients. The purpose of this study was to determine whether actuarial post-transplant graft survival among IPF patients concurrently listed for DLT and SLT is greater for recipients undergoing the former or the latter. METHODS: The United Network for Organ Sharing provided de-identified patient-level data. Analysis included lung transplant candidates with IPF listed between January 1, 2001 and December 31, 2009 (n = 3,411). The study population included 1,001 (29.3%) lung transplant recipients concurrently listed for DLT and SLT, all ≥18 years of age. The primary outcome measure was actuarial post-transplant graft survival, expressed in years. RESULTS: Among the study population, 433 (43.26%) recipients underwent SLT and 568 (56.74%) recipients underwent DLT. The analysis included 2,722.5 years at risk, with median graft survival of 5.31 years. On univariate (p = 0.317) and multivariate (p = 0.415) regression analyses, there was no difference in graft survival between DLT and SLT. CONCLUSIONS: Among IPF recipients concurrently listed for DLT and SLT, there is no statistical difference in actuarial graft survival between recipients undergoing DLT vs SLT. This analysis suggests that increased use of SLT for IPF patients may increase the availability of organs to other candidates, and thus increase the net benefit of these organs, without measurably compromising outcomes.

Mixed group of Rhizobiales microbes in lung and blood of a patient with fatal pulmonary illness.

We examined the microbial composition in the diseased lung and early-phase microbial cultures from the blood of a patient with a rapidly progressing fatal pulmonary illness. Although no microbes could be isolated from such cultures during the initial study, the HTS-microbiome study revealed the presence of a unique mixture of alphaproteobacteria, composed mainly of different families of Rhizobiales microbes. Microbial 16S rDNA sequences matching closely to Afipia cberi were identified mainly in the patient's diseased lung tissue, but only rarely in the early-phase blood cultures. Conversely, the high abundance of sequences found in early-phase blood cultures of different broth media matched closely with those of the families Methylobacteriaceae, Phyllobacteriaceae and Sphingomonadaceae. The two species that successfully adapted to grow in a laboratory culture system were A. cberi and Mesorhizobium hominis, which eventually were isolated from a previously cryopreserved blood culture of SP4 broth. Many other species, including members of the Bradyrhizobiaceae and Phyllobacteriaceae families, and all members of the Methylobacteriaceae and Sphingomonadaceae families identified by HTS remained non-cultivated. We developed specific PCR primers and FISH probes, which detected the target Rhizobiales microbes in former blood cultures and autopsy lung tissues. It is unclear what role these Rhizobiales microbes might have played in the patient's complex disease process. However, the above mentioned assays should help in rapidly detecting and identifying these previously unrecognized Rhizobiales microbes in patients.

A prospective, randomized trial of single-drug versus dual-drug immunosuppression in heart transplantation: the tacrolimus in combination, tacrolimus alone compared (TICTAC) trial.

BACKGROUND: Cardiac transplantation, a procedure nearly abandoned in the 1970s, has evolved into the standard of care for appropriate patients with end-stage heart failure. Much of this success has been due to improvements in immunosuppression, including the introduction of a triple-drug regimen. Retrospective reports suggested that single-drug immunosuppression with tacrolimus was feasible. As such, a prospective, randomized trial was conducted to test this approach. METHODS AND RESULTS: One hundred fifty adult de novo heart transplant recipients were enrolled in a prospective, randomized, controlled, open-label trial comparing tacrolimus monotherapy (MONO) with tacrolimus and mycophenolate mofetil therapy (COMBO). Corticosteroids were used in the early postoperative period but discontinued in all patients over 8 to 9 weeks. The primary end point was the composite biopsy score at 6 months after transplant. Patients were followed for 1 to 5 years. The composite biopsy score was similar between groups at 6 and 12 months: 6-month MONO, 0.70 ± 0.44 (95% confidence interval, 0.60 to 0.80) versus COMBO, 0.65 ± 0.40 (95% confidence interval, 0.55 to 0.74; P=0.44). Allograft vasculopathy was assessed by angiography and intravascular ultrasound, with no significant differences noted. Three-year survival was also similar (92.4% MONO versus 97% COMBO; P=0.58, log-rank). CONCLUSIONS: Addition of mycophenolate to single-agent immunosuppression did not provide an advantage over single-agent immunosuppression in terms of rejection, allograft vasculopathy, or 3-year survival. Corticosteroids, which have traditionally been a mainstay of therapy, were successfully discontinued in all patients. These conclusions are tempered by the limited statistical power associated with a sample size of only 150 patients. Clinical Trial Registration- URL: http://www.clinicaltrials.gov. Unique identifier: NCT00299221.

Randomized trial of tacrolimus monotherapy: tacrolimus in combination, tacrolimus alone compared (the TICTAC trial).

BACKGROUND: Prior retrospective studies have suggested that tacrolimus monotherapy is an option associated with excellent outcomes and reduced toxicities. METHOD: We conducted a prospective, randomized, 2-center study of tacrolimus combination therapy vs monotherapy. From April 16, 2004, to September 15, 2005, 58 adult heart transplant patients were studied. All received oral tacrolimus, mycophenolate mofetil, and corticosteroids. Patients were then randomized to a group where mycophenolate was maintained (COMBO) or to a group where it was discontinued (MONO) 14 days post-transplant. Corticosteroids were rapidly withdrawn in both groups between 8 and 12 weeks. RESULT: The primary end point (mean 6-month International Society of Heart and Lung Transplantation biopsy score) was 0.44 +/- 0.04 in the MONO group and 0.60 +/- 0.05 in the COMBO group (p = 0.013, unpaired Student's t-test). The freedom from rejection grade of 2R or higher at 6 and 12 months was 93.3% with MONO and 92.9% with COMBO (p = NS). CONCLUSION: Tacrolimus monotherapy appears to be safe and efficacious in heart transplant recipients and is not associated with excess rejection in the first year post-transplant. Further studies of this approach are warranted.

A multicenter, prospective, randomized, double-blind trial of basiliximab in heart transplantation.

BACKGROUND: The role and pharmacokinetics of interleukin-2 (IL-2) monoclonal antibodies (mAbs) in heart transplantation remain unclear. This 1-year double-blind, randomized, placebo-controlled study evaluated safety, tolerability, and pharmacokinetics of the IL-2 mAb basiliximab with cyclosporine, mycophenolate mofetil, and steroids in adult de novo heart transplant recipients. METHODS: Fifty-six patients received either basiliximab (20 mg) or placebo on Days 0 and 4 post-transplantation. Safety assessments included adverse events, serious adverse events, and infections. The time to and severity of biopsy-proven acute rejection (BPAR) were also assessed. RESULTS: Basiliximab was generally well tolerated. There were no significant differences between treatment groups with respect to adverse event profiles, serious adverse events (84.0% vs 61.3%), or infections (84% vs 74.2%). The mean number of days to first BPAR was longer with basiliximab (73.7 +/- 59.68) than placebo (40.6 +/- 53.30) at 6 months, but not statistically significant (trend). The duration that basiliximab concentrations exceeded the CD25 saturation threshold averaged 38 +/- 13 days. Patients with rejection did not clear basiliximab faster or have shorter durations of saturation than rejection-free patients. None of the patients screened had detectable anti-idiotype antibodies. CONCLUSIONS: These pilot results describe the pharmacokinetics of basiliximab and show that basiliximab appears to be tolerated with a similar safety profile to placebo in adult de novo heart transplant recipients. Larger scale clinical trials are feasible and warranted.

Heart allograft rejection: detection with breath alkanes in low levels (the HARDBALL study).

BACKGROUND: We evaluated a new marker of heart transplant rejection, the breath methylated alkane contour (BMAC). Rejection is accompanied by oxidative stress that degrades membrane polyunsaturated fatty acids, evolving alkanes and methylalkanes, which are excreted in the breath as volatile organic compounds (VOCs). METHODS: Breath VOC samples (n = 1,061) were collected from 539 heart transplant recipients before scheduled endomyocardial biopsy. Breath VOCs were analyzed by gas chromatography and mass spectroscopy, and BMAC was derived from the abundance of C4-C20 alkanes and monomethylalkanes. The "gold standard" of rejection was the concordant set of International Society for Heart and Lung Transplantation (ISHLT) grades in biopsies read by 2 reviewers. RESULTS: Concordant biopsies were: Grade 0, 645 of 1,061 (60.8%); 1A, 197 (18.6%); 1B, 84 (7.9%); 2, 93 (8.8%); and 3A, 42 (4.0%). A combination of 9 VOCs in the BMAC identified Grade 3 rejection (sensitivity 78.6%, specificity 62.4%, cross-validated sensitivity 59.5%, cross-validated specificity 58.8%, positive predictive value 5.6%, negative predictive value 97.2%). Site pathologists identified the same cases with sensitivity of 42.4%, specificity 97.0%, positive predictive value 45.2% and negative predictive value 96.7%. CONCLUSIONS: A breath test for markers of oxidative stress was more sensitive and less specific for Grade 3 heart transplant rejection than a biopsy reading by a site pathologist, but the negative predictive values of the 2 tests were similar. A screening breath test could potentially identify transplant recipients at low risk of Grade 3 rejection and reduce the number of endomyocardial biopsies.