Background: Heart failure (HF) is associated with excessive extracellular matrix (ECM) deposition and abnormal ECM degradation leading to cardiac fibrosis. Connective tissue growth factor (CTGF) modulates ECM production during inflammatory tissue injury, but available data on CTGF gene expression in failing human heart and its response to mechanical unloading are limited.Methods and Results: Left ventricle (LV) tissue from patients undergoing cardiac transplantation for ischemic (ICM; n = 20) and dilated (DCM; n = 20) cardiomyopathies and from nonfailing (NF; n = 20) donor hearts were examined. Paired samples (n = 15) from patients undergoing LV assist device (LVAD) implantation as "bridge to transplant" (34-1,145 days) also were analyzed. There was more interstitial fibrosis in both ICM and DCM compared with NF hearts. Hydroxyproline concentration was also significantly increased in DCM compared with NF samples. The expression of CTGF, transforming growth factor (TGF) beta 1, collagen (COL) 1-alpha 1, COL3-alpha 1, matrix metalloproteinase (MMP) 2, and MMP9 mRNA in ICM and DCM were also significantly elevated compared with NF samples. Although TGF-beta 1, CTGF, COL1-alpha 1, and COL3-alpha 1 mRNA levels were reduced by unloading, there was only a modest reduction in tissue fibrosis and no difference in protein-bound hydroxyproline concentration between pre- and post-LVAD tissue samples. The persistent fibrosis may be related to a concomitant reduction in MMP9 mRNA and protein levels following unloading.Conclusions: CTGF may be a key regulator of fibrosis during maladaptive remodeling and progression to HP. Although mechanical unloading normalizes most genotypic and functional abnormalities, its effect on ECM remodeling during HF is incomplete. (J Cardiac Fail 2013;19:283-294)

This study addresses how depletion of human cardiac left ventricle (LV) mitochondrial DNA (mtDNA) and epigenetic nuclear DNA methylation promote cardiac dysfunction in human dilated cardiomyopathy (DCM) through regulation of pyrimidine nucleotide kinases. Samples of DCM LV and right ventricle ( n = 18) were obtained fresh at heart transplant surgery. Parallel samples from nonfailing (NF) controls ( n = 12) were from donor hearts found unsuitable for clinical use. We analyzed abundance of mtDNA and nuclear DNA (nDNA) using qPCR. LV mtDNA was depleted in DCM (50%, P < 0.05 each) compared with NF. No detectable change in RV mtDNA abundance occurred. DNA methylation and gene expression were determined using microarray analysis (GEO accession number: GSE43435 ). Fifty-seven gene promoters exhibited DNA hypermethylation or hypomethylation in DCM LVs. Among those, cytosolic thymidine kinase 1 (TK1) was hypermethylated. Expression arrays revealed decreased abundance of the TK1 mRNA transcript with no change in transcripts for other relevant thymidine metabolism enzymes. Quantitative immunoblots confirmed decreased TK1 polypeptide steady state abundance. TK1 activity remained unchanged in DCM samples while mitochondrial thymidine kinase (TK2) activity was significantly reduced. Compensatory TK activity was found in cardiac myocytes in the DCM LV. Diminished TK2 activity is mechanistically important to reduced mtDNA abundance and identified in DCM LV samples here. Epigenetic and genetic changes result in changes in mtDNA and in nucleotide substrates for mtDNA replication and underpin energy starvation in DCM.

Atrial fibrillation (AF) and atrial flutter (AFL) after heart transplantation (HT) has been associated with increased mortality. Diverse incidence rates have been reported to date, with no clear classification according to the time of onset of such arrhythmias. We determined the incidence of AF/AFL using the time of onset after HT and analyzed the associated risk factors and outcomes. We performed a retrospective study of 228 HT recipients (March 1996 to July 2007), including donor and recipient demographics. gender mismatch, ischemia time, surgical anastomosis, time of onset of AF/AFL, acute cellular rejection, left ventricular systolic function, and all-cause mortality. The mean age of the donors (81% men) was 30 +/- 12 years and of the recipients (78% men) was 53 +/- 11 years. AF/AFL occurred in 45 patients (20%): 24(11%) in the first 30 days, 10(4%) within the 31 days to 1 year, and 11(5%) after 1 year. When the patients with AF/AFL were compared to those with sinus rhythm, the significant difference was the older mean age of the donors (p = 0.001) and the recipients (p = 0.02). The all-cause mortality rate was 43% for those with AF/AFL compared to 23% for those with sinus rhythm (hazard ratio 2.45; 95%' confidence interval 1.2 to 4.8), mostly driven by the greater mortality in the later-onset AF/AFL group (>30 days after HT). In conclusion, AF and AFL have an incidence of 20% after HT and are associated with increased overall mortality compared to that in patients in sinus rhythm. AF/AFL is more common within the first 30 days of HT, with an overall incidence of 20%. Older donor and recipient age is a risk factor associated with AF/AFL. Published by Elsevier Inc. (Am J Cardiol 2010;106:737-741)

Introduction Malignancy is a late cause of mortality in heart transplant recipients. It is unknown if screening computed tomography scan would lead to early detection of such malignancies or serious vascular anomalies post heart transplantation. Methods This is a single center observational study of patients undergoing surveillance computed tomography of chest, abdomen and pelvis atleast 5 years after transplantation. Abnormal findings, included pulmonary nodules, lymphadenopathy and intra-thoracic and intra-abdominal masses and vascular anomalies such as abdominal aortic aneurysm. The clinical follow up of each of these major abnormal findings is summarized. Results A total of 63 patients underwent computed tomography scan of chest, abdomen and pelvis at least 5 years after transplantation. Of these, 54 (86%) were male and 9 (14%) were female. Mean age was 52 ± 9.2 years. Computed tomography revealed 1 lung cancer (squamous cell) only. Non specific pulmonary nodules were seen in 6 patients (9.5%). The most common incidental finding was abdominal aortic aneurysms (N = 6 (9.5%)), which necessitated follow up computed tomography (N = 5) or surgery (N = 1). Mean time to detection of abdominal aortic aneurysms from transplantation was 14.6 ± 4.2 years. Mean age at the time of detection of abdominal aortic aneurysms was 74.5 ± 3.2 years. Conclusion Screening computed tomography scan in patients 5 years from transplantation revealed only one malignancy but lead to increased detection of abdominal aortic aneurysms. Thus the utility is low in terms of detection of malignancy. Based on this study we do not recommend routine computed tomography post heart transplantation.

Antibodies (ab) against human leukocyte antigens (HLA) in transplant (tx) recipients are associated with poor outcome. Flow PRA (panel reactive ab) detects non-specific ab against Class I & II HLA (%). New technology detects ab against donor HLA = Donor-Specific Ab (DSA). Experience with DSA in heart tx patients (pts) is limited. Purpose: To evaluate presence of non-specific ab & DSA and to correlate it with events in heart tx pts. Methods : We included all pts with heart tx done Feb 1986-Feb 2008 followed at our ctr with post-tx flow PRA drawn March 2006-Feb 2008 on random sample or event-related sample, ordered at clinician’s discretion. Random sample was drawn during clinic visit or hospital admission not related to graft rejection. Event is defined as hospital admission for suspected graft rejection. There were 277 samples drawn for flow PRA from 93 pts. To reduce bias related to multiple samples from 1 pt we included only 1 sample with highest PRA %. Pts were categorized in 2 groups: PRA ≥ 10% (high) and PRA < 10% (low). Low titer DSA was < 100,000 molecules of equivalent soluble fluorescence units (MESF). Results : Among 93 pts, 27 pts had PRA ≥10% (29%), among which 13 pts had event (14% of 93 pts) and 66 pts had PRA < 10% (71%) among which 3 pts had event (3% of 93 pts). Low PRA Group: Among 66 pts with PRA < 10%, 63 pts had no events (95.5%). Among 66 pts with PRA < 10%, 42 pts had no DSA tested and 24 pts had DSA tested. Among 24 pts with DSA tested, 23 pts had negative DSA and 1 pt had positive low titer DSA (this pt had no event). Three pts with negative DSA had an event; one of them had cross-reactive ab. High PRA Group: 27 pts with PRA≥10% were subcategorized in 2 groups based on the presence or the absence of the event. Group 1(N = 14 (52%)) had no event:8 pts did not have DSA drawn, 5 pts were DSA negative and 1 pt was positive with low titer DSA. Group 2(N = 13 (48%)) had an event:10 pts were DSA positive with high-titer, whereas 3 pts were DSA negative (1 pt had cross-reactive ab to donor-specific antigen). Difference between Groups 1 and 2 was significant by Fisher’s exact test (p < 0.05). Conclusions : Majority of pts hospitalized for suspected rejection (75%) had high-titer positive DSA (62.5%) or cross-reactive ab to donor-specific antigen (12.5%). This study will be basis for future prospective DSA monitoring.