Respiratory virus infections in transplant recipients after reduced-intensity conditioning with Campath-1H: high incidence but low mortality

Respiratory virus infections can cause serious morbidity and mortality after conventional allogeneic stem cell transplantation. However, the incidence and outcome of these infections after reduced intensity conditioning has not been reported. Between 1997 and 2001, 35 episodes of respiratory virus infections were noted in 25 of 83 transplant recipients conditioned with fludarabine, melphalan and Campath-1H, and 80% of them received early antiviral therapy. Parainfluenza virus (PIV) 3 was the commonest isolate (45.7%) followed by respiratory syncytial virus (37%). Patients with myeloma were more susceptible to these infections [odds ratio (OR) 4.1, P = 0.01] which were often recurrent in patients with severe acute or chronic graft-versus-host disease (GVHD) (OR 10.6, P = 0.03). Infection within the first 100 d (OR 5.0, P = 0.05) and PIV 3 (OR 9.2, P = 0.01) isolation were risk factors for developing lower respiratory infection. Although more than half of the episodes progressed to lower respiratory infection, the mortality was only 8%. This could have been due to early initiation of antiviral therapy, but the attenuation of pulmonary damage due to the reduced-intensity conditioning, low incidence of GVHD and, paradoxically, the low CD4+ T-cell subset in this setting might also have been contributory factors.     

Transcatheter Aortic Valve Implantation: Bahrain Experience

BACKGROUNDTranscatheter aortic valve implantation (TAVI) is a minimally invasive procedure that is considered a good alternative to surgical aortic valve replacement (sAVR) in selected patients. Our aim is to determine the baseline, procedural characteristics and one-year clinical outcomes of our TAVI registry.METHODSThis study is a retrospective observational analysis of a prospectively designed cohort comprising 81 consecutive patients treated at Mohammed bin Khalifa Cardiac Centre (MKCC) who were enrolled in Bahrain TAVI registry from February 2014 to February 2019. The clinical endpoints were defined according to the updated Valve Academic Research Consortium-2 (VARC-2) consensus document.RESULTSOut of the 81 patients included in our study, there were 37 (45.7%) males. The mean age was 76.4 ± 8.9 years with a mean Logistic European System for Cardiac Operative Risk Evaluation (EuroSCORE II) of 4.1 ± 2.5 and a mean Society of Thoracic Surgery (STS) Risk Score of 4.2 ± 3.5. Evolute-R valve was used for 36 (44.4%) patients, Edward Sapien for 26 patients (32.1%), and Core valve for 19 patients (23.5%). At one year follow up, all-cause death was reported in three (3.7%) patients; none of them was cardiovascular mortality. As per VARC-II criteria, no cases fulfilled the criteria of valve dysfunction but TAVI-related complications (i.e., TAV-in-TAV deployment) were reported in four (4.9%) cases. One (1.2%) case of major bleeding was encountered but no patient experienced life-threatening bleeding. Major vascular complications were documented in two patients (2.5%) only. Significant Acute Kidney Injury (AKI) occurred in two (2.5%) patients, both classified as stage-2 but no one deteriorated to stage-3 or hemodialysis. Seven (8.6%) patients required permanent pacemakers, and all were implanted during the index admission for TAVI. One patient (1.2%) had stroke and all survivors completed one-year follow up.CONCLUSIONThe TAVI program in Bahrain is encouraging and corresponds to the finest international centers outcomes in terms of procedural success and complications rate.     

Evaluation of HIV protease inhibitor use and the risk of sudden death or nonhemorrhagic stroke

Concerns have arisen about possible effects of protease inhibitors (PIs) on cardiac conductivity. We found no significant association between current or recent PI exposure and sudden death or nonhemorrhagic stroke (adjusted rate ratio, 1.22; 95% confidence interval, .95-1.57), whereas cumulative exposure to PIs was associated with an increased risk (adjusted rate ratio, 1.06 per year of exposure; 95% confidence interval, 1.01-1.11).     

Resveratrol inhibits neointimal formation after arterial injury through an endothelial nitric oxide synthase-dependent mechanism

Revascularization procedures used for treatment of atherosclerosis often result in restenosis. Resveratrol (RSV), an antioxidant with cardiovascular benefits, decreases neointimal formation after arterial injury by a mechanism that is still not fully clarified. Our main objective was to address the role of nitric oxide synthases (NOSes) and more specifically the endothelial-NOS (eNOS) isoform as a mediator of this effect. RSV (4 mg/kg/day, s.c.) alone or in combination with the NOS inhibitor N-nitro-L-arginine methyl ester (L-NAME) (2 mg/kg/day, s.c.) was given to Sprague-Dawley rats beginning at 3 days before arterial (carotid or aortic) injury. RSV reduced neointimal formation by 50% (P<0.01), decreased intimal cell proliferation by 37% (P<0.01) and reduced inflammatory markers such as PECAM and MMP-9 mRNA. These effects of RSV were all abolished by coadministration of l-NAME. Oral RSV (beginning at 5 days before arterial injury) reduced neointimal thickness after femoral wire injury in mice, however this effect was not observed in eNOS knockout mice. This is the first report of RSV decreasing neointimal cell proliferation and neointimal growth through an eNOS-dependent mechanism.     

Mitochondrial dysfunction in antiphospholipid syndrome: implications in the pathogenesis of the disease and effects of coenzyme Q(10) treatment

The exact mechanisms underlying the role of oxidative stress in the pathogenesis and the prothrombotic or proinflammatory status of antiphospholipid syndrome (APS) remain unknown. Here, we investigate the role of oxidative stress and mitochondrial dysfunction in the proatherothrombotic status of APS patients induced by IgG-antiphospholipid antibodies and the beneficial effects of supplementing cells with coenzyme Q(10) (CoQ(10)). A significant increase in relevant prothrombotic and inflammatory parameters in 43 APS patients was found compared with 38 healthy donors. Increased peroxide production, nuclear abundance of Nrf2, antioxidant enzymatic activity, decreased intracellular glutathione, and altered mitochondrial membrane potential were found in monocytes and neutrophils from APS patients. Accelerated atherosclerosis in APS patients was found associated with their inflammatory or oxidative status. CoQ(10) preincubation of healthy monocytes before IgG-antiphospholipid antibody treatment decreased oxidative stress, the percentage of cells with altered mitochondrial membrane potential, and the induced expression of tissue factor, VEGF, and Flt1. In addition, CoQ(10) significantly improved the ultrastructural preservation of mitochondria and prevented IgG-APS-induced fission mediated by Drp-1 and Fis-1 proteins. In conclusion, the oxidative perturbation in APS patient leukocytes, which is directly related to an inflammatory and pro-atherothrombotic status, relies on alterations in mitochondrial dynamics and metabolism that may be prevented, reverted, or both by treatment with CoQ(10).