Regionalization of ST-segment elevation acute coronary syndromes care: putting a national policy in proper perspective.

A uniform policy for regionalization of ST-segment elevation myocardial infarction (STEMI) care raises several concerns. Transferring all STEMI patients to obtain primary percutaneous coronary intervention (PCI) may be less effective than transferring only high-risk STEMI patients. Delays in time to treatment >60 min associated with transferring patients for primary PCI may result in increased mortality for the average patient as compared with providing immediate fibrinolytic therapy at their initial hospital; yet more than 95% of patients transferred for primary PCI in the U.S. exceed this 60-min benchmark. Superior outcomes associated with treatment at higher-volume regional STEMI centers are inconsistent among centers, and there is no direct evidence that patients will benefit by a transfer to a high-volume hospital from a low-volume hospital. Published data suggest as many as 800 PCI patients would need to be transferred to a high-volume PCI hospital to avoid a single death at a low-volume PCI hospital. Although European randomized trial data suggest transferring patients with STEMI for primary PCI may be superior to immediate fibrinolytic therapy, these findings are unlikely to generalize to the U.S. health care system given size, geography, and organization. ST segment elevation myocardial infarction care regionalization would require a massive redistribution of health care resources, depriving several hospitals of advanced cardiac care facilities, expertise, and associated revenue. Clearer evidence of the benefits and discussion of potential harms are needed before adopting a national STEMI regionalization policy.     

Identification and characterization of aquaporin-2 water channel mutations causing nephrogenic diabetes insipidus with partial vasopressin response

Congenital nephrogenic diabetes insipidus (NDI) is a rare disease caused most often by mutations in the vasopressin V2 receptor (AVPR2). We studied a family which included a female patient with NDI with symptoms dating from infancy. The patient responded to large doses of desmopressin (dDAVP) which decreased urine volume from 10 to 4 I/day. Neither the parents nor the three sisters were polyuric. The patient was found to be a compound heterozygote for two novel recessive point mutations in the aquaporin-2 (AQP2) gene: L22V in exon 1 and C181W in exon 3. Residue Cys181 in AQP2 is the site for inhibition of water permeation by mercurial compounds and is located near to the NPA motif conserved in all aquaporins. Osmotic water permeability (Pf) in Xenopus oocytes injected with cRNA encoding C181W-AQP2 was not increased over water control, while expression of L22V cRNA increased the Pf to approximately 60% of that for wild-type AQP2. Co-injection of the mutant cRNAs with the wild-type cRNA did not affect the function of the wild-type AQP2. Immunolocalization of AQP2-transfected CHO cells showed that the C181W mutant had an endoplasmic reticulum-like intracellular distribution, whereas L22V and wild-type AQP2 showed endosome and plasma membrane staining. Water permeability assays showed a high Pf in cells expressing wild-type and L22V AQP2. This study indicates that AQP2 mutations can confer partially responsive NDI.      

ATG16L1 and NOD2 polymorphisms enhance phagocytosis in monocytes of Crohn’s disease patients

AIM:To investigate if the presence of relevant genetic polymorphisms has effect on the effectual clearance of bacteria by monocytes and granulocytes in patients with Crohn’s disease(CD).METHODS:In this study,we assessed the differential responses in phagocytosis by measuring the phagocytic activity and the percentage of active phagocytic monocytes and granulocytes in inflammatory bowel disease patients as well as healthy controls.As both autophagy related like 1(ATG16L1)and immunityrelated guanosine triphosphatase gene are autophagy genes associated with CD and more recently nucleo-tide-binding ligomerization domain-containing protein2(NOD2)has been identified as a potent inducer of autophagy we genotyped the patients for these variants and correlated this to the phagocytic reaction.The genotyping was done with restriction fragment length polymorphisms analysis and the phagocytosis was determined with the pHrodo?Escherichia coli Bioparticles Phagocytosis kit for flowcytometry.RESULTS:In this study,we demonstrate that analysis of the monocyte and granulocyte populations of patients with CD and ulcerative colitis showed a comparable phagocytic activity(ratio of mean fluorescence intensity)between the patient groups and the healthy controls.CD patients show a significantly higher phagocytic capacity(ratio mean percentage of phagocytic cells)compared to healthy controls(51.91%±2.85%vs 37.67%±7.06%,P=0.05).The extend of disease was not of influence.However,variants of ATG16L1(WT:2.03±0.19 vs homozygoot variant:4.38±0.37,P<0.009)as well as NOD2(C-ins)(heterozygous variant:42.08±2.94 vs homozygous variant:75.58±4.34(P=0.05)are associated with the phagocytic activity in patients with CD.CONCLUSION:Monocytes of CD patients show enhanced phagocytosis associated with the presence of ATG16L1 and NOD2 variants.This could be part of the pathophysiological mechanism resulting in the disease.     

Systems of care for ST-elevation myocardial infarction in India

The prevalence of coronary artery disease and ST-elevation myocardial infarction (STEMI) are increasing in India. Although recent publications have focused on improving preventive measures in developing countries, less attention has been placed on the acute management of STEMI. Recent policy changes in India have provided new opportunities to address existing barriers but require greater investment and support in the coming years.     

Safety and Effectiveness of Drug-Eluting Versus Bare-Metal Stents in Saphenous Vein Bypass Graft Percutaneous Coronary Interventions : Insights From the Veterans Affairs CART Program

Background

Stenosis of saphenous vein grafts (SVGs) after coronary artery bypass grafting (CABG) is common and often requires percutaneous coronary interventions (PCI) for treatment. However, data for the effectiveness of drug-eluting stents (DES) versus bare-metal stents (BMS) in SVG-PCI are unclear.

Objectives

This study sought to examine the association between DES versus BMS used during SVG PCI and clinical outcomes in the national Veterans Affairs integrated healthcare system.

Methods

We studied a national cohort of 2,471 post-CABG veterans undergoing SVG-PCI between 2008 and 2011 at all Veterans Affairs hospitals and compared clinical outcomes of between those receiving DES and BMS. Clinical outcomes included procedural complications, myocardial infarction (MI), and all-cause mortality. Comparisons were made in a propensity-matched cohort using Cox proportional hazards regression models.

Results

DES were used in 1,549 SVG-PCI patients (63%) and the use of DES increased progressively with each calendar year (50% in 2008 to 69% in 2011). Incidence of procedural complications was low and comparable in both groups (2.8% among BMS vs. 2.3% among DES patients; p = 0.54). During long-term (>2 years) follow-up, use of DES was associated with lower mortality than BMS (hazard ratio [HR]: 0.72; 95% confidence interval [CI]: 0.57 to 0.89) and similar rates of MI (HR: 0.94; 95% CI: 0.71 to 1.24) in the propensity-matched cohort.

Conclusions

In a national cohort of veterans, we observed widespread and increasing use of DES during SVG-PCI. In long-term follow-up, compared with BMS, DES use was safe and effective in SVG-PCI patients.