Impact of Acute Coronary Syndrome Classification and Procedural Technique on Clinical Outcomes in Patients With Coronary Bifurcation Lesions Treated With Drug‐Eluting Stents

Background:

We examined the impact of non–ST‐segment elevation acute coronary syndrome (NSTE‐ACS) on clinical outcomes in patients with bifurcation lesions treated with drug‐eluting stents.

Hypothesis:

We hypothesized that NSTE‐ACS would be attributable to the increased risk of major adverse cardiac events (MACE) in bifurcation percutaneous coronary intervention.

Methods:

We enrolled 1668 patients, using data from a multicenter real‐world bifurcation registry. The primary objective was to compare the 2‐year cumulative risk of MACE in patients with NSTE‐ACS to those with stable angina. Major adverse cardiac events were defined as the composite endpoint of cardiac death, myocardial infarction (MI), and target‐lesion revascularization.

Results:

Non–ST‐segment elevation acute coronary syndrome was seen in 969 (58.1%) patients and stable angina in 699. Major adverse cardiac events occurred in 7.3% of NSTE‐ACS patients and in 5.2% with stable angina (P = 0.042). However, cardiac death, MI, and target‐lesion revascularization were similar between the 2 groups. We stratified patients with NSTE‐ACS into those with non–ST‐segment elevation MI and those with unstable angina. Cumulative risks of 2‐year MACEs were 7.0% in non–ST‐segment elevation MI patients and 7.5% in unstable angina patients (P = 0.87). In the NSTE‐ACS cohort, the baseline lesion length in the side branch (adjusted hazard ratio [HR]: 1.04, 95% confidence interval [CI]: 1.01‐1.07, P = 0.022), paclitaxel‐eluting stents in the main vessel (adjusted HR: 2.02, 95% CI: 1.21‐3.40, P = 0.008), and final kissing ballooning (adjusted HR: 1.88, 95% CI: 1.10‐3.21, P = 0.021) were independent predictors of MACE.

Conclusions:

Compared with stable angina patients, the NSTE‐ACS patients who underwent bifurcation percutaneous coronary intervention had an increased risk of MACE during the 2‐year follow‐up. Clin. Cardiol. 2012 doi: 10.1002/clc.22020 Drs Pil Sang Song and Dong Ryeol Ryu contributed equally to this work. Coronary Bifurcation Stenting (COBIS) Registry in South Korea, US Department of Health and Human Services, US National Institutes of Health, ClinicalTrials.gov no. NCT00851526. This work was supported by the Korean Society of Interventional Cardiology, Seoul, South Korea. The authors have no other funding, financial relationships, or conflicts of interest to disclose.     

Single-strand conformation polymorphism analysis is a rapid and effective method for the identification of mutations and polymorphisms in the gene for glycoprotein IIIa

Glanzmann thrombasthenia (GT) is the most common inherited disorder of platelets. Most of the molecular defects previously identified in GT have been caused by point (or other small) mutations in the genes for glycoprotein (GP) IIb or GPIIIa. We have used single-strand conformation polymorphism (SSCP) analysis to rapidly identify single- base changes in the GPIIIa gene. Using genomic DNA from normal individuals and patients with GT, each GPIIIa exon and a short stretch of flanking intronic sequence was amplified, heat-denatured, and separated in nondenaturing acrylamide gels. Only those fragments with an abnormal migration pattern were isolated and the nucleotide sequence determined. Using SSCP, we detected the polymorphism in the HPA-1 (P1A) system and all three known silent polymorphisms in the GPIIIa gene. Screening 14 GPIIIa exons from 5 patients with GT, one mutant allele was identified. The nucleotide sequence of the abnormal 240-bp SSCP fragment was determined and a G-->A substitution in the splice donor site of exon iv was identified. Analysis of platelet RNA resulting from this mutation showed two mRNA species: one contained a deletion of exon iv, whereas the other had a 27-bp addition to exon iv due to the use of a cryptic splice site in the downstream intron. Single-base substitutions are the most common mutation in GT and often result in abnormal mRNA splicing. SSCP is a rapid and sensitive technique for identifying mutations or polymorphisms in the GPIIIa gene.     

Budd‐Chiari syndrome in Sweden: epidemiology,clinical characteristics and survival – an 18‐year experience

Background: The exact incidence and prevalence of Budd‐Chiari syndrome (BCS) is unknown in the general population. Published reports differ in terms of the clinical characteristics, effects of therapy and survival. Aims: To investigate the epidemiology, clinical presentation and survival in patients with BCS. Methods: Retrospective multicentre study in Sweden reviewing the medical records of all patients with BCS 1986–2003, identified from the computerised diagnosis database of 11 hospitals, including all university hospitals and liver transplantation centres. Results: Forty‐three patients with BCS were identified, of whom nine (21%) had concomitant portal vein thrombosis. The mean age‐standardised incidence and prevalence rates in 1990–2001 were calculated to be 0.8 per million per year and 1.4 per million inhabitants respectively. Myeloproliferative disorders (38%), thrombophilic factors (31%) and oral contraceptives (30%) were common aetiological factors. Two or more risk factors were present in 44%. In 23%, no risk factor was evident. The median follow‐up time was 2.7 years. Seventy‐two percent were on anticoagulant therapy during follow‐up. Transjugular intrahepatic portosystemic shunting, surgical shunting procedures and liver transplantation were performed in 4, 6 and 18 patients respectively. Nineteen patients died. The overall transplantation‐free survival at 1, 5 and 10 years was 47, 28 and 17% respectively. Conclusions: Budd‐Chiari syndrome is a rare disorder; the mean age‐standardised incidence and prevalence rates in Sweden in 1990–2001 were calculated to be 0.8 per million per year and 1.4 per million inhabitants respectively. The presence of a myeloproliferative disorder was a common aetiological factor in our cohort and about half of the patients had a multifactorial aetiology. The transplantation‐free survival was poor.     

Leukocyte depletion of random single-donor platelet transfusions does not prevent secondary human leukocyte antigen-alloimmunization and refractoriness: a randomized prospective study

We studied the value of leukocyte depletion of platelet transfusions for the prevention of secondary human leukocyte antigen (HLA)- alloimmunization in patients with a high-risk of prior immunization induced by pregnancies. Seventy-five female patients with hematologic malignancies (mostly acute leukemia) and a history of pregnancy were randomized to receive either standard random single-donor platelet transfusions (mean leukocytes, 430 x 10(6) per transfusion) or leukocyte-depleted random single-donor platelet transfusions. Leukocyte depletion to less than 5 x 10(6) leukocytes per platelet transfusion (mean leukocytes, 2 x 10(6) per transfusion) was achieved by filtration. Of the 62 evaluable patients, refractoriness to random donor platelets occurred in 41% (14 of 34) of the patients in the standard group and in 29% (8 of 28) of the patients in the filtered group (P = .52); anti-HLA antibodies developed in 43% (9 of 21) of individuals in the standard group and 44% (11 of 25) of cases in the filtered group. The time toward refractoriness and development of anti- HLA antibodies was similar for both groups. We conclude that leukocyte depletion of random single-donor platelet products to less than 5 x 10(6) per transfusion does not reduce the incidence of refractoriness to random donor platelet transfusion because of boostering of anti-HLA antibodies.     

Gender differences in clinical outcomes of acute myocardial infarction undergoing percutaneous coronary intervention: insights from the KAMIR-NIH Registry

BackgroundThere are numerous but conflicting data regarding gender differences in outcomes following percutaneous coronary intervention (PCI). Furthermore, gender differences in clinical outcomes with acute myocardial infarction (AMI) following PCI in Asian population remain uncertain because of the under-representation of Asian in previous trials.MethodsA total of 13, 104 AMI patients from Korea Acute Myocardial Infarction Registry-National Institute of Health (KAMIR-NIH) between November 2011 and December 2015 were classified into male (n = 8021, 75.9%) and female (n = 2547, 24.1%). We compared the demographic, clinical and angiographic characteristics, 30-days and 1-year major adverse cardiac and cerebrovascular events (MACCE) in women with those in men after AMI by using propensity score (PS) matching.ResultsCompared with men, women were older, had more comorbidities and more often presented with non-ST segment elevation myocardial infarction (NSTEMI) and reduced left ventricular systolic function. Over the median follow-up of 363 days, gender differences in both 30-days and 1-year MACCE as well as thrombolysis in myocardial infarction minor bleeding risk were not observed in the PS matched population (30-days MACCE: 5.3% vs. 4.7%, log-rank P = 0.494, HR = 1.126, 95% CI: 0.800-1.585; 1-year MACCE: 9.3% vs. 9.0%, log-rank P = 0.803, HR = 1.032, 95% CI: 0.802-1.328; TIMI minor bleeding: 4.9% vs. 3.9%, log-rank P= 0.215, HR = 1.255, 95% CI: 0.869-1.814).ConclusionsAmong Korean AMI population undergoing contemporary PCI, women, as compared with men, had different clinical and angiographic characteristics but showed similar 30-days and 1-year clinical outcomes. The risk of bleeding after PCI was comparable between men and women during one-year follow up.     

Erythrocytapheresis therapy to reduce iron overload in chronically transfused patients with sickle cell disease

Chelation therapy with deferoxamine is effective in preventing the risk of transfusional iron overload, but treatment failure is common because of noncompliance. To reduce the transfusional iron load, we have evaluated longterm erythrocytapheresis in 14 subjects with sickle cell disease and stroke (11) or other complications (3) as an alternative to simple transfusion. Subjects were treated with erythrocytapheresis using the Haemonetics V50 (Haemonetics Corp, Braintree, MA) to maintain the target pretransfusion hemoglobin S (Hb S) level less than 50% for 6 to 71 months. The transfusional iron load and the donor blood usage were analyzed for a 6- to 36-month study period and were compared with similar data from a subset of 7 subjects previously treated with conventional (target Hb S < 30%) and modified (target Hb S < 50%) simple transfusion protocols. The effect of erythrocytapheresis on iron accumulation was determined by assessment of serum ferritin levels in the absence of iron chelation. The mean transfusional iron load and donor blood usage with erythrocytapheresis were 19 +/- 14 mg iron/kg/yr (range, 6 to 50) and 188.4 +/- 55.2 mL packed-red blood cells (RBC)/kg/yr (range, 107 to 281), respectively. Of 6 subjects receiving no iron chelation therapy, 5 maintained normal or nearly normal serum ferritin levels during 11 to 36 months of erythrocytapheresis. In comparison with conventional simple transfusion and modified simple transfusion, erythrocytapheresis reduced iron loading by 87% (P < .01) and 82% (P < .01), respectively, but increased donor blood usage by 23% and 73%, respectively. Subjects with pre-erythrocytapheresis Hb levels > or = 8.0 g/dL had lower iron accumulation (P < .001) and less donor blood usage (P < .005) than subjects with Hb levels < or = 8.0 g/dL. Although donor blood usage is increased in comparison with simple transfusion, long-term erythrocytapheresis markedly reduces or prevents iron accumulation. This form of transfusion therapy allows the cessation of iron chelation in well-chelated subjects and, if used as the initial form of transfusion therapy, may prevent long-term complications of sickle cell disease without risk of iron overload and the need for chelation therapy.     

Bedside filtration of blood products in the prevention of HLA alloimmunization--a prospective randomized study. Alloimmunisation Study Group

To test the efficacy of poststorage bedside leucodepletion of blood products in the prevention of primary HLA alloimmunization and its clinical sequelae, 172 patients with hematologic malignancy requiring intensive red blood cell and platelet support were randomized to receive either standard or filtered red blood cells and platelets. Quality control of bedside filtration was explored by sequential sampling downstream of the filter, but this did not predict the total number of leucocytes transfused. After exclusions, 123 evaluable patients were assessed every two weeks until the end of therapy. HLA antibodies developed in 21 of 56 (37.5%) nonfilter (NF) and 15 of 67 (22%) filter (F) patients (risk ratio estimate, 0.60 [95% confidence interval, 0.34 to 1.05]; P = .07). Patients with acute myeloid leukemia (AML; n = 53) had higher alloimmunization rates in both arms of the study, with a greater effect of filtration (62.5% NF and 31.0% F; P = .025). Bedside filtration did not affect the overall incidence of febrile transfusion reactions (FTRs; 37% NF and 34% F; P = .71) or of platelet refractoriness assessed in 50 patients (30% NF and 26% F), despite an association between broad HLA reactivity and both FTRs and refractoriness. However, FTRs were also seen in 28 patients without HLA antibodies. Five alloimmunized refractory patients (2 F and 3 NF) required HLA-selected platelets. This report, the first prospective study of bedside filtration, has failed to show clear clinical benefit. Methodological limitations may account in part for this failure, notably the difficulties in accurately assessing the number of leucocytes transfused.     

Increased red blood cell deformability due to isoxsuprine administration decreases platelet adherence in a perfusion chamber: a double-blind cross-over study in patients with intermittent claudication

Platelet transport towards the vessel wall is influenced by the hematocrit, red blood cell (RBC) size, and shape. Recent in vitro studies have indicated that RBC deformability may also influence platelet transport. The observation that isoxsuprine, a known vasodilating drug, caused increased RBC deformability in vitro and decreased platelet transport in vitro prompted us to study the effects of this drug in vivo. The study was performed in a double-blind cross- over study of isoxsuprine v placebo in ten patients with peripheral arterial insufficiency. RBC deformability was estimated from viscosity measurements using the blood viscosity equation of Dintenfass and expressed as T value. Platelet transport was studied in an annular perfusion chamber according to Baumgartner. Human umbilical arteries were used as blood vessels. Perfusion studies were performed with whole blood or with RBCs of the patients mixed with normal platelets and plasma at a standardized hematocrit and platelet count. An increase in RBC deformability concomitant with a decrease in platelet adherence was observed in patients on isoxsuprine with a drop in T value of approximately 0.06 (from 0.91 toward 0.86), and a concomitant decrease in platelet adherence of 20% to 40%. These observations differed significantly from the results in the placebo group and showed a significant group-period interaction at the cross-over of medication (analysis of variance). The effects on platelet adherence were observed at high vessel wall shear rate (1,800 s-1) with perfusates consisting of patients' RBCs and donor plasma and platelets at standardized hematocrit and platelet count. No differences were observed under these conditions at a shear rate of 300 s-1. When whole blood of patients was used, nonsignificant effect was observed at shear rates of 300 s-1 and 1,800 s-1. This was probably caused by the added noise due to variations in hematocrit and platelet number. These data demonstrate that isoxsuprine increases RBC deformability, and they suggest the possibility of decreasing platelet-vessel wall interaction in vivo by manipulation of RBC deformability.     

Autoimmune hemolytic anemia in Kawasaki disease: a case report

A 3-year-old boy presented with the fever, conjunctivitis, rash, and lymphadenopathy diagnostic of Kawasaki disease. Treatment with antibiotics, aspirin, and intravenous immunoglobulin was instituted. The hematocrit decreased from 35 percent on admission to 11 percent by hospital Day 10, and the white cell count had increased from 13.7 to 42 × 10(3) per microL, and the patient had a leukoerythroblastic blood smear. The direct antiglobulin test demonstrated IgG but not complement on the red cell (RBC) surface. An acid eluate reacted (titer of 4) with all panel cells in the antiglobulin phase. Intravenous immunoglobulin from the same lot used for treatment did not contain antibody that reacted with the patient's group O RBCs or a panel of group O RBCs, but did contain IgG anti-A and -B (titer of 4). The patient received a transfusion and was given methylprednisone. The direct antiglobulin test and acid eluate were negative 4 days later. The patient had an uneventful recovery. The distinction between antibody-mediated hemolytic anemia and autoimmune hemolytic anemia is important in the treatment of this disease.