Improved Risk Stratification for Ventricular Arrhythmias and Sudden Death in Patients With Nonischemic Dilated Cardiomyopathy

BackgroundRisk stratification for ventricular arrhythmias (VA) and sudden death in nonischemic dilated cardiomyopathy (DCM) remains suboptimal.ObjectivesThe goal of this study was to provide an improved risk stratification algorithm for VA and sudden death in DCM.MethodsThis was a retrospective cohort study of consecutive patients with DCM who underwent cardiac magnetic resonance with late gadolinium enhancement (LGE) at 2 tertiary referral centers. The combined arrhythmic endpoint included appropriate implantable cardioverter-defibrillator therapies, sustained ventricular tachycardia, resuscitated cardiac arrest, and sudden death.ResultsIn 1,165 patients with a median follow-up of 36 months, LGE was an independent and strong predictor of the arrhythmic endpoint (hazard ratio: 9.7; p < 0.001). This association was consistent across all strata of left ventricular ejection fraction (LVEF). Epicardial LGE, transmural LGE, and combined septal and free-wall LGE were all associated with heightened risk. A simple algorithm combining LGE and 3 LVEF strata (i.e., ≤20%, 21% to 35%, >35%) was significantly superior to LVEF with the 35% cutoff (Harrell’s C statistic: 0.8 vs. 0.69; area under the curve: 0.82 vs. 0.7; p < 0.001) and reclassified the arrhythmic risk of 34% of patients with DCM. LGE-negative patients with LVEF 21% to 35% had low risk (annual event rate 0.7%), whereas those with high-risk LGE distributions and LVEF >35% had significantly higher risk (annual event rate 3%; p = 0.007).ConclusionsIn a large cohort of patients with DCM, LGE was found to be a significant, consistent, and strong predictor of VA or sudden death. Specific high-risk LGE distributions were identified. A new clinical algorithm integrating LGE and LVEF significantly improved the risk stratification for VA and sudden death, with relevant implications for implantable cardioverter-defibrillator allocation.     

Ubiquitylation of synphilin-1 and alpha-synuclein by SIAH and its presence in cellular inclusions and Lewy bodies imply a role in Parkinson's disease

Parkinson's disease (PD) is a neurodegenerative disease characterized by Lewy body formation and death of dopaminergic neurons. Mutations in alpha-synuclein and parkin cause familial forms of PD. Synphilin-1 was shown to interact with alpha-synuclein and to promote the formation of cytosolic inclusions. We now report that synphilin-1 interacts with the E3 ubiquitin-ligases SIAH-1 and SIAH-2. SIAH proteins ubiquitylate synphilin-1 both in vitro and in vivo, promoting its degradation by the ubiquitin-proteasome system. Inability of the proteasome to degrade synphilin-1/SIAH complex leads to a robust formation of ubiquitylated cytosolic inclusions. Ubiquitylation is required for inclusion formation, because a catalytically inactive mutant of SIAH-1, which still binds to synphilin-1, fails to promote inclusions. Like synphilin-1, alpha-synuclein associates with SIAH in intact cells, but the interaction with SIAH-2 was much stronger that with SIAH-1. In vitro experiments show that SIAH-2 monoubiquitylates alpha-synuclein. Further evidence that SIAH proteins may play a role in inclusion formation comes from the demonstration of SIAH immunoreactivity in Lewy bodies of PD patients.     

Hybrid long-term temporary pacing

Prolonged temporary pacing is associated with frequent complications. We describe a patient with aortic endocarditis and acquired tri-fascicular block in whom back-up pacing was indicated. Using a Seldinger technique via a subclavian approach, a permanent active-fixation lead was positioned in the right ventricle. The lead was tunnelled subcutaneously for 6 cm, and the proximal end was connected to a standard single chamber pulse generator. The procedure was well tolerated and over a period of four months there were no complications or infection. The PR interval subsequently reduced in duration to 200 ms and as no episodes of AV block had occurred, the lead was easily removed with retraction of the helix and gentle traction.     

Polydrug Use in Adolescent Drinkers with and without DSM-IV Alcohol Abuse and Dependence

Alcohol and other substance use disorders are highly comorbid, but little is known about patterns of polydrug use in adolescents with different levels of alcohol involvement. This research examined patterns and correlates of polydrug use in 176 adolescent drinkers with DSM-IV alcohol dependence ( n = 61), alcohol abuse ( n = 57), and no alcohol diagnosis ( n = 58). Alcohol and other Substance Use Disorders were assessed using a modified version of the Structured Clinical Interview for the DSM. Lifetime histories of alcohol use and other drug use were assessed using a structured interview. Subjects also completed a questionnaire measure of the frequency of use of specific alcohol-drug combinations. The total number of illicit drugs ever used was greater in the alcohol dependence (mean = 3.8, SD = 2.1) and abuse groups (mean = 3.0, SD = 2.1), compared with the no-alcohol diagnosis group (mean = 1.9, SD = 1.3). Consistent with previous findings, there was a consistent pattern in the age of onset of psychoactive substance use: alcohol, followed by marijuana, followed by other drugs. The recent use of alcohol and other drugs in combination was reported by a greater percentage of subjects in the alcohol dependence (69%) and abuse groups (72%), compared with drinkers without an alcohol diagnosis (45%). The most common alcohol-drug combination was alcohol with marijuana (58% of the total sample), followed by alcohol-hallucinogens (16%). The frequency and extent of polydrug use was associated with being older and having higher levels of behavioral undercontrol and negative emotionality. Adolescent polydrug use, particularly the use of alcohol and other drugs in combination, is an important area for research, treatment, and prevention.     

Myocardial infarction as a presentation of clinical in-stent restenosis.

BACKGROUND: In-stent restenosis is considered to be a gradual and progressive condition and there is scant data on myocardial infarction (MI) as a clinical presentation. METHODS AND RESULTS: Of 2,462 consecutive patients who underwent percutaneous coronary intervention between June 2001 and December 2002, clinical in-stent restenosis occurred in 212 (8.6%), who were classified into 3 groups: ST elevation MI (STEMI), non-ST elevation MI (NSTEMI) and non-MI. Of the 212 patients presenting with clinical in-stent restenosis, 22 (10.4%) had MI (creatine kinase (CK)>or=2xbaseline with elevated CKMB). The remaining 190 (89.6%) patients had stable angina or evidence of ischemia by stress test without elevation of cardiac enzymes. Median interval between previous intervention and presentation for clinical in-stent restenosis was shorter for patients with MI than for non-MI patients (STEMI, 90 days; NSTEMI, 79 days; non-MI, 125 days; p=0.07). Diffuse in-stent restenosis was more frequent in MI patients than in non-MI patients (72.7% vs 56.3%; p<0.005). Renal failure was more prevalent in patients with MI than in those without MI (31.8% vs 6.3%, p=0.001). Compared with the non-MI group, patients with MI were more likely to have acute coronary syndromes at the time of index procedure (81.8% vs 56.8%, p=0.02). CONCLUSION: Clinical in-stent restenosis can frequently present as MI and such patients are more likely to have an aggressive angiographic pattern of restenosis. Renal failure and acute coronary syndromes at the initial procedure are associated with MI.     

Treatment of B-cell lymphomas with anti-idiotype antibodies alone and in combination with alpha interferon

Idiotypes are distinct clonal markers for B-cell lymphomas. Previously we reported the use of anti-idiotype antibodies in the therapy of patients with B-cell malignancies. Because synergy was demonstrated with the addition of alpha interferon to anti-idiotype antibodies in a murine lymphoma model, we performed a clinical trial combining these two agents. Here we provide an update of the original trial of anti-idiotype antibodies alone and report the outcome of the new combination trial. In 16 treatment courses of anti-idiotype antibodies alone there were seven partial responses and one complete response. In 12 courses of combination anti-idiotype antibody and alpha interferon there were two complete responses and seven partial responses. Substantial tumor regressions occurred with minimal toxicity in both trials even in patients refractory to conventional chemotherapy. Tumor specimens obtained at the time of disease progression often contained a preponderance of idiotype-negative lymphoma cells, suggesting that anti-idiotype antibody treatment exerted a strong antitumor effect against antigen-positive cells. Anti-idiotype antibodies have reproducible objective antitumor activity in B-cell lymphoma. The addition of alpha interferon may improve the initial rate of response to this treatment. Strategies that deal effectively with idiotype-negative lymphoma cells should improve the extent and duration of these responses.     

Intraobserver and interobserver variation in the histopathological assessment of liver allograft rejection. The Liver Transplantation Database (LTD) Investigators

A study to determine the reproducibility of histopathological findings and diagnoses of rejection was carried out on a series of 42 liver allograft needle biopsy specimens by five pathologists practicing at four liver transplant centers. Pathologists from each of the four centers read each slide independently on two different occasions and were asked to assess 12 histopathological features and render a diagnosis. For all histological variables, the intrarater agreement was higher than the interrater agreement. Moderate to excellent agreement occurred among the pathologists about all histological variables thought to be important in establishing the diagnosis of acute rejection (i.e., portal tract inflammation, subendothelial inflammation and bile duct damage). Other variables such as lobular disarray, bile duct proliferation and particularly arteritis, however, were only fairly or poorly reproducible. Surprisingly, the diagnosis of acute rejection was more reproducible than the individual histopathological findings that were thought to be the basis for the diagnosis. The agreement for the diagnosis of chronic rejection, however, varied according to observer. We noted that relatively inexperienced observers within this group had some difficulties agreeing with more experienced observers in establishing a diagnosis of chronic rejection. These findings demonstrate that the histopathological diagnosis of acute cellular liver allograft rejection is highly reproducible within a group of experienced pathologists and that this diagnosis can be pooled in a common data base with confidence.     

Effects of acute volume loading and hemorrhage on intestinal vascular capacitance: a mechanism whereby capacitance modulates cardiac output

BACKGROUND: Changes in intestinal vascular capacitance during acute volume loading and hemorrhage have not been described. OBJECTIVES: To determine the effects of volume loading and hemorrhage on the intestinal vascular pressure-volume relationship and cardiac output. PATIENTS AND METHODS: In 11 alpha-chloralose-anesthetized dogs, a pneumatic portal venous constrictor and catheter were positioned to increase and measure portal venous pressure (Ppv), respectively. Relative changes in intestinal blood volume (IBV) were determined by blood-pool scintigraphy and expressed as the percentage change from control values (taken as 100%). Ppv-IBV relationships were constructed by graded portal vein constriction. RESULTS: IBV and cardiac output increased by 60 6% and 178 48%, respectively, and Ppv increased from 5.8 0.9 mmHg to 13.2 1.8 mmHg after initial volume loading (40 mL/kg of an isotonic glucose-saline solution over 7 min). IBV gradually decreased and reached near-control values after 75 min. In seven dogs, hemorrhage (sufficient to decrease mean aortic pressure by 56 4%) decreased IBV and cardiac output to 88 4% and 52 3% of control values, respectively, and Ppv decreased to 3.2 0.8 mmHg. CONCLUSIONS: A sigmoid function curve defined the relationship between cardiac output and IBV. Cardiac output remained constant over a wide range (between approximately 95% and 135% of control IBV). Outside this range, insufficient dilation or constriction resulted in a marked increase or decrease in venous pressures and cardiac output. These data indicate that vasculature capacitance modulates cardiac output during acute volume loading and hemorrhage, thereby maintaining cardiac output relatively constant over a wide range of total vascular blood volume.