Israel Medical Association Journal

Objectives: To evaluate the effect of vitamin D analogues on cardiac function and fibrosis in an animal model of cardiorenal syndrome.

Methods: Unilateral nephrectomy was performed and myocardial infarction induced in rats. Rats were treated with vitamin D receptor activator (VDRA, paricalcitol, 40 ng/250 g x 3/week) versus a vehicle. A third group of animals, which served as the control, underwent sham surgery and received no treatment. After 4 weeks of treatment, cardiac function and fibrosis were assessed by trans-thoracic echo and histology, respectively. As a parameter of systemic inflammation, previously shown to be altered in acute coronary syndrome, T regulatory (Treg) cell levels were measured by flow cytometry. Renal dysfunction was documented by standard laboratory tests.

Results: After 4 weeks of treatment, no significant improvement in cardiac function parameters was noted following VDRA administration. VDRA treatment did not significantly alter Treg cell systemic levels. Consistently, despite a trend toward less extent of myocardial fibrosis, we found no clear beneficial effects of VDRA on myocardial tissue inflammation and remodeling.

Conclusions: Vitamin D treatment showed no beneficial effects on cardiac function parameters and fibrosis in an animal model of cardiorenal syndrome. 

Background: Janus kinase-2 (JAK2) is mutated in a high proportion of patients with polycythemia vera and in a smaller number with essential thrombocythemia and primary myelofibrosis. Mutated JAK2 is an important diagnostic marker for myeloproliferative neoplasm (MPN) and may also play a major role in the pathogenesis of MPN.

Objectives: To evaluate the prevalence of mutated JAK2 (JAK2-V617F) among patients with major intraabdominal vein thrombosis who had normal blood counts at diagnosis of the initial event.

Methods: The medical records of patients who presented with a major intraabdominal venous thrombosis and normal peripheral blood counts were obtained. JAK2-V617F mutation status was determined by real-time polymerase chain reaction.

Results: Twenty-two patients were available for this analysis and 9 (41%) were found to have JAK2-V617F. Patients with positive JAK2-V617F were younger and had more frequent clinical splenomegaly than those with wild-type JAK2.

Conclusions: A high proportion of patients presenting with “idiopathic” major intraabdominal vein thrombosis and normal blood counts carry JAK2-V617F. We recommend searching for the mutation in this clinical setting to detect patients with occult MPN.

Objective: To assess the impact of multiple births on the severity of RSV infection and define risk factors for acquiring RSV infection in infants of multiple birth.

Methods: Clinical data on infants hospitalized with RSV infection between 2008 and 2010 were retrospectively collected.

Results: Twins comprised 7.6% (66/875) of hospitalized infants with RSV bronchiolitis during the study period. Infants in the twin group were younger (122.4 ± 131.7 vs. 204.5 ± 278.8 days, P = 0.014), had a lower mean gestational age (35.3 ± 2.6 vs. 38.6 ± 2.5 weeks, P < 0.001), and were more likely to have been born prematurely compared with singleton infants (65.6% vs. 13%, P < 0.001). On a multivariable logistic regression analysis, young age, early gestational age and male gender were the only variables identified as risk factors for pediatric intensive care unit admission (P < 0.001, P < 0.001 and P = 0.03, respectively). In contrast, the mere fact of a child being a twin was not found to be a significant risk factor for disease severity. In addition, if one twin is hospitalized due to RSV infection, the other has a 34% chance of also being hospitalized with bronchiolitis. Young age was a significant risk factor for hospitalization of the second twin (P < 0.001).

Conclusions: Our findings suggest that twins hospitalized with RSV bronchiolitis do not have an increased risk for severe infection as compared to singletons. However, a twin of an infant hospitalized with RSV infection has a considerable risk of also being hospitalized with bronchiolitis, thus close monitoring is recommended. 

Objectives: To assess the preliminary results of transcatheter mitral valve leaflet repair (TMLR) in a single academic center.

Methods: Data were collected prospectively in the cardiology department of Rabin Medical Center in 2012. Ten consecutive patients (age 69.3 ± 15.9 years, ejection fraction 36.5 ± 9.4) who were poor surgical candidates with severe functional MR underwent general anesthesia, followed by trans-septal puncture and a TMLR procedure using the MitraClip device.

Results: All 10 patients were considered to have severe functional MR prior to TMLR treatment and were all symptomatic; the mean New York Heart Association (NYHA) class was 3.4 ± 0.5. The MR severity was 4 ± 0. There were no immediate complications or failures of the procedure. One patient died on day 5 due to massive gastrointestinal bleeding. Immediately following TMLR all 10 patients showed a profound MR reduction to a mean severity grade of 1.6 ± 0.6. At one month after the procedure, NYHA had decreased to an average of 1.7 ± 1.0 and was at least grade 2 in all but one patient. After 6 months the MR remained ≤ 2 in six of eight patients, with a NYHA average of 1.4 ± 0.5.

Conclusions: The MitraClip procedure was shown to be relatively safe, providing significant clinical benefits to a relatively sick population with severe MR. It is therefore an important alternative to surgery in these high risk patients.

Objectives: To investigate the 30 day clinical outcome of the first 300 consecutive patients treated with transfemoral TAVI at the Tel Aviv Medical Center.

Methods: The CoreValve was used in 250 patients and the Edwards-Sapien valve in 50 patients. The mean age of the patients was 83 ± 5.3 years (range 63–98 years) and the mean valve area 0.69 ± 0.18 cm² (range 0.3–0.9 cm²); 62% were women.

Results: The procedural success rate was 100%, and 30 day follow-up was done in all the patients. The average Euro-score for the cohort was 26 ± 13 (range 1.5–67). Total in-hospital mortality and 30 day mortality were both 2.3% (7 patients). Sixty-seven patients (22%) underwent permanent pacemaker implantation after the TAVI procedure, mostly due to new onset of left bundle brunch block and prolonged PR interval or to high degree atrioventricular block. The rate of stroke was 1.7% (5 patients). Forty-one patients (13.7%) had vascular complications, of whom 9 (3%) were defined as major vascular complications (according to the VARC definition).

Conclusions: The 30 day clinical outcome in the first 300 consecutive TAVI patients in our center was favorable, with a mortality rate of 2.3% and low rates of stroke (1.7%) and major vascular complications (3%).

Background: Anti-red blood cell antibodies, free light chains (FLC) and prothrombotic proteins (PTP) may co-elute with intact immunogIobulin (IgG), and may be the cause of adverse reactions to intravenous immunoglobulin preparations (IVIG).

Objectives: To investigate the presence of residual amounts of these components in IVIG and their effects on ABO blood group agglutination.

Methods: Iso-agglutinin anti-A and anti-B activity was determined with a direct hemagglutination assay of red blood cell (RBC) suspensions from 1% of 46 blood donors together with the serial dilutions of five IVIG (IV1, IV2, IV3, IV4, IV5). Anti-A1 monoclonal antibody was used to confirm reactivity with the A1-reference RBC. The selected IVIG were diluted to a final concentration of 25 mg/ml in 0.15 M NaCl and 0.01 M phosphate-buffered saline (PBS), pH 7.4, with or without a further twofold dilution in a low ionic strength solution.

Results: A variation up to fivefold in the titer strength of anti-A/B activity was observed between the IVIG preparations. A2-type RBC required higher IVIG inputs when tested in 0.15 M NaCl. The differences in FLC kappa and lambda concentrations were as high as > 400 mg/L among the various IVIG. Only IV1 had a significantly high level of antiphospholipid IgG antibodies (18 U/ml). We demonstrated the presence of anti-RBC antibodies, FLC and PTP in IVIG preparations.

Conclusions: Our findings provide clear evidence that IVIG may harbor pathophysiological substrates with a potential risk for adverse effects such as iatrogenic hemolysis, FLC-associated disorders, and thromboembolism.