Israel Medical Association Journal

Background: The predictive value of electrophysiologic studies depends on the aggressiveness of the programmed ventricular stimulation protocol.

Objectives: To assess if non-inducibility with an "aggressive" protocol of PVS[1] identifies post-infarction patients with low ejection fraction (EF[2] ≤ 30%) who may safely be treated without implantable cardioverter defibrillator.

Methods: We studied 154 patients during a 9 year period. Our aggressive PVS protocol included: a) stimulus current five times the diastolic threshold (≤ 3 mA) and b) repetition of double and triple extrastimulation at the shortest coupling intervals that capture the ventricle.

Results: Sustained ventricular tachyarrhythmias were induced in 116 patients (75.4%) and 112 (97%) of them received an ICD[3] (EPS[4]+/ICD+ group). Of the 38 non-inducible patients, 34 (89.5%) did not receive an ICD (EPS-/ICD- group). In comparison to the EPS+/ICD+ group, EPS-/ICD- group patients were older (69 ± 10 vs. 65 ± 10 years, P < 0.05), had a lower EF (23 ± 5% vs. 25 ± 5%,  P < 0.05) and a higher prevalence of left bundle branch block (45.5% vs. 20.2%, P < 0.005). Follow-up was longer for EPS+/ICD+ patients (40 ± 26 months) than for EPS-/ICD- patients (27 ± 22 months) (P = 0.011). Twelve EPS+/ICD+ patients (10.7%) and 5 EPS-/ICD- patients (14.7%) died during follow-up (P = 0.525). Kaplan-Meier survival curves did not show a significant difference between the two groups (P = 0.18).
Conclusions: The mortality rate in patients without inducible VTAs[5] using an aggressive PVS protocol and who did not undergo subsequent ICD implantation is not different from that of patients with inducible arrhythmias who received an ICD. Using this protocol, as many as one-fourth of primary prevention ICD implants could be spared without compromising patient prognosis

Background: Stent thrombosis is a rare but devastating complication of coronary stent implantation. The incidence and potential predictors were assessed in a "real world” single center.

 Objectives: To examine whether socioeconomic status indeed affects the occurrence of stent thrombosis.

Methods: We searched our database for cases of "definite" stent thrombosis (according to the ARC Dublin definitions). Each case was matched by procedure date, age and gender; three cases of stenting did not result in stent thrombosis. Demographic and clinical parameters were compared and socioeconomic status was determined according to a standardized polling and market survey database.

Results: A total of 3401 patients underwent stent implantation in our hospital during the period 2004–2006. Their mean age was 63 ± 11 years, and 80% were males. Twenty-nine cases (0.85%) of “definite” sub-acute/late stent thrombosis were recorded. Mortality at 30 days was recorded in 1 patient (3.5%). Thrombosis occurred 2 days to 3 years after stent implantation. All patients presented with acute myocardial infarction. Premature clopidogrel discontinuation was reported in 60%. Patients with stent thrombosis had significantly higher rates of AMI[1] at the time of the initial procedure (76 vs. 32%, P < 0.001) and were cigarette smokers (60 vs. 28%, P < 0.001). Drug-eluting stents were used less in the stent thrombosis group. There was no difference in stent diameter or length between the two groups. Socioeconomic status was significantly lower at the stent thrombosis group, 3.4 ± 2.4 vs. 5.4 ± 2.6 (mean ± SD, scale 1–10, P < 0.01).

Conclusions: The incidence rate of stent thrombosis is at least 0.85% in our population. It appears in patients with significantly lower socioeconomic status and with certain clinical predictors. These results warrant stricter follow-up and support the policy of healthcare providers regarding patients at risk for stent thrombosis.

Background: Sporadic abdominal desmoid tumors are rare and data on these tumors as a distinct disease entity are lacking. Previous abdominal surgery, trauma, pregnancy and estrogen intake are considered risk factors. Although desmoidsare benign, invasion and a high recurrence rate are common.

Objectives: To evaluate outcomes of surgery for this rare disease.

Methods: Since 1995, 16 patients with pathologically confirmed desmoid tumor were operated on in our center. All familial adenomatous polyposis patients were excluded. A retrospective analysis of data was performed.

Results: Of the 16 patients 12 (75%) were females. Mean age was 40.5 years (range 24-70). Thirteen patients were symptomatic and 3 were incidentally diagnosed. All patients presented with an isolated mass; 7 (50%) originated in the abdominal wall, 6 (37.5%) were retroperitoneal and 3 were (18.8%) mesenteric. All tumors except one were completely excised. Morbidity was low with no mortality. One patient was reoperated due to involved margins. None of the patients had recurrence within a median follow-up of 64 months (range 5-143).

Conclusions: The perception of sporadic abdominal desmoids as tumors with a high recurrence rate (20-70%) is probably incorrect. Adequate surgery with wide margins leads to a very low recurrence rate; cure is a legitimate goal.
 

Background: Information regarding long-term survival after stroke in many countries is scarce.

Objectives: To both assess 5 year survival after stroke in the Israeli population and determine its independent prognostic factors.

Methods: We followed 616 people with acute stroke who were admitted consecutively to seven large general hospitals in Israel. The data were collected on admission to the hospital, at discharge, at 3, 6 and 12 months thereafter, and 5 years after the stroke.

Results: The 5 year cumulative probability of survival was 49.2% (95% CI 45.0–53.7%). In the multivariate Cox analysis, lower age and functioning independently before the event were associated with a lower risk of death, while other demographic characteristics and cardiovascular risk factors were not found to be associated with mortality.

Conclusions: Five year survival after stroke in Israel, though high, is similar to other western countries. There is a need to ensure early, active and sustained implementation of strategies for preventing stroke events.

Background: Unicompartmental knee replacement has become a surgical alternative for treating isolated medial or lateral osteoarthritis of the knee or avascular necrosis of the femoral condyls.

Objectives: To evaluate the short-term results of the Oxford Phase 3^® unicompartmental knee replacement for unicompartmental knee arthrosis or avascular necrosis of the medial

femoral condyle.

Methods: During the period 2003–2005 a total of 59 patients (59 knees) underwent medial Oxford Phase 3^® unicompartmental knee replacement in our unit. The patients were interviewed and examined, and standing anteroposterior and lateral X-rays were taken. All patients completed the Western Ontario and McMaster Universities Index of Osteoarthritis and the Short Form 12 questionnaire, and the International Knee Society score was evaluated. The data were collected and statistical analysis was performed.

Results: X-rays were performed and scores for the WOMAC[1] and IKS[2] were assessed for 42 patients (31 females, 11 males). At an average of 32 months after surgery, the total WOMAC score was 30. The mean SF[3]12 physical score was 38 and the mean SF12 mental score was 51. The mean IKS score was 166. Ninety-one percent of the patients had active flexion of 120 degrees or more. Of 59 knees 7 were converted to total knee arthroplasty – all of them within the first 2 years of starting the procedure and all of them in relatively young patients.

Conclusions: Despite the higher revision rate to TKR[4] in this study, our findings confirm the short-term results reported in other studies of the Oxford medial unicompartmental knee and our early failure rate could be explained by a performance learning curve. This study confirms that this bone-preserving procedure should be considered in end-stage isolated unicompartmental osteoarthritis or avascular necrosis by surgeons who have the adequate training and experience.

Background: The forced oscillation technique is a non-invasive and effort-independent technique and is well suited for lung function measurement in young children. FOT[1] employs small-amplitude pressure oscillations superimposed on normal breathing. Therefore, it has the advantage over conventional lung function techniques in that it does not require patient cooperation for conducting respiratory maneuvers.

Objectives: To test the feasibility of the FOT test in preschool children and to compare the results to the commonly used spirometry before and after the administration of bronchodilator therapy.

Methods: Forty-six children (median age 4.9 years, range 1.8–18.3) attending the Pulmonary Clinic at Schneider Children's Medical Center tried to perform FOT and routine spirometry. Results were retrospectively analyzed. 

Results: Of the 46 children 40 succeeded in performing FOT and only 29 succeeded in performing simple spirometry. All but one of the 32 children aged 4 years and above (97%) could perform both tests. Nine of 14 children (64%) aged 4 and less could perform the FOT but only 3 (21%) could perform spirometry. Baseline values of respiratory resistance measured at 6 Hz (R6) negatively correlated with body length (r² = 0.68, P < 0.005). Twenty-four children performed both tests before and after bronchodilator therapy. A significant concordance was found between the measured responses to bronchodilators by FOT and spirometry (P < 0.01). Only one child had a negative response by FOT but a positive response by spirometry.

Conclusions: The FOT is a simple, non-invasive technique that does not require subject cooperation and thus can be utilized for measuring lung function in children as young as 2 years of age. Furthermore, the FOT was shown to reliably measure response to bronchodilator therapy.

Background: Manganism is a central nervous system disorder caused by toxic exposure to manganese. Manganism has been related to occupational exposures, liver diseases, prolonged parenteral nutrition, and abuse of illicit drugs. Initially manifested by a reversible neuropsychiatric syndrome (locura manganica), the main symptoms and signs of manganism are emotional lability, compulsive behavior and visual hallucinations. Locura manganica is followed by an irreversible extrapyramidal syndrome, the onset of which occurs years after chronic exposure.

Objectives: To characterize the regional distribution of Mn[1] in the rat brain after subchronic exposure to Mn. This animal model holds special clinical relevance, reflecting the earlier clinical stages of manganism before chronic exposure to Mn exerts its irreversible effects.

Methods: Sprague-Dawley rats were intravenously injected with MnCl₂ weekly, for a total of 14 weeks – approximately 1/10 of the lifetime of the rat. T1-weighted magnetic resonance imaging was used to detect the distribution of Mn deposition in brain tissues, as evidenced by areas of T1-weighted hyperintense signals.

Results: A consistent region-specific pattern of T1-weighted hyperintensities was observed in the brains of Mn-treated rats. Cortical hyperintensities were prominent in the hippocampus and dentate gyrus. Hyperintensities were also observed in the olfactory bulbs, pituitary gland, optic nerves and chiasma, pons, midbrain tegmentum, habenula, lentiform and caudate nuclei, thalamus, chorioid plexus and cerebellar hemispheres.

Conclusions: Prominent Mn depositions, evidenced by T1-weighted hyperintensities in the hippocampus after subacute exposure to Mn, are compatible with the clinical picture of manganism during its early stages; and may explain its pathophysiology.  

Background: Ocular hypotony is a common unexplained feature of myotonic dystrophy type 1. Spuriously low applanation tonometric readings can be caused by thin corneas, flat corneal curvature and corneal edema.

Objectives: To determine whether structure abnormalities of the cornea cause spuriously low readings in applanation tonometry.

Methods: We utilized a TMS-2N corneal topographer, a NonconRobo SP-6000 Specular microscope and a Corneo-Gage Plus 1A Pachymeter to examine seven patients with DM1[1] and eight healthy controls. Intraocular pressure, central corneal thickness, and endothelial cell density were measured, and simulated keratometry readings were made. Cornea guttata and irregularity of corneal topography patterns were also sought.

Results: The mean intraocular pressure was 9.86 ± 1.29 mmHg for all patients (intraocular operated and non‑operated eyes) and 12.88 ± 1.89 mmHg for the controls (P = 0.000021, two-tailed t-test). Central corneal thickness was 530.57 ± 35.30 micron for all patients and 535.00 ± 39.62 micron for the controls (P = 0.75, two-tailed t-test). Endothelial cell density was 3164 ± 761 cells/mm² for all patients and 3148 ± 395 cells/mm² for the controls (P = 0.94, two-tailed t-test). Simulated keratometry readings were similar in both groups when the operated eyes were excluded. Cornea guttata and irregularity of corneal topography patterns were also noted in the study group.

Conclusions: Corneal thickness, corneal curvature and corneal hydration were within normal limits and thus were not the cause for the low applanation tonometry reading in DM1. The presence of cornea guttata and irregularity of corneal topography patterns in DM1 warrants further investigation.