Israel Medical Association Journal

Background: Injuries to the anterior cruciate ligament (ACL) are common and complete tears often fail to heal. ACL reconstruction is considered the surgical gold standard of care for ACL injuries in young active patients.

Objectives: To determine the corresponding morphological and histological features of the torn ACL in different time periods after injury.

Methods: The study included 28 remnant specimens of torn ACLs from patients who had ACL reconstruction surgery of the knee. The remnant pathology was evaluated by its morphology during arthroscopy and by histopathologic measurements.

Results: At surgery there were three progressive and distinct morphological tear patterns. The first pattern was noticed within the first 3 months from injury and showed no scar tissue. The second pattern appeared later and was characterized by the appearance of scar tissue with adhesion to the femoral wall. The third pattern was characterized by adhesion of the ACL remnant to the posterior cruciate ligament. The histological changes of the first morphological pattern showed abundance of blood vessels and lymphocytes at the torn femoral end with few irregular collagen fibers. The second and third tear patterns showed decrement in the number of blood vessels and lymphocytes with longitudinally oriented collagen fibers.

Conclusions: The morphological features of the ACL remnant in the first 3 months after injury showed no scar tissue and its histological features had the characteristics of a reparative phase. This phase was followed by a prolonged remodeling phase that ended with attachment of the remnant to the posterior cruciate ligament.

Background: In contrast to the relative scarcity of donor kidneys and hearts, the potential supply of deceased donor pancreata is exceeding the demand. However, this potential organ surplus is not being fully realized because in current transplantation practice the duration of pancreas storage before transplantation is limited and many organs with established or anticipated cold ischemia time exceeding 8–10 hours are discarded owing to the extreme vulnerability of pancreatic tissue to anaerobic damage caused by preservation.

Objectives: To reduce cold ischemic injury in order to increase the utilization of donor pancreases in Israel for whole-organ and cell transplantation.

Methods: We evaluated a novel two-layer preservation oxygenated cold storage method that uses perfluorocarbon to continuously supply oxygen to the pancreas during preservation in conventional University of Wisconsin solution.

Results: Pancreatic tissue morphology, viability and adenosine-triphosphate content were serially examined during preservation of the pig pancreas for 24 hours either by a two-layer or by conventional simple cold storage. Already after 12 hours of storage, the superiority of the two-layer method over the University of Wisconsin method was apparent. Starting at this time point and continuing throughout the 24 hours of preservation, the tissue architecture, mitochondrial integrity, cellular viability and ATP[1] tissue concentration were improved in samples preserved in oxygenated UW[2]/PFC[3] as compared to controls stored in conventional UW solution alone.

Conclusions: The UW/PFC two-layer preservation method allowed tissue ATP synthesis and amelioration of cold ischemic tissue damage during extended 24 hour pancreas preservation. This method could be implemented in clinical practice to maximize utilization of pancreata for whole-organ and islet transplantation as well as for pancreas sharing with remote centers.

Background: Idiopathic left ventricular tachycardia with a right bundle branch block configuration and left axis deviation, first described by Belhassen et al., is a rare electrocardiographic-electrophysiologic entity. Radiofrequency catheter ablation has been proposed as a good therapeutic option, but the best criteria for determining the optimal site of ablation are still under debate.

Objectives: To report the clinical features, electrophysiologic characteristics, results of RFA[1], and long-term outcome in 18 patients with "Belhassen's VT” treated in our laboratory during the last 10 years, stressing the best electrophysiologic criteria for determining the optimal site of ablation.

Methods: Eighteen consecutive patients with this specific VT[2] underwent RFA in our laboratory during the last 10 years. RFA was acutely successful in 17 patients after one or two procedures (15 and 2 patients, respectively) using 4.1 ± 2.2 RF pulses. The putative ablation sites were defined by good pace-mapping (3 patients), earliest recorded Purkinje spike prior to the QRS onset during VT or sinus rhythm (6 patients), earliest endocardial activation during VT (1 patient), and diastolic potential preceding the Purkinje spike during VT and/or late diastolic potential in sinus rhythm (7 patients). In the patients with a definite successful ablation, the ratio of successful to unsuccessful radiofrequency pulse delivery to the diastolic potential site was compared to that of other methods. The ratio of successful RFA at the diastolic potential site (5:8) was higher than in the other methods (8:31), and the difference was statistically significant (P = 0.05). Successful ablation sites were more basal when the diastolic potential site was chosen.

Conclusion: The results of the present study confirm the high success rate and safety of RFA using conventional techniques in the management of “Belhassen VT,” suggesting that this procedure can be proposed as a first-line therapy. Ablating at a site demonstrating a late diastolic potential is at least as effective as ablating at a ventricular exit site, although the use of combined electrophysiologic criteria may be the optimal approach.