Multiple clinical profiles of families with the short QT syndrome.

Aims: Short QT syndrome (SQTS) is a rare cardiac channelopathy characterized by a shortened corrected QT (QTc)-interval that can lead to ventricular arrhythmias and sudden cardiac death. The aim of this study was to investigate the clinical phenotypes and long-term outcomes of three families harbouring genetic mutations associated with the SQTS. Methods and results: Clinical data included medical history, physical examination, 12-lead ECG, 24-h Holter-ECG, and transthoracic echocardiography from three index patients and their first-degree relatives. Next generation clinical exome sequencing and genetic cascade screening were performed in index patients and their relatives, respectively. Two index patients experienced malignant ventricular arrhythmias and one patient suffered from arrhythmogenic syncope during a median follow-up period of 8 years. They all had genetic mutations associated with the SQTS. Two mutations were found in the KCNH2 gene, and one in the CACNA2D gene. One patient had an additional SCN10A variant. Alive and mutation-positive family members had short QTc-intervals, but no further phenotypic manifestations. None of the mutation-negative family members had an abnormal ECG or any symptoms. In all patients with shortened QTc-intervals, the QTc-interval had a low long-term variability and QTc shortening always remained detectable by 12-lead ECG. Conclusion: This study shows the variety of phenotypic manifestations in different families with SQTS. It further emphasizes the importance of a 12-lead ECG for early diagnosis, and the utility of next generation sequencing for the identification of mutations associated with the SQTS.

Electroanatomical voltage mapping with contact force sensing for diagnosis of arrhythmogenic right ventricular cardiomyopathy.

BACKGROUND: Three-dimensional electroanatomical mapping (EAM) can be helpful to diagnose arrhythmogenic right ventricular cardiomyopathy (ARVC). Yet, previous studies utilizing EAM have not systematically used contact-force sensing catheters (CFSC) to characterize the substrate in ARVC, which is the current gold standard to assure adequate tissue contact. OBJECTIVE: To investigate reference values for endocardial right ventricular (RV) EAM as well as substrate characterization in patients with ARVC by using CFSC. METHODS: Endocardial RV EAM during sinus rhythm was performed with CFSC in 12 patients with definite ARVC and 5 matched controls without structural heart disease. A subanalysis for the RV outflow tract (RVOT), septum, free-wall, subtricuspid region, and apex was performed. Endocardial bipolar and unipolar voltage amplitudes (BVA, UVA), signal characteristics and duration as well as the impact of catheter orientation on endocardial signals were also investigated. RESULTS: ARVC patients showed lower BVA vs. controls (p = 0.018), particularly in the subtricuspid region (1.4, IQR:0.5-3.1 vs. 3.8, IQR:2.5-5 mV, p = 0.037) and RV apex (2.5, IQR:1.5-4 vs. 4.3,IQR:2.9-6.1 mV, p = 0.019). BVA in all RV regions yielded a high sensitivity and specificity for ARVC diagnosis (AUC 59-78%, p < 0.05 for all), with the highest performance for the subtricuspid region (AUC 78%, 95% CI:0.75-0.81, p < 0.001, negative predictive value 100%). A positive correlation between BVA and an orthogonal catheter orientation (46°-90°:r = 0.106, p < 0.001), and a negative correlation between BVA and EGM duration (r = -0.370, p < 0.001) was found. CONCLUSIONS: EAM using CFSC validates previous bipolar cut-off values for normal endocardial RV voltage amplitudes. RV voltages are generally lower in ARVC as compared to controls, with the subtricuspid area being commonly affected and having the highest discriminatory power to differentiate between ARVC and healthy controls. Therefore, EAM using CFSC constitutes a promising tool for diagnosis of ARVC.

Bromelain in the early phase of healing in acute crush Achilles tendon injury.

UNLABELLED: Bromelain, an enzyme extracted from the stem of the pineapple plant has been proposed as a treatment for reducing pain and swelling following acute muscle injuries but studies are yet to be done on its effect on tendon healing. This study therefore investigated the effects of bromelain on tenocyte proliferation and the tendon malondialdehyde (MDA) level in the early stage of healing in a crush injury to the Achilles tendon of Sprague-Dawley rats. Twenty four male rats were divided randomly into three groups; groups 2 and 3 had induced crush injury to the left Achilles tendon. Group 1; nil injury and nil treatment, Group 2; nil treatment, Group 3; oral bromelain treatment. Bromelain was given at a dosage of 7 mg/kg body weight daily over the first 14 days post-injury. On day 15 post injury, the animals were killed and the tendons excised and processed for histological study and MDA assay. The results showed a significant increase in the tenocyte population in the bromelain group; p < 0.05. There was, however, no significant difference in the MDA level. CONCLUSION: Based on this study, 600 GDU bromelain given once daily in acute tendon injury at a dosage of 7 mg/kg promoted healing by stimulating tenocyte proliferation.

Effects of torsion, detorsion and melatonin on testicular malondialdehyde level.

BACKGROUND: Unilateral testicular torsion is a cause of bilateral testicular damage, which has ischaemic and reperfusion components. The damage may involve lipid peroxidation leading to production of lipid peroxides in the testes, including malondialdehyde (MDA). OBJECTIVE: To investigate the MDA variations in the ipsilateral and contralateral testes following ischaemia-reperfusion and the effect of melatonin. METHODS: Mature adult male Sprague-Dawley rats were divided into 13 groups of 10 each. One control group underwent sham operation. Three groups were subjected to right sided testicular torsion by twisting the testes 720 degrees counterclockwise for one, three and five hours; three groups were subjected to de-torsion following torsion lasting one, three and five hours; three groups were treated with intra-peritoneal melatonin (1 mg/kg) before torsion lasting one, three and five hours, and three groups were treated with intra-peritoneal melatonin before de-torsion following torsion lasting one, three and five hours. At the end of the experiment all animals were sacrificed by decapitation and testes were collected for MDA level estimation. RESULTS: The MDA level was significantly higher in ipsilateral torted testis than the control testis in all groups (P < 0.05), with the levels increasing with the duration of torsion. Detorsion significantly increased the MDA level only if the initial torsion was for less than three hours. Melatonin did not significantly affect the MDA level in the ipsilateral testis if administered before torsion, but significantly reduced the level if administered before detorsion. CONCLUSION: Malondialdehyde levels are altered in the both testes following unilateral testicular torsion-detorsion injuries. The reperfusion component of the injury is significant and may be reduced by melatonin.

Simple criteria for differentiation of Fabry disease from amyloid heart disease and other causes of left ventricular hypertrophy.

AIMS: Fabry disease may be difficult to differentiate from other causes of left ventricular hypertrophy such as other myocardial storage diseases (including amyloidosis), hypertrophic cardiomyopathy (HCM), or hypertensive heart disease (HHD). We sought to determine simple criteria to best differentiate the above mentioned cardiac diseases. METHODS AND RESULTS: All patients in a six-year time period with left ventricular hypertrophy due to Fabry disease (13 patients), biopsy proven cardiac amyloidosis (16 patients), non-obstructive HCM (17 patients), and 22 randomly selected patients with advanced HHD were compared. Retrospective analysis of clinical characteristics, findings of electrocardiogram (ECG) and echocardiography by blind review was performed. RESULTS: No single clinical characteristic or findings of ECG or echocardiography could reliably differentiate between the various diseases. Increased echogenicity/granular sparkling, valvular abnormalities, abnormal renal function, and diastolic function were not helpful discriminators. In a univariate analysis, four criteria (acroparesthesia, anhydrosis, absence of hypertension and presence of Sokolow criteria for left ventricular hypertrophy in the ECG) were significant for Fabry disease. By logistic regression analysis, the following most suitable discriminative parameters were identified: hypertension in HHD (specificity 82%), orthostasis and/or pericardial effusion for amyloidosis (specificity 93%), papillary muscle anomaly in non-obstructive HCM (specificity 92%), and Fabry disease if neither hypertension orthostatis, pericardial effusion nor a papillary muscle anomaly was present (specificity 87%). CONCLUSION: A combination of symptoms, echocardiographic findings and ECG in unexplained left ventricular hypertrophy may help to differentiate amyloidosis, non-obstructive HCM and hypertensive heart disease from Fabry disease. The results of this preliminary study will have to be confirmed in a prospective study.

Endothelin and cardiac arrhythmias: do endothelin antagonists have a therapeutic potential as antiarrhythmic drugs?

Endothelin-1 (ET-1), the predominant isoform of the ET peptide family and a potent vasoconstrictor, has been shown to aggravate ischemia-induced ventricular arrhythmias. However, there is also evidence that ET-1 may have a direct arrhythmogenic action that is not solely attributable to myocardial ischemia. Proposed mechanisms for the arrhythmogenic effects of ET-1 are prolongation or increased dispersion of monophasic action potential duration, QT prolongation, development of early afterdepolarizations, acidosis, and augmentation of cellular injury. As for an ionic basis for the observed electrophysiologic effects, ET-induced Ca(2+) release from intracellular stores, generation of inositol triphosphate, inhibition of delayed rectifier K(+) current, and stimulation of the Na(+)/H(+) exchanger may be involved. Recently, some studies have shown that ET receptor antagonists, which promise to be powerful tools in cardiovascular medicine, may also demonstrate antiarrhythmic properties. This review describes the current state of knowledge on the interactions between the ET system and cardiac arrhythmias, and discusses the therapeutic potential of ET antagonists as antiarrhythmic drugs.

Postmortem analysis of encapsulation around long-term ventricular endocardial pacing leads.

OBJECTIVE: To analyze the site and thickness of encapsulation around ventricular endocardial pacing leads and the extent of tricuspid valve adhesion, from today's perspective, with implications for lead removal and sensor location. MATERIAL AND METHODS: Gross cardiac postmortem analysis was performed in 11 cases (8 female and 3 male patients; mean age, 78+/-7 years). None of the patients had died because of pacemaker malfunction. The mean implant time was 61+/-60 months (range, 4 to 184). RESULTS: The observations ranged from encapsulation only at the tip of the pacing lead to complete encapsulation along the entire length of the pacing lead within the right ventricle. Substantial areas of adhesion at the tricuspid valve apparatus were noted in 7 of the 11 cases (64%). The firmly attached leads could be removed only by dissection, and in some cases, removal was possible only by damaging the associated structures. No specific optimal site for sensor placement could be identified along the ventricular portion of the pacing leads; however, the fibrotic response was relatively less prominent in the atrial chamber. CONCLUSION: Extensive encapsulation is present in most long-term pacemaker leads, which may complicate lead removal. The site and thickness of encapsulation seem to be highly variable. Tricuspid valve adhesion, which is usually underestimated, may be severe. In contrast to earlier reports, our study demonstrates that the extent of fibrotic encapsulation may not be related to the duration since lead implantation. Moreover, we noted no ideal encapsulation-free site for sensors on the ventricular portion of long-term pacing leads.

A comparison of the effect of high-dose methylprednisolone with conventional-dose prednisolone in acute lymphoblastic leukemia patients with randomization.

In this preliminary study the efficacy of high-dose methylprednisolone (HDMP) during remission-induction chemotherapy was evaluated on 166 children with acute lymphoblastic leukemia (ALL). The St. Jude Total Therapy Study XI protocol with minor modifications was used in this trial. Patients were randomized into two groups. Group A received conventional-dose (2 mg/kg/day orally) prednisolone, and group B received high-dose methylprednisolone (HDMP, Prednol-L, 900-600 mg/m2 orally) during remission-induction chemotherapy. Complete remission was achieved in 97% of the children. For the 80 patients who were followed up for 3 years, median follow-up was 44 (range 5-60) months and the 3-year event-free survival (EFS) rate was 68.5%) overall, 58.6% in group A and 78.4% in group B. The EFS among patients in group B was significantly higher than in group A (p=0.05). When we compared the 3-year EFS of groups A and B in the high-risk groups and high-risk subgroups with white blood cell (WBC) counts > or = 50 x 10(9)/l and age > or = 10 years, the survival rates were 45% versus 77.2%, 33% versus 78% and 45% versus 89%, respectively. During the follow-up of 162 patients, relapses were significantly higher in group A. Bone marrow relapses in 162 patients, and also in a subgroup of patients > or = 10 years of age were significantly higher in group A. These results suggest that HDMP during remission-induction chemotherapy improves long-term EFS, particularly for high-risk patients.

Sudden cardiac death after coronary artery bypass grafting is not predicted by signal-averaged ECG.

BACKGROUND: Sudden cardiac death (SCD) is a major cause of death despite successful revascularization in patients with coronary artery disease. The signal-averaged ECG (SAECG) is a sensitive predictor of SCD and could be used in the screening strategy to select patients for prophylactic cardioverter implantation. METHODS: The SAECG was recorded in 561 patients (mean age: 60 +/- 8.8 years) within 10 days of coronary artery bypass grafting. Signal-averaged ECG was performed with a bandpass filtering of 40 to 250 Hz for more than 250 beats until a noise level of 0.6 microV was achieved. All patients were followed for 5.5 +/- 1.2 years after the procedure. RESULTS: Preoperative angiographic ejection fraction was at least 60% in 393 patients (72%), 40% to 60% in 126 patients (23%), and 40% or less in 28 patients (5%). There were 34 deaths, 10 of which were SCD. Late potentials were found in a total of 150 patients (27%) and were equally frequent preoperatively and postoperatively and among patients with (30%) and without (27%) SCD. The only predictors for overall mortality were age and a reduced ejection fraction. CONCLUSIONS: Signal-averaged ECG did not predict prognosis in low-risk patients undergoing coronary artery bypass grafting.

Soluble L-selectin increases in the cerebrospinal fluid prior to meningeal involvement in children with acute lymphoblastic leukemia.

Soluble L-selectin was determined in the CSF samples of 20 children with CNS leukemia at the time they had blasts in CSF and/or clinical findings of CNS involvement; 17 CSF fluid samples were obtained from 17 of these 20 children, 29-91 days before the appearance of CSF cytological and/or clinical findings of CNS involvement; while 15 CSF samples were withdrawn from among the same group of children, after treatment of meningeal leukemia. In addition, CSF sL-selectin was also assayed in 17 children with ALL, who remained in complete remission at least for a year and, as controls, in 12 children without malignant or meningeal disorders. There was no significant difference in CSF sL-selectin levels between the children with ALL without evidence of meningeal involvement and the controls (1.34 +/- 0.21 ng/ml, 1.46 +/- 0.18 ng/ml respectively, p > 0.05). However, in children with CNS leukemia, not only at the time CNS involvement was diagnosed, but also 29-91 days before the diagnosis of CNS leukemia, the concentrations of the CSF sL-selectin (12.41 +/- 2.14 ng/ml, 7.70 +/- 1.60 ng/ml respectively) were significantly higher than those in controls (p < 0.001 and p < 0.01 respectively). After treatment and disappearance of the blasts in CSF, sL-selectin was found to be decreased and even normalized in the majority of children who had meningeal involvement (2.87 +/- 2.14 ng/ml). In 5 children, the CSF sL-selectin remained high, after the blasts in CSF had disappeared and CNS leukemia recurred within 3 months in 4 of these 5 children. In conclusion, assay of sL-selectin in CSF seems to be a good diagnostic tool in the detection of CNS involvement in children with ALL. This method may also be used as an indicator, in prediction of the CNS leukemia, which is going to develop.

High prevelance of chronic magnesium deficiency in T cell lymphoblastic leukemia and chronic zinc deficiency in children with acute lymphoblastic leukemia and malignant lymphoma.

Magnesium and zinc are the elements having essential roles in regulation of cell growth, division and differentiation. There have been some studies in the literature suggesting an association between the deficiency of these elements and the development of malignant disorders. In this study hair and serum zinc and magnesium levels were investigated in children with acute lymphoblastic leukemia (ALL) and malignant lymphoma (ML) at the time of initial diagnosis. Ten children with T-cell ALL, 10 children with B-precursor ALL, 5 children with Burkitt's Lymphoma (BL), 11 children with Hodgkin's lymphoma (HL), 10 children with non-Burkitt non-Hodgkin's lymphoma (NBNHL) and 12 age and sex matched healthy children as a control group were included in the study. Mean hair magnesium levels in all of the groups of the patients were lower than the levels in the control group but the difference was statistically significant only in the children with T cell ALL comparable to the controls (28.9+/-3.9 microg/g and 87.6+/-18.5 microg/g respectiveley, p<0,05). Mean serum magnesium levels in all the cohorts were not significantly different than those in controls (p>0.05 in each comparison). Mean hair zinc levels in the patients with T-cell, B-precursor ALL, BL, HL, NBNHL were 103.4+/-14.6 microg/g, 100.9+/-7.8 microg/g, 91.1+/-19 microg/g, 72.5+/-9.1 microg/g, 103.2+/-12.2 microg/g respectively. Each of these levels were significantly lower than the mean hair zinc levels of the control group (141.2+/-9.6 microg/g, p<0.05 in each comparison). Although mean serum zinc levels in all of the groups were also decreased, the differences were statistically significant only in the groups with B-precursor ALL, HL and NBNHL (75.9+/-5.29 microg/dl, 68.6+/-7.3 microg/dl, 85.7+/-5.5 microg/dl respectively) when compared with controls (105.1+/-9.9 microg/dl, p<0.05 in each comparison). Hair magnesium and zinc levels showed a positive correlation with each other in all the groups (r congruent with 0.5). No significant difference was found in the mean hair/serum magnesium and zinc levels between malnourished and nonmalnourished patients. In conclusion, regarding the results of our study and previous data in the literature chronic magnesium and zinc deficiency seems to be associated with the development of ALL and malignant lymphoma in a group of patients.

Coexistence of life threatening chemotherapy related leukoencephalopathy, saggital sinus thrombosis and multiple organ failure in a child with acute lymphoblastic leukemia: an unusual case with clinical recovery.

A nine-year old girl with T cell acute lymphoblastic leukemia (ALL) had acute severe neurologic complications at the end of the remission-induction chemotherapy course. Thirty-six hours following triple intrathecal (IT) therapy and intravenous (IV) administration of L-asparaginase (L-asp), tetraplegia developed and she became unconscious. She had bouts of hypertension and persistent tachycardia unresponsive to digitalis therapy. Magnetic resonance imaging (MRI) showed multiple brain white matter hyperintensities and filling defects in the saggital sinus, suggesting thrombosis. Over the 40 days, in addition to her neurologic compromise she also had transient diabetes mellitus, severe hyperlipidemia, hypoproteinemia and edema, liver and heart failure and staphylococcus aureus sepsis with prolonged bone marrow depression. Despite, coexistence of all these chemotherapy related complications, her neurologic functions and multiple organ failure improved gradually. After a 70 days' period of interruption, chemotherapy was resumed and continued without any further complications. Although, the etiology of her extensive sensitivity to some drugs remains unclear, we believe that it is important to document these unusual events in this child.

Threshold tracking pacing based on beat by beat evoked response detection: clinical benefits and potential problems.

Continuous monitoring of pacemaker stimulation thresholds and automatic adjustment of pacemaker outputs were among the longstanding goals of the pacing community. The first clinically successful implementation of threshold tracking pacing was the Autocapture feature which has accomplished automatic ventricular capture verification for every single stimulus by monitoring the Evoked Response (ER) signal resulting from myocardial depolarization. The Autocapture feature not only decreases energy consumption by keeping the stimulation output slightly above the actual threshold, but also increases patient safety by access to high-output back-up pulses if there is loss of capture. Furthermore, it provides valuable documentation of stimulation thresholds over time and serves as a valuable research tool. Current limitations for its widespread use include the requirements for implantation of bipolar low polarization leads and unipolar pacing in the ventricle. Fusion/pseudofusion beats with resultant insufficient or even non-existent ER signal amplitudes followed by unnecessary delivery of back-up pulses and a possible increase in pacemaker output is not an uncommon observation unique to the Autocapture feature. The recent incorporation of the Autocapture algorithm in dual chamber pacemakers has been challenging because of more frequent occurrence of fusion/pseudofusion beats in the presence of normal AV conduction. Along with a review of the previously published studies and our clinical experience, this article discusses the clinical advantages and potential problems of Autocapture.

Potential proarrhythmic effects of implantable cardioverter-defibrillators.

Implantable cardioverter-defibrillator (ICD) interventions have the potential to be proarrhythmogenic. New arrhythmias can occur in the setting of clinically appropriate therapies, as well as during a cardiac rhythm for which therapy is not intended. Cardioversion/defibrillation therapies, antitachycardia pacing, and antibradycardia pacing are potential triggers for the development of new arrhythmias. Newer ICDs allow better recognition and interpretation of the arrhythmias that are induced by delivered therapies. Two cases of ICD-induced proarrhythmias are described. Based on the course of these patients and review of previous reports, proarrhythmic effects of ICD interventions along with prevention and management strategies are discussed.

Vacuolated white blood cells in thalassemia major.

We report a case of thalassemia major in which severe cytoplasmic vacuolization was seen in white blood cells as well as in their precursors. Cytochemical examination of the vacuoles revealed Sudan Black staining. Consequently, we believe that our patient had Jordans' anomaly coexisting with thalassemia major.

The effect of high-dose methylprednisolone on CD34-positive bone marrow cells in the children with acute myeloblastic leukemia.

The expression of CD34 antigen on the surface of bone marrow (BM) cells during remission induction was studied in 20 patients with CD34-negative acute myeloblastic leukemia (AML). The patients were given high-dose methylprednisolone (HDMP) alone for one week, after which time mitoxantrone and low-dose Ara-C were added. BM cells from all patients were studied one, two and four weeks after initiation of treatment to evaluate CD34 antigen expression using a three-step peroxidase antiperoxidase staining technique. The mean percentage of CD34-positive BM cells was 5.3% at presentation, increasing to 15.6% in the first week, 12.9% in the second week and 21.7% in the fourth week of therapy. During the same period the mean percentages of the initial BM blasts decreased from 64% to 22%, 7% and 2% in the first, second and fourth weeks of therapy, respectively. The increase in the CD34-positive BM cells one week after HDMP treatment alone suggests that HDMP directly or indirectly stimulates CD34-positive hematopoietic progenitor cells while decreasing BM blasts in patients with AML.

[Cardiac arrhythmias--ECG and electrophysiologic assessment]. / Herzrhythmusstörungen--EKG und elektrophysiologische Abklärung.

The 12-lead resting surface ECG plays a major role in the diagnosis of cardiac arrhythmias. As a screening method, it provides important information about the cardiac rhythm and possible underlying heart diseases. It enables interpretation of possible arrhythmia mechanisms, especially if the recording is obtained at the time of the rhythm disorder. Since rhythm disorders exhibit spontaneous variability, event recorders and Holter monitoring are very helpful complementary noninvasive tools in the diagnosis of cardiac arrhythmias. In addition, Holter ECG can be used in monitoring the response to antiarrhythmic agents and in risk stratification of arrhythmias in certain cardiac disease states. Physical exercise, by inducing physiological and pathophysiological changes, may provoke arrhythmias, which forms the basis of exercise-stress testing. Stress testing may also be indicated when antiarrhythmic agents are initiated or therapy altered. Electrophysiological Study (EPS) is a time-consuming and costly investigation, which in general is reserved for further evaluation of tachyarrhythmias, conduction disturbances and syncope of unknown origin and routinely performed prior to radiofrequency ablation. EPS should only be performed in tertiary-care centers by well-trained and experienced cardiac electrophysiologists.

[Stress, depression and cardiac arrhythmias]. / Stress, Depression und kardiale Arrhythmien.

A relationship between behavioural factors and cardiac arrhythmogenesis in humans has been described. Three sets of conditions contribute to the occurrence of arrhythmias: myocardial electrical instability, most often due to coronary artery disease; an acute triggering event, frequently related to mental stress; and a chronic, pervasive, and intense psychological state, often including depression and hopelessness. The autonomic nervous system plays an important role in the occurrence of cardiac arrhythmias and it is well documented that mood alterations as mental stress and depression influence cardiac autonomic balance. There is an increasing body of evidence that patients with the greatest changes in cardiac neural regulation with decreased parasympathetic tone coupled with increased sympathetic activity are at the greatest risk for developing fatal ventricular arrhythmias. These patients have a reduced heart rate variability, increased QT-dispersion and a decreased baroreceptor sensitivity. The influence of stress and depression on the autonomic nervous system and the impact on the occurrence of both atrial and ventricular arrhythmias is being discussed.

[ICD therapy in patients with coronary artery disease--incidence of adequate interventions]. / ICD-therapie bei Patienten mit koronarer Herzkrankheit--Inzidenz adäquater Interventionen.

BACKGROUND: The Implantable Cardioverter/Defibrillator (ICD) represents the therapy of choice for patients at risk of malignant ventricular arrhythmias. The survival benefit of the ICD vs antiarrhythmic therapy in patients with coronary artery disease and ventricular tachycardia has been proven. Recently, the ICD therapy has also been established for primary prevention in high risk patients. We report about the incidence of adequate ICD therapies in patients with coronary artery disease, who underwent ICD implantation at the University Hospital Zurich. METHODS: 104 consecutive patients (97 men, 7 women, mean age of 67 +/- 10 years) with coronary artery disease, who underwent ICD implantation in accordance with the AHA/ACC/NASPE guidelines between January 2000 and July 2003 were included in the study. Follow-up was performed every three to six months, when all ICD therapies were documented. This documentation was used for analysis of adequate or inadequate ICD therapies. RESULTS: The mean follow-up time was 383 +/- 195 days. The time to the first adequate therapy was 201 +/- 283 days. The cumulative incidence for the first adequate therapy was 21% at six months, 39% at two years and 59% at four years. In 64% of patients, who experienced adequate ICD therapies, antitachycardia pacing (ATP) and in 36% an initial shock was delivered. ATP was successful in 83% of adequately delivered episodes. In the follow-up period 12 patients died. CONCLUSION: The benefit of the ICD was apparent in patients at risk for ventricular arrhythmias and coronary artery disease after a relatively short period of time, which underlines the important role of the ICD in primary and secondary prevention.

The effect of unilateral vasectomy on testosterone and testicular parameters in the adult male African giant rat (Cricetomys gambianus).

BACKGROUND: The effects of vasectomy on spermatogenesis and reproductive parameters are recognized to be specie-dependent with marked differences in levels of perturbations observed. OBJECTIVES: To assess the impact of unilateral vasectomy on testosterone level and other testicular parameters in the male African giant rat (AGR) (Cricetomys gambianus). METHODS: Sixteen adult male AGRs weighing 500-1300 g were recruited for the experiment. Animals were randomly divided into three experimental groups (1-3) and one control (sham operated) group with four rats per group. Experimental vasectomy was done by carefully ligating the vas deferens of the right testis of all the experimental groups (1, 2, and 3) and animals were allowed either 8, 6 and 2 weeks respectively before sacrifice. Sham-operated animals served as the control. Blood samples were collected and assayed for testosterone while testicular tissue was further processed for seminal fluid and histo-pathological analyses. RESULTS: Spermatogenic parameters indicate a pattern of decline in sperm count and motility between the experimental groups and the control and azoospermia in the eight-week group. Histological alterations were marked by atrophy of seminiferous tubules which was proportional to the duration of vasectomy. Serum testosterone levels were significantly reduced at eight weeks. There was no statistically significant difference between sperm counts of right and left testes except for group 3. Results suggest that unilateral vasectomy of the AGR may have negative impact on the contralateral testis in the male African giant rat. CONCLUSION: These preliminary results reveal that unilateral vasectomy in the AGR may result in perturbations of the histo-architecture of the testes with possible decline in function.