Preexcitation in Hypertrophic Cardiomyopathy: A Case of a Fasciculoventricular Mahaim Fiber

STELLBRINK, C., et al .: Preexcitation in Hypertrophic Cardiomyopathy: A Case of a Fasciculoventricular Mahaim Fiber . A patient with hypertrophic cardiomyopathy (HCM) who presented with preexcitation pattern on the surface ECG suggestive of the Wolff-Parkinson-White (WPW) syndrome is described. Intracardiac electrophysiological study revealed a fixed anomalous QRS complex and a short fixed His-ventricular interval indicating a fasciculoventricular Mahaim fiber. As this specific form of accessory connection does not cause reentrant tachycardias, no treatment was required. It is important to distinguish this entity from atriofascicular or nodoventricular Mahaim fibers or the WPW syndrome in patients with HCM showing a preexcitation pattern in the surface ECG, as these may cause life-threatening arrhythmias in this patient population.     

Liposomal 1,25 (OH)2 vitamin D3 compounds block proliferation and induce differentiation in myelomonocytic leukaemia cells

The vitamin D₃ derived hormone 1,25 (OH)₂ vitamin D₃ (1,25 D₃) is able to induce growth arrest and differentiation in myelomonocytic leukaemia cells. In order to allow for specific delivery to leukaemic cells the lipophilic compound was incorporated into the lipid membranes of liposomes. Liposomal 1,25 D₃ reduced proliferation as measured by ³H-thymidine incorporation in HL60 leukaemia cells by up to 60%. When liposomes were prepared at different concentrations of 1,25 D₃ 65% inhibition was achieved at 48 n M . The MC 1288 stereoisomer of 1,25 D₃ was more potent and had the same activity at 48 n M .
The effect of the liposomal compounds was specific to myeloid cells as they reduced proliferation in myelomonocytic HL60, monoblastic U937 and monocytic Mono Mac 6 cells but not in the T-cell lines Jurkat and Molt 4.
The antiproliferative effect of liposomal 1,25 D₃ was associated with an induction of differentiation since treated HL60 cells showed a monocytic morphology, increased expression of CD14 and decreased expression of CD33.
When peripheral blood leukaemic cells from M4 and M5 acute myeloid leukaemia (AML) patients were admixed with liposomal compounds an antiproliferative effect was seen in all five cases, including the two cases where free compounds led to enhanced growth. Liposomal delivery of 1,25 (OH)₂ vitamin D₃ may offer a novel approach to treatment of myelomonocytic leukaemia.     

Transcoronary Venous Radiofrequency Catheter Ablation of Ventricular Tachycardia

Coronary Venous Ablation of VT. Ventricular tachycardias in coronary artery disease arise mostly from endocardial sites. However, little is known about the site of origin in other diseases. We present the case of an incessant, adenosine-sensitive ventricular tachycardia arising from the lateral wall of the left ventricle in a patient with mildly reduced left ventricular function. Intracardiac mapping suggested an epicardial origin, and the tachycardia was successfully ablated from a coronary sinus branch. After ablation, left ventricular function returned to normal. Transcoronary venous radiofrequency catheter ablation is a new approach for the treatment of ventricular tachycardia. Its value in the management of other types of ventricular tachycardia has yet to he determined.     

Vecuronium titration for muscle relaxation in myotonic dystrophy

A 14-year-old boy with pronounced myotonic dystrophy and cardiac malformation had a normal ED₉₅ (53 μg·kg^?1) of vecuronium, whereas the recovery index (25-75% twitch recovery) was three times as long as in the absence of neuromuscular disease. We conclude that in young patients with dystrophic muscle disease individual titration of the muscle relaxant with the aid of a nerve stimulator does not preclude a considerable delay in the recovery of neuromuscular transmission.     

The impact of performance uncertainty on the postimperative negative variation

In a delayed matching-to-sample task, the impact of clear or ambiguous go versus clear no-go signals on the post-imperative negative variation (PINV) was examined in 11 patients with a chronic schizophrenic disorder (DSM-III-R) and in a control group of 13 healthy subjects matched to the patient sample by age, sex, and education. Size and spatial position of a visual S2 had to be matched to one of two visual patterns in the S1 presented 4 s earlier. In 96 trials, the S2 was identical in size with one of the two patterns of S1 (clear matching). These trials varied pseudorandomly, with 60 trials in which the S2 was of intermediate size. On a randomly interspersed additional 48 trials, an S2 differing in color and shape signaled no-go. The electroencephalogram was recorded from Fz, Cz, Pz, F3, F4, C3, C4, P3, and P4. Although groups did not differ in contingent negative variation amplitude the PINV was generally more pronounced in patients than in controls. In both groups, ambiguity of the to-be-matched S2 produced larger PINV amplitudes; the no-go signal elicited only a small PINV. Differential effects of ambiguity and no-go on PINV amplitude and its scalp distribution suggest that “performance” and “action” uncertainty contribute to PINV generation and that thresholds for both effects are reduced in schizophrenics.     

Reforming health care for the elderly--the example of Vorarlberg

Vorarlberg—Austria'S most western province with a populationof about 325 000—has always implemented forms of socialpolicy in which the principles of subsidiarity and solidarityplay an important role. This is reflected in the structure ofthe organizations traditionally providing social services aswell as in the more recent programme.s the government has developedfor social policy. This paper discusses two cases in point: the private associationsfor home care (Krankenpflegerverbände)—which nowexist in 65 Vorarlberg communities and cover 85% of the populationin the province—offering nursing services at home to membersor to persons who are willing to join the organization whenthey need care, and the new organizational model, called GesunderLebensraum Vorarlberg (GLV), which is successfully operatingin a few pilot communities. GLV has spawned umbrella organizations,run by volunteers, and offering a variety of social servicesrelevant to the elderly, for example visiting services or neighbourhoodhelp in case of emergencies. The volunteers get organizationalhelp from a profit-making firm financed by the government. The Vorarlberg models can be interpreted as a step towards demedicalizationand dein.stitutionalization of health care for the elderly.Nevertheless, they also show the problems that arise when professionalsand volunteers must cooperate. The models may lead to savingsfor the governments involved, although details are still subjectto future empirical investigations.     

Increased Apoptotic Cell Death in the Neointima after Stent-Based Vascular Irradiation: Role of Radiation-Induced Apoptosis for Restenosis Reduction

Background: Restenosis after stent implantation is a common problem faced today by interventional cardiologists. It is primarily caused by excessive neointimal growth. Early clinical studies showed substantial reductions of neointimal volumes within bodies of³²P radioactive coronary stents. Radiotherapy induces programmed cell death (apoptosis) in tumors but there is still debate whether irradiation causes apoptosis in arteries. Methods: We compared the time course of neointimal apoptosis after implanting 7-mm long ³²P radioactive slotted tubular stents in rabbit iliac arteries. The stents were homogeneously ion-implanted with ³²P at activity levels of 0.5 and 6 μCi. These stents produce continuous beta-particle emission at very low dose rates. Neointima formation was compared with nonradioactive stents by histomorphometry after 1, 4, and 12 weeks. Apoptosis was detected using the terminal deoxynucleotidyl transferase mediated dUTP nick end labeling (TUNEL) assay method and transmission electron microscopy. Results: At an early follow-up of 1 week after stent implantation, no changes in neointimal apoptosis were found. The ³²P stents at activities of 6 μCi, but not of 0.5 μCi, reduced neointimal crosssectional areas and cell numbers compared with control stents after 4 and 12 weeks. Apoptosis in the neointima increased after 4 weeks and was substantially elevated 12 weeks after implantation of 6 μCi ³²P stents compared with 0.5 μCi and control stents (16% vs 6% and 3%, P < 0.01 for 6 vs 0.5 μCi and control stents, respectively). Conclusions: In this study, a dose dependent decrease in neointimal thickening and cell density within ³²P beta-particle emitting stents was associated with an increased frequency of apoptosis. This increase in apoptosis occurred late in the time course of vascular healing after the implantation of ³²P beta-particle emitting stents. Apoptosis seems to be involved in the mechanisms by which stent-based vascular irradiation reduces neointimal hyperplasia.     

Early Postinterventional Stent Stenosis of a Ductus Stent Implanted for Palliation in a Newborn with Pulmonary Atresia with Intact Ventricular Septum: Successful Management with Bailout Stenting

A newborn with pulmonary atresia with intact ventricular septum (PA-IVS) was treated with radiofrequency current perforation of the atretic pulmonary valve. As the right ventricle was hypoplastic (z-value of the tricuspid valve: —4) the arterial duct was stented with a Gianturco-Roubin GR II stent. Early postinterventionally, the patient became cyunotic and compromised blood flow across the stented ductus arteriosus despite adequate stent position was detected echographically. The newborn was treated successfully with the implantation of a Palmaz stent (Johnson & Johnson Interventional Systems, Warren, NJ, USA) into the obstructed Gianturco-Roubin GR II stent. The Gianturco-Roubin GR II stents might be associated with the risk of early stent stenosis after implantation in actively contracting tissues like the ductus arteriosus. In patients with early stent stenosis after ductal stenting, bailout implantation of a subsequent stent can be performed. Transcatheter procedures can be effective means for therapy of PA-IVS . (J Interven Cardiol 2000;13:39–44)