Electrocardiographically Documented Unnecessary, Spontaneous Shocks in 241 Patients With Implantable Cardioverter Defibrillators

The incidence and cause of electrocardiographically documented spontaneous implantuble Cardioverter defibrillator (ICD) discharges for a rhythm other than ventricular tachycardia (VT) or fibrillation (VF) (unnecessary shocks) were determined in 241 patients who underwent ICD implantation between March 1983 and November 1991. During follow-up of 24 ± 20 months, 54 of 241 patients (22%) received a total of 132 unnecessary ICD shocks confirmed by Holler or telemetry monitoring or stored electrograms (Egs) from the ICD. The rhythm preceding these unnecessary ICD shocks was atrial fibrillation in 30 patients, sinus or supraventricular tachycardia (SVT) in 11 patients, antitachycardia pacing triggered by atrial fibrillation or SVT resulting in VT in 5 patients, nonsustained VT in 3 patients, and normal sinus or pacemaker rhythm in 10 patients. Unnecessary ICD discharges occurred most frequently during the first week after implantation or generator replacement (18 of 54 patients [33%]). Unnecessary ICD discharges could be documented more often by stored Egs in patients with devices with Eg storage capability (Ventritex Cadence(tm), 19 of 54 patients [35%]) than by Holter or telemetry monitoring in patients with devices without Eg storage capabilities (34 of 193 patients [18%], P < 0.01), despite a shorter mean follow-up duration of 14 ± 9 months versus 26 ± 21 months, respectively. Only six of 54 patients (11%) in whom unnecessary ICD discharges occurred had recurrent unnecessary shocks during 22 ± 20 months of follow-up after treatment directed at the cause of the first episode or device reprogramming to preclude non-VT rhythm detection. In conclusion, unnecessary ICD shocks are a frequent complication of ICD therapy occurring in at least 22% of patients. The cause of these shocks is most frequently atrial fibrillation with a rapid ventricular response. The availability of Eg storage capabilities facilitates the diagnosis of the electrical event precipitating inappropriate ICD shocks. Diagnosis of the cause of unnecessary shocks allows for the institution of therapy that may reduce the risk for subsequent events.     

Course of Symptoms and Spontaneous ECG in Pacemaker Patients: A 5-Year Follow-up Study

We investigated the course of symptoms and the spontaneous ECG retrospectively in 308 patients who had received a pacemaker because of atrioventricular (AV) block (n = 115), sick sinus syndrome (SSS, n = 107), bradyarrhythmic atrial fibrillation (bradyarrhythmia, n = 51), carotid sinus syndrome (CSS, n = 16), complete bifascicular block associated with 1st degree AV block (n = 13) and with other indications (n = 6). The mean implantation time was 63 months. The clinical state of 93% of all patients improved after pacemaker implantation; their symptoms decreased markedly. Persisting syncopy in some patients with SSS, however, supports a restricted implantation policy. We rarely saw improved AV conduction in patients with AV block (11%). Furthermore, in patients with SSS, atrial fibrillation occurred significantly more often (35%) than in those with AV block (17%; P less than 0.01). Only 3% of patients with SSS developed 2nd and 3rd degree AV block within the observation period. In all patients with initial bifascicular block and additional 1st degree AV block, pacing prevented further syncopal attacks; four of them showed 3rd degree AV block at control, indicating that pacemaker implantation is mandatory in symptomatic patients with bifascicular disease and 1st degree AV block.     

Therapy of Cardiac Device Pocket Infections with Vacuum‐Assisted Wound Closure—Long‐Term Follow‐Up

Background: Cardiac device infections are serious complications that require aggressive treatment strategies, including interventional or surgical lead extraction. Methods: Here we describe the long‐time follow‐up of vacuum‐assisted closure (V.A.C.) treatment in five patients with local cardiac device infection (LDI). In these patients the device was removed, the electrodes were shortened, and a V.A.C. treatment was applied. The primary endpoint was defined as time to re‐LDI. Results: Three patients had LDI of a pacemaker pocket, whereas two presented with an infection of their ICD pocket. The V.A.C. treatment was applied for 34.4 ± 17.9 days. The mean hospitalization time was 38.6 ± 19.2 days. The follow‐up period was assessed for 34.6 ± 19.2 months. Only one patient developed re‐LDI, 69 days after removal of the device. The other four patients did not show any signs of reinfection during the follow‐up period. None of the five patients sustained serious adverse events. Conclusions: V.A.C. treatment may be an option for selected patients with LDI who refuse a laser‐guided lead extraction or surgical removal of the electrodes as the primary therapy. (PACE 2012; 35:1217–1221)     

The fusion of TEL and ABL in human acute lymphoblastic leukaemia is a rare event

We have recently identified a common ALL patient which harboured a chromosomal fusion between the TEL gene on chromosome 12 and the ABL gene on chromosome 9. We designed an RT-PCR assay to screen 186 adult ALL and 30 childhood ALL patients for this novel translocation. We were unable to identify any additional cases with a TEL/ABL fusion product.     

Clinical Applicability of in vivo Reflectance Confocal Microscopy for the Diagnosis of Actinic Keratoses

BACKGROUND In vivo reflectance confocal microscopy (RCM) has been used for evaluation of the morphologic features of nonmelanoma skin cancer. The application of RCM for diagnosis of basal cell carcinoma has been reported; however, the evaluation of actinic keratoses (AKs) has only been the subject of preliminary studies.
STUDY GOAL The goal of this study was to evaluate the applicability of RCM in the diagnosis of AK in correlation with routine histology.
MATERIALS AND METHODS Forty-four Caucasians with a minimum of one AK participated in this study. Evaluation consisted of clinical examination, RCM, and routine histology, including a total of 46 AKs in the final analysis. Ten normal skin sites served as controls. RCM features of AK included parakeratosis, architectural disarray, and keratinocyte pleomorphism. Following blinded evaluations, sensitivity/specificity, kappa analysis, and Spearman's correlation were performed on all parameters.
RESULTS Sensitivity/specificity values of RCM features ranged from 80% to 98.6%. The presence of architectural disarray and cellular pleomorphism appeared to be the best predictor of AK.
CONCLUSION In summary, RCM may be a promising technology for the noninvasive detection of AK and as adjunct tool to clinical diagnosis and monitoring. However, the preliminary nature of this study warrants further investigations.     

Angiographic and Histologic Course after Implantation of Balloon Expandable Intravascular Stents in Miniswine Coronary Arteries: Short- and Mid-Term Observations

Sixteen balloon expandable Medtronic Wiktor tantalum stents were implanted in the major coronary arteries of six minipigs, which were maintained on a normal diet and given 500 mg aspirin per day. Angiographic and histologic examinations were performed 6 and 26 weeks after implantation. Angiographically reviewed, stenting increased the inner diameter of the coronary arteries from 2.61 ± 0.44 to 3.02 ± 0.34 mm (n = 16, P ≤ 0.001). Six weeks later, this value was reduced from 2.98 ± 0.35 to 2.33 ± 0.46 mm (n = 9, P ≤ 0.05), and between 6 and 26 weeks, an increase from 2.17 ± 0.44 to 2.93 ± 0.40 mm occurred (n = 6, P ≤ 0.05). Histologic evaluation at 26 weeks after stent implantation revealed an increase of the cross-sectional area of the total vessel from 4.30 ± 1.09 to 5.50 ± 1.67 mm² (n = 9; P ≤ 0.01). This was due to widening of the total vessel and intimal proliferation, which amounted to 1.19 ± 0.46 mm² within the stented segment, as compared to 0.03 ± 0.03 mm² in control sections (P ≤ 0.01). The areas of free vessel lumen, media muscularis, and adventitia remained unchanged. In 15 of the 16 hislologically examined coronary arteries, the internal elastica was fractured at the site of stent implantation. Twelve stents had also penetrated through the external elastica without evidence of wall hemorrhage. Thirteen out of 16 stents were angiographically followed, of which 12 were patent at the final reangiography. In one animal, acute thrombosis of the stented vessel after guidewire induced coronary artery spasm caused chronic right heart failure due to right ventricular myocardial infarction. Sudden death occurred in another pig 2 hours after successful implantation of three grossly oversized stents (inner vessel diameter: 2.4 ± 0.2 mm, stent diameter 3.2 ± 0.5 mm). Autopsy revealed extensive dissections of the media with subsequent vessel occlusion. It is concluded that Medtronic Wiktor stents can be placed easily, even in more distal or curved coronary arteries. Despite antiaggregational medication, intimal proliferation is observed early after implantation, reaches a maximum at about 6 weeks, and is followed by a regression 26 weeks poststenting. At 26 weeks follow-up, the free vessel lumen at the stent site was not significantly reduced as compared to control segments. Proper adjustment of internal vessel diameter and stent diameter is necessary to prevent major dissections and thrombotic occlusions.