Right ventricular implantable cardioverter defibrillator lead implantation through a persistent left superior vena cava

A 60-year-old woman required implantation of an ICD because of a hypotensive ventricular tachycardia refractory to four different antiarrhythmic drugs. Preoperative diagnostics revealed a persistent left SVC as the only major venous return from the upper part of the body to the heart. Under local anesthesia, a tripolar lead was advanced through the left SVC into the right ventricular apex. Following successful testing, an active can ICD device was implanted, which is functioning well during a follow-up period of 9 months.     

Comparison of three cardioverter defibrillator implantation techniques: initial results with transvenous pectoral implantation

A total of 121 patients underwent epicardial (n = 32), transvenous abdominal (n = 30), and transvenous pectoral (n = 59) ICD implants. Perioperative complications were defined as those occurring within 30 days after surgery. Hospital costs were calculated with $750 per day as a fixed charge. Duration of surgery was the time between the first skin incision and the last skin suture. Severe perioperative complications that were life-threatening or required surgical intervention occurred in the epicardial (6%) and transvenous (10%) abdominal groups, but not in the pectoral group. Perioperative mortality occurred only in the epicardial abdominal group, predominantly in patients with concomitant surgery (18%), and in 5% of patients without concomitant surgery. The duration of surgery was significantly shorter for transvenous pectoral implantation (58 +/- 15 min, P < 0.05) compared to transvenous abdominal implantation (115 +/- 38 min). Epicardial abdominal ICD implantation had the longest procedure time (154 +/- 31 min). The postimplant hospital length of stay was significantly shorter for pectoral implantation (5 +/- 3 days, P < 0.05) compared to transvenous (13 +/- 5) and epicardial (19 +/- 5) abdominal implantation. Total hospitalization costs significantly decreased in the pectoral implantation group ($4,068 +/- $2,099 for the pectoral group vs $14,887 +/- $4,415 and $9,975 +/- $3,657 for the epicardial and the transvenous abdominal group, respectively, P < 0.05). These initial results demonstrate the advantage of transvenous pectoral ICD implantation in terms of perioperative complications, procedure time, hospital length of stay, and hospitalization costs.     

Admission to an intensive care unit after transvenous implantable cardioverter defibrillator implantation: analysis of risk factors

The endocrine abnormality that causes slipped capital femoral epiphysis (SCFE) has not been revealed. Recent studies have shown that parathyroid hormone (PTH) and 1,25-dihydroxyvitamin D [1,25-(OH)2D] are involved in growth-plate chondrogenesis and matrix mineralization. Thus we examined in 13 patients with SCFE the serum levels of three immunoreactive forms of PTH (iPTH): the whole peptide [(1-84)PTH], the fragment containing the COOH-terminal portion (C-PTH), and the midportion (M-PTH). Additionally, serum levels of 25-hydroxyvitamin D [25-(OH)D] and 1,25-(OH)2D were measured. We found that the levels of M-PTH were significantly lower than those of controls, whereas levels of C-PTH and (1-84)PTH were not significantly different from those of controls. Similarly, levels of 1,25-(OH)2D were also significantly lower than control levels. In patients with initially low levels of M-PTH and 1,25-(OH)2D in whom the levels were monitored over a period, all levels returned to normal within a year after the onset of disease. The deficiency of M-PTH or 1,25-(OH)2D during the growth spurt could result in SCFE, although in this study, we cannot deny the possibility that the slippage may cause the deficiency.     

Late complications in patients with pectoral defibrillator implants with transvenous defibrillator lead systems: high incidence of insulation breakdown

As the majority of ICDs with transvenous leads are now implanted in the pectoral region, complications associated with the technique are being identified. To determine the incidence of lead complications in patients with transvenous defibrillator leads and ICDs implanted in the pectoral region, 132 unselected consecutive patients with transvenous defibrillator leads had ICDs implanted in the pectoral region. Three lead systems were used: (1) lead system 1 (45 patients) consisted of a transvenous pacing sensing lead and a superior vena cava coil with a submuscular patch used for defibrillation; (2) lead system 2 (36 patients) utilized a CPI Endotak lead system; and (3) lead system 3 (51 patients) utilized a Medtronic Transvene lead system. Patients were followed for 3-54 months (cumulative 2,269, mean 18 months). The average duration of follow-up with the three systems was 32, 12 and 11 months, respectively. At 30 months follow-up, all three lead systems had a low incidence of complications. However, there was a 13% overall incidence (45% actuarial incidence) of erosion of the insulation of the pacing sensing lead of system 1 at 50 months of follow-up. All lead complications were seen in patients with ICDs whose weights were > 195 g and volumes > 115 cc. The erosion was probably a consequence of the pressure by the large ICD against the lead in the pectoral pocket. Follow-up with lead systems 2 and 3 is relatively short (average 12 months) but no lead erosions were seen. Pectoral implantation of ICDs with long transvenous leads and large generators is associated with a moderate risk of late complications in the form of insulation breaks caused by pressure of the generator against the leads. The use of less redundant leads coupled with smaller ICDs will probably eliminate this complication.     

Immediate reproducibility of upper limit of vulnerability measurements in patients undergoing transvenous implantable cardioverter defibrillator implantation

BACKGROUND: Asynchronous electrical activation, induced by ventricular pacing, causes regional differences in workload, which is lower in early- than in late-activated regions. Because the myocardium usually adapts its mass and structure to altered workload, we investigated whether ventricular pacing leads to inhomogeneous hypertrophy and whether such adaptation, if any, affects global left ventricular (LV) pump function. METHODS AND RESULTS: Eight dogs were paced at physiological heart rate for 6 months (AV sequential, AV interval 25 ms, ventricular electrode at the base of the LV free wall). Five dogs were sham operated and served as controls. Ventricular pacing increased QRS duration from 47.2+/-10.6 to 113+/-16.5 ms acutely and to 133.8+/-25.2 ms after 6 months. Two-dimensional echocardiographic measurements showed that LV cavity and wall volume increased significantly by 27+/-15% and 15+/-17%, respectively. The early-activated LV free wall became significantly (17+/-17%) thinner, whereas the late-activated septum thickened significantly (23+/-12%). Calculated sector volume did not change in the LV free wall but increased significantly in the septum by 39+/-13%. In paced animals, cardiomyocyte diameter was significantly (18+/-7%) larger in septum than in LV free wall, whereas myocardial collagen fraction was unchanged in both areas. LV pressure-volume analysis showed that ventricular pacing reduced LV function to a similar extent after 15 minutes and 6 months of pacing. CONCLUSIONS: Asynchronous activation induces asymmetrical hypertrophy and LV dilatation. Cardiac pump function is not affected by the adaptational processes. These data indicate that local cardiac load regulates local cardiac mass of both myocytes and collagen.     

Arterial embolism complicating implantable cardioverter defibrillator shocks with normal ventricular function

A 69-year-old man developed an embolus to his right femoral artery 24 h following the insertion of an implantable cardioverter defibrillator (ICD), with multiple shocks administered in the early postoperative period. He had nonobstructive hypertrophic cardiomyopathy with normal left ventricular function and no evidence of left atrial or ventricular thrombus seen on pre- or postoperative transthoracic echocardiography. There was no evidence of atrial fibrillation documented before or after implantation of the device. He had no other known risk factors for thromboembolic disease. Thromboembolic phenomena as a complication of ICD use have been described but arterial emboli believed related to ICD shocks have not been reported in patients without impaired systolic function.     

Cardiomyoplasty combined with implantation of a cardioverter defibrillator

Congenital absence of the scaphoid without associated thumb or radial hypoplasia is a rare condition. This report is the third case presented in the literature of this condition. The case presented is of a patient who presented initially with wrist pain. Radiographs revealed a congenitally absent scaphoid and examination revealed no evidence of thumb hypoplasia. A brief review of the literature on congenital absence of the scaphoid is discussed.     

Comparison of metoprolol and sotalol in preventing ventricular tachyarrhythmias after the implantation of a cardioverter/defibrillator

The purpose of this prospective study was to evaluate, on an intention-to-treat basis, the efficacy of d,l-sotalol and metoprolol with regards to the recurrence of arrhythmic events after implantable cardioverter defibrillator (ICD) implantation. After ICD implantation, 70 patients were randomly assigned to treatment with either metoprolol (mean dosage 104+/-37 mg/day in 35 patients) or d,l-sotalol (mean dosage 242+/-109 mg/day in 35 patients). During follow up ventricular tachycardia (VT), fast VT, and ventricular fibrillation (VF) episodes were calculated. Metoprolol treatment led to a marked reduction in the recurrence of arrhythmic events. Actuarial rates for absence of VT recurrence at 1 and 2 years were significantly higher in the metoprolol group compared with the d,l-sotalol group (83% and 80% vs 57% and 51%, respectively, p=0.016). The actuarial rates for absence of fast VT or VF were 80% in the metoprolol group compared with 46% in the d,l-sotalol group (p=0.002). During a follow up of 26+/-16 months, there were 3 deaths in the metoprolol group compared with 6 deaths in the d,l-sotalol group. Actuarial rates of overall survival were not significantly different in the 2 groups (91% vs 83%, p=0.287). In this prospective, randomized, controlled study the recurrence rate of ventricular tachyarrhythmias in patients treated with metoprolol was lower than in patients treated by d,l-sotolol.     

Use of atrial and ventricular electrograms from a dual chamber implantable cardioverter defibrillator to elucidate a complex dysrhythmia

Stored intracardiac electrograms provided by third-generation ICDs have proved their use in the analysis of the mechanism of tachydysrhythmic events. There are cases in which the analysis of ventricular electrograms is insufficient for the elucidation of certain dysrhythmias. The availability of atrial electrograms provided by dual chamber ICDs improves the diagnostic capability of electrogram analysis and could prove most useful especially in complex dysrhythmias.     

Cardiomyoplasty after implantation of a pacemaker and cardioverter/defibrillator

Presently, a combination of two surgical methods improves the survival of patients with advanced ventricular dysfunction: implantable cardioverter/defibrillator implantation (which prevents sudden cardiac death) and cardiomyoplasty (which prevents further dilatation of the heart and provides additional cardiac assistance). We report the clinical course of a patient who had cardiomyoplasty after cardioverter/defibrillator implantation and pacemaker insertion. It is a rare case in which three different devices cardioverter/defibrillator, pacemaker, and cardiomyostimulator) are functioning together without crosstalk.     

Extraction of pacemaker and implantable cardioverter defibrillator leads

To determine the mechanisms by which human immunodeficiency virus type 1 (HIV-1) crosses the placenta into the fetal blood, 12 matched samples of serial maternal blood, term placentas, and infant blood obtained from a cohort of pregnant women in Cameroon identified as predominantly infected by subtype A viruses were studied. HIV-1 env sequences were detected by polymerase chain reaction (PCR) in both chorionic villi and enriched trophoblastic cells of all 12 placentas but at variable rates of detection. Heteroduplex mobility assay analysis showed the presence of multiple HIV-1 env quasispecies in sequential maternal peripheral blood mononuclear cell samples, but only a small number of env variants were found in chorionic villi and enriched trophoblastic cells. These data indicate that HIV-1 env sequences are always present in term placentas of seropositive women, contrasting with the low frequency at which infection is diagnosed by PCR in neonates with tat, gag, and env primers. Maternal HIV-1 variants appear to undergo a strong negative selection by different cell populations within the placental villi.     

An overview of the fifth-generation implantable cardioverter defibrillator

It has been established that treatment with an implantable cardioverter is effective for life-threatening arrhythmia including ventricular tachycardia (VT) and ventricular fibrillation (VF). Although most third and fourth-generation implantable cardioverter defibrillator (ICD) models are effective for the treatment of VT and VF, they often misinterpret supraventricular tachycardia (SVT), and the incidence of inappropriate therapy delivered is as high as 20 to 40%. To solve this clinical problem, the dual-chamber ICD was developed. According to the current reports on a study of the main fifth-generation ICD models that have been clinically used, 86 to 100% sensitivity regarding discrimination was obtained. In addition, the sensitivity for delivering appropriate therapy for VT was 97 to 100%. Since the indications for ICD therapy are being expanded, additional improvement of the device and adequate patient selection are recommended.     

A review of the implantable cardioverter defibrillator trials

Intravenous immunoglobulin is now used in a wide range of neurological conditions. However, side effects are relatively common, treatment is expensive and sustained benefit unusual without repeated administration. This article aims to provide clinicians with an overview of the potential benefits and drawbacks of intravenous immunoglobulin in neurological practice and concludes with suggested guidelines for its use in adults.     

Early cardioverter defibrillator infection: value of indium-111 leukocyte imaging

In the early postoperative period, it may be difficult to diagnose an infected implantable cardioverter-defibrillator system using anatomic imaging modalities such as computed tomography alone. We describe a case that illustrates the complementary physiologic role of indium-111-labeled leukocyte scintigraphy in identifying and defining the extent of early postoperative implantable cardioverter-defibrillator infection.     

Nonthoracotomy implantation of cardioverter defibrillators: preliminary experience with a defibrillation lead placed at the right ventricular outflow tract

Although morbidity and mortality associated with defibrillator implantation using a nonthoracotomy approach have decreased as compared with a thoracotomy approach, defibrillation thresholds have been higher and fewer patients satisfied implant criteria. It may be possible to improve on the success of nonthoracotomy defibrillator implantation by the placement of a right ventricular (RV) outflow defibrillation lead. Implantable cardioverter defibrillator implantation data of 30 consecutive patients with clinical VT or VF were reviewed. Three defibrillation leads were routinely used. When either pacing threshold at the RV apex was inadequate (n = 2) or 18-J shocks were not successful in terminating VF in 3 of 4 trials (n = 8), the RV apex lead was positioned to the RV outflow tract attaching to the septum. Defibrillation testing was first performed with the RV apex lead in combination with CS, SVC, and/or subcutaneous leads. Twenty patients satisfied implant criteria with a defibrillation threshold of 13.5 +/- 3.6 J. In 7 of the 10 patients, whose RV lead was repositioned to the RV outflow tract, this lead in combination with SVC, CS, or subcutaneous leads produced successful defibrillation at < or = 18 J or in 3 of 4 trials. This approach improved the overall success of nonthoracotomy implantation of defibrillators from 69% to 90%. After a follow-up of 27 +/- 6 months, there was no dislodgment of the RV outflow tract defibrillation leads. CONCLUSIONS: This article reports the preliminary observation that placement of defibrillation leads to the RV outflow tract in humans was possible and without dislodgment. RV outflow tract offers an alternative for placement of defibrillation leads, which may improve on the success of nonthoracotomy defibrillator implantation.     

Postshock sensing performance in transvenous defibrillation lead systems: analysis of detection and redetection of ventricular fibrillation

INTRODUCTION: The sensing performance of transvenous lead systems may be adversely affected by the delivery of high-energy shocks. This may be due to the proximity of the sensing and energy-delivery electrodes on transvenous leads. METHODS AND RESULTS: The time required for detection of ventricular fibrillation and redetection after a failed first shock was compared in 93 patients with five different lead system-pulse generator combinations: Cadence--Endotak 60 series, Ventak P--Endotak 60 series, Jewel--Transvene, Cadence--TVL, and Cadence--Transvene. A total of 418 successful and 204 failed first shocks were delivered during induced ventricular fibrillation. Redetection times (RED) were consistently shorter than detection times (DET) in the Jewel-Transvene (RED minus DET: -1.9 +/- 0.8 sec, P < 0.0001), the Cadence-TVL (-1.6 +/- 1.0 sec, P < 0.0001), and the Cadence-Transvene combinations (-2.0 +/- 0.9 sec, P < 0.0004). Redetection times were not significantly different than detection times in the Cadence-Endotak combination (0.9 +/- 3.1 sec; P = 0.09). Redetection times were significantly longer than detection times in the Ventak-Endotak combination (1.2 +/- 2.3 sec; P = 0.034). Prolonged individual redetection episodes (> 8.2 sec) were observed in the Cadence-Endotak (7 [10%] of 73 episodes) and the Ventak-Endotak (4 [10%] of 39 episodes), but not in the Jewel-Transvene, the Cadence-TVL, and the Cadence-Transvene combinations. CONCLUSIONS: Redetection of ventricular fibrillation may be delayed in some transvenous lead-pulse generator combinations. Successful redetection of ventricular fibrillation following a failed first shock should be demonstrated prior to hospital discharge of patients with implantable defibrillators.     

Effect of extracorporeal shock wave lithotripsy on implantable cardioverter defibrillator

Extracorporeal shock wave lithotripsy (ESWL) is frequently used for nephrolithiasis of the upper urinary tract. Because of the powerful shock wave and electromechanical forces created, this therapy has been contraindicated in the patient with an implantable cardioverter defibrillator (ICD). To determine whether or not ESWL affects ICD devices, we subjected ten devices to a full course of ESWL. The devices were then returned to the manufacturer to undergo bench analysis, which revealed no abnormalities in function. Additionally, one device was placed in the pathway of the shock wave, resulting in a discharge of the device despite a frequency of ESWL of 100 shocks/min (well below the rate cutoff of that device). Manufacturer analysis of this device, likewise, revealed no abnormalities even though the device had been exposed to the focal point of the shock wave. We conclude that contralateral ESWL is not contraindicated for the patient with an ICD. We do, however, recommend a post-procedure evaluation to ensure appropriate function of the ICD.     

Sudden death as a presenting symptom of hypertrophic cardiomyopathy: treatment with an implantable cardioverter defibrillator

Aborted sudden death as the presenting manifestation of hypertrophic cardiomyopathy in a 14-year-old child is reported. Documented ventricular fibrillation was the cause of cardiac arrest. No ventricular arrhythmia was induced during programmed electrical stimulation. An implantable cardioverter-defibrillator was indicated. As the patient had a family history of myocardial disease, he had undergone a cardiovascular evaluation 4 years before the major event, and was found normal. It is suggested that normal physical examination, ECG, echocardiogram should not rule out the diagnosis of hypertrophic cardiomyopathy when a family history is present. Left ventricular hypertrophy may develop during childhood in patients with hypertrophic cardiomyopathy.     

Arteriovenous malformation: a 22-year angiographic follow-up

A case is reported of an unoperated giant arteriovenous malformation with a progressive deterioration ending in a severe dementia and invalidism. Angiographic documentation is over a 22 year interval. The presentation, diagnosis and treatment of this disease are discussed. It is concluded that early surgical intervention should have a primary role in the management of giant arteriovenous malformation.     

Influence of the implantable cardioverter defibrillator on survival: retrospective studies and prospective trials

Frequent losses of heterozygosity observed at several chromosomal loci in primary lung cancers have indicated the existence of several tumor suppressor genes associated with this type of cancer. We have examined loss of heterozygosity on chromosomal arm 8p in 49 cases of non-small cell lung carcinoma, using 14 restriction fragment length polymorphism markers. Of 42 cases informative with at least one marker, 21 showed allelic loss, including 15 of 32 adenocarcinomas and 5 of 9 squamous cell carcinomas. The frequency of allelic loss on 8p was similar at all clinical stages. Deletion mapping defined a single common region of deletion in these tumors within an 8 cM interval at 8p21.3-p22 flanked by the loci defined by cMSR-32 and cC18-245.