Case report: complex arrhythmia induced by noncompetitive atrial pacing algorithm of DDDR pacemaker

This report describes the occurrence of a repetitive nonreentrant ventriculoatrial (VA) synchronous rhythm precipitated by the noncompetitive atrial pacing algorithm of a Medtronic DDDR pacemaker. This algorithm delivers an atrial stimulus 300 ms after the detection of an atrial signal in the postventricular atrial refractory period of the pacemaker. In our patient, the atrial stimulus released by the algorithm was ineffectual because it encountered prolonged refractoriness of the atrial myocardium. This situation produced a repetitive nonreentrant VAl synchronous rhythm in the setting of retrograde VA conduction.

Evaluation of omeprazole in the treatment of reflux laryngitis: a prospective, placebo-controlled, randomized, double-blind study

OBJECTIVES

Proton-pump inhibitors are often recommended in the treatment of laryngitis secondary to gastric reflux. Despite prospective treatment studies reporting high efficacy, only one previous report has been placebo-controlled and blinded. The objective of this study was to determine the efficacy of omeprazole in treating proven reflux laryngitis.

STUDY DESIGN

Prospective, placebo-controlled, randomized, double-blind clinical trial.

METHODS

Fifty-three patients with one or more reflux laryngitis symptoms were recruited to undergo 24-hour dual-channel pH probe testing. Thirty patients with more than four episodes of laryngopharyngeal reflux were enrolled. By random assignment, 15 patients received 40 mg omeprazole twice a day and the other 15 received placebo for a period of 2 months. Symptoms (hoarseness, throat pain, lump in throat sensation, throat clearing, cough, excessive phlegm, dysphagia, odynophagia, and heartburn) and endoscopic laryngeal signs (erythema, edema, and mucus accumulation) were recorded initially, at 1 month, and 2 months.

RESULTS

In general, most symptom scores improved over time for both the omeprazole and placebo groups. Hoarseness, when patients begin with low hoarseness symptom scores, and throat clearing improved significantly more in patients on omeprazole than in those on placebo during the 2-month study. Throat pain, lump in throat sensation, excessive phlegm, difficulty swallowing, pain with swallowing, and heartburn showed improvement in both treatment arms, signifying the possibility of a placebo effect. Endoscopic laryngeal signs did not change significantly over the course of the study for either treatment group.

CONCLUSIONS

A placebo effect appears to exist in the treatment of reflux laryngitis. However, hoarseness, when initially scored low, and throat clearing resulting from reflux laryngitis are effectively treated by omeprazole.

Pacemaker repetitive nonreentrant ventriculoatrial synchronous rhythm. A review

Ventriculoatrial (VA) synchrony during dual chamber pacing can occur in any patient who has the ability to sustain repeated retrograde conduction. If the retrograde P wave is sensed, the result will be an endless loop tachycardia or repetitive reentrant VA synchrony. VA synchrony can also occur when a dual chamber pacemaker does not sense a retrograde P wave within the postventricular atrial refractory period. In this situation if the normally suprathreshold atrial stimulus at the end of the atrial escape interval is continually delivered when the atrial myocardium is physiologically refractory, the result will be a repetitive nonreentrant VA synchronous rhythm. Repetitive nonreentrant VA synchrony may produce unfavorable hemodynamic consequences and the pacemaker syndrome. It represents an example of functional atrial undersensing combined with functional loss of atrial capture. Management requires modification of the programmed settings of the pacemaker and utilization of certain algorithms designed for other functions but nevertheless effective in this situation.

Enhanced rate response algorithm for orthostatic compensation pacing

Upon orthostatic stress after a period of rest, the heart rate increases rapidly to maintain cardiac output and minimize the fall in arterial pressure. Pacemaker patients are often prone to a deficient response to orthostatic stress. This may cause lightheadedness and, in rare patients with autonomic dysfunction, syncope. To alleviate these undesirable consequences, an enhanced rate response algorithm was developed using an accelerometer. The pacemaker generates two signals from its accelerometer: instantaneous activity level (Act) and long-term change in activity level (ActVar). Low values of both Act and ActVar indicate a resting state. An increase in Act while ActVar remains low indicates the onset of motion after prolonged rest. Upon detecting this transition, the algorithm increases the pacing rate to a programmable orthostatic compensation rate for a programmable duration. A taped-on pacemaker with this algorithm was evaluated in three healthy women and two healthy men, 36 +/- 8 years of age. Electrocardiogram and ventricular pacing pulses were recorded by a 24-hour ambulatory system. Each trigger of the orthostatic compensation rate was verified against a > 10 beats/min increase in heart rate, a response classified as appropriate. The overall specificity of the algorithm among the five subjects was 78%. The nocturnal specificity (10 PM to 7 AM) was 98%, considerably higher than during daytime (72%). In conclusion, a pacing algorithm to alleviate orthostatic stress was developed, which was highly specific during the night hours.

Device eccentricity: postmagnet behavior of DDDR pacemakers with automatic threshold tracking

The normal pacing system function associated with the AutoCapture Pacing System algorithm triggered concern on the part of the clinical staff caring for the patient when the initiation of a threshold search sequence was detected during a transtelephonic follow-up evaluation. The analysis of the rhythm demonstrates that the behavior of the system is normal and consistent with the design of the AutoCapture algorithm. As a variety of new algorithms are introduced, similar unexpected but normal behaviors can be anticipated.

The effect of mechanoreceptor stimulation of the laryngopharynx on the oesophago-gastric junction

Stimulation of the pharynx by injection of minute amounts of water induces prolonged period of lower oesophageal sphincter (LOS) relaxation and augmentation of the crural diaphragm (CD) contraction. The purpose of this study was to determine the effects of stimulating mechano-receptors at the laryngopharynx on the LOS and CD by using an air pulse stimulation device. Air pulses were delivered via the internal channel of a flexible endoscope. Oesophageal, LOS, and CD pressures; CD electromyogram; and oesophageal pH 5 cm above the LOS were recorded in nine healthy subjects. Stimulation of the laryngopharynx induced LOS relaxation in the absence of swallow and oesophageal peristalsis. The stimulation of epiglottis and arytenoid produced higher incidence of LOS relaxation compared to the base of tongue. The magnitude of LOS relaxation differed significantly between the three anatomical sites, with greater relaxation occurring at the epiglottis and arytenoid compared with the base of the tongue. None of the LOS relaxations induced by laryngeal stimulation resulted in inhibition of the CD or gastroesophageal reflux. We conclude that stimulation of the laryngopharyngeal mechanoreceptors induces LOS but not CD relaxation. The LOS relaxation induced by laryngopharyngeal stimulation is not accompanied by acid reflux in fasting state.

Schwannoma of the cervical sympathetic chain. The Virginia experience

We present 4 cases of schwannomas arising from the cervical sympathetic chain. These lesions are uncommon and most often present as an asymptomatic solitary neck mass. Preoperative diagnosis can be difficult, even with the aid of computed tomography, magnetic resonance imaging, ultrasound, and angiography. While a paraganglioma can often be ruled out, exact determination of the nerve of origin is frequently elusive until the time of surgery. Operative excision remains the treatment of choice, often requiring sacrifice of a portion of the sympathetic chain. Postoperative Horner's syndrome is common, but does not appear to have an adverse effect on the patient.

Esthesioneuroblastoma: reflections of a 21-year experience

OBJECTIVES

To evaluate the results of standardized treatment of esthesioneuroblastoma at a single institution during a 21-year period and calculate pertinent parameters, i.e., metastatic disease (local, regional, distant), disease-free survival, and complications of treatment.

STUDY DESIGN

A retrospective review was conducted of all patients treated at a single institution from September 1976 through May 1998.

METHODS

Only those patients who received their complete evaluation and treatment at our institution were included in this analysis. Thirty-five patients met this criterion. In addition, results of epidemiological, pathological, and molecular analyses were evaluated to seek accurate indicators for clinical outcomes.

RESULTS

Six percent of patients presented with cervical metastatic disease, but ultimately 25.7% developed at least one episode of cervical metastases; 14.3% of patients developed a local recurrence an average of 6 years after diagnosis; and 37% of the patients ultimately developed at least one episode of metastatic disease. The disease-free survival for this cohort of 35 patients was 80.4% at 8 years. CNS complications occurred in 25.7% of the patients, 22.9% had orbital complications, 20% had systemic posttreatment problems, 18.2% had chemotoxic sequelae, 8.6% had infectious complications, and 14.3% had cosmetic sequelae. No epidemiological, pathological, or molecular factors appeared to be more accurate clinical indicators than the Kadish staging system.

CONCLUSIONS

This series of esthesioneuroblastoma patients (N=35) reflects an 8-year disease-free survival of 80.4%, representing a significant number of patients treated and followed at one institution for an extended period of time. No valuable pathological or molecular indicators to predict aggressive clinical behavior were found. The average time interval before recurrent disease developed was more than 6 years, far greater than that expected for other sinonasal malignancies. Therefore, extended follow-up is necessary for this patient group.

Activity-controlled circadian base rate

The current pacing rates are clustered around a fixed base rate since pacemaker patients are usually sedentary, resting, or sleeping most of the time. This fixed base rate is either too low for daytime hemodynamic support or too high for nighttime rest and recovery. Multiple Holter studies involving normal individuals have suggested that the resting base rate fluctuates during the course of the day. The circadian base rate (CBR) algorithm was designed to provide patients with a circadian change in paced resting rate and a normal rate distribution. The CBR algorithm, using a sophisticated accelerometer sensor, was developed and tested using the downloaded activity data from patients implanted with Trilogy DR+ pacemakers. Twenty-five patients (19 men, 6 women, age 72 +/- 9 years) were studied. Trilogy DR+ is able to record the detailed sensor and system behavior data for a week. During outpatient visits, the pacemaker was interrogated and the data accumulated in the pacemaker memory were downloaded. The CBR algorithm was applied to the activity variance histogram to calculate the base rate and to construct its histogram. The base rates in the CBR histogram are generally below 100 ppm with a distribution that mimics the natural sinus rate distribution of normal subjects. The CBR algorithm provides the highest daytime rates for hemodynamic support and the lowest nighttime rates for cardiac recovery, with a smoothly changing base rate modeling the normal circadian variation in heart rate.

Pacemaker-mediated polymorphic ventricular tachycardia

A patient with refractory bradycardia dependent polymorphic ventricular tachycardia (PMVT) underwent permanent pacemaker placement for suppression of her arrhythmia. Following implant, the patient had recurrent PMVT. Interrogation of the device revealed a factory programmed feature (+ PVARP on PVC) designed to prevent pacemaker-mediated tachycardia that led to cycle length variability and subsequent arrhythmia recurrence. This feature was deactivated and the patients' arrhythmia did not recur.

The role of preoperative adjuvant treatment in the management of esthesioneuroblastoma: the University of Virginia experience

OBJECTIVE

Multidisciplinary management of esthesioneuroblastoma has effected markedly increased survival during the past 20 years. The potential for radical craniofacial surgery for complete en bloc resection, the availability of advanced neuroimaging modalities, and the incorporation of neoadjuvant therapy into treatment strategies for tumor remission have all contributed to this accomplishment. However, a standard protocol for the management of these lesions has not been accepted; preoperative radiation and chemotherapy have been advocated, but neither radiographic nor clinical response has been quantified.

METHODS

Thirty-four consecutive patients with biopsy-proven esthesioneuroblastoma treated at one institution from 1976 to 1994 were reviewed to determine the effects of preoperative radiation therapy, with or without chemotherapy, on tumor size and long-term survival.

RESULTS

In a multivariate regression analysis, advanced age was predictive of decreased disease-free survival (P=0.008), whereas advanced Kadish stage was associated with a borderline higher rate of disease-related mortality (P=0.056). Two-thirds of the patients showed a significant reduction in tumor burden with adjuvant therapy. Patients with response to neoadjuvant therapy demonstrated a significantly lower rate of disease-related mortality (P=0.050). In this series, the overall 5- and 10-year survival rates were 81.0 and 54.5%, respectively.

CONCLUSION

Preoperative neoadjuvant therapy provides a valuable complement to radical craniofacial resection, leading to reduction in tumor burden. Patients experiencing reduction in tumor volume by neoadjuvant therapy demonstrate an improved prognosis.

Sebaceous carcinoma. Tumor progression through mutational inactivation of p53

BACKGROUND

Sebaceous carcinoma may masquerade for years as an inflammatory condition. In many cases, this may be because of the presence of longstanding intraepithelial disease (e.g., dysplasia or carcinoma in situ), which eventually progresses to invasive carcinoma recognized through tumefaction and a worsening clinical presentation. The mechanism for this tumor progression is unknown. In the Far East, human papilloma virus (HPV) has been suggested to play a role in the development of sebaceous carcinoma by inactivating tumor suppressor gene p53. Here, the authors explore the molecular basis of the progression of ocular sebaceous carcinoma.

METHODS

Cases of sebaceous carcinoma seen at the University of Virginia, Department of Ophthalmology, during the period from 1989 to 1996 were analyzed for HPV infection by in situ hybridization and polymerase chain reaction. The expression of p53, p21WAF-1, Bcl-2, and epithelial membrane antigen was examined by immunohistochemistry. In one of the cases, frozen tumor was available, allowing exons 5 through 9 of the p53 gene to be sequenced.

RESULTS

Seven cases were identified, all of which were from women. All were negative for HPV. In cases in which disease was restricted to dysplasia (carcinoma in situ), p53 but not p21WAF-1 was negative. In contrast, cases that contained a component of invasive or metastatic carcinoma showed striking hyperexpression of nuclear p53 in all of the malignant cells. In one of these cases, a G:C-->T:A transversion was found in the p53 gene. This mutation, characteristic of bulky carcinogens, substituted phenylalanine for cysteine 277, a residue that participates in hydrogen bonding to the p53 DNA binding consensus sequence.

CONCLUSIONS

Mutational inactivation of p53 may be involved in the progression of sebaceous carcinoma.

A two-step intervention of increase mammography among women aged 65 and older

OBJECTIVES

This study evaluated a two-step intervention for mammography screening among older women.

METHODS

Four hundred and sixty women, identified from physician practices, were randomized to a control or a two-step intervention (physician letter and peer counseling call) group. Women in the intervention group who obtained a mammogram received a grocery coupon.

RESULTS

Over the 12 months of the study, more women in the intervention group than in the control group obtained mammograms (38% vs 16%). The most dramatic difference was in the higher odds that women in the intervention group would obtain a mammogram within 2 months (odds ratio = 10.5).

CONCLUSIONS

The intervention significantly increased screening mammography. Future efforts must be multifaceted and incorporate the unique concerns of older women.

Sinonasal undifferentiated carcinoma: CT and MR imaging of an uncommon neoplasm of the nasal cavity

PURPOSE

To determine the computed tomographic (CT) and magnetic resonance (MR) imaging appearance of sinonasal undifferentiated carcinoma.

MATERIALS AND METHODS

Findings from 11 patients with histopathologically proved sinonasal undifferentiated carcinoma were retrospectively reviewed. All 11 patients had undergone CT, and six of them had undergone MR imaging.

RESULTS

The tumors usually were large (larger than 4 cm in maximum dimension in eight patients), had poorly defined margins, and arose within the ethmoid sinuses and superior nasal cavity. The aggressive nature of the tumor was demonstrated by bone destruction (n = 10) and by invasion of adjacent structures, including paranasal sinuses (n = 10), anterior fossa (n = 7), orbits (n = 4), pterygopalatine fossa (n = 2), parapharyngeal space (n = 1), and cavernous sinus (n = 1). On contrast material-enhanced CT scans, all tumors were enhanced to varying degrees. They tended to be noncalcified (n = 10) and often caused sinus obstruction (n = 10). MR signal intensity of the lesions was isointense to muscle on T1-weighted images in all six patients and iso- to hyperintense on T2-weighted images in five patients. Heterogeneous enhancement of tumors was seen on gadolinium-enhanced images.

CONCLUSION

Sinonasal undifferentiated carcinoma cannot be distinguished from other tumors of this region (with the possible exception of melanoma) on the basis of imaging features.

Management of advanced-stage laryngeal cancer

Although the total laryngectomy is still the most reliable and simplest method for treating advanced laryngeal carcinoma, the shortcomings of the sequelae of the procedure have provided a constant challenge for improvement and change. Two alternatives that have shown some success are the Pearson near-total laryngectomy and the supracricoid partial laryngectomy with cricohyoidopexy and with cricohyoidoepiglottopexy. This article covers the procedural differences between these alternatives to the total laryngectomy.

Oral squamous cell carcinoma in association with dental osseointegrated implants. An unusual occurrence

The major risk factors for developing oral cavity squamous cell carcinoma in the United States include smoking, alcohol, syphilis, and herpes simplex virus type 1. It is difficult to locate a report of squamous cell carcinoma arising in association with osseointegrated dental implants, despite their frequent use. We report an unusual series of 3 cases of squamous cell carcinoma arising around an implant.

Effect of pentaphasic pulse sequence as an impedance sensor on standard electrocardiographic recordings

Two advances in cardiac pacing have resulted in an internal conflict in some pacemakers. One is the development of a standard lead physiological sensor and the other is protection from electromagnetic interference (EMI). One popular type of standard lead sensor uses sub-threshold pulses to measure intracardiac and intrathoracic impedance changes, i.e., minute ventilation. Recent clinical observations and extensive in vitro testing have verified that digital cellular phones can be troublesome. Large feedthrough capacitors (FCs), effective in blocking the EMI, will preclude sensing of the standard impedance-based signals. A variety of pulse configurations were studied that might be effective for a sensor-based impedance signal while allowing the pacemaker to continue to use large Fcs protecting them from environmental EMI. In comparison to both monophasic and biphasic pulse sequences, a pentaphasic pulse sequence was effective as an impedance sensor, still allows large FCs to function as an effective filter for environmental EMI, and would not produce artifacts on surface ECG.

Role of ischemic gradient in neovascularization of interpolated skin flaps

OBJECTIVES

To investigate the significance of the ischemic gradient between interpolated skin flaps and the recipient bed and to determine its role in flap viability.

DESIGN

Bilateral interpolated skin flaps were elevated in 10 pigs and intravenous fluorescein was used to define a border of pedicle perfusion. Flaps were assigned to 1 of 2 groups: proximal flaps, which were contained within the fluorescein border, or distal flaps, which extended 3 cm beyond the fluorescein border. Flaps were then transferred to an adjacent cutaneous defect and pedicles were divided after 2 weeks. The flap and pedicle portions were evaluated separately and viability was quantified.

SUBJECTS

Ten adolescent pigs with bilateral flaps. None were withdrawn.

INTERVENTION

Intravenous fluorescein (20 mg/kg) to determine extent of perfusion in the flaps.

RESULTS

Proximal flaps (n = 10) maintained excellent viability with the pedicles attached. After pedicle division, however, partial flap and pedicle necrosis developed. Distal flaps (n = 10) promptly showed signs of ischemia and congestion but soon showed improved vascularity. A statistically significant improvement was seen in mean percent viability of the distal group compared with the proximal group (P < .05) (Student t test).

CONCLUSION

The more ischemic flap-pedicle complex resulted in greater viability after pedicle division. The ischemic gradient seemed to represent a potent angiogenic stimulus to the recipient bed.

Safe performance of magnetic resonance imaging on five patients with permanent cardiac pacemakers

Five patients with permanent cardiac pacemakers (Pacesetter models 261, 285, 2016, 2020, 2022) underwent magnetic resonance imaging (MRI). Only one patient (underlying rhythm asystole) was pacemaker dependent. A variety of pacing configurations (single and dual chamber; unipolar and bipolar; sensor and nonsensor driven) were scanned. A thorough evaluation of each pacing system was performed before and after scanning including determination of pacing and sensing thresholds. During MRI the patient was monitored using either ECG, pulse oximetry, or direct voice contact. In four patients heavy dressings were applied over the pacemaker pocket site. Patients were asked to report any symptoms experienced during MRI.

RESULTS

The four nonpacemaker dependent patients remained in sinus rhythm throughout the MRI. During and after the MRI all pacemakers continued to function normally except for one transient pause of approximately 2 seconds (noted by pulse oximeter) toward the end of the scan. This occurred in a pacemaker dependent patient with a unipolar dual chamber device programmed DOO. No patient experienced any torque or heat sensation.

CONCLUSION

When appropriate strategies are used our experience suggests that MRI may be performed, when necessary, with an acceptable risk-benefit ratio to the patient. It is unclear whether the isolated pause that was observed was due to the effect of the MRI, an artifact with the monitoring system, or oversensing by the pacemaker. Appropriate patient selection, close monitoring during the scan, and follow-up after MRI are of paramount importance. Further study is necessary to refine the appropriate strategies that could be used to consistently perform MRI safely in a selected pacemaker population.

Preservation of the eye in the treatment of sinonasal malignant neoplasms with orbital involvement. A confirmation of the original treatise

OBJECTIVE

To continue the retrospective analysis reported in 1988 that supported preservation of the eye in the treatment of sinonasal cancers when bony erosion of the orbit was noted on pretreatment radiographic analysis.

DESIGN

Using the eye-sparing protocol previously reported, which included preoperative radiotherapy (with or without chemotherapy, depending on tumor size, involvement, or other characteristic) for malignant neoplasms of the superior nasal vault that had eroded the bony orbit, retrospective analysis of the results of therapy for the additional 33 patients treated between 1986 and 1993 was performed. These data were added to those from the original series to provide a total of 74 patients. Forty-one patients (55%) showed bony erosion at initial evaluation and 14 (19%) had periorbital involvement. During surgery, the periorbita was evaluated by frozen section control. If tumor was found, that region of periorbita was resected and, if necessary, replaced with fascia or split-thickness graft.

RESULTS

Five patients from the original series had orbital sacrifice. Of the remaining 36 patients, 4 (11%) had recurrent disease involving the orbit, but not at the primary site. Twenty (55%) of the 36 patients had no orbital complications, and only 1 (3%) had a permanent motility disturbance and 4 (13%) developed cataracts after radiotherapy.

CONCLUSION

With the use of preoperative radiotherapy in resection of involved periorbita with frozen section control in tumors of the sinonasal vault that involve the bony orbit, the eye can be spared in most instances without compromising oncologic safety.

Management of the eye in the treatment of sinonasal cancers

Malignant neoplasms of the nose and paranasal sinuses typically manifest at a late stage and commonly abut or invade the orbit. Careful ophthalmologic examination and fine-cut CT provide the most accurate preoperative assessment of orbital involvement, providing guidance for treatment with a combination of radiation therapy and surgical resection. Although some surgeons still aggressively remove the eye when tumor abuts or involves limited periorbita, we have shown that this approach is unnecessarily ablative. The cosmetic, functional, and psychologic consequences of the loss of an eye mandate that every effort should be made to preserve the eye as long as oncologic safety is not compromised. The evidence is mounting that this is safe and organ sparing, and leaves functioning eyes. With the use of preoperative radiation therapy and frozen-section control of the periorbita, the eye can often be spared without increasing local recurrences or survival, and adequate postoperative function can be maintained.

Cyclin D1 (PRAD1, CCND1) and glutathione-S-transferase pi gene expression in head and neck squamous cell carcinoma

Chromosome 11q13 amplification has been identified in a subset of head and neck squamous cell carcinomas (H&N SCCs). This region contains several putative oncogenes, including cyclin D1 (PRAD1, CCND1), which encodes for an important cell cycle regulatory protein, and the locus encoding for the drug-detoxifying enzyme glutathione-S-transferase-pi (GST-pi). To determine the relationship of cyclin D1 and GST-pi gene amplification to expression of the encoded proteins, the authors examined 64 H&N SCCs by both Southern blot hybridization and immunohistochemistry, using a recently described, affinity-purified, anticyclin D1 polyclonal antibody no. 19 as well as a polyclonal antibody against GST-pi. Anticyclin D1 antibody no. 19 labeled the tumor cell nuclei in 28 (44%) of the H&N SCCs, whereas cytoplasmic immunoreactivity for GST-pi was noted in 55 (86%) neoplasms. By Southern blot 24 tumors (37.5%) showed twofold to tenfold amplification of 11q13 loci; only two of these were coamplified for GST-pi. Immunopositivity with anticyclin D1 antibody no. 19 but not anti-GST-pi significantly correlated with 11q13 amplification (P < .0001). Of the 28 tumors positive with anticyclin D1 antibody no. 19, however, only 18 (64%) were amplified for 11q13, and six amplified tumors did not react with the no. 19 antibody. A strong trend was noted between anticyclin D1 antibody no. 19 reactivity and a hypopharyngeal primary site (P = .053), but no correlations were observed between immunoreactivity and cytological grade, architectural pattern, pathological stage, and disease-free or overall survival. The inconsistent association of cyclin D1 immunoreactivity with 11q13 amplification indicates that other mechanisms may exist for protein overexpression. Immunoreactivity for the GST-pi protein is prevalent in H&N SCC but is clearly unassociated with amplification. In this series, the presence or extent of cyclin D1 and GST-pi immunoreactivity was of no proven prognostic benefit in H&N SCC.

Chromosome 11q13 amplification in head and neck squamous cell carcinoma. Association with poor prognosis

OBJECTIVE

To determine the clinical and prognostic significance of chromosome 11q13 amplification in squamous cell carcinoma of the head and neck.

DESIGN

Retrospective clinical analysis.

SETTING

University and private cancer centers.

PATIENTS

Fifty-six patients with pathologically confirmed head and neck squamous cell carcinoma whose tumors had been assayed for the presence or absence of chromosome 11q13 amplification.

MEASUREMENTS

The degree of DNA amplification in each tumor was determined using chromosome 11q13 probes for the bcl-1 major translocation cluster, PRAD1/cyclin D1 (CCND1), the fibroblast growth factor gene HST1, EMS1, and glutathione-S-transferase-pi-1. The presence or absence of amplification in each patient was correlated with primary site, tumor stage, nodal status, presence or absence of distant metastasis, disease recurrence, time to recurrence, clinical outcome (disease status), and overall survival.

RESULTS

Amplification of chromosome 11q13 was identified in 39% (22/56) of patients. Recurrent or persistent disease was identified in 82% (18/22) of cases with amplification and 50% (14/28) of nonamplified cases (P = .04). Mean time to recurrence was shorter in cases with amplification (6.2 months) than those without amplification (10.1 months) (P = .01). Eighteen patients (82%) with amplification and 10 patients (38%) without amplification died of disease or are alive with disease (P = .001). The mean follow-up period was 15.8 months for patients with amplification and 18.6 months for patients without amplification. Overall survival was significantly diminished in patients with amplification (P = .002). Amplification was not related to nodal status, distant metastases, or initial disease stage.

CONCLUSIONS

Amplification of chromosome 11q13 loci may be an important biologic marker indicating poor prognosis, independent of clinical stage in head and neck squamous cell carcinoma, and it should be assessed in prospective trials to determine its utility for stratifying treatment and determining prognosis.

Definitive radiotherapy for T1 and T2 squamous cell carcinoma of the tonsil

BACKGROUND

To assess whether survival or local control of early squamous cell carcinoma of the tonsil has been compromised by a moderate-dose approach.

METHODS

Between 1970 and 1989, 185 patients with SCCa of the tonsil were seen at our institution. Fifty-three patients with T1 (30) and T2 (23) lesions treated with definitive radiotherapy were reviewed. Median follow-up was 60 months. The effects of total dose and site of the primary on survival and local regional control were analyzed.

RESULTS

Three-year determinate survival was 77%. Mean total dose was 63.1 Gy. Site of the primary significantly affected survival (86% for fossa, 54% for pillars, p < 0.025). Local control at 2 years was 81% and was independent of dose > or = 63 Gy or site of the primary. Grade 4 complications defined by the RTOG/EORTC Acute Morbidity criteria occurred in three patients.

CONCLUSIONS

Tumor doses on the order of 63 Gy or less result in excellent local control and survival rates for T1 and T2 carcinomas of the tonsil. Local control rates are better for fossa lesions than for pillar lesions.

Effect of implantable nonthoracotomy defibrillation system on permanent pacemakers: an in vitro analysis with clinical implications

Implantable cardioverter defibrillation systems are capable of delivering over 700 volts, and upwards of 40 joules (J) directly to the heart. Nonthoracotomy lead (NTL) systems allow the delivery of this energy to the inside of the heart, and potentially in close proximity to the leads of an endocardial pacing system. The effect of repeated maximal energy discharges (stored energy 40 J, delivered energy 38 J), utilizing both monophasic as well as biphasic shock pulses delivered via two different configuration NTL systems on a series of Pacesetter polarity programmable present generation single, and dual chamber pacemakers was evaluated in vitro using a saline test tank. All pulse generators studied demonstrated normal function and were not reprogrammed nor adversely affected by repeated defibrillation shocks. The current induced in the leads was assessed, and shown to be as high as 1.5 amps in the proximal conductor and 1.2 amps in the distal conductor of the ventricular lead, which may cause damage at the electrode-myocardial interface, and explain some of the postshock rise in capture and sensing thresholds that have been reported with implanted pacing systems postdefibrillation.

A new automode switch algorithm for supraventricular tachycardias

Patients with complete heart block on a spontaneous, or iatrogenic basis who also have recurrent supraventricular tachycardias, particularly atrial fibrillation and flutter, are often difficult to manage. Various techniques include: independently programmable maximum tracking and maximum sensor rates, limiting the maximum atrial tracking rate to the sensor response of the pacemaker, or automatically switching from DDDR to VVIR based upon the sensed atrial rate. This article will describe a mode switch algorithm that allows for an independently programmable atrial tachycardia detection rate (ATDR). This allows mode switching to occur only in response to the patient's pathological tachyarrhythmia, and not during normal upper rate response. The ATDR is based upon a filtered atrial rate, which will prevent an isolated premature beat from initiating the algorithm. In addition, the unit can be programmed to switch to either DDI, DDIR, VVI, or VVIR. Extensive event counters in the pulse generator allows the system to record and store the number of algorithm activations, the average atrial rate which triggered each mode switch, and the duration of the mode switch. These reports are accessible at each follow-up visit.

Craniofacial resection at the University of Virginia (1976-1992): survival analysis

BACKGROUND

The purpose of this study is to evaluate the survival of patients treated at the University of Virginia Health Sciences Center with an anterior craniofacial resection in conjunction with radiotherapy and/or chemotherapy for malignancies of the superior sinonasal cavity. In addition, the impact of aggressive salvage therapy for patients with recurrent disease is considered.

METHODS

Between June 1976 and December 1992, a total of 45 patients underwent a craniofacial resection by the Departments of Otolaryngology-Head and Neck Surgery and Neurological Surgery at the University of Virginia. One patient was excluded from the analysis because his neoplasm was benign. Another patient died 2 days postoperatively from multiple strokes. The remaining 43 patients were divided into two subgroups: (1) patients with esthesioneuroblastoma (24 patients) and patients with non-esthesioneuroblastoma malignancies (19). Their survival curves were estimated for the percent survival free of disease by month of follow-up using the product limit of Kaplan and Meier. In addition, the salvage treatment for recurrences was examined for both groups.

RESULTS

The 5-year disease-free survival rate for the entire group was 77%, with a 2.3% postoperative mortality. The 5-year disease-free survival for the esthesioneuroblastoma patients was 90%, and that for the non-esthesioneuroblastoma group was 59.1% (p = 0.028). Four of 8 esthesioneuroblastoma patients who recurred and were treated with aggressive salvage therapy were without evidence of disease 5 years after completion of therapy, and 3 of the 10 non-esthesioneuroblastoma patients salvaged were without evidence of disease 57.3 months after therapy (39% surgical salvage).

CONCLUSIONS

There is a statistically significant difference between the 5-year disease-free survival for the esthesioneuroblastoma patients and the non-esthesioneuroblastoma patients (90% vs 59.1%; p = 0.028), and aggressive salvage therapy appears to be a more successful option in the esthesioneuroblastoma group of patients.

Adjusting heart rate during sleep using activity variance

In order to mimic the natural decrease in heart rate that occurs during sleep, an algorithm was devised to decrease the base rate to a programmable sleep rate. The algorithm was developed using activity and sinus rate data obtained from 18 normal subjects ranging in age from 22-80 years. The data were recorded in the event record of a "taped-on" pacemaker. The surface ECG signal was used to inhibit a pacer programmed to VVI at 45 ppm. The ECG documented the sinus rate while the accelerometer-based activity signals were recorded in an event record. An algorithm was used to estimate the smoothed acceleration variance every 26 seconds. The activity variance was stored in a histogram.

RESULTS

The lower 7/24ths of the histogram entries were primarily attributable to sleep. If the activity variance was entered into the lower 7/24ths of the histogram and the accelerometer reading was below rate responsive threshold, the base rate was switched to sleep rate. Using least mean squares to estimate optimal slope, base rate, and sleep rate, the root mean square error between activity derived heart rate and sinus rate was 12 beats/min.

CONCLUSION

This study supports using an estimate of activity variance to automatically decrease pacing rate below programmed base rate. This decrease may be actuated during an afternoon nap or nighttime sleep.

Pearson near-total laryngectomy: a reproducible speaking shunt

BACKGROUND

Since 1980, Pearson and his associates at the Mayo Clinic have accrued an increasing number of patients whom they have treated with what is now designated as a "near-total" laryngectomy rather than a total laryngectomy. Despite the positive reports of the value of this procedure in providing speech by an internal shunt, the use of this total laryngectomy alternative has not gained wide acceptance. We report our experience with treating 11 patients during a 3-year period using the near-total laryngectomy.

METHODS

Between September 1989 and September 1992, 11 patients with the following anatomic lesions were offered and accepted the option of the near-total laryngectomy: (1) T3 or early T4 glottic squamous cell carcinoma that did not involve the interarytenoid space or the vocal process of the opposite arytenoid; (2) T3 supraglottic squamous cell carcinoma with a fixed vocal cord in which a supraglottic laryngectomy could not be performed; (3) T2, T3 pyriform sinus squamous cell carcinomas; (4) radiotherapy failure early glottic lesions in which a vertical hemilaryngectomy for salvage was not able to be performed and met the requirements in (1); and (5) large hypopharyngeal lesions in which the larynx would be sacrificed to prevent aspiration but was not involved with tumor.

RESULTS

Nine of 11 patients (82%) attained successful speech in an average of 5.3 months. Two of the 11 patients required a completion laryngectomy, both due to wound complications. All but two of the patients received postoperative radiotherapy. Of the nine successful speakers, five have had an occasional droplet of fluid through the shunt; three have been on a permanent basis and two transient. Eighty-nine percent of the speaking patients (8 of 9) are alive without disease, a mean of 25.5 months after therapy completion.

CONCLUSION

The near-total laryngectomy can be performed outside the Mayo Clinic with creditable results, with 82% of the patients attaining successful speech, an average of 5.3 months postoperatively. Eighty-nine percent of the speakers have had a mean disease-free survival of 25.5 months. Analysis of larger series from multiple institutions in conjunction with voice analyses of these patients compared to those with tracheoesophageal punctures is needed to confirm our initial enthusiasm for this procedure.

MR of esthesioneuroblastoma (olfactory neuroblastoma) and appearance after craniofacial resection

PURPOSE

To analyze the MR characteristics of a series of patients with esthesioneuroblastoma and discuss the typical surgery and its postoperative MR appearance.

METHODS

The MR studies of 15 patients with the pathologic diagnosis of esthesioneuroblastoma (also known as olfactory neuroblastoma) were retrospectively reviewed and correlated with CT and surgical findings. The postoperative MR studies of 10 patients who underwent craniofacial resection were also reviewed.

RESULTS

In all cases the tumors arose in the superior nasal cavity and extended into the ethmoid cells. In some instances the tumors extended into the other paranasal sinuses, orbits, anterior cranial fossa, and cavernous sinus. The tumors were typically expansile and destructive in their growth patterns. Compared with brain gray matter, the tumors were hypointense on T1-weighted images and isointense to hyperintense on T2-weighted images. Nine tumors were heterogeneous and 6 were homogeneous. Contrast enhancement ranged from mild to marked. MR was useful for characterizing the various tissues and distinguishing fluid in the postoperative nasal cavity.

CONCLUSIONS

Esthesioneuroblastoma, although an uncommon tumor, may be suspected in lesions of the superior nasal cavity demonstrating both expansile and destructive growth properties. The MR findings are otherwise nonspecific. MR is the imaging modality of choice for depicting local tumor extension and evaluating for recurrence after craniofacial resection.

Esthesioneuroblastoma. Long-term outcome and patterns of failure--the University of Virginia experience

BACKGROUND

Esthesioneuroblastoma is a rare tumor arising from olfactory epithelium. This retrospective review analyzed the patterns of failure and long term outcome of patients with esthesioneuroblastoma evaluated at a single institution.

METHODS

Forty patients with esthesioneuroblastoma were evaluated at the University of Virginia, with a median follow-up of 130 months. In most cases, treatment consisted of combined-modality therapy, including radiotherapy and surgery for Stages A and B disease and the addition of chemotherapy for Stage C disease. Fifteen patients received chemotherapy that included cyclophosphamide plus vincristine. Thirty-eight patients received radiotherapy, with a median dose of 50 Gy. Initial surgery for 23 patients included craniofacial resection, whereas the remainder had less extensive surgery (3 had no initial surgery). Five patients were salvaged with high dose chemotherapy and autologous bone marrow transplantation (CTX/BMT).

RESULTS

Actuarial survivals at 5, 10, and 15 years are 78%, 71%, and 65% respectively. Fifty-five percent of patients failed therapy, and 68% of the failures were locoregional. Thirty-nine percent of recurrences occurred later than 5 years from diagnosis. Three of the five patients were successfully salvaged with CTX/BMT compared with four of seventeen patients who underwent conventional salvage therapy.

CONCLUSIONS

Esthesioneuroblastoma is associated with long term survival and late recurrences. Multimodality therapy should be used initially. Durable remissions of failures can be achieved with CTX/BMT:

Comparison of cardiac pacing modes in patients with chronic obstructive pulmonary disease

STUDY OBJECTIVE

This study compares the relative benefits of dual chamber adaptive rate pacing (DDDR) with ventricular adaptive rate pacing (VVIR) in patients with chronic obstructive pulmonary disease (COPD).

STUDY DESIGN

Cardiac hemodynamics were evaluated with serial exercise tests. A minimum of 2 h was allowed between studies. Pulmonary gas exchange was measured and cardiac output (CO) was determined at rest and immediately after maximum exercise by Doppler echocardiography.

PATIENTS

Sixteen patients with DDDR pacemakers were studied. Eight patients had COPD and eight patients had normal lung function (NLF). Baseline lung function was documented with spirometry.

INTERVENTIONS

The patients with NLF functioned as a control group. Prior to entry into the study, the rate-modulated parameters of the pacemaker were programmed to a clinically determined optimal set of parameters for each individual patient. These were not changed for the duration of the study.

RESULTS

Both groups showed a statistically significant improvement in exercise duration, CO at maximum exercise, and cardiac output difference (CODiff) with the dual chamber adaptive rate pacing mode (DDDR). (COdiff is the change in CO from rest to maximum exercise.) Patients with NLF also showed a significant improvement in anaerobic threshold (AT) and VCO2 max with DDDR. Patients with lung disease showed a statistically significant improvement at all levels of exercise in the ventilatory equivalent for oxygen.

CONCLUSION

In this study, those patients with chronic lung disease who required cardiac pacing performed significantly better in the DDDR mode as compared with the VVIR mode. Therefore, the DDDR pacing mode should provide an improved quality of life for the patient with COPD who also requires cardiac pacing.

Chromosome 11Q13 amplification in head and neck squamous cell carcinoma

OBJECTIVE

To establish the frequency and clinicopathologic correlates of 11q13 amplification in head and neck squamous cell carcinoma.

DESIGN

Retrospective clinicopathologic analysis.

SETTING

University and private cancer centers.

PATIENTS

Eighty-five patients with pathologically confirmed head and neck squamous cell carcinoma.

MEASUREMENTS

The degree of DNA amplification in each tumor was determined using chromosome 11q13 probes for the bcl-1 major translocation cluster, PRAD1/cyclin D1 (CCND1), the fibroblast growth factor gene HST1, EMS1, and glutathione S transferase, pi-1. The presence or absence of amplification was correlated with anatomic site, tumor stage, cytologic grade, histologic pattern, and mitotic activity.

RESULTS

Thirty-one patients (36%) showed a twofold to 10-fold amplification of 11q13 loci compared with the chromosome 11q23 ETS1 control probe. Twenty-nine of these encompassed bcl-1 through EMS1 loci; one sample showed only bcl-1 and PRAD1/cyclin D1 plus HST1 amplification, with another amplified at HST1 and EMS1 with minimal or no bcl-1 and PRAD1/cyclin D1 amplification. Amplification was significantly correlated with high cytologic grade, a diffusely infiltrative growth pattern, and with a hypopharyngeal primary site.

CONCLUSIONS

Chromosome 11q13 amplification in head and neck squamous cell carcinoma is correlated with an aggressive histologic appearance and hypopharyngeal primary site and should be assessed in prospective clinical trials to determine its utility for treatment stratification and prognosis. Although PRAD1/cyclin D1 and EMS1 have been implicated in the pathogenesis of neoplasms with 11q13 amplification, rare cases with more limited amplicon size suggest that another relevant gene or genes may exist between these loci.

Cervical manifestations of fibrosing mediastinitis: a diagnostic and therapeutic dilemma

Fibroinflammatory and fibrosclerosing lesions involving the head and neck outside the thyroid and orbit are exceedingly rare. We present two cases of fibroinflammatory and fibrosclerosing lesions originating in the mediastinum which extended superiorly to involve soft tissues of the neck. These cases indicate that a subset of fibroinflammatory and fibrosclerosing lesions found in the head and neck originate in the mediastinum.

Recurrent cervical intraepithelial neoplasia in human immunodeficiency virus-seropositive women

OBJECTIVE

To determine the effect of human immunodeficiency virus (HIV) infection on the rate of recurrence of cervical intraepithelial neoplasia (CIN) after standard ablative therapy, and to correlate the degree of immunosuppression with treatment results.

METHODS

The clinical courses of 44 HIV-positive women with CIN were compared with those of 125 HIV-negative women. Patients were treated with cryotherapy, laser therapy, or cone biopsy per standard indications and were followed with cytology at regular intervals, with a range of follow-up of 3-43 months.

RESULTS

Seventeen of 44 HIV-positive women (39%) developed biopsy-proven recurrent CIN, compared to 11 of 125 HIV-negative women (9%) (P < .01). The distributions of CIN severity, lesion size, and modality of treatment were similar in the two groups. In HIV-negative patients, recurrent CIN was associated with increasing grade, but in HIV-positive patients, recurrence was related to increasing immunosuppression. The mean CD4 count in HIV-positive patients with recurrence was 239/mm3, compared to 367/mm3 in HIV-positive patients who remained free of CIN. Only 18% of HIV-positive patients with CD4 counts over 500/mm3 had recurrence, compared to 45% of those with CD4 counts under 500. There was a trend toward poorer treatment results with the use of cryotherapy in HIV-positive patients. All recurrences occurred in patients whose mode of acquisition of HIV was heterosexual transmission.

CONCLUSION

Recurrence rates of CIN after standard treatment in HIV-positive women are high, and recurrence is related to immune status in this high-risk group. Therapeutic strategies that address these treatment failures should be developed for HIV-seropositive women.

Sinonasal undifferentiated carcinoma: a ray of hope

In 1987, we published a case series of a newly-described, highly malignant neoplasm, termed sinonasal undifferentiated carcinoma, in which treatment results were poor. In this updated study, we report the followup for the original three surviving patients and for six additional cases whose tumors were diagnosed between January 1987 and October 1991. These data suggest that the prognosis for patients with localized disease may be better than originally described.

Radiotherapy for basaloid squamous cell carcinoma of the head and neck

Basaloid squamous cell carcinoma (BSCC) of the head and neck is a recently described high-grade variant of squamous cell carcinoma. It is a biologically virulent neoplasm with a propensity for nodal, as well as systemic, metastases. Because of the limited number of published reports, we reviewed data from patients of the University of Virginia Health Sciences Center and identified 16 cases of BSCC. The intent of this study was to determine the role of radiotherapy in the treatment of BSCC and better define the clinical features of this entity. Radiotherapy alone, or in combination with surgery, resulted in excellent local control rates. Distant metastases, chiefly pulmonary, occurred in more than half of the patients.

The serratus anterior free tissue transfer for craniofacial reconstruction

The serratus anterior muscle was used as a free tissue transfer to reconstruct complex craniofacial defects in 5 patients. Serratus anterior muscle alone and serratus anterior muscle with rib were the transfers made. All flaps survived and scapular winging did not occur. The serratus anterior muscle has several advantages for the reconstruction of medium-sized craniofacial defects. Because of its position, a two-team approach is possible. It has a consistent pedicle anatomy and low donor site morbidity. It has a large caliber vessel and a long pedicle. When compared with the commonly employed rectus abdominis flap for moderate-sized defects, the serratus muscle offers greater versatility in design and has the option of incorporating bone and innervated muscle without increasing significant donor site morbidity.