Analysis of fentanyl in urine by DLLME-GC-MS

Fentanyl is a synthetic narcotic anesthetic ∼80-100 times more potent than morphine. Owing to the potential for its abuse, the drug may be included in a forensic toxicology work-up, which requires fast, precise and accurate measurements. Here, the stability of fentanyl was assessed when stored at three different temperatures (-20, 4 and 25°C) in synthetic urine. Stability at those three temperatures was demonstrated over 12 weeks upon analysis by gas chromatography-mass spectrometry with a deuterated internal standard (fentanyl-D5) utilizing three different extraction techniques: liquid-liquid extraction (LLE), solid-phase extraction and dispersed liquid-liquid microextraction (DLLME). The DLLME method was then optimized before use in the analysis of fentanyl in urine samples obtained from autopsy cases at the El Paso County Coroner's Office. Accuracy of the DLLME method was assessed by completing spike and recovery studies at three different fortification levels (10, 100 and 250 ng/mL) with excellent recovery (89.9-102.6%). The excellent comparability between DLLME and LLE is demonstrated (Bland-Altman difference plot with a mean difference of 4.9 ng/mL) and the use of this methodology in the analysis of forensically relevant samples is discussed.

The 5-year direct medical cost of neonatal and childhood stroke in a population-based cohort

BACKGROUND

Despite increasing awareness of the long-term impact of pediatric stroke, there are few estimates of the costs of care. We examined acute and 5-year direct costs of neonatal and childhood stroke in a population-based cohort in Northern California.

METHODS

We obtained electronic cost data for 266 children with neurologist-confirmed strokes, and 786 age-matched stroke-free controls, within the population of all children (<20 years) enrolled in a large managed care plan from 1996 through 2003. Cost data included all inpatient and outpatient health service costs including care at out-of-plan facilities. Costs were assessed for 5 years after stroke, expressed in 2003 US dollars, and stratified by age at stroke onset (neonatal, defined as <29 days of life, vs childhood). Stroke costs were adjusted for costs in stroke-free age-matched controls.

RESULTS

Average adjusted 5-year costs for pediatric stroke are substantial: $51,719 for neonatal stroke and $135,161 for childhood stroke. The average cost of a childhood stroke admission was $81,869. The average birth admission cost for a neonatal stroke was $39,613; adjustment for control birth admission costs reduced this by only $4,792, suggesting the stroke accounted for 88% of costs. Even among neonates whose strokes were not recognized until later in childhood ("presumed perinatal strokes"), admission costs exceeded those of controls. Chronic costs were highest in the first year poststroke, but continued to exceed control costs even in the fifth year by an average of $2,016.

CONCLUSIONS

The economic burden of neonatal and childhood stroke is both large and sustained.

Influence of harvest processes on pork loin and ham quality1

The purpose of this study was to determine the specific effects of extending the interval between dwell time and the duration of scalding on pork quality attributes. Sixty-four Duroc x Yorkshire pigs were randomly assigned to a 2 x 2 factorial treatment arrangement. Treatments included extending the dwell duration from 5 to 10 min and extending the scald duration from 5 to 8 min. All carcasses entered the cooler 50 min after exsanguination. At exsanguination, blood was collected for three 1-min intervals and then for a final 2-min period. Temperature and pH of the LM and semimembranosus muscle (SM) were measured at 45 min, and at 2, 4, 6, and 24 h postmortem (PM). Hunter L*, a*, and b* values were determined on the LM, SM, and biceps femoris (BF). Purge loss was measured on the SM, BF, and the sirloin end of the loin. Drip loss was measured in duplicate from LM chops after 1 and 5 d of storage. Warner-Bratzler shear force (WBS) measurements were determined on LM chops aged 1, 3, 5, and 7 d PM. Over 99% of the collected blood was obtained during the first 3 min after sticking. Carcasses scalded for 8 min had greater (P < 0.05) semi-membranosus 2 h temperature (28.8 degrees C) than carcasses scalded 5 min (27.3 degrees C). An 8-min scald process resulted in longissimus dorsi chops with lower hue angle and greater WBS values than the 5-min scald process. Increasing dwell time from 5 to 10 min resulted in biceps femoris chops with greater hue angle and loin chops with greater WBS values at 3 d PM. Harvest processes did not significantly affect subjective quality scores, Hunter L* values, purge or drip loss. Lengthening the duration of dwell and scalding may result in a more rapid PM pH decline. Reducing the duration of scalding may lead to increased time for manual removal of hair. Because of differences in facilities, it is recommended that individual facilities monitor dwell and scald durations to determine how to best minimize time of entry into the cooler.

Critically ill obstetric patients in an American and an Indian public hospital: comparison of case-mix, organ dysfunction, intensive care requirements, and outcomes

OBJECTIVE

To compare case-mix, health care practices, and outcome in obstetric ICU admissions in inner-city teaching hospitals in economically developed and developing countries.

DESIGN

Retrospective study.

SETTING

Ben Taub General Hospital (BTGH), Houston, Texas, and King Edward Memorial Hospital (KEMH), Mumbai, India.

PATIENTS

Women admitted during pregnancy or 6 weeks postpartum between 1992 and 2001.

MEASUREMENTS AND RESULTS

Patients from BTGH (n=174) and KEMH (n=754) had comparable age, number of organs affected, incidence of medical disorders (30%), liver dysfunction, and thrombocytopenia. Fewer KEMH patients received prenatal care (27 vs 86%) and came to hospital within 24 h of onset of symptoms (60 vs 90%). They had higher APACHE II scores (median 16 vs 10), greater incidence of neurological (63 vs 36%), renal (50 vs 37%), and cardiovascular dysfunction (39 vs 29%). Severe malaria, viral hepatitis, cerebral venous thrombosis, and poisoning were common medical disorders. The BTGH group had higher incidence of respiratory dysfunction (59 vs 46%) and disseminated intravascular coagulation (40 vs 23%), placental anomalies, HELLP syndrome, chorioamnionitis, peripartum cardiomyopathy, puerperal sepsis, urinary infection, bacteremia, substance abuse, and asthma. More BTGH patients required mechanical ventilation and blood component therapy, whereas more KEMH patients needed dialysis. Of BTGH patients, 78.2% were delivered by cesarean section (vs 15.4%). Maternal (2.3 vs 25%) and fetal (13 vs 51%) mortality were lower in BTGH patients.

CONCLUSIONS

There were marked differences in medical diseases, organ failure, and intensive care needs. Higher mortality in the Indian ICU may be due to difference in case mix, inadequate prenatal care, delay in reaching hospital, and greater severity of illness.

Does a selective adenosine A(1) receptor agonist protect against exercise induced ischaemia in patients with coronary artery disease?

BACKGROUND

The "warm up" effect in angina may represent ischaemic preconditioning, which is mediated by adenosine A(1) receptors in most models.

OBJECTIVE

To investigate the effect of a selective A(1) agonist, GR79236 (GlaxoSmithKline), on exercise induced angina and ischaemic left ventricular dysfunction in patients with coronary artery disease.

DESIGN

A double blind crossover study.

PATIENTS

25 patients with multivessel coronary artery disease.

INTERVENTIONS

On mornings one week apart, patients received intravenous GR79236 10 microgram/kg or placebo, and then carried out two supine bicycle exercise tests separated by 30 minutes. Equilibrium radionuclide angiography was done before and during exercise.

RESULTS

The onset of chest pain or 1 mm ST depression was delayed and occurred at a higher rate-pressure product during the second exercise test following either placebo or GR79236. Compared with placebo, GR79236 did not affect these indices during equivalent tests. GR79236 reduced resting global ejection fraction from (mean (SD)) 63 (7)% to 61 (5)% (p < 0.05) by a selective reduction in the regional ejection fraction of "ischaemic" left ventricular sectors (those where the ejection fraction fell during the first exercise test following placebo). Ischaemic sectors showed increased function during the second test following placebo (72 (21)% v 66 (20)%; p = 0.0001), or during the first test following GR79236 (69 (21)% v 66 (20)%; p = 0.0001). Sequential exercise further increased the function of ischaemic sectors even after drug administration.

CONCLUSIONS

GR79236 failed to mimic the warm up effect, and warm up occurred even in the presence of this agent. This suggests that ischaemic preconditioning is not an important component of this type of protection. The complex actions of the drug on regional left ventricular function at rest and during exercise suggest several competing A(1) mediated actions.

The homograft aortic valve: a 29-year, 99.3% follow up of 1,022 valve replacements

BACKGROUND AND AIM OF THE STUDY

The study aim was to elucidate the advantages and limitations of the homograft aortic valve for aortic valve replacement over a 29-year period.

METHODS

Between December 1969 and December 1998, 1,022 patients (males 65%; median age 49 years; range: 1-80 years) received either a subcoronary (n = 635), an intraluminal cylinder (n = 35), or a full root replacement (n = 352). There was a unique result of a 99.3% complete follow up at the end of this 29-year experience. Between 1969 and 1975, homografts were antibiotic-sterilized and 4 degrees C stored (124 grafts); thereafter, all homografts were cryopreserved under a rigid protocol with only minor variations over the subsequent 23 years. Concomitant surgery (25%) was primarily coronary artery bypass grafting (CABG; n = 110) and mitral valve surgery (n = 55). The most common risk factor was acute (active) endocarditis (n = 92; 9%), and patients were in NYHA class II (n = 515), III (n = 256), IV (n = 112) or V (n = 7).

RESULTS

The 30-day/hospital mortality was 3% overall, falling to 1.13 +/- 1.0% for the 352 homograft root replacements. Actuarial late survival at 25 years of the total cohort was 19 +/- 7%. Early endocarditis occurred in two of the 1,022 patient cohort, and freedom from late infection (34 patients) actuarially at 20 years was 89%. One-third of these patients were medically cured of their endocarditis. Preservation methods (4 degrees C or cryopreservation) and implantation techniques displayed no difference in the overall actuarial 20-year incidence of late survival endocarditis, thromboembolism or structural degeneration requiring operation. Thromboembolism occurred in 55 patients (35 permanent, 20 transient) with an actuarial 15-year freedom in the 861 patients having aortic valve replacement +/- CABG surgery of 92% and in the 105 patients having additional mitral valve surgery of 75% (p = 0.000). Freedom from reoperation from all causes was 50% at 20 years and was independent of valve preservation. Freedom from reoperation for structural deterioration was very patient age-dependent. For all cryopreserved valves, at 15 years, the freedom was 47% (0-20-year-old patients at operation), 85% (21-40 years), 81% (41-60 years) and 94% (>60 years). Root replacement versus subcoronary implantation reduced the technical causes for reoperation and re-replacement (p = 0.0098).

CONCLUSION

This largest, longest and most complete follow up demonstrates the excellent advantages of the homograft aortic valve for the treatment of acute endocarditis and for use in the 20+ year-old patient. However, young patients (< or = 20 years) experienced only a 47% freedom from reoperation from structural degeneration at 10 years such that alternative valve devices are indicated in this age group. The overall position of the homograft in relationship to other devices is presented.

The warm-up effect protects against ischemic left ventricular dysfunction in patients with angina

OBJECTIVES

The goal of this study was to investigate whether the "warm-up" effect in angina protects against ischemic left ventricular (LV) dysfunction.

BACKGROUND

After exercise, patients with coronary disease demonstrate persistent myocardial dysfunction, which may represent stunning, as well as warm-up protection against further angina, which may represent ischemic preconditioning. The effect of warm-up exercise on LV function during subsequent exercise has not been investigated.

METHODS

Thirty-two patients with multivessel coronary disease and preserved LV function performed two supine bicycle exercise tests 30 min apart. Equilibrium radionuclide angiography was performed before, during and up to 60 min after each test. Global LV ejection fraction and volume changes and regional ejection fraction for nine LV sectors were calculated for each acquisition.

RESULTS

Onset of chest pain or 1 mm ST depression was delayed and occurred at a higher rate-pressure product during the second exercise test. Sectors whose regional ejection fraction fell during the first test showed persistent reduction at 15 min (68 +/- 20 vs. 73 +/- 20%, p < 0.0001). These sectors demonstrated increased function during the second test (71 +/- 20 vs. 63 +/- 20%, p = 0.0005). The reduction at 15 min and the increase during the second test were both in proportion to the reduction during the first test. Effects on global function were only apparent when the initial response to exercise was considered.

CONCLUSIONS

The warm-up effect is accompanied by protection against ischemic regional LV dysfunction. The degree of stunning and protection after exercise is related to the severity of dysfunction during exercise, consistent with results from experimental models.

Aneurysms of an aberrant right subclavian artery: Report of two cases

Aneurysm of the aberrant right subclavian artery is rare. We report two patients who underwent successful repair using hypothermic circulatory arrest and retrograde cerebral perfusion. One patient presented with progressive dysphagia to solids and hoarseness of voice due to pressure exerted by the expanding aneurysm, and the second patient, with a dissected subclavian aneurysm, presented with transient ischaemic attacks and a previous cerebral infarct secondary to embolism. Repair in both patients was done through a median sternotomy with femoral arterial and right atrial venous cannulation. Under hypothermic circulatory arrest, the origin of the subclavian aneurysm was divided off the aorta and closed with a Dacron patch from outside the aorta in one patient, and from within the aorta in the other patient. Concomitant revascularisation of the right upper limb was achieved using a 12-mm Hemishield Dacron graft from the ascending aorta to the distal right subclavian artery. The graft to subclavian anastomosis was done under hypothermic circulatory arrest as distal control was not possible. The graft to the aortic anastomosis was done over a side-biting clamp during rewarming. Both patients were successfully treated without major morbidity.

The stentless xenograft aortic valve: The wheel turns around

BACKGROUND

A brief overview of the historical pathways of both stented and stentless porcine xenografts is presented in order to understand the return to and continuing clinical use of stentless devices. In addition, 7-11 years of durability with various models of stentless porcine valves has now accumulated and is beginning to be of relevance in determining the future place of this xenograft. Stentlessness and anticalcium agents, coupled with the poor results of stented xenografts in certain patient groups, have led to a resurgence of the clinical use of stentless xenograft valves for aortic valve replacement. An overview of the present state and future of stentless valves is given.

METHODS

At both The Prince Charles Hospital and St Andrew's War Memorial Hospital, Queensland, Australia, 307 patients have received the Model 300 CryoLife-O'Brien stentless composite aortic xenograft from December 1992 to February 2000. Associated procedures were required in 56% of patients (mostly coronary artery bypass, mean 2.4 grafts, in 144 patients (47%) and left ventricular myomectomy in 34 patients (11%)).

RESULTS

The hospital mortality (four early deaths) has been 1.3 +/- 1% (CL 95%) and the follow-up 100% for this analysis. The mean patient age was 73 years (range 57-89 years with 16% being 80 years and over). Morbid events have included six perivalvar leaks: four trivial and identified only on echo Doppler (no clinical murmurs) and two patients requiring reoperation at 10 days and 12 weeks with simple successful repair verified on subsequent echocardiograms. Of the 307 patients over the 7 year period, three valves only have been explanted, two for endocarditis at 1.5 and 3.5 years and one for possible technically induced structural failure at 15 months (probable needle damage). With this exception, there has been as yet no other intrinsic leaflet failure. Four early thromboembolic events (4 days-5 weeks) in patients with atrial fibrillation (no anticoagulants used postoperatively with the first 80 patients) constituted the important early morbid events. Late mortality of this elderly patient cohort has occurred in 27 patients over 7 years of maximum follow-up. One death (endocarditis) has been valve related at 5 years. Serial echocardiography (some 700 echoes in the study of this valve) has demonstrated a mean gradient of 7-9 mmHg with a very low incidence of trivial incompetence (96%) on Doppler examination with implant valve sizes ranging from 21 to 29 mm. One patient had significant regurgitation requiring reoperation. There has been no progression of either incompetence or stenosis of the remaining patients in this follow-up, now into the eighth postoperative year.

CONCLUSION

The early and intermediate results appear excellent in this elderly patient cohort. Nevertheless, important surveillance is obviously required to determine the durability at 10-12 years, a crucial time when stented porcine xenografts began to show an obvious failure rate from structural deterioration, in the middle and elderly aged patient cohort. An attempt is made to outline the future of this type of stentless xenograft and to justify that its cautious use should probably be extended down to the over 50 year age patient cohort.

Late complications of tissue glues in aortic surgery

BACKGROUND

Tissue glues are used in cardiothoracic surgery as an adjunct to operative procedures where tissues are frail, as in aortic dissection, or where added hemostasis is required. This study was undertaken to review the use of tissue glue in our institution over a 5.5-year period. The aim of the study was to identify any potentially glue-related complications.

METHODS

A review of tissue glue use for the period from January 1993 to September 1998 was performed and pre-, intra-, and postoperative parameters were collected. After some unusual surgical findings, of special interest was a range of pathology found at late reoperation.

RESULTS

A total of 67 cases of tissue glue use were identified, with the majority of operations for type A dissection (76%). There were two intraoperative deaths. Twenty-seven of 65 patients (41%) required 29 further open chest operations; of these, 17 were for acute problems of bleeding or tamponade. Twelve patients (18%) underwent late reoperations months to years later. Nine of these patients, concentrated in two operative groups (7 patients with aortic valve resuspension and 2 patients who had undergone "switch" operations for transposition of great vessels), displayed complications related to the application of gelatin-resorcinol-formaldehyde (GRF) tissue glue.

CONCLUSIONS

Indications for tissue glues in cardiothoracic surgery must be carefully considered. We have reviewed our use of some tissue glues in acute type A aortic dissections and in pediatric cardiac patients and have discontinued the use of GRF glues because of unsatisfactory long-term complications.

Exercise equilibrium radionuclide angiography predicts long-term cardiac prognosis in patients with abdominal aortic aneurysm being considered for surgery

BACKGROUND

Patients with an abdominal aortic aneurysm (AAA) have a high prevalence of coronary disease and are at risk for cardiac events. This may offset the prognostic benefit of surgical repair. We investigated whether preoperative exercise equilibrium radionuclide angiography (ERNA) could be used to identify patients at high risk for cardiac events after successful AAA repair.

METHODS

Between 1990 and 1995, 173 patients with an AAA were referred for supine bicycle exercise ERNA preoperatively. Follow-up information was obtained from a questionnaire sent to each patient's family physician. Cardiac events were defined as cardiac death or nonfatal myocardial infarction.

RESULTS

A total of 139 patients were able to exercise and did not die or suffer myocardial infarction perioperatively. The median follow-up period was 3.8 years. Diabetes mellitus, an exercise ejection fraction (EF) below 0.50, and a fall in EF with exercise were univariable predictors of cardiac risk during the follow-up period (P < .05). On multivariable analysis, diabetes mellitus (risk ratio [RR], 6.9; 95% CI 1.5 to 32.0) and an EF fall (RR, 4.1; 95% CI 1.5 to 11.4) emerged as the most important predictors.

CONCLUSIONS

Exercise ERNA predicts long-term cardiac events in patients being considered for elective AAA repair. Such predictive information may influence the decision to operate, for example, on small unthreatening aneurysms, or lead to invasive cardiological management to minimize risk.

The Cryolife-O'Brien stentless aortic porcine xenograft valve

BACKGROUND

The advantageous design of the Cryolife-O'Brien stentless porcine aortic valve permits specific quick, easy, supravalvular implantation using single layer continuous 3-0 polypropylene suture. The advantages, contraindications, and implantation errors to avoid are detailed. The use of this valve for aortic valve replacement in the elderly population has been directed to proving its efficacy and establishing its grounds for durability while maintaining all of the advantages of a stentless tissue valve.

METHODS

From December 1992 to September 1998, this valve was used in 240 patients (mean age 73 years: 15% > 80 years), 45% receiving associated coronary artery grafting (2.4 grafts per patient). Left ventricular (LV) myomectomy was necessary in 12% of patients. Detailed postoperative follow-up (100%) analysis included 650 serial echocardiographic studies.

RESULTS

The 30-day mortality was low at 1.2% (3 deaths of 240 elderly patients). Ten patients had late mortality (1.5 months to 5 years), all nonvalve related. No structural failure and one only explant for endocarditis have occurred. Echocardiographic analyses have shown low mean transvalvular gradients in relationship to time (8.18 mmHg at 18 months) and to valve size (8.52 mmHg for a 23-mm host aortic annulus). Incompetence has been zero or a trace in 97% of the patients at 21/2 years. No patient over the 6 years shows valve deterioration.

CONCLUSION

Six years of experience with this stentless valve in 240 elderly patients has revealed the many advantages of this safe, composite, and truly stentless device that is assembled without the need for Dacron support. Excellent sustained hemodynamics with low gradients, minimal regurgitation, and a good effective orifice have been coupled with low immediate mortality, no intrinsic valve failure, and one explant for endocarditis. Marked LV regression and minimal late valve-related complications confirm the safety and advantages of this stentless valve.

Allograft aortic valve replacement: long-term follow-up

Aortic valve replacement using an allograft aortic valve has been performed on 804 patients. From December 1969 to May 1975, 124 patients received a nonviable allograft valve sterilized by incubation with low-dose antibiotics and stored for weeks by refrigeration at 4 degrees C (series 1). From June 1975 to January 1994, 680 patients received viable allograft valves, now cryopreserved early within 2 hours of collection from transplant recipient donors, 6 hours for multiorgan donor valves and 23 hours (mean) for autopsy valves from donor death. The 30-day mortality was 8.9% +/- 5% (95% confidence limits) for series I and 2.8% +/- 1% (95% confidence limits) for series II. Actuarial patient survival including hospital mortality at 15 years was 56% +/- 5% for series I and 62% +/- 5% for series II. The probability of a thromboembolic event was low, freedom at 15 years being 95% +/- 1% for patients receiving allografts with or without associated coronary bypass procedures and 81% +/- 5% for patients having allografts with other associated procedures (eg, mitral valve operations). Actuarial freedom from endocarditis was similar for the two series, 91% +/- 3% (series I) and 94% +/- 2% (series II) at 15 years. The freedom from valve incompetence, from reoperation for all causes, and from structural deterioration demonstrated clearly the inferiority of the 4 degrees C stored allograft valves. For structural deterioration as identified clinically, at reoperation and at death, freedom from this event at 15 years was 45% +/- 6% for series I and 80% +/- 5% for series II (p value for the difference is 0).(ABSTRACT TRUNCATED AT 250 WORDS)

Root replacement for all allograft aortic valves: preferred technique or too radical?

From November 1985 to January 1994, 146 patients have received a viable cryopreserved allograft for aortic root replacement. The follow-up was complete, with all events included to March 1st, 1994. The median age of patients was 49 years; 83.6% were male. Valve dysfunction (91 patients), primary aortic wall disease (45 patients), and a combination of both (10 patients) were the indications for aortic root replacement. The current operative mortality is 1.7% (three deaths in 172 patients to July 1st, 1994). Four late deaths have occurred, with an 8-year actuarial survival of 85% +/- 8% (95% confidence limits). Endocarditis (two events) and thromboembolism (four events) had a low incidence. Structural deterioration (three events) and reoperation for all causes (nine events) have constituted low morbidity and are compared with the results after non-root allograft implantation techniques. The clinical and echocardiographic evidence indicates that the immediate results of valve function with root replacement are superior. But no statistical difference between aortic root replacement and non-root procedures is apparent at 8 years, indicating that a longer follow-up is required before the answer to the question "preferred technique or too radical" can be answered.

The Medtronic Intact xenograft: an analysis of 342 patients over a seven-year follow-up period

Three hundred forty-two patients from December 1985 to January 1993 received 352 Medtronic Intact porcine xenograft valves (zero-pressure glutaraldehyde-fixed with toluidine blue anticalcification agent). The follow-up was 99.4% complete with a mean of 3.14 years (3 months to 7.9 years). The mean patient age was 64 years (range, 16 to 82 years) and the median age was 67 years. There were 14 aortic valve replacement patients (11.9%) and 62 mitral valve replacement patients (29.2%) who preoperatively were in New York Heart Association class IV to V. The hospital mortality was 8.4% +/- 2.9% (aortic valve replacement, 5.9%; mitral valve replacement, 9.4%; tricuspid valve replacement, 7.6%). Actuarial patient survival at 7 years was 65% +/- 5% (aortic valve replacement, 77% +/- 5%; mitral valve replacement, 63% +/- 5%). At 7 years, the freedom from thromboembolism was 74% +/- 4%, freedom from endocarditis 93% +/- 2%, and freedom from reoperation 90% +/- 3%. Reoperation was required for endocarditis (7 patients), periprosthetic leak (6), and 2 of 3 cases of structural deterioration. The actuarial freedom from structural deterioration at 5 years was 97% +/- 3%. The combined incidence of all important morbid valve-related events was analyzed with an actuarial freedom at 7 years of 63% +/- 3%. The durability of the Medtronic Intact is at least equal to that of other porcine bioprostheses. The relevant important time-frame of 7 to 12 years of follow-up has just begun, and possibly the reoperation rate for intrinsic value failure and the low incidence of calcification in the elderly patient may be showing improved characteristics of this valve. No stronger inferences are possible at this stage of the 7-year follow-up.

An analysis of risk factors for death and mode-specific death after aortic valve replacement with allograft, xenograft, and mechanical valves

From September 1967 to January 1990, a total of 2100 patients underwent 2366 aortic valve replacements with a variety of allograft, xenograft, and mechanical valves. Concomitant procedures were performed in 764 patients. Actuarial survival at 12 years was 59.6% (70% confidence limits 57.8% to 61.4%). Hazard function for death was highest immediately after operation, falling to merge with a slowly rising phase of risk at approximately 3 months. Actuarial freedom from sudden death at 12 years was 88.0% (70% confidence limits 86.7% to 89.3%). The shape of the hazard function for sudden death was similar to that for death. Actuarial freedom from death with cardiac failure at 12 years was 87.9% (70% confidence limits 86.5% to 89.2%). The shape of the hazard function for death with cardiac failure was also similar to that for death. Risk factor analysis revealed the important deleterious impact on long-term survival resulting from impaired left ventricular structure and function because of aortic valve disease. No current-era valve used in this study (allograft, xenograft, or mechanical) was a risk factor for death. Both aortic wall disease and endocarditis necessitating aortic valve replacement substantially decreased long-term patient survival. Aortic valve replacement is advisable much earlier in the natural history of aortic valve disease before secondary left ventricular damage occurs.

Aortic valve infection. Risk factors for death and recurrent endocarditis after aortic valve replacement

Patients (n = 195) undergoing aortic valve replacement (n = 209) for native or prosthetic valve endocarditis were studied to determine risk factors for death and recurrent endocarditis and also to determine the valve type least likely to be associated with recurrent endocarditis. Ten-year survival was 60%, the highest risk of dying occurring within the first 3 postoperative months. Risk factors for death in this early phase included increased urea concentration, higher New York Heart Association functional class, prosthetic valve endocarditis, infection status (lower in patients with healed endocarditis), longer duration of cardiopulmonary bypass, and nonuse of an allograft valve. In the late phase (beyond 3 months), risk factors included age at operation and Staphylococcus aureus infection (only in New York Heart Association functional class V). Ten years after aortic valve replacement, 79% of valves were free of recurrent endocarditis. The highest risk of recurrence was in the first 4 months. Longer duration of cardiopulmonary bypass was a weak risk factor for recurrent endocarditis in the early phase, and in the late phase risk factors were S. aureus infection (only in New York Heart Association functional classes III, IV, and V) and the use of now discontinued biologic valves. Allograft aortic valve replacement was shown to be associated with a low and constant risk of recurrent endocarditis, whereas other valve types were associated with a high early risk. The allograft valve should be the preferred replacement device for aortic root infection.

Allograft aortic valve replacement: long-term comparative clinical analysis of the viable cryopreserved and antibiotic 4 degrees C stored valves

Aortic valve replacement with or without concomitant procedures was performed using an allograft aortic valve in 534 patients. From December 1969 to May 1975 (group I), a 4 degrees C stored valve was used (124 patients) and from June 1975 to July 1990 (group II), a cryopreserved valve (410 patients) was used. The 30-day mortality was 8.9% (confidence limits [CL] 6.2%-12.3%) for group I and 2.7% (CL 1.9%-3.8%) for group II. Actuarial patient survival including early hospital mortality at 14 years was 57% for group I and 71% for group II (p = 0.014). Actuarial freedom from thromboembolism for all patients (n = 534) was 94% at 14 years, and for patients who underwent isolated aortic valve replacement with or without coronary artery bypass graft (n = 457) was 97% at 14 years (p = 0.017). Actuarial freedom from allograft valve endocarditis at 14 years was 92% in group I and 94% in group II (p = 0.36). The actuarial freedom from moderate or severe allograft valve incompetence at 14 years was 50% (group I) and 78% (group II) (p = 0.27). Reoperation was undertaken for endocarditis, leaflet structural deterioration (SD), or technical reasons. The actuarial freedom from reoperation (all causes) at 14 years was 63% (group I) and 86% (group II) (p = 0.39). Reoperation for SD occurred in 34 patients in group I and three patients in group II. The actuarial freedom from reoperation for SD at 14 years was 67% (group I) and 95% (group II) (p = 0.001). To reflect a more accurate depiction of the prevalence of SD, patients were analyzed according to the development of "assumed structural deterioration" (at reoperation, at death with moderate or severe allograft valve incompetence and macroscopic valve deterioration on autopsy, and in the presence of moderate or severe allograft valve incompetence in patients not undergoing reoperation). The actuarial freedom from "assumed structural deterioration" at 14 years was 51% (group I) and 85% (group II) (p = 0.000003). The long-term results confirm the low incidence of thromboembolism and endocarditis regardless of the method of preservation and demonstrate the overall acceptable performance of the viable cryopreserved allograft valve and its superiority over the 4 degrees C stored valve.

Surgical intervention for drug-resistant ventricular tachycardia

Endocardial resection was required in 26 patients with sustained drug-resistant ventricular tachycardia. The early mortality rate (within 30 days after operation) was 12%. Two deaths were the result of low cardiac output, and the third death was related to recurrent ventricular septal defect after septal endocardial resection. The survivors of endocardial resection were followed up from 6 to 92 months (mean 43). There were no recurrences of ventricular arrhythmias, and patients did not require antiarrhythmic drug therapy. The late mortality rate after endocardial resection was 19%. There were two late cardiac-related deaths (unrelated to arrhythmias) and three late deaths from noncardiac causes. Complete endocardial resection successfully ablates drug-resistant ventricular tachycardia, but is associated with an increased perioperative mortality rate in those patients who have severely depressed left ventricular function without a well defined left ventricular aneurysm.

Intramural haematoma of the oesophagus complicated by perforation

A case is presented where spontaneous bleeding into the wall of the oesophagus was exacerbated by anticoagulant therapy. Subsequently, iatrogenic, full-thickness perforation of the oesophagus occurred during endoscopy and, ultimately, oesophagectomy was required. If this condition is suspected on clinical grounds, the most appropriate sequence of investigations would appear to be contrast radiography in the first instance with cautious use of oesophagoscopy.

Long-term results of the viable cryopreserved allograft aortic valve: continuing evidence for superior valve durability

From December 1969 to May 1975, 124 patients underwent aortic valve replacement with an allograft aortic valve sterilized by incubation in a low dose antibiotic solution and stored by refrigeration at 4 degrees C (4 degrees C stored valve group). From June 1975 to December 1987, 231 patients received an allograft aortic valve, sterilized by the same low dose antibiotic solution, but stored by cryopreservation in liquid nitrogen at -196 degrees C (cryopreserved valve group). The 4 degrees C stored valves were essentially nonviable, whereas the cryopreserved valves were viable at implantation. Of the 355 aortic valve replacements, associated procedures were performed in 127 patients. The 30-day mortality was 8.9% (confidence limits [C.L.] 6.2% ... 12.3%) (4 degrees C stored) and 4.8% (C.L. 3.3% ... 6.7%) (cryopreserved). Actuarial survival was similar in both groups, being 71% and 67% at 10 years in the 4 degrees C stored and cryopreserved valve groups, respectively (P = .18). The probability of a thromboembolic event was low, but appeared higher in the 4 degrees C stored valve group (actuarial freedom at 10 years, 90%) than the cryopreserved valve group (actuarial freedom at 10 years, 98%) (P = .01) probably related to associated mitral valve surgery. The actuarial freedom from allograft valve endocarditis at 10 years was 94% and 95% for the 4 degrees C stored and cryopreserved valve groups, respectively (P = .23). Reoperation was undertaken in 34 patients in the 4 degrees C stored group and 12 patients in the cryopreserved valve group for leaflet degeneration, endocarditis, or technical reasons.(ABSTRACT TRUNCATED AT 250 WORDS)

A comparison of aortic valve replacement with viable cryopreserved and fresh allograft valves, with a note on chromosomal studies

We examined the long-term clinical function and fate of allograft aortic valves, preserved by two differing methods, for aortic valve replacement: (1) fresh allografts stored at 4 degrees C refrigeration (group I) and (2) viable allografts cryopreserved in liquid nitrogen at -196 degrees C (group II). A total of 316 aortic valve replacement operations were performed, 124 in group I (December 1969 to May 1975) and 192 in group II (June 1975 to December 1986). Concomitant surgical procedures (eg, coronary artery bypass grafting and mitral valve replacement) were necessary in 120 operations. The overall immediate 30 day mortality was 6.0% (confident limits 4.6% to 7.7%), and the survival rates were 83% at 4 years and 60% at 15 years. Endocarditis and technical factors concerning reoperation showed no difference between the two groups according to parametric estimates and hazard function analyses. However, there was a marked difference in reoperation for valve degeneration: 23 patients in group I and 0 patients in group II. The freedom from reoperation for valve degeneration at 10 years was 89% for group I and 100% for group II, and at 15 years it was 59% for group I. The hazard function for group I reflected the late rising risk of degeneration. The freedom from thromboembolism of both groups (aortic valve replacement with or without bypass grafting) was 97% at 10 years and 96% at 15 years. Group II explanted valves (operation for technical malalignment reasons) has consistently shown evidence of persisting viability on tissue culture, on metabolic studies, and on histologic appearances. Chromosomal studies have shown the donor origin of these cells. The superior results with the cryopreserved valve is considered to be due to persisting viability, which appears to be the key to durability.

Intrathoracic great vessel injury resulting from blunt chest trauma associated with posterior dislocation of the sternoclavicular joint

Three cases of great vessel injury resulting from blunt chest trauma and associated with posterior dislocation of the sternoclavicular joint are presented. The diagnosis and management including the surgical approach to this uncommon injury are discussed.

Pulmonary metastatic chondrosarcoma with intracardiac extension

An unusual case of pulmonary metastatic chondrosarcoma with intracardiac extension is presented. Echocardiography and right heart catheterization with pulmonary angiography demonstrated that resection using cardiopulmonary bypass was possible in a situation initially considered to be inoperable.

Bronchobiliary fistula due to hydatid disease: a case report

A case of bronchobiliary fistula due to transdiaphragmatic rupture of hepatic echinococcal cyst is described. The importance of excluding associated extrahepatic biliary obstruction is emphasized. Successful treatment involves relief of this obstruction as well as management of both the pleural space and pulmonary complications.

Chronic cough and haemoptysis due to a nematode, "Syngamus laryngeus"

A case of bronchial infection with Syngamus laryngeus (Gapeworm) in a 42-year-old woman is described. Following presentation with chronic cough, haemoptysis and weight loss, a pair of worms was removed at bronchoscopy, with resolution of symptoms.

Management of concomitant occlusive disease of the carotid and coronary arteries

With the advent of direct coronary artery revascularization, the high mortality rate from cardiac disease associated with carotid endarterectomy can be favorably altered by simultaneous or staged revascularization for combined lesions. The choice for combined or sequential procedures is determined by the severity of the disease both clinically and anatomically in each system. Review of 32 patients with both severe coronary and carotid occlusive disease established that selective surgical intervention has been successful, with no deaths and only minimal morbidity. Simultaneous revascularization was carried out in 8 patients with preinfarctional angina, significant left main lesion or triple vessel disease producing a functional lesion of the left main coronary artery, and tight carotid lesion. Staged operations were performed in the remaining 24 patients. Priority of staging was determined by the extent of disease in each system.

Mediastinoscopy

A series of 150 mediastinoscopic examinations, performed at The Prince Charles Hospital, Brisbane, is reported. The procedure was employed as a diagnostic aid in the care of patients known to be suffering from disease processes involving the superior mediastinum, and as a preoperative assessment in a group of patients known to have, or suspected of having, bronchogenic carcinoma, There was no mortality. The morbidity rate was 2%.

Immunodiagnosis of a metastasis in a patient with a history of double malignant disease

This paper discusses the use made of the antigenic specificity of malignant tumours in the diagnosis and subsequent management of a patient with secondary malignant disease who had previously been treated for both carcinoma of the breast and malignant melanoma. A comparatively simple, rapid test (leucocyte adherence inhibition) was used to determine the patient's antitumour immunoreactivity. Cell-mediated immunity against both types of tumour was detected, but this was accompanied by serum-blocking factor corresponding to melanoma only, which indicated that the secondary malignant disease was melanoma.