Potential of radiomics analysis and machine learning for predicting brain metastasis in newly diagnosed lung cancer patients

AIM

To explore the potential of utilising radiomics analysis and machine-learning models that incorporate intratumoural and peritumoural regions of interest (ROIs) for predicting brain metastasis (BM) in newly diagnosed lung cancer patients.

MATERIALS AND METHODS

The study comprised 183 lung cancer patients (training cohort: n=146; validation cohort: n=37) whose radiomics features were extracted from plain computed tomography (CT) images of the primary lesion. Four machine-learning algorithms (logistic regression [LR], support vector machine [SVM], k-nearest neighbour algorithm [KNN], and random forest [RF]) were employed to develop predictive models. Model diagnostic performance was assessed through receiver operating characteristic (ROC) analysis, and clinical utility was evaluated using decision curve analysis (DCA). Finally, the radiomics model's generalisation ability was further validated in the prediction of metachronous brain metastasis (MBM).

RESULTS

After feature screening, 22 radiomics features were identified as highly predictive, of which nine were derived from the peritumour region. All four machine-learning models demonstrated predictive capability, with SVM showing superior efficiency and robustness. The area under the ROC curve (AUC) of SVM was 0.918 in the training cohort and 0.901 in the validation cohort. DCA indicated the highest net benefit. Furthermore, the time-dependent ROC curve exhibited predictive efficacy for MBM occurrence across 1-, 2-, and 3-year follow-up periods, with all AUC values exceeding 0.7.

CONCLUSION

The optimal SVM model integrating intratumoural and peritumoural radiomics features was confirmed and defined as an imaging biomarker for predicting BM in newly diagnosed lung cancer patients, underscoring its potential to significantly impact clinical diagnosis and treatment.

Carbonic anhydrases III and IX are new players in the crosstalk between adrenocortical carcinoma and its altered adipose microenvironment

PURPOSE

Adrenocortical carcinoma (ACC), a rare malignancy of the adrenocortex, is characterized by a crosstalk between the adipose microenvironment and tumor. Here, we assessed the involvement of carbonic anhydrase (CA) enzymes III and IX (CAIII and CAIX), in the metabolic alterations of the adipose tissue characterizing obesity and in the local crosstalk between the tumor adipose microenvironment and ACC.

RESULTS/METHODS

CAIII and CAIX expression is altered in visceral adipose tissue (VAT) in obesity and in ACC. A significant CAIX upregulation was present in ACC at advanced stages (n = 14) (fold increase FI = 7.4 ± 0.1, P < 0.05) associated with lower CAIII levels (FI = 0.25 ± 0.06, P < 0.001), compared with lower stages (n = 9). In vitro coculture between visceral adipose stem cells (ASCs) and ACC cell lines, H295R and MUC-1, mimicking the interaction occurring between VAT and advanced ACC, showed a significant CAIX upregulation in H295R but not in MUC-1 cells, and a decreased expression of CAIII. The effect on adipose cells was different when cocultured with H295R or MUC-1 cells. Coculture did not modulate CAIII expression in ASCs, which, however, was significantly downregulated with H295R (FI = 0.34 ± 0.11, P < 0.05) and upregulated by MUC-1 when cocultured ASCs were induced to differentiate toward adipocytes, with an expression profile similar to what found in VAT of obese subjects. CAIX expression was markedly increased in ASCs cocultured with H295R and to a less extent following adipogenesis induction (FI = 150.9 ± 46.5 and FI = 4.6 ± 1.1, P < 0.01, respectively).

CONCLUSION

Our findings highlight a modulation of CAIII and CAIX in the metabolic crosstalk between ACC and its local adipose microenvironment, suggesting that CAs might represent a potential target for novel anticancer therapies.

Crosstalk reduction in a piezoelectric phononic plate induced by electrical boundary conditions: Application to multi-element transducers

This paper proposes a method of passive electrical decoupling which aimed at found application in reducing the crosstalk phenomenon in multi-element ultrasonic transducers. A homogeneous piezoelectric plate, covered on one side by a 1D periodic arrangement of thin metallic electrodes and on the other side by a full electrode, is considered. Finite element analysis and experimental measurements are performed to obtain the dispersion curves and normal displacements at the surface of the structure. It is shown that applying inductive shunts at the electrodes, band gaps can be created in the first Brillouin zone, which can prevent from the establishment of the first thickness mode in the plate. In that way the mechanical inter-element coupling can be lowered. Thus, the acoustic radiation in water from one sector excited at the resonance frequency is found to be closer to that of a piston mode. The transposition of this principle to the situation of a transducer including a rear medium and a front matching layer confirms the possibility of reducing the inter-element coupling. However, the physical effects at the origin of this reduction are different from those inherent to the cutting of a piezocomposite ceramic as it is done in most probes available in the market. As a result, we show that taking advantage of the electrical boundary conditions upon the passive elements in a transducer gives real opportunities for crosstalk reduction that may be implemented in ultrasonic systems for imaging in the medical field and in NDT.

Acute cardiac injury and acute kidney injury associated with severity and mortality in patients with COVID-19

OBJECTIVE

To determine the incidence and risk factors for acute cardiac injury (ACI) and acute kidney injury (AKI), and then investigate their effect on severity and mortality in patients with COVID-19.

PATIENTS AND METHODS

A total of 1249 patients with COVID-19 were included in this retrospective study. Predictors of ACI and AKI were investigated. Multivariable-logistic regression models were used to determine the association of ACI (or AKI) with severity and mortality.

RESULTS

Median age of patients was 36 years and 61.9% were male. ACI and AKI were observed in 53 (4.2%) and 91 (7.3%) of patients, respectively. Patients with age > 60 years, chronic heart disease, decreased lymphocyte and increased CRP, PCT, and ESR on hospital admission, and Lopinavir/Ritonavir use showed higher odds of ACI. Patients with age > 60 years, male, obesity, hypertension, chronic kidney disease, decreased lymphocyte and increased CRP, PCT, and ESR on hospital admission showed higher odds of AKI. Increased Hs-cTnI (> 300 ng/L), Pro-BNP (> 2500 pg/ml) and decreased e-GFR (< 60 ml/min) revealed higher adjusted mortality.

CONCLUSIONS

ACI and AKI were not common in COVID-19 patients in Shanghai, China. However, patients with ACI/AKI had higher severity-rate and mortality-rate when compared to those without ACI/AKI.

The clinical impact of serum sLOX-1 level in coronary artery disease patients as inferred from its implication in the in vitro protective effects of metoprolol against hypoxic injury of HUVECs

Background

Ischemic coronary artery disease (CAD) is a major public health problem across the world. Early detection and appropriate management significantly reduced CAD-induced morbidities and death. Endothelial cells are pathogenically implicated.

Purpose

Our study was designed to investigate the role of the soluble lectin-like oxidized low-density lipoprotein receptor-1 (sLOX-1) in the in vitro protective effect of Metoprolol against hypoxia-induced injury of Human umbilical vein endothelial cells (HUVECs). Secondly, the clinical significance of variations in serum levels of sLOX-1 in patients with CAD was assessed.

Methods

In vitro, hypoxic injury model of HUVECs was established in an atmosphere of 1% O2, 95% N2, and 5% CO2 for 24 hours. The protective effect and mechanism of action of the cardio-selective beta-blocker Metoprolol at 10–6 μM concentration was investigated.

Consented stable atherosclerotic CAD (n=150) and unstable angina pectoris patients (n=75) along with 150 healthy volunteer subjects were voluntarily enrolled in this ethically approved study. Invasive coronary angiogram with ≥50% stenosis at least in one major coronary artery was used for diagnosis. ESC/ACC/AHC/practical protocols were used for categorizing patients into stable or unstable CAD. Serum sLOX-1 level was measured using specific ELISA kit. The diagnostic significance of serum sLOX-1 levels was assessed by analyzing its area under the curve (AUC).

Results

In vitro hypoxic conditions induced high rate of cellular apoptosis, high levels of LOX-1 expression, reactive oxygen species (ROS) generation and LDH release from HUVECs after 24 hours incubation, compared to normoxic control cells. Metoprolol significantly decreased LOX-1 levels, and prevented the release of LDH and generation of ROS. This culminated into marked improvement in cellular viability of hypoxia-exposed HUVECs (p&lt;0.001).

Compared to healthy subjects, serum levels of sLOX-1s were significantly elevated in atherosclerotic stable and unstable CAD patients (p&lt;0.001). Serum sLOX-1 levels were increased by 4.21 folds in stable CAD patients and by 6.373 folds in atherosclerotic unstable angina patients vs. healthy participants. Moreover, the levels in the two patients' groups were significantly different (p&lt;0.001). In stable angina CAD patients, sLOX-1 AUC = 0.929; and in unstable CAD patients, AUC = 0.944, indicating that serum sLOX-1 levels clearly differentiated patients from healthy participants with high specificity and sensitivity.

Conclusions

Extrapolated from HUVECs hypoxia-induced injury model and the protective effect of Metoprolol, elevation of the circulating levels of sLOX-1 correlated with increased risks for atherosclerotic CAD and is a highly sensitive and specific biomarker for early detection of the disease.

Funding Acknowledgement

Type of funding source: None

Hepatic Hilar Lymph Node Reactivity at Kasai Portoenterostomy for Biliary Atresia: Correlations With Age, Outcome, and Histology of Proximal Biliary Remnant

We hypothesized that if infection is the proximate cause of congenital biliary atresia, an appropriate response to antigen would occur in lymph nodes contiguous with the biliary remnant. We compared the number of follicular germinal centers (GC) in 79 surgically excised hilar lymph nodes (LN) and 27 incidentally discovered cystic duct LNs in 84 subjects at the time of hepatic portoenterostomy (HPE) for biliary atresia (BA) to autopsy controls from the pancreaticobiliary region of non-septic infants >3 months old at death. All 27 control LN lacked GC, a sign in infants of a primary response to antigenic stimulation. GC were found in 53% of 106 LN in 56 of 84 subjects. Visible surgically excised LN contiguous with the most proximal biliary remnants had 1 or more well-formed reactive GC in only 26/51 subjects. Presence of GC and number of GC/LN was unrelated to age at onset of jaundice or to active fibroplasia in the biliary remnant but was related to older age at HPE. Absent GC in visible and incidentally removed cystic duct LNs predicted survival with the native liver at 2 and 3 years after HPE, P = .03, but significance was lost at longer intervals. The uncommon inflammatory lesions occasionally found in remnants could be secondary either to bile-induced injury or secondary infection established as obstruction evolves. The absence of consistent evidence of antigenic stimulation in LN contiguous with the biliary remnant supports existence of at least 1 major alternative to infection in the etiology of biliary atresia.

Rosiglitazone Attenuates Memory Impairment in Aged Rat with Diabetes by Inhibiting NF-kappa B Signal Pathway Activation

Although the cognitive impairment in geriatric diabetes is common, its mechanisms remain unclear and therapies are limited. The present study investigated the effects of rosiglitazone on memory impairment in aged rats with diabetes. Diabetes was induced by streptozotocin in aged Wistar rats of 20-22 months. Then, the diabetic rats were divided randomly into the diabetic model group and rosiglitazone treatment group for assessment of cognitive function and cerebral injury at 8 weeks using Morris water maze (MWM) paradigm, real-time PCR and western blot analysis. Wistar rats of the same age were also assessed as control. In vitro, the therapeutic effect of rosiglitazone was investigated using rat chromaffin cell line PC12 cultured with high glucose and/or C-reactive protein (CRP). 8 weeks after diabetes induction aged rats exhibited marked and persistent hyperglycemia, weight loss, higher level of serum CRP and learning impairments. Enhanced cerebral inflammation in aged rats with diabetes was associated with over-activation of the nuclear factor κB (NF-κB) signalling pathway and upregulation of inflammatory cytokines (IL-6, TNFα) in the hippocampus. Compared with the diabetic group, level of serum CRP, inflammatory cytokines and over-activation of NF-κB signalling pathway in the hippocampus were restored partially concomitant with attenuation of cognitive dysfunction indicated as markedly decreased escape latency and distance during MWM test in the rosiglitazone treatment group. In vitro, high glucose significantly activated NF-κB signalling pathway and upregulated inflammatory cytokines. CRP synergistically promoted high glucose-mediated effects. Rosiglitazone significantly ameliorated the effects mediated by high glucose and CRP.These effects were significantly reversed by co-treatment with the PPARγ antagonist T0070907. These results suggest that rosiglitazone can improve cognitive function in aged rats with diabetes by inhibiting the NF-κB signal activation and decreasing the expressions of inflammatory cytokines in the hippocampus.

Epiphrenic diverticula mini-invasive surgery: a challenge for expert surgeons--personal experience and review of the literature

BACKGROUND AND AIMS

While in the past, thoracotomy represented the traditional surgical approach for the treatment of epiphrenic diverticula, actually mini-invasive approach seems to be the preferred treatment as many series have been published in the recent years. This article describes the authors' experience with the laparoscopic approach for performing diverticulectomy, myotomy, and Nissen-Rossetti fundoplication.

MATERIAL AND METHODS

From 1994 to 2010, 21 patients (10 men and 11 women), mean age 58.5 years (range 45-74 years), with symptomatic epiphrenic diverticulum underwent laparoscopic diverticulectomy, myotomy and Nissen-Rossetti fundoplication.

RESULTS

The mean operative time was 135 min (range = 105-190 min). Mean hospital stay was 14.2 days (range = 7-25 days). In 5 patients (23.8%), a partial suture staple line leak was observed. Conservative treatment achieved leak resolution in all the cases. One patient (4.8%) died of a myocardial infarction in the postoperative period. After a mean clinical follow-up period of 78 months (range = 6-192 months), excellent or good outcome was referred with no dysphagia in 16 patients (80%) and only mild occasional dysphagia in 4 patients (20%).

CONCLUSIONS

Surgical treatment of epiphrenic diverticula remains a challenging procedure also by mini-invasive approach, with major morbidity and mortality rates. For this reason, indications must be restricted only to selected and symptomatic patients in specialized centers.

Quadrimembral amputation: indications and contraindications for vascularized composite allotransplantation

INTRODUCTION

Quadrimembral amputees, as patients who have lost both upper and lower extremities, may benefit greatly from hand transplantation. The objective of this study is to evaluate the indications and contraindications for transplantation in this subset of patients.

METHODS

A retrospective review was conducted of five quadrimembral amputees evaluated by our program for transplantation. Information collected included age, sex, level of amputations, time since amputations, etiology, level of dependence, medical stability, psychosocial status, and the ability to tolerate immunosuppression. Indications and contraindications for transplantation were reviewed for each patient.

RESULTS

All etiologies were based in extremity ischemia: three from septic shock, one from myocardial infarction, and one from drug overdose. All patients are completely dependent. Of the five patients, two needed further reconstructive surgery and two others had a history of resolved hepatic/renal insufficiency. After thorough evaluation, two patients were selected as potential transplant candidates. They demonstrated strong psychosocial support systems, a thorough understanding of hand transplantation, along with its risks and postoperative requirements. They had also completed a full regimen of rehabilitation along with prosthetic fitting and utilization.

CONCLUSIONS

Clearance for transplantation is based on medical stability, absence of infection or systemic diseases, and strong psychosocial support systems. Contraindications for transplantation are drug dependence and noncompliant behavior. Relative contraindications include a history of hepatic/renal insufficiency which if not resolved may preclude the use of postoperative immunosuppression.

Effect of preoperative chemoradiotherapy on outcome of patients with locally advanced esophagogastric junction adenocarcinoma-a pilot study

BACKGROUND

To date, few studies of preoperative chemotherapy or chemoradiotherapy (crt) in gastroesophageal junction (gej) cancer have been statistically powered; indeed, gej tumours have thus far been grouped with esophageal or gastric cancer in phase iii trials, thereby generating conflicting results.

METHODS

We studied 41 patients affected by locally advanced Siewert type i and ii gej adenocarcinoma who were treated with a neoadjuvant crt regimen [folfox4 (leucovorin-5-fluorouracil-oxaliplatin) for 4 cycles, and concurrent computed tomography-based three-dimensional conformal radiotherapy delivered using 5 daily fractions of 1.8 Gy per week for a total dose of 45 Gy], followed by surgery. Completeness of tumour resection (performed approximately 6 weeks after completion of crt), clinical and pathologic response rates, and safety and outcome of the treatment were the main endpoints of the study.

RESULTS

All 41 patients completed preoperative treatment. Combined therapy was well tolerated, with no treatment-related deaths. Dose reduction was necessary in 8 patients (19.5%). After crt, 78% of the patients showed a partial clinical response, 17% were stable, and 5% experienced disease progression. Pathology examination of surgical specimens demonstrated a 10% complete response rate. The median and mean survival times were 26 and 36 months respectively (95% confidence interval: 14 to 37 months and 30 to 41 months respectively). On multivariate analysis, TNM staging and clinical response were demonstrated to be the only independent variables related to long-term survival.

CONCLUSIONS

In our experience, preoperative chemoradiotherapy with folfox4 is feasible in locally advanced gej adenocarcinoma, but shows mild efficacy, as suggested by the low rate of pathologic complete response.

Long-term function of parathyroid subcutaneous autoimplantation after presumed total parathyroidectomy in the treatment of secondary hyperparathyroidism. A clinical retrospective study

INTRODUCTION

Parathyroidectomy (PTx) is recommended in patients affected by secondary hyperparathyroidism (2HPT) of chronic kidney disease-mineral bone disorders (CKD-MBD), resistant to medical treatment. Analyzing total parathyroidectomy with muscular or subcutaneous autoimplantation (TPai) outcomes in hemodialysis (HD) 2HPT patients, and monitoring intact parathyroid hormone (iPTH) levels, we evaluated long-term functional results of subcutaneous parathyroid glandular tissue autoimplantation.

METHODS

40 HD 2HPT patients, resistant to medical treatment, and awaiting for renal transplantation, underwent total parathyroidectomy with subcutaneous autoimplantation of 9-12 fragments of not nodular hyperplasia parathyroid tissue in not dominant forearm. iPTH were analyzed 24 h, and 3-6-12-24 months after surgery. The 1.08-6.99 pmol/L range was taken as reference of normal iPTH level based on which eu- (1.08-6.99), hypo- (<1.08), aparathyroidism (0) and persistence or relapse (>6.99) of disease were determined.

RESULTS

In every case PTai determined an extraordinary improvement of quality of life, associated with a notable reduction of iPTH serum level. Immediate normalization of iPTH was achieved in 50% of cases; hypoparathyroidism in 25% of cases and persistence of disease in 25% were observed. Long term follow-up showed a reduction of hypoparathyroidism and an increase of relapse rate up to 20%. Grafting resection was never performed.

DISCUSSION

Subcutaneous autotrasplantation is a very simple and fast surgical technique. Nevertheless, similar success and recurrence rates were reported following muscular or subcutaneous grafting, as confirmed in our experience.

CONCLUSIONS

Subcutaneous grafting was effective as muscular implantation, with comparable functional results, but avoiding its potential complications.

Feasibility and effectiveness of primary umbilical hernia repair with biologic graft: preliminary study

BACKGROUND

In this prospective non-randomized observational cohort study we evaluated: the feasibility and effectiveness of primary umbilical hernia repair with open tension-free and sutureless technique using a porcine small intestinal submucosa (Surgisis) prosthesis, the quality of the treatment in terms of reduction of postoperative discomfort and the complications at early and long-term follow-up.

METHODS

Thirty-six consecutive patients, mean age 45.25 +/- 12.19 years, affected by primary umbilical uncomplicated hernia with a defect size < or = 3 cm, were treated in a day-surgery setting. A tailored flat Surgisis graft was used to ensure an overlap of at least 2 cm; in all patients the mesh was fixed by fibrin glue. Collected data included: visual analogic scale (VAS) pain scores at 24 hours, 72 hours, and 7, 15, and 30 days and number of analgesic medications after operation, complications rate, the quality of life measured by Short Form 36 health survey questionnaire (SF-36) before the operation and at long term follow-up.

RESULTS

The mean follow-up time was 5.6 +/- 1.4 years. Postoperative pain was low: the mean visual analogic scale (VAS) scores were 2.8 at 24 h, 1.8 at 72 h, and 0.9, 0.3, and 0.04 at 7, 15, and 30 days, respectively. 77.8% of the patients (28/36) did not use any analgesic drugs. Seroma was reported in 13.8% of the patients (5/36); there were no hematomas, infection, chronic pain and no major complications or mortality (< or = 30 days). Recurrence rate was 2.8% (1/36). Patient satisfaction showed a significant improvement in all SF-36 domain scores (P < 0.001).

CONCLUSIONS

The biologic mesh seems to be a safe and reliable device for repairing primary umbilical hernia with high patient comfort, even if not yet an alternative to synthetic mesh.

A case of extraovarian primary peritoneal carcinoma in an oophorectomized-hysterectomized patient: a diagnostic dilemma

Extra Ovarian Primary Peritoneal Carcinoma (EOPPC) is a rare type of adenocarcinoma of the pelvic and abdominal peritoneum. The objective examination and the histological aspect of the neoplasia virtually overlaps with that of ovarian carcinoma. The reported case is that of a 72 year-old patient who had undergone a total hysterectomy with bilateral annessiectomy surgery 20 years earlier subsequently to a diagnosis for uterine leiomyomatosis. The patient came to our attention presenting recurring abdominal pain, constipation, weight loss, severe asthenia and fever. Her blood test results showed hypochromic microcytic anemia and a remarkable increase CA125 marker levels. Instrumental diagnostics with Ultrasound (US) and CT scans indicated the presence of a single peritoneal mass (10-12 cm diameter) close to the great epiploon. The patient was operated through a midline abdominal incision and the mass was removed with the great omentum. No primary tumor was found anywhere else in the abdomen and in the pelvis. The operation lasted approximately 50 minutes. The post-operative course was normal and the patient was discharged four days later. The histological exam of the neoplasia, supported by immunohistochemical analysis, showed a significant positivity for CA 125, vimentin and cytocheratin, presence of psammoma bodies, and cytoarchitectural pattern resembling that of a serous ovarian carcinoma even in absence of primitiveness, leading to a final diagnosis of EOPPC. The patient later underwent six cycles of chemotherapy with paclitaxel (135 mg/m²/24 hr) in association with cisplatin (75mg/m²). At the fourth year follow-up no sign of relapse was observed.

Sequence variation and genetic diversity in the giant panda

About 336-444 bp mitochondrial D-loop region and tRNA gene were sequenced for 40 individuals of the giant panda which were collected from Mabian, Meigu, Yuexi, Baoxing, Pingwu, Qingchuan, Nanping and Baishuijiang, respectively. 9 haplotypes were found in 21 founders. The results showed that the giant panda has low genetic variations, and that there is no notable genetic isolation among geographical populations. The ancestor of the living giant panda population perhaps appeared in the late Pleistocene, and unfortunately, might have suffered bottleneck attacks. Afterwards, its genetic diversity seemed to recover to some extent.

Open tension-free Lichtenstein repair of inguinal hernia: use of fibrin glue versus sutures for mesh fixation

PURPOSE

To investigate pain and other complications following inguinal hernioplasty performed by the Lichtenstein technique with mesh fixation by fibrin glue or sutures.

METHODS

Five hundred and twenty patients were enrolled in this 12-month observational multicenter study and received either sutures or fibrin glue (Tissucol(®)/Tisseel(®)) based on the preference of the surgeon. Pain, numbness, discomfort, recurrence, and other complications were assessed postoperatively and at 1, 3, 6, and 12 months. Pain intensity was assessed by a visual analog scale (VAS; 0 [no pain] to 10 [worst pain]).

RESULTS

One hundred and seventy-one patients received sutures and 349 received fibrin glue. During the early postoperative phase, 87.4% of patients in the fibrin glue group and 76.6% of patients in the sutures group were complication-free (P = 0.001). Patients who received fibrin glue were also less likely to experience hematoma/ecchymosis than those in the suture group (both P = 0.001). The mean pain score was significantly lower in the fibrin group than the sutures group (2.5 vs. 3.2, P < 0.001). At 1 month, significantly fewer patients in the fibrin glue group reported pain, numbness, and discomfort compared with patients in the sutures group (all P < 0.05). Fibrin glue patients also experienced less intense pain (0.6 vs. 1.2; P = 0.001). By 3 months, the between-group differences had disappeared, except for numbness, which was more prevalent in the sutures group. By 12 months, very few patients reported complications.

CONCLUSIONS

Tissucol fibrin glue for mesh fixation in the Lichtenstein repair of inguinal hernia shows advantages over sutures, including lower incidence of complications such as pain, numbness, and discomfort, and should be considered as a first-line option for mesh fixation in hernioplasty.

Vapour pressure of a fragrance ingredient during evaporation in a simple emulsion

The phase diagram water, phenethyl alcohol and laureth 4 was determined and the variation of the vapour pressure of the alcohol was determined during evaporation using gas chromatographic head-space analysis. The phase changes during evaporation were estimated from the phase diagram and compared to the appearance of the emulsion using optical microscopy. The transfer of the fragrance ingredient between different phases during the process was estimated and its measured vapour pressures compared to those calculated from values of earlier determination in different phases in the system. The agreement was good.

ePTFE soft tissue patch reconstruction of hemidiaphragmatic agenesis with late clinical presentation

In this paper we describe a case of a 71-year-old man affected by left hemidiaphragm agenesis who presented an extensive enterothorax after an asymptomatic history for many years. The patient had late development of severe constipation and occasional episodes of bowel obstruction and vomiting. The surgical correction of this congenital anomaly consisted of restoring the continuity of the diaphragmatic barrier with a 2-mm-thick expanded polytetrafluoroethylene soft tissue patch(Gore-Tex) after the herniated viscera have been replaced into the abdominal cavity. At 26 months' follow-up no recurrence has been observed. We would suggest that this is the first known elderly patient surgically treated and the eighth case reported in the literature. The use of a single-layer ePTFE mesh allows a good anatomical and functional repair. An overview of the literature is also reported.

Crura ultrastructural alterations in patients with hiatal hernia: a pilot study

BACKGROUND

Laparoscopic fundoplication for gastroesophageal reflux disease (GERD) and hiatal hernia has been validated worldwide in the past decade. However, hiatal hernia recurrence still represents the most frequent long-term complication after primary repair. Different techniques for hiatal closure have been recommended, but the problem remains unsolved. The authors theorized that ultrastructural alterations may be implicated in hiatal hernia. Thus, this study was undertaken to investigate the presence of these alterations in patients with or without hiatal hernia.

METHODS

Samples from Laimer-Bertelli connective membrane and muscular crura at the esophageal hiatus were collected from 19 patients with GERD and hiatal hernia (HH group), and from 7 patients without hiatal hernia enrolled as the control group (NHH group). Specimens were processed and analyzed by transmission electron microscopy.

RESULTS

Muscle and connective samples from the NHH group did not present any ultrastructural alteration that could be detected by transmission electron microscopy. Similarly, connective samples from the HH group showed no ultrastructural alterations. In contrast, all muscle samples from the HH group exhibited sarcolemmal alterations, subsarcolemmal vacuolar degeneration, extended disruption of sarcotubular complexes, increased intermyofibrillar spaces, and sarcomere splitting.

CONCLUSION

The evidence of ultrastructural alterations in all the patients in the HH group raises the suspicion that the long-term outcomes of antireflux surgery depend not only on the surgical technique, but also on the underlying muscular diaphragmatic illness.

Expression of the novel co-stimulatory molecule B7-H4 by renal tubular epithelial cells

Crosstalk between T cells and renal tubular epithelial cells (TECs) in the pathogenesis of tubular lesions, the most important sign of progressive renal diseases, has not been clarified. Previous work has shown that TECs harbor co-stimulatory signals that promote T-cell activation, which induces tubular lesions. Nevertheless, the expression and functional role of B7-H4, a recently identified co-stimulatory ligand of the B7 superfamily, in pathologic human kidneys is unclear. We investigated the expression of B7-H4 on cryostat renal biopsies from patients with idiopathic membranous nephropathy (n=20), immunoglobulin A nephropathy (n=19), lupus nephritis (n=16), and acute renal allograft rejection (n=15) using immunohistochemistry. In addition, we also analyzed TEC-associated B7-H4 in the regulation of T-cell activation. Immunohistological staining revealed that B7-H4 antigen is restricted to tubular epithelium and that the protein is prominent in sections with severe tubular lesions, although no correlation was observed between tubular B7-H4 expression and levels of serum creatinine, serum urea nitrogen concentration, and 24-h proteinuria in each type of nephropathy. In vitro, mixed lymphocyte reactions revealed that TEC-related B7-H4 promotes cytokine (interleukin-2 and interferon-gamma) production and proliferation of co-cultured T cells. Interestingly, the secretion of interleukin-2 by C10 T cell hybridomas also increased when C10 cells were co-cultured with the B7-H4-transgenic murine TEC line, 3M-1-secreting tubular epithelial cells (MCT) in the presence of the antigen hen egg lysozyme. Our results clearly show that TEC-associated B7-H4 induces T-cell activation and we propose that B7-H4 is a potential activator that promotes tubular lesion.

Feasibility of Primary Inguinal Hernia Repair with a New Mesh

BACKGROUND

The purpose of this study was to evaluate the feasibility of primary inguinal repair with open tension-free and sutureless technique using a new polypropylene "patch and plug system" (Prolene 3D patch), and the quality of the treatment in terms of reduction of postoperative discomfort.

METHODS

Fifty-six consecutive patients, mean age 54.5+/-11.2 years, with primary unilateral uncomplicated inguinal hernia, were treated in a day-surgery setting. Collected data included: pain scores at 24 hours, 72 hours, and 7, 15, and 30 days after operation, analgesic medications, return to work and to heavy house and/or moderate sporting activities, and quality of life as measured by Short Form 36 health survey questionnaire (SF-36) before the operation and at 6 months follow-up.

RESULTS

Postoperative pain was low: the mean visual analog scale (VAS) scores were 2.8 at 24 h, 1.8 at 72 h, and 0.9, 0.3, and 0.04 at 7, 15, and 30 days, respectively. Analgesic drugs were not used by 66.0% (n=37) of the patients. The mean global time to return to work and to heavy activities was 9.9+/-4.6 and 14.6+/-7.0, days, respectively. Patient satisfaction showed a significant improvement in all SF-36 domain scores at 6 months follow-up (P<0.001). There were no major complications, recurrences, or mortality.

CONCLUSIONS

The new mesh seems to satisfy all requirements of a feasible, reliable, and effective device for repairing primary inguinal hernia with high patient comfort.

New devices for inguinal hernia repair in elderly patients

A recent meta-analysis concluded that there was a lower incidence of recurrences after mesh hernioplasty, as opposed to non-mesh open methods. Inguinal mesh and plug hernioplasties have been performed using prostheses of different sizes and shapes, either sutured or not to the tissues. However, hernia repair using mesh is sometimes associated with postoperative pain, more or less severe and/or persistent. As a consequence it may interfere with the time required to return to work and to normal daily activities. Finally, concerning the postoperative complications and recurrences, the data presented in our study confirm the very low rate for both aspects; then, as regards the time to return to work, our good results are similar to those of other studies available in literature. In conclusion the tension-free hernia repair described, based upon the use of Prolene 3D patch, is a safe operation, simple to be acquired, it can be performed on an outpatient basis, with a low complication rate, a low level of pain, and an excellent quality of life thereafter. The new device seems to satisfy all requisites of a feasible, reliable and effective system for repairing primary inguinal hernia, at low cost, high patient comfort, and with low risk of recurrences.

Psycho-biological correlates of hypoactive sexual desire in patients with erectile dysfunction

We studied the psychological and biological correlates of hypoactive sexual desire (HSD) in a consecutive series of 428 patients with erectile dysfunction (ED), by using the structured interview SIEDY. A complete physical examination and a series of biochemical, hormonal, psychometric, and penile vascular tests were also performed. Among the patients studied, 22.8% reported a mild, 12.9% a moderate, and 4.6% a complete loss of sexual interest. Patients reporting HSD showed significantly lower testosterone (T) levels than the rest of the sample, although the prevalence of hypogonadism (T<10 nM) was comparable in the two groups. Only a minority (<2%) had severe hyperprolactinemia (>700 mU/l), which, nonetheless, was closely associated with a relevant HSD. Both mental disorders and use of medication interfering with sexual function were significantly associated with HSD, as well as depressive and anxiety symptoms. HSD patients showed significantly higher scores in SIEDY scale 2, which explores the relational component of ED. In particular, perceived partner's libido and climax were crucially associated with an impairment of patients' sexual desire. In conclusion, HSD in ED is associated with several biological, psychological, and relational factors that can be simultaneously identified and quantified using the SIEDY structured interview.

Advances in cardiac electrophysiology and pacing

Significant advances have been made in the management of cardiac arrhythmias. New technology has enhanced the ability to understand and treat a variety of tachycardias. Excitement and caution surround ablative approaches for atrial fibrillation. The role of ICDs and class III antiarrhythmic drugs in the management of patients at risk for sudden cardiac death has been clarified. A new indication for cardiac pacing is evolving as a supplemental treatment for patients with refractory congestive heart failure. These and other advances provide numerous exciting options for management of cardiac patients.

Clinical analysis on 149 old patients with craniocerebral injury

OBJECTIVE

To study the clinical features of craniocerebral injury (CI) in the aged.

METHODS

The data of 149 old patients with CI hospitalized in t he department from July 1991 to May 2000 were studied retrospectively in this study. The causes of injury, traumatic pathology, clinical manifestation and cause s of death were analyzed, too.

RESULTS

Automobiles were the main victim-makers, and falls we re the second. And there was no significant difference between the first two kin ds of victim-makers. The patients suffered mainly from cerebral contusion, intracerebral hematomas and subdural hematomas, and relatively fewer from epidural hematomas. The scores of Glasgow Coma Scale (GCS) were related closely to the prognosis when hospitalized or before surgical treatment. The total mortality rate was 37.5% in this study. The main cause of death was brain injury.

CONCLUSIONS

The old patients with CI have a high mortality rat e. And the causes of injury, traumatic pathology and clinical manifestation are peculiar in the aged.

Ambulatory oesophageal pH-metry. Position paper of the Working Team on Oesophageal pH-metry by the GISMAD (Gruppo Italiano di Studio sulla Motilità dell'Apparato Digerente)

In the last three decades, oesophageal pH monitoring has progressed from a physiological research tool to a routine outpatient clinical investigation in patients with suspected gastro-oesophageal reflux disease, one of the most common gastrointestinal disorders. Technological progress has considerably simplified both the procedure and the interpretation of data obtained, and there is currently reasonable consensus as to the parameters that best discriminate between physiological and pathological reflux. There remains a need for internationally agreed definitions and standards with regard to indexes to quantitate the extent and the significance of the relationship between occurrence of symptoms and reflux episodes during the examination. It is felt that national or local normal values are to be used to circumvent different eating habits and other socio-cultural differences which may influence gastro-oesophageal reflux. The reproducibility of the test appears, at present, to be at least good enough to allow classification of the patient as a pathological or physiological refluxer, albeit wide day-to-day variations seem to exist as far as concerns the extent of gastro-oesophageal reflux. Clinical applications of the technique have increased with better knowledge of the protean clinical manifestations of gastro-oesophageal reflux disease, and include the evaluation of "typical" gastro-oesophageal reflux disease patients with negative endoscopy or refractory oesophagitis, the "atypical" manifestations of gastro-oesophageal reflux disease and the pre- and post-operative evaluation of patients undergoing antireflux surgery.

Effects of multisite ventricular pacing on cardiac function in normal dogs and dogs with heart failure

INTRODUCTION

We studied the effects on cardiac function of pacing two right and two left ventricular sites in normal and failing hearts with a normal QRS duration.

METHODS AND RESULTS

Hemodynamic parameters were studied in isoflurane-anesthetized dogs with normal hearts and dogs with heart failure induced by rapid ventricular pacing. Unipolar intramyocardial electrodes were placed at the high right atrium and the apex (A) and base (B) of the left (L) and right (R) ventricles (V). Data were collected after pacing for 5 to 20 minutes. In normal dogs, without bundle branch block (BBB), pacing at either the apex or the base of the left ventricle increased cardiac output by approximately 10% compared with right ventricular apex (RVA) pacing with an AV delay of 0 msec. Positive dP/dt increased approximately 10% during four-site left and right ventricular apex and base (LRVAB) pacing compared with RVA pacing. In dogs with heart failure but without BBB, cardiac output increased by 8.5% (P < 0.01) during four-site ventricular pacing with AV delays of 0 and 60 msec compared with RVA pacing. Positive dp/dt increased by 23.5% (P < 0.001) with an AV delay of 0 msec and 9.6% (P < 0.001) with an AV delay of 60 msec during LRVAB pacing compared with RVA pacing. His-bundle pacing was associated with increased cardiac output compared with RVA pacing.

CONCLUSIONS

We conclude that pacing simultaneously at two right and two left ventricular sites significantly improves cardiac function compared with single RVA pacing, with or without sequential AV synchrony, in dogs with rapid ventricular pacing-induced heart failure and no BBB.

Well differentiated "lipoma-like" liposarcoma of the sigmoid mesocolon and multiple lipomatosis of the rectosigmoid colon. Report of a case

Liposarcoma is the second most common soft tissue sarcoma in adults. These neoplasms take their origin from primitive mesenchymal cells and are rarely encountered in fat rich areas, such as subcutaneous tissue and/or the subserosa of the intestinal tract which, on the contrary, are the two most common sites of lipomas. The two major locations of liposarcomas are the extremities and the retroperitoneum followed with much less frequency by the inguinal region. Other sites are uncommon, particularly the mesentery (9 cases to date in the literature) and, even more so, the mesocolon (only 3 cases of primary sarcoma of the mesocolon reported to date). This paper reports on the case of a well differentiated "lipoma-like" liposarcoma of the sigmoid mesocolon, associated with multiple lipomatosis of the recto-sigmoid colon in a 75 year-old female patient. Surgical treatment consisted of a trans-anal extra-peritoneal anterior resection by CEEA 28 stapler under endoscopic vision. The patient has been followed up for the last 2 years and is still disease-free and well. The peculiarity of the case consists in the contemporaneous presence in close contiguity of two different rare neoplasms whose association is not yet known.

Intrapericardial delivery of L-arginine reduces the increased severity of ventricular arrhythmias during sympathetic stimulation in dogs with acute coronary occlusion: nitric oxide modulates sympathetic effects on ventricular electrophysiological properties

BACKGROUND

Nitric oxide (NO) modulates autonomic effects on myocardial contractility and sinus and atrioventricular nodal function of the heart. Whether NO influences autonomic actions on ventricular electrophysiological properties and arrhythmogenesis is not known.

METHODS AND RESULTS

Four groups consisting of 43 autonomically denervated dogs were studied. To "superfuse" sympathetic nerves innervating the ventricles, test drugs were introduced into the pericardial sac for 30 minutes, and their effects on ventricular effective refractory period (ERP) and arrhythmia development were assessed before and during sympathetic stimulation (SS). In group 1 (n=12), ventricular ERPs showed no significant difference between control and superfusion with L-arginine, a NO precursor (222+/-20 versus 222+/-19 ms, P=.485). However, L-arginine significantly reduced SS-induced ERP shortening compared with control (9+/-7 versus 13+/-7 ms, P<.001). Simultaneous administration of N(G)-monomethyl-L-arginine (2 mg/mL) abolished the inhibitory effects of L-arginine (13+/-7 versus 13+/-7 ms, P=.885). In group 2 (n=15), the severity of ventricular arrhythmias significantly increased during SS. L-Arginine reduced this increase caused by SS. In group 3 (n=8), plasma norepinephrine spillover measured from the coronary sinus significantly increased during SS and was reduced by pericardial superfusion with L-arginine compared with control (6005.2+/-1525.6 versus 8503.4+/-2044.5 pg/min, P=.012). In group 4 (n=8), L-arginine pericardial superfusion significantly increased NO overflow measured from the coronary sinus during SS (93.25+/-59.20 versus 114.82+/-74.92 nmol/min, P=.043).

CONCLUSIONS

Pericardial L-arginine reduces ERP shortening and increased severity of ischemic ventricular arrhythmias during SS in dogs. NO-induced reduction of norepinephrine release in the heart may be one of the underlying mechanisms.

Analysis of thymoma excision in patients with myasthenia gravis

OBJECTIVE

To study the clinical characteristics of myasthenia gravis (MG) with thymoma and the effect of tracheostomy at the early stage after operation.

METHODS

Thymoma excision and selective tracheostomy were performed on 46 patients with MG from March 1983 to December 1994.

RESULTS

There were 15 patients with benign thymomas and 31 patients with malignant thymomas. MG crises were seen in 52.2% of patients postoperatively, most in type IIb and III. The mortality of in-patients after operation was 10.9%. Thirty-nine patients with thymoma were followed up for 6 months to 12 years after being discharged from hospital. The MG symptoms were relieved in 33.3%, improved in 20.5% and unchanged in 2.6% of patients. 38.5% of patients died of the disease.

CONCLUSION

The characteristics of MG with thymoma are, more severe condition of the patient, rapid advance, and more MG crises before and after operation. The perioperative mortality from MG with thymoma is higher and its prognosis is unfavourable. It is very important to treat severe cases of MG with thymoma by tracheostomy with thymoma excision at the early stage after the operation. This is an effective method to prevent and treat MG crises as well as to lower the perioperative mortality.

[Anti-tumor activity and immune responses induced by human cancer-associated mucin core peptide]

Mucin molecules are displayed on most human cancer cell surface, and are different from that expressed on normal epithelial cells. The molecular structure of mucin core peptide (apomucin) was identified recently. However, the function of apomucin is only poorly understood. To further elucidate the role of apomucin in the modulation of cancers, this study was to investigate the immune responses induced by mucin core peptide in mice. The mucin core peptide was isolated from pancreatic cancer cell line SW1990. When mice immunized with this apomucin (10 micrograms/time x 6) plus DETOX, all mice developed delayed-type hypersensitivity (DTH) after challanged with apomucin or synthetic mucin core peptide MUC-2 or MUC-3, while the mice immunized with only apomucin did not develop DTH. No antibodies were detected by ELISA after immunization. When the splenic cells of vaccinated mice were cocultured with this apomucin (10-50 micrograms/ml) and rhIL-2 (50 U/ml) in vitro, the proliferated lymphocytes showed cytotoxicity against human cancer cells, including colon cancer, gastric cancer, pancreatic cancer and leukemia as measured by Cr-51 release assay. The cytotoxicity could be blocked by antibodies against MUC-2 and MUC-3. These results provide a rational basis for the use of apomucin as a vaccine to stimulate anti-tumor immunity.

Effects of hypothyroidism on the vulnerability to ventricular fibrillation in dogs: a comparative study with amiodarone

It has been shown that thyroid hormone has a significant effect on the heart and that suppression of thyroid function may contribute to the antiarrhythmic effect of amiodarone. The study was aimed at investigating the effects of hypothyroidism, compared with those of amiodarone, on vulnerability to ventricular fibrillation in dogs. In this study, 25 adult dogs were randomly divided into three groups: a hypothyroid group following total thyroidectomy (n = 9), an amiodarone group (n = 8, 400 mg per day, 4 weeks), and a control group (n = 8). Both amiodarone and control groups were subjected to sham surgery. Five to 8 weeks after surgery, ventricular fibrillation threshold and other electrophysiological parameters were determined. Right ventricular effective refractory period, monophasic action potential duration, and ventricular fibrillation threshold were significantly increased in both the thyroidectomized and amiodarone-treated animals. There was no significant change in monophasic action potential duration dispersion. The incidence of ventricular fibrillation during ischemia and reperfusion was significantly reduced in both treated groups compared with the sham-operated euthyroid controls. These observations suggest that hypothyroidism has a significant antifibrillatory effect in dogs. Homogeneous prolongation of repolarization and refractoriness may contribute to the antifibrillatory action of hypothyroidism.

Chronotropic incompetence--Part II: Clinical implications

The definition of chronotropic incompetence as inadequate chronotropic response to metabolic demand is, in theory, quite satisfactory. However, the method used in clinical practice for determination of chronotropic incompetence is far from established. The determination of chronotropic incompetence has important diagnostic, therapeutic, and prognostic implications although the exact mechanism underlying chronotropic incompetence is at present unclear. From a pacing viewpoint, chronotropic incompetence is clinically relevant only when there is a functional improvement associated with rate-responsive pacing. Rate-responsive pacing has improved the physiologic approach to artificial pacing.

[Influence of the duration of recording in the reproducibility of the signal averaged electrocardiogram]

The authors studied the possibility of improving the reproducibility of the signal averaged ECG by increasing the number of averaged QRS complexes. One hundred patients were included in the study. In each cases, 400 QRS complexes were recorded on twice, consecutively, in strictly identical conditions. During each recording, the total duration of the amplified and averaged QRS complex (tQRS), the duration of the terminal signal below 40 microV (LAS) and the root mean square of the amplitude of the last 40 ms (RMS) were determined for 100, 200, 300 and 400 recorded QRS complexes. The presence of late potentials was defined as the positivity of two of the following criteria: tQRS > 114 ms, LAS > 38 ms, RMS < 20 microV. The number of contradictory diagnostic conclusions between two successive recordings of the same duration decreased progressively with the number of averaged QRS complexes: 10 for 100 QRS, 10 for 200 QRS, 9 for 300 QRS and 6 for 400 QRS complexes, but this improvement was not statistically significant. The absolute differences of tQRS and RMS between two successive recordings of the same duration were statistically different for the four durations of recording (p = 0.05) and there was a tendency towards statistical significance for LAS (p = 0.09). The best quantitative reproducibility of the 3 parameters was obtained with the recording of 300 QRS complexes. In conclusion, the reproducibility of the signal averaged ECG is improved when the number of average QRS complexes is increased. The authors' results suggests that reproducibility this is optimal with the amplification and averaging of 300 QRS complexes.

Chronotropic incompetence--Part I: Normal regulation of the heart rate

Knowledge of normal adjustment of heart rate and its response to exercise is essential for understanding and management of chronotropic incompetence. The autonomic nervous system plays an important role in the modulation of normal heart rate. Chronotropic responses of a normal heart to exercise are associated with parallel hemodynamic changes in order to meet the metabolic demand of the body. Determination of chronotropic incompetence is widely based on the assessment of maximal heart rate. However, maximal effort should always be confirmed before an attempt to measure a maximal heart rate is made.

Short- and long-term assessment of heart rate variability for risk stratification after acute myocardial infarction

Depressed heart rate variability (HRV) has been shown to be a powerful and independent risk factor in patients following acute myocardial infarction (AMI). A detailed comparison of the predictive values between short- and long-term HRV has not been made. The predictive value of short-term HRV for 1-year total cardiac mortality was studied in 700 consecutive patients after AMI. All patients underwent 24-hour Holter monitoring before discharge from the hospital (5 to 8 days after AMI) and were followed up for 1 year. Short-term HRV was computed as the standard deviation of all normal RR intervals (SDNN) from a 5-minute stationary period selected from 24-hour Holter electrocardiographic recordings. Long-term HRV was computed as an HRV index over the entire 24 hours. There was a significant but relatively poor correlation between SDNN and HRV index (r = 0.51, p <0.001). The positive predictive accuracy of SDNN for 1-year mortality (13% to 18%) was lower than the HRV index (17% to 43%) over a range of sensitivity of 25% to 75%. Assessment of HRV index in > or = 35% of the patients preselected by the lowest SDNN was able to achieve predictive power similar to that of HRV index assessed in all the patients. These data suggest that lower predischarge short-term HRV is associated with increased 1-year total cardiac mortality in patients after AMI. Analysis of long-term HRV for postinfarction risk stratification can safely be limited to patients preselected by depressed short-term HRV measures.

Decreased heart rate variability in patients with congestive heart failure and chronotropic incompetence

Heart rate variability was studied in 41 patients (aged 48 +/- 12 years) with congestive heart failure secondary to idiopathic dilated cardiomyopathy. All patients underwent a treadmill exercise test and 24-hour Holter ECG monitoring. Chronotropic incompetence was defined as the failure to achieve > or = 80% of the predicted maximal heart rate response given by 220--age (years) at peak exercise. Spectral heart rate variability was analyzed from 24-hour Holter ECGs and was expressed as total (0.01-1.00 Hz), low (0.04-0.15 Hz), and high (0.15-0.40 Hz) frequency components. The standard deviation of all normal RR intervals (SDNN) was also computed. Chronotropic incompetence was observed in ten patients. Peak oxygen consumption was significantly lower in patients with chronotropic incompetence compared with those without chronotropic incompetence. The total (5.11 +/- 1.26 ln [ms2] vs 6.41 +/- 0.92 ln [ms2]; P = 0.009) and low (3.38 +/- 1.65 ln [ms2] vs 5.45 +/- 1.34 ln [ms2]; P = 0.003), but not the high (3.42 +/- 1.04 ln [ms2] vs 4.00 +/- 1.12 ln [ms2]; P = 0.249) frequency components of heart rate variability were significantly lower in patients with chronotropic incompetence, although there was no significant difference in mean heart rate (88 +/- 20 beats/min vs 86 +/- 15 beats/min; P = 0.831) or left ventricular ejection fraction (22% +/- 10% vs 24% +/- 10%; P = 0.619). SDNN was also significantly lower in patients with chronotropic incompetence compared with those without chronotropic incompetence (64 +/- 34 ms vs 102 +/- 37 ms; P = 0.030).

CONCLUSIONS

The observation that heart rate variability is significantly decreased in patients with congestive heart failure who have chronotropic incompetence suggests that chronotropic incompetence may relate to an abnormal autonomic influence on the heart in these patients.

[Reproducibility of signal-averaged electrocardiography]

The reproducibility of the parameters defining the presence of late potentials on the signal-averaged electrocardiogram is one of the limiting factors of the method. The authors studied the coefficients of correlation and reproducibility of these parameters in patients with coronary artery disease. In addition, they tried to determine which parameter was most often responsible for changing a diagnostic conclusion (i.e., presence or absence of late potentials). Two signal-averaged ECGs were recorded one after the other in 127 patients. The presence of late potentials was defined as the presence of a least two of the following criteria: total amplified and averaged QRS duration (tQRS) > 114 ms: duration of the last signal of under 40 microV (LAS) > 38 ms, and root mean square of the amplitude of the last 40 ms (RMS) < 20 microV. The correlation coefficients were 0.98, 0.96 and 0.94 for the duration of tQRS, LAS and RMS respectively (p < 0.0001). The coefficients of reproducibility were 7.0 ms. 7.0 ms and 16.1 microV respectively. Late potentials were present in 22% of patients. A change in diagnosis between the first and second recording was observed in 10 subjects (8% of the population). A combined change in LAS and RMS was responsible for 6 of these revised diagnoses, a change in LAS alone in 2 cases, of the RMS alone in 1 case and the tQRS alone in 1 case. In patients with coronary artery disease, the immediate reproducibility of the diagnosis of late potentials is affected by changes in LAS and RMS. The tQRS is only rarely responsible for a change in diagnosis. This study suggests that the result of the signal-averaged ECG should be interpreted with caution when the LAS or RMS are near their threshold values.

Predictive power of increased heart rate versus depressed left ventricular ejection fraction and heart rate variability for risk stratification after myocardial infarction. Results of a two-year follow-up study

OBJECTIVES

The aim of this study was to compare the predictive value of mean RR interval assessed from predischarge Holter recordings with that of heart rate variability and left ventricular ejection fraction for risk stratification after myocardial infarction.

BACKGROUND

Heart rate variability is a powerful tool for risk stratification after myocardial infarction. Although heart rate variability is related to heart rate, little is known of the prognostic value of 24-h mean heart rate.

METHODS

A total of 579 patients surviving the acute phase of myocardial infarction were followed up for at least 2 years. Predischarge heart rate variability, 24-h mean RR interval and left ventricular ejection fraction were analyzed.

RESULTS

During the first 2 years of follow-up, there were 54 deaths, 42 of which were cardiac (26 sudden). Shorter mean RR interval was a better predictor of all-cause mortality as well as cardiac and sudden death than depressed left ventricular ejection fraction. Depressed heart rate variability predicted the risk of death better than mean RR interval for sensitivities < 40%. For sensitivities > or = 40%, mean RR interval was as powerful as heart rate variability. All three variables performed equally well in predicting nonsudden cardiac death. For cardiac death prediction, a left ventricular ejection fraction < 35% had a 40% sensitivity, 78% specificity and 14% positive predictive accuracy; a mean RR interval < 700 ms had a 45% sensitivity, 85% specificity and 20% positive predictive accuracy; and a heart rate variability < 17 U had a 40% sensitivity, 86% specificity and 20% positive predictive accuracy.

CONCLUSIONS

Predischarge 24-h mean heart rate is a strong predictor of mortality after myocardial infarction that can compete with left ventricular ejection fraction and heart rate variability.

QT dispersion and RR variations on 12-lead ECGs in patients with congestive heart failure secondary to idiopathic dilated cardiomyopathy

Increased QT dispersion, which has been proposed as a marker of ventricular repolarization inhomogeneity, may predispose to ventricular arrhythmias. Data on QT dispersion in patients with congestive heart failure are scarce. In this study, conventional 12-lead ECGs were recorded in 135 consecutive patients with congestive heart failure secondary to idiopathic dilated cardiomyopathy. Seventy-five patients were excluded from QT interval assessments due to one or more of the following reasons: (1) low amplitude of the T wave (n = 3), (2) atrial fibrillation (n = 26) and (3) bundle branch block (n = 46). QT dispersion was calculated as (1) QT-range: the difference between the maximum and minimum QT intervals on any of the 12 leads and (2) QT-SD: the standard deviation of the QT interval in all the 12 leads. RR intervals were measured in leads II, aVL, V2 and V5. QT-SD (20.85 +/- 5.00 ms) was significantly (r = 0.8997, P < 0.001) related to QT-range (65.65 +/- 15.77 ms), but not to the QT interval. Neither QT-range nor QT-SD was significantly related to age, left ventricular dimensions, left ventricular end diastolic pressure, left ventricular ejection fraction or left ventricular wall thickness. There was no significant difference in QT dispersion between survivors and those who died (n = 8) or were transplanted (n = 9) during 34 +/- 23 month follow-up. No significant difference in QT dispersion was observed between patients with and without ventricular tachycardia (> or = three consecutive beats) detected on 24-h Holter ECGs. RR interval variation was significantly lower in patients who died compared with survivors (standard deviation: 10.37 +/- 3.61 vs 36.02 +/- 35.03 ms, P < 0.001; coefficient of variance: 1.87 +/- 0.7% vs 4.50 +/- 4.9%, P = 0.001). This was also true in patients with bundle branch block. These observations suggest that QT dispersion in idiopathic dilated cardiomyopathy is not significantly related to either QT interval or cardiac size and function and does not predict death. The application of QT dispersion assessment is limited by the commonly encountered atrial fibrillation and bundle branch block in this patient population. However, reduced RR variation on standard 12-lead ECGs has important prognostic implications in these patients.

Phase II study of high-dose epirubicin, lonidamine, alpha 2b interferon in advanced breast cancer

44 patients with advanced breast cancer were treated with high-dose epirubicin (130 mg/sqm), because of its steep dose-response curve. Lonidamine and alpha interferon were administered as well with the aim of increasing epirubicin uptake and overcoming drug resistance. Granulocyte-colony stimulating factor support was provided. 14 complete responses and 22 partial responses were observed in 40 evaluable patients for a 90% overall response rate. Median duration of response was 12 months for complete responders, 7 months for partial responders. In two cases the complete response has lasted for more than two years. Myelosuppression, infection, and cardiac toxicity were the main treatment-related toxic effects. These results are encouraging enough to justify a randomized comparison of our chemotherapy program with standard regimens used in advanced breast cancer.

Is there increased sympathetic activity in patients with hypertrophic cardiomyopathy?

OBJECTIVES

This study aimed to assess autonomic nervous system activity in patients with hypertrophic cardiomyopathy.

BACKGROUND

Patients with hypertrophic cardiomyopathy are traditionally thought to have increased sympathetic activity. However, convincing evidence is lacking.

METHODS

Heart rate variability was assessed from 24-h ambulatory electrocardiographic (Holter) recordings in 31 patients with hypertrophic cardiomyopathy and 31 age- and gender-matched normal control subjects in a drug-free state. Spectral heart rate variability was calculated as total (0.01 to 1.00 Hz), low (0.04 to 0.15 Hz) and high (0.15 to 0.40 Hz) frequency components using fast Fourier transformation analysis.

RESULTS

There was a nonsignificant decrease in the total frequency component of heart rate variability in patients with hypertrophic cardiomyopathy compared with that of normal subjects (mean +/- SD 7.24 +/- 0.88 versus 7.59 +/- 0.57 ln[ms2], p = 0.072). Although there was no significant difference in the high frequency component (5.31 +/- 1.14 versus 5.40 +/- 0.91 ln[ms2], p = 0.730), the low frequency component was significantly lower in patients than in normal subjects (6.25 +/- 1.00 versus 6.72 +/- 0.61 ln[ms2], p = 0.026). After normalization (i.e., division by the total frequency component values), the low frequency component was significantly decreased (38 +/- 8% versus 43 +/- 8%, p = 0.018) and the high frequency component significantly increased (16 +/- 6% versus 12 +/- 6%, p = 0.030) in patients with hypertrophic cardiomyopathy. The low/high frequency component ratio was significantly lower in these patients (0.94 +/- 0.64 versus 1.33 +/- 0.55, p = 0.013). In patients with hypertrophic cardiomyopathy, heart rate variability was significantly related to left ventricular end-systolic dimension and left atrial dimension but not to maximal left ventricular wall thickness. No significant difference in heart rate variability was found between 14 victims of sudden cardiac death and 10 age- and gender-matched low risk patients.

CONCLUSIONS

Our observations suggest that during normal daily activities, patients with hypertrophic cardiomyopathy experience a significant autonomic alteration with decreased sympathetic tone.