Risk of jugular compression blocks in workers exposed to prolonged upright posture.

BACKGROUND: The working posture affects the peripheral venous circulation, although the current literature does not report any correlation between working posture and the abnormalities of the jugular veins flow. The purpose of this preliminary research is to study, in female workers, the prevalence of Venous Compressive Syndrome (VCS) caused by total block of the internal jugular veins flow, so-called "White Compression". Due to complete compression by postural, muscular, fascial, anatomical or bone anomalies, White Compression is not visible by EchoColorDoppler (ECD) and its flow can only be detected by the rotational movements of the head or by Valsalva's maneuver. METHODS: We studied a sample of female workers with ECD (n=128), in supine and upright position divided into subgroups according to the obliged posture maintained during working hours: group A, seated work (n = 61; 47.7%); group B, standing work (n = 41; 32.0%); group C, mixed (both standing and seated work) (n = 26; 20.3%). The total sample (n = 128) had the mean age of 46 ± 10 years (minimum 18 and maximum 67 years) and mean Body Mass Index (BMI) of 23 ± 4 kg/m2 (min 16 kg/m2 and a maximum of 42 kg/m2). RESULTS: Group A and group C did not show any White Compression in orthostatic and clinostatic position. The 9.75% (p = 0.0125) of Group B had a White Compression in orthostatic position: two female workers on the left side (4.9%) and two female workers on the right side (4.9%). CONCLUSIONS: We conclude that there is a risk of jugular compression blocks in female workers exposed to prolonged upright posture. Yet there is no longitudinal study that identifies the White Compressions as etiology of a chronic neurodegenerative disease. The authors hope that some wider studies can confirm the prevalence of these compressions in standing posture and their patho-physiological consequences.

Italy and Argentina compared: an epidemiological study of occupational diseases.

BACKGROUND: The research presented in this paper analyses the clinic-pathological manifestations and work-related health risks identified among outpatients treated in the hospitals of Rome and Buenos Aires. MATERIALS AND METHODS: The occupational anamnestic data were collected between 2013 and 2014 through questionnaires with specific items aimed at detecting occupational diseases classified by target organ systems in outpatient clinics of cardiology, dermatology, physical medicine, ophthalmology, orthopedics, endocrinology (thyroid and gonads). An inferential statistical analysis was then carried out to evaluate the relationship between nationality, exposure to occupational risks and the prevalence and incidence of the selected pathologies. An univariate statistical analysis was performed for this purpose and, in the case of statistically significant results, a subsequent multivariate analysis was used to evaluate the incidence of occupational risk factors and nationality on the pathology diagnosed in conjunction with other confounding factors such as smoking habits and gender. The total sample consisted of 1090 subjects of both sexes. Risks were grouped into seven categories and diseases into 12 diagnostic groups. We analyzed the correlation between risks and diseases with respect to hospital outpatients and to the total sample then comparing Argentina and Italy's data. RESULTS: Analysis of data revealed a higher prevalence of hypertension and dysmetabolic disorders for DSE (Display Screen Equipment) workers both in Italy and Argentina; however, multivariate analysis showed that smoking represents a confounding factor for this association. A higher prevalence of allergic contact dermatitis (ACD) was found in the population samples of Rome and there appeared to be a correlation between eye disorders/defects and Argentine data source. CONCLUSIONS: Our study suggests the usefulness of collecting occupational anamnestic data from outpatient departments to highlight possible associations between occupational risks, lifestyles and pathologies, so as to implement the appropriate prevention strategies.

Atrial fibrillation in the acute, hypercapnic exacerbations of COPD.

OBJECTIVE: Chronic obstructive pulmonary disease (COPD) has been associated with a high frequency of arrhythmias. Atrial fibrillation (AF) is one of the most common arrhythmias and causes substantial morbidity and mortality. Emerging risk factors for the development of AF include a variety of breathing disorders like COPD. Few studies have analyzed the role of reduced lung function and respiratory acidosis in predicting AF. Aim of the current study was to investigate the role of hypercapnia, pulmonary systolic hypertension and lung function impairment in COPD patients, as risk factors for atrial fibrillation development. PATIENTS ANDV METHODS: We evaluated a population of individuals consecutively hospitalized for COPD exacerbation and hypercapnic respiratory failure between January 2012 and January 2013; among them we selected a subgroup of patients presenting a paroxysmal episode of atrial fibrillation. All patients underwent pulmonary function tests, haemogasanalysis, electrocardiogram and transthoracic echocardiography. RESULTS: Among the 193 subjects evaluated, 35 individuals with AF and COPD were enrolled in the study. Risk of new AF was higher in those subjects with lower FEV1 and higher PaCO2 values, also there was a significantly increased prevalence of AF in patients with higher value of Pulmonary Artery Systolic Pressure (PASP), obtained by transthoracic echocardiography. Linear correlation between variables revealed a direct relationships between hypercapnia and PASP and left and right atrial areas. CONCLUSIONS: Impaired pulmonary function, hypercapnia and high values of PASP are independent predictors of incident AF.

Resistive index and MELD-Na: nephrologic monitoring in cirrhotic patients awaiting liver transplantation.

Renal dysfunction in cirrhotic patients is primarily related to disturbances in circulatory function. In decompensated cirrhosis, ascites and water retention are associated with development of dilutional hyponatremia. The arterial resistive index (RI) is a measure of resistance to arterial flow within the renal vascular bed. Hyponatremia is an independent predictor of mortality in patients with ascites. The aim of this study was to evaluate intrarenal RI in end-stage liver disease (ESLD) patients awaiting liver transplantation (LT) and its association with renal and hepatic function as assessed by Model for End-Stage Liver Disease (MELD) and MELD-Na scores. We evaluated 40 cirrhotic patients (23 males, 17 females) awaiting LT from January 2009 to January 2012. Twenty-six of the 40 patients (65%) showed a renal RI ≥ 0.70, the normal value according to standard reported evaluations. Patients with RI ≥ 0.70 showed significantly higher MELD and MELD-Na scores as well as greater higher serum creatinine and lower serum sodium concentrations compared with subject displaying RI <0.70. The most relevant result of our study was the strong association between elevated renal RI in ESLD patients and advanced liver dysfunction, as demonstrated by MELD and MELD-Na scores, hyponatremia, ascites, and acute renal failure episodes. In conclusion, this study suggested that intrarenal RI assessment should be considered in the clinical and nephrologic monitoring of cirrhotic patients awaiting LT.

[Cardiovascular diseases in workers at risk]. / Cardiovasculopatie in lavoratori a rischio.

Our research group has conducted several studies to investigate the effects of occupational risks on the cardiovascular system of exposed workers. In these studies, groups of workers exposed to possible professional cardiovascular risk factors were compared with controls with respect to some parameters (blood pressure, ECG, etc.). The groups were made comparable by age, length of service, traditional cardiovascular risk factors and possible confounding factors outside work. Four studies investigated the effects of noise exposure, three studies the effects of exposure to urban stressors, other studies the presence of other cardiovascular risk factors in various occupational categories (manual workers, agricultural workers, workers exposed to ionizing radiation, workers in rotogravure factory). The results of our studies confirm the presence of cardiovascular risk factors in various professions and the consequent need to take develop preventive strategies in workplaces to prevent the onset of cardiovascular diseases associated with these risk factors.

[Phlebopathies and workers]. / Flebopatie e lavoratori.

The few studies in literature about the relationship between venous diseases and work show that the posture assumed while working could promote the occurrence of venous disease in lower limbs. We compared male workers belonging to different occupational categories, matched for age, BMI and traditional risk factors for venous diseases, in order to assess the prevalence of venous disease and occupational and not-occupational postural risk factors. We found that maintaining a standing position for more than 50% of the shift appears the most important occupational risk factor in provoking the observed higher prevalence of venous disease in the workers studied. It can be assumed the venous diseases are often determined by occupational factors which could be main or concomitant causes. The identification of preventive measures to apply in workplaces, such as better organization of work, targeted examinations and therapeutic indications as the prescription of elastic stockings, is very important.

[Meta-analysis: cardiovascular effects in workers occupationally exposed to urban pollution]. / Metanalisi: effetti sull'apparato cardiovascolare in lavoratori esposti a inquinamento urbano.

BACKGROUND: Many studies showed a connection between exposition to high levels of urban pollution (especially to particulate and traffic noise) and the onset of even deadly cardiovascular diseases. DESIGN: Meta-analysis of case-control design. OBJECTIVES: The aim of this study is to estimate the association between cardiovascular effects and occupational exposition to atmospheric pollution in urban environment. DATA SOURCES: Biomedcentral, MEDLINE/ PubMed, MEDLINE/ National Library of Medicine (NLM), MEDLINE Plus, Nioshtic-2, Scopus, TOXNET/Toxline, unpublished studies known by the authors and acts of national and international conferences between 1988 and May 2010 included. There has not been any kind of language or typological restriction. CRITERIA OF ELEGIBILITY: The research on cardiovascular effects includes control cases of workers exposed to urban pollution, compared with non-exposed subjects. PARTICIPANTS AND INTERVENTIONS: The selected studies present outdoor workers exposed to urban pollution (drivers and petrol pump attendants) and a control group of indoor workers (managers, university students and other selected subjects). STUDY APPRAISAL AND SYNTHESIS METHODS: The evidences (independently token from two different authors) have been grouped in two classes, the first one formed by continuous variables (systolic blood pressure, diastolic blood pressure, heart rate, total cholesterol, HDL cholesterol, LDL cholesterol, triglycerides) and the second one by discontinuous variables (electrocardiographic abnormalities prevalence, hypertension prevalence, hypercholesterolemia prevalence). The studies related to both classes and presenting more than one variable for each class have been included and used, in order to elaborate the results. We calculated heterogeneity in each variable (ES calculation for continuous variables and OR calculation for discontinuous variables). RESULTS: On 378 publications, we have selected and included 16 articles. The variables show statistically irrelevant differences between exposed group and control group, except regarding the triglycerides. LIMITATIONS: The controlled studies are limited and characterized by a non-homogeneous evaluation of both expositional times of workers to urban pollution and of professional expositional values. CONCLUSIONS AND IMPLICATIONS OF KEY FINDINGS: Considering the heterogeneity and the lack of studies, it is impossible at the moment to document effects on the cardiovascular system in workers exposed to urban pollution. The results of this meta-analysis only suggest the association of urban pollution with alteration of triglycerides blood levels (referring to just three studies). As reported in scientific literature on this subject, it is necessary to conduct a future professional investigation on this subject with more qualified and homogeneous studies.

Influence of human menopausal gonadotrophin treatment on testicular blood flow and on seminal plasma nitric oxide levels in infertile males.

Gonadotrophin treatment is capable of increasing intratesticular blood flow and improving sperm fertilization potential. A nitric oxide (NO)-mediated mechanism may play a role. This study aimed at evaluating whether the increase in intratesticular blood flow, in response to human menopausal gonadotrophin (hMG) treatment, is accompanied by an increase in seminal plasma NO levels in 20 normogonadotropic males affected by severe oligoasthenoteratozoospermia. Patients received 150 IU of hMG, three times a week for 3 months. Before starting treatment and at month 3 of therapy, levels of NO in the seminal plasma were determined, followed by ultrasound scanning of testis, Doppler evaluation of intratesticular vascular resistance, serum hormone and conventional semen evaluation. Statistical analysis was performed by using Wilcoxon test; the limit of statistical significance was p<0.05. At the end of treatment, seminal plasma concentration of NO, conventional semen parameters and testicular volume did not increase significantly. Follicle-stimulating hormone serum level significantly increased (p=0.014) after treatment, whereas luteinizing hormone, testosterone and oestradiol values did not change. The resistance index of both intratesticular arteries significantly decreased (p=0.012 and 0.005 for right and left testes respectively). The results of this study confirmed the positive effect of exogenous hMG on testicular blood flow, but failed to demonstrate any effect of hMG treatment on NO levels in the seminal plasma in infertile males.

Assessment of right ventricular function by strain rate imaging in chronic obstructive pulmonary disease.

The purpose of the current study was to compare right ventricular (RV) myocardial wall velocities (tissue Doppler imaging) and strain rate imaging (SRI) parameters with conventional echocardiographic indices evaluating RV function in chronic obstructive pulmonary disease (COPD) patients. In total, 39 patients with COPD and 22 healthy subjects were included in the current study. Seventeen patients had pulmonary artery pressure <35 mmHg (group I) and 22 patients had pulmonary artery pressure >35 mmHg (group II). Tissue Doppler imaging, strain and strain rate (SR) values were obtained from RV free wall (FW) and interventricular septum. Respiratory function tests were performed (forced expiratory volume in one second/vital capacity (FEV(1)/VC) and carbon monoxide diffusion lung capacity per unit of alveolar volume (D(L,CO)/V(A))). Strain/SR values were reduced in all segments of group II patients compared with group I patients and controls with lowest values at basal FW site. A significant relationship was shown between peak systolic SR at basal FW site and radionuclide RV ejection fraction. A significant relationship was shown between peak systolic SR at basal FW site and D(L,CO)/V(A) and FEV(1)/VC. In conclusion, in chronic obstructive pulmonary disease patients, strain rate imaging parameters can determine right ventricular dysfunction that is complementary to conventional echocardiographic indices and is correlated with pulmonary hypertension and respiratory function tests.

Assessment of severity of mechanical prosthetic mitral regurgitation by transoesophageal echocardiography.

OBJECTIVE: To evaluate the ability of colour Doppler transoesophageal echocardiography (TOE) to assess quantitatively prosthetic mitral valve insufficiency. METHODS: 47 patients were studied with multiplane TOE and cardiac catheterisation. Proximal jet diameter was measured as the largest diameter of the vena contracta. Regurgitant area was measured by planimetry of the largest turbulent jet during systole. Flow convergence zone was considered to be present when a localised area of increased systolic velocities was apparent on the left ventricular side of the valve prosthesis. Pulmonary vein flow velocity was measured at peak systole and diastole. RESULTS: Mean (SD) proximal jet diameter was 0.63 (0.16) cm, with good correlation with angiographic grades (r = 0.83). Mean (SD) maximum colour jet area was 7.9 (2.5) cm2 (r = 0.69) with worse correlation if a single imaging plane was used for measurements (r = 0.62). The ratio of systolic to diastolic peak pulmonary flow velocity averaged 0.7 (1.3) cm (r = -0.66) with better correlation (r = -0.71) if patients with atrial fibrillation were excluded. Mean (SD) regurgitant flow rate was 168 (135) ml/s and regurgitant orifice area was 0.56 (0.43) cm2, with good correlation with angiography (r = 0.77 and r = 0.78, respectively). CONCLUSIONS: TOE correctly identified angiographically severe prosthetic mitral regurgitation, mainly by the assessment of the flow convergence region and the proximal diameter of the regurgitant jet.

Transesophageal dobutamine stress echocardiography with tissue Doppler imaging for detection and assessment of coronary artery disease.

BACKGROUND: Transesophageal dobutamine stress echocardiography (T-DSE) has been shown to be a sensitive and specific technique for the detection of myocardial ischemia. A major limitation of echocardiographic study interpretation, however, is the subjective visual analysis of endocardial motion and wall thickening, which is only semiquantitative. METHODS: To analyze whether T-DSE with the use or tissue Doppler imaging (TDI) during graded dobutamine infusion may be useful to detect and quantify stress-induced myocardial ischemia by changes in myocardial velocities, 70 patients undergoing coronary arteriography were studied with T-DSE and TDI. Midesophageal and transgastric short- and long-axis images were obtained at each level of dobutamine infusion. T-DSE was successful in 67 patients (96%). Baseline resting pulsed and color peak systolic (S) and early diastolic (E) velocities of the anterior, septal, lateral, and inferior walls were examined. RESULTS: Pulsed and color TDI correlated well at rest and after stress. Fifteen patients had a normal response to dobutamine, and 52 patients had inducible ischemia by two-dimensional criteria. In the normal group, there was a significant dose-dependent increase in S and E velocities. Compared with those in the normal group, patients with coronary artery disease (CAD) had lower resting S and E velocities and blunted S wave increase or E wave decrease during DSE. CONCLUSIONS: T-DSE with TDI is a feasible and accurate test for the quantitative assessment of patients with CAD who have impaired augmentation of systolic and diastolic myocardial velocities during dobutamine infusion.

Diagnostic accuracy and prognostic implications of stress testing for coronary artery disease in the elderly.

BACKGROUND: The aim of this study was to define the diagnostic accuracy and the prognostic significance of stress electrocardiography (ECG) and of thallium-201 single-photon emission computed tomography (SPECT) in determining the incidence of coronary artery disease (CAD) in an elderly population. METHODS: A selected series of 132 patients (90 males, mean age 72.4 years; 42 females, mean age 68.2 years) hospitalized because of cardiac events associated with suspected CAD, underwent stress ECG and thallium-201 testing; as endpoints we considered the heart rate and the appearance of clinical symptoms or ST segment depression. Patients unable to develop an adequate exercise workload, were tested with dipyridamole. All patients also underwent coronary angiography following the stress test. One hundred and twenty-four patients had a mean follow-up of 2 years. Endpoints included subsequent coronary events or new serious disease. The sensitivity, specificity, diagnostic accuracy, and positive and negative predictive values of both ECG and of thallium-201 SPECT were calculated. RESULTS: ECG findings were positive in 102 patients and coronary angiography confirmed the presence of CAD in 92 of them; ECG findings were negative in 30 patients, but only 14 were free from obstructive coronary lesions. Thallium-201 SPECT findings were positive in 112 patients (coronary angiograms confirmed CAD in 101) and negative in 20 patients (in 13 of whom angiography confirmed the absence of disease). The sensitivity of the stress tests was quite good: 85.1% for ECG and 93.5% for thallium-201 SPECT; conversely, the specificity of ECG was superior to that of SPECT (58.3 vs 54.1%). The sensitivity of both techniques was superior in males than in females and seemed to correlate with the extent of CAD. CONCLUSIONS: The diagnostic accuracy of thallium-201 SPECT was 86.3% whereas that of ECG was 80.3%. Considering the overall cardiac events, the predictive value of SPECT was superior to that of ECG both in terms of the positive value (54 vs 51%, p = NS) and, more importantly, in terms of the negative value (84 vs 62%, p < 0.03). In fact, patients with normal thallium images were at low risk for future cardiac events.

Transoesophageal echocardiographic visualization of renal cyst mimicking aortic aneurysm.

We report a tricky case of a 63-year-old man with previous coronary artery bypass graft surgery in whom transoesophageal echocardiography revealed a voluminous echolucent cavity simulating aortic ectasia but that proved to be of nephrogenic origin.

Assessment of regional left ventricular function during exercise test with pulsed tissue Doppler imaging.

To investigate whether mitral annular velocity, measured by tissue Doppler imaging (TDI), is able to get a feasible quantitative evaluation of global and regional left-ventricular function during exercise test, 29 patients with previous uncomplicated myocardial infarction were studied by exercise echocardiography. All patients underwent coronary arteriography within 10 days of stress echocardiography. All of them were in sinus rhythm and had no right or left bundle branch block or significant mitral regurgitation as observed by left ventriculography. A total of 12 patients had anteroseptal and/or posteroseptal wall asynergies and left anterior descending involvement; 9 patients had lateral and/or posteroinferior asynergies and left circumflex coronary artery involvement; 8 patients had inferior and posteroseptal wall asynergies and right coronary artery involvement. Twelve subjects of same age and sex with normal cardiovascular findings were selected as a control group. TDI sample volumes were set on the mitral annuli corresponding to anteroseptal, posterior, posteroseptal, lateral, anterior, and inferior wall in 4-chamber, 2-chamber, and long-axis views. There was a significant correlation between the left-ventricular ejection fraction (0.41 +/- 0.8) and the means of the systolic (S) values (6.1 +/- 0.9 cm/sec, r = 0.83, p < 0.01). The mean S at the sites corresponding to the infarct regions (5.5 +/- 0.4 cm/sec) was significantly lower than the control group (11 +/- 0.8 cm/sec, p < 0.001). After stress, in patients with multivessel disease, S values corresponding to remote regions were significantly lower (p < 0.01) compared with control subjects. Thus, the parameters obtained from mitral annular velocities with pulsed TDI in patients with previous myocardial infarction reflect left ventricular asynergy corresponding to the infarct regions and reversible regional dysfunction after exercise.

Transthoracic and transesophageal echocardiography in the hemodynamic assessment of patients with congestive heart failure.

All methods for estimating the severity of heart failure, such as clinical and radiographic examination, measures of ventricular performance, and exercise capacity, when used independently, have major limitations. Echocardiography can be used, not only to assess left-ventricular ejection fraction but also other determinants of prognosis (i.e., left-ventricular size and shape, estimation of left atrial and pulmonary artery pressures, right side involvement). The availability of continuous-wave Doppler has permitted us to evaluate pulmonary artery systolic pressure from tricuspid regurgitation, and this contributes to additional powerful data. In long-standing heart failure, pulmonary artery wedge pressure is a predictor of survival, and aggressive therapy to reduce wedge pressure improves survival. Noninvasive estimation of left-atrial pressure and left-ventricular filling pressure have been attempted by continuous-wave Doppler echocardiography in patients with heart failure and mitral regurgitation and by tissue Doppler imaging at the mitral annulus level. A significant relation has been reported between profiles of pulmonary venous flow and left-atrial pressure, but pulmonary venous flow indexes can be better assessed by transesophageal echocardiography (TEE) in terms of detection rate. It has recently been recognized that TEE can provide valuable information on intracardiac hemodynamics and ventricular function. Two-dimensional evaluation of ventricular function and pulsed- and continuous-wave Doppler recordings from the pulmonary artery, pulmonary vein, and mitral inflow are combined to provide these data, which are both qualitative and quantitative, and permit estimation of ventricular ejection fraction, left-atrial pressure, and cardiac output. It would be important to be able to stratify patients with congestive heart failure according to groups with the highest risk for early death because heart transplantation or aggressive medical treatment could be specifically applied to this population. Serial echocardiographic evaluations of the classic variables of systolic left-ventricular function as well as Doppler transmitral flow may be useful in monitoring the progression of the disease and the effects of medical treatment. The degree of pulmonary hypertension is independently associated with the restrictive left-ventricular diastolic filling pattern and with the degree of functional mitral regurgitation. Future studies on the impact of these hemodynamic variables on the outcome of patients with left-ventricular dysfunction are desirable.

Usefulness of transesophageal echocardiography in the assessment of aortic dissection.

The acute dissection of the ascending aorta requires prompt and reliable diagnosis to reduce the high risk of mortality; in addition, prognosis is influenced by long-term complications. The aim of this article is to discuss transesophageal echocardiography (TEE) and (1) its diagnostic accuracy in the presurgical evaluation of patients, (2) its role in reducing time of diagnosis and surgery, and (3) its ability to reduce hospital mortality. TEE has also been tested as a screening method in the postsurgical follow-up of these patients. The retrospective investigation concerns a sample of 80 cases of acute dissection of the aorta, submitted for surgical intervention from April 1986 to February 1999. TEE has allowed a precise estimation of aortic diameters and optimal visualization of intimal flap and tear entry with a fine distinction between true and false lumen. A direct comparison of the results of TEE and of transthoracic echocardiography has demonstrated that some elements (visualization of flap and diameters in descending aorta, sites of entry and reentry, direction of jet trough intimal tears, phasic intimal flap movement, diastolic collapse of flap on the valvular plane, false lumen thrombosis, coronary involvement, intramural hematoma, and aortic fissuration) were identified only by TEE, whereas other additional diagnostic elements (cardiac tamponade, aortic valve insufficiency, left ventricular function) show a similar pattern of significance. Routine employment of this method has confirmed a reduction of hospitalization time (about 1.5 hours of waiting time), and hospital mortality has changed from 42.8% to 17.3%. In the follow-up of patients operated on for aortic dissection, fundamental information may be obtained from TEE (assessment of the progression of thrombosis in the false lumen with its complete obliteration and modifications in aortic diameter with a consequent, possible worsening of aortic valve insufficiency). In conclusion, our study demonstrated that TEE may provide fast and efficient detection of acute aortic dissection. In the postsurgical follow-up, TEE has confirmed detection of major complications that can influence long-term prognosis and may be proposed as a method with easy access-one that is repeatable and inexpensive for the screening of aortic dissection surgical patients.

Value of transesophageal dobutamine stress echocardiography in assessing coronary artery disease.

The introduction of digital echocardiography has significantly enhanced our ability to select the best set of frames for analysis. However, despite the beneficial attributes of transthoracic dobutamine stress echocardiography, poor quality 2-dimensional images continue to be a significant limiting factor in patients with chest deformities, severe chronic obstructive lung disease, marked obesity, and previous chest surgery. Transesophageal echocardiography provides a new window to monitor left ventricular contractility without the interference of bone and air-filled structures of the thoracic cage. The transesophageal dobutamine stress test is a logical but poorly explored modality to image/stress the heart in certain patients with known or suspected myocardial ischemia. Overall sensitivity (< or = 85%) and specificity (< or = 95-100%) of transesophageal dobutamine stress echocardiography appear to be similar to that of previous transthoracic studies, although no direct comparison has been accomplished between transthoracic and transesophageal stress images. False negative transesophageal dobutamine stress echocardiography results have been described in patients with single-vessel disease in whom ischemic regions may not have been visualized throughout the entire study. False positive study results may be present in patients with hypertension and myocardial hypertrophy that may have signs and symptoms of myocardial ischemia in absence of obstructive disease of the epicardial coronary arteries, presumably related to either microvascular disease or impaired vasodilatory reserve. The proportion of patients with coronary artery disease who need a transesophageal examination for reliable assessment of echocardiographic response to stress varies depending on the operators' skills, the interpreters' experience, and the use of videotape or digitizing systems for image analysis. Although clinically useful in its present transthoracic and transesophageal form, a major limitation of dobutamine stress echocardiographic study is the subjective visual interpretation of endocardial motion and wall thickening, which is only semiquantitative. Color kinesis and tissue Doppler imaging (TDI) are 2 novel echocardiographic techniques that color code endocardial motion and myocardial velocity online and have the potential to objectively quantify regional left ventricular function. Quantitative standardization of transthoracic and transesophageal data interpretation, such as establishing endocardial motion by color kinesis or velocity thresholds by TDI for an abnormal segmental response to stress, has the potential to decrease interobserver variability and increase interinstitutional agreement.

Role of the central endogenous opiate system in patients with syndrome X.

BACKGROUND: To evaluate the role of the endogenous opioid system (EOS) in abnormal pain perception in patients with syndrome X, we used a neuroendocrine approach, evaluating plasmatic luteinizing hormone (LH) changes after naloxone, a competitive antagonist of opioid receptors able to unblock tonic EOS inhibition on gonadotropin release. Thus LH response to naloxone test indicates the central EOS activity on hypothalamic luteinizing hormone-releasing hormone (LH-RH) inhibitory opioid receptors. METHODS: Ten patients with syndrome X, 10 age-matched male patients with coronary artery disease (CAD), and 10 normal subjects were analyzed. Naloxone tests were performed between 8 and 9 am. Basal beta-endorphin and LH levels were determined on 4 blood samples at 20-minute intervals; after naloxone (0.1 mg/kg intravenously in 4 minutes), LH was measured on 8 samples at 15-minute intervals. In all patients the test was also performed after LH-RH administration. Anginal pain on exercise testing was subjectively scored on a 1 to 10 analogic scale and wall motion abnormalities were quantified by a wall motion score index. RESULTS: Significant differences were found in LH release after naloxone (CAD 260.3 +/- 42.6 vs syndrome X 151.6 +/- 48.5 mIU/mL, P <.05), angina score (CAD 5.5 +/- 1.3 vs syndrome X 7.2 +/- 1.7, P <.05), and wall motion abnormalities (CAD 3.6 +/- 1. 2 vs syndrome X 2.8 +/- 1.9, P <.05). CONCLUSIONS: The reduced LH release after naloxone in syndrome X, with a normal LH-RH response, suggests a lower central EOS activity, which may be related to the higher anginal pain perception.