Ancillary findings assessed by ventilation/perfusion tomography. Impact and clinical outcome in patients with suspected pulmonary embolism.

UNLABELLED: Ventilation/perfusion tomography (V/P SPECT) is a recommended method for diagnosing and follow-up of pulmonary embolism (PE). Moreover, it is possible to recognize other pathologies in addition to PE, such as pneumonia, COPD and left heart failure (LHF). The objective of this prospective study was to identify frequency of ancillary findings among patients with suspected PE. Patients, material, method: 331 consecutive patients with suspected PE were examined and classified with V/P SPECT. Patients were followed up clinically and by means of other laboratory tests. RESULTS: 80 patients had a normal V/P SPECT and no clinical consequences in the follow-up. PE had 104 patients: 23 of them had also additional findings. Among the remaining 147 patients, pneumonias were shown in 82, acute in 75 patients and 7 had chronic post inflammatory state. COPD was present in 42 patients, in 3 combined with pneumonia. Sign of LHF was observed in 10: in 7 the acute LHF diagnosis was established, 3 were classified as having a chronic cardiopulmonary disease. Furthermore, in 16 patients, the V/P pattern was suggestive of a tumour. The clinical outcomes were 6 lung tumours, 3 empyema, one sarcoidosis, 2 were unclarified and 4 were lost in the follow-up. CONCLUSION: V/P SPECT identifies a high prevalence of other cardiopulmonary diseases among patients with a clinical suspicion of PE. Ancillary findings with V/P SPECT clarified patients' symptoms and had an impact on the treatment. These findings were verified by a clinical outcome by the follow-up over three months.

Genetic variants of microsomal epoxide hydrolase and glutamate-cysteine ligase in COPD.

The genetic factors that contribute to the development of chronic obstructive pulmonary disease (COPD) are poorly understood. Many candidate genes have been proposed, including enzymes that protect the lung against oxidative stress, such as microsomal epoxide hydrolase (EPHX1) and glutamate-cysteine ligase (GCL). To date, most reported findings have been for EPHX1, particularly in relation to functional variants associated with fast and slow metabolism of epoxide intermediates. The present study aimed to identify any association of variation in these genes with COPD susceptibility or severity. In total, 1,017 white COPD patients and 912 nondiseased age and sex matched smoking controls were genotyped for six single nucleotide polymorphisms (SNPs) in EPHX1 (including the fast and slow variants and associated haplotypes), and eight SNPs in the two genes encoding GCL. GCL is a rate-limiting enzyme in the synthesis of glutathione, a major contributor to anti-oxidant protection in the lung. No association of variation was found in EPHX1 or GCL with susceptibility to COPD or disease severity. This is the largest reported study to date and is well powered to detect associations that have been previously suggested. The current data indicate that these genetic variants are unlikely to be related to susceptibility or disease severity in white chronic obstructive pulmonary disease patients.

Value of chest radiography in phenotyping chronic obstructive pulmonary disease.

The objectives of the present study were to reappraise chest radiography for the diagnosis of emphysema, using computed tomography (CT) as the reference standard, and to establish whether or not chest radiography is useful for phenotyping chronic obstructive pulmonary disease (COPD). Patients (n = 154) who had undergone posteroanterior and lateral chest radiography and CT for diagnostic purposes were studied. CT data were scored for emphysema using the picture-grading method. Chest radiographs were examined independently by five raters using four criteria for emphysema that had been validated against lung pathology. These criteria were then used to assess the prevalence of emphysema in 458 COPD patients. Patients with and without evidence of emphysema were compared with regard to age, sex, smoking history, body mass index (BMI), forced expiratory volume in one second (FEV(1)), diffusing capacity of the lung for carbon monoxide (D(L,CO)) and health status. Chest radiography yielded a sensitivity of 90% and a specificity of 98% for emphysema. Of the 458 COPD patients, 245 showed radiological evidence of emphysema. Emphysemic patients had a significantly lower BMI, FEV(1) and D(L,CO), greater restriction of physical activity and worse quality of life than nonemphysemic patients. There was no difference across the two groups with regard to age, sex or smoking history. Chest radiography is a simple means of diagnosing moderate-to-severe emphysema. It is useful in phenotyping chronic obstructive pulmonary disease and may aid physicians in their choice of treatment.

Dyspnoea and hypoxaemia after lung surgery: the role of interatrial right-to-left shunt.

After lung surgery, some patients complain of unexplained increased dyspnoea associated with hypoxaemia. This clinical presentation may be due to an interatrial right-to-left shunt despite normal right heart pressure. Some of these patients show postural dependency of hypoxaemia, whereas others do not. In this article, the pathogenesis and mechanisms involved in this post-surgical complication are discussed, and the techniques used for confirmation and localisation of shunt are reported. An invasive technique, such as right heart catheterisation with angiography, was often used in the past as the diagnostic procedure for the visualisation of interatrial shunt. As to noninvasive techniques, a perfusion lung scan may be used as the first approach as it may detect the effect of the right-to-left shunt by visualising an extrapulmonary distribution of the radioactive tracer. The 100% oxygen breathing test could also be used to quantify the amount of right-to-left shunt. Particular emphasis is given to newer imaging modalities, such as transoesophageal echocardiography, which is minimally invasive but highly sensitive in clearly visualising the atrial septum anatomy. Finally, the approach to closure of the foramen ovale or atrial septal defect is discussed. Open thoracotomy was the traditional approach in the past. Percutaneous closure has now become the most used and effective technique for the repair of the interatrial anatomical malformation.

Diagnostic value of gas exchange tests in patients with clinical suspicion of pulmonary embolism.

OBJECTIVE: To assess the value of parameters derived from arterial blood gas tests in the diagnosis of pulmonary embolism. METHOD: We measured alveolar-arterial partial pressure of oxygen [P(A-a)O2] gradient, PaO2 and arterial partial pressure of carbon diaxide (PaCO2) in 773 consecutive patients with suspected pulmonary embolism who were enrolled in the Prospective Investigative Study of Acute Pulmonary Embolism. DIAGNOSIS: The study design required pulmonary angiography in all patients with abnormal perfusion scans. RESULTS: Of 773 scans, 270 were classified as normal/near-normal and 503 as abnormal. Pulmonary embolism was diagnosed by pulmonary angiography in 312 of 503 patients with abnormal scans. Of 312 patients with pulmonary embolism, 12, 14 and 35% had normal P(A-a)O2, PaO2 and PaCO2, respectively. Of 191 patients with abnormal scans and negative angiograms, 11, 13 and 55% had normal P(A-a)O2, PaO2 and PaCO2, respectively. The proportions of patients with normal/near-normal scans who had normal P(A-a)O2, PaO2 and PaCO2 were 20, 25 and 37%, respectively. No differences were observed in the mean values of arterial blood gas data between patients with pulmonary embolism and those who had abnormal scans and negative angiograms. Among the 773 patients with suspected pulmonary embolism, 364 (47%) had prior cardiopulmonary disease. Pulmonary embolism was diagnosed in 151 (41%) of 364 patients with prior cardiopulmonary disease, and in 161 (39%) of 409 patients without prior cardiopulmonary disease. Among patients with pulmonary embolism, there was no difference in arterial blood gas data between patients with and those without prior CPD. CONCLUSION: These data indicate that arterial blood gas tests are of limited value in the diagnostic work-up of pulmonary embolism if they are not interpreted in conjunction with clinical and other laboratory tests.

Pulmonary retention of iodobenzyl-propanediamine in humans. Effect of cigarette smoking.

N,N,N'-trimethyl-N'-(2-hydroxy-3-methyl-5-iodobenzyl)-1,3-propanediamine (HIPDM), a synthetic basic compound with high affinity for lung tissue of various animal species, was labeled with 123I and injected into normal smokers (n = 9) and into asymptomatic smokers (n = 9). Time/activity curves were recorded for 90 min by gamma camera. HIPDM lung clearance was described by two exponential components. In smokers, the mean time of the first component, 10 +/- 1.4 min (mean +/- SEM), did not significantly differ from that of nonsmokers (9.7 +/- 0.9 min), whereas the mean time of the second component (12.9 +/- 0.6 h) was longer than that of nonsmokers (6.7 +/- 0.2 h). The intercept to the ordinate of the second exponential component was significantly higher in smokers (90.3 +/- 1.5%) than in nonsmokers (80.7 +/- 1.9%). Control studies in rabbits showed that, 2 min after intravenous injection, 95% of HIPDM is taken up by the lung; time/activity curves were similar to those obtained in humans. The longer pulmonary persistence of HIPDM in smokers may reflect an increased number of cellular binding sites or may be the expression of hindered HIPDM biotransformation. The rabbit can be used as a model to further investigate HIPDM kinetics in relation to lung dysfunction.

Fatal peripheral airway cystic disease in a young woman.

Diffuse cystic transformation of both lungs was rapidly fatal in a 33-year-old woman. This disorder, a rare congenital condition in infants, has apparently not been described in adulthood.

The radiologic distinction of cardiogenic and noncardiogenic edema.

Improvement in the ability to determine the specific cause of any given case of pulmonary edema would lead to more rapid and definitive treatment. "Wedge" pressures and measurements of cardiac output derived from Swan-Ganz catheterization assist in making this determination, but the procedure is invasive, expensive, associated with complications, and not infrequently inaccurate. A plain chest film is, however, almost invariably available in all patients with pulmonary edema, and as shown in this study, the cause of the edema can be determined with a high degree of accuracy by careful attention to certain radiographic features. An independent two-observer study was performed on 216 chest radiographs of 61 patients with cardiac disease, 30 with renal failure or overhydration, and 28 with capillary permeability edema. Three principal and seven ancillary features have been identified, all of which are statistically significant and permit the cause of the edema to be determined correctly in a high percentage of cases. The three principal features are distribution of pulmonary flow, distribution of pulmonary edema, and the width of the vascular pedicle. The ancillary features are pulmonary blood volume, peribronchial cuffing, septal lines, pleural effusions, air bronchograms, lung volume, and cardiac size. Differing constellations of these features occur, each of which is characteristic of a specific type of edema. Overall accuracy of diagnosis in this study ranged from 86% to 89%. The highest accuracy was obtained in distinguishing capillary permeability edema from all other varieties (91%), and the lowest in distinguishing chronic cardiac failure from renal failure (81%).

Results of en bloc resections for lung cancer.

The results of en bloc resection carried out in 33 patients with lung cancer involving the chest wall are described. Microscopic examination of the lung specimen revealed large cell anaplastic carcinoma in 14 cases, squamous carcinoma in 10, adenocarcinoma in 5, microcytoma and fibrosarcoma in 2 cases respectively. The 5 year survival, calculated according to the actuarial method, was 32%, only slightly lower than the 5 year overall survival observed in our survey. The long-term prognosis was essentially related to the presence of lymph node metastases, which were found to occur at a late stage of the clinical evolution.