Intracoronary artery thrombus formation in unstable angina: a clinical, biochemical and angiographic correlation.

OBJECTIVES: We examined the relation between the level of urinary fibrinopeptide A and the presence of angiographic intracoronary thrombus in patients with unstable angina to determine whether this marker predicts active thrombus formation. BACKGROUND: Although it is known that thrombus plays a role in acute ischemic syndromes, a noninvasive method to predict its presence in individual patients with unstable angina has not been determined. Fibrinopeptide A is a polypeptide cleaved from fibrinogen by thrombin and thus is a sensitive marker of thrombin activity and fibrin generation. METHODS: Angiographic thrombus, graded 0 to 4, and the presence of ST segment depression or T wave inversions, or both, on the electrocardiogram (ECG) were related to fibrinopeptide A levels in 24 patients with rest angina of new onset, 18 with crescendo angina, 19 with stable angina and 9 with chest pain but without coronary artery disease. All patients had chest pain within the 24 h of sample acquisition. RESULTS: The angiographic incidence of thrombus was significantly higher in patients with new onset of rest angina (67%, p < 0.001) and crescendo angina (50%, p < 0.001) as were fibrinopeptide A levels (p = 0.002). Fibrinopeptide A levels correlated significantly (p < 0.001) with the presence of a filling defect (grade 4 intracoronary thrombus) or contrast staining (grade 3). All patients with fibrinopeptide A > or = 8 ng/mg creatinine showed grade 3 to 4 thrombus and 15 of 16 patients with levels > or = 6.0 ng/mg creatinine exhibited angiographic evidence of thrombus (13 with grades 3 to 4). Patients with reversible ST changes on the ECG had significantly higher levels of fibrinopeptide A (p < 0.001), and ST changes correlated significantly with the presence of angiographic thrombus (p < 0.001). Nonetheless, a significant minority of patients with unstable angina had neither angiographic nor biochemical evidence of thrombus. CONCLUSIONS: Elevated fibrinopeptide A levels in unstable angina reflected active intracoronary thrombus formation and were present in patients with angina of new onset as well as crescendo angina. Reversible ST changes are accompanied by thrombin activity and angiographic thrombus formation. However, a sizable percentage of patients with unstable angina had no evidence of thrombus and these patients may have had transient platelet aggregation without fibrin thrombus formation.

Broncholithiasis: CT features in 15 patients.

Broncholithiasis is a disorder characterized by peribronchial calcific nodal disease that either erodes into an adjacent bronchus or distorts the bronchi. The key radiologic finding is a calcified endobronchial or peribronchial lymph node. To determine the CT findings of broncholithiasis, we retrospectively reviewed the chest radiographs and CT scans of 15 patients with proved broncholithiasis. Ten patients had endobronchial nodes as proved by bronchoscopy, surgery, or lithoptysis. Broncholiths were identified on bronchoscopy in only five cases. Five patients had peribronchial nodes with associated bronchial distortion. Collimation of the CT scans varied; 1.0-cm-, 0.6-cm-, and 0.5-cm-thick sections were obtained. Three patients had both 1.0-cm- and 0.5-cm-thick sections. The calcified lymph node was identified on CT in all 15 patients. CT correctly localized six of 10 endobronchial nodes and four of five peribronchial nodes. Findings due to bronchial obstruction also were seen on CT; atelectasis (n = 11), infiltration (n = 4), bronchiectasis (n = 4), and air trapping (n = 1). An associated soft-tissue mass was not seen in any case. Difficulty in determining the relationship between lymph node and bronchus is due to volume averaging, which can be decreased by scanning thinner sections. CT can suggest the diagnosis of broncholithiasis and is useful when bronchoscopy does not show a broncholith.

Pleural cryptococcosis.

Pleural infection by Cryptococcus neoformans is uncommon and when present typically occurs in the immunocompromised host. We report two renal transplant patients who developed pleural cryptococcosis.

Imaging the diaphragm and its disorders.

Although a radiologic evaluation of the diaphragm is important in many clinical situations, visualization of the diaphragm is difficult because of its thinness, its domed contour, and its contiguity with abdominal soft tissues. Each clinical situation involving the diaphragm presents its own imaging difficulties, and each radiographic technique has advantages and disadvantages. No one modality is best for all situations. Often, several imaging modalities must be used to resolve the clinical question. The particular difficulties in diaphragmatic imaging are (1) distinguishing eventration from paralysis or hernia, (2) distinguishing lipoma from herniated omental fat, and (3) distinguishing unilateral paralysis from weakness and bilateral paralysis from respiratory fatigue. By selecting and applying the appropriate radiographic techniques, the radiologist can serve an essential role in assessing the disorders of the diaphragm.

Gated MR imaging of left atrial myxomas.

Two cases of left atrial myxoma were evaluated with magnetic resonance (MR) imaging. In both cases, the myxoma was clearly defined as to its location, origin, and size. In one case, the myxoma prolapsed through the mitral valve. Our study indicates that MR imaging is valuable in the diagnosis of myxomas.

The usefulness of chest radiographs obtained after a demonstrated perfusion scan defect in the diagnosis of pulmonary emboli.

The chest radiographs obtained within seven days of scintigraphic lung studies in 38 patients clinically suspected of having a pulmonary embolus were reviewed. Twenty-two of these patients also had pulmonary angiograms. Lung densities in areas of perfusion defects not present at the time of the scan studies were sought. Densities were observed in ten patients. These appeared 4 hours to five days later (mean 1.8 days). This sequence of events strongly supports the diagnosis of pulmonary embolism. Chest radiographs are recommended one day and, if normal, again three days after an abnormal perfusion lung scan, even if the pulmonary angiogram is normal. The delayed appearance of these lung densities will eliminate some non-emboli causes and thereby strengthen the diagnosis of embolism. If such densities are seen following a "normal" angiogram, it should be critically reviewed.

Endodermal sinus (yolk sac) tumors of the anterior mediastinum.

Seven cases of endodermal sinus tumor (yolk sac tumor) primary in the anterior mediastinum are added to the literature bringing to 21 the number of reported cases. This germ cell tumor should be included in the differential diagnosis of anterior mediastinal tumors. It has occurred in males 13--49 years old who are often systemically ill. Since this tumor almost always produces elevated levels of serum alpha-fetoprotein, a strong presumptive diagnosis is possible prior to biopsy. The prognosis is poor. The two disease-free survivors of the 21 reported cases were both treated with a combination of excision and chemotherapy.

Radiographic manifestations of broncholithiasis.

Calcifications within the lung may produce symptoms when they erode surrounding tissue and move. Lithoptysis, or symptoms related to bronchial obstructions may occur. Under these circumstances, careful attention should be paid to evidence of movement of a calcific focus and its relationship to the bronchi. Six examples are described. Tomography and bronchography are useful. Histoplasma organisms can be demonstrated in most broncholiths in an endemic area. In other areas this entity is becoming unusual, probably because of the declining incidence of tuberculosis. Not all hilar or parenchymal calcifications are innocuous.