Noninvasive cardiac imaging in pulmonary hypertension.

Pulmonary artery hypertension is a rare disease with significant morbidity and mortality. Initial and serial noninvasive assessment of these patients can be accomplished with transthoracic echocardiography and/or cardiac magnetic resonance imaging. These complementary techniques provide the structural and functional information required to care for patients with pulmonary artery hypertension and are discussed in this review.

A change in serum myoglobin to detect acute myocardial infarction in patients with normal troponin I levels.

We sought to determine the sensitivity of a change in myoglobin for acute myocardial infarction (AMI) in patients who had normal levels of troponin I at presentation. Myoglobin increases as soon as 1 to 2 hours after symptom onset in AMI. The change in myoglobin may help identify AMI in patients with normal cardiac levels of troponin I on admission. A total of 817 consecutive patients who were examined in the emergency department for possible AMI were studied. In patients whose electrocardiograms were nondiagnostic, we measured levels of myoglobin and cardiac troponin I at presentation, at 90 minutes, and at 3 and 9 hours. Patients whose initial levels of myoglobin (<200 ng/ml) and cardiac troponin I (<0.4 ng/ml) were normal underwent receiver-operating characteristic curve analysis to determine the best cutpoint for a myoglobin increase from 0 to 90 minutes. Overall, 75 patients (9%) were diagnosed with AMI, including 27 patients with normal cardiac levels of troponin I at presentation. An increase of 20 ng/ml of myoglobin from 0 to 90 minutes provided maximal diagnostic utility in patients who did not have increased levels of myoglobin or cardiac troponin I at presentation. In the absence of an increased level of cardiac troponin I or myoglobin at presentation in the emergency department, a change >or=20 ng/ml of myoglobin at 90 minutes produced 83.3% sensitivity, 88.6% specificity, and 99.5% negative predictive value for AMI. The combined sensitivity of levels of cardiac troponin I and myoglobin and a change >or=20 ng/ml of myoglobin over 90 minutes was 97.3%. In emergency department patients with normal cardiac levels of troponin I at presentation, a change in myoglobin provides a highly accurate diagnosis of AMI within 90 minutes.

Cardiac chagas disease masquerading as an acute myocardial infarction.

Although myocardial infarction is most often the manifestation of epicardial coronary artery disease, Chagas heart disease due to chronic Trypanasome Cruzi infection may present with a syndrome of chest pain and elevations in markers of cardiac myonecrosis. In the setting of an increasingly diverse global population and immigration of peoples from endemic areas of Trypanasome Cruzi, it is important to be aware of the myriad cardiac manifestations of Chagas disease.

Volume of pleural fluid required for diagnosis of pleural malignancy.

STUDY OBJECTIVES: To determine if the diagnosis of pleural malignancy is dependent on the volume of pleural fluid sampled. DESIGN AND SETTING: Single-center retrospective chart review. PATIENTS: Two hundred eighty-two patients who underwent diagnostic thoracentesis between October 1, 1998, and June 30, 1999. INTERVENTIONS: Charts were analyzed for volume of fluid, pathologic and clinical diagnoses, and demographics. Patients were classified into quartiles based on the volume of pleural fluid collected. Sensitivity and negative predictive value (NPV) were calculated for each quartile for diagnosis of pleural malignancy by cytology of pleural fluid. Further analyses were done regarding the effect of sex, race, age, smoking history, and personal history of malignancy on diagnosis. RESULTS: In total, 374 samples from 282 patients were identified (140 men and 142 women). Pleural malignancy within 6 months of initial thoracentesis was diagnosed in 99 patients (35.1%). No differences were detected for sensitivity and NPV for diagnosis of pleural malignancy between any two quartiles (p > 0.05). Samples collected from women had a higher sensitivity for predicting pleural malignancy (p = 0.0011), and those collected from nonsmokers had a slightly higher but not statistically significant sensitivity for predicting pleural malignancy (p = 0.057). Samples collected from subjects with no history of malignancy had a significantly higher NPV than samples collected from subjects with a history of malignancy (p < 0.001). After adjusting for these demographic and medical history factors, the associations of the pleural fluid volume quartiles with sensitivity and NPV did not change. CONCLUSION: The sensitivity for diagnosis of pleural malignancy is not dependent on the volume of pleural fluid extracted during thoracentesis.