Faculty Bibliography

PURPOSE: To retrospectively identify pulmonary arterial (PA) flow parameters measured with phase-contrast magnetic resonance (MR) imaging that allow noninvasive diagnosis of chronic PA hypertension (PAH). MATERIALS AND METHODS: The study was HIPAA compliant and was approved by the institutional review board; a waiver of informed consent was obtained. Fifty-nine patients (49 female patients; mean age, 46 years; range, 16-85 years) known to have or suspected of having PAH underwent breath-hold phase-contrast MR imaging and right-sided heart catheterization (RHC). The presence of PAH (mean pulmonary artery pressure [mPAP], >25 mm Hg) was confirmed in 42 patients. Parameters, including PA areas, PA strain, average velocity, peak velocity, acceleration time, and ejection time, were measured in each patient by investigators blinded to RHC results. These measurements were correlated with mPAP, systolic pulmonary artery pressure (sPAP), and pulmonary vascular resistance index (PVRI). The diagnostic ability of phase-contrast MR imaging to depict PAH was quantified. Statistical tests included Spearman rho coefficients, receiver operating characteristic curve analysis, and Bland-Altman plots. RESULTS: Results showed average velocity to have the best correlation with mPAP, sPAP, and PVRI (r = -0.73, -0.76, and -0.86, respectively; P < .001). Average velocity (cutoff value = 11.7 cm/sec) revealed PAH with a sensitivity of 92.9% (39 of 42) and a specificity of 82.4% (14 of 17). Sensitivity and specificity for the minimum PA area (cutoff value = 6.6 cm(2)) were 92.9% (39 of 42) and 88.2% (15 of 17), respectively. CONCLUSION: The average blood velocity throughout the cardiac cycle is strongly correlated with pulmonary pressures and resistance.

Pulmonary artery sarcomas are rare neoplasms of the pulmonary artery that are often confused with chronic thromboembolic disease, as both diseases have similar presentations. In patients with presumed chronic thromboembolic pulmonary hypertension, certain clinical and imaging characteristics may suggest the alternative diagnosis of pulmonary artery sarcoma. In this article we present a case of a man initially diagnosed with chronic thromboembolic pulmonary hypertension, but who was later found to have pulmonary artery sarcoma. We review the distinguishing characteristics of the two diseases and discuss possible treatment strategies.

STUDY OBJECTIVE: To differentiate the clinical, radiographic, and physiologic profile in patients with sarcoidosis with and without pulmonary hypertension. DESIGN: Retrospective survey. SETTING: Tertiary care center. PATIENTS: One hundred six patients with sarcoidosis were classified by two-dimensional echocardiography into two groups: group 1, 54 patients with pulmonary hypertension; group 2, 52 patients without pulmonary hypertension. INTERVENTIONS: Patients underwent two-dimensional and Doppler echocardiography, chest radiography (CXR), pulmonary function testing, and arterial oxygen saturation determination, and the test results were compared between the two groups. Statistical analysis was performed using independent-sample t test and chi2 test, as appropriate; p < 0.05 was considered to be significant. RESULTS: Predicted spirometric values and lung diffusing capacity were significantly lower in patients in group 1 compared to patients in group 2: FVC, 54% vs 64% (p = 0.0065), FEV(1), 47% vs 61% (p = 0.0005), forced expiratory flow, midexpiratory phase, 35% vs 52% (p = 0.0363), and single-breath diffusing capacity of the lung for carbon monoxide (D(LCO)sb), 39% vs 54% (p = 0.0001). Sixty percent of patients in group 1 had radiographic Scadding stage 4 sarcoidosis, while no radiographic stage predominated in group 2. Arterial oxygen saturation, need for oxygen supplementation, and degree of desaturation after exercise did not differ between groups. CONCLUSIONS: The presence of pulmonary hypertension in patients with sarcoidosis is associated with higher prevalence of stage 4 sarcoidosis by CXR and lower predicted spirometric and D(LCO)sb measurements.

Nitroglycerin and dipyridamole are two commonly available and well tolerated vasoactive medications. Their acute hemodynamic effects in patients with pulmonary arterial hypertension are not well defined in the current literature. The authors retrospectively analyzed the acute hemodynamic effects of IV nitroglycerin, dipyridamole, and epoprostenol in 59 patients with pulmonary arterial hypertension as determined by changes from baseline in systemic and pulmonary hemodynamic parameters. Statistical analysis was performed using the independent sample t test. A p value <0.05 was considered significant. Nitroglycerin is predominantly a vasodilator of the pulmonary vasculature with moderate systemic vasodilator effect, while dipyridamole is primarily a positive inotropic agent. Epoprostenol is a potent vasodilator of both pulmonary and systemic vessels and a strong positive inotropic agent. Nitroglycerin and dipyridamole may be useful in the acute management of pulmonary arterial hypertension.

Pulmonary arterial hypertension is a severe disease with poor prognosis, caused by obliteration of the pulmonary vasculature as a result of pulmonary-vascular remodeling, active vasoconstriction and in situ thrombosis. Left untreated, pulmonary arterial hypertension results in right-ventricular failure and death. There has been dramatic progress in the treatment of pulmonary arterial hypertension during recent years. A remarkable number of randomized-controlled trials with agents known to target specific abnormalities present in pulmonary arterial hypertension have been completed. Most commonly, therapeutic efficacy was judged by the ability of the drug under study to improve exercise capacity and to decrease the rate of severe complications. Completed clinical trials have mainly evaluated patients with relatively advanced disease. Despite these advances, responses to therapy in pulmonary arterial hypertension are not uniformly favorable and frequently incomplete. In addition, the methods of delivery and the adverse effect profile of the currently available pulmonary arterial hypertension-specific drugs create further management difficulties. Based on newly identified pathobiologic abnormalities in the pulmonary vasculature, future studies are likely to focus on the discovery of new therapeutic targets. Clinical trial design will continue to evolve in an attempt to enable inclusion of patients with less advanced disease and evaluation of treatment combinations or comparisons of the currently approved drugs.