Fumiko Deguchi

Thallium-201 myocardial SPECT findings at rest in sarcoidosis

In 41 patients with sarcoidosis (diagnosed according to criteria recommended by the Committee on Diffuse Pulmonary Disease, Ministry of Health and Welfare, Japan 1988), thallium-201 (201Tl) myocardial SPECT was performed to investigate: (1) the ability of201Tl SPECT to detect cardiac involvement of sarcoidosis with images recorded at rest and 2 hours later, and (2) the relationships between201Tl myocardial SPECT findings and the activity of sarcoidosis or endomyocardial biopsy findings. As to the abnormal findings in201Tl myocardial SPECT, (1) a low density area was seen in 13 of 41 cases (31.7%) and non-uniform uptake was found in 17 cases (41.5%), (2) the mean washout ratio (n=39) was 16.5±7.4%, which is significantly (p < 0.05) lower than that found in normal subjects, 23.9±7.5 % (n=10). Of the 19 patients judged visually to be normal, 5 patients had a reduced mean washout ratio less than 12%. Thus, the incidence of abnormal findings including all types of abnormality, on201Tl myocardial SPECT in sarcoidosis was 63.4% (26/41 cases). In studying the relationship between201Tl myocardial SPECT findings and the activity of sarcoidosis (as measured by the serum ACE (angiotensin converting enzyme) or lysozyme level, or the presence of more than 30% symphocyte fraction in BALF (broncho-alveolar lavage fluid)), 20 (80%) of 25 cases with201Tl abnormality were judged to be active sarcoidosis, while only 6 (37.5%) of 16 cases with normal findings on201Tl SPECT were judged to be active. This suggests that there is a significant (p < 0.01) relationship between the presence or absence of an abnormal finding on201Tl myocardial SPECT and the activity of sarcoidosis. Among 13 patients examined by endomyocardial biopsy, 10 patients had abnormal findings on201Tl myocardial SPECT and 7 of these 10 patients had no histological evidence of cardiac sarcoidosis. In all of these 7 patients, however, sarcoidosis was judged to be active. This suggest that endomyocardial biopsy is of limited value in the diagnosis of cardiac sarcoidosis.

Extravascular lung water measured with99mTc-RBC and99mTc-DTPA is increased in left-sided heart failure

Extravascular lung water (EVLW) was quantitatively measured in 81 patients consisting of 10 subjects with normal cardiac function and 71 patients with left-sided heart diseases, using99mTc-RBC as a non-diffusible indicator and99mTc-DTPA as a diffusible indicator in the equilibrium phase. EVLW averaged 3.0±1.4 (ml/kg, mean±SD) in subjects with normal cardiac function (n=10), 4.3±1.7 in New York Heart Association functional class I patients (n=30), 4.8±2.4 in NYHA functional class II patients (n=33) and 9.4±5.4 in NYHA functional class III (n=8) patients. EVLW was greater in NYHA class III than in normal controls or NYHA classes I or II (p < 0.01).Lung thermal volume (LTV) was also measured in 31 of the 81 patients using a double indicator dilution technique with sodium and heat. LTV averaged 6.0±1.2 (ml/kg) in normal subjects (n=4), 8.6±2.0 in NYHA functional class I patients (n=11), 9.7±3.0 in NYHA functional class II patients (n=13), and 15.9±8.2 in NYHA functional class III patients (n=3). The correlation between EVLW and LTV was significant (EVLW=0.79×LTV-72.8, r=0.80, p < 0.01). There were significant differences in EVLW/LTV ratio between NYHA class III (0.93±0.16) and NYHA class I (0.62±0.22) or class II (0.60±0.23). Thus, it was shown that EVLW was increased in left-sided heart failure and that LTV overestimated the EVLW.

Human Pulmonary Venous Return Curve: Effect of Dopamine

Pulmonary “venous” compliance (Cp“v”) and pulmonary arterial compliance (Cpa) were determined using radionuclide angiocardiography and a floating catheter in patients with various cardiac diseases. A pulmonary venous return curve was constructed from these measurements, and the effect of dopamine on the pulmonary venous return curve was evaluated. At the same time the pulmonary “venous” volume—pressure relationship and its response to dopamine was documented.