This study examined the implications of left ventricular (LV) dilatation and increased pulmonary thallium uptake during adenosine-induced coronary hyperemia. The lung-to-heart thallium ratio in the initial images was significantly higher in patients with coronary artery disease (CAD) than normal subjects; 0.48 +/- 0.16 in 3-vessel disease (n = 16), 0.43 +/- 0.10 in 2-vessel disease (n = 20), 0.43 +/- 0.08 in 1-vessel disease (n = 16) and 0.36 +/- 0.05 in normal subjects (n = 7) (p less than 0.001, 0.09 and 0.06, respectively). There was a significant correlation between the severity and the extent of the perfusion abnormality (determined from the polar maps) and the lung-to-heart thallium ratio (r = 0.51 and 0.52, respectively, p less than 0.0002). There was also a significant correlation between lung thallium washout and lung-to-heart thallium ratio (r = 0.42, p = 0.0009) and peak heart rate (r = -0.49, p less than 0.0001). The LV dilatation was mostly due to an increase in cavity dimension (30% increase) and to a lesser extent (6% increase) due to increase in LV size. (The cavity dimensions were measured from the short-axis slices at the midventricular level in the initial and delayed images). The dilation was seen in patients with CAD but not in the normal subjects. These changes correlated with the extent and severity of the thallium perfusion abnormality. Thus, adenosine-induced coronary hyperemia may cause LV dilation and increased lung thallium uptake on the basis of subendocardial ischemia.

This study examined the effect of the level of exercise on the ability of thallium-201 imaging with single photon emission computed tomography (SPECT) to detect coronary artery disease. Patients in group 1 (n = 164) achieved adequate exercise end points, defined as positive exercise electrocardiograms or ≥85% of maximal predicted heart rate. Patients in group 2 (n = 108) had submaximal exercise.

This study compared the results of stress and rest single-photon emission computed tomography imaging of myocardial perfusion using technetium-99m isonitrile (RP-30A) with the results of stress and redistribution tomographic thallium imaging and the results of coronary arteriography in 39 patients, 11 without and 28 with coronary artery disease (CAD). Each patient underwent 2 exercise studies at identical workload, heart rate and double product. In a subset of 13 patients, concomitant evaluation of left ventricular (LV) function using first-pass radionuclide angiography with a multicrystal camera also was performed with bolus injections of isonitrile. Isonitrile had similar sensitivity (82 vs 82%, difference not significant), a slightly—but not significantly—higher specificity (100 vs 82%) and similar predictive accuracy (87 vs 82%) to thallium-201. The tracer uptake was assessed in 20 segments/study. There was concordance between the isonitrile and thallium-201 images in 723 of the 780 segments (93%) (kappa = 0.83 ± 0.02). In general, the isonitrile images were considered of better quality than the thallium-201 images. All 10 patients with CAD who underwent concomitant first-pass radionuclide angiography had either perfusion abnormalities or an abnormal ejection fraction response to exercise.

This study examined the merits of oral dipyridamole SPECT thallium-201 imaging in detecting CAD and multivessel CAD. The 65 patients included in this study (aged 62 +/- 11 years) were not candidates for exercise testing (for the usual reasons). Coronary arteriography revealed no significant CAD in 17 patients and greater than or equal to 50% narrowing of one or more vessels in 48 patients; 12 had one-vessel and 36 had multivessel CAD (high-risk group). Thallium-201 was injected intravenously 45 minutes after an oral dose of 375 mg of dipyridamole, and SPECT imaging was performed within 10 minutes and 4 hours after injection. There were no serious side effects; only six patients (8%) had ST segment depression and 18 patients (28%) had chest pain. The heart rate increased from 74 +/- 15 beats/min at rest to 84 +/- 14 beats/min at peak effect (p = 0.001); the systolic blood pressure did not change (130 +/- 18 and 128 +/- 20 mm Hg, respectively, p = NS). The thallium images were abnormal in 6 of 17 patients (35%) with no CAD, in 7 of 12 patients with one-vessel disease (58%), and in 34 of 36 patients with multivessel CAD (94%) (p = 0.001). Twenty-one of 25 patients (84%) with a perfusion abnormality in more than one vascular territory had multivessel CAD assessed by angiography. Thus oral dipyridamole SPECT thallium-201 imaging is a safe and inexpensive method for the detection of CAD in patients who are otherwise not candidates for exercise testing.(ABSTRACT TRUNCATED AT 250 WORDS)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTβ-Mercaptopropionic Acid as Colorimetric Reagent for Determination of CobaltEdward LyonsCite this: Anal. Chem. 1955, 27, 11, 1813Publication Date (Print):November 1, 1955Publication History Published online1 May 2002Published inissue 1 November 1955https://pubs.acs.org/doi/10.1021/ac60107a043https://doi.org/10.1021/ac60107a043research-articleACS PublicationsRequest reuse permissionsArticle Views41Altmetric-Citations2LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTTHIOGLYCOLIC ACID AS A COLOR TEST FOR IRONEdward LyonsCite this: J. Am. Chem. Soc. 1927, 49, 8, 1916–1920Publication Date (Print):August 1, 1927Publication History Published online1 May 2002Published inissue 1 August 1927https://pubs.acs.org/doi/10.1021/ja01407a010https://doi.org/10.1021/ja01407a010research-articleACS PublicationsRequest reuse permissionsArticle Views1250Altmetric-Citations36LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTMERCURY DERIVATIVES OF SOME IMIDESEdward LyonsCite this: J. Am. Chem. Soc. 1925, 47, 3, 830–833Publication Date (Print):March 1, 1925Publication History Published online1 May 2002Published inissue 1 March 1925https://doi.org/10.1021/ja01680a033RIGHTS & PERMISSIONSArticle Views28Altmetric-Citations2LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (283 KB) Get e-Alerts Get e-Alerts