Quantitative SPECT/CT parameters of myocardial 99mTechnetium-3,3-diphosphono-1,2-propanodicarboxylic acid (DPD) uptake in suspected cardiac transthyretin amyloidosis

Background: 99mTc-labelled bisphosphonates are used for imaging assessment of patients with transthyretin cardiac amyloidosis (ATTR). Present study evaluates whether quantitative SPECT/CT measurement of absolute myocardial 99mTc-labelled 3,3-diphosphono-1,2-propanodicarboxylic acid (Tc-DPD) uptake can diagnose patients with suspected ATTR. / Methods: Twenty-eight patients (25 male, age 80.03 ± 6.99 years) with suspected ATTR referred for Tc-DPD imaging had planar and SPECT/CT imaging of the chest. Three operators independently obtained Tc-DPD myocardial SUVmax and SUVmean above threshold (SMaT) (20, 40 and 60% of SUVmax), using a semi-automated threshold segmentation method. Results were compared to visual grading (0–3) of cardiac uptake. / Results: Twenty-two patients (78%) had cardiac uptake (2 grade 1, 15 grade 2, 5 grade 3). SUVmax and SMaT segmentation thresholds enabled separating grades 2/3 from 0/1 with excellent inter- and intra-reader correlation. Cut-off values 6.0, 2.5, 3 and 4 for SUVmax, SMaT20,40,60, respectively, separated between grades 2/3 and 0 /1 with PPV and NPV of 100%. SMaT20,40,60(cardiac)/SUVmean (liver) and SMaT20,40,60(cardiac)/SUVmean(liver/lung) separated grades 2 and 3. / Conclusion: Quantitative SPECT/CT parameters of cardiac Tc-DPD uptake are robust, enabling separation of patients with grades 2 and 3 cardiac uptake from grades 0 and 1. Larger patient cohorts will determine the incremental value of SPECT/CT quantification for ATTR management

Measuring the Effectiveness of Capital Investments

In a socialist society the effectiveness of outlays is determined by their influence on the productivity of social labor. This is recognized by all those who participate in the discussion of the problem of the effectiveness of capital investments. (>u>1>/u>) But having examined the logic of the arguments presented by many economists we discover that as soon as they deal with concrete methods of calculating the effectiveness of outlays the initial proportion on the effectiveness of outlays under socialism is either completely ignored in their arguments or is artificially tied to the proposed methods of calculation.

Capital Investments and Rates of Expanded Production

The Soviet Union's entry into the period of comprehensive construction of a communist society represents a new phase in the economic competition between socialism and capitalism. The decisive factor in this competition will be the high rates of growth of production in our country. All the major targets of the Seven-Year Plan are directed to the maximum accelerationof economic development, especially of the decisive branches 01 industry. "The fundamental problem in the coming seven-year period," according to the Resolutions of the 21st Party Congress, "is the problem of winning maximum time in the peaceful economic competition between socialist and capitalism."

The Logic of Planning

The author has a doctorate in economics, is affiliated with the Economics Institute of the USSR Academy of Sciences, and lives in Moscow. The article is published for discussion purposes.