Myocardial Blood Flow Quantification Using PET

Fifty (63%) patients between 1993 and 2005 were studied in an ECAT-951/31 PET system (Siemens/CTI, Knoxville, Tennessee, USA), as previously reported.12 (link) Twenty-three (29%) patients between 2005 and 2009 were studied in an ECAT Exact HR + PET camera (Siemens, Hoffman Estates, IL, USA), as previously reported.13 (link) Six (8%) patients between 2009 and 2015 were studied in a whole-body 64-slice PET/CT scanner Biograph True Point (Siemens Healthcare, Erlangen, Germany), as previously reported.14 (link) In brief, imaging acquisition started in resting conditions after a Nitrogen-13 ammonia i.v. injection. Following the part of the study at rest, pharmacological stress was induced with dipyridamole or adenosine. After the pharmacological stress, a second dose of Nitrogen-13 ammonia was injected i.v. and imaging acquisition was performed. Dynamic datasets were obtained at rest and under stress conditions. Dynamic rest and stress MBF data were expressed in ml/gr/min myocardial tissue. Myocardial blood flow quantifications were assessed by the Hutchins 2-tissue-compartment model.15 (link) MFR was quantified as the ratio of stress MBF to rest MBF. Abnormal MFR was considered < 2.0 and abnormal stress MBF was considered < 1.9 ml/gr/min.16 (link)