SPECT and PET myocardial perfusion imaging in Austria, Germany, and Switzerland results of the first joint survey of 2021.

PURPOSE: This paper presents the results of the first joint survey on the use of SPECT and PET myocardial perfusion imaging (MPI) and cardiac amyloidosis imaging in Austria, Germany, and Switzerland of the year 2021. METHODS: A questionnaire was sent in 2022 to centres practicing nuclear medicine. RESULTS: Data from 14 Austrian (10,710 SPECT), 218 German (133,047 SPECT), and 16 Swiss centres (11,601 MPI (6,879 SPECT, 4722 PET)) were analysed. In Austria and Germany, the PET MPI numbers were close to zero and not considered. Official MPS numbers from 2015 to 2021 from Austria and Germany revealed a decline in Austria by about 40% in the pandemic years 2020 to 2021, but an increase in Germany by 9%. Ambulatory care cardiologists represented the major referral group (56-71%). Mostly, stress tests were performed pharmacologically (58-92%). Contrary to Germany, a 1-day protocol was predominant (58-97%) in Austria and Switzerland. The leading camera systems were SPECT-CT in Austria and Switzerland (57-79%) and multi-head systems in Germany (58%). Switzerland had the highest proportion of SPECT MPI with attenuation correction (84%), followed by Austria (43%), and Germany (33%). Electrocardiogram-gated SPECT MPI showed an overall high penetration of 87-99%. Scoring was most frequently applied in Germany (72%), followed by Austria (64%), and Switzerland (60%). Related to the population, the number of cardiac amyloidosis imaging was highest in Austria, followed by Switzerland and Germany. CONCLUSIONS: This first joint survey of 2021 shows considerable differences among the countries. The Swiss situation is outstanding due to the wide use of PET MPI. In terms of camera equipment, Switzerland is also leading, followed by Austria and Germany. Despite the differences in procedural issues, the results reveal an overall high standard of MPI imaging.

Myocardial perfusion SPECT in Germany from 2012 to 2021: insights into development and quality indicators.

PURPOSE: This paper summarises the results of 4 national surveys on the numbers, utilisation and technique of myocardial perfusion SPECT (MPS) from 2012 to 2021. METHODS: A one-page questionnaire for information on MPS in 2012, 2015, 2018 and 2021 was sent to German centres practising nuclear medicine. To check for representativeness, the numbers obtained were related to official annual data and furthermore to the numbers of invasive coronary angiography procedures (ICA). RESULTS: MPS examinations increased by > 40% from 2012 to 2021 and showed a centralisation with increasing MPS per centre. In 2020, a mild impact of the COVID-19 pandemic could be observed in the form of only a slight MPS increase, which was compensated in the following year. Outpatient care cardiologists represent the most important referrer (70%). Mostly, 2-day protocols were used. One-day protocols and stress-only protocols showed insignificant changes. The use of exercise stress decreased steadily. In 2021, exercise stress was replaced by pharmacological stress as the most frequent stress modality. Camera systems showed a shift to more SPECT-CT systems. The use of gated SPECT increased to almost 90%. Quantitative scoring showed an increasing acceptance. The ratio of invasive coronary angiographies (ICA) to MPS was between 3.9 and 4.5. A significant proportion of ICA in the context of CCS (chronic coronary syndrome) was performed without prior testing for ischaemia. CONCLUSION: The 2012 to 2021 MPS surveys reveal a continuously growing number of examinations with only a mild temporary effect of the COVID-19 pandemic and a centralisation with increasing numbers per centre. Performance and technical data reveal a high-grade adherence of MPS practice to the current ESC guideline. A large potential of non-invasive diagnostics remains for the future.

Correction to: The effect of beta blocker withdrawal on adenosine myocardial perfusion imaging.

Regrettably the original version of the above article contained errors in Table 2 and wrong values in the text. The corrected table is presented here and the values which have been corrected now appear in bold text. Page 1223 abstract Global MBF showed an increase from 180.2 ± 59.9 to 193.6 ± 60.8 mL minute/100 g (P = .002) after beta blocker withdrawal. Page 1225 Mean systolic and mean diastolic blood pressure during adenosine were nearly identical (P = .77 and P = .79) with and without beta blocker. Mean heart rate and mean RPP during adenosine significantly increased after beta blocker withdrawal by 15.2% ± 17% (P = .001) and 16.2% ± 23% (P = .004), respectively. Page 1226 The data are listed in Table 2, lower third. Global MBF showed a significant increase by 7.4% ± 10% (P = .002) after beta blocker withdrawal. The individual data are depicted in Figure 1. All but three patients had a lower global MBF without beta blocker than with. The segmental MBF values (Figure 2) demonstrated a strong correlation over the entire range of perfusion values. The average effect was a slight perfusion shift of about 1015 mL minute-1/100 g in the range of 100-300 mL minute-1/100 g. The mCR under adenosine declined by 8.1% ± 11% (P = .038) and the normalized RPP by 16.2% ± 21% (P = .004) after betablocker discontinuation. Table 2 Hemodynamic response under adenosine, perfusion, and left-ventricular function.

Use of myocardial perfusion imaging and estimation of associated radiation doses in Germany from 2005 to 2012.

PURPOSE: For several years the Working Group Cardiovascular Nuclear Medicine of the German Society of Nuclear Medicine has been performing a regular survey to obtain information on technique, utilization and development of myocardial perfusion scintigraphy (MPS). Currently, data of six surveys from 2005 to 2012 are available. The aim of this paper is to deliver a general and comprehensive overview of all surveys documenting the course of patient doses over time and the development of the method. METHODS: A one-page questionnaire with number of MPS patients, number of stress and rest MPS, referral structure and several technical issues was sent to all centres performing MPS in Germany and evaluated. With the data on protocol utilization, effective MPS patient doses were estimated. RESULTS: MPS per million population (pmp) varied between 2,380 and 2,770. In 2012, MPS pmp showed a slight increase for the first time. From 2005 to 2009 the angiography to MPS ratio increased from 3.4 to 4.4, and the revascularization to MPS ratio decreased from 0.66 to 0.53. In 2012, both indices demonstrated an opposite trend for the first time (4.1 and 0.55). A total of 108 centres participated in all surveys. They showed an increase in MPS patients of 4.0 % over the reporting period. In 2012, more than 50 % of the centres experienced no change or an increase in MPS numbers. The leading single competitor was MRI, followed by angiography and stress echocardiography. (201)Tl studies have decreased since 2005 from 20 to 5 %. (99m)Tc MPS studies showed a mild increase in 2-day protocols. In 2012, the average effective dose per patient was estimated at 7.4 mSv. Due to the decreasing use of (201)Tl, a mild decline over the observation period can be documented. Dynamic exercise stress was the most common stress test and adenosine the leading pharmacological stress agent, with a growing percentage. In 2012, the regadenoson percentage was 9 %. Gated single photon emission computed tomography (SPECT) noted an increasing acceptance with >70 % in 2012. The segmental scoring of perfusion studies had a low acceptance. Ambulatory care cardiologists represented the major referral group. CONCLUSION: Germany has a moderate to moderate-high MPS utilization rate. Nevertheless, coronary artery disease (CAD) diagnosis and disease management are dominated by angiography. The survey data reveal a positive trend in MPS and a decrease in average patient dose reflecting good practice with guideline adherence, the implementation of technical improvements and success in training.

The effect of beta blocker withdrawal on adenosine myocardial perfusion imaging.

BACKGROUND: The effect of beta blockers on myocardial blood flow (MBF) under vasodilators has been studied in several SPECT and PET myocardial perfusion imaging (MPI) studies with divergent results. The present study evaluated the effect of a beta blocker withdrawal on quantitative adenosine MBF and on MPI results. METHODS: Twenty patients with beta blockers and CAD history were studied with quantitative adenosine N-13 ammonia PET. The first study was performed under complete medication and the second after beta blocker withdrawal. The PET studies were independently read with respect to MPI result and clinical decision making. RESULTS: Global MBF showed an increase from 180.2 ± 59.9 to 193.6 ± 60.8 mL·minute(-1)/100 g (P = .02) after beta blocker withdrawal. The segmental perfusion values were closely correlated (R(2) = 0.82) over the entire range of perfusion values. An essentially different interpretation after beta blocker discontinuation was found in two cases (10%). CONCLUSION: A beta blocker withdrawal induces an increase in adenosine MBF. In the majority of cases, MPI interpretation and decision making are independent of beta blocker intake. If a temporary beta blocker withdrawal before MPI is not possible or was not realized by the patient, it is appropriate to perform adenosine stress testing without loss of the essential MPI result.

Erdheim-Chester disease in a female cardiac surgery patient.

We report a case of Erdheim-Chester disease (ECD) with isolated cardiac involvement in a 74-year-old female patient. The patient initially presented with superior vena cava syndrome and PET-CT imaging demonstrating an obstructing hypermetabolic lesion in the right atrium, and a distinct nonobstructing hypermetabolic lesion in the left atrium, expected to be malignant. There was no evidence of extracardiac disease. At surgical exploration, consistent with malignancy, the right atrial tumor was found to have grown into the pericardium and was resected to address symptoms and for histological diagnosis which revealed ECD on immunohistochemistry. We conclude that isolated cardiac ECD should be included in the surgical strategy for cardiac tumors showing infiltrative growth.

Diffusion-weighted magnetic resonance imaging for the detection of ischemic brain lesions in coronary artery bypass graft surgery: relation to extracorporeal circulation and heparinization.

AIM: Cognitive decline is a well recognized complication after on-pump coronary artery bypass graft (CABG) surgery. We investigated whether the design of extracorporeal circulation (ECC) and the extent of perioperative heparinization have an impact on neurological dysfunction. METHODS: Sixty-three CABG surgery patients were randomly perfused with an uncoated ECC-set (group A) or with two different heparin-coated ECC-sets (groups B and C). In groups A and B, systemic heparin was given in doses of 400 IU/kg body weight, whereas group C received 150 IU/kg body weight. ECC sets in group C included a diagonal pump and low priming as opposed to roller pumps in groups A and B. Furthermore, in group C blood contact to surfaces other than endothelium and heparin coated material was eliminated. Brain lesions were detected by diffusion-weighted magnetic resonance imaging (DWI). Neurological complications were assessed clinically until discharge (manifest motoric, sensitive or cognitive disturbance). Biochemical coagulation and inflammation parameters were measured pre-, peri-, and postoperatively. RESULTS: No major neurological events were observed in either group until discharge. DWIs showed 61 new lesions in 19 of 45 patients who terminated all MRI study procedures. Number and volume of the lesions did not differ between groups (P>0.05). Biochemical and inflammatory parameters showed the expected time courses and variations between groups. CONCLUSION: Ischemic brain lesions are frequently observed in CABG surgery patients but are neither associated with clinically relevant neurological complications nor with ECC set-up and intraoperative heparin dosage. DWI may help in the development of new surgical strategies to reduce postoperative brain damage.

[Myocardial perfusion scintigraphy 2008 in Germany - results of the fourth query]. / Myokard-Perfusions-Szintigraphie 2008 in Deutschland - Ergebnisse der vierten Erhebung.

AIM: The working group Cardiovascular Nuclear Medicine of the German Society of Nuclear Medicine in cooperation with the working group Nuclear Cardiology of the German Cardiac Society herewith present the results of the 4th survey on myocardial perfusion scintigraphy (MPS) of the year 2008. METHOD: 310 questionnaires (191 private practices (PP), 93 hospitals (HO), 31 university hospitals (UH)) were evaluated. RESULTS: MPS of 98947 patients were reported. 15% of them were younger than 50 y, 57% between 50 and 70 y and 28% older than 70 y. 88% [2007: 83%] of all were studied with Tc-99m perfusion tracers. The patient radiation exposure of a stress and rest protocol considering German standard recommended doses was 8.5 mSv, of a stress-only protocol 1.9 mSv. 77% [2007: 76%] of the MPS were performed in PP, 15% [2007: 15%] in HO and 8% [2007: 9%] in UH. From 2005 to 2008 there was a mild increase in the MPS numbers by 1.2% (PP +7.1%, HO -5.5%, UH -31.4%). The type of stress was pharmacological in 30% [2007: 27%]; 68% adenosine (of these 22% with exercise), 29% dipyridamole (of these 64% with exercise), and <1% dobutamine. Gated SPECT was performed in 46% [2007: 47%] of all rest and in 42% [2007: 44%] of all stress MPS. 62% [2007: 61%] of all institutions did not use perfusion scores. CONCLUSION: The MPS numbers from 2005 to 2008 in Germany can be regarded as stable. However, there are considerable shifts from HO and UH to PP. The well known potential of MPS considering risk stratification and functional analysis has not been tapped so far. Both gated SPECT and a quantitative perfusion analysis should be performed routinely in every patient.

[Myocardial perfusion scintigraphy 2007 in Germany--results of the query and current status]. / Myokardperfusionsszintigraphie 2007 in Deutschland--Ergebnisse der Erhebung und Standortbestimmung.

AIM: This third survey of the working group Cardiovascular Nuclear Medicine of the German Society of Nuclear Medicine in cooperation with the working group Nuclear Cardiology of the German Cardiac Society was to deliver information on the procedures and in particular on the development of myocardial perfusion scintigraphy (MPS) from 2005 to 2007. METHOD: 370 questionnaires (222 private practices (PP), 117 hospitals (HO), 31 university hospitals (UH)) were evaluated. RESULTS: MPS of 114,374 patients were reported, 83% were investigated with 99mTc-perfusion tracers. 76% [2006=74%] were performed in PP, 15% [2006=17%] in HO and 9% [2006=9%] in UH. Diabetics represented 21% of all MPS patients in 2007. Data of 215 institutions which participated all from 2005 to 2007 showed an increase in MPS of 2.3% (PP +6.8%, HO -4.5%, UH -18.2%). The type of stress was pharmacological in 27% [2006 = 27%]; 67% adenosine (of these 25% with exercise), 31% dipyridamole (of these 55% with exercise), and 2% dobutamine. Gated SPECT was performed in 47% [2006 = 42%] of all rest and in 44% [2006 = 39%] of all stress MPS. 61% [2006 = 83%] of all institutions did not apply perfusion scores. 20% [2006 = 24%] of the institutions reported changes in the use of MPS by competing methods. CONCLUSION: There is a small increase of MPS between 2005 and 2007 despite competing methods. Gated SPECT has experienced more acceptance, but is still underrepresented. As compared to the European average and general standards of MPS a considerable backlog accounts to pharmacological stress tests, gated SPECT and perfusion scores.

Myocardial sympathetic innervation in diabetic patients with symptomatic coronary artery disease.

AIM: In non-diabetic patients, sympathetic innervation can be preserved even if there is major impairment of myocardial blood supply. Matters may be more complex in diabetic patients because denervation can be caused by cardiac autonomic neuropathy (CAN) or by ischemic injury. Our aim was to determine whether restrictions in myocardial blood supply have a pronounced influence on sympathetic innervation in diabetics and if this effect can be differentiated from CAN. PATIENTS, METHODS: We analyzed 20 diabetics with advanced coronary artery disease (CAD) and without known CAN. We determined quantitative myocardial blood flow using (13)N-ammonia-PET, myocardial viability with (18)F-FDG, and cardiac innervation with (11)C-HED. We investigated the relationship between regional HED retention, blood flow, and coronary flow reserve (CFR). Attenuated heart rate response to adenosine was taken as indicator for CAN (HR ratio). RESULTS: There was minor correlation of segmental stress flow and HED retention (r(2)=0.063, p<0.0001). Correlation improved when stress flow as well as HED retention were normalized to the individual maximum (r(2)=0.162, p<0.0001). In nine patients, a HR ratio <1.2 implicated subclinical CAN. Duration of diabetic disease or glycaemic control (HbA1c) did not correlate with mean HED retention in the viable segments, but with its variation coefficient. CONCLUSIONS: As in non-diabetic patients, a slight correlation exists between CFR and sympathetic innervation. The sensitivity of sympathetic nerves to reductions in CFR does not seem to be increased as compared to the results reported for non-diabetics. Besides impaired blood supply, long duration of diabetic disease and bad glycaemic control also seem to impair sympathetic innervation provoking higher heterogeneity.

[Myocardial perfusion scintigraphy 2006 in Germany. Results of the query and current status]. / Myokardperfusionsszintigraphie 2006 in Deutschland Ergebnisse der Erhebung und Standortbestimmung.

AIM: This second survey was to deliver further information on myocardial perfusion scintigraphy (MPS) in Germany in 2006. METHOD: 351 questionnaires were evaluated: 207 private practices (PP), 117 hospitals (HO), 27 from university hospitals (UH). RESULTS: MPS of 106 331 patients were reported, 85% were investigated with (99m)Tc-perfusion tracers. 74% [2005 = 72%] were performed in PP, 17% [2005 = 15%] in HO and 9% [2005 = 13%] in UH. PP, which participated in 2005 and 2006, demonstrated an increase by 3,9% (HO 0%, UH - 13,0%). The type of stress was pharmacological in 27% [2005 = 22%]; 54% adenosine (of these 29% with exercise), 37% dipyridamole (of these 56% with exercise), and 9% dobutamine. Gated SPECT was performed in 42% [2005 = 36%] of all rest- and in 39% [2005 = 32%] of all stress MPS. An attenuation correction was used by 69 [2005 = 78] institutions. 40% of all MPS were performed in patients suspected to have CAD. 24% of all institutions reported changes in the use of MPS by competing methods. CONCLUSION: There is a small increase of MPS between 2005 and 2006 despite competing methods. Gated SPECT has experienced more acceptance. Suspicion of CAD is an important indication of MPS. In order to tap the full potential of MPS a gated SPECT should be performed routinely.

[Lutetium-177-PSMA radioligand therapy : Consensus within the framework of GKV-funded care between the university hospitals in Aachen, Bonn, Düsseldorf, Essen, and Cologne and the MDK Nordrhein]. / Lutetium-177-PSMA-Radioligandentherapie : Konsensus im Rahmen der GKV-finanzierten Versorgung zwischen den Hochschulkliniken in Aachen, Bonn, Düsseldorf, Essen und Köln und dem MDK Nordrhein.

In the last 3 years, Lutetium-177 prostate-specific membrane antigen radioligand therapy (Lu-177-PSMA-RLT) has received increasing attention in nuclear medicine as a new form of treatment for castration-resistant metastatic prostate cancer. This therapy combines the radionuclide Lutetium-177, which has been therapeutically used in nuclear medicine for many years, with a molecular target of the transmembrane prostate-specific membrane antigen expressed by prostate cancer cells. Since there are no prospective randomized studies on Lu-177-PSMA-RLT and the question of reimbursement has repeatedly been the subject of review by the MDK Nordrhein (Medischenische Dienst der Krankenversicherung), there was a desire because of the increasing number of patients being treated to clarify under which circumstances Lu-177-PSMA-RLT can be reimbursed by German statutory health insurance. The goals of this article are to help treating physicians understand how this new therapy option works, to integrate it in the overall therapy concept for castration-resistant metastatic prostate cancer, and, above all, to use Lu-177-PSMA-RLT-based on the current data-at the right place in the therapy sequence of castration-resistant metastatic prostate cancer.

Insulin resistance in liver cirrhosis. Positron-emission tomography scan analysis of skeletal muscle glucose metabolism.

BACKGROUND: Insulin resistance and glucose intolerance are a major feature of patients with liver cirrhosis. However, site and mechanism of insulin resistance in cirrhosis are unknown. We investigated insulin-induced glucose metabolism of skeletal muscle by positron-emission tomography to identify possible defects of muscle glucose metabolism in these patients. METHODS: Whole body glucose disposal and oxidation were determined by the combined use of the euglycemic-hyperinsulinemic clamp technique (insulin infusion rate: 1 mU/kg body wt per min) and indirect calorimetry in seven patients with biopsy-proven liver cirrhosis (Child: 1A, 5B, and 1C) and five healthy volunteers. Muscle glucose uptake of the thighs was measured simultaneously by dynamic [18F]fluorodeoxyglucose positron-emission tomography scan. RESULTS: Both whole body and nonoxidative glucose disposal were significantly reduced in patients with liver cirrhosis (by 48%, P < 0.001, and 79%, P < 0.0001, respectively), whereas glucose oxidation and the increase in plasma lactate were normal. Concomitantly, skeletal muscle glucose uptake was reduced by 69% in liver cirrhosis (P < 0.003) and explained 55 or 92% of whole body glucose disposal in cirrhotics and controls, respectively. Analysis of kinetic constants using a three-compartment model further indicated reduced glucose transport (P < 0.05) but unchanged phosphorylation of glucose in patients with liver cirrhosis. CONCLUSIONS: Patients with liver cirrhosis show significant insulin resistance that is characterized by both decreased glucose transport and decreased nonoxidative glucose metabolism in skeletal muscle.

[Myocardial perfusion scintigraphy in Germany. Results of the 2005 query and current status]. / Myokardszintigraphie in Deutschland. Ergebnisse der Erhebung 2005 und Standortbestimmung.

UNLABELLED: The working group Cardiovascular Nuclear Medicine of the German Society of Nuclear Medicine (DGN), in cooperation with the working group Nuclear Cardiology of the German Cardiac Society (DGK), decided to conduct a national survey on myocardial perfusion scintigraphy (MPS). METHOD: A questionnaire to evaluate MPS for the year 2005 was sent. RESULTS: 346 completed questionnaires had been returned (213 private practices, 99 hospitals and 33 university hospitals). MPS of 112 707 patients were reported with 110 747 stress and 95 878 rest studies. The majority (>75%) was performed with (99m)Tc-MIBI or tetrofosmin. (201)Tl stress-redistribution was used in 22 637 patients (20%). The types of stress were exercise in 78%, vasodilation with adenosine or dipyridamol in 21% and dobutamine in 1%. 99.97% of all MPS were SPECT studies. Gated SPECT was performed in 36% of the stress and in 32% of the rest studies. An attenuation correction was used in 21%. 29 institutions (8%) performed gated SPECT (stress and rest) and attenuation correction. 47% of all MPS were requested by ambulatory care cardiologists, 17% by internists, 12% by primary care physicians, 21% by hospital departments and 2% by others. CONCLUSION: In Germany, MPS is predominantly performed with (99m)Tc-perfusion agents. The common type of stress is ergometry. Gated SPECT and attenuation correction do not yet represent standards of MPS practice in Germany, which indicates some potential of optimization.

Cardiac re-synchronization therapy: effects on myocardial perfusion at rest, after vasodilation and oxygen consumption.

AIM: Cardiac resynchronization therapy (CRT) has been shown to improve haemodynamics and clinical symptoms in heart failure patients. The present study evaluated the effects of a 4-month CRT on myocardial blood flow (MBF) at rest, after vasodilation and on myocardial oxygen consumption (MVO(2)). PATIENTS, METHODS: We studied 16 patients with idiopathic dilated cardiomyopathy prior to and during CRT performed as biventricular pacing. Resting MBF and MVO(2) were determined from an (11)C-acetate PET study and vasodilator MBF from a (13)N-ammonia study. RESULTS: MBF at rest (0.55 +/- 0.10 ml/min/g), after vasodilation (1.20 +/- 0.45 ml/min/g), and MVO2 (0.082 +/- 0.014/min) did not change by mid-term CRT at a global level (0.57 +/- 0.11 ml/min/g; 1.32 +/- 0.49 ml/min/g; 0.085 +/- 0.018/min), whereas the rate pressure product (RPP) normalised MVO(2) decreased from 0.104 +/- 0.024 to 0.086 +/- 0.018/min (p = 0.02). At baseline, the regional analysis revealed significantly higher values for all parameters in the lateral wall than for those in the other walls. Under CRT the regional differences between the resting parameters equalized and all parameters showed significant lower coefficients of variation. CONCLUSION: Effects of mid-term CRT on resting MBF, vasodilator MBF and MVO(2) occur at a regional level. The resynchronization is associated with a more homogenous distribution pattern of these parameters among the myocardial walls. Substantial alterations to global MBF at rest, after vasodilation or to MVO(2) are not detectable. Regarding the RPP normalised MVO(2), there is evidence of improved ventricular efficiency through CRT.

Synthesis and evaluation of fluorine-18 labelled compounds for imaging of bacterial infections with pet.

Syntheses of no carrier added (n.c.a.) 6-fluoro-1,4-dihydro-1-cyclopropyl-4-oxo-7-[4-[18F]fluoro-phenacyl-1-piperacinyl]-chinolincarboxylic acid ([18F]COPCA) and n.c.a. 4-[18F]fluoro-benzoyl-ubiquicidin 29-41 ([18F]UBI 29-41) are described. [18F]COPCA was synthesised within 120 min with a radiochemical yield of 9-12%. [18F]UBI 29-41 was synthesised within 150 min with a radiochemical yield of 15-20%. Both compounds had a specific activity of more than 35 GBq/micromol. The biological activity was verified by measuring its binding to Staphylococcus aureus bacteria. Specific binding was found for [18F]UBI 29-41 (12-17%), whereas no specific binding for [18F]COPCA was found.

The effect of beta blocker withdrawal on myocardial SPECT modeled from adenosine 13N-ammonia PET.

AIM: The effect of beta blockers (BB) on myocardial imaging has been studied in several SPECT and PET studies with divergent results concerning perfusion and impact on diagnostic accuracy. The present study evaluated the effect of BB withdrawal on virtual SPECT studies modeled from quantitative PET perfusion scans. PATIENTS, METHODS: Data from 20 CAD patients scheduled for adenosine 13N-ammonia imaging with and without BB were considered. Modeling the uptake characteristics of 99mTc-MIBI, all parametric stress PET polarmaps were transferred to virtual 20-segment SPECT polarmaps. The SPECT studies were categorized with a 5-point score and read to assess the effect of the BB withdrawal on scan result and interpretation. RESULTS: The SPECT analysis revealed a mean score of 6.0 ± 4.7 with, and of 5.9 ± 4.5 without BB (p = 0.84). In 260 (74.9%) segments the scores were equal in both conditions. Without BB a downstaging was recorded in 44 segments (12.7%), an upstaging in 43 segments (12.4%). An essentially different interpretation (shift from medical therapy recommendation to angiography) was recorded in one patient. In six cases the interpretation differed mildly. CONCLUSION: In the majority of patients studied, scan results and interpretation remain unchanged after discontinuation of the BB. Nevertheless, the segmental scan results are not uniformly affected. The recommendation to stop BBs prior to stress testing in order to ensure the highest MBF remains advisable. If temporary BB withdrawal is unfeasible due to contraindications, a tight clinical schedule, or because a patient forgot to withhold the BB, it is appropriate to perform adenosine stress testing according to the results of this study.

The role of FDG-PET-CT in pediatric cardiac patients and patients with congenital heart defects.

AIM: Medical imaging by using FDG-PET/CT (PET-CT) can detect, confirm or eliminate with high sensitivity areas of suspected infections in case of persistent fever of unknown origin in combination with other bacteriological examinations. The aim of this study was to assess the potential role of PET-CT in detecting or excluding infections or other inflammatory processes in patients with congenital heart defects (CHD). In addition we wanted to evaluate the practical impact of PET-CT on the subsequent clinical management. METHODS: In this retrospective study we analyzed the data of all CHD patients who underwent PET-CT over a 5year period in our institution. The results were then evaluated with regard to the potential impact on clinical decision making. RESULTS: Between 2010 and 2015 PET-CT was performed in 30 patients. The mean age was 26years (SD 15years, range 1 to 66years). The diagnoses covered a large field of CHD. 11 patients (4/11 with assist device) were assessed before heart transplantation; suspected malignancies or infections were excluded and transplant listing was possible. In another 5/6 patients suspected assist device infection could be confirmed with PET/CT. Endocarditis was suspected in 13 patients, 2 of whom underwent previous MRI without confirmation and ECHO was inconclusive. Endocarditis was finally excluded in 5/13 patients but confirmed in 8/13 patients by PET-CT. CONCLUSION: In this study we could show a high sensitivity of PET-CT for specific localization of infections and with high impact on subsequent therapy. Based on this results clinical management could be targeted and adapted. We could demonstrate that PET-CT has a high impact on the subsequent clinical therapy.

Cardiac shock wave therapy and myocardial perfusion in severe coronary artery disease.

BACKGROUND: Ultrasound guided cardiac shock wave therapy (CSWT) is a noninvasive therapeutic option in the treatment of chronic-refractory angina. Clinical trials have shown that CSWT reduces angina symptoms, improves regional systolic function, LV ejection fraction, myocardial perfusion and quality of life parameters. Absolute measurements of myocardial perfusion before and after CSWT have not been performed so far. METHODS AND RESULTS: We studied a total of 21 CCS III patients with history of CAD and multiple interventions who suffered from disabling angina despite individually optimized medical therapy. An N-13 NH3 PET perfusion scan under adenosine was performed before and after CSWT treatment. CSWT was well tolerated in all patients. Absolute perfusion under adenosine of the global left-ventricular myocardium did not change under therapy or minimal coronary resistance. The treated segments, however, showed in terms of both perfusion and resistance a mild but significant improvement, by 11 and 15 %, respectively, whereas no change could be observed in the remote segments. Considering a threshold of increased perfusion of 5 %, 10 (77 %) out of 13 patients with a better target perfusion improved in their CCS class, whereas 3 (43 %) out of 7 patients without improved target perfusion improved in their CCS class too. CONCLUSION: Standard CSWT has the potential to improve myocardial perfusion of the therapy zone and clinical CAD symptomatology without affecting global myocardial perfusion. As a noninvasive and well tolerated therapeutic option, these data suggest the use of CSWT in patients with end-stage CAD.