Reverse perfusion pattern in myocardial spect with 99mTc-sestaMIBI.

RATIONALE: The aim of our study was to investigate the myocardial perfusion deficit in rest images as compared to stress images in myocardial scintigraphy (MS). OBJECTIVES: The aim of this study is to investigate the reverse perfusion (RP) pattern in MS. METHODS AND RESULTS: 263 patients were enrolled in the study (72 females and 191 males; mean age 65.7 ± 9.5 years old). Mean body mass index (BMI) was of 27.6 ± 3.8 Kg/m2. 115 patients were positive for a previous history of myocardial infarction (MI). 142 patients reported a revascularization treatment (percutaneous transluminal coronary angioplasty, PTCA, cardiac stent placement, coronary artery bypass grafting, CABG). All the patients underwent MS following standard single day Stress/Rest protocol. In our series, 27 patients presented a RP pattern. We did not find statistically significant differences when considering age (p = 0.7988), sex (p = 0.0657), BMI (p = 0.8611), diabetes (p = 0.8259), dyslipidemia (p = 0.1464) or smoking status (p = 0.6829) in RP patients vs. non-RP patients. A history of MI is related to a RP pattern (p < 0.0001). A history of previous revascularization was not related with RP (p = 0.6868). DISCUSSION: The result of our study suggested that RP is probably related to artifacts of various origins. Further studies are necessary especially in microvascular dysfunction or a long history of disease.

Different patterns of cardiac sympathetic denervation in tremor-type compared to akinetic-rigid-type Parkinson's disease: molecular imaging with ¹²³I-MIBG.

The aim of this study was to evaluate the correlation between the clinical motor phenotypes of Parkinson's disease (PD) and ¹²³I-MIBG myocardial uptake. In total, 53 patients with PD [31 males and 22 females, mean age 62±10 years; 19 Hoehn & Yahr (H&Y) stage 1, 9 stage 1.5, 15 stage 2 and 10 at stage 3] were examined and subdivided into different clinical forms on the basis of dominance of resting tremor (n=19, TDT) and bradykinesia plus rigidity (n=34, ART). This status was correlated with the semi-quantitative analysis of ¹²³I-MIBG myocardial uptake. An age-matched control group of 18 patients was recruited (8 males and 10 females, mean age 62.4±16.3 years). ¹²³I-MIBG myocardial uptake significantly correlated with disease duration in early (r²=0.1894; P=0.0028) and delayed images (r²=0.1795; P=0.0037) in PD patients, while no correlation was found when considering age at examination, UPDRS III motor examination section score and H&Y score. PD patients showed a reduced ¹²³I-MIBG myocardial uptake compared to the control group in early (P=0.0026) and delayed images (P=0.0040), and ¹²³I-MIBG myocardial uptake was significantly lower in delayed images in TDT patients compared with ART patients (P=0.0167). A decrease was detected in the heart-to-mediastinum (H/M) ratio in delayed images compared to that of the early images in TDT patients (P=0.0040) and in the whole PD population (P=0.0012), while no differences were found in ART patients (P=0.1043). The results of the present study revealed that the cardiac sympathetic system is more severely impaired in TDT than in ART patients and ¹²³I-MIBG molecular imaging has the potential help in improving therapeutic planning in these patients.