{'fraction_non_alphanumeric': 0.031914893617021274, 'fraction_numerical': 0.031914893617021274, 'mean_word_length': 5.543478260869565, 'pattern_counts': {'":': 0, '<': 3, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Correlation between thallium-201 myocardial perfusion defects and the functional severity of coronary artery stenosis as assessed by pressure-derived myocardial fractional flow reserve.

Although a relationship between the coronary pressure-derived fractional flow reserve (FFR) and the presence of myocardial ischemia as demonstrated by radionuclide imaging has been reported in a select group of patients, it remains to be established whether this relation also holds true in actual clinical settings with a heterogeneous group of patients. Accordingly, 194 coronary vessels and their supply territories were evaluated in 165 consecutive patients with suspected or known coronary artery disease. An FFR <0.75, which is regarded as indicative of functionally important stenosis, showed a significant correlation with the redistribution of (201)Tl (p<0.0001), with a sensitivity of 79% and specificity of 73%. In 70 infarct-related coronary arteries, the sensitivity and specificity were 79% and 75%, respectively, whereas in the 124 remaining vessels that were not related to the myocardial infarct, the sensitivity and specificity were 80% and 72%, respectively. In addition, the FFR exhibited a significant inverse correlation with the (201)Tl reversibility score (r=-0.62; p<0.0001). These results suggest that the FFR has a significant relationship with scintigraphic evidence of myocardial ischemia and can be regarded as a marker of its presence or absence in patients in actual clinical settings.