A multicenter study of clinical predictors of positive pyrophosphate scintigraphy findings in the diagnosis of transthyretin amyloidosis

• Published in: International journal of cardiology Vol. 418; p. 132664
• Main Authors: Shingu, Manami, Fujimoto, Wataru, Onishi, Tetsuari, Kuragaichi, Takashi, Murai, Ryosuke, Matsuo, Koki, Inoue, Tomohiro, Takaya, Tomofumi, Matsumoto, Kensuke, Matsue, Yuya, Okuda, Masanori, Tanaka, Hidekazu
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.01.2025
• Subjects: 99mTc-labeled pyrophosphate scintigraphy; Clinical predictors; Wild-type transthyretin amyloidosis; Clinical predictors; 99mTc-labeled pyrophosphate scintigraphy; CI; ROC; IQR; HFpEF; IVSt; ATTR; AUC; Wild-type transthyretin amyloidosis; 99mTc-PYP; LVPWt; LVH; (99m)Tc-labeled pyrophosphate scintigraphy
• ISSN: 0167-5273; 1874-1754; 1874-1754
• DOI: 10.1016/j.ijcard.2024.132664

The prevalence of wild-type transthyretin (ATTR) amyloidosis is increasing with advancements in diagnostic techniques and growing awareness of the disease worldwide. 99mTc-labeled pyrophosphate (99mTc-PYP) scintigraphy exhibits high performance in diagnosing ATTR cardiac amyloidosis. This study aimed to validate the characteristics of patients with positive 99mTc-PYP scintigraphy results in a multicenter setting to provide more accurate case selection criteria. In total, 180 patients with suspected ATTR amyloidosis underwent 99mTc-PYP scintigraphy in participating institutions in Japan between January 2018 and July 2022. Of 135 patients included in the analysis, 62 were 99mTc-PYP-positive. Logistic regression analysis was performed, and the following five factors were adopted to create a scoring system, with each weighted according to its odds ratio value; 1 point was scored for the absence of hypertension, existence of peripheral entrapment neuropathy (carpal tunnel syndrome or spinal canal stenosis), conduction disturbance (the presence of QRS complex ≥120 ms, first-degree atrioventricular block, higher degree of atrioventricular block, or presence of pacemaker implantation), and left ventricular hypertrophy and 2 points for troponin I/T ≥ 0.06 ng/mL. 99mTc-PYP scintigraphy positivity rate in the 0-point group was 0 %, whereas that in the 6-point group was 100 %. The area under the curve of the criteria was 0.820 (95 % confidence interval, 0.752–0.888; P < 0.001). The combination of clinical information, which is easily available in local clinics, can provide accurate pretest prediction of positive 99mTc-PYP scintigraphy results. This will help clinicians to make an early diagnosis of ATTR amyloidosis. An illustration of the research overview. A scoring system of 0–6 points was created to predict positive pyrophosphate scintigraphy results to determine patients with a high pretest probability of positive results for the early diagnosis of ATTR amyloidosis. 99mTc-PYP, 99mTc-labeled pyrophosphate; ATTR, transthyretin; IVSt, interventricular septum thickness; LVPWt, left ventricular posterior wall thickness. [Display omitted] •99mTc-labeled pyrophosphate scintigraphy exhibits high performance in diagnosing wild-type transthyretin cardiac amyloidosis.•The combination of clinical information can provide accurate pretest prediction of positive pyrophosphate scintigraphy results.•The PATCH score, a scoring system combined with clinical information may help in early diagnosis of wild-type transthyretin amyloidosis.