Impact of accelerated washout of Technetium-99m-sestamibi on exercise tolerance in patients with acute coronary syndrome: single-center experience

• Published in: Heart and vessels Vol. 37; no. 9; pp. 1506 - 1515
• Main Authors: Kato, Takashi, Noda, Toshiyuki, Tanaka, Shinichiro, Yagasaki, Hiroto, Iwama, Makoto, Tanihata, Shintaro, Arai, Masazumi, Minatoguchi, Shinya, Okura, Hiroyuki
• Format: Journal Article
• Language: English
• Published: Tokyo Springer Japan 01-09-2022; Springer Nature B.V
• Subjects: Acute coronary syndromes; Anaerobic threshold; Angina; Angina pectoris; Biomedical Engineering and Bioengineering; Cardiac Surgery; Cardiology; Computed tomography; Data analysis; Diabetes mellitus; Heart attacks; Injection; Mathematical analysis; Medical imaging; Medicine; Medicine & Public Health; Mitochondria; Multivariate analysis; Myocardial infarction; Myocardium; Original Article; Perfusion; Photon emission; Regression analysis; Single photon emission computed tomography; Technetium; Technetium isotopes; Tomography; Vascular Surgery; Myocardial perfusion imaging; Technetium-99m-sestamibi; Exercise tolerance; Acute coronary syndrome; Accelerated washout
• ISSN: 0910-8327; 1615-2573
• DOI: 10.1007/s00380-022-02058-3

Technetium-99m-sestamibi (
99m
Tc-sestamibi) single-photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) in patients with acute coronary syndrome (ACS) could be used to assess area-at-risks, as well as myocardial infarct or saved sizes. In patients with ACS, accelerated washout of
99m
Tc-sestamibi during early and delayed imaging in the acute phase may suggest mitochondrial dysfunction in the injured but salvaged myocardium. However, the link between
99m
Tc-sestamibi accelerated washout and exercise tolerance is unknown. The purpose of this study was to investigate a possible association between
99m
Tc-sestamibi accelerated washout and exercise tolerance in acute ACS patients as they progressed into the chronic phase. One hundred and sixty-five patients with ACS who underwent
99m
Tc-sestamibi SPECT MPI during the acute phase were recruited. On this basis, we calculated the total perfusion deficits (TPDs) for early (1 h after tracer injection) and delayed (4 h after tracer injection) images using automated quantification software. We then subtracted the early TPDs from the delayed TPDs to calculate the ΔTPD. We conducted a cardiopulmonary exercise test in acute and chronic phases. We divided two groups according to the median ΔTPD (the ΔTPD ≥ 4 group and the ΔTPD < 4 group) and compared anaerobic threshold (AT; ml/kg/min) between the groups. For anaerobic threshold (AT) improvement in data analysis, we employed multivariate logistic regression analysis. A total of 101 ST-segment elevation myocardial infarctions, 36 non-ST-elevation myocardial infarctions, and 28 unstable angina pectoris events were reported as ACS. From acute phase (10.8 ± 4.2 ml/kg/min) to chronic phase (11.9 ± 2.3 ml/kg/min), the AT in the ΔTPD ≥ 4 group was significantly increased (
p
< 0.0001). This trend was also seen in the ΔTPD < 4 group from acute (11.4 ± 1.8 ml/kg/min) to chronic phase (12.1 ± 2.2 ml/kg/min,
p
= 0.015). AT was lower in the ΔTPD ≥ 4 group in the acute phase (
p
= 0.027), but there was no difference in AT between the two groups in the chronic phase (
p
= 0.60). ΔTPD and the absence of diabetes were both independent predictors of AT improvement in multivariate logistic regression analysis. Receiver-operating characteristic curve analysis determined that ΔTPD = 6 was the best cut-off value, with 60.0% sensitivity and 71.4% specificity, respectively. The accelerated washout of
99m
Tc-sestamibi in patients with ACS during the acute phase could help to predict improvement in exercise tolerance in the chronic phase.