Optimal timing of electrical cardioversion for acute decompensated heart failure caused by atrial arrhythmias: The earlier, the better?

The optimal timing for electrical cardioversion (ECV) in acute decompensated heart failure (ADHF) with atrial arrhythmias (AAs) is unknown. Here, we retrospectively evaluated the impact of ECV timing on SR maintenance, hospitalization duration, and cardiac function in patients with ADHF and AAs. Between October 2017 and December 2022, ECV was attempted in 73 patients (62 with atrial fibrillation and 11 with atrial flutter). Patients were classified into two groups based on the median number of days from hospitalization to ECV, as follows: early ECV (within 8 days, n = 38) and delayed ECV (9 days or more, n = 35). The primary endpoint was very short-term and short-term ECV failure (unsuccessful cardioversion and AA recurrence during hospitalization and within one month after ECV). Secondary endpoints included (1) acute ECV success, (2) ECVs attempted, (3) periprocedural complications, (4) transthoracic echocardiographic parameter changes within two months following successful ECV, and (5) hospitalization duration. ECV successfully restored SR in 62 of 73 patients (85%), with 10 (14%) requiring multiple ECV attempts (≥ 3), and periprocedural complications occurring in six (8%). Very short-term and short-term ECV failure occurred without between-group differences (51% vs. 63%, P = 0.87 and 61% vs. 72%, P = 0.43, respectively). Among 37 patients who underwent echocardiography before and after ECV success, the left ventricular ejection fraction (LVEF) significantly increased (38% [31-52] to 51% [39-63], P = 0.008) between admission and follow-up. Additionally, hospital stay length was shorter in the early ECV group than in the delayed ECV group (14 days [12-21] vs. 17 days [15-26], P < 0.001). Hospital stay duration was also correlated with days from admission to ECV (Spearman's ρ = 0.47, P < 0.001). In clinical practice, early ECV was associated with a shortened hospitalization duration and significantly increased LVEF in patients with ADHF and AAs.

Association between an early revascularization strategy and major cardiac events based on left ventricular dyssynchrony in patients at intermediate risk of major cardiac events using the J-ACCESS risk model.

Objective This retrospective study aimed to investigate the association between therapeutic strategies and the development of major cardiac events (MCEs) in intermediate-risk patients by using the J-ACCESS risk model in combination with the stress phase bandwidth (SPBW), an index of left ventricular dyssynchrony. Methods Patients were followed-up for three years to confirm their prognosis. Based on the estimated propensity scores, the patients who underwent revascularization within the first 60 days after SPECT and those who did not were matched 1:1 (n = 367 per group). The composite endpoint was the occurrence of MCEs, consisting of cardiac death, non-fatal myocardial infarction, and severe heart failure. SPBW was calculated by a phase analysis using the Heart Risk View-F software program, and the MCE rate was compared between the two groups by applying the normal value of SPBW (38°). Patients The study included 2,053 patients with either known or suspected CAD who underwent electrocardiogram-gated single-photon emission computed tomography myocardial perfusion imaging and were at intermediate risk of MCE according to the J-ACCESS risk model. Results During follow-up, 54 of the 734 patients (7.4%) experienced MCEs. The overall incidence of MCE in intermediate-risk patients was not significantly different between the two groups. However, the incidence of MCE in patients with an abnormal SPBW was significantly lower in those who underwent early revascularization (4.8% vs. 11.9%, P = 0.0407). Conclusion The combination of the J-ACCESS risk model and the SPBW is thus considered to be an optimal treatment strategy for patients at intermediate risk of MCE, and early revascularization may lead to an improved prognosis in intermediate-risk patients with an abnormal SPBW.

Optimization of 201Tl Dosage in a Simultaneous Acquisition Rest 99mTc/Stress 201Tl Dual-Isotope Myocardial Perfusion Single-Photon Emission Computed Tomography with Semiconductor Gamma Camera.

Background: The use of 201Tl in myocardial perfusion single-photon emission computed tomography (SPECT) is predominantly not recommended because of the higher radiation exposure of 201Tl compared to 99mTc agent. However, the advent of new gamma cameras with semiconductor detectors has made it possible to reduce the 201Tl dose and lower radiation exposure. In our hospital, the dose of 201Tl is adjusted according to the patient's body mass index (BMI), with 50 MBq for BMI<25 and 74 MBq for BMI≥25. The dose of 201Tl during simultaneous acquisition dual-isotope myocardial perfusion SPECT (MPS; stress 201Tl and rest 99mTc agent) exceeds 9 mSv/examination when 74 MBq of 201Tl is administered. In order to further reduce the radiation dose, optimization of the 201Tl dose was investigated. Methods: Two hundred and eighty consecutive patients who underwent stress MPS using simultaneous acquisition dual-isotope protocol (SDI protocol) for the estimation of ischemic heart disease were included. Patients with prior myocardial infarction were excluded. Correlations between BMI and acquisition time were determined in patients receiving 50 MBq (n=154) or 74 MBq (n=126) of 201Tl. In addition, linear regression analysis was used to determine the slope and intercept to derive a linear functional equation, and the theoretically optimal 201Tl dose was evaluated. Results: The correlation coefficient between BMI and acquisition time in the 201Tl 50 MBq group was 0.532 (P< 0.00001) and in the 201Tl 74 MBq group was 0.478 (P<0.00001), both showing a positive correlation. Linear regression analysis yielded two equations: y=0.52x-0.32 (201Tl 50 MBq group) and y=0.41x-0.69 (201Tl 74 MBq group). Linear function equation results indicated that patients with BMI between 25 and 30 could be examined within approximately 15 minutes with 50 MBq of 201Tl. Conclusion: Considering examination efficiency, a single acquisition time of less than 15 minutes is ideal. Theoretically, patients with BMI less than 30 could be examined within approximately 15 minutes with 50 MBq of 201Tl.

Hepatic steatosis evidenced by computed tomography in patients undergoing primary percutaneous coronary intervention for acute myocardial infarction.

BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) and acute myocardial infarction (AMI) have common pathological links. This study investigates the prognostic impact of NAFLD assessed as hepatic steatosis (HS) by computed tomography (CT) in AMI patients and explores the mechanistic role of NAFLD in cardiovascular (CV) events using coronary angioscopy (CAS). METHODS: We retrospectively examined 342 AMI patients who underwent CT followed by primary percutaneous coronary intervention (PCI) between January 2014 and December 2019. HS was defined as a hepatic to spleen attenuation ratio of <1.0 on CT scans. Major cardiac events (MCE) included cardiac death, non-fatal myocardial infarction, target-vessel revascularization, and target-lesion revascularization. RESULTS: HS was identified in 88 patients (26 %). Patients with HS were significantly younger, had a higher body mass index, and higher hemoglobin A1c, triglyceride, and malondialdehyde low-density lipoprotein levels (all p < 0.05). MCE occurred more frequently [27 (30.7 %) vs. 39 (15.4 %), p = 0.001] in the HS group than in the non-HS group. In the multivariate analysis, the presence of HS was an independent predictor of MCE after adjusting for metabolic risk factor and liver function markers. Among the 74 patients who underwent CAS for a median of 15 days after primary PCI, 51 (69 %) had intrastent thrombus, which was strongly associated with the presence of HS [18 (35 %) vs. 1 (4 %), p = 0.005]. CONCLUSIONS: AMI patients with NAFLD detected by CT often had CAS-derived intrastent thrombi and were at a high risk for CV events. Therefore, these patients should be carefully monitored.

Prognostic risk stratification based on left ventricular mechanical dyssynchrony in patients at low or intermediate risk of major cardiac events using the J-ACCESS risk model.

There have been no reports on prognostic prediction and risk stratification based on stress phase bandwidth (SPBW), or a left ventricular (LV) mechanical dyssynchrony index, in patients with known or suspected stable coronary artery disease (CAD) at low or intermediate risk of major cardiac events (MCEs) using the J-ACCESS risk model. We retrospectively investigated 4,996 consecutive patients with known or suspected CAD who underwent rest 201Tl and stress 99mTc-tetrofosmin electrocardiogram (ECG)-gated single-photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) and followed up for 3 years to confirm their prognosis. MCE risk over 3 years was estimated using an equation based on that used in the J-ACCESS study. The composite endpoint was the onset of MCEs consisting of cardiac death, non-fatal myocardial infarction (MI), and severe heart failure requiring hospitalization. SPBW was calculated by phase analysis with the Heart Risk View-F software and its normal upper limit was set to 38°. Based on the estimated 3-year incidence of MCEs obtained from the J-ACCESS risk model, 4,123 of the 4,996 consecutive patients were classified as low (n = 2,653) or intermediate risk (n = 1,470) and they were analyzed for follow-up. During the follow-up, 153 patients experienced MCEs: cardiac death (n = 38), non-fatal MI (n = 45), and severe heart failure (n = 70). The results of the multivariate analysis showed age, estimated glomerular filtration rate (eGFR), stress LV ejection fraction, and stress SPBW to be independent predictors of MCEs. The actual 3-year MCE rate in patients at intermediate risk was significantly higher than in those at low risk (6.7% vs. 2.1%, P < 0.0001). However, the actual 3-year MCE rate in patients with abnormal SPBW (> 38°) was 4.0% and 9.2% in low- and intermediate-risk patients, respectively, which corresponded to intermediate and high risk. Kaplan-Meier analysis also showed significant risk stratification by normal SPBW values for both low- and intermediate-risk patients. LV mechanical dyssynchrony assessed with ECG-gated SPECT MPI is useful for risk stratification of known or suspected stable CAD patients at low or intermediate risk of MCEs and may help identify higher risk patients who could not be identified as being at risk based on J-ACCESS risk assessment.

Optimal Protocol of Myocardial Perfusion Imaging for Reduction of Radiation Exposure.

The Japanese Circulation Society (JCS) 2021 guideline on radiation safety in cardiology was updated based on the eight best practices for myocardial perfusion single-photon emission computed tomography myocardial perfusion imaging (SPECT-MPI), which was determined by panels of international atomic energy agency (IAEA) nuclear cardiology protocols cross-sectional study (INCAPS). Although the guideline recommends to avoid too much 201Tl or 201Tl/99mTc dual-isotope protocol, the utilization rate of 201Tl for SPECT-MPI in Japan is considerably high compared to other countries. In Japan, protocols using 99mTc should be appropriately promoted based on the guideline to reduce radiation exposure in SPECT-MPI. Among the eight practices, stress-only imaging is considered to be a useful strategy that contributes to a significant reduction in radiation exposure, and hybrid assessment in combination with rest computed tomography (CT)-MPI is one of the practical application methods.

Relationship Among Coronary Artery Calcium Score, Myocardial Perfusion SPECT and Risk Stratification of Coronary Artery Disease.

Since Agatston et al. first reported quantification of the coronary artery calcification score (CACS) in 1990, discussion of its clinical significance and use in diagnostic management has continued. Recent papers have reported the relationship between CACS and myocardial perfusion single photon emission computed tomography (SPECT: MPS) and its combined diagnostic value. When interpreting CACS results, it should be noted that the frequency of significant ischemia detected by MPS, likelihood of coronary artery disease (CAD), and event rate gradually increased from mild to moderate CACS (1-400). At present, high CACS is considered to be moderately consistent with abnormal MPS, and abnormal CACS in normal MPS may contribute to CAD risk stratification. However, it should be noted that CACS=0 does not completely exclude CAD, which is particularly important when using CACS as a gatekeeper for MPS. Both stand-alone computed tomography (CT) scanner and hybrid SPECT-CT scanner are available for combined risk stratification of CACS and MPS in addition to improvement of image quality with attenuation correction.

Clinical Utility of a Slow 201Tl Washout Rate in the Detection of Multi-Vessel Coronary Artery Disease Using a Simultaneous Acquisition Rest 99 mTc/Stress 201Tl Protocol and a Semiconducting Gamma Camera.

BACKGROUND: The diagnostic accuracy of stress myocardial perfusion single-photon emission computed tomography (SPECT) to detect coronary artery disease (CAD) is reduced by the balanced reduction of myocardial perfusion in patients with multi-vessel or left main trunk CAD (multi-vessel group). This study investigated the diagnostic performance of a simultaneous acquisition rest 99 mTc/stress 201Tl dual-isotope protocol for myocardial perfusion SPECT (MPS) in a multi-vessel group by examining the assessment of a slow 201Tl washout rate (WR) finding in comparison to the accuracy of perfusion assessments.Methods and Results: This study enrolled 91 patients who had undergone angiography within 3 months after MPS. The diagnostic performances of perfusion assessments and a slow 201Tl WR parameter were compared using the area under the curve (AUC) in a multi-vessel group of patients with mild ischemia (2≤summed difference score [SDS]≤7). The AUC of a slow WR parameter was significantly larger compared with that for perfusion assessments, in patients with mild ischemia, (AUC, 0.736 vs. 0.504-0.558, P value: <0.01-0.05). CONCLUSIONS: Among patients with mild ischemia, a slow 201Tl WR parameter improved the detection of CAD in a multi-vessel group.

Prognostic value of the normalization of left ventricular mechanical dyssynchrony after revascularization in patients with coronary artery disease.

There are no reports indicating a prognostic difference based on normalization of left ventricular (LV) mechanical dyssynchrony after revascularization in patients with coronary artery disease (CAD). We retrospectively investigated 596 patients who underwent rest 201Tl and stress 99mTc-tetrofosmin electrocardiogram-gated single-photon emission computed tomography (SPECT) myocardial perfusion imaging. All patients had significant stenosis with ≥ 75% narrowing of the coronary arterial diameter detected by coronary angiography performed after confirmation of ≥ 5% ischemia by the SPECT. Patients underwent revascularization and thereafter were re-evaluated by the SPECT during a chronic phase, and followed-up to confirm their prognosis for ≥ 1 year. The composite endpoint was the onset of major cardiac events (MCEs) consisting of cardiac death, non-fatal myocardial infarction (MI), unstable angina pectoris (UAP), and severe heart failure requiring hospitalization. The stress phase bandwidth (SPBW) was calculated by phase analysis with the Heart Risk View-F software and its normal upper limit was set to 38°. During the follow-up, 64 patients experienced MCEs: Cardiac death (n = 11), non-fatal MI (n = 5), UAP (n = 26), and severe heart failure (n = 22). The results of the multivariate analysis showed the ∆summed difference score %, ∆stress LV ejection fraction, and stress SPBW after revascularization to be independent predictors of MCEs. Additionally, the results of the multivariate logistic regression analysis showed the summed rest score%, summed difference score%, stress LV ejection fraction, and perfusion defects in the left circumflex artery region before revascularization to be independent predictors for normalized SPBW after revascularization. The prognosis of patients who normalized SPBW after revascularization was similar to that of patients with a normal SPBW before revascularization, while patients who did not normalize after revascularization had the worst prognosis. In conclusion, normalization of LV dyssynchrony after revascularization assessed with nuclear cardiology may help predict future MCEs and thus a useful indicator for predicting improved prognosis in patients with CAD.

Association between the health insurance status and clinical outcomes among patients with acute heart failure in Japan.

The relationship between the socioeconomic status, including the health insurance status, and prognosis of heart failure (HF) has been recognized as an important concept for stratifying the risk in HF patients and is gaining increasing attention worldwide even in countries with a universal healthcare system. However, the impact of the Japanese health insurance status on outcomes among patients admitted for acute HF has not been fully clarified. We enrolled 771 patients admitted for acute HF between January 2018 and December 2019 and collected data on the in-hospital mortality, length of the hospital stay, and cardiac events, defined as cardiovascular death and readmission for HF within 1 year after discharge. Patients were divided into two groups according to their insurance status, i.e., public assistance (n = 87) vs. other insurance (n = 684). The public assistance group was significantly younger and had a higher rate of diabetes, smoking, ischemic and hypertensive heart disease, and low estimated glomerular filtration rate (all P < 0.05). Pharmacological/invasive heart failure therapy, in-hospital mortality, and the 90-day cardiac event rate after discharge did not differ between the groups. However, the public assistance group had a significantly higher 1-year cardiac event rate than the other insurance groups (P = 0.025). After adjusting for covariates, public assistance was independently associated with the 1-year cardiac event rate (HR: 2.15, 95% CI: 1.42-3.26, P < 0.001). Acute HF patients covered by public assistance received the same quality of medical care, including invasive therapy. As a result, no health disparities were found in terms of the in-hospital mortality and 90-day cardiac event rate, unlike overseas surveys. Nevertheless, HF patients with public assistance had a higher risk for the long-term prognosis than those with other insurance. Comprehensive HF management is required post-discharge.

Coronary artery calcium score: Current status of clinical application and how to handle the results.

The clinical significance of the coronary artery calcium score (CACS) has been discussed since Agatston et al. first reported its utility in 1990. CACS is less invasive and less expensive than contrast-enhanced coronary computed tomography (CT) angiography. However, to date, discussion continues on who is eligible for CACS assessment and how test results should be handled. Although the CACS cutoff value of 400 has been used in many previous studies for the detection of significant coronary artery disease (CAD) or cardiac event risk, other studies have reported that the frequency of significant ischemia, likelihood of CAD, and cardiac event rate are increasing, from mild to moderate CACS. The prognostic significance of patients with moderate CACS (1-400) is still uncertain, whereas in 2016, the Society of Cardiovascular CT and Society of Thoracic Radiology guidelines determined CACS ≥300 as moderate to severely increased risk. Another important value is CACS = 0. It is known that CACS = 0 decreases the likelihood of CAD after assessment of the pretest probability. In addition, management using statin therapy is a clinical situation that may benefit from CACS = 0. A previous study reported no significant difference in the prognosis between patients with and without statin therapy with CACS = 0. Some studies have reported the significance of the combination of CACS and noninvasive cardiac imaging, whereas CACS assessment is recommended for use in combination with risk assessment of pretest probability using clinical information including age, sex, and chest symptoms. While the utility of CACS in the management of CAD and primary prevention has been reconfirmed, the benefit of moderate values of CACS to predict prognosis with subsequent treatment and noninvasive cardiac imaging is still controversial.

Prognostic Significance of Left Ventricular Dyssynchrony Assessed with Nuclear Cardiology for the Prediction of Major Cardiac Events after Revascularization.

Objective This retrospective study was aimed at determining whether or not stress phase bandwidth (SPBW), a left ventricular (LV) mechanical dyssynchrony index, predicts major cardiac events (MCEs) and stratifies the risk of those in patients with coronary artery disease (CAD) who undergo revascularization. Methods Patients were followed up to confirm the prognosis for at least one year. The SPBW was calculated by a phase analysis using the Heart Risk View-F software program. The composite endpoint was the onset of MCEs, consisting of cardiac death, non-fatal myocardial infarction, unstable angina pectoris, and severe heart failure requiring hospitalization. Patients The study subjects were 332 patients with CAD who underwent coronary angiography and revascularization after confirming ≥5% ischemia detected by rest 201Tl and stress 99mTc-tetrofosmin electrocardiogram-gated single-photon emission computed tomography myocardial perfusion imaging. Results During the follow-up, 35 patients experienced MCEs of cardiac death (n=5), non-fatal myocardial infarction (n=3), unstable angina pectoris (n=11), and severe heart failure requiring hospitalization (n=16). A receiver operating characteristics analysis indicated that the optimal cut-off value of the SPBW was 52° for predicting MCEs, and the MCE rate was significantly higher in the patients with an SPBW >52° than in those with an SPBW ≤52°. Results of the multivariate analysis showed the SPBW and estimated glomerular filtration rate to be independent predictors for MCEs. In addition, the cut-off value of the SPBW significantly stratified the risk of MCEs according to the results of the Kaplan-Meier analysis. Conclusion Evaluating the SPBW before revascularization may help predict future MCEs in patients with CAD who intended to undergo treatment.

Comprehensive assessment of left atrial and ventricular remodeling in paroxysmal atrial fibrillation by the cardiovascular magnetic resonance myocardial extracellular volume fraction and feature tracking strain.

Atrial fibrillation (AF) is a progressive disease that starts with structural or functional changes in the left atrium and left ventricle, and evolves from paroxysmal toward sustained forms. Early detection of structural or functional changes in the left atrium and left ventricle in the paroxysmal stage could be useful for identifying a higher risk of progression to persistent AF and future cardio-cerebrovascular events. The aim of this study was to test the hypothesis that the feature tracking (FT) left atrial (LA) strain and left ventricular (LV) extracellular volume fraction (ECV) derived from cardiovascular magnetic resonance (CMR) could detect early changes in remodeling of the left atrium and ventricle in the paroxysmal AF (PAF) stage. The participants were comprised of 106 PAF patients (age, 66.1 ± 10.7 years; 66% male) who underwent clinical CMR before pulmonary vein isolation and 20 control subjects (age, 68.3 ± 8.6 years; 55% male). The CMR-FT LA strain/phasic function and LV-ECV were compared between the PAF and control groups. The total and passive LA empty fraction (LAEF) and LA strain (corresponding to LA reservoir and conduit function) were decreased in the PAF group as compared to the control group. However, active LAEF (corresponding to the LA booster pump function) did not differ significantly between the PAF group (33.9 ± 10.9%) and control group (37.9 ± 13.3%, p = 0.15), while the active LA strain (corresponding to the LA booster pump function) was significantly decreased in the PAF group (11.4 ± 4.3 vs. 15.2 ± 5.6%, p = 0.002). The LV-ECV was significantly greater in the PAF group (28.7 ± 2.8%) than control group (26.6 ± 2.0%, p = 0.002). In the PAF group, the LV-ECV correlated significantly with the E/e' and LA volume index. Regarding the LA strain, correlations were seen between the LV-ECV and both the reservoir function and conduit function. CMR-FT LA strain in combination with the LV-ECV in a single clinical study offers a potential imaging marker that identifies LA/LV remodeling including subtle LA booster pump dysfunction undetectable by the conventional booster pump LAEF in the PAF stage.

Incremental Predictive Value of Coronary Calcium Score in Risk Stratification of Coronary Revascularization in Patients With Normal or Mild Ischemia Using Nuclear Myocardial Perfusion Single Photon Emission Computed Tomography.

BACKGROUND: The incremental predictive value of the coronary artery calcium score (CACS) for risk stratification of coronary revascularization in patients with normal or mildly abnormal nuclear myocardial perfusion single photon emission computed tomography (MPS) scores is unknown.Methods and Results:We analyzed 528 patients in whom CACS was calculated and who underwent stress MPS within 3 months. Patients with known coronary artery disease, prior coronary revascularization, and those undergoing hemodialysis were excluded. Patients were followed-up with coronary revascularization based on the evidence of physiological ischemia defined by fractional flow reserve or severe coronary stenosis (≥90%). CACS was significantly associated with the summed stress score (SSS) from MPS assessment. Multivariate logistic regression analysis showed that high CACS (≥300; odds ratio [OR] 5.44, 95% confidence interval [CI] 2.28-13.0) and SSS (OR 1.29, 95% CI 1.18-1.40) were significant (P<0.001) predictors of future coronary revascularization. The log-rank test showed that high CACS stratified coronary revascularization in normal SSS (0-3; P<0.001) or mildly abnormal SSS (4-8; P=0.028) groups, whereas high CACS did not significantly stratify coronary revascularization in moderate to severe SSS (≥9; P=0.757). CONCLUSIONS: Risk stratification using CACS with a cut-off value 300 may have incremental predictive value for revascularization in patients with normal or mildly abnormal MPS.

High Wall Shear Stress Is Related to Atherosclerotic Plaque Rupture in the Aortic Arch of Patients with Cardiovascular Disease: A Study with Computational Fluid Dynamics Model and Non-Obstructive General Angioscopy.

AIMS: Wall shear stress (WSS) has been considered a major determinant of aortic atherosclerosis. Recently, non-obstructive general angioscopy (NOGA) was developed to visualize various atherosclerotic pathologies, including in vivo ruptured plaque (RP) in the aorta. However, the relationship between aortic RP and WSS distribution within the aortic wall is unclear. This study aimed to investigate the relationship between aortic NOGA-derived RP and the stereographic distribution of WSS by computational fluid dynamics (CFD) modeling using three-dimensional computed tomography (3D-CT) angiography. METHODS: We investigated 45 consecutive patients who underwent 3D-CT before coronary angiography and NOGA during coronary angiography. WSS in the aortic arch was measured by CFD analysis based on the finite element method using uniform inlet and outlet flow conditions. Aortic RP was detected by NOGA. RESULTS: Patients with a distinct RP showed a significantly higher maximum WSS value in the aortic arch than those without aortic RP (56.2±30.6 Pa vs 36.2±19.8 Pa, p=0.017), no significant difference was noted in the mean WSS between those with and without aortic RP. In a multivariate logistic regression analysis, the presence of a maximum WSS value more than a specific value was a significant predictor of aortic RP (odds ratio 7.21, 95% confidence interval 1.78-37.1,p=0.005). CONCLUSIONS: Aortic RP detected by NOGA was strongly associated with a higher maximum WSS in the aortic arch derived by CFD using 3D-CT. The maximum WSS value may have an important role in the underlying mechanism of not only aortic atherosclerosis, but also aortic RP.

Hybrid Assessment of Myocardial Ischemia Using Stress-Only Nuclear Myocardial Perfusion Imaging and Rest Computed Tomography Perfusion Imaging.

BACKGROUND: Sequential assessment using CT coronary angiography (coronary CT) and nuclear myocardial perfusion imaging (MPI) is considered an anatomical and functional evaluation of coronary artery disease (CAD). However, there can be unexpected radiation exposure. Hybrid MPI with stress-only nuclear MPI and rest CT-MPI using coronary CT may contribute to reducing the radiation dose in sequential assessment with nuclear MPI after coronary CT. We analyzed the diagnostic performance and total radiation dose of hybrid MPI for detection of significant CAD compared with sequential assessment using nuclear MPI after coronary CT.Methods and Results:The results for 101 patients who underwent coronary CT, nuclear MPI and invasive coronary angiography within 3 months of all imaging were analyzed. We calculated the summed difference score (SDS) from standard nuclear MPI and hybrid SDS from hybrid MPI, which revealed myocardial ischemia. The diagnostic performance of SDS and hybrid SDS for detecting significant CAD was analyzed using receiver-operating characteristic (ROC) curve analysis. We also compared the total radiation dose of both methods. The area under the ROC curve was not different between SDS and hybrid SDS (0.901 and 0.815, P=0.079). Total radiation dose of hybrid MPI was significantly lower than standard nuclear MPI with CT angiography (4.62 mSv vs. 9.72 mSv, P<0.0001). CONCLUSIONS: Hybrid MPI showed a precise diagnostic accuracy for significant CAD detection.

Prognostic Value of Left Ventricular Dyssynchrony Assessed with Nuclear Cardiology in Patients with Known or Suspected Stable Coronary Artery Disease with Preserved Left Ventricular Ejection Fraction.

Left ventricular (LV) mechanical dyssynchrony assessed with phase analysis of electrocardiogram (ECG) -gated single photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) is useful for predicting major cardiac events (MCEs) in patients with cardiac dysfunction. However, there is no report on its usefulness in Japanese patients with known or suspected stable coronary artery disease (CAD) with preserved LV ejection fraction (LVEF).We retrospectively investigated 3,374 consecutive patients with known or suspected CAD who underwent rest 201Tl and stress 99mTc-tetrofosmin ECG-gated SPECT MPI and had preserved LVEF (≥ 45%), and followed them up to confirm their prognosis for three years. The composite endpoint was the onset of MCEs consisting of cardiac death, non-fatal myocardial infarction (MI), unstable angina pectoris, and severe heart failure requiring hospitalization. LV mechanical dyssynchrony was evaluated with phase analysis with the Heart Risk View-F software to obtain the phase bandwidth and standard deviation.During the follow-up, 179 patients experienced MCEs: cardiac death (n = 42); non-fatal MI (n = 34); unstable angina pectoris (n = 54); and severe heart failure (n = 49). Results of the multivariate analysis showed age, a history of MI, diabetes mellitus, summed stress score, and stress phase bandwidth to be independent predictors for MCEs. In Kaplan-Meier analysis, prognoses were significantly stratified with the tertiles of stress phase bandwidth.LV mechanical dyssynchrony assessed with ECG-gated SPECT MPI is useful for predicting a prognosis and stratifying the risk of MCEs in Japanese patients with known or suspected stable CAD with preserved LVEF.

Prognostic Significance of the Residual SYNTAX Score and Ischemic Reduction Detected with Nuclear Cardiology for Prediction of Major Cardiac Events after Revascularization.

Objective There is no report on the risk stratification of major cardiac events (MCEs) with a combination of the Synergy between Percutaneous Coronary Intervention with Taxus and Cardiac Surgery (SYNTAX) score and ischemic reduction detected with rest 201Tl and stress 99mTc-tetrofosmin myocardial perfusion single-photon-emission computed tomography (SPECT) after revascularization in Japanese patients with coronary artery disease (CAD). Methods This was a retrospective study. The patients were followed up to confirm their prognosis for at least one year. Ischemia was evaluated based on the summed difference scores converted to the percentage of the total myocardium Safety Data Sheet (SDS%). The SYNTAX score and SDS% were calculated before and after revascularization. The endpoint was the occurrence of MCEs. Patients Study subjects were 293 patients who had a ≥75% stenotic lesion detected with coronary angiography following confirmation of ≥5% ischemia with SPECT, underwent revascularization, and thereafter received a re-evaluation with SPECT and coronary angiography. Results During the follow-up, 25 patients experienced MCEs of cardiac death (n=2), non-fatal myocardial infarction (n=3), and unstable angina pectoris (n=20). A receiver operating characteristic analysis indicated that the best cut-off values of the residual SYNTAX score and ΔSDS% were 12 and 5%, respectively, for the prediction of MCEs. The patients with a low residual SYNTAX score (<12) and high ΔSDS% (≥5%) had the best prognosis, while those with a high residual SYNTAX score (≥12) and low ΔSDS% (<5%) had the worst prognosis. Conclusion The combination of the residual SYNTAX score and ischemic reduction detected with nuclear cardiology is useful for predicting MCEs after revascularization.