Gated SPECT Myocardial Perfusion Research Articles

Diagnosis, performance and added value of assessing ventricular dyssynchrony by phase analysis in patients with three-vessel disease: A single-center cross-sectional study in Mexico

BackgroundThree-vessel disease (3VD) is a cardiovascular disorder that affects the three main coronary arteries. Gated myocardial perfusion SPECT (GMPS) evaluates ventricular function, synchrony, and myocardial perfusion. However, the diagnostic performance of GMPS parameters to assess 3VD has not been fully explored. AimsTo assess the univariate performance capacity of GMPS parameters, and to evaluate whether phase parameters could provide additional predictive value for the detection of patients with 3VD compared to control subjects. MethodsWe designed paired retrospective samples of GMPS images of patients with 3VD (stenosis > 70% of left anterior descending, right coronary, and circumflex coronary arteries) and without 3VD. A GMPS in rest-stress protocol was performed using 99mTc-Sestamibi and thallium and analyzed with the 3D method. Area under the receiver-operating characteristic curves (AUROC), decision curve analyses and diagnostic test performance were obtained for univariable analyses and stepwise binomial logistic regression for multivariable performance. Results474 Patients were included: 237 with 3VD (84% males, mean age 61.7 ± 9.9 years) and 237 with normal GMPS (51% women, mean age 63.8 ± 10.6 years). The highest AUROC for perfusion parameters were recorded for SSS, SRS and TID. For dyssynchrony parameters, both entropy and bandwidth in rest and stress phases displayed the highest AUROC and diagnostic capacity to detect 3VD. A multivariate model with SRS ≥ 4, SDS ≥ 2, TID > 1.19 and sBW ≥ 48° displayed the highest diagnostic capacity (0.923 [95% CI 0.897-0.923]) to detect 3VD. ConclusionPerfusion and dyssynchrony were the parameters which were most able to discriminate patients with 3VD from those who did not have CAD.

Association between glycated hemoglobin (HbA1c) level and cardiac perfusion and function on gated myocardial perfusion SPECT

BackgroundGlycated hemoglobin (HbA1c) is a recognized biomarker that keeps track of long-term blood sugar levels. Some studies revealed that even a modest elevation of blood glucose levels was linked to a higher chance of developing CAD. In this study we aim to test the impact of HbA1c level on perfusion and function metrics derived from myocardial perfusion gated SPECT (MPGS) imaging.ResultsTwo hundred patients were recruited in this study (mean age 58.21 ± 11.53 years; 51% males), of whom 132 patients (66%) were diabetic. Diabetic patients had a higher mean HbA1c of 7.92 ± 1.99 versus 6.05 ± 0.99 in non-diabetics (p < 0.001). HbA1c% was negatively correlated to LVEF% (r = − 0.262; p < 0.001) and HDL (r = − 0.316; p < 0.001), though, it was positively correlated to ESV (r = 0.221; p = 0.002) and EDV (r = 0.291; p < 0.001). Patients with HbA1c% > 6.5 compared to ≤ 6.5%, had lower LVEF% of 53.17 ± 14.55 vs. 57.8 ± 12.61 (p = 0.017), lower HDL of 1.046 ± 0.262 vs. 1.196 ± 0.295 (p < 0.001), more LVEF < 50% (30% vs. 15.6%; p = 0.017), ESV > 44 ml (38.2% vs. 20%; p = 0.005), and WMA (24.5% vs. 12.2%; p = 0.027), hypertension (77.3% vs. 54.4%; p = 0.001) and dyspnea (27.3% vs. 15.6%; p = 0.047), however, with less chest pain (70.9% vs. 83.3%; p = 0.039). Diabetic patients with HbA1c% > 7.5 had lower LVEF% (52.0 ± 14.59 vs. 57.6 ± 11.55; p = 0.018) and HDL (1.005 ± 0.239 vs 1.148 ± 0.273; p < 0.002), more LVEF < 50% (33.3% vs. 14.5%; p = 0.011), ESV > 44 ml (41.3% vs. 20.3%; p = 0.009), WMA (30.2% vs. 11.6%; p = 0.008), and EDV > 100 ml (34.9% vs. 18.8%; p = 0.037). No significant relation was found between HbA1c% and perfusion variables.ConclusionsElevated HbA1c% was associated with multiple abnormal MPGS function parameters including lower LVEF, greater ESV, and more WMA. The same was observed in the diabetic group, together with greater EDV. No significant relation was detected between HbA1c% and perfusion parameters. The effect of impaired glycemic control on cardiac function parameters, even in absence of significant effect on perfusion, could be an alarming sign, while interpreting MPGS studies, both in known diabetic patients and in those with probably insulin resistance but not known to be diabetic. Such findings may be calling for further investigations, to uncover the true mechanisms behind cardiac dysfunction and the possibility of associated microvascular disease.

Correlation of left ventricular mechanical dyssynchrony in patients with chronic kidney disease using phase analysis of gated single photon emission computed tomography myocardial perfusion imaging

Abstract Background Left ventricular mechanical dyssynchrony (LVMD) possesses deleterious effects that have been neglected in chronic kidney disease (CKD) as a cause of left ventricular dysfunction and further progression to heart failure, possibly contributing to sudden cardiac death in this population. Thus, cardiovascular risk assessment is essential in early stages of CKD as well as in the pre-transplant screening and this can be performed non-invasively by modalities including phase analysis Gated-SPECT myocardial perfusion imaging (MPI). This modality has emerged as a prognostic tool to predict mortality independent of MPI abnormalities as well as assessment of ventricular synchrony. Purpose The goal of this study is to evaluate the relationship of left ventricular mechanical dyssynchrony using phase analysis G-SPECT and chronic kidney disease severity and its predictors. Methods We included 567 patients who underwent one day rest/stress (dipyridamole) 99mTc-sestamibi myocardial perfusion imaging with G-SPECT for the following indications for testing: detection of CAD among asymptomatic patients, risk assessment during pre-operative evaluation for kidney transplantation and evaluation for noncardiac surgery without active cardiac conditions between January 2017 to January 2021. Data was collected including gender, age, risk factors resting heart rate and baseline blood pressure. Gated SPECT-MPI was performed according to the protocol rest followed by stress images (dipyridamole) 99mTc-sestamibi. The rest and stress phase analysis (histogram bandwidth, standard deviation of phase and entropy) parameters were compared between the five stages of chronic kidney disease. Data of the stress-rest difference in dyssynchrony was analyzed using McNemar's test; crude odds ratios and adjusted odds or multivariate analysis were done. Results Advanced CKD (Stage 4–5) shows statistically significant correlation with the Histogram bandwidth (HBW) both at stress (p=0.008) and rest (p=0.018), and stress entropy (p=0.007). As for the other stages, LVMD is present with similar results seen with the phase parameters HBW and PSD, the entropy values at rest than at stress for Stages I to IV (p&amp;lt;0.05). On further analysis, abnormal perfusion showed to be an independent predictor of left ventricular mechanical dyssynchrony across all arms. Other associated factors includes advanced CKD (stages 4–5), male sex, BMI ≥30 kg/m2, blood pressure and resting heart rate were significantly associated with increased odds of dyssynchrony across stress and rest tests. Overall, the full models were statistically significant, with R-squared ranging from 14.96% to 30.11% (p&amp;lt;0.001). Conclusion This study showed that CKD patients have left ventricular mechanical dyssynchrony on gated-SPECT MPI. Hence, it can be used as an alternative for early assessment and guide decision making for the treatment of patients with CKD to prevent further cardiovascular complication. Funding Acknowledgement Type of funding sources: None.

Clinical impacts of scar reduction on gated myocardial perfusion SPECT after cardiac resynchronization therapy

BackgroundIt had not been reported that myocardial scar shown on gated myocardial perfusion SPECT (GMPS) might reduce after cardiac resynchronization therapy (CRT). In this study, we aim to investigate the clinical impact and characteristic of scar reduction (SR) after CRT. Methods and ResultsSixty-one heart failure patients following standard indication for CRT received twice GMPS as pre- and post-CRT evaluations. The patients with an absolute reduction of scar ≥ 10% after CRT were classified as the SR group while the rest were classified as the non-SR group. The SR group (N = 22, 36%) showed more improvement on LV function (∆LVEF: 18.1 ± 12.4 vs 9.4 ± 9.9 %, P = 0.007, ∆ESV: − 91.6 ± 52.6 vs − 38.1 ± 46.5 mL, P < 0.001) and dyssynchrony (ΔPSD: − 26.19 ± 18.42 vs − 5.8 ± 23.0°, P < 0.001, Δ BW: − 128.7 ± 82.8 vs − 25.2 ± 109.0°, P < 0.001) than non-SR group (N = 39, 64%). Multivariate logistic regression analysis showed baseline QRSd (95% CI 1.019-1.100, P = 0.006) and pre-CRT Reduced Wall Thickening (RWT) (95% CI 1.016-1.173, P = 0.028) were independent predictors for the development of SR. ConclusionMore than one third of patients showed SR after CRT who had more post-CRT improvement on LV function and dyssynchrony than those without SR. Wider QRSd and higher RWT before CRT were related to the development of SR after CRT.

Improved risk-stratification in heart failure patients with mid-range to severe abnormalities of QRS duration and systolic function using mechanical dyssynchrony assessed by myocardial perfusion-gated SPECT

BackgroundThe use of left ventricular mechanical dyssynchrony (LVMD), which has been reported to be responsible for unfavorable outcomes, might improve conventional risk-stratification by clinical indices including QRS duration (QRSd) and systolic dysfunction in patients with heart failure (HF). Methods and resultsFollowing measurements of 12-lead QRSd and left ventricular ejection fraction (LVEF), three-dimensional (3-D) LVMD was evaluated as a standard deviation (phase SD) of regional mechanical systolic phase angles by gated myocardial perfusion imaging in 829 HF patients. Patients were followed up for a mean period of 37 months with a primary endpoint of lethal cardiac events (CEs). In an overall multivariate Cox proportional hazards model, phase SDs were identified as significant prognostic determinants independently. The patients were divided into 4 groups by combining with the cut-off values of LVEF (35% and 50%) and QRSd (130 ms and 150 ms). The groups with lower LVEF and prolonged QRSd more frequently had CEs than did the other groups. Patient groups with LVEF < 35% and with 35% ≦ LVEF < 50% were differentiated into low-risk and high-risk categories by using an optimal phase SD cut-off value of both QRSd thresholds. Conclusions3-D LVMD can risk-stratify HF patients with mid-range as well as severe abnormalities of QRSd and systolic dysfunction.

Diagnostic Accuracy of Gated-SPECT Myocardial Perfusion Imaging and Exercise Stress Test for Diagnosis of Coronary Artery Disease

Diagnostic Accuracy of Gated-SPECT Myocardial Perfusion Imaging and Exercise Stress Test for Diagnosis of Coronary Artery Disease

Myocardial perfusion findings evaluated by gated-SPECT in dyslipidemic very high-risk patients

Abstract Funding Acknowledgements Type of funding sources: None. Background. Dyslipidemia is one of the main risk factors for atherosclerotic disease. Timely diagnosis and appropriate treatment are therefore essential in the prevention and recurrence of cardiovascular disease (CVD). The detection of ischemia with myocardial perfusion gated-SPECT is a valuable diagnostic option that provides complete information to select the best therapeutic option, reducing morbidity and mortality in this group of patients. Purpose. To evaluate the findings of myocardial perfusion imaging (MPI) using gated-SPECT in a group of patients with dyslipidemia and very high cardiovascular risk. Methods. We retrospectively evaluated gated-SPECT results of 66 very high-risk dyslipidemic patients with a diagnosis or clinical suspicion of coronary artery disease (CAD). Exclusion criteria: structural heart disease, dilated hypertrophic cardiomyopathy, hemodynamic instability, low-intermediate risk. Rest-stress imaging with gated-SPECT Technetium-99m Sestamibi was acquired on a dedicated cardio gamma camera and subjectively evaluated in a 17-segment analysis. Ischemia was classified as mild, moderate, and severe. Statistical analysis: SPSS system, continuous data were expressed as mean ± SD, percentages were rounded; Chi-square and Student’s t-tests were used. Results. Mean age 61.06 ± 12.87 years old, 40 (61%) were men; 61 (92%) with primary and 5 (8%) with familial hypercholesterolemia. More than 80% have at least one or more cardiovascular (CV) risk factors; 73% have dyslipidemia, diabetes, and arterial hypertension, 52% tabaquism, 36% obesity, 11% kidney disease, and 30% family history of CV disease; all women were post-menopausal (44%). Asymptomatic (56%), 30% with dyspnea or equivalents, 9% atypical chest pain, and 5% typical angina. Gated-SPECT: 56% with ischemia; mild ischemia was present in 33% and 11% of men and women, and moderate in 35% and 27% respectively. Primary hypercholesterolemia: 26 % with mild, 28% moderate, and 46% without ischemia; 80% of familial hypercholesterolemia with moderate and 20% without ischemia. Conclusion. Myocardial ischemia was present in 56% of very high-risk dyslipidemic patients, predominantly in men (67.5%). Although 56% were asymptomatic, ischemia was detected in 54% of the patients with primary and 80% with familial hypercholesterolemia. It is advisable to perform MPI with gated-SPECT for the early detection of ischemia in high-risk dyslipidemic patients, even asymptomatic.

Left ventricular mechanical dyssynchrony in patients with chest pain and normal epicardial coronary arteries

BackgroundTo detect ischemia in patients with angina and normal coronaries frequently represents a complex diagnosis. MethodsTo investigate whether left ventricular mechanical dyssynchrony by phase analysis contributes in the evaluation of patients with chest pain and normal coronaries, gated-SPECT myocardial perfusion imaging (MPI) at rest and 30 minutes post-stress was performed in 218 patients with normal epicardial coronaries, who were divided into two groups: those with summed difference score (SDS) ≥ 4 (54 patients, Group 1), and those with SDS < 4 (164 patients, Group 2). Intraventricular synchronism-phase standard deviation (PSD) and histogram bandwidth (HBW)—was evaluated by phase analysis. ResultsWomen were significantly more frequent in Group 2 (those without ischemia in SPECT MPI): 113 (69%) vs 25 (46%), P = .00001. In males, left ventricular ejection fraction (LVEF) and ventricular volumes were not significantly different between patients with or without ischemia. However, ischemic females showed significantly higher ventricular volumes, minor post-stress LVEF and more negative delta LVEF (− 3.9 vs 0.34, P = .0008) than the non-ischemic ones. There was a significant post-stress increase of PSD and HBW among males, although not among females. According to SSS (≥ 4, with ischemia/necrosis; < 4, without ischemia/necrosis), post-stress PSD and HBW significantly increase both in male and female, and PSD and HBW were significantly higher in females with SSS ≥ 4 compared to those with SSS < 4 (PSD rest: 19.04° vs 11.72°, P < .0001; HBW rest: 58.85° vs 38.21°, P < .0001). PSD and HBW were also higher among males with SSS ≥ 4 compared to those with SSS < 4, although not significantly. ConclusionHigher ventricular volumes in females and dyssynchrony are associated with inducible ischemia in MPI in patients with chest pain and normal coronaries. Stress-induced ischemia increases degree of dyssynchrony.

Left-ventricular dyssynchrony in viable myocardium by myocardial perfusion SPECT is predictive of mechanical response to CRT.

Gated myocardial perfusion SPECT (GMPS) provides a one-stop-shop evaluation for cardiac resynchronization therapy (CRT). However, conflicting results have been observed regarding whether the baseline left-ventricular (LV) mechanical dyssynchrony as assessed by phase analysis on GMPS was predictive of therapeutic response to CRT. Since dyssynchrony parameters by phase analysis spuriously increased by scarred myocardium, the purpose of this study was to explore the value of dyssynchrony after stripping off the scar region in correlation to mechanical response to CRT. Forty-seven patients following standard indications for CRT received GMPS with phase analysis as pre-CRT evaluation. A decrease of end-systolic volume (ESV) > 15% on follow-up echocardiography after CRT was considered as a mechanical response to CRT. Myocardial regions with less than 50% of maximal activity on GMPS were considered as a scar. The phase standard deviation (PSD) and histogram bandwidth (BW) without or with stripping off scar were assessed by phase analysis of GMPS and were used for evaluation of LV dyssynchrony of all myocardium or only the viable myocardium, respectively. No significant difference was noted between mechanical responders (31 of 47 patients, 66%) and nonresponders ( 16 of 47 patients, 34%) for PSD (48.6° ± 19.4° vs 43.9° ± 20.7°, p = 0.46) and BW (225° ± 91.1° vs 163.5° ± 94.6°, p = 0.38) of the entire myocardium. However, responders had significantly larger PSD (40.5° ± 15.7° vs 30.5° ± 13.2°, p = 0.03) and borderlinely larger BW (215° ± 91.2° vs. 139.5° ± 78.2°, p = 0.05) than non-responders after stripping off scar. Logistic regression analysis showed that scar area and PSD after stripping off scar were independent predictors of mechanical response. Our result showed that LV dyssynchrony of the entire myocardium did not predict response to CRT. However, LV dyssynchrony only in the viable myocardium was a significant predictor of CRT mechanical response.

The use of mechanical dyssynchrony for predicting response to cardiac resynchronization therapy in patients with non-ischemic cardiomyopathy

Abstract Funding Acknowledgements Type of funding sources: None. Aim/Introduction: Assessment of mechanical dyssynchrony by myocardial perfusion gated-SPECT in patients with non-ischemic cardiomyopathy for predict response to cardiac resynchronization therapy (CRT). Materials and Methods We examined 32 patients with non-ischemic cardiomyopathy before and six months after CRT. Left ventricular mechanical dyssynchrony and contractility were assessed for all patients by myocardial perfusion gated-SPECT. The phase standard deviation (PSD), histogram bandwidth (HBW), phase histogram skewness (S) and phase histogram kurtosis (K) were used as an indicator of mechanical dyssynchrony for the both ventricles. Results Mechanical dyssynchrony of both ventricles before CRT was increased in all patients. Median value PSD 53°(41-61°), HBW 176°(136-202°), S 1,62(1,21-1,89), K 2,81(1,21-3,49). Six months after CRT 22(68%) respondents were identified. We divided the patients into two groups (responders and non-responders) and compared phase parameters. It was found that the PSD (44°(35-54°)) and HBW (158°(118-179°) in the responders were significantly lower than in the non-responders (PSD (68°(58-72°); HBW (205°(199-249°)). The value of phase histogram skewness and kurtosis in responders were significantly higher (Responders: S 1,77(1,62-2,02); K 3,03(2,60-3,58). Non-responders: S 1,21(0,93-1,31); K 1,21(0,19-1,46)). We found that all four indicators of mechanical dyssynchrony can predict CRT response according to the results of univariate logistic regression analysis. Moreover, It was found that only phase histogram kurtosis (OR = 1.196, 95% CI 1.04-1.37) is an independent predictor of CRT response according to multivariate logistic regression. Conclusion Radionuclide assessment of mechanical dyssynchrony may be the optimal diagnostic method for selecting patients with non-ischemic cardiomyopathy on CRT.

Value of intraventricular dyssynchrony assessment by gated-SPECT myocardial perfusion imaging in the management of heart failure patients undergoing cardiac resynchronization therapy (VISION-CRT)

BackgroundPlacing the left ventricular (LV) lead in a viable segment with the latest mechanical activation (vSOLA) may be associated with optimal cardiac resynchronization therapy (CRT) response. We assessed the role of gated SPECT myocardial perfusion imaging (gSPECT MPI) in predicting clinical outcomes at 6 months in patients submitted to CRT. MethodsTen centers from 8 countries enrolled 195 consecutive patients. All underwent gSPECT MPI before and 6 months after CRT. The procedure was performed as per current guidelines, the operators being unaware of gSPECT MPI results. Regional LV dyssynchrony (Phase SD) and vSOLA were automatically determined using a 17 segment model. The lead was considered on-target if placed in vSOLA. The primary outcome was improvement in ≥1 of the following: ≥1 NYHA class, left ventricular ejection fraction (LVEF) by ≥5%, reduction in end-systolic volume by ≥15%, and ≥5 points in Minnesota Living With Heart Failure Questionnaire (MLHFQ). ResultsSixteen patients died before the follow-up gSPECT MPI. The primary outcome occurred in 152 out of 179 (84.9%) cases. Mean change in LV phase standard deviation (PSD) at 6 months was 10.5°. Baseline dyssynchrony was not associated with the primary outcome. However, change in LV PSD from baseline was associated with the primary outcome (OR 1.04, 95% CI 1.01-1.07, P = .007). Change in LV PSD had an AUC of 0.78 (0.66-0.90) for the primary outcome. Improvement in LV PSD of 4° resulted in the highest positive likelihood ratio of 7.4 for a favorable outcome. In 23% of the patients, the CRT lead was placed in the vSOLA, and in 42% in either this segment or in a segment within 10° of it. On-target lead placement was not significantly associated with the primary outcome (OR 1.53, 95% CI 0.71-3.28). ConclusionLV dyssynchrony improvement by gSPECT MPI, but not on-target lead placement, predicts clinical outcomes in patients undergoing CRT.

Intraventricular synchronism assessment by gated-SPECT myocardial perfusion imaging in cardiac resynchronization therapy. Does cardiomyopathy type influence results?

PurposeTo analyze the evolution post-cardiac resynchronization therapy (CRT) in left ventricular non-compaction (LVNC) cardiomyopathy (CM) patients compared to other types of CM, according to clinical and functional variables, by using gated-SPECT myocardial perfusion imaging (MPI).MethodsNinety-three patients (60 ± 11 years, 28% women) referred for pre-CRT assessment were studied and divided into three groups: 1 (non-ischemic CM with LVNC, 11 patients), 2 (ischemic CM, 28 patients), and 3 (non-ischemic CM, 53 patients). All were studied by a 99mTc-MIBI gated-SPECT MPI at rest pre-CRT implantation and 6 ± 1 months after, including intraventricular dyssynchrony assessment by phase analysis. Quality of life was measured by the Minnesota Living with Heart Failure Questionnaire (MLHFQ).ResultsNo differences in sex, atherosclerotic risk factors other than smoking habit, and MLHFQ results were found among groups. LVNC CM patients were younger, with greater QRS width and lower left ventricular ejection fraction (LVEF) at baseline, but the differences were not significant. No significant differences were found at baseline regarding ventricular function, although end-systolic volume was slightly higher in LVNC CM patients. Mean SRS was significantly higher (p < 0.0001) in ischemic patients (14.9) versus non-ischemic ones (8.7 in group 1 and 9 in group 2). At baseline, LVNC CM patients were significantly more dyssynchronous: Their phase standard deviation (PSD) was higher (89.5° ± 14.2°) versus groups 2 (65.2° ± 23.3°) and 3 (69.7° ± 21.7°), p = 0.007. Although the quality of life significantly improved in all groups, non-ischemic patients (with or without LVNC) showed a higher LVEF increase and volumes reduction at 6 months post-CRT. Dyssynchrony reduced post-CRT in all groups. Nevertheless, those more dyssynchronous at baseline (LVNC CM) exhibited the most significant intraventricular synchronism improvement: PSD was reduced from 89.5° ± 14.2° at baseline to 63.7° ± 20.5° post-CRT (p = 0.028). Six months post-CRT, 89% of patients were responders: 11 (100%) of those with LVNC CM, 25 (86%) of those with ischemic CM, and 47 (89%) of patients with non-ischemic CM. No patient with LVNC CM had adverse events during the follow-up.ConclusionCRT contributes to a marked improvement in non-ischemic CM patients with non-compaction myocardium. Phase analysis in gated-SPECT MPI is a valuable tool to assess the response to CRT.

Effect of cardiac resynchronization therapy on septal perfusion and septal thickening: Association with left ventricular function, reverse remodelling and dyssynchrony

BackgroundWe evaluated the effect of cardiac resynchronization therapy (CRT) on septal perfusion and thickening at 6 months post implantation assessed on Tc99m-MIBI Gated myocardial perfusion SPECT (GMPS).We also studied the association of change in septal perfusion and thickening with primary outcome defined as at least one [improvement in ≥1NYHA class, left ventricular ejection fraction (LVEF) by ≥ 5%, reduction of end-systolic volume (ESV) by ≥ 15%, and improvement ≥ 5 points in Minnesota living with heart failure questionnaire (MLHFQ)]. MethodOne hundred and five patients underwent clinical and GMPS evaluation before and at 6 months post CRT. ResultPost CRT there was significant improvement in mean normalized septal perfusion uptake and in septal thickening (P value = 0.001, both). There was no significant relation between improvement in septal perfusion and primary outcome. However, improvement in septal thickening was statistically significant with favorable primary outcome (P = 0.001).There was no significant correlation between improvement of septal perfusion and improvement in LVEF, reduction in End diastolic volume (EDV), ESV, and Left ventricular Dyssynchrony (LVD). But, there was significant correlation between improvement of septal thickening and these parameters. ConclusionImprovement in septal thickening was associated with reverse remodeling, improvement in LVEF, and reduction of LVD.

Postexercise stunning in type II diabetes mellitus assessed by 2D speckle tracking echocardiography and gated-SPECT myocardial perfusion imaging

Background Type II diabetes mellitus (DM) is usually associated with a number of myocardial structural and functional changes. Noninvasive imaging techniques play a key role in the identification of these changes. Objective Detection of postexercise myocardium stunning in type II DM patients by 2 dimensional speckle tracking Echo (2D STE) and single photon emission computed tomography (SPECT) imaging. Patients and methods The authors enrolled 60 symptomatic patients with type II DM who were classified into different groups: Group I included 17 patients with normal left ventricular global longitudinal strain (LVGLS) and negative SPECT; group II included 43 patients with impaired LVGLS and negative SPECT; and group III included 10 patients with impaired LVGLS and positive SPECT. The authors evaluate LV functions and dimensions before and early after exercise by conventional, tissue Doppler, 2D STE, and gated-SPECT perfusion imaging. Coronary angiography for group III. Results This study shows statistically significant difference between early and late gated SPECT regarding left ventricular end diastolic volume (LVEDV) and EF% between the three different groups. There were significant decrease in average LVGLS from (−20.79±1.04 pre-exercise) vs (−16.15±1.28 postexercise) in group I from (−15.98±1.75 pre-exercise) vs (−14±2.47 postexercise) in group II and from (−15.82±3.44 pre-exercise) vs (−13.48±2.75 postexercise) in group III. Eight out of 10 patientﹶs had coronary artery disease in group III. Conclusion Transient ischemic stunning and dilatation remained a robust marker for high-risk scan especially in type II DM. LVGLS correlated well with gated SPECT in the detection of postexercise LV stunning. LVGLS is a very sensitive parameter and paramount for early detection of LV subclinical systolic dysfunction in diabetic patients.

P1477Right atrial and ventricular function assessed by speckle tracking in patients with inferior wall myocardial infarction

Abstract Background Right chambers involvement in left ventricular inferior wall myocardial infarction (LVIWMI) has a prognostic impact. Purpose To evaluate the influence of LVIWMI in right atrium (RA) and right ventricular (RV) mechanics. Methods We included 60 consecutive patients who underwent myocardial perfusion (MP) gated-SPECT for chest pain. We identify 30 patients with LVIWMI and 30 control individuals with normal MP. Comprehensive echocardiography was performed in all patients. RV free wall longitudinal strain (RVFWLS) and RA reservoir (RAr), contraction (RAct) and conduit (RAcd) phase strain were analyzed by 2D speckle tracking echocardiography (STE). Results RVFWLS (−26.1 vs 30.3, p&lt;0.01), RAr (peak strain) (31.5 vs 56.2, p&lt;0.01) and RAcd strain (12.5 vs 35, p=0.01) were significantly lower in the LVIWMI patients vs control individuals. In a logistic regression model, LVIWMI, reduced 3D LV and RV ejection fraction, mitral regurgitation and pulmonary hypertension were associated with reduction in RV an RA strain. Echocardiographic parameters LV inferior wall MI patients (n=30) Control subjects (n=30) p value 3D LV EDV (ml) (median, IQR) 121 (99.7–150) 89.5 (73–99) &lt;0.01 3D LV EF (%) (median, IQR) 46 (37–53) 60 (58–63) &lt;0.01 Mitral E/A (median, IQR) 0.82 (0.7–1.2) 1.21 (0.97–1.44) &lt;0.01 Medial E/e' (median, IQR) 9.59 (7.9–13) 7.7 (6.9–10.5) 0.01 RV EDD (mm) (mean, SD) 36.7±7.4 34.7±4.39 0.12 TAPSE (mm) (mean, SD) 18.6±5.05 21.7±4.1 &lt;0.01 RV FAC (%) (mean, SD) 37±9 46.8±7.24 &lt;0.01 RV S' (cm/s) (mean, SD) 9.9±2.7 11.8±1.85 &lt;0.01 3D RV EF (%) (median, IQR) 47.5 (42–52) 54 (49–57) &lt;0.01 RIMP (mean, SD) 0.49±0.2 0.46±0.12 0.60 SPAP (mmHg) (median, IQR) 31.5 (27–37) 29.5 (26–33) 0.07 Peak global LV LS (%) (median IQR) −13.35 (−17.6–9.3) −22 (−23.2–20.4) &lt;0.01 RV free wall LS (%) (median, IQR) −26.1 (−32.1–17.8) −30.3 (−36.6–27.5) &lt;0.01 RA peak strain (reservoir phase) (%) (median, IQR) 31.5 (25.2–43) 56.2 (47–66.4) &lt;0.01 RA contraction phase strain (%) (mean, SD) 20.17±10.4 24.4±10.36 0.07 RA conduit phase strain (%) (median, IQR) 12.5 (5.9–15.6) 35 (21–47.6) 0.01 Normal RVFW (A) and RA strain (B) Conclusion STE is a feasible technique for assessment of RVFW and RA deformation. Subclinical extension to RV in LVIWMI and its influence in RA mechanics could be assess by 2D-STE.

Gated SPECT myocardial perfusion imaging with cadmium-zinc-telluride detectors allows real-time assessment of dobutamine-stress-induced wall motion abnormalities

BackgroundLeft ventricular (LV) ejection fraction (EF) during high dobutamine stress (HD) by real-time gated-SPECT myocardial perfusion imaging (MPI) on a cadmium-zinc-telluride (CZT) gamma camera was validated versus cardiac magnetic resonance imaging (CMR). Methods and resultsAfter injecting 99mTc-tetrofosmin (320 MBq) in 50 patients (mean age 64 +/− 11 years), EF at rest and post-stress as well as relevant changes in EF at HD (ΔEF ≥ 5%) were assessed. CZT and CMR rest EF values yielded an excellent correlation and agreement (r = 0.96; P < 0.001; Bland–Altman limits of agreement (BA): + 0 to 14.8%). HD EF acquisition was feasible using CZT and correlated better to HD CMR EF than did post-stress CZT EF (r = 0.85 vs 0.76, respectively, all P < 0.001). Agreement in ΔEF detection between HD CMR and immediate post-stress CZT (reflecting standard acquisition using conventional SPECT camera unable to scan during stress) was 45%, while this increased to 85% with real-time HD CZT scan. ConclusionReal-time ultrafast dobutamine gated-SPECT MPI with a CZT device is feasible and provides accurate measurements of HD LV performance.

Prognostic value of left ventricular dyssynchrony evaluated by gated myocardial perfusion imaging in patients with chronic kidney disease and normal perfusion defect scores

BackgroundThis study aimed to investigate whether indices of left ventricular (LV) dyssynchrony by gated myocardial perfusion SPECT (GMPS) could be useful to predict prognosis in chronic kidney disease (CKD) patients with normal perfusion defect scores. MethodsOne hundred and sixty-seven CKD patients with normal perfusion defect scores on adenosine-stress 201Tl GMPS and no previous history of overt heart diseases were enrolled. Phase standard deviation (PSD) and bandwidth (BW) were automatically calculated from GMPS. The major adverse cardiac events (MACEs) for a mean of 560 days were defined as sudden cardiac death, fatal arrhythmias, and acute coronary syndrome requiring urgent coronary revascularization. Patients were divided into two groups according to the presence or absence of MACEs. ResultsThe MACEs occurred in 12 patients (7.1%). Patients who experienced MACEs showed significantly higher PSD and wider BW than those who did not. In the Kaplan-Meier event-free survival analysis, cardiac event rate was significantly higher in the high-PSD and wide-BW group (n = 81) than in the low-PSD and narrow-BW group (n = 71) (P = .002). The multivariate regression analysis revealed that the PSD was associated with MACEs (odds ratio 1.33, 95% confidence interval 1.05-1.69, P = .01). ConclusionThe LV dyssynchrony indices from GMPS may be novel prognostic predictors in CKD patients with normal perfusion defect scores.

Comparison of the dyssynchrony parameters recorded with gated SPECT in ischemic cardiomyopathy according to their repeatability at rest and to their ability to detect a synchrony reserve under dobutamine infusion

BackgroundThis study aimed to determine whether the repeatability of dyssynchrony assessment using gated myocardial perfusion SPECT (GSPECT) allows the detection of synchrony reserve during low-dose dobutamine infusion. Methods and ResultsSixty-one patients with ischemic cardiomyopathy and LV ejection fraction < 50% were prospectively included in 10 centers. Each patient underwent two consecutive rest GSPECT with 99mTc-labeled tracer (either tetrofosmin or sestamibi) to assess the repeatability of LV function and dyssynchrony parameters, followed by a GSECT acquisition during low-dose dobutamine infusion. LV dyssynchrony was assessed using QGS software through histogram bandwidth (BW), standard deviation of the phase (SD), and entropy. Repeatability was assessed with Lin’s concordance correlation coefficient (CCC). Entropy showed a higher CCC (0.80) compared to BW (0.68) and SD (0.75). On average, dobutamine infusion yielded to improve both BW (P = .049) and entropy (P = .04) although significant improvements, setting outside the 95% confidence interval of the repeatability analysis, were documented in only 6 and 4 patients for BW and entropy, respectively. ConclusionsA synchrony reserve may be documented in patients with ischemic cardiomyopathy through the recording of BW and entropy with low-dose dobutamine GSPECT, with the additional advantage of a higher repeatability for entropy.

Association between non-perfusion parameters and presence of ischemia in gated-SPECT myocardial perfusion imaging studies

BackgroundCombined assessment of perfusion and function improves diagnostic and prognostic power of gated-SPECT in patients with coronary artery disease. The aim of this study was to investigate whether the presence of stress-induced ischemia is associated with abnormal resting left ventricular (LV) function and intraventricular dyssynchrony. Methods and ResultsGated-SPECT myocardial perfusion imaging (MPI) at rest and 15 min post-stress was performed in 101 patients, who were divided into three groups: those with stress-induced ischemia (Group 1, n = 58), those with normal scans (Group 2, n = 28), and those with scar but no ischemia (Group 3, n = 15). More extensive perfusion defects were found in patients of Groups 1 and 3 [Summed stress score (SSS): 13 ± 8 and 21 ± 9, respectively]. In Group 2, the mean SSS was 1.5. The mean change in LV ejection fraction (LVEF at stress − LVEF at rest) was higher in Group 1 v. Group 2 patients: −5.54% ± 6.24% vs −2.46% ± 5.56%, p = 0.02. Group 3 patients also had higher values, similar to Group 1: −6.47% ± 8.82%. Patients with ischemia had almost 50% higher end-diastolic volumes than patients with normal MPI. Similarly, end-systolic volumes were almost twice as high in this group (p < 0.0001). In addition, the histogram bandwidth, a measure of intraventricular dyssynchrony, was greater in Group 1. ConclusionsBaseline differences in left ventricular volumes and degree of dyssynchrony are associated with inducible ischemia on stress testing in a gated-SPECT MPI. Stress-induced ischemia increases the degree of intraventricular dyssynchrony.

Assessment of Left Ventricular Dyssynchrony using Gated Myocardial Perfusion SPECT in Cardiac Resynchronization Therapy

In cardiac resynchronization therapy (CRT), even if patient selection is made according to Japanese adaptive criteria, there are non-responders. Its main factor is considered to be the lack of adequate preoperative assessment against mechanical left ventricular dyssynchrony. Recently, phase analysis was enabled on gated myocardial perfusion SPECT (GMPS). The purpose of this study was to examine the relationship between the index of phase analysis using the two software (cardioREPO® and QGS) and the left ventricular reverse remodeling index (ΔLVESV) for the evaluation of left ventricular dyssynchrony in CRT patients is there. It also evaluated whether it could be an index of adaptation decision and effect determination. Methods: For 15 patients with severe heart failure who underwent CRT, GMPS was performed before (baseline) and after CRT. In cardioREPO®, standard deviation of the time to end systolic phase of 17 segments of the left ventricle (SDTES) and Bandwidth and Phase SD, Entropy of phase histogram were used as left ventricular dyssynchrony index. In QGS, standard deviation of the time to maximum displacement of each segment (SDTTMD) was used as an index. An example in which ΔLVESV (%Reduction) after 6 months of CRT decreased by 15% or more was defined as a CRT responder. Results: 10 of 15 patients were responders. Bandwidth at baseline of the responder group was significantly higher. SDTES, Phase SD, Entropy and SDTTMD of the responder group tended to be higher. All indexes decreased significantly in the responder group after 6 months of CRT but not in the non-responder group. Excluding SDTES, positive correlation was shown between baseline and ΔLVESV, and the optimal cutoff value of responder prediction was SDTES 7.637%, Bandwidth 218°, Phase SD 50.0°, Entropy 0.785, SDTTMD 19.85 ms. Conclusion: Phase analysis by GMPS showed that quantitative assessment of left ventricular dyssynchrony of CRT was possible and that the index was related to response prediction to CRT. In particular, SDTTMD showed good correlation between baseline and ΔLVESV, suggesting that it may be a more sensitive index of reaction prediction.