2D-STI combined with gated 99Tcm-MIBI MPI for the diagnosis of myocardial ischemia in hypercholesterolemia patients.
ABSTRACT: This study aimed to investigate the reliability of ultrasound two-dimensional speckle tracking imaging (2D-STI) for the evaluation of myocardial ischemia in familial hypercholesterolemia (FH) patients. We recruited 28 patients clinically diagnosed with homozygous familial hypercholesterolemia (HoFH) and subjected them to 2D-STI, gated transthoracic Doppler echocardiography (TTDE), and 99Tcm-methoxyisobutylisonitrile myocardial perfusion imaging (99Tcm-MIBI MPI). The sensitivity, specificity and diagnostic accordance rate of TTDE and 2D-STI for myocardial ischemia in HoFH patients were compared with the 99Tcm-MIBI scores. According to the diagnosis of ischemia in the three main coronary arteries (LAD, LCX, and RCA) by MPI, patients were further divided into different groups for comparing segmental strain by 2D-STI. The total correlation between TTDE and 99Tcm-MIBI MPI for evaluation of myocardial ischemia was r=0.483 and between 2D-STI and 99Tcm-MIBI MPI was 0.786. The total correlation index for ejection fraction (EF) between TTDE and 99Tcm-MIBI MPI was r=0.606 and for 2D-STI and 99Tcm-MIBI MPI was r=0.919. TTDE indicated that differences among LVDd, LVDs, IVS, LVPW, AO Vmax, PG, E/e', and DT were statistically significant. STI indicated that the total strain of the ischemia group was lower than that of the non-ischemia group. The total systolic strain and total early diastolic strain of the ischemia group were lower than that of the non-ischemia group. TTDE can be used for primary observation and evaluation of ventricular wall ischemia for HoFH patients. Ultrasound 2D-STI is better than TTDE in the evaluation of myocardial ischemia in HoFH patients. Ultrasound 2D-STI shows the same effectiveness as 99Tcm-MIBI MPI for the detection of myocardial ischemia, serving as good tool for prognosis and treatment evaluation in HoFH patients.
Project description:Prevention of the no-reflow phenomenon has a crucial role in primary percutaneous coronary intervention (P-PCI) procedures.To assess the effects of early intracoronary administration of nicorandil (NIC) during P-PCI on myocardial microcirculation in patients with acute myocardial infarction (AMI).A total of 120 patients with first acute anterior wall ST segment elevation myocardial infarction who underwent P-PCI were randomly divided into two groups: the NIC group (A, n = 60) and the placebo group (B, n = 60). Before stent placement, NIC or normal saline was injected using a guiding catheter. The thrombolysis in myocardial infarction (TIMI) grade, TIMI myocardial perfusion grade (TMPG), resolution of ST segment elevation (defined as > 50% decrease in ST elevation) 1 h after surgery, and 99Tcm-methoxyisobutyl isocyanide (MIBI) rest myocardial perfusion imaging (MPI) via single-photon emission computed tomography (99Tcm-MIBI SPECT) findings 10 days after surgery were compared between the two groups.The number of patients who achieved TIMI grade 3 (96.67% vs. 86.67%; p = 0.047) and TMPG 3 (95% vs. 83.33%; p = 0.040) was higher in the NIC group than in the placebo group. Resolution of ST segment elevation occurred in 95% and 81.67% of the patients in the NIC and placebo groups, respectively (p = 0.023); the MPI score of the two groups was 4.1 ±1.89 and 7.3 ±2.65, respectively (p = 0.014).Early coronary administration of NIC can significantly reduce the damage in the myocardial microcirculation caused by P-PCI and the myocardial infarct size in patients with AMI.
Project description:BACKGROUND:Exercise stress electrocardiography (ECG) alone is underutilized in part due to poor diagnostic accuracy. High-frequency QRS analysis (HF-QRS) is a novel tool to supplement ST evaluation during stress ECG. We compared the diagnostic accuracy and net reclassification of HF-QRS analysis compared with ST evaluation for substantial myocardial ischemia by exercise SPECT myocardial perfusion imaging (MPI). METHODS AND RESULTS:Exercise SPECT MPI was performed in 257 consecutive eligible patients (mean age 59?±?12, 67% male). An ischemic HF-QRS pattern was defined as a???1 µV absolute reduction and a???50% relative reduction of the root-mean-square of the 150-250 Hz band signal in???3 leads. Left ventricular ischemia of???10% on SPECT MPI was the diagnostic standard for substantial myocardial ischemia. HF-QRS analysis demonstrated incremental diagnostic value to ST evaluation plus clinical risk factors (AUC 0.804 vs 0.749, P?<?.0001). A HF-QRS?+?ST -analysis strategy identified 92.3% of subjects with substantial ischemia and no abnormality in 59.9% of the cohort. No cardiac events occurred in patients without substantial ischemia identified by HF-QRS analysis. CONCLUSIONS:In this prospective analysis, exercise stress ECG with HF-QRS analysis identified any and substantial ischemia with high diagnostic accuracy and may allow more than half of referred patients to safely avoid imaging.
Project description:BACKGROUND: In patients with ischemic heart disease, accurate assessment of the extent of myocardial perfusion deficit may be important in predicting prognosis of clinical cardiac outcomes. The aim of this study was to compare the ability of three dimensional (3D) and of two dimensional (2D) multi-slice myocardial perfusion imaging (MPI) using cardiovascular magnetic resonance (CMR) in determining the size of defects, and to demonstrate the feasibility of 3D MPI in healthy volunteers at 3 Tesla. METHODS: A heart phantom was used to compare the accuracy of 3D and 2D multi-slice MPI in estimating the volume fraction of seven rubber insets which simulated transmural myocardial perfusion defects. Three sets of cross-sectional planes were acquired for 2D multi-slice imaging, where each set was shifted along the partition encoding direction by +/- 10 mm. 3D first-pass contrast-enhanced (0.1 mmol/kg Gd-DTPA) MPI was performed in three volunteers with sensitivity encoding for six-fold acceleration. The upslope of the myocardial time-intensity-curve and peak SNR/CNR values were calculated. RESULTS: Mean/standard deviation of errors in estimating the volume fraction across the seven defects were -0.44/1.49%, 2.23/2.97%, and 2.59/3.18% in 3D, 2D 4-slice, and 2D 3-slice imaging, respectively. 3D MPI performed in healthy volunteers produced excellent quality images with whole left ventricular (LV) coverage. Peak SNR/CNR was 57.6 +/- 22.0/37.5 +/- 19.7 over all segments in the first eight slices. CONCLUSION: 3D performed better than 2D multi-slice MPI in estimating the size of perfusion defects in phantoms. Highly accelerated 3D MPI at 3T was feasible in volunteers, allowing whole LV coverage with excellent image quality and high SNR/CNR.
Project description:FFR provides an accurate and reproducible assessment of the functional severity of coronary stenosis. Whereas stress testing remains the preferred initial modality for assessment of ischemia, there is limited data comparing it with FFR. We sought to determine the correlation between cardiac stress testing and coronary fractional flow reserve (FFR) measurement for assessing the presence, location, and burden of myocardial ischemia in patients referred for evaluation of coronary artery disease (CAD).Over 5-year study period, of the 5420 consecutive coronary angiograms that were screened, 326 patients had FFR measurements. Of these, 96 patients with FFR measurements who had a preceding stress test (stress echocardiography [SE] or myocardial perfusion imaging [MPI]) within a year were included.Of the 96 patients, there were 46 (48%) men and 50 (52%) women with a mean age of 61 ± 10 years. SE was performed in 57 (59.3%) and MPI in 32 (40.7%) of patients. FFR was ?0.79 in 54 (56%) patients. Stress testing had low sensitivity (55%) and specificity (47%) compared to FFR. The concordance between FFR and stress testing was low for both presence (k=0.03) and location (k=0.05) of the ischemic territory. The number of ischemic vascular territories was correctly estimated in only 39% of the stress tests. SE was more likely to overestimate and MPI more likely to underestimate extent of ischemia.In patients referred for evaluation of CAD, there was poor correlation between stress testing and FFR. A prospective study comparing these two modalities with FFR is needed.
Project description:Myocardial perfusion imaging (MPI) has limitations in the presence of balanced multivessel disease (MVD) and left main (LM) coronary artery disease, occasionally resulting in false-normal results despite the high cardiovascular risk associated with this condition. The purpose of this study was to assess the incidence of severe coronary artery disease (CAD) in the presence of a very high Agatston coronary artery calcium (CAC) score (>1,000) in stable symptomatic patients without known CAD but with normal MPI results.A total of 2,659 prospectively acquired consecutive patients were referred for MPI and evaluation of CAC score by CT. Of this patient population, 8 % (222/2,659) had ischemia without myocardial infarction (MI) on MPIand 11 % (298/2,659) had abnormal MPI (MI and/or ischemia). On presentation 1 % of the patients (26/2,659) were symptomatic, had a CAC score >1,000 and normal MPI results. The definition of normal MPI was strict and included a normal hemodynamic response without ischemic ECG changes and normal imaging, particularly absence of transient ischemic dilation. All of these 26 patients with a CAC score >1,000 and normal MPI findings underwent cardiac catheterization.Of these 26 patients, 58 % (15/26) had severe disease (?70 % stenosis) leading to revascularization. Of this group, 47 % (7/15) underwent percutaneous intervention, and 53 % (8/15) underwent coronary artery bypass grafting. All of these 15 patients had either MVD (14/15) or LM coronary artery disease (1/15), and represented 0.6 % (15/2,659) of all referred patients (95 % CI 0.3 - 0.9 %). The majority, 90 % (8/9), had severe CAD with typical chest pain.A very high CAC score (>1,000) with normal MPI in a small subset of symptomatically stable patients was associated with a moderate incidence of severe CAD (95 % CI 37 - 77 %). Larger studies and/or a meta-analysis of small studies are needed to more precisely estimate the incidence of CAD in this population. This study also supports the concept that a normal MPI result in patients with severe CAD may be due to balanced MVD.
Project description:The prevalence of ischemia on nuclear myocardial perfusion imaging (MPI) has been decreasing. Recent research has questioned the benefit of invasive revascularization for patients with moderate to severe ischemia. We hypothesized that patients with moderate to severe ischemia could routinely undergo successful revascularization.We analyzed data from 544 patients who underwent an MPI at a single academic Veterans Affairs Medical Center. Patients with moderate to severe ischemia, defined as a summed difference score (SDS) 8 or greater, were compared to the rest of the cohort.Of the total cohort (n?=?544), 39 patients had MPI studies with resultant moderate to severe ischemia. Patients with ischemia were more likely to develop coronary artery disease (74.4% versus 38.8%, P?<?0.0001) and have successful revascularization (38.5% versus 4.0%, P?<?0.0001) during the following year. Revascularization was attempted in 31 patients with moderate to severe ischemia, though only 15 (47%) of these attempts were successful. Ischemia was predictive of myocardial infarction (5.1% versus 0.8%, P?=?0.01) within 1 year.Moderate to severe ischemia is an uncommon finding in a contemporary nuclear laboratory. Among patients with ischemia, revascularization is typically attempted but is frequently unsuccessful.This trial does not appear on a registry as it is neither randomized nor prospective.
Project description:BACKGROUND:Coronary artery disease (CAD) is the leading cause of death in patients with type 2 diabetes mellitus (T2DM) and may be asymptomatic. OBJECTIVE:The objective of this study was to assess the prevalence of asymptomatic myocardial ischemia in patients with T2DM using stress myocardial perfusion imaging. METHODS:We evaluated 97 consecutive patients with T2DM without clinical evidence of CAD presenting to Cardiology and Endocrinology clinics using Tc-99m MIBI gated single-photon emission-computed tomography (SPECT) myocardial perfusion imaging for the presence of asymptomatic CAD. RESULTS:Abnormal myocardial perfusion was observed in 10 patients (10.3%). Of these, one half of patients had reversible myocardial perfusion defects suggestive of inducible myocardial ischemia. The other half had fixed perfusion defects suggestive of previous silent myocardial infarctions. Small and moderate reversible perfusion defects were observed in 3 and 2 patients, respectively. The fixed perfusion defects observed in 5 patients were medium sized. The presence of asymptomatic ischemia was significantly associated with age and smoking but not with other traditional cardiac risk factors. CONCLUSION:Ten percent of patients with T2DM with no clinical evidence of CAD were found to have evidence of asymptomatic ischemia or infarction.
Project description:Multidetector coronary computed tomography angiography (CTA) is a promising modality for widespread clinical application because of its noninvasive nature and high diagnostic accuracy as found in previous studies using 64 to 320 simultaneous detector rows. It is, however, limited in its ability to detect myocardial ischemia. In this article, we describe the design of the CORE320 study ("Combined coronary atherosclerosis and myocardial perfusion evaluation using 320 detector row computed tomography"). This prospective, multicenter, multinational study is unique in that it is designed to assess the diagnostic performance of combined 320-row CTA and myocardial CT perfusion imaging (CTP) in comparison with the combination of invasive coronary angiography and single-photon emission computed tomography myocardial perfusion imaging (SPECT-MPI). The trial is being performed at 16 medical centers located in 8 countries worldwide. CT has the potential to assess both anatomy and physiology in a single imaging session. The co-primary aim of the CORE320 study is to define the per-patient diagnostic accuracy of the combination of coronary CTA and myocardial CTP to detect physiologically significant coronary artery disease compared with (1) the combination of conventional coronary angiography and SPECT-MPI and (2) conventional coronary angiography alone. If successful, the technology could revolutionize the management of patients with symptomatic CAD.
Project description:The relationship between inappropriate MPI and cardiovascular outcomes is poorly understood. We sought to systematically review the literature on appropriate use criteria (AUC) for MPI, including temporal trend of inappropriate testing and resulting cardiovascular outcomes.We searched the MEDLINE database for studies related to AUC and MPI. The co-primary outcomes were abnormal test results and the presence of cardiac ischemia. Random effects odds ratios (OR) were constructed using DerSimonian-Laird method.A total of 22 studies with 23,443 patients were included. The prevalence of inappropriate testing was 14.8% [95% confidence interval (CI) 11.6%-18.7%]. Inappropriate MPI studies were less likely to be abnormal (OR 0.41 95% CI 0.35-0.49, P < .0001) and to demonstrate ischemia (OR 0.40, 95% CI 0.24-0.67, P < .0001) compared to appropriate testing. No difference in the rate of inappropriate tests was detected based on the midpoint of the enrollment year (P = .54). The pattern of ordering inappropriate studies was not different between cardiology and non-cardiology providers (OR 0.74, 95% CI 0.51-1.06, P = .10).Inappropriate MPI studies are less likely to yield abnormal results or demonstrate myocardial ischemia. The rate of inappropriate MPI has not decreased over time.
Project description:Coronary artery disease (CAD) remains the leading cause of death and morbidity worldwide. To date, diagnostic evaluation of patients with suspected CAD has relied upon the use of physiologic non-invasive testing by stress electrocardiography, echocardiography, myocardial perfusion imaging (MPI) and magnetic resonance imaging. Indeed, the importance of physiologic evaluation of CAD has been highlighted by large-scale randomized trials that demonstrate the propitious benefit of an integrated anatomic-physiologic evaluation method by performing lesion-specific ischemia assessment by fractional flow reserve (FFR)-widely considered the "gold" standard for ischemia assessment-at the time of invasive angiography. Coronary CT angiography (CCTA) has emerged as an attractive non-invasive test for anatomic illustration of the coronary arteries and atherosclerotic plaque. In a series of prospective multicenter trials, CCTA has been proven as having high diagnostic performance for stenosis detection as compared to invasive angiography. Nevertheless, CCTA evaluation of obstructive stenoses is prone to overestimation of severity and further, detection of stenoses by CCTA does not reliably determine the hemodynamic significance of the visualized lesions. Recently, a series of technological innovations have advanced the possibility of CCTA to enable physiologic evaluation of CAD, thereby creating the potential of this test to provide an integrated anatomic-physiologic assessment of CAD. These advances include rest-stress MPI by CCTA as well as the use of computational fluid dynamics to non-invasively calculate FFR from a typically acquired CCTA. The purpose of this review is to summarize the most recent data addressing these 2 physiologic methods of CAD evaluation by CCTA.