Gender differences in the diagnostic accuracy of SPECT myocardial perfusion imaging: A bivariate meta-analysis

Background

It remains controversial whether the diagnostic accuracy of single-photon emission computed tomography myocardial perfusion imaging (SPECT MPI) is different in men as compared to women. We performed a meta-analysis to investigate gender differences of SPECT MPI for the diagnosis of CAD (≥50% stenosis).

Method

Two investigators independently performed a systematic review of the MEDLINE and EMBASE databases from inception through January 2012 for English-language studies determining the diagnostic accuracy of SPECT MPI. We included prospective studies that compared SPECT MPI with conventional coronary angiography which provided sufficient data to calculate gender-specific true and false positives and negatives. Data from studies evaluating <20 patients of one gender were excluded. Bivariate meta-analysis was used to create summary receiver operating curves.

Results

Twenty-six studies met inclusion criteria, representing 1,148 women and 1,142 men. Bivariate meta-analysis yielded a mean sensitivity and specificity of 84.2% (95% confidence interval [CI] 78.7%-88.6%) and 78.7% (CI 70.0%-85.3%) for SPECT MPI in women and 89.1% (CI 84.0%-92.7%) and 71.2% (CI 60.8%-79.8%) for SPECT MPI in men. There was no significant difference in the sensitivity (P = .15) or specificity (P = .23) between male and female subjects.

Conclusion

In a bivariate meta-analysis of the available literature, the diagnostic accuracy of SPECT MPI is similar for both men and women.     

心肌灌注显像常见伪影分析

伪影是造成心肌灌注显像出现假阳性的主要原因之一,有必要对造成伪影的因素、伪影的表现形式和校正方法进行系统、全面的认识。心肌灌注显像中的伪影主要可归结为与检测仪器有关的伪影,与病人因素有关的伪影,与图像处理有关的伪影,以及与非冠状动脉疾病有关的伪影等。     

Radiopharmaceuticals for imaging myocardial perfusion

A replacement for 201Tl used in myocardial perfusion imaging with a 99mTc-labeled complex is a long-sought goal. Now, at least three varieties of 99mTc-complexes are being made available for clinical studies. This review summarizes the development of these agents and presents basic research data accumulated in this area. Also, relevant clinical radiopharmaceutical protocols and relative merits of competing 99mTc-agents are discussed.     

Molecular imaging will replace myocardial perfusion imaging

Conclusion   “The order is rapidly fadin’. And the first one now will later be last ...” In 2008 myocardial perfusion imaging is the main-stay of nuclear cardiology. However, the lyrics of Dylan from the 1960s are applicable today, as we are in rapidly changing times in medicine. We are seeing a paradigm shift in disease detection and treatment from a focus on cardiovascular morphology, function, and pathophysiology to genetic and molecular events. Cardiovascular molecular imaging will be the vanguard of noninvasive imaging in this era. Nuclear cardiology is uniquely positioned to play a central role in both the clinical and research applications of cardiovascular molecular imaging. The question should not be whether myocardial perfusion imaging will remain the dominant clinical application but how does nuclear cardiology transition to embrace and foster cardiovascular molecular imaging. If we do not do this, there are several other imaging specialties that will be more than willing to fill this void.     

Dynamic CT myocardial perfusion imaging

Cardiac CT offers several approaches to establish the hemodynamic severity of coronary artery obstructions. Dynamic myocardial perfusion CT (MPI_CT) is based on serial CT imaging to measure the inflow of contrast medium into the myocardium and calculate absolute measures of myocardial perfusion. This review describes the MPI_CT acquisition protocol, post-image acquisition processing and calculation of quantitative parameters, the diagnostic performance of MPI_CT and the potential incremental value of this technique in comparison to alternative approaches. Further technical innovation using different scanner platforms and establishment of reproducible diagnostic thresholds to differentiate significant coronary artery disease will be crucial in the path to broader clinical implementation.     

Acute myocardial perfusion imaging for the technologist

Conclusion  Acute myocardial perfusion imaging involves careful planning from the nuclear medicine or nuclear cardiology laboratory to ensure optimal results are achieved. The role of the technologist is to ensure a high-quality study is performed on every patient who is referred to the laboratory. This is one of the most important roles because the decision for further evaluation can be based on the interpretation of the acute images. When acute myocardial perfusion imaging is used appropriately, in conjunction with standard methods of evaluation for patients presenting to the emergency department with chest pain syndromes perceived to be cardiac in origin, it can be of great benefit. It offers a more definitive diagnosis of chest pain syndromes and can be used to reduce the expense of otherwise costly hospital stays, even in patients with moderate risk of ischemic heart disease.     

Evaluation of the American College of Cardiology Foundation/American Society of Nuclear Cardiology appropriateness criteria for SPECT myocardial perfusion imaging

Background. The American College of Cardiology Foundation/American Society of Nuclear Cardiology appropriateness criteria (AC) were created to guide responsible use of single photon emission computed tomography (SPECT). Clinical applicability of the AC has not been evaluated. Methods and Results. Indications for testing were determined in 1209 patients and categorized as having appropriate, uncertain, or inappropriate indications; the specialty of the ordering physician was noted. There were 940 (80%) appropriate, 154 (13%) inappropriate, and 79 (7%) uncertain tests; 36 tests were labeled “no category,” as these were ordered for indications not clearly addressed in the AC. Inappropriate studies had more normal and lower summed stress scores, although there remained a high proportion of abnormal SPECT studies in this group (26% of women and 50% of men). Women had lower summed stress scores and more normal tests in the appropriate and inappropriate groups. Studies ordered by anesthesiologists for preoperative evaluation were more likely to be deemed inappropriate than other specialty groups. Conclusion. In evaluating the AC in a single-center academic setting, the majority of studies are appropriate, but a large proportion of ordered SPECT studies were categorized as uncertain, inappropriate, or no category. Although the inappropriate studies showed less ischemia than other groups, especially in women, a substantial portion of these studies (32%) were abnormal.     

Correlation between clinical outcomes and appropriateness grading for referral to myocardial perfusion imaging for preoperative evaluation prior to non-cardiac surgery

Background  

In a previous study, we have found that referral to myocardial perfusion imaging (MPI) for preoperative evaluation of patients before non-cardiac surgery was the most common cause of inappropriate referral based on AHA/ACC Appropriate Use Guidelines, though 40% of scans graded as inappropriate had abnormal MPI results. The aim of this study was to correlate appropriateness grading with (1) the outcome of MPI scans, and (2) the clinical outcome of patients after surgery, so as to determine if the predictive value of MPI was related to appropriateness grading.     

Quantitative aspects of myocardial perfusion imaging

Computer quantitation of myocardial perfusion images has enhanced the detection of thallium perfusion abnormalities compared to visual analysis. Computer analysis is more specific than visual analysis for detection of initial defects and more sensitive for detection of redistribution. Computer analysis is equally good for detecting thallium abnormalities in the distribution of the three major coronary arteries. Measurement of absolute clearance of thallium results in an unacceptable high false-positive rate. However, when clearance in a myocardial segment is compared to the fastest clearing segment in the heart, the specificity of clearance improves significantly. Quantitation of lung:heart ratio is very useful. Increased lung:heart ratio reflects exercise induced left ventricular dysfunction and is a strong marker of prognosis. Single photon emission computerized tomography (SPECT) offers the potential of more precisely sizing the risk area. The question of whether this technique offers a significant advantage over planar thallium imaging has to be answered.     

Acute myocardial infarction during adenosine myocardial perfusion imaging

Journal of Nuclear Cardiology -     

Artifacts and pitfalls in myocardial perfusion imaging

Myocardial perfusion imaging (MPI) is an important imaging modality in the management of patients with cardiovascular disease. MPI plays a key role in diagnosing cardiovascular disease, establishing prognosis, assessing the effectiveness of therapy, and evaluating viability. However, MPI is a complex process, subject to a variety of artifacts and pitfalls, which may limit its clinical utility. These factors may be related to the patient (including unique aspects of the patient's heart), the nuclear medicine equipment, or the actions of the technologist. After reviewing this article, the reader should be familiar with the causes and the effects of these potential artifacts and pitfalls. The reader should develop an understanding of steps to limit these factors, actions to correct them if they do arise and, when necessary, how to incorporate their influence into the interpretation of the study.     

Selective adenosine agonists and myocardial perfusion imaging

Selective adenosine receptor agonists have several advantages for use as stress agents in conjunction with myocardial perfusion imaging compared to the non selective agents such as adenosine and dipyridamole. This review will summarize the pre-clinical and clinical data on the selective adenosine agonist stress agents regadenoson (Lexiscan^®), binodenoson (CorVue?) and apadenoson (Stedivaze?) that have been studied so far with focus on regadenoson that has the most clinical data published so far. The article will review the adenosine receptor types and properties. It will also review the various attributes of the selective adenosine agonists including their pharmacology, pharmacokinetics and pharmacodynamics, their coronary vasodilatory and hemodynamic effects, their safety and side effects, their interactions with other drugs and their use with myocardial perfusion imaging. The landmark trials of the selective adenosine agonists will be reviewed as well as their use in special patient populations undergoing stress myocardial perfusion imaging.