Faculty Bibliography

There is a preponderance of evidence that, in the setting of an acute coronary syndrome, an invasive approach using coronary revascularization has a morbidity and mortality benefit. However, recent stable ischemic heart disease (SIHD) randomized clinical trials testing whether the addition of coronary revascularization to guideline-directed medical therapy (GDMT) reduces death or major cardiovascular events have been negative. Based on the evidence from these trials, the primary role of GDMT as a front line medical management approach has been clearly defined in the recent SIHD clinical practice guideline; the role of prompt revascularization is less precisely defined. Based on data from observational studies, it has been hypothesized that there is a level of ischemia above which a revascularization strategy might result in benefit regarding cardiovascular events. However, eligibility for recent negative trials in SIHD has mandated at most minimal standards for ischemia. An ongoing randomized trial evaluating the effectiveness of randomization of patients to coronary angiography and revascularization as compared to no coronary angiography and GDMT in patients with moderate-severe ischemia will formally test this hypothesis. The current review will highlight the available evidence including a review of the published and ongoing SIHD trials.

BACKGROUND: Exercise treadmill stress myocardial perfusion imaging (MPI) with single photon emission computed tomography is commonly used to evaluate the extent and severity of inducible ischemia as well as to risk stratify patients with suspected and known coronary artery disease (CAD). Failure to reach adequate stress, defined as not attaining age-appropriate metabolic equivalents (METs), can underestimate the extent and severity of ischemic heart disease, resulting in false negative results. This study evaluates the efficacy of the Duke Activity Status Index (DASI), a simple self-administered 12-item questionnaire, as a predictor of METs achieved by treadmill stress testing. METHODS: The DASI was prospectively administered to 200 randomly selected men and women referred to the nuclear cardiology laboratory at New York University Langone Medical Center for stress MPI. Each patient was asked to complete the 12-item DASI questionnaire independently. 136 patients underwent treadmill exercise with MPI and 64 had pharmacologic stress with MPI. The association between exercise capacity in METs as estimated by the DASI questionnaire and performance on the Bruce treadmill protocol in METS was compared using chi-square statistics. RESULTS: Over 70% of those patients whose DASI score predicted the ability to perform <10 METs were unable to exercise beyond stage 2 of the Bruce protocol (7 METs). For those whose DASI score predicted ability to perform >12.5 METs, over 80% of patients reached >stage 2 of the Bruce protocol with 40% reaching beyond stage 3 (10 METs). When patient age was incorporated into the calculation, a more linear relationship was observed between predicted and obtained METs. CONCLUSION: The DASI is a simple self-administered questionnaire which is a useful pretest tool to determine a patient's ability to achieve appropriate METs. In the nuclear cardiology laboratory, the DASI has the potential to guide selection of exercise treadmill vs pharmacologic stress and ultimately improve laboratory efficiency

BACKGROUND: Filtered back-projection (FBP) has been a standard in SPECT imaging. Newer iterative reconstruction algorithms have been shown to improve image quality and shorten acquisition time by taking into account statistical nature of raw data and using resolution recovery (RR). Wide-beam reconstruction (WBR) is an iterative algorithm with RR and adaptive noise control. We prospectively investigated outcome of WBR half-time SPECT on diagnostic certainty, accuracy and normalcy by quantitative perfusion analysis in comparison to full-time FBP images. METHODS: 434 patients underwent rest (201)Tl/stress (99m)Tc-sestamibi full-time (20 s/stop, FBP) followed by a half-time (10 s/stop, WBR) SPECT. 34 patients underwent an angiogram within 90 days of SPECT. Diagnostic certainty was based on summed stress scores (SSS, 5-point/17 segments): normal if SSS </= 1, equivocal if SSS = 2-3, and abnormal if SSS >/= 4. Perfusion defects were normalized to a percent of total myocardium, and expressed as %LV = defect SSS/maximal SSS x 100% with maximal SSS of 28 for left anterior descending (LAD), and of 20 for right coronary (RCA) and left circumflex (LCX). Change in %LV (Delta%LV = %LV F

Objectives. Determine outcome of the 2005 appropriateness use criteria (AUC) for SPECT in a diverse population of patients and physicians. Background. AUC for SPECT were the first cardiology document to identify 52 clinical indications for imaging, 49 of them for stress SPECT. AUC have been proposed as cornerstone of responsible use of perfusion imaging. Methods. 585 consecutive patients undergoing SPECT were evaluated prospectively. Appropriateness was examined for demographic variables, clinical variables, and for physician and patient subgroups. Combined end-point of total mortality, cardiac revascularization, and cardiac admissions at 1 year post SPECT was evaluated. Results. SPECT indications were: appropriate, 63%; uncertain, 20%; inappropriate, 14%; not assigned, 3%. Most appropriate SPECT were observed in patients with known coronary disease (72%), chest pain syndrome (89%), high pre-test likelihood of disease (100%), men (70%), inpatients (72%), and cardiovascular physicians' referrals (69%). End-point was reached in 53 patients (97.4% follow up). Unadjusted event rates were: appropriate (12%), uncertain (7.1%), inappropriate (2.4%) SPECT (P = .01). Conclusion. Appropriateness of SPECT differs in subgroups of patients and physicians. Clinically significant outcomes occur more frequently in the appropriate stress SPECT group. Focused efforts are need for outpatients, asymptomatic patients, women, and non-cardiovascular physicians.

Significant progress in research has been made in the areas of sex-specific aspects of cardiovascular disease. Despite these advances, coronary artery disease (CAD) is the leading cause of death of women in the Western world. Over the past decade, the focused research on women at risk for ischemic heart disease has helped to clarify our understanding of some of the sex-specific factors, which are important in detecting CAD. In women, the detection and evaluation of physiologically significant CAD is challenging, especially given that traditional tests designed to detect focal areas of coronary artery stenosis are less sensitive and specific in female patients who have a lower prevalence of obstructive coronary disease, greater burden of symptoms, and a high atherosclerotic burden. In this article, we review the available evidence on the role of contemporary cardiovascular imaging techniques in evaluating ischemic heart disease in women

INTRODUCTION: Revascularization is an important strategy for reducing stroke risk in patients with severe carotid atherosclerosis. Magnetic resonance angiography (MRA) and/or carotid ultrasound have traditionally been used as the only diagnostic modalities prior to revascularization. Patients undergoing CEA frequently have no further assessments of carotid anatomy prior to surgery. Evaluation with carotid ultrasound and MRA can often overestimate the degree of stenosis. We sought to determine if noninvasive imaging was sufficient for determining whether a patient should be referred for carotid intervention. METHODS: We performed an analysis of 101 patients referred for carotid artery stenting (CAS). All patients had previously been evaluated with carotid ultrasound and 94% had undergone MRA as well. We sought to determine if noninvasive diagnostic imaging for carotid stenosis was sufficient to determine the necessity for endovascular intervention. RESULTS: Of the 101 patients referred for carotid intervention, 36 (36%) were shown to have <70% stenoses and did not require intervention. Of those who had significant disease, 49 (75%) underwent successful CAS, 15 (23%) underwent CEA, and 1 patient was treated medically for a total occlusion. Three of the 36 patients not requiring carotid intervention were found to have subclavian stenosis. Two (4%) of the patients undergoing CAS and 4 (27%) of the patients undergoing CEA had minor complications. No patients suffered a major stroke, MI, or death at follow-up. CONCLUSION: This analysis demonstrates that 36% of patients referred for endovascular intervention based on noninvasive imaging did not meet criteria by angiography. This emphasizes the need for carotid angiography prior to carotid intervention