The impact of coronary calcium score as an addition to myocardial perfusion imaging in altering clinical management (ICCAMPA trial).

INTRODUCTION: AIM: Myocardial perfusion imaging (MPI) is a key tool for the identification and risk stratification of patients with coronary artery disease. The use of a coronary calcium score further adds to prognostic data above MPI alone. In this study, our aim was to evaluate the extent to which the use of a coronary artery calcium (CAC) score, when co-reported with MPI, impacts changes in clinical management in patients without a history of coronary artery disease (CAD) undergoing functional imaging. METHODS: This is a multicenter international study which incorporated a standardized questionnaire to evaluate changes in clinician management after MPI results were given with and without the additional information of a CAC score. Calcium scoring on a SPECT-CT system was performed via a semiquantitative Shemesh score (0-12) with a 0-3 score from the left main, left anterior descending, left circumflex, and right coronary arteries. CT of the chest was read independently, and non-coronary findings were reported alongside the CAC score. RESULTS: A total of 281 patients were enrolled across 3 international centers (Brazil, Australia, New Zealand). Of the 281 patients, 133 (47%) had management altered after the clinician was made aware of the CAC score. The impact of the CAC in changing clinical management was significant, particularly in patients with a negative MPI (P < 0.0001), but also in MPI-positive patients (P = 0.0021). The most common management change was the addition or intensification of statin therapy. CONCLUSION: The addition of the CAC component to MPI yielded significant management changes in nearly half of all patients undergoing MPI for suspected CAD. This trend was observed across all centers in the three countries involved and was particularly evident in patient with a negative MPI.

ACCF/ASNC appropriateness criteria for single-photon emission computed tomography myocardial perfusion imaging (SPECT MPI): a report of the American College of Cardiology Foundation Quality Strategic Directions Committee Appropriateness Criteria Working Group and the American Society of Nuclear Cardiology endorsed by the American Heart Association.

Under the auspices of the American College of Cardiology Foundation (ACCF) and the American Society of Nuclear Cardiology (ASNC), an appropriateness review was conducted for radionuclide cardiovascular imaging (RNI), specifically gated single-photon emission computed tomography myocardial perfusion imaging (SPECT MPI). The review assessed the risks and benefits of the imaging test for several indications or clinical scenarios and scored them based on a scale of 1 to 9, where the upper range (7 to 9) implies that the test is generally acceptable and is a reasonable approach, and the lower range (1 to 3) implies that the test is generally not acceptable and is not a reasonable approach. The mid range (4 to 6) implies that the test may be generally acceptable and may be a reasonable approach for the indication. The indications for this review were primarily drawn from existing clinical practice guidelines and modified based on discussion by the ACCF Appropriateness Criteria Working Group and the Technical Panel members who rated the indications. The method for this review was based on the RAND/UCLA approach for evaluating appropriateness, which blends scientific evidence and practice experience. A modified Delphi technique was used to obtain first- and second-round ratings of 52 clinical indications. The ratings were done by a Technical Panel with diverse membership, including nuclear cardiologists, referring physicians (including an echocardiographer), health services researchers, and a payer (chief medical officer). These results are expected to have a significant impact on physician decision making and performance, reimbursement policy, and future research directions. Periodic assessment and updating of criteria will be undertaken as needed.

Critical pathway for an aggressive diagnostic strategy for patients who present with chest pain but a nondiagnostic electrocardiogram to the emergency department.

BACKGROUND: The prolonged length of stay for patients who seek treatment in the emergency department with chest pain and normal or nondiagnostic electrocardiogram has led to a backlog of patients in the emergency department and the telemetry unit. Correct early management requires risk stratification processes that can effectively separate the majority of these patients into low-risk, low/intermediate-risk, intermediate-risk, and high-risk subsets. METHODS AND RESULTS: Patients who seek treatment in the emergency department with chest pain are risk-stratified into low-risk, low/intermediate-risk, and high-risk categories using a Risk Score to determine who would benefit from immediate exercise stress testing. Nurse-directed exercise stress testing using the Duke Treadmill Score is used to risk-stratify intermediate-risk patients further "on-the-fly". Intermediate-risk Duke Treadmill Score patients are injected during exercise with a Tc-myocardial perfusion agent and undergo a gated single-photon emission computed tomography study. Normal exercise and single-photon emission computed tomography perfusion patients are discharged home. The overall length of stay and 30-day outcomes of these facilitated patients were compared with those of patients treated with a conservative approach using sequential electrocardiograms and cardiac enzymes. Patients who were evaluated using the facilitated approach had a shorter mean length of stay than those using a conservative method, with similar outcomes at 30 days. CONCLUSIONS: A facilitated approach incorporating on-demand nurse-directed early exercise stress testing with the injection of a Tc-myocardial perfusion agent on the fly in intermediate-risk patients is safe and has decreased the backlog of patients in the emergency department and telemetry unit and expedited appropriate treatment of patients with acute chest pain and nondiagnostic electrocardiograms.

An economic analysis of an aggressive diagnostic strategy with single photon emission computed tomography myocardial perfusion imaging and early exercise stress testing in emergency department patients who present with chest pain but nondiagnostic electrocardiograms: Results from a randomized trial.

STUDY OBJECTIVE: Conventional emergency department testing strategies for patients with chest pain often do not provide unequivocal diagnosis of acute coronary syndromes. This study was conducted to determine whether the routine use of single photon emission computed tomography (SPECT) imaging at rest and early exercise stress testing to assess intermediate-risk patients with chest pain and no ECG evidence of acute ischemia will lead to earlier discharges, more discriminate use of coronary angiography, and an overall reduction in average costs of care with no adverse clinical outcomes. METHODS: All patients in this study had technetium 99m tetrofosmin SPECT imaging at rest and were randomly assigned to either a conventional (results of the imaging test blinded to the physician) or perfusion imaging-guided (results of the imaging test unblinded to the physician) strategy. Patients in the conventional arm were treated at their physician's discretion. Patients in the perfusion imaging-guided arm were treated according to a predefined protocol based on SPECT imaging test results: coronary angiography after a positive scan result and exercise treadmill testing after a negative scan result. Study endpoints consisted of total in-hospital costs and length of stay. Hospital costs were calculated using hospital department-specific Medicare cost/charge ratios. Length of stay was calculated as total hospital room days billed (regular and intensive care). RESULTS: We enrolled 46 patients, 9 with acute myocardial infarctions. Patients randomly assigned to the perfusion imaging-guided arm had $1,843 (95% confidence interval [CI] $431 to $6,171) lower median in-hospital costs and 2.0-day (95% CI 1.0 to 3.0 days) shorter median lengths of stay but similar rates of in-hospital and 30-day follow up events as patients in the conventional arm. CONCLUSION: An ED chest pain diagnostic strategy incorporating acute resting 99mTc tetrofosmin SPECT imaging and early exercise stress testing may lead to reduced in-hospital costs and decreased length of stay for patients with acute chest pain and nondiagnostic ECGs. [Stowers SA, Eisenstein EL, Wackers FJTh, Berman DS, Blackshear JL, Jones AD Jr, Szymanski TJ Jr, Lam LC, Simons TA, Natale D, Paige KA, Wagner GS. An economic analysis of an aggressive diagnostic strategy with single photon emission computed tomography myocardial perfusion imaging and early exercise stress testing in emergency department patients who present with chest pain but nondiagnostic electrocardiograms: results from a randomized trial. Ann Emerg Med. January 2000;35:17-25.].