Rami Doukky

Impact of Appropriate Use on the Prognostic Value of Single-Photon Emission Computed Tomography Myocardial Perfusion Imaging

Background —Appropriate use criteria (AUC) have been developed to aid in the optimal use of SPECT-myocardial perfusion imaging (MPI), a technique that is a mainstay of risk-assessment for ischemic heart disease. The impact of appropriate use on the prognostic value of SPECT-MPI is unknown. Methods and Results —A prospective cohort-study of 1511 consecutive patients undergoing outpatient, community-based SPECT-MPI was conducted. Subjects were stratified based on the 2009 AUC for SPECT-MPI into appropriate or uncertain appropriateness group and inappropriate group. Patients were prospectively followed for 27±10 months for major adverse cardiac events (MACE) of death, death or myocardial infarction (MI), and cardiac death or MI. In the entire cohort, the 167 (11%) subjects with abnormal scan expectedly experienced significantly higher rates of MACE and coronary revascularization than those with normal MPI. Among the 823 (54.5%) subjects whose MPIs were classified as appropriate [779 (51.6%)] or uncertain [44(2.9%)], abnormal scan predicted a multi-fold increase in the rates of death [9.2% vs. 2.6%;HR=3.1; P =0.004], death or MI [11.8% vs. 3.3%;HR=3.3; P =0.001], cardiac death or MI [6.7% vs. 1.7%;HR=3.7; P =0.006], and revascularization [24.7% vs. 2.7%;HR=11.4; P <0.001]. However, among the 688 (45.5%) subjects with MPI classified as inappropriate, abnormal MPI failed to predict MACE, although was associated with a high revascularization rate. Furthermore, appropriate MPI use provided an incremental prognostic value beyond myocardial perfusion and ejection fraction data. Conclusions —When performed for appropriate indications, SPECT-MPI continues to demonstrate high prognostic value. However, inappropriate use lacks effectiveness for risk-stratification, further emphasizing the need for optimal patient selection for cardiac testing.Background— Appropriate use criteria (AUC) have been developed to aid in the optimal use of single-photon emission computed tomography (SPECT)–myocardial perfusion imaging (MPI), a technique that is a mainstay of risk assessment for ischemic heart disease. The impact of appropriate use on the prognostic value of SPECT-MPI is unknown. Methods and Results— A prospective cohort study of 1511 consecutive patients undergoing outpatient, community-based SPECT-MPI was conducted. Subjects were stratified on the basis of the 2009 AUC for SPECT-MPI into an appropriate or uncertain appropriateness group and an inappropriate group. Patients were prospectively followed up for 27±10 months for major adverse cardiac events of death, death or myocardial infarction, and cardiac death or myocardial infarction. In the entire cohort, the 167 subjects (11%) with an abnormal scan experienced significantly higher rates of major adverse cardiac events and coronary revascularization than those with normal MPI. Among the 823 subjects (54.5%) whose MPIs were classified as appropriate (779, 51.6%) or uncertain (44, 2.9%), an abnormal scan predicted a multifold increase in the rates of death (9.2% versus 2.6%; hazard ratio, 3.1; P=0.004), death or myocardial infarction (11.8% versus 3.3%; hazard ratio, 3.3; P=0.001), cardiac death or myocardial infarction (6.7% versus 1.7%; hazard ratio, 3.7; P=0.006), and revascularization (24.7% versus 2.7%; hazard ratio, 11.4; P<0.001). Among the 688 subjects (45.5%) with MPI classified as inappropriate, an abnormal MPI failed to predict major adverse cardiac events, although it was associated with a high revascularization rate. Furthermore, appropriate MPI use provided incremental prognostic value beyond myocardial perfusion and ejection fraction data. Conclusions— When performed for appropriate indications, SPECT-MPI continues to demonstrate high prognostic value. However, inappropriate use lacks effectiveness for risk stratification, further emphasizing the need for optimal patient selection for cardiac testing.

The Impact of Appropriate Use on the Prognostic Value of SPECT Myocardial Perfusion Imaging

Background —Appropriate use criteria (AUC) have been developed to aid in the optimal use of SPECT-myocardial perfusion imaging (MPI), a technique that is a mainstay of risk-assessment for ischemic heart disease. The impact of appropriate use on the prognostic value of SPECT-MPI is unknown. Methods and Results —A prospective cohort-study of 1511 consecutive patients undergoing outpatient, community-based SPECT-MPI was conducted. Subjects were stratified based on the 2009 AUC for SPECT-MPI into appropriate or uncertain appropriateness group and inappropriate group. Patients were prospectively followed for 27±10 months for major adverse cardiac events (MACE) of death, death or myocardial infarction (MI), and cardiac death or MI. In the entire cohort, the 167 (11%) subjects with abnormal scan expectedly experienced significantly higher rates of MACE and coronary revascularization than those with normal MPI. Among the 823 (54.5%) subjects whose MPIs were classified as appropriate [779 (51.6%)] or uncertain [44(2.9%)], abnormal scan predicted a multi-fold increase in the rates of death [9.2% vs. 2.6%;HR=3.1; P =0.004], death or MI [11.8% vs. 3.3%;HR=3.3; P =0.001], cardiac death or MI [6.7% vs. 1.7%;HR=3.7; P =0.006], and revascularization [24.7% vs. 2.7%;HR=11.4; P <0.001]. However, among the 688 (45.5%) subjects with MPI classified as inappropriate, abnormal MPI failed to predict MACE, although was associated with a high revascularization rate. Furthermore, appropriate MPI use provided an incremental prognostic value beyond myocardial perfusion and ejection fraction data. Conclusions —When performed for appropriate indications, SPECT-MPI continues to demonstrate high prognostic value. However, inappropriate use lacks effectiveness for risk-stratification, further emphasizing the need for optimal patient selection for cardiac testing.Background— Appropriate use criteria (AUC) have been developed to aid in the optimal use of single-photon emission computed tomography (SPECT)–myocardial perfusion imaging (MPI), a technique that is a mainstay of risk assessment for ischemic heart disease. The impact of appropriate use on the prognostic value of SPECT-MPI is unknown. Methods and Results— A prospective cohort study of 1511 consecutive patients undergoing outpatient, community-based SPECT-MPI was conducted. Subjects were stratified on the basis of the 2009 AUC for SPECT-MPI into an appropriate or uncertain appropriateness group and an inappropriate group. Patients were prospectively followed up for 27±10 months for major adverse cardiac events of death, death or myocardial infarction, and cardiac death or myocardial infarction. In the entire cohort, the 167 subjects (11%) with an abnormal scan experienced significantly higher rates of major adverse cardiac events and coronary revascularization than those with normal MPI. Among the 823 subjects (54.5%) whose MPIs were classified as appropriate (779, 51.6%) or uncertain (44, 2.9%), an abnormal scan predicted a multifold increase in the rates of death (9.2% versus 2.6%; hazard ratio, 3.1; P=0.004), death or myocardial infarction (11.8% versus 3.3%; hazard ratio, 3.3; P=0.001), cardiac death or myocardial infarction (6.7% versus 1.7%; hazard ratio, 3.7; P=0.006), and revascularization (24.7% versus 2.7%; hazard ratio, 11.4; P<0.001). Among the 688 subjects (45.5%) with MPI classified as inappropriate, an abnormal MPI failed to predict major adverse cardiac events, although it was associated with a high revascularization rate. Furthermore, appropriate MPI use provided incremental prognostic value beyond myocardial perfusion and ejection fraction data. Conclusions— When performed for appropriate indications, SPECT-MPI continues to demonstrate high prognostic value. However, inappropriate use lacks effectiveness for risk stratification, further emphasizing the need for optimal patient selection for cardiac testing.

B-type natriuretic peptide predicts left atrial appendage thrombus in patients with nonvalvular atrial fibrillation.

To investigate whether plasma B‐type Natriuretic peptide (BNP), a surrogate of left ventricular filling pressure (LVFP), is predictive of left atrial appendage thrombus (LAAT) in patients with nonvalvular atrial fibrillation (AF) independent of known clinical risk predictors.

Regadenoson use in patients with chronic obstructive pulmonary disease: the state of current knowledge

Stress testing is challenging in patients with chronic obstructive pulmonary disease (COPD). Functional capacity is generally decreased in this patient population, limiting patients’ ability to achieve physiologic stress through exercise. Additionally, due to emphysematous changes, COPD patients tend to have poor acoustic windows that impair the quality and therefore diagnostic accuracy of stress echocardiography techniques. Pharmacologic stress myocardial perfusion imaging (MPI) testing is also problematic, particularly due to the concern for adenosine-induced bronchoconstriction with conventional vasodilator stress agents. Regadenoson, a selective A2A adenosine receptor agonist, has gained popularity due to its ease of administration and improved patient experience in the general population. The literature describing the experience with regadenoson in COPD patients, though limited, is rapidly growing and reassuring. This review summarizes the pharmacology and clinical application of this novel stress agent and presents the available data on the safety and tolerability of its use in COPD patients.

Cardiac imaging for the assessment of patients being evaluated for kidney or liver transplantation

Abstract Cardiac risk assessment prior to kidney and liver transplantation is controversial. Given the paucity of available organs, selecting appropriate recipients with favorable short- and long-term cardiovascular risk profile is crucial. Using noninvasive cardiac imaging tools to guide cardiovascular risk assessment and management can also be challenging and controversial. In this article, we address the burden of coronary artery disease among kidney and liver transplant candidates and review the literature pertaining to the diagnostic accuracy and the prognostic value of noninvasive cardiac imaging techniques in this population.

ASNC imaging guidelines for nuclear cardiology procedures

The American Society of Nuclear Cardiology (ASNC) published a guideline for the reporting of myocardial perfusion imaging (MPI) in 2009. Over the last eight years there has been significant change in the breadth and depth of nuclear cardiology practice along with significant changes in the landscape of structured reporting. In consideration of this degree of change, it is appropriate that the guideline be updated and expanded to include a broader perspective of nuclear cardiology practice. At the same time, many things have not changed. This includes the fact that the report should provide a basic ‘‘bottom line’’ result to the referring physician and that this result must be clear and concise. This premise was expanded on by the American College of Radiology (ACR) with its development of a reporting and communication guideline with continued recent updates. All these documents emphasized the need for a defined structure containing standardized data elements to facilitate utilization of the complex data contained in an imaging report into the integrated healthcare of the patient through the electronic health record. The structured report is also an integral part to define quality in nuclear cardiology practices. There continues to be interest in the implementation of structured reporting as a mechanism to improve quality and outcomes and to reduce cost in fulfillment of the triple aim.

Impact of Physical Inactivity on Mortality in Patients With Heart Failure.

The impact of physical inactivity on heart failure (HF) mortality is unclear. We analyzed data from the HF Adherence and Retention Trial (HART) which enrolled 902 patients with New York Heart Association class II/III HF, with preserved or reduced ejection fraction, who were followed for 36 months. On the basis of mean self-reported weekly exercise duration, patients were classified into inactive (0 min/week) and active (≥1 min/week) groups and then propensity score matched according to 34 baseline covariates in 1:2 ratio. Sedentary activity was determined according to self-reported daily television screen time (<2, 2 to 4, >4 h/day). The primary outcome was all-cause death. Secondary outcomes were cardiac death and HF hospitalization. There were 196 inactive patients, of whom 171 were propensity matched to 342 active patients. Physical inactivity was associated with greater risk of all-cause death (hazard ratio [HR] 2.01, confidence interval [CI] 1.47 to 3.00; p <0.001) and cardiac death (HR 2.01, CI 1.28 to 3.17; p = 0.002) but no significant difference in HF hospitalization (p = 0.548). Modest exercise (1 to 89 min/week) was associated with a significant reduction in the rate of death (p = 0.003) and cardiac death (p = 0.050). Independent of exercise duration and baseline covariates, television screen time (>4 vs <2 h/day) was associated with all-cause death (HR 1.65, CI 1.10 to 2.48; p = 0.016; incremental chi-square = 6.05; p = 0.049). In conclusion, in patients with symptomatic chronic HF, physical inactivity is associated with higher all-cause and cardiac mortality. Failure to exercise and television screen time are additive in their effects on mortality. Even modest exercise was associated with survival benefit.

The Prognostic Value of Undetectable Highly Sensitive Cardiac Troponin I in Patients With Acute Pulmonary Embolism

BACKGROUND Elevated cardiac troponin levels have been shown to be associated with adverse outcomes in patients with acute pulmonary embolism (PE). However, few data address the management implications of undetectable cardiac troponin I (cTnI) using a highly sensitive assay. We hypothesized that undetectable cTnI predicts very low in-hospital adverse event rates. METHODS In a retrospective cohort study, we classified patients with confirmed acute PE according to cTnI detectability into cTnI+ (≥ 0.012 ng/mL) and cTnI- (< 0.012 ng/mL) groups. The Pulmonary Embolism Severity Index (PESI) was used for clinical risk determination. The primary outcome was a composite of hard events defined as in-hospital death, CPR, or thrombolytic therapy. The secondary outcome was a composite of soft events defined as ICU admission or inferior vena cava filter placement. RESULTS Among 298 consecutive patients with confirmed acute PE, 161 (55%) were cTnI+ and 137 (45%) cTnI-. No deaths occurred in the cTnI- group vs nine (6%) in the cTnI+ group (P = .004). No hard events were observed in the cTnI- group vs 15 (9%) in the cTnI+ group (P < .001). Soft events were observed at a lower rate in the cTnI- group (21[15%] vs 69 [43%], P < .001). Patients in the cTnI- group had a higher survival rate free of hard (P = .001) or soft (P < .001) events, irrespective of clinical risk. Furthermore, cTnI provided incremental prognostic value beyond clinical, ECG, and imaging data (P < .001). CONCLUSIONS Highly sensitive cTnI assay provides an excellent prognostic negative predictive value; thus, it plays a role in identifying candidates for out-of-hospital treatment of acute PE.

Tissue Doppler imaging for diagnosis of coronary artery disease: a systematic review and meta-analysis

Global and regional left ventricular (LV) systolic dysfunction is a marker of coronary artery disease (CAD), which is conventionally assessed using two-dimensional echocardiography. Tissue Doppler imaging (TDI) has emerged as an adjunct tool in the diagnosis of regional wall motion abnormalities from CAD. We performed a systematic review and meta-analysis to assess the efficacy of TDI indices in the diagnosis of CAD. We searched MEDLINE and the Cochrane Library for controlled studies comparing TDI measurements in those with and without CAD as confirmed by coronary angiography. Meta-analyses of mean differences in TDI velocities between these populations were performed. Screening of titles and abstracts followed by full-text screening identified 8 studies. At rest, TDI was associated with a significant decrease in the pooled maximum systolic velocity among CAD patients compared to those without CAD [mean difference (MD): -0.66; 95% confidence interval (CI): -0.98 to −0.34]. There were no significant differences in maximum early and late diastolic velocities. Post-stress, TDI was associated with a significant decrease in maximum early diastolic velocity (MD: -1.91; 95% CI: -2.74 to −1.09) and maximum late diastolic velocity (MD: -1.57; 95% CI: -2.95 to −0.18) among CAD patients compared to those without CAD. There was no significant difference in maximum systolic velocity post-stress. Our results suggest that TDI may have a role in the evaluation of CAD. Future studies should evaluate the incremental value of TDI velocities over LV ejection fraction and two dimensional wall motion analysis in the detection of CAD and assessment of its severity. (Word Count: 249)

Impact of Appropriate Use on the Estimated Radiation Risk to Men and Women Undergoing Radionuclide Myocardial Perfusion Imaging

The impact of appropriate use criteria (AUC) for myocardial perfusion imaging (MPI) with SPECT on the estimated lifetime attributable risk (LAR) of cancer is unknown. Methods: A cohort of 1,511 consecutive patients who underwent clinically indicated 99mTc-setamibi MPI were categorized into appropriate/uncertain (n = 823) versus inappropriate (n = 688) use groups according to the 2009 AUC and were prospectively followed for 27 ± 10 mo. Logistic regression models were used to determine the annualized probability of major adverse cardiac events (MACE) of cardiac death or myocardial infarction and the probability of revascularization within 6 mo of MPI, accounting for relevant covariates. We determined LAR for each subject on the basis of accepted risk estimates. We calculated MPI’s benefit-to-risk ratios, defined by the annualized predicted MACE-to-LAR ratio and the predicted 6-mo-revascularization–to–LAR ratio. Results: During follow-up, there were 22 MACE and 29 6-mo revascularizations. The administered radioactivity and effective radiation doses absorbed were similar between the study groups. Patients with inappropriate MPI had significantly higher LAR (median, 0.08% vs. 0.06%, P < 0.001), lower predicted MACE-to-LAR ratio (median, 1.5 vs. 4.3, P < 0.001), and lower predicted 6-mo-revascularization–to–LAR ratio (median, 5.4 vs. 15.5, P < 0.001). Women had higher LAR (median, 0.08% vs. 0.07%, P < 0.001) and lower predicted MACE-to-LAR ratio (median, 1.9 vs. 3.3, P < 0.001) and 6-mo-revascularization–to–LAR ratio (median, 4.4 vs. 17.5, P < 0.001). However, appropriate/uncertain use negated the difference between men and women in LAR (P = 0.94) and the predicted MACE-to-LAR ratio (P = 0.97). Conclusion: Inappropriate MPI use is associated with excess cancer risk and lower MPI’s benefit-to-risk ratio. Appropriate/uncertain use neutralizes the sex gap in LAR with MPI.