Society for cardiovascular magnetic resonance recommendations for training and competency of CMR technologists.

The Society for Cardiovascular Magnetic Resonance (SCMR) recommendations for training and competency of cardiovascular magnetic resonance (CMR) technologists document will define the knowledge, experiences and skills required for a technologist to be competent in CMR imaging. By providing a framework for CMR training and competency the overarching goal is to promote the performance of high-quality CMR and to foster the increased adoption of CMR into clinical care.

Screening of Potential Cardiac Involvement in Competitive Athletes Recovering From COVID-19: An Expert Consensus Statement.

As our understanding of the complications of coronavirus disease-2019 (COVID-19) evolve, subclinical cardiac pathology such as myocarditis, pericarditis, and right ventricular dysfunction in the absence of significant clinical symptoms represents a concern. The potential implications of these findings in athletes are significant given the concern that exercise, during the acute phase of viral myocarditis, may exacerbate myocardial injury and precipitate malignant ventricular arrhythmias. Such concerns have led to the development and publication of expert consensus documents aimed at providing guidance for the evaluation of athletes after contracting COVID-19 in order to permit safe return to play. Cardiac imaging is at the center of these evaluations. This review seeks to evaluate the current evidence regarding COVID-19-associated cardiovascular disease and how multimodality imaging may be useful in the screening and clinical evaluation of athletes with suspected cardiovascular complications of infection. Guidance is provided with diagnostic "red flags" that raise the suspicion of pathology. Specific emphasis is placed on the unique challenges posed in distinguishing athletic cardiac remodeling from subclinical cardiac disease. The strengths and limitations of different imaging modalities are discussed and an approach to return to play decision making for athletes post-COVID-19, as informed by multimodality imaging, is provided.

Society for Cardiovascular Magnetic Resonance (SCMR) guidance for the practice of cardiovascular magnetic resonance during the COVID-19 pandemic.

The aim of this document is to provide general guidance and specific recommendations on the practice of cardiovascular magnetic resonance (CMR) in the era of the COVID-19 pandemic. There are two major considerations. First, continued urgent and semi-urgent care for the patients who have no known active COVID-19 should be provided in a safe manner for both patients and staff. Second, when necessary, CMR on patients with confirmed or suspected active COVID-19 should focus on the specific clinical question with an emphasis on myocardial function and tissue characterization while optimizing patient and staff safety.

Prevalence and Prognosis of Unrecognized Myocardial Infarction in Asymptomatic Patients With Diabetes: A Two-Center Study With Up to 5 Years of Follow-up.

OBJECTIVE: To determine the prevalence and prognostic significance of unrecognized myocardial infarction (MI) by delayed-enhancement MRI (DE-MRI) in asymptomatic patients with diabetes. RESEARCH DESIGN AND METHODS: In this prospective, two-center study of asymptomatic patients without known cardiac disease (n = 120), two prespecified cohorts underwent a research MRI: 1) a high-risk group with type 1 diabetes and chronic renal insufficiency (n = 50) and 2) an average-risk group with type 2 diabetes (n = 70). The primary end point was a composite of all-cause mortality and clinical MI. RESULTS: Overall, the prevalence of unrecognized MI was 19% by DE-MRI (28% high-risk group and 13% average-risk group) and 5% by electrocardiography. During up to 5 years of follow-up with a total of 460 patient-years of follow-up, the rate of death/MI was markedly higher in patients with diabetes with (vs. without) unrecognized MI (all 44% vs. 7%, high-risk group 43% vs. 6%, and average-risk group 44% vs. 8%; all P < 0.01). After adjustment for Framingham risk score, left ventricular ejection fraction, and diabetes type, the presence of unrecognized MI by DE-MRI conferred an eightfold increase in risk of death/MI (95% CI 3.0-21.1, P < 0.0001). Addition of unrecognized MI to clinical indices significantly improved model discrimination for adverse events (integrated discrimination improvement = 0.156, P = 0.001). CONCLUSIONS: Unrecognized MI is prevalent in asymptomatic patients with diabetes without a history of cardiac disease and confers a markedly increased risk of death and clinical MI.

Aminophylline shortage and current recommendations for reversal of vasodilator stress: An ASNC information statement endorsed by SCMR.

Pharmacologic reversal of serious or intolerable side effects (SISEs) from vasodilator stress is an important safety and comfort measure for patients experiencing such effects. While typically performed using intravenous aminophylline, recurrent shortages of this agent have led to a greater need to limit its use and consider alternative agents. This information statement provides background and recommendations addressing indications for vasodilator reversal, timing of a reversal agent, incidence of observed SISE with vasodilator stress, clinical and logistical considerations for aminophylline-based reversal, and alternative non-aminophylline based reversal protocols.

Aminophylline shortage and current recommendations for reversal of vasodilator stress: an ASNC information statement endorsed by SCMR.

Pharmacologic reversal of serious or intolerable side effects (SISE) from vasodilator stress is an important safety and comfort measure for patients experiencing such effects. While typically performed using intravenous aminophylline, recurrent shortages of this agent have led to a greater need to limit its use and consider alternative agents. This information statement provides background and recommendations addressing indications for vasodilator reversal, timing of a reversal agent, incidence of observed SISE with vasodilator stress, clinical and logistical considerations for aminophylline-based reversal, and alternative non-aminophylline based reversal protocols.

Detection of myocardial damage in patients with sarcoidosis.

BACKGROUND: In patients with sarcoidosis, sudden death is a leading cause of mortality, which may represent unrecognized cardiac involvement. Delayed-enhancement cardiovascular magnetic resonance (DE-CMR) can detect minute amounts of myocardial damage. We sought to compare DE-CMR with standard clinical evaluation for the identification of cardiac involvement. METHODS AND RESULTS: Eighty-one consecutive patients with biopsy-proven extracardiac sarcoidosis were prospectively recruited for a parallel and masked comparison of cardiac involvement between (1) DE-CMR and (2) standard clinical evaluation with the use of consensus criteria (modified Japanese Ministry of Health [JMH] guidelines). Standard evaluation included 12-lead ECG and at least 1 dedicated non-CMR cardiac study (echocardiography, radionuclide scintigraphy, or cardiac catheterization). Patients were followed for 21+/-8 months for major adverse events (death, defibrillator shock, or pacemaker requirement). Patients were predominantly middle-aged (46+/-11 years), female (62%), and black (73%) and had chronic sarcoidosis (median, 7 years) and preserved left ventricular ejection fraction (median, 56%). DE-CMR identified cardiac involvement in 21 patients (26%) and JMH criteria in 10 (12%, 8 overlapping), a >2-fold higher rate for DE-CMR (P=0.005). All patients with myocardial damage on DE-CMR had coronary disease excluded by x-ray angiography. Pathology evaluation in 15 patients (19%) identified 4 with cardiac sarcoidosis; all 4 were positive by DE-CMR, whereas 2 were JMH positive. On follow-up, 8 had adverse events, including 5 cardiac deaths. Patients with myocardial damage on DE-CMR had a 9-fold higher rate of adverse events and an 11.5-fold higher rate of cardiac death than patients without damage. CONCLUSIONS: In patients with sarcoidosis, DE-CMR is more than twice as sensitive for cardiac involvement as current consensus criteria. Myocardial damage detected by DE-CMR appears to be associated with future adverse events including cardiac death, but events were few, and this needs confirmation in a larger cohort.

Performance of delayed-enhancement magnetic resonance imaging with gadoversetamide contrast for the detection and assessment of myocardial infarction: an international, multicenter, double-blinded, randomized trial.

BACKGROUND: The identification and assessment of myocardial infarction (MI) are important for therapeutic and prognostic purposes, yet current recommended diagnostic strategies have significant limitations. We prospectively tested the performance of delayed-enhancement magnetic resonance imaging (MRI) with gadolinium-based contrast for the detection of MI in an international, multicenter trial. METHODS AND RESULTS: Patients with their first MI were enrolled in an acute (< or = 16 days after MI; n=282) or chronic (17 days to 6 months; n=284) arm and then randomized to 1 of 4 doses of gadoversetamide: 0.05, 0.1, 0.2, or 0.3 mmol/kg. Standard delayed-enhancement MRI was performed before contrast (control) and 10 and 30 minutes after gadoversetamide. For blinded analysis, precontrast and postcontrast MRIs were randomized and then scored for enhanced regions by 3 independent readers not associated with the study. The infarct-related artery perfusion territory was scored from x-ray angiograms separately. In total, 566 scans were performed in 26 centers using commercially available scanners from all major US/European vendors. All scans were included in the analysis. The sensitivity of MRI for detecting MI increased with rising dose of gadoversetamide (P<0.0001), reaching 99% (acute) and 94% (chronic) after contrast compared with 11% before contrast. Likewise, the accuracy of MRI for identifying MI location (compared with infarct-related artery perfusion territory) increased with rising dose of gadoversetamide (P<0.0001), reaching 99% (acute) and 91% (chronic) after contrast compared with 9% before contrast. For gadoversetamide doses > or = 0.2 mmol/kg, 10- and 30-minute images provided equal performance, and peak creatine kinase-MB levels correlated with MRI infarct size (P<0.0001). CONCLUSIONS: Gadoversetamide-enhanced MRI using doses of > or = 0.2 mmol/kg is effective in the detection and assessment of both acute and chronic MI. This study represents the first multicenter trial designed to evaluate an imaging approach for detecting MI.

Rapid detection of myocardial infarction by subsecond, free-breathing delayed contrast-enhancement cardiovascular magnetic resonance.

BACKGROUND: An ultrafast, delayed contrast-enhancement cardiovascular magnetic resonance technique that can acquire subsecond, "snapshot" images during free breathing (subsecond) is becoming widely available. This technique provides myocardial infarction (MI) imaging with complete left ventricular coverage in < 30 seconds. However, the accuracy of this technique is unknown. METHODS AND RESULTS: We prospectively compared subsecond imaging with routine breath-hold delayed contrast-enhancement cardiovascular magnetic resonance (standard) in consecutive patients. Two cohorts with unambiguous standards of truth were prespecified: (1) patients with documented prior MI (n=135) and (2) patients without MI and with low likelihood of coronary disease (lowest Framingham risk category; n=103). Scans were scored masked to identity and clinical information. Sensitivity, specificity, and accuracy of subsecond imaging for MI diagnosis were 87%, 96%, and 91%, respectively. Compared with the standard technique (98%, 100%, 99%), the subsecond technique had modestly reduced sensitivity (P=0.0001), but specificity was excellent. Missed infarcts were generally small or subendocardial (87%). Overall, regional transmural extent of infarction scores were highly concordant (2083/2294; 91%); however, 51 of 337 regions (15%) considered predominantly infarcted (> 50% transmural extent of infarction) by the standard technique were considered viable (< or = 25% transmural extent of infarction) by the subsecond technique. Quantitative analysis demonstrated moderately reduced contrast-to-noise ratios for subsecond imaging between infarct and remote myocardium (12.0+/-7.2 versus 20.1+/-6.6; P<0.0001) and infarct and left ventricular cavity (-2.5+/-2.7 versus 3.6+/-3.7; P<0.0001). CONCLUSIONS: MI can be rapidly detected by subsecond delayed contrast-enhancement cardiovascular magnetic resonance during free breathing with high accuracy. This technique could be considered the preferred approach in patients who are more acutely ill or unable to hold their breath. However, compared with standard imaging, sensitivity is mildly reduced, and the transmural extent of infarction may be underestimated.

Acute myocardial infarction: safety of cardiac MR imaging after percutaneous revascularization with stents.

PURPOSE: To retrospectively determine the safety of cardiac magnetic resonance (MR) imaging performed early (<14 days) after coronary stent implantation in patients with acute myocardial infarction (AMI). MATERIALS AND METHODS: This HIPPA-compliant study was approved by the institutional review board; the informed consent requirement was waived. Consecutive patients with AMI who underwent cardiac MR imaging (study group) shortly after stent implantation (median, 3 days) were compared with control subjects who did not undergo MR imaging and were matched for clinical factors and angiographic extent of coronary disease. A 1.5-T MR imager was used to evaluate cine function, perfusion, and viability. Rates of death, nonfatal myocardial infarction, or revascularization 30 days and 6 months after stent implantation were compared with chi(2) analysis. RESULTS: The study group consisted of 66 patients (median age, 56 years; 17 women) with 97 stents, 38 (39%) of which were drug eluting. The control group included 124 patients (median age, 58 years; 23% women) with 197 stents, 21 (10.7%) of which were drug eluting. There was no significant (P = .13) difference in the combined end point of death, nonfatal myocardial infarction, or revascularization between the study (2.0% [95% confidence interval: 0.0%, 4.5%]) and control (6.5% [95% confidence interval: 1.6%, 11.3%]) groups at 30-day follow-up. The event-free survival rate at 6-month follow-up was 91% in the study group and 83.7% in the control group (P = .18). Considering the end points separately, there was no difference in the event rate at 30-day or 6-month follow-up between groups. No adverse cardiovascular events occurred in patients with drug-eluting stents who underwent MR imaging. CONCLUSION: Cardiac MR imaging performed shortly after AMI and percutaneous revascularization with bare metal or drug-eluting stents appears safe. The risk of adverse cardiovascular events is low and similar to that in patients who do not undergo MR imaging.

Late gadolinium cardiovascular magnetic resonance in the assessment of myocardial viability.

Delayed-enhancement magnetic resonance imaging is a viability imaging technique that has been demonstrated in both animal and patient studies to accurately identify and characterize the presence and transmural extent of myocardial scarring. The precise information regarding the presence, location and extent of myocardial scarring has been shown to be useful in predicting the likelihood of functional recovery of dysfunctional myocardium after revascularization. Perhaps, more importantly, the ability to visualize the extent of viable and nonviable myocardium across the ventricular wall allows one to approach viability as a continuum rather than in a binary manner, providing a better reflection of the underlying physiology.

The impact of adjunctive adenosine infusion during exercise myocardial perfusion imaging: Results of the Both Exercise and Adenosine Stress Test (BEAST) trial.

BACKGROUND: Failure to achieve an adequate heart rate limits the sensitivity of exercise myocardial perfusion imaging (MPI) for the detection of coronary artery disease. In addition, it is often not possible to discontinue medications that may blunt the heart rate response to exercise, because of conditions such as hypertension or angina. However, if pharmacologic stress testing is performed, the ability to assess functional capacity is lost. Accordingly, we developed a protocol that incorporates adenosine stress with symptom-limited exercise. METHODS AND RESULTS: As part of a multicenter study, 35 patients were enrolled prospectively and underwent both exercise MPI and exercise MPI with a 4-minute adenosine infusion on a separate day. Technetium 99m sestamibi was injected at or near peak exercise (exercise only) and at 2 minutes into the adenosine infusion (combined exercise and adenosine). The perfusion images were interpreted in a blinded fashion. The combined adenosine and exercise protocol was well tolerated. The summed stress scores and summed difference scores were greater in the exercise-plus-adenosine group than in the exercise-only group (10.0 vs 8.5, P =.02, and 4.9 vs 3.3, P =.002, respectively). Exercise time was slightly but significantly less with the exercise-plus-adenosine protocol (8 minutes 46 seconds vs 8 minutes 11 seconds, P =.027). CONCLUSION: A protocol combining 4 minutes of adenosine infusion with symptom-limited exercise was safe and well tolerated. Furthermore, this protocol resulted in a greater amount of myocardial ischemia detected on MPI while allowing for the assessment of functional capacity. A combined exercise and adenosine protocol may be a useful test for patients undergoing MPI who are unlikely to achieve an adequate chronotropic response.

Contrast-enhanced MRI and routine single photon emission computed tomography (SPECT) perfusion imaging for detection of subendocardial myocardial infarcts: an imaging study.

BACKGROUND: Myocardial infarcts are routinely detected by nuclear imaging techniques such as single photon emission computed tomography (SPECT) myocardial perfusion imaging. A newly developed technique for infarct detection based on contrast-enhanced cardiovascular magnetic resonance (CMR) has higher spatial resolution than SPECT. We postulated that this technique would detect infarcts missed by SPECT. METHODS: We did contrast-enhanced CMR and SPECT examinations in 91 patients with suspected or known coronary artery disease. All CMR and SPECT images were scored, using a 14-segment model, for the presence, location, and spatial extent of infarction. To compare each imaging modality to a gold standard, we also acquired contrast-enhanced CMR and SPECT images in 12 dogs with, and three dogs without, myocardial infarction as defined by histochemical staining. FINDINGS: In animals, contrast-enhanced CMR and SPECT detected all segments with nearly transmural infarction (>75% transmural extent of the left-ventricular wall). CMR also identified 100 of the 109 segments (92%) with subendocardial infarction (<50% transmural extent of the left-ventricular wall), whereas SPECT identified only 31 (28%). SPECT and CMR showed high specificity for the detection of infarction (97% and 98%, respectively). In patients, all segments with nearly transmural infarction, as defined by contrast-enhanced CMR, were detected by SPECT. However, of the 181 segments with subendocardial infarction, 85 (47%) were not detected by SPECT. On a per patient basis, six (13%) individuals with subendocardial infarcts visible by CMR had no evidence of infarction by SPECT. INTERPRETATION: SPECT and CMR detect transmural myocardial infarcts at similar rates. However, CMR systematically detects subendocardial infarcts that are missed by SPECT.

Myocardial scarring in asymptomatic or mildly symptomatic patients with hypertrophic cardiomyopathy.

OBJECTIVES: We sought to ascertain whether myocardial scarring occurs in living unselected patients with hypertrophic cardiomyopathy (HCM). BACKGROUND: Myocardial scarring is known to occur in select HCM patients, who were highly symptomatic prior to death or who died suddenly. The majority of HCM patients, however, are minimally symptomatic and have not suffered sudden death. METHODS: Cine and gadolinium-enhanced magnetic resonance imaging was performed in 21 HCM patients who were predominantly asymptomatic. Gadolinium hyperenhancement was assumed to represent myocardial scar, and the extent of scar was compared to left ventricular (LV) morphology and function. RESULTS: Scarring was present in 17 patients (81%). Scarring occurred only in hypertrophied regions (> or =10 mm), was patchy with multiple foci, and predominantly involved the middle third of the ventricular wall. All 17 patients had scarring at the junction of the interventricular septum and the right ventricular (RV) free wall. On a regional basis, the extent of scarring correlated positively with wall thickness (r = 0.36, p < 0.0001), and inversely with wall thickening (r = -0.21, p < 0.0001). On a per patient basis, the extent of scarring (mean, 8 +/- 9% of LV mass) was minimally related to maximum wall thickness (r = 0.40, p = 0.07) and LV mass (r = 0.33, p = 0.15), and correlated inversely with ejection fraction (r = -0.46, p = 0.04). CONCLUSIONS: Myocardial scarring is common in asymptomatic or mildly symptomatic HCM patients who have not suffered sudden death. When present, scarring occurs in hypertrophied regions, is consistently localized to the junctions of the septum and RV free wall, and correlates positively with regional hypertrophy and inversely with regional contraction.

Reproducibility of chronic infarct size measurement by contrast-enhanced magnetic resonance imaging.

BACKGROUND: The reproducibility of contrast-enhanced MRI has not been established. We compared MRI reproducibility for infarct size determination with that of (99m)Tc-sestamibi (MIBI) single photon emission computed tomography (SPECT). METHODS AND RESULTS: Patients with chronic myocardial infarction defined by enzymes (peak creatine kinase-MB 173+/-119 U/L) were scanned twice by MRI (MRI I and MRI II, n=20) and twice by SPECT (SPECT I and SPECT II, n=15) on the same day. The MRI contrast agent was injected during MRI I but not MRI II to test the effect of imaging time after contrast. Resting Tc-MIBI SPECT images were acquired and infarct size was determined with commercial software. Infarct size in patients scanned by MRI and SPECT was 14+/-6% of left ventricular mass (%LV) by MRI (range 4%LV to 27%LV) and 14+/-7%LV by SPECT (range 4%LV to 26%LV). MRI I and II scans were performed 10+/-2 and 27+/-3 minutes after contrast, respectively. For MRI, the difference in infarct size between scans I and II (bias) was -0.1%LV, and the coefficient of repeatability was +/-2.4%LV. For SPECT, bias was -1.3%LV, and the coefficient of repeatability was +/-4.0%LV. Within individual patients, no systematic differences in infarct size were detected when the 2 MRI scans were compared, the 2 SPECT scans were compared, or MRI was compared to SPECT. CONCLUSION: The size of healed infarcts measured by contrast-enhanced MRI does not change between 10 and 30 minutes after contrast. The clinical reproducibility of contrast-enhanced MRI for infarct size determination compares favorably with that of routine clinical SPECT.

Technical and immunologic progress in simultaneous pancreas-kidney transplantation.

BACKGROUND: During the past few years the use of new immunosuppressants and refinements in surgical technique of simultaneous pancreas-kidney (SPK) transplantation have resulted in markedly improved outcomes. This is a retrospective study of 208 SPK transplants performed at Northwestern University, demonstrating the advances made at a single center that are reflective of the field at large. METHODS: An 8.5-year time span was split into 4 distinct eras marking sequential changes in immunosuppression and surgical technique that ensued. SPK transplant outcomes of patient and graft survival and rejection rates were compared. Also examined were end points related to the changing risk profile of the recipients, as well as quality of allograft function and rates of rehospitalizations. RESULTS: Recipients receiving tacrolimus/mycophenolate mofetil-based immunosuppression had patient, kidney, and pancreas survival rates significantly higher than those of earlier cohorts. The elimination of corticosteroids did not reduce survival rates or increase rejection risk. The use of pancreatic exocrine enteric drainage technique over bladder drainage reduced rehospitalizations. CONCLUSIONS: Advances in immunosuppression management combined with technical refinements have made SPK transplantation a safer and more effective treatment option for the diabetic, uremic patient.