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This document is an update to the 2013 publication of the Society for Cardiovascular Magnetic Resonance (SCMR) Board of Trustees Task Force on Standardized Protocols. Concurrent with this publication, 3 additional task forces will publish documents that should be referred to in conjunction with the present document. The first is a document on the Clinical Indications for CMR, an update of the 2004 document. The second task force will be updating the document on Reporting published by that SCMR Task Force in 2010. The 3rd task force will be updating the 2013 document on Post-Processing. All protocols relative to congenital heart disease are covered in a separate document. The section on general principles and techniques has been expanded as more of the techniques common to CMR have been standardized. A section on imaging in patients with devices has been added as this is increasingly seen in day-to-day clinical practice. The authors hope that this document continues to standardize and simplify the patient-based approach to clinical CMR. It will be updated at regular intervals as the field of CMR advances. [ABSTRACT FROM AUTHOR]

[Display omitted] [ABSTRACT FROM AUTHOR]

The global burden of peripheral artery disease (PAD) is significant. This has led to numerous recent advances in magnetic resonance imaging (MRI) techniques in PAD. Older techniques such as time of flight MRI or phase contrast MRI are burdened by long acquisition times and significant issues with artifacts. In addition, the most used MRI modality, contrast-enhanced MR angiography (CE-MRA) is limited by the use of gadolinium contrast and its potential toxicity. Novel MRI techniques such as arterial spin labeling (ASL), blood-oxygen-level dependent imaging (BOLD), and first-pass perfusion gadolinium enhancement are advancing the field by providing skeletal muscle perfusion/oxygenation data while maintaining excellent spatial and temporal resolution. Perfusion data can be critical to providing objective clinical data of a visualized stenosis. In addition, there are a number of new MRI sequences assessing plaque composition and lesion severity in the absence of contrast. These approaches used in combination can provide useful clinical and prognostic data and provide critical endpoints in PAD research. [ABSTRACT FROM AUTHOR]

This document is an update to the 2008 publication of the Society for Cardiovascular Magnetic Resonance (SCMR) Board of Trustees Task Force on Standardized Protocols. Since the time of the original publication, 3 additional task forces (Reporting, Post-Processing, and Congenital Heart Disease) have published documents that should be referred to in conjunction with the present document. The section on general principles and techniques has been expanded as more of the techniques common to CMR have been standardized. There is still a great deal of development in the area of tissue characterization/mapping, so these protocols have been in general left as optional. The authors hope that this document continues to standardize and simplify the patient-based approach to clinical CMR. It will be updated at regular intervals as the field of CMR advances. [ABSTRACT FROM AUTHOR]

Parallel tracks for clinical scientists, basic scientists, and pediatric imagers was the novel approach taken for the highly successful 8th Annual Scientific Sessions of the Society for Cardiovascular Magnetic Resonance, held in San Francisco, California, January 21 to 23, 2005. Attendees were immersed in information on the latest scientific advances in cardiovascular magnetic resonance (CMR) from mice to man and technological advances from systems with field strengths from 0.5 T to 11.7 T. State-of-the-art applications were reviewed, spanning a wide range from molecular imaging to predicting outcome with CMR in large patient populations. [Copyright &y& Elsevier]

Aficamten, a next-in-class cardiac myosin inhibitor, improved peak oxygen uptake (pVO 2) and lowered resting and Valsalva left ventricular outflow (LVOT) gradients in adults with symptomatic obstructive hypertrophic cardiomyopathy (oHCM) in SEQUOIA-HCM (Phase 3 Trial to Evaluate the Efficacy and Safety of Aficamten Compared to Placebo in Adults With Symptomatic oHCM), a phase 3, multicenter, randomized, double-blinded, placebo-controlled study. The authors sought to evaluate the effect of aficamten on echocardiographic measures of cardiac structure and function in SEQUOIA-HCM. Serial echocardiograms were performed over 28 weeks in patients randomized to receive placebo or aficamten in up to 4 individually titrated escalating doses (5-20 mg daily) over 24 weeks based on Valsalva LVOT gradients and left ventricular ejection fraction (LVEF). Among 282 patients (mean age 59 ± 13 years; 41% female, 79% White, 19% Asian), mean LVEF was 75% ± 6% with resting and Valsalva LVOT gradients of 55 ± 30 mm Hg and 83 ± 32 mm Hg, respectively. Over 24 weeks, aficamten significantly lowered resting and Valsalva LVOT gradients, and improved left atrial volume index, lateral and septal eʹ velocities, and lateral and septal E/eʹ (all P ≤ 0.001). LV end-systolic volume increased and wall thickness decreased (all P ≤ 0.003). Aficamten resulted in a mild reversible decrease in LVEF (−4.8% [95% CI: −6.4% to −3.3%]; P < 0.001) and absolute LV global circumferential strain (−3.7% [95% CI: 1.8%-5.6%]; P < 0.0010), whereas LV global longitudinal strain was unchanged. Several measures, including LVEF, LVOT gradients, and E/eʹ returned to baseline following washout. Among those treated with aficamten, improved pVO 2 and reduction in N-terminal pro–B-type natriuretic peptide (NT-proBNP) were associated with improvement in lateral eʹ velocity and septal and lateral E/eʹ (all P < 0.03), whereas improvement in Kansas City Cardiomyopathy Questionnaire Clinical Summary Scores (KCCQ-CSS) was associated with a decrease in both LVOT gradients (all P < 0.001). Compared with placebo, patients receiving aficamten demonstrated significant improvement in LVOT gradients and measures of LV diastolic function, and several of these measures were associated with improvements in pVO 2 , KCCQ-CSS, and NT-proBNP. A modest decrease in LVEF occurred yet remained within normal range. These findings suggest aficamten improved multiple structural and physiological parameters in oHCM without significant adverse changes in LV systolic function. (Phase 3 Trial to Evaluate the Efficacy and Safety of Aficamten Compared to Placebo in Adults With Symptomatic oHCM [SEQUOIA-HCM]; NCT05186818) [ABSTRACT FROM AUTHOR]

Presents information on a study which hypothesized that beta-blockade added to angiotensin-converting enzyme inhibition during left ventricular remodeling after myocardial infarction would preserve regional function in adjacent regions. Methodology of the study; Results and discussion.

Examines the effect of beta-blockade on left ventricular (LV) remodeling when added to angiotensin-converting enzyme inhibition after anterior myocardial infarction (MI). Characterization of LV remodeling after large MI; Lowering of heart rate; Improvement of ejection fraction; Effect of beta-blockade on blood pressure, LV mass and cavity size.

Investigates the dose-dependent response to incremental dobutamine in the normal human left ventricle through rapid magnetic resonance imaging (MRI) myocardial tagging. Absence of adverse effects related to dobutamine infusion; Hemodynamic response to dobutamine infusion; Circumferential heterogeneity in end-systolic percent circumferential shortening.

Examines the usefulness of magnetic resonance imaging in providing a comprehensive evaluation of post-myocardial infarction patients. Clinical profile of patients; Parameters of myocardial viability; Left ventricular structure and global function; Infarct artery patency.

Introduction: The Hypertrophic Cardiomyopathy Registry (HCMR) is a NHLBI-funded study of 2764 HCM patients recruited from 44 sites worldwide. Baseline clinical evaluation included echo, cardiac magnetic resonance imaging (CMR), and blood drawn for genetic and biomarker analysis. Follow-up is 1.5 years to date. CMR protocol included short axis cines, pre-and post-contrast T1 mapping, and late gadolinium enhancement (LGE). Hypothesis: We hypothesized that demographic factors may relate to extent of LGE (replacement fibrosis) and T1 mapping (interstitial fibrosis). Methods: LGE assessed visually was categorized as none, >0-5, >5-10, >10-15 and >15% of LV mass. LGE relationship to continuous demographic variables was assessed by one-way analysis of variance. The relationship of native T1 (by field strength) and extracellular volume (ECV) with baseline variables were assessed by Pearson correlations, unpaired t-tests, or analysis of variance. Results: Of 2764 patients, 2556 (92%) had valid LGE values and 50% had any LGE. (Table) Only 2% of patients had LGE >15% of LV mass. Age was similar across LGE categories, but BMI declined with greater LGE extent. There were smaller % of whites and blacks with >15% LGE, but a larger % of other races (primarily Asian). With more LGE, a family history of HCM was more likely and hypertension less likely. The greater the LGE extent, the lower the LVEF. 2122 patients (77%) had valid native T1 and 1988 (72%) valid ECV measures. There was no relationship between age, BMI, or race with either T1 or ECV. Females had longer native T1 at 1.5T (p < 0.001), but not at 3T (p = 0.168). Females had higher ECV values (0.32±0.06 vs. 0.30±0.06, p<0.001). Conclusions: Baseline data from HCMR demonstrate that 2% of patients have LGE >15% of LV mass. These patients have more family history of HCM, are less often black or white, have less hypertension, lower BMI, and lower LVEF. These data suggest that extensive LGE, a risk factor for sudden cardiac death, may be more typical of familial, rather than sporadic or secondary disease. Ongoing genetic analysis may shed additional light. Interstitial fibrosis is greater in females with HCM. Longer follow-up is needed to demonstrate whether these baseline findings are associated with adverse cardiovascular outcome. [ABSTRACT FROM AUTHOR]

The author compares the effects of coronary computed tomographic angiography and those of functional stress testing with exercise electrocardiography, stress echocardiography and nuclear stress testing, on cardiovascular outcomes. Topics discussed include the National Heart, Lung and Blood Institute-supported Prospective Multicenter Imaging Study for Evaluation of Chest Pain and the International Study of Comparative Health Effectiveness with Medical and Invasive Approaches.

An abstract of the article "DANTE preparation for black-blood coronary wall imaging," by Meihan Wang, Christopher M. Kramer and Craig H. Meyer is presented.

Extensive atherosclerotic plaque burden in the lower extremities often leads to symptomatic peripheral artery disease (PAD) including impaired walking performance and claudication. Interleukin-1β (IL-1β) may play an important pro-inflammatory role in the pathogenesis of this disease. Interruption of IL-1β signaling was hypothesized to decrease plaque progression in the leg macrovasculature and improve the mobility of patients with PAD with intermittent claudication. Thirty-eight patients (mean age 65 years; 71% male) with symptomatic PAD (confirmed by ankle–brachial index) were randomized 1:1 to receive canakinumab (150 mg subcutaneously) or placebo monthly for up to 12 months. The mean vessel wall area (by 3.0 T black-blood magnetic resonance imaging (MRI)) of the superficial femoral artery (SFA) was used to measure plaque volume. Mobility was assessed using the 6-minute walk test. Canakinumab was safe and well tolerated. Markers of systemic inflammation (interleukin-6 and high-sensitivity C-reactive protein) fell as early as 1 month after treatment. MRI (32 patients at 3 months; 21 patients at 12 months) showed no evidence of plaque progression in the SFA in either placebo-treated or canakinumab-treated patients. Although an exploratory endpoint, placebo-adjusted maximum and pain-free walking distance (58 m) improved as early as 3 months after treatment with canakinumab when compared with placebo. Although canakinumab did not alter plaque progression in the SFA, there is an early signal that it may improve maximum and pain-free walking distance in patients with symptomatic PAD. Larger studies aimed at this endpoint will be required to definitively demonstrate this. ClinicalTrials.gov Identifier: NCT01731990 [ABSTRACT FROM AUTHOR]

An abstract of the conference paper "Quantitative first-pass MRI measures increased myocardial perfusion after vasodilation in mice," by Brent A. French, and colleagues is presented.

The article presents the author's views on the Society for Cardiovascular Magnetic Resonance (SCMR). According to the author, activity is high within many of the committees of the SCMR. The author states that the society is healthy in terms of financial standing and membership. The author opines that the total assets of the society are up by 17% during the world-wide recession.

GadaCAD2 was 1 of 2 international, multicenter, prospective, Phase 3 clinical trials that led to U.S. Food and Drug Administration approval of gadobutrol to assess myocardial perfusion and late gadolinium enhancement (LGE) in adults with known or suspected coronary artery disease (CAD). A prespecified secondary objective was to determine if stress perfusion cardiovascular magnetic resonance (CMR) was noninferior to single-photon emission computed tomography (SPECT) for detecting significant CAD and for excluding significant CAD. Participants with known or suspected CAD underwent a research rest and stress perfusion CMR that was compared with a gated SPECT performed using standard clinical protocols. For CMR, adenosine or regadenoson served as vasodilators. The total dose of gadobutrol was 0.1 mmol/kg body weight. The standard of reference was a 70% stenosis defined by quantitative coronary angiography (QCA). A negative coronary computed tomography angiography could exclude CAD. Analysis was per patient. CMR, SPECT, and QCA were evaluated by independent central core lab readers blinded to clinical information. Participants were predominantly male (61.4% male; mean age 58.9 ± 10.2 years) and were recruited from the United States (75.0%), Australia (14.7%), Singapore (5.7%), and Canada (4.6%). The prevalence of significant CAD was 24.5% (n = 72 of 294). Stress perfusion CMR was statistically superior to gated SPECT for specificity (P = 0.002), area under the receiver operating characteristic curve (P < 0.001), accuracy (P = 0.003), positive predictive value (P < 0.001), and negative predictive value (P = 0.041). The sensitivity of CMR for a 70% QCA stenosis was noninferior and nonsuperior to gated SPECT. Vasodilator stress perfusion CMR, as performed with gadobutrol 0.1 mmol/kg body weight, had superior diagnostic accuracy for diagnosis and exclusion of significant CAD vs gated SPECT. [Display omitted] [ABSTRACT FROM AUTHOR]

Background: The distal superficial femoral artery (SFA) is most commonly affected in peripheral artery disease (PAD). The effects of the proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitor alirocumab added to statin therapy on SFA atherosclerosis, downstream flow, and walking performance are unknown. Methods: Thirty-five patients with PAD on maximally tolerated statin therapy were recruited. Patients were randomized to alirocumab 150 mg subcutaneously (n = 18) or matching placebo (n = 17) therapy every 2 weeks for 1 year. The primary outcome was change in SFA plaque volume by black blood magnetic resonance imaging (MRI). Secondary outcomes were changes in calf muscle perfusion by cuff/occlusion hyperemia arterial spin labeling MRI, 6-minute walk distance (6MWD), low-density lipoprotein (LDL) cholesterol, and other biomarkers. Results: Age (mean ± SD) was 64 ± 8 years, 20 (57%) patients were women, 17 (49%) were Black individuals, LDL was 107 ± 36 mg/dL, and the ankle–brachial index 0.71 ± 0.20. The LDL fell more with alirocumab than placebo (mean [95% CI]) (−49.8 [−66.1 to −33.6] vs −7.7 [−19.7 to 4.3] mg/dL; p < 0.0001). Changes in SFA plaque volume and calf perfusion showed no difference between groups when adjusted for baseline (+0.25 [−0.29 to 0.79] vs −0.04 [−0.47 to 0.38] cm3; p = 0.37 and 0.22 [−8.67 to 9.11] vs 3.81 [−1.45 to 9.08] mL/min/100 g; p = 0.46, respectively), nor did 6MWD. Conclusion: In this exploratory study, the addition of alirocumab therapy to statins did not alter SFA plaque volume, calf perfusion or 6MWD despite significant LDL lowering. Larger studies with longer follow up that include plaque characterization may improve understanding of the effects of intensive LDL-lowering therapy in PAD (ClinicalTrials.gov Identifier: NCT02959047). [ABSTRACT FROM AUTHOR]

Atherosclerotic plaque stability depends on 3 factors: (1) lipid core, (2) fibrous cap and its thickness, and (3) inflammation within the cap. Magnetic resonance imaging (MRI) is a noninvasive technique that can provide information on these plaque components using a variety of pulse sequences. Assessment of plaque volume and tissue components and the efficacy of lipid-lowering therapy has been performed in human aorta and carotid arteries. Imaging the coronary wall for plaque burden is a novel application of MRI. Newer approaches also include intravascular and transesophageal MRI techniques. Several emerging MR contrast agents being tested in animal models hold promise for targeted imaging of plaque. MRI is a powerful noninvasive imaging tool with high spatial resolution that continues to prove its value in determining atherosclerotic plaque volume and tissue components. [ABSTRACT FROM AUTHOR]

Left ventricular outflow tract (LVOT) obstruction is a major determinant of heart failure symptoms in obstructive hypertrophic cardiomyopathy (oHCM). Aficamten, a next-in-class cardiac myosin inhibitor, may lower gradients and improve symptoms in these patients. This study aims to evaluate the safety and efficacy of aficamten in patients with oHCM. Patients with oHCM and LVOT gradients ≥30 mm Hg at rest or ≥50 mm Hg with Valsalva were randomized 2:1 to receive aficamten (n = 28) or placebo (n = 13) in 2 dose-finding cohorts. Doses were titrated based on gradients and ejection fraction (EF). Safety and changes in gradient, EF, New York Heart Association functional class, and cardiac biomarkers were assessed over a 10-week treatment period and after a 2-week washout. From baseline to 10 weeks, aficamten reduced gradients at rest (mean difference: −40 ± 27 mm Hg, and −43 ± 37 mm Hg in Cohorts 1 and 2, P = 0.0003 and P = 0.0004 vs placebo, respectively) and with Valsalva (−36 ± 27 mm Hg and −53 ± 44 mm Hg, P = 0.001 and <0.0001 vs placebo, respectively). There were modest reductions in EF (−6% ± 7.5% and −12% ± 5.9%, P = 0.007 and P < 0.0001 vs placebo, respectively). Symptomatic improvement in ≥1 New York Heart Association functional class was observed in 31% on placebo, and 43% and 64% on aficamten in Cohorts 1 and 2, respectively (nonsignificant). With aficamten, N-terminal pro–B-type natriuretic peptide was reduced (62% relative to placebo, P = 0.0002). There were no treatment interruptions and adverse events were similar between treatment arms. Aficamten resulted in substantial reductions in LVOT gradients with most patients experiencing improvement in biomarkers and symptoms. These results highlight the potential of sarcomere-targeted therapy for treatment of oHCM. [Display omitted] [ABSTRACT FROM AUTHOR]

Cardiac magnetic resonance (CMR) is considered the gold standard for the assessment of right ventricular ejection fraction (RVEF). Previous studies have suggested that RVEF may be a predictor of adverse outcomes in heart failure (HF). In this study, we aimed to systematically review the prognostic value of RVEF, evaluated by CMR, across the spectrum of left ventricular systolic function in patients with HF. Electronic databases were searched for studies investigating the prognostic value of RVEF in HF, irrespective of left ventricular ejection fraction (LVEF). A random-effects meta-analysis was conducted for mortality and HF hospitalization. Subgroup analyses were also performed based on the presence of reduced (<50%) or preserved LVEF (≥50%). In total, 46 studies enrolling 14,344 patients were included. In the pooled analyses, impaired RVEF was a powerful predictor of mortality (HR: 1.26, 95% CI: 1.18–1.33, I2: 13%, per 10% decrease in RVEF) and death or HF hospitalization (HR: 1.31, 95% Cl: 1.2–1.42, I2: 27%, per 10% decrease in RVEF). A decrease in RVEF was strongly associated with increased risk of mortality or hospitalization both in HF with reduced EF (HR: 1.24, 95% CI: 1.13–1.36, I2: 2%, per 10% decrease in RVEF) and in HF with preserved EF (HR: 1.24, 95% CI: 1.09–1.40, I2: 0%, per 10% decrease in RVEF). Impaired RVEF on CMR strongly predicts adverse outcomes in patients with HF regardless of LVEF. RV systolic function should be carefully evaluated in these patients. Prospero Registration: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021256967 • Impaired RVEF on CMR strongly predicts adverse outcomes (i.e. death, HF hospitalization) in patients with HF, regardless of LVEF • Impaired RVEF on CMR is a strong predictor of mortality in both ischemic and non-ischemic cardiomyopathy • RV systolic function should be carefully evaluated and thoroughly reported in patients with HF, especially during a CMR exam. [ABSTRACT FROM AUTHOR]

The article presents the guidelines provided by the Society for Cardiovascular Magnetic Resonance (SCMR) for the reporting of the results of cardiovascular magnetic resonance (CMR) examinations. Topics include the key components of the report like patient demographics, site and equipment information and cardiovascular imaging features, and the importance of effective communication in a diagnostic imaging procedure.

Within cardiomyocytes, endothelial nitric oxide synthase (eNOS) and neuronal nitric oxide synthase (nNOS) are thought to modulate L-type calcium channel (LTCC) function and sarcoplasmic reticulum calcium cycling, respectively. However, divergent results from mostly invasive prior studies suggest more complex roles. To elucidate the roles of nNOS and eNOS in vivo, we applied noninvasive cardiac MRI to study wild-type (WT), eNOS-/-, and nNOS-/- mice. An in vivo index of LTCC flux (LTCCI) was measured at baseline (Bsl), dobutamine (Dob), and dobutamine + carbacholamine (Dob + CCh) using manganese-enhanced MRI. Displacement-encoded MRI assessed contractile function by measuring circumferential strain (Ecc) and systolic (dEcc/dt) and diastolic (dEcc/dtdiastolic) strain rates at Bsl, Dob, and Dob + CCh. Bsl LTCCI was highest in nNOS-/- mice (P < 0.05 vs. WT and eNOS-/-) and increased only in WT and eNOS-/- mice with Dob (P < 0.05 vs. Bsl). LTCCI decreased significantly from Dob levels with Dob + CCh in all mice. Contractile function, as assessed by Ecc, was similar in all mice at Bsl. With Dob, Ecc increased significantly in WT and eNOS-/- but not nNOS-/- mice (P < 0.05 vs. WT and eNOS-/-). With Dob + CCh, Ecc returned to baseline levels in all mice. Systolic blood pressure, measured via tail plethysmography, was highest in eNOS-/- mice (P < 0.05 vs. WT and nNOS-/-). Mice deficient in nNOS demonstrate increased Bsl LTCC function and an attenuated contractile reserve to Dob, whereas eNOS-/- mice demonstrate normal LTCC and contractile function under all conditions. These results suggest that nNOS, not eNOS, plays the dominant role in modulating Ca2+ cycling in the heart. [ABSTRACT FROM AUTHOR]

Image Integration with a Catheter Mapping System. Background: Catheter ablation of atrial and ventricular tachyarrhythmia involves anatomically based cardiac ablation strategies. CT and MRI images provide the most detailed cardiac anatomy available. Integration of these images into a mapping system should produce detailed and accurate models suitable to guide ablation. Objective: The purpose of this study was to validate and assess the accuracy of a novel CT and MRI image integration algorithm designed to facilitate catheter navigation and ablation. Methods: Using a lateral thoracotomy, markers were sutured to the epicardial surface of each cardiac chamber in 12 swine. Detailed CT/MRI anatomy was imported into the mapping system. The CT/MRI image was then integrated with a detailed catheter geometry of the relevant chamber using a new image integration algorithm. The epicardial markers, identified from the CT/MRI images, were then displayed on the surface of the integrated image. Guided only by the integrated CT/MRI, a single RF lesion was directed at the corresponding endocardial site for each epicardial marker. At autopsy, the distance from the endocardial RF lesion to the target site was assessed. Results: The mean position error (CT/MRI) for the left atrium was 2.5 ± 2.4 mm/5.1 ± 3.9 mm, for the right atrium 6.2 ± 6.5 mm/4.3 ± 2.2 mm, for the right ventricle 6.2 ± 4.3 mm/6.6 ± 5.3 mm, and for the left ventricle 4.7 ± 3.4 mm/3.1 ± 2.7 mm. There was no cardiac perforation or tamponade. Conclusion: CT and MRI images can be effectively utilized for catheter navigation when integrated into a mapping system. This novel registration module with dynamic registration provides effective guidance for ablation. (J Cardiovasc Electrophysiol, Vol. 21, pp. 81–87, January 2010) [ABSTRACT FROM AUTHOR]