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Left ventricular (LV) strain measurements can be derived using cardiac MRI from routinely acquired balanced steady-state free precession (bSSFP) cine images.To compare the interfield strength agreement of global systolic strain, peak strain rates and artificial intelligence (AI) landmark-based global longitudinal shortening at 1.5 T and 3 T.Prospective.A total of 22 healthy individuals (mean age 36 ± 12 years; 45% male) completed two cardiac MRI scans at 1.5 T and 3 T in a randomized order within 30 minutes. FIELD STRENGTH/SEQUENCE: bSSFP cine images at 1.5 T and 3 T.Two software packages, Tissue Tracking (cvi42, Circle Cardiovascular Imaging) and QStrain (Medis Suite, Medis Medical Imaging Systems), were used to derive LV global systolic strain in the longitudinal, circumferential and radial directions and peak (systolic, early diastolic, and late diastolic) strain rates. Global longitudinal shortening and mitral annular plane systolic excursion (MAPSE) were measured using an AI deep neural network model.Comparisons between field strengths were performed using Wilcoxon signed-rank test (P value 0.05 considered statistically significant). Agreement was determined using intraclass correlation coefficients (ICCs) and Bland-Altman plots.Minimal bias was seen in all strain and strain rate measurements between field strengths. Using Tissue Tracking, strain and strain rate values derived from long-axis images showed poor to fair agreement (ICC range 0.39-0.71), whereas global longitudinal shortening and MAPSE showed good agreement (ICC = 0.81 and 0.80, respectively). Measures derived from short-axis images showed good to excellent agreement (ICC range 0.78-0.91). Similar results for the agreement of strain and strain rate measurements were observed with QStrain.The interfield strength agreement of short-axis derived LV strain and strain rate measurements at 1.5 T and 3 T was better than those derived from long-axis images; however, the agreement of global longitudinal shortening and MAPSE was good.2 TECHNICAL EFFICACY: Stage 2.

Late, repetitive or chronic remote ischaemic conditioning (CRIC) is a potential cardioprotective strategy against adverse remodelling following ST-segment elevation myocardial infarction (STEMI). In the randomised Daily Remote Ischaemic Conditioning Following Acute Myocardial Infarction (DREAM) trial, CRIC following primary percutaneous coronary intervention (P-PCI) did not improve global left ventricular (LV) systolic function. A post-hoc analysis was performed to determine whether CRIC improved regional strain. All 73 patients completing the original trial were studied (38 receiving 4 weeks’ daily CRIC, 35 controls receiving sham conditioning). Patients underwent cardiovascular magnetic resonance at baseline (5–7 days post-STEMI) and after 4 months, with assessment of LV systolic function, infarct size and strain (longitudinal/circumferential, in infarct-related and remote territories). At both timepoints, there were no significant between-group differences in global indices (LV ejection fraction, infarct size, longitudinal/circumferential strain). However, regional analysis revealed a significant improvement in longitudinal strain in the infarcted segments of the CRIC group (from − 16.2 ± 5.2 at baseline to − 18.7 ± 6.3 at follow up, p = 0.0006) but not in corresponding segments of the control group (from − 15.5 ± 4.0 to − 15.2 ± 4.7, p = 0.81; for change: − 2.5 ± 3.6 versus + 0.3 ± 5.6, respectively, p = 0.027). In remote territories, there was a lower increment in subendocardial circumferential strain in the CRIC group than in controls (− 1.2 ± 4.4 versus − 2.5 ± 4.0, p = 0.038). In summary, CRIC following P-PCI for STEMI is associated with improved longitudinal strain in infarct-related segments, and an attenuated increase in circumferential strain in remote segments. Further work is needed to establish whether these changes may translate into a reduced incidence of adverse remodelling and clinical events. Clinical Trial Registration: http://clinicaltrials.gov/show/NCT01664611.

Late, repetitive or chronic remote ischaemic conditioning (CRIC) is a potential cardioprotective strategy against adverse remodelling following ST-segment elevation myocardial infarction (STEMI). In the randomised Daily Remote Ischaemic Conditioning Following Acute Myocardial Infarction (DREAM) trial, CRIC following primary percutaneous coronary intervention (P-PCI) did not improve global left ventricular (LV) systolic function. A post-hoc analysis was performed to determine whether CRIC improved regional strain. All 73 patients completing the original trial were studied (38 receiving 4 weeks' daily CRIC, 35 controls receiving sham conditioning). Patients underwent cardiovascular magnetic resonance at baseline (5-7 days post-STEMI) and after 4 months, with assessment of LV systolic function, infarct size and strain (longitudinal/circumferential, in infarct-related and remote territories). At both timepoints, there were no significant between-group differences in global indices (LV ejection fraction, infarct size, longitudinal/circumferential strain). However, regional analysis revealed a significant improvement in longitudinal strain in the infarcted segments of the CRIC group (from - 16.2 ± 5.2 at baseline to - 18.7 ± 6.3 at follow up, p = 0.0006) but not in corresponding segments of the control group (from - 15.5 ± 4.0 to - 15.2 ± 4.7, p = 0.81; for change: - 2.5 ± 3.6 versus + 0.3 ± 5.6, respectively, p = 0.027). In remote territories, there was a lower increment in subendocardial circumferential strain in the CRIC group than in controls (- 1.2 ± 4.4 versus - 2.5 ± 4.0, p = 0.038). In summary, CRIC following P-PCI for STEMI is associated with improved longitudinal strain in infarct-related segments, and an attenuated increase in circumferential strain in remote segments. Further work is needed to establish whether these changes may translate into a reduced incidence of adverse remodelling and clinical events. Clinical Trial Registration: http://clinicaltrials.gov/show/NCT01664611 .

The pathophysiological and clinical significance of microvascular dysfunction (MVD) in patients with heart failure with preserved ejection fraction (HFpEF) remains uncertain.The aim of this study was to use cardiovascular magnetic resonance to: 1) quantify coronary microvascular function; 2) examine the relationship between perfusion and fibrosis; and 3) evaluate the impact of MVD and fibrosis on long-term clinical outcomes.In a prospective, observational study, patients with HFpEF and control subjects underwent multiparametric cardiovascular magnetic resonance (comprising assessment of left ventricular volumetry, perfusion, and fibrosis [focal by late gadolinium enhancement and diffuse by extracellular volume]). The primary endpoint was the composite of death or hospitalization with heart failure.One hundred and one patients with HFpEF (mean age 73 ± 9 years, mean ejection fraction 56% ± 5%) and 43 control subjects (mean age 73 ± 5 years, mean ejection fraction 58% ± 5%) were studied. Myocardial perfusion reserve (MPR) was lower in patients with HFpEF versus control subjects (1.74 ± 0.76 vs 2.22 ± 0.76; P = 0.001). MVD (defined as MPR 2.0) was present in 70% of patients with HFpEF (vs 48% of control subjects; P = 0.014). There was no significant linear correlation between MPR and diffuse fibrosis (r = -0.10; P = 0.473) and no difference in MPR between those with and without focal fibrosis (mean difference -0.03; 95% CI: -0.37 to 0.30). In the HFpEF group, during median follow-up of 3.1 years, there were 45 composite events. MPR was independently predictive of clinical outcome following adjustment for clinical, blood, and imaging parameters (1 SD increase: HR: 0.673 [95% CI: 0.463 to 0.978; P = 0.038]; HR: 0.694 [95% CI: 0.491 to 0.982; P = 0.039]; and HR: 0.690 [95% CI: 0.489 to 0.973; P = 0.034], respectively).MVD is highly prevalent among patients with HFpEF and is an independent predictor of prognosis. The lack of correlation between MVD and fibrosis may challenge the assertion of a direct causal link between these entities. (Developing Imaging and Plasma Biomarkers in Describing Heart Failure With Preserved Ejection Fraction [DIAMONDHFpEF]; NCT03050593).

Non-ST-elevation acute coronary syndrome (NSTE-ACS) comprises a broad spectrum of disease ranging from unstable angina to myocardial infarction. International guidelines recommend a routine invasive strategy for managing patients with NSTE-ACS at high to very high-risk, supported by evidence of improved composite ischaemic outcomes as compared with a selective invasive strategy. However, accurate diagnosis of NSTE-ACS in the acute setting is challenging due to the spectrum of non-coronary disease that can manifest with similar symptoms. Heterogeneous clinical presentations and limited uptake of risk prediction tools can confound physician decision-making regarding the use and timing of invasive coronary angiography (ICA). Large proportions of patients with suspected NSTE-ACS do not require revascularisation but may unnecessarily undergo ICA with its attendant risks and associated costs. Advances in coronary CT angiography and cardiac MRI have prompted evaluation of whether non-invasive strategies may improve patient selection, or whether tailored approaches are better suited to specific subgroups. Future directions include (1) better understanding of risk stratification as a guide to investigation and therapy in suspected NSTE-ACS, (2) randomised clinical trials of non-invasive imaging versus standard of care approaches prior to ICA and (3) defining the optimal timing of very early ICA in high-risk NSTE-ACS.

Background Cardiovascular magnetic resonance (CMR) has become the gold standard for the assessment of cardiac volumetry and function. Currently, multi-breath-hold, steady-state free precession (SSFP) short-axis stack is acquired. Hence, accelerated image acquisition may be desirable in order to improve the time efficiency of the examination and to reduce motion artefact in subjects experiencing difficulty breath-holding. Purpose To compare a non-breath-hold SSFP multi-slice real-time Cine sequence with the standard multi-breath-hold SSFP technique for the assessment of left ventricular (LV) volumes and systolic function. Methods Prospectively 20 patients referred for routine clinical CMR was assessed. Functional assessment was performed with a standard SSFP sequence (approximate acquisition matrix 256 × 166, acquisition voxel size 1.66 × 1.33 × 8 mm, 30 phases, TR 48.16, IPAT 3, either retrospectively or prospectively gated). Assessment was also carried out using a real time Cine sequence (approximate acquisition matrix 160 × 92, acquisition voxel size 3.26 × 2.5 × 8 mm, number of phases determined according to R-R interval, TR 42.84, IPAT 4). Quantification of end-diastolic volume index [EDVi], end-systolic volume index [ESVi] and ejection fraction [EF] was performed by a single observer, blinded. Image quality was graded using a 4-point scale. Results Scans from 20 patients (age 63.0±11.7 years, 13 male) were analysed. All images were analysable and image quality was rated as excellent/good in 85% of real-time images and 90% of standard cine images. The duration of imaging was 15±7 s for the real-time sequence and 383±139 s for the standard sequence (p Conclusion For assessment of LV volumes and function, non-breath-hold, real-time cine sequences are feasible in the clinical setting and achieves similar values to segmented breath-held cines. This technique may prove useful in patients with breath-holding difficulty, patients with arrhythmias, or to accelerate exam times to enhance patient flow.

Recent decades have witnessed a remarkable decline in the incidence and mortality of ST-segment–elevation myocardial infarction (STEMI).1 In Western countries, improvements in acute care have seen in-hospital mortality from STEMI decrease dramatically from ≈20% in the 1980s to ≈5% in the present day.1,2 However, declining mortality engenders an increasing number of survivors with residual cardiac damage and its associated sequelae. Infarct-related left ventricular (LV) remodeling predisposes to systolic dysfunction and the development of heart failure. Consequently, there is an increasing global incidence of ischemic heart failure, a condition whose mortality rate, in contrast to that of STEMI, has barely changed in the last 2 decades (53% survival at 5 years).3 Identifying those at risk of adverse remodeling and heart failure early may allow individualized, targeted treatment to ameliorate heart failure and thereby improve survival. See Article by Stiermaier et al Noninvasive imaging plays a key role in risk stratification post-STEMI. LV ejection fraction (EF) is an independent predictor of survival and forms the basis of treatment stratification (eg, device therapy, aldosterone antagonists).4 The prognostic impact of LV dilatation (as measured by end-diastolic and end-systolic volumes) in historical echocardiographic studies is also well established.5 A relatively recent addition to the diagnostic armamentarium is cardiovascular magnetic resonance (CMR). As well as providing a highly accurate and reproducible depiction of myocardial injury and function, CMR also affords additional prognostic markers. Infarct size (IS) as determined by gadolinium imaging is a stronger predictor of adverse remodeling than EF or volumetric indices and serves as a useful surrogate end point in clinical trials.6,7 Risk prediction is further enhanced by CMR assessment of microvascular obstruction (MVO). Arising …

In the clinical evaluation of coronary artery disease (CAD), a desirable goal is to identify functionally significant disease without recourse to physical or pharmacological stress. Previous studies using myocardial contrast echocardiography have demonstrated microvascular dilation at rest in post-stenotic myocardium (1). Blood oxygen level–dependent (BOLD) cardiac magnetic resonance is a technique that can detect myocardial ischemia (2). The transition from diamagnetic oxyhemoglobin to paramagnetic deoxyhemoglobin induces T2 or T2* differences, thereby generating oxygen-dependent magnetic resonance contrast. In diseased myocardium, BOLD signal differences relative to normal myocardium may reflect not only differences of blood oxygenation, but also of vascular volume. Increased microvascular volume, with concomitant increase in the absolute quantity of hemoglobin, is expected to alter BOLD signal. We postulated that BOLD imaging at rest could be exploited to detect functionally significant CAD without stress.

INTRODUCTION: Sudden and/or chronic exposure to catecholamines may predispose patients with phaeochromocytoma to cardiac pathology, including left ventricular (LV) hypertrophy, myocardial infarction, stress-induced cardiomyopathy and heart failure. This is a prospective, multicentre study using cardiovascular magnetic resonance (CMR) imaging to describe the variety and incidence of cardiac abnormalities in patients diagnosed with phaeochromocytoma. METHODS: Patients diagnosed with phaeochromocytoma (n = 50) were included. We prospectively recruited patients newly-diagnosed with confirmed phaeochromocytoma (n = 20, age 51 ± 14 yrs) who underwent CMR before and after curative surgical resection of the phaeochromocytoma (median follow-up 1 year). Previously-diagnosed patients who had curative surgery (n = 30, age 52 ± 14 yrs) were also recruited. Patients with known cardiac conditions were excluded. CMR included cine imaging for LV function, T2-weighted imaging for oedema and late gadolinium enhancement imaging to detect scarring. RESULTS: In newly-diagnosed patients, the mean LV ejection fraction was 67 ± 10% (range 47-88%; normal range 57-81%); Of these patients, 20% (n = 4/20) had mild global LV dysfunction (EF 47-56%). A significant proportion (65%, n = 13/20) demonstrated scarring, all with a non-ischaemic pattern (midwall/subepicardial/patchy), but the areas were small (

Objectives To evaluate the accuracy of adenosine myocardial contrast echocardiography (MCE) in diagnosing coronary artery disease (CAD). Background Adenosine stress echocardiography is not routinely used in the assessment of CAD. Since ultrasound microbubble contrast agents enable improved wall motion analysis and simultaneous assessment of myocardial perfusion, we sought to evaluate the diagnostic performance of combined wall motion/perfusion imaging with adenosine MCE in patients with suspected CAD. We evaluated the accuracy of adenosine MCE in identifying 1) the presence of anatomic disease, as defined by X-ray angiography, and 2) the functional significance of CAD, as determined by high field-strength (3-T), multiparametric cardiac magnetic resonance (CMR) imaging. Methods Sixty-five patients with suspected CAD were studied before angiography with MCE and CMR, at stress (140 μg/kg/min intravenous adenosine) and at rest. For MCE, 2-, 3- and 4-chamber long-axis images were acquired during intravenous sulfur hexafluoride infusion. For CMR, short-axis first-pass perfusion and delayed enhancement images were acquired following intravenous gadolinium–diethylenetriaminepentaacetic acid bolus injections (0.05 mmol/kg). Quantitative coronary angiography served as a reference standard for anatomic disease (significant CAD defined as ≥50% reference diameter in vessels with diameter ≥2 mm). Results Compared with X-ray angiography, MCE provided diagnostic accuracy of 82%, sensitivity of 85%, and specificity of 76% for detecting significant coronary stenosis. Disease location was also identified with reasonable accuracy (diagnostic accuracy 81% for left anterior descending disease, 77% for left circumflex artery disease, and 84% for right coronary artery disease). With CMR as the reference standard for functional assessment, MCE provided diagnostic accuracy of 79%, sensitivity of 85%, and specificity of 74%. Interobserver agreement for MCE was 79% (95% confidence interval: 67% to 88%). Conclusions Adenosine MCE achieved favorable diagnostic performance in identifying the presence and functional significance of coronary stenosis. Adenosine MCE may be useful in the clinical setting for evaluating patients with suspected CAD.

Background— Absolute quantification of perfusion with cardiovascular magnetic resonance has not previously been applied in patients with coronary artery bypass grafting (CABG). Owing to increased contrast bolus dispersion due to the greater distance of travel through a bypass graft, this approach may result in systematic underestimation of myocardial blood flow (MBF). As resting MBF remains normal in segments supplied by noncritical coronary stenosis ( Methods and Results— The study population comprised 28 patients undergoing elective CABG for treatment of multivessel coronary artery disease. Eligible patients had angiographic evidence of at least 1 myocardial segment subtended by a noncritically stenosed coronary artery (P =0.57). In the latter, MBF after revascularization did not change significantly from baseline (0.86±0.20 mL/min/g, P =0.82). Conclusions— Model-independent deconvolution analysis does not systematically underestimate blood flow in graft-subtended territories, justifying the use of this methodology to evaluate myocardial perfusion in patients with CABG.

To evaluate the accuracy of adenosine myocardial contrast echocardiography (MCE) in diagnosing coronary artery disease (CAD).Adenosine stress echocardiography is not routinely used in the assessment of CAD. Since ultrasound microbubble contrast agents enable improved wall motion analysis and simultaneous assessment of myocardial perfusion, we sought to evaluate the diagnostic performance of combined wall motion/perfusion imaging with adenosine MCE in patients with suspected CAD. We evaluated the accuracy of adenosine MCE in identifying 1) the presence of anatomic disease, as defined by X-ray angiography, and 2) the functional significance of CAD, as determined by high field-strength (3-T), multiparametric cardiac magnetic resonance (CMR) imaging.Sixty-five patients with suspected CAD were studied before angiography with MCE and CMR, at stress (140 μg/kg/min intravenous adenosine) and at rest. For MCE, 2-, 3- and 4-chamber long-axis images were acquired during intravenous sulfur hexafluoride infusion. For CMR, short-axis first-pass perfusion and delayed enhancement images were acquired following intravenous gadolinium-diethylenetriaminepentaacetic acid bolus injections (0.05 mmol/kg). Quantitative coronary angiography served as a reference standard for anatomic disease (significant CAD defined as ≥ 50% reference diameter in vessels with diameter ≥ 2 mm).Compared with X-ray angiography, MCE provided diagnostic accuracy of 82%, sensitivity of 85%, and specificity of 76% for detecting significant coronary stenosis. Disease location was also identified with reasonable accuracy (diagnostic accuracy 81% for left anterior descending disease, 77% for left circumflex artery disease, and 84% for right coronary artery disease). With CMR as the reference standard for functional assessment, MCE provided diagnostic accuracy of 79%, sensitivity of 85%, and specificity of 74%. Interobserver agreement for MCE was 79% (95% confidence interval: 67% to 88%).Adenosine MCE achieved favorable diagnostic performance in identifying the presence and functional significance of coronary stenosis. Adenosine MCE may be useful in the clinical setting for evaluating patients with suspected CAD.

Informed consent for emergency coronary artery bypass grafting (CABG) is routinely obtained from patients undergoing percutaneous coronary intervention (PCI) and diagnostic angiography. Given the recent technological and pharmacological advances as well as increasing operator experience, we sought to assess the contemporary incidence of emergency CABG following PCI in our centre. In a total of 7855 consecutive PCIs, the overall rate of emergency CABG was 0.11%, and the mortality risk was 0.67%. We believe that in the vast majority of patients undergoing PCI and diagnostic angiography, routine consent for emergency CABG is no longer appropriate.

© 2016 American College of Cardiology Foundation.Background Pheochromocytoma is associated with catecholamine-induced cardiac toxicity, but the extent and nature of cardiac involvement in clinical cohorts is not well-characterized. Objectives This study characterized the cardiac phenotype in patients with pheochromocytoma using cardiac magnetic resonance (CMR). Methods A total of 125 subjects were studied, including patients with newly diagnosed pheochromocytoma (n = 29), patients with previously surgically cured pheochromocytoma (n = 31), healthy control subjects (n = 51), and hypertensive control subjects (HTN) (n = 14), using CMR (1.5-T) cine, strain imaging by myocardial tagging, late gadolinium enhancement, and native T1 mapping (Shortened Modified Look-Locker Inversion recovery [ShMOLLI]). Results Patients who were newly diagnosed with pheochromocytoma, compared with healthy and HTN control subjects, had impaired left ventricular (LV) ejection fraction (990 ms, as compared with 1% in healthy and 2% in HTN subjects; p < 0.05), and focal fibrosis (59% had nonischemic late gadolinium enhancement, as compared with 14% in HTN subjects). Post-operatively, impaired LV ejection fraction typically normalized, but systolic and diastolic strain impairment persisted. Focal fibrosis (median 5% LV) and T1 abnormalities (median 12% LV) remained, the latter of which may suggest some diffuse fibrosis. Previously cured patients demonstrated abnormal diastolic strain rate (p < 0.001), myocardial T1 (median 12% LV), and small areas of focal fibrosis (median 1% LV). LV mass index was increased in HTN compared with healthy control subjects (p < 0.05), but not in the 2 pheochromocytoma groups. Conclusions This first systematic CMR study characterizing the cardiac phenotype in pheochromocytoma showed that cardiac involvement was frequent and, for some variables, persisted after curative surgery. These effects surpass those of hypertensive heart disease alone, supporting a direct role of catecholamine toxicity that may produce subtle but long-lasting myocardial alterations.