Influence of motion correction on the visual analysis of cardiac magnetic resonance stress perfusion imaging.

OBJECTIVE: Image post-processing corrects for cardiac and respiratory motion (MoCo) during cardiovascular magnetic resonance (CMR) stress perfusion. The study analyzed its influence on visual image evaluation. MATERIALS AND METHODS: Sixty-two patients with (suspected) coronary artery disease underwent a standard CMR stress perfusion exam during free-breathing. Image post-processing was performed without (non-MoCo) and with MoCo (image intensity normalization; motion extraction with iterative non-rigid registration; motion warping with the combined displacement field). Images were evaluated regarding the perfusion pattern (perfusion deficit, dark rim artifact, uncertain signal loss, and normal perfusion), the general image quality (non-diagnostic, imperfect, good, and excellent), and the reader's subjective confidence to assess the images (not confident, confident, very confident). RESULTS: Fifty-three (non-MoCo) and 52 (MoCo) myocardial segments were rated as 'perfusion deficit', 113 vs. 109 as 'dark rim artifacts', 9 vs. 7 as 'uncertain signal loss', and 817 vs. 824 as 'normal'. Agreement between non-MoCo and MoCo was high with no diagnostic difference per-patient. The image quality of MoCo was rated more often as 'good' or 'excellent' (92 vs. 63%), and the diagnostic confidence more often as "very confident" (71 vs. 45%) compared to non-MoCo. CONCLUSIONS: The comparison of perfusion images acquired during free-breathing and post-processed with and without motion correction demonstrated that both methods led to a consistent evaluation of the perfusion pattern, while the image quality and the reader's subjective confidence to assess the images were rated more favorably for MoCo.

Left Ventricular Hypertrabeculation Is Not Associated With Cardiovascular Morbity or Mortality: Insights From the Eurocmr Registry.

Aim: Left ventricular non-compaction (LVNC) is perceived as a rare high-risk cardiomyopathy characterized by excess left ventricular (LV) trabeculation. However, there is increasing evidence contesting the clinical significance of LV hyper-trabeculation and the existence of LVNC as a distinct cardiomyopathy. The aim of this study is to assess the association of LV trabeculation extent with cardiovascular morbidity and all-cause mortality in patients undergoing clinical cardiac magnetic resonance (CMR) scans across 57 European centers from the EuroCMR registry. Methods and Results: We studied 822 randomly selected cases from the EuroCMR registry. Image acquisition was according to international guidelines. We manually segmented images for LV chamber quantification and measurement of LV trabeculation (as per Petersen criteria). We report the association between LV trabeculation extent and important cardiovascular morbidities (stroke, atrial fibrillation, heart failure) and all-cause mortality prospectively recorded over 404 ± 82 days of follow-up. Maximal non-compaction to compaction ratio (NC/C) was mean (standard deviation) 1.81 ± 0.67, from these, 17% were above the threshold for hyper-trabeculation (NC/C > 2.3). LV trabeculation extent was not associated with increased risk of the defined outcomes (morbidities, mortality, LV CMR indices) in the whole cohort, or in sub-analyses of individuals without ischaemic heart disease, or those with NC/C > 2.3. Conclusion: Among 882 patients undergoing clinical CMR, excess LV trabeculation was not associated with a range of important cardiovascular morbidities or all-cause mortality over ~12 months of prospective follow-up. These findings suggest that LV hyper-trabeculation alone is not an indicator for worse cardiovascular prognosis.

Influence of contrast agent and spatial resolution on myocardial strain results using feature tracking MRI.

OBJECTIVES: Feature tracking for assessing myocardial strain from cardiac magnetic resonance (CMR) cine images detects myocardial deformation abnormalities with prognostic implication, e.g., in myocardial infarction and cardiomyopathy. Standards for image acquisition and processing are not yet available. Study aim was analyzing the influence of spatial resolution and contrast agent on myocardial strain results. METHODS: Seventy-five patients underwent CMR for analyzing peak systolic circumferential, longitudinal, and radial strain. Group A included n = 50 with normal left ventricular ejection fraction, no wall motion abnormality, and no fibrosis on late enhancement imaging. Group B included n = 25 with chronic myocardial infarct. For feature tracking, steady-state free precession cine images were acquired repeatedly. (1) Native standard cine (spatial resolution 1.4 × 1.4 × 8 mm3). (2) Native cine with lower spatial resolution (2.0 × 2.0 × 8 mm3). (3) Cine equal to variant 1 acquired after administration of gadoteracid. RESULTS: Lower spatial resolution was associated with elevated longitudinal strain (- 21.7% vs. - 19.8%; p < 0.001) in viable myocardium in group A, and with elevated longitudinal (- 17.0% vs. - 14.3%; p = 0.001), circumferential (- 18.6% vs. - 14.6%; p = 0.002), and radial strain (36.8% vs. 31.0%; p = 0.013) in infarcted myocardium in group B. Gadolinium administration was associated with reduced circumferential (- 21.4% vs. - 22.3%; p = 0.001) and radial strain (44.4% vs. 46.9%; p = 0.016) in group A, whereas strain results of the infarcted tissue in group B did not change after contrast agent administration. CONCLUSIONS: Variations in spatial resolution and the administration of contrast agent may influence myocardial strain results in viable and partly in infarcted myocardium. Standardized image acquisition seems important for CMR feature tracking. KEY POINTS: • Feature tracking is used for calculating myocardial strain from cardiac magnetic resonance (CMR) cine images. • This prospective study demonstrated that CMR strain results may be influenced by spatial resolution and by the administration of gadolinium-based contrast agent. • The results underline the need for standardized image acquisition for CMR strain analysis, with constant imaging parameters and without contrast agent.

Effect of Nitroglycerin on the Performance of MR Coronary Angiography.

PURPOSE: To systematically investigate the effect of sublingual glyceryl trinitrate (nitroglycerin=nitro=glyceryl trinitrate=GTN=C3 H5 N3 O9 [NTG]) on the diagnostic performance of MR coronary artery imaging (MRCA) to detect relevant coronary artery disease (CAD). MATERIALS AND METHODS: Thirty-five healthy volunteers and 25 patients with suspected or proven CAD (all in sinus rhythm) underwent MRCA before and after NTG using a contrast-agent free, three-dimensional, navigator-based, steady state free precession acquisition (voxel size 1.0 × 0.7 × 0.7 mm3 ) at 1.5 Tesla. Target parameters were stenosis detection (>50%), visible vessel length (straightened planar reconstruction) and vessel diameter (curved planar reconstruction, measured proximal/medial/distal). In patients, invasive coronary angiography served as reference. RESULTS: NTG led to increase of the coronary diameter both in healthy volunteers (right coronary artery [RCA]: 3.2 to 3.7 mm, P < 0.001; left anterior descending coronary artery [LAD]: 2.9 to 3.4 mm, P = 0.009; left circumflex coronary artery [LCx]: 2.8 to 3.3 mm, P < 0.001) and patients (RCA 3.5 to 4.0 mm, P = 0.01; LAD 3.3 to 3.7 mm, P = 0.008; LCx: 2.9 to 3.3 mm, P = 0.03). Visible vessel length increased after NTG for the LAD (volunteers: 72 to 84 mm, P = 0.03; patients: 56 to 78 mm, P = 0.01) and for LCx (volunteers: 48 to 60 mm, P = 0.02). Sensitivity to detect > 50% stenosis improved after NTG from 88.0 to 96%, specificity from 46.5 to 69.8%, diagnostic accuracy from 61.8 to 79.4% and positive/negative predictive value from 48.9 to 64.9% and 87.0 to 96.8%, respectively. CONCLUSION: Sublingual administration of NTG significantly enhanced the visibility of the coronary arteries and improved the detection of coronary artery stenosis. LEVEL OF EVIDENCE: 2 J. MAGN. RESON. IMAGING 2017;45:1419-1428.

Gender differences in therapeutic recommendation after diagnostic coronary angiography: insights from the Coronary Angiography and PCI Registry of the German Society of Cardiology.

BACKGROUND: There is information suggesting differences and underuse of invasive coronary diagnostic and therapeutic procedures in women compared to men. METHODS: Data from consecutive patients (pts) which were enrolled in the Coronary Angiography and PCI Registry of the German Society of Cardiology were analyzed. We compared gender-related differences in diagnosis and therapeutic recommendation of pts undergoing coronary angiography (XA) for stable coronary artery disease (CAD), non-ST elevation acute coronary syndromes (NSTE-ACS) and ST elevation myocardial infarction (STEMI). RESULTS: From 2004 until the end of 2009, data of 1,060,542 invasive procedures in 1,014,996 pts were prospectively registered. One-third (34.6%) of them were female. Women less often had significant CAD, irrespective of the indication for XA. In pts with relevant CAD, percutaneous coronary interventions (PCI) were recommended in 87.1% of women versus 89.1% of men with STEMI [age-adjusted OR (aOR) 0.98, 95% CI 0.93-1.04], in 67.1 vs. 66.8% in NSTE-ACS (aOR 1.10, 1.07-1.12), and in 50.3 vs 49.4% in stable CAD (aOR 1.07, 1.05-1.09). CONCLUSIONS: In pts with significant CAD, there was no difference in recommendation for PCI between the genders in stable CAD, whereas in STEMI and NSTE-ACS women were treated even more often with PCI. There were only minor differences in referral for CABG between women and men. Hence, our data provide strong evidence against a gender bias in use of invasive therapeutic procedures once the diagnosis of significant CAD has been confirmed.

Diagnostic performance of non-contrast-enhanced whole-heart magnetic resonance coronary angiography in combination with adenosine stress perfusion cardiac magnetic resonance imaging.

BACKGROUND: We sought to evaluate the diagnostic performance of 1.5-T non-contrast enhanced whole-heart magnetic resonance coronary angiography (MRCA) alone and in combination with adenosine stress cardiac magnetic resonance imaging (CMR-Perf). MRCA has been proposed to allow for detection of coronary artery disease (CAD). Yet, recent studies failed to show an incremental value of MRCA when added to CMR-Perf. METHODS: Non-Gadolinium 1.5-T contrast-enhanced, electrocardiogram-triggered, navigator-gated free-breathing MRCA was performed in 144 patients (pts) with suspected or known CAD. Accuracy of MRCA in detecting CAD was evaluated using X-ray coronary angiography as the reference. A novel algorithm was used to combine the results of MRCA and CMR-Perf. RESULTS: MRCA was diagnostic in 96/144 pts (67%) with regular breathing (mean age 62.5 ± 13); 77% of all coronary segments (939/1226) and 92% of segments suitable for percutaneous coronary intervention (792/866) were assessable. In 59 pts a novel algorithm to combine MRCA and CMR-Perf was performed with high diagnostic performance: accuracy, sensitivity, specificity, negative and positive predictive values were 91.5% (54/59; 95% CI, 84%-99%), 95.7% (22/23; 77-100), 88.9% (32/36; 74-96), 84.6% (22/26; 71-99), and 97.0% (32/33; 91-100). Compared to the combined use of CMR-Perf and late gadolinium enhancement, specificity with the novel algorithm significantly increased (P = .008). CONCLUSION: MRCA has a high assessability in segments suitable for percutaneous coronary intervention in pts with regular breathing. The combined use of MRCA and CMR-Perf improved specificity for the detection of significant CAD.

European Cardiovascular Magnetic Resonance (EuroCMR) registry--multi national results from 57 centers in 15 countries.

BACKGROUND: The EuroCMR registry sought to evaluate indications, image quality, safety and impact on patient management of clinical routine CMR in a multi-national European setting. Furthermore, interim analysis of the specific protocols should underscore the prognostic potential of CMR. METHODS: Multi-center registry with consecutive enrolment of patients in 57 centers in 15 countries. More than 27000 consecutive patients were enrolled. RESULTS: The most important indications were risk stratification in suspected CAD/Ischemia (34.2%), workup of myocarditis/cardiomyopathies (32.2%), as well as assessment of viability (14.6%). Image quality was diagnostic in more than 98% of cases. Severe complications occurred in 0.026%, always associated with stress testing. No patient died during or due to CMR. In 61.8% CMR findings impacted on patient management. Importantly, in nearly 8.7% the final diagnosis based on CMR was different to the diagnosis before CMR, leading to a complete change in management. Interim analysis of suspected CAD and risk stratification in HCM specific protocols revealed a low rate of adverse events for suspected CAD patients with normal stress CMR (1.0% per year), and for HCM patients without LGE (2.7% per year). CONCLUSION: The most important indications in Europe are risk stratification in suspected CAD/Ischemia, work-up of myocarditis and cardiomyopathies, as well as assessment of viability. CMR imaging is a safe procedure, has diagnostic image quality in more than 98% of cases, and its results have strong impact on patient management. Interim analyses of the specific protocols underscore the prognostic value of clinical routine CMR in CAD and HCM.

Acute adverse reactions to gadolinium-based contrast agents in CMR: multicenter experience with 17,767 patients from the EuroCMR Registry.

OBJECTIVES: The purpose of this study was to assess the frequency, manifestation, and severity of acute adverse reactions associated with administration of several gadolinium-based contrast agents to patients who underwent cardiac magnetic resonance (CMR) imaging in the EuroCMR (European Cardiovascular Magnetic Resonance) Registry multinational and multicenter setting. BACKGROUND: The frequency, manifestations, and severity of acute adverse reactions associated with gadolinium-based contrast agents in the specific setting of cardiovascular magnetic resonance have not been systematically evaluated yet. METHODS: This is a multicenter and multinational registry with consecutive enrollment of patients in 45 European centers. During the current observation, 17,767 doses of gadolinium-based contrast agent were administered to 17,767 patients. The mean dose was 25.6 ml (range 5 to 80 ml), which is equivalent to 0.128 mmol/kg (range 0.012 to 0.3 mmol/kg). RESULTS: Thirty acute adverse reactions due to contrast administration occurred (0.17%). All reactions were classified as mild according to the American College of Radiology definition. The most frequent complaints following contrast administration were rashes and hives (9 of 30), followed by nausea (7 of 30), and anxiety (6 of 30). The event rate ranged from 0.06% (linear nonionic agent gadodiamide) to 0.47% (linear ionic agent gadobenate dimeglumine). Interestingly, we also found different event rates between the three main indications for CMR imaging, ranging from 0.1% (risk stratification in suspected coronary artery disease) to 0.42% (viability in known coronary artery disease). CONCLUSIONS: The incidence of acute adverse reactions after administration of gadolinium-based contrast in the "off-label" setting of CMR in our population was not different from the incidence in the U.S. Food and Drug Administration-approved general radiology setting. Thus, the off-label use of gadolinium-based contrast in CMR should be regarded as safe concerning the frequency, manifestation, and severity of acute events.

Influence of small caliber coronary arteries on the diagnostic accuracy of adenosine stress cardiac magnetic resonance imaging.

BACKGROUND AND AIMS: Positive predictive value (PPV) of adenosine stress cardiac magnetic resonance (CMR) for coronary artery disease (CAD) is unsatisfactory. We investigated the impact of coronary caliber variability on this limitation in CMR performance. METHODS AND RESULTS: 206 consecutive patients with myocardial ischemia during CMR and subsequent coronary angiography (CA) were studied. Patients were examined in a 1.5-T scanner. After adenosine infusion, myocardial first-pass sequence using gadolinium-based contrast agent was performed and compared with rest perfusion. CAD was invasively confirmed in 165 [true positive (TP); PPV, 80.1%] and ruled out in 41 patients [false positive (FP)]. TP and FP were comparable for pre-test risk and CMR findings. We found a significant association between FP CMR and the presence of a small caliber coronary vessel (proximal diameter < one standard deviation below the mean) supplying the area of ischemia (chi-square 42.6, p < 0.0001). A small caliber artery ipsilateral to the ischemic region was a predictive parameter for FP versus TP discrimination (ROC area, 0.84 ± 0.04 vs. 0.59 ± 0.05; p < 0.0001). Further increment in diagnostic accuracy was achieved by including proximal ipsilateral/contralateral coronary diameter ratios (ROC area, 0.90 ± 0.03; p < 0.03). CONCLUSIONS: Small caliber coronary arteries found as normal variations in right-dominant or left-dominant circulation may account for hypoperfusion in the absence of coronary stenosis and thus may cause FP adenosine stress CMR results. Non-invasive assessment of proximal coronary diameters in the vessel supplying the area of ischemia could reduce FP rates, raise the diagnostic accuracy of CMR for CAD and minimize subsequent superfluous CA.

Combined assessment of myocardial perfusion and late gadolinium enhancement in patients after percutaneous coronary intervention or bypass grafts: a multicenter study of an integrated cardiovascular magnetic resonance protocol.

OBJECTIVES: We sought to assess the accuracy of an integrated cardiac magnetic resonance (CMR) protocol for the diagnosis of relevant coronary artery or bypass graft stenosis in patients with suspected coronary artery disease (CAD) or with previously performed percutaneous coronary intervention (PCI) or coronary bypass graft surgery (CABG). BACKGROUND: CMR is suitable for diagnosing inducible myocardial ischemia in patients with suspected CAD and has been proven to be a helpful diagnostic tool for decision of further treatment. However, little is known about its diagnostic accuracy in patients with known CAD who previously were treated by PCI or CABG. METHODS: A total of 477 patients with suspected CAD, 236 with previous PCI, and 110 after CABG referred for coronary X-ray angiography (CXA) underwent an integrated CMR examination before CXA. Myocardial ischemia was assessed using first-pass perfusion after vasodilator stress with adenosine (140 microg/kg/min for 3 min) using gadolinium-based contrast agents (0.1 mmol/kg). Late gadolinium enhancement (LGE) was assessed 10 min after a second contrast bolus. RESULTS: CXA demonstrated a relevant coronary vessel stenosis (> or =70% luminal reduction) in 313 (38%) patients using quantitative coronary analysis. The combination of CMR perfusion and LGE assessment for detecting a relevant coronary stenosis in patients with suspected CAD yielded sensitivity and specificity of 0.94 and 0.87, in PCI patients 0.91 and 0.90, and in CABG patients 0.79 and 0.77, respectively. CONCLUSIONS: A combined CMR protocol for the assessment of myocardial perfusion and LGE is feasible for the detection of relevant coronary vessel stenosis even in patients who previously were treated by PCI or CAG in a routine clinical setting. However, diagnostic accuracy is reduced in patients with CABG. This could be due to different flow and perfusion kinetic. Further studies are needed to optimize the clinical protocols especially in post-surgical patients.

Immunoglobulin G treatment of postcardiac surgery patients with score-identified severe systemic inflammatory response syndrome--the ESSICS study.

OBJECTIVE: A minority of patients develop severe systemic inflammatory response syndrome (SIRS) with high mortality following cardiopulmonary bypass-assisted cardiac surgery. We assessed whether intravenous immunoglobulin G (ivIgG) improves postoperative short-term (5-day) morbidity and reduces 28-day mortality in these patients. DESIGN: Randomized, double-blind, placebo-controlled, multicenter trial. SETTING: Intensive care units of 11 cardiothoracic centers. PATIENTS AND INTERVENTIONS: Of 6,984 patients screened, we identified 244 with severe SIRS (Acute Physiology and Chronic Health Evaluation II score > or = 28 on the first postoperative day). INTERVENTIONS: The 244 patients with severe SIRS were randomly assigned to receive an intravenous infusion of either albumin 0.1% (placebo group, 6 mL [6 mg]/kg of body weight on day 1 and 3 mL [3 mg]/kg of body weight on day 2) or immunoglobulin G 10% (ivIgG group, 6 mL [600 mg]/kg of body weight on day 1 and 3 mL [300 mg]/kg of body weight on day 2). MEASUREMENTS AND MAIN RESULTS: The prospectively defined primary end points were improvement in morbidity on day 5 and death from any cause assessed on day 28. A total of 218 patients received both doses of the study drug (placebo n = 108, ivIgG n = 110). Acute Physiology and Chronic Health Evaluation II scores in the placebo group decreased from 31.8 +/- 4.0 (day 1) to 25.8 +/- 9.3 (day 5) and in the ivIgG group from 31.8 +/- 3.4 (day 1) to 25.9 +/- 10.3 (day 5), with no significant difference between the groups (p = .56). The 28-day mortality rate was not significantly different between the groups (per protocol population, placebo group 31.5%, ivIgG group 39.1%; intent-to-treat population, placebo group 37.2%, ivIgG group: 44.7%). No effect of ivIgG on plasma levels of interleukin-6, tumor necrosis factor, and tumor necrosis factor receptor I/II was observed. Drug-related adverse events were rare in both groups. CONCLUSIONS: Patients undergoing cardiac surgery (involving cardiopulmonary bypass) who develop severe SIRS derive no improvement in short-term morbidity or 28-day mortality from ivIgG.

Score-based immunoglobulin G therapy of patients with sepsis: the SBITS study.

OBJECTIVE: Intravenous immunoglobulin as an adjunctive treatment in sepsis was regarded as promising by a Cochrane meta-analysis of smaller trials. In this phase III multicenter trial, we assessed whether intravenous immunoglobulin G (ivIgG) reduced 28-day mortality and improved morbidity in patients with score-defined severe sepsis. DESIGN: Randomized, double-blind, placebo-controlled, multicenter trial. SETTING: Twenty-three medical and surgical intensive care units in university centers and large teaching hospitals. PATIENTS: Patients (n = 653) with score-defined sepsis (sepsis score 12-27) and score-defined sepsis-induced severity of disease (Acute Physiology and Chronic Health Evaluation II score 20-35). INTERVENTIONS: Patients were assigned to receive either placebo or ivIgG (day 0, 0.6 g/kg body weight; day 1, 0.3 g/kg body weight). MEASUREMENTS AND MAIN RESULTS: The prospectively defined primary end point was death from any cause after 28 days. Prospectively defined secondary end points were 7-day all-cause mortality, short-term change in morbidity, and pulmonary function at day 4. Six hundred fifty-three patients from 23 active centers formed the intention-to-treat group, 624 patients the per-protocol group (placebo group, n = 303; ivIgG group, n = 321). The 28-day mortality rate was 37.3% in the placebo group and 39.3% in the ivIgG group and thus not significantly different (p = .6695). Seven-day mortality was not reduced, and 4-day pulmonary function was not improved. Drug-related adverse events were rare in both groups. Exploratory findings revealed a 3-day shortening of mechanical ventilation in the surviving patients and no effect of ivIgG on plasma levels of interleukin-6 and tumor necrosis factor receptors I and II. CONCLUSIONS: In patients with score-defined severe sepsis, ivIgG with a total dose of 0.9 g/kg body weight does not reduce mortality.

Plasma atrial natriuretic peptide and brain natriuretic peptide are increased in septic shock: impact of interleukin-6 and sepsis-associated left ventricular dysfunction.

OBJECTIVE: Interest has recently focused on the use of neurohormonal markers such as atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) as indices of left ventricular systolic dysfunction and prognosis in heart failure. Also, peptides belonging to the interleukin-6 (IL-6) family have been shown to induce ANP and BNP secretion. We hypothesized that BNP and ANP spillover in the peripheral circulation reflects left ventricular dysfunction and IL-6 production in septic shock. DESIGN AND SETTING: Retrospective, clinical study in the medical intensive care unit of a university hospital. PATIENTS AND PARTICIPANTS: 17 patients with septic shock and 19 control subjects. INTERVENTIONS: Collection of clinical and demographic data in relation to ANP, BNP, IL-6, and soluble TNF receptors (sTNF-R-p55, sTNF-R-p75) in plasma over a period of 4 days. MEASUREMENTS AND RESULTS: In septic shock we found a significant increase in ANP (82.7+/-9.9 vs. 14.9+/-1.2 pg/ml) and BNP (12.4+/-3.6 vs. 5.5+/-0.7 pg/ml). Plasma ANP peaked together with IL-6. Peaks of ANP and IL-6 were significantly correlated (r=0.73; p<0.01). BNP was inversely correlated to cardiac index (r=-0.56; p<0.05). CONCLUSIONS: ANP and BNP increase significantly in patients with septic shock. BNP reflects left ventricular dysfunction. ANP is related to IL-6 production rather than to cardiovascular dysfunction.