Non-ischemic Pattern Research Articles

Nonischemic Myocardial Changes Detected by Cardiac Magnetic Resonance in Critical Care Patients with Sepsis

Nonischemic Myocardial Changes Detected by Cardiac Magnetic Resonance in Critical Care Patients with Sepsis

Cardiac involvement in hypereosinophilic syndromes detected by cardiac magnetic resonance imaging

Purpose: The hypereosinophilic syndromes (HES) are rare diseases characterized by blood hypereosinophilia and eosinophil-related organ damage, with the Churg-Strauss syndrome as the vasculitic subtype. Cardiac involvement, reported in 20-50% of patients in earlier series, carries poor prognosis and justifies aggressive immunosuppressive therapy. Cardiac magnetic resonance imaging (MRI) is the reference method for assessment of left ventricular (LV) function and allows evaluation of myocardial inflammation with consecutive oedema or myocardial fibrosis. We therefore sought to evaluate the frequency and patterns of cardiac manifestation of HES using cardiac MRI. Methods: 37 patients with definite HES were referred to our department for cardiac MRI because of possible cardiac involvement according to clinical, echocardiography and laboratory findings. MRI analysis included cine sequences for the assessment of LV function. T2-weighted imaging was conducted for assessment of myocardial oedema. Gadolinium late enhancement (LE) imaging was conducted for detection of fibrosis. Results: Of the 37 patients 14 were male. The mean age was 51.9±2.4 years. 20 patients also underwent coronary angiography, and only one patient had a significant stenosis of a marginal branch. Four patients (11%) had a cardiac MRI scan without pathological findings; three patients (8%) a non-circumferential PE of ≤ 5mm and an otherwise normal MRI. In 12 patients a PE ranging from 4 to 30mm was associated with other pathological findings. Quantitative analysis of LV function revealed a mean ejection fraction (EF) of 51.9±2.3%, EF was reduced (<55%) in 20 patients (54%). 7 patients (19%) showed hyperintense areas in T2-weighted images indicative of myocardial oedema. LE of the myocardium was observed in 23 patients (62%), all demonstrating a non-ischemic pattern of LE or multiple small endocardial LE zones not compatible with myocardial infarction due to coronary artery disease. Lastly, 4 patients (11%) showed the typical pattern of endomyocadial fibrosis with oedema and contrast enhancement of the myocardial/endocardial border zone and thrombotic material at the left and right ventricular apex. Conclusions: Cardiac MRI revealed pathologies in 90% of the study cohort. Yet, the pattern of cardiac manifestations varies significantly. More than half of the patients showed cardiomyopathy with reduced systolic LV function. Non-ischemic LE was present in the majority of patients and combined in one third of cases with myocardial oedema indicating acute inflammation. The unique pattern of endomyocardial fibrosis was observed in 11% of the patients.

Late Gadolinium Enhancement in Cardiac Transplant Patients Is Associated With Adverse Ventricular Functional Parameters and Clinical Outcomes

BackgroundHeart transplant recipients (HTRs) experience multiple cardiac complications, many of which might produce myocardial fibrosis. Cardiovascular magnetic resonance imaging (CMR) can image myocardial fibrosis using late gadolinium enhancement (LGE) imaging. We hypothesized that the presence and volume of LGE in heart transplant recipients correlates with left ventricular (LV) functional parameters and clinical outcomes. MethodsThirty-eight stable HTRs underwent a CMR study and clinical follow-up. ResultsIn 38 stable HTRs, LGE was seen in 19 patients (50%), of which 15 (79%) had a nonischemic pattern and 4 (21%) had an ischemic pattern. LGE volume was associated with reduced LV ejection fraction (EF) (R2 = 0.57; P = 0.001) and increased LV end-diastolic volume (R2 = 0.59; P = 0.001). The presence of LGE was associated with cardiovascular death or hospitalization within the next year (P = 0.04), and patients who died or were hospitalized had more LGE than those that were not hospitalized (15 g vs 7 g; P = 0.03). ConclusionsLGE is common in HTR and is associated with adverse ventricular remodelling and adverse clinical outcomes. LGE might be a useful noninvasive approach to monitor graft disease in asymptomatic patients after heart transplant.

Myocardial tissue characterisation with late gadolinium enhancement in rheumatoid arthritis, systemic lupus erythematosus and systemic sclerosis

Background Rheumatoid arthritis (RA), systemic lupus erythematosus (SLE) and systemic sclerosis (SSc) commonly involve the cardiovascular system, and are associated with high morbidity and mortality. Mechanisms of cardiovascular disease (CVD) involvement in these clinical entities are not fully understood. Furthermore, little is known about myocardial structure and function in these inflammatory arthropathies. Late gadolinium enhancement (LGE) cardiovascular magnetic resonance (CMR) imaging is a tool for noninvasive evaluation of myocardial fibrosis that has the advantage over other imaging techniques of being able to directly visualise both ischaemic and nonischaemic patterns of injury, and has prognostic significance. The purpose of this study was to assess the frequency and pattern of LGE in RA, SLE and SSc patients without any known CVD using CMR and to determine its relation to disease duration, vascular function (aortic distensibility; pulse wave velocity) and left ventricular

FREE-BREATHING 3D LATE GADOLINIUM ENHANCEMENT CARDIAC MR FOR THE EVALUATION OF LEFT VENTRICULAR INFARCTION IN A SWINE MYOCARDIAL INFARCTION MODEL

ObjectivesThe purpose of this study was to evaluate a new free-breathing 3D phase sensitive inversion-recovery (PSIR) turbo FLASH pulse sequence for the detection of left ventricular myocardial scar in a...

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091 T1-mapping has a high diagnostic performance in patients presenting with acute myocarditis: a cardiovascular magnetic resonance study

BackgroundThe diagnosis of acute myocarditis can be challenging. Cardiovascular magnetic resonance imaging (CMR) can be a useful tool in this setting but often requires multiple modalities for tissue characterisation, including...

Differentiation of Acute Myocarditis and Acute Myocardial Infarction by the Regional Distribution of Myocardial Irreversible Injury Using Cardiovascular Magnetic Resonance Imaging

In this study, we have sought for differences between cardiovascular magnetic resonance patterns of acute myocarditis and acute myocardial infarction. A prospective analysis of 110 consecutive patients was performed. The presence, precise location, and pattern of late gadolinium enhancement (LGE) by cardiovascular magnetic resonance were investigated. The subendocardial LGE pattern was much more frequent in the myocardial infarction group (76.7%) than myocarditis group (10.0%) (P<0.001). Meanwhile, midmyocardial LGE was much more typical of myocarditis (65.0%) than acute myocardial infarction (1.1%) (P<0.001), and epicardial LGE was also much more typical of myocarditis (55.0%) than acute myocardial infarction (0.0%) (P<0.001). Midmyocardial and epicardial LGE patterns were defined as a nonischemic LGE pattern more typical of myocarditis. Logistic regression analysis revealed that the subendocardial and midmyocardial LGE locations played the greatest role in differentiation between acute myocarditis and acute myocardial infarction. A statistical model based on midmyocardial LGE distribution and age showed a sensitivity of 90% and a specificity of 93.3% in differentiating between acute myocarditis and acute myocardial infarction. Our findings suggest that in clinical practice, differentiation between acute myocardial infarction and acute myocarditis can be done based on the subendocardial and midmyocardial LGE location. The presence of subendocardial LGE was found to be strongly associated with acute myocardial infarction; meanwhile, the presence of midmyocardial LGE indicated acute myocarditis. However, other clinical factors should also be taken into account when making the final diagnosis.

Mechanisms of Myocardial Infarction in Women Without Angiographically Obstructive Coronary Artery Disease

There is no angiographically demonstrable obstructive coronary artery disease (CAD) in a significant minority of patients with myocardial infarction, particularly women. We sought to determine the mechanism(s) of myocardial infarction in this setting using multiple imaging techniques. Women with myocardial infarction were enrolled prospectively, before angiography, if possible. Women with ≥50% angiographic stenosis or use of vasospastic agents were excluded. Intravascular ultrasound was performed during angiography; cardiac magnetic resonance imaging was performed within 1 week. Fifty women (age, 57±13 years) had median peak troponin of 1.60 ng/mL; 11 had ST-segment elevation. Median diameter stenosis of the worst lesion was 20% by angiography; 15 patients (30%) had normal angiograms. Plaque disruption was observed in 16 of 42 patients (38%) undergoing intravascular ultrasound. There were abnormal myocardial cardiac magnetic resonance imaging findings in 26 of 44 patients (59%) undergoing cardiac magnetic resonance imaging, late gadolinium enhancement (LGE) in 17 patients, and T2 signal hyperintensity indicating edema in 9 additional patients. The most common LGE pattern was ischemic (transmural/subendocardial). Nonischemic LGE patterns (midmyocardial/subepicardial) were also observed. Although LGE was infrequent with plaque disruption, T2 signal hyperintensity was common with plaque disruption. Plaque rupture and ulceration are common in women with myocardial infarction without angiographically demonstrable obstructive coronary artery disease. In addition, LGE is common in this cohort of women, with an ischemic pattern of injury most evident. Vasospasm and embolism are possible mechanisms of ischemic LGE without plaque disruption. Intravascular ultrasound and cardiac magnetic resonance imaging provide complementary mechanistic insights into female myocardial infarction patients without obstructive coronary artery disease and may be useful in identifying potential causes and therapies. Clinical Trial Registration- URL: http://www.clinicaltrials.gov. Unique identifier: NCT00798122.

Silent myocardial damage in cocaine addicts

BackgroundCocaine addiction is associated with either ischaemic or non-ischaemic cardiac complications. The prevalence of myocardial damage in asymptomatic addicts has never been evaluated by cardiovascular magnetic resonance (CMR), which allows...

The Other Side of Arrhythmogenic Right Ventricular Cardiomyopathy

Knowledge regarding arrhythmogenic right ventricular cardiomyopathy (ARVC) has increased dramatically since the publication of the original International Task Force diagnostic criteria in 1994. Based on symptomatic index cases and sudden cardiac death victims, the Task Force criteria emphasized manifestations observed only at the most severe end of the clinical spectrum of ARVC. It is now known that the phenotypic expression of the disease may vary considerably both in its severity and in the pattern of myocardial involvement. Recent familial studies have emphasized that, despite its name, the abnormalities of ARVC are not limited to the right ventricle. In recognition of the prevalence and clinical significance of left ventricular involvement in ARVC, a proposed modification to the original International Task Force criteria was recently published. We herein describe 3 cases of patients with ARVC who presented with left ventricular involvement as manifested by nonischemic pattern of delayed enhancement in the left ventricle.

Myocardial fibrosis is not associated with reduced quality of life in patients with dilated or hypertrophic cardiomyopathy

Background and objectives Patients with Dilated Cardiomyopathy (DCM) and Hypertrophic Cardiomyopathy (HCM) frequently demonstrate non-ischemic pattern myocardial fibrosis (MF) on delayed enhancement magnetic resonance imaging (DE-MRI). The clinical significance of this finding with respect to impact on Quality of Life (QOL) is poorly understood. In this study we identify the prevalence of MF in patients with HCM and DCM and assess its relationship with standardized measures of QOL. Methods One-hundred and seven consecutive patients with either DCM (n=50) or HCM (n=57) referred for MRI evaluation were identified. DCM was defined as a LVEF 3SD above reference myocardium) using validated commercial software. Results

Improving Nurses' Ability to Identify Anatomic Location and Leads on 12-Lead Electrocardiograms with ST Elevation Myocardial Infarction

ST segment elevation on the electrocardiogram (ECG) signifies complete occlusion of a coronary artery. Nurses play a significant role in obtaining, interpreting, and communicating 12-lead ECG findings. We evaluate a hand held paper tool to determine if it assists nurses; (1) identify the presence of ST elevation myocardial infarction (STEMI), (2) location, and (3) leads. A pre-test/post-test design was used. At pre-test, nurses from the emergency department (ED), coronary care unit (CCU), and the progressive care (PC) were given 6 patient scenarios (3 STEMI and 3 non-STEMI) and a corresponding 12-lead ECG. This was followed by a brief in-service on how to use the hand held tool. The nurse then interpret the same six ECGs (in a different order) using the hand held tool. Seventy-five nurses participated. Identification of STEMI location improved when the tool was used. Lead identification improved in 2 of the 3 STEMI scenarios. Overall, nurses' ability to correctly identify the 3 non-ischemic ECGs was low, and in one ECG was lower when the tool was used. For ECGs with a STEMI pattern an easy-to-learn tool improves nurses' ability to identify STEMI location. Nurses require education for identifying ECG leads, and non-ischemic ECG patterns.

Validation of segmental visual scar quantification in ischemic and non-ischemic cardiomyopathy: Comparison to signal threshold analysis of delayed enhancement MR images

Methods 161 consecutive patients with abnormal DE findings were included. Blinded visual quantification of segmental (AHA 17-segment model) scar was performed using a 5point scale, as follows; 0 = none, 1 = 1-25%, 2 = 26-50%, 3 = 51-75%, 4 = 76-100%. Each segment was assumed to represent 1/17th of the LV mass. Computerized, signal threshold-based analysis of total myocardial scar volume was also performed using cut-offs of 2, 3 and 5 SD above mean normal (nulled) myocardial signal. Comparison of visual scar quantification and signal-threshold based quantification was then performed using linear regression. Bland-Altman plots were then performed between visual scar volume and threshold-based scar volume measurements. Results Of 161 patients studied, the mean age was 57.5 ± 13.0 years. The mean LV ejection fraction was 46.3 ± 20.6%. Sixty-six (41%) patients had an ischemic DE pattern, 76 (47%) had a non-ischemic DE pattern, and 19 (12%) had a combined pattern. The Pearson correlation coefficients for visual versus threshold-based quantitative analysis at 5, 3, and 2 SD signal intensity thresholds were r = 0.81, r = 0.79 and r = 0.63 (p < 0.0001), respectively. Coefficients for patient sub-groups with ischemic and non-ischemic DE were r = 0.81, r = 0.81, r = 0.74 (p < 0.0001) and r = 0.72, r = 0.69, r = 0.46 (p = 0.0001), respectively. BlandAltman analysis of the mean difference in total scar volume between visual and threshold-based analysis (5 SD) for all patients, patients with ischemic DE, and patients with non-ischemic DE was 4.3 ± 7.9%, 4.8 ± 7.8, and 2.6 ± 7.6%, respectively.

Three-Dimensional Phase-Sensitive Inversion-Recovery Turbo FLASH Sequence for the Evaluation of Left Ventricular Myocardial Scar

The purpose of this study was to evaluate a new free-breathing 3D phase-sensitive inversion-recovery (PSIR) turbo FLASH pulse sequence for the detection of left ventricular myocardial scar. Patients with suspected myocardial scar were examined on a 1.5-T MR scanner for myocardial late enhancement after the administration of gadopentetate dimeglumine using a segmented 2D PSIR turbo FLASH sequence followed by a navigator-gated 3D PSIR turbo FLASH sequence. Image quality was scored by two independent readers using a 4-point Likert scale (0 = poor, nondiagnostic; 1 = fair, diagnostics may be impaired; 2 = good, some artifacts but not interfering in diagnostics; 3 = excellent, no artifacts). Scars were compared quantitatively in volume and graded qualitatively on the basis of size (area) and location. Thirty-three patients were scanned using both techniques. In 25 patients, the quality of the 3D PSIR images was acceptable. Scars were detected in 12 patients. Hyperenhanced scar volumes (p = 0.43), qualitative analysis of scar area (p = 0.78), and scar location (p = 0.68) were similar for both techniques. More small hyperenhanced scars, corresponding mostly to nonischemic distribution patterns, were detected using 3D PSIR than 2D PSIR. Although 2D and 3D results were found to be highly correlated for scar volume, Bland-Altman analysis indicated a systematic smaller infarct volume on the 2D PSIR scans (R(2) = 0.84). Free-breathing 3D PSIR turbo FLASH imaging is a promising technique for the assessment of left ventricular scar particularly for scar quantification and the detection of small nonischemic scars in the myocardium.

Prevalence, Pattern, and Functional Impact of Late Gadolinium Enhancement in Left Ventricular Hypertrophy due to Aortic Valve Stenosis

To assess the prevalence and pattern of myocardial late gadolinium enhancement (LGE) and its functional impact on patients with left ventricular hypertrophy caused by aortic valve stenosis. Cardiac magnetic resonance imaging of 40 patients (17 female, 23 male, mean age: 76.6 +/- 22.5 years) with known aortic valve stenosis (mean aortic valve area: 89.8 +/- 19.2 mm(2)) and without coronary artery disease was performed at 1.5 T using steady-state free precession sequences for aortic valve planimetry and for the assessment of left ventricular (LV) volumes and mass. Ten to 15 minutes after injection of 0.2 mmol Gd-DTPA per kilogram body weight, inversion-recovery prepared spoiled gradient echo images were acquired in standard long and short axis views to detect areas of LGE. LGE was observed in 32.5 % (13/40) of our patients. LGE was mainly located in the basal septal and inferior LV segments, and showed a non-ischemic pattern with sparing of the subendocardial region. Patients with LGE showed lower LV ejection fractions (55.5 +/- 13.8 % vs. 69.1 +/- 10.7 %, p = 0.0014), higher LV end-systolic volumes (59.8 +/- 33.3 ml vs. 36.6 +/- 16.0 ml, p = 0.0048), and LV masses (211.0 +/- 13.8 vs. 157.9 +/- 37.5 g, p = 0.0002) compared to patients without LGE. LGE is frequent in patients with hypertrophic left ventricles due to aortic valve stenosis and is associated with worse LV function.

Cardiac delayed enhancement distribution in extralysosomial glycogen storage disease

We describe magnetic resonance (MR) aspect of cardiac glycogenesis in a 49-years old man, presented a progressively declining cardiac function and negative coronary angiography. Delayed enhancement MR confirmed non-ischemic pattern with unusual diffuse distribution of Gadolinium. Cardiac biopsy revealed a Glycogen Storage Disease, extra-lysosomial type. Cardiac MR with analysis of delayed enhancement distribution is an emerging tool that can discriminate between ischemic and non-ischemic diseases; however to identify the precise aetiology of a non-ischemic distribution, myocardial biopsy is still needed.

An Ovine Model of Toxic, Nonischemic Cardiomyopathy—Assessment by Cardiac Magnetic Resonance Imaging

Background There is a paucity of published experience investigating novel treatment strategies in preclinical and clinical studies of nonischemic cardiomyopathy. We set out to validate an ovine model of doxorubicin-induced cardiomyopathy, using cardiac magnetic resonance (CMR) to assess cardiac function. Methods and Results Ten Merino sheep (51 ± 8 kg) underwent intracoronary infusions of doxorubicin (1 mg/kg dose) every 2 weeks. Cardiac magnetic resonance was performed at baseline and at 6 weeks after final doxorubicin dose, along with transthoracic echocardiography, measurement of right heart pressure, and cardiac output. After final CMR examination, heart specimens were harvested for histologic analysis. The total dose of doxorubicin administered per animal was 3.8 ± 0.5 mg/kg. Two animals died prematurely during the study protocol, with evidence of myocarditis. In the remaining 8 sheep, left ventricular ejection fraction dropped from 46.2 ± 4.7% to 31.3 ± 8.5% ( P < .001), accompanied by reductions in fractional shortening (31.6 ± 1.8% baseline versus 18.2 ± 3.9% final, P < .01), cardiac output (3.8 ± 0.6 L/min versus 3.0 ± 0.4 L/min, P < .05) and right ventricular ejection fraction (39.5 ± 5.6% versus 28.9 ± 9.6%, P < .05). However, significant end-diastolic dilatation of the left ventricle was not observed. Delayed gadolinium uptake was detected by CMR in 2 sheep, in a typical nonischemic pattern. Widespread, multifocal histologic abnormalities consisted of cardiomyocyte degeneration, vasculopathy, inflammatory infiltrates, and replacement fibrosis. Conclusions Moderate-severe cardiac dysfunction was reproducibly achieved through high-dose intracoronary doxorubicin, with acceptable animal mortality. CMR provides a powerful tool for assessing myocardial function, structural remodeling, and viability in such models.

Interpreting 12-Lead Electrocardiograms for Acute ST-Elevation Myocardial Infarction

In patients with acute myocardial infarction, early reperfusion and sustained patency of the culprit artery are important determinants of survival. The 12-lead electrocardiogram (ECG) is considered the noninvasive gold standard for identification of acute ST-elevation myocardial infarction. Nurses play a critical role in the process of obtaining, interpreting, and communicating ECG findings. This study evaluates nurses' ability to differentiate ischemic from nonischemic ECG patterns, to detect affected ECG leads and location of ischemia, and assesses skill level by hospital unit type. Seventy-five nurses were given a set of 6 patient scenarios, each with a corresponding 12-lead ECG, and asked to identify the presence or absence of ischemia. Fourteen (19%) of the 75 nurses correctly identified the presence or absence of ischemia in all 6 scenarios. Of the 3 ECGs with a myocardial infarction pattern, 59 (79%) of the nurses identified all 3 as ischemic; however, no one was able to determine the correct leads, location, or amplitude of ST-segment elevation. For the 3 nonischemic ECGs, 37 (49%) of the nurses identified a normal ECG as ischemic, 47 (63%) determined that an early repolarization pattern was ischemic, and 34 (45%) indicated that a left bundle branch block pattern was ischemic. These results not only identify educational opportunities but also provide important information for researchers implementing clinical trials evaluating the use of bedside ECG monitoring systems for detection of acute myocardial ischemia.

Delayed Hyperenhancement by Contrast-Enhanced Magnetic Resonance Imaging

The clinical applications of contrast-enhanced magnetic resonance (MR) imaging for defining viability are evolving as a result of the advantage of the technique's excellent spatial resolution. The value of delayed hyperenhancement imaging is for the accurate identification of the infarcted myocardium with resolution that allows determination of the transmural extent of myocardial injury. In addition, nonischemic patterns of myocardial injury such as dilated or hypertrophic cardiomyopathy have been reported in other disease states. Delayed hyperenhancement may have an additional role in guiding the management of or determining the prognosis for diseases such as myocarditis. In this study, the clinical application of delayed hyperenhancement is demonstrated for various cardiac diseases such as myocardial infarction, including right ventricular infarction; microvascular obstruction; and nonischemic cardiomyopathy such as dilated cardiomyopathy and myocarditis.