Cardiovascular Magnetic Resonance In Patients Research Articles

Cardiac Remodelling Identified by Cardiovascular Magnetic Resonance in Patients with Cirrhosis

Cardiac Remodelling Identified by Cardiovascular Magnetic Resonance in Patients with Cirrhosis

Cardiovascular Magnetic Resonance in patients with repaired Tetralogy of Fallot: the goal standard in preoperative assessment and follow up of injectable pulmonary valve implantation

Background Severe pulmonary regurgitation, progressive dilatation and dysfunction of the right ventricle are the most frequent reason of late morbidity post Fallot repair. Pulmonary valve replacement is often indicated in these patients. BioIntegral Injectable pulmonary valve (IPV) is an innovative less invasive technique, often done off cardiopulmonary bypass (CPB). Cardiovascular Magnetic Resonance (CMR) is fundamental tool to assess patient suitability for IPV insertion and in the clinical follow up.

Extracellular volume imaging by T1 mapping cardiovascular magnetic resonance in patients with clinically suspected myocarditis

Background Assessing the extracellular volume fraction (ECV) by T1 mapping is a promising cardiovascular magnetic resonance (CMR) approach to quantify myocardial injury. This study evaluated ECV imaging by T1 mapping CMR in patients with clinically suspected myocarditis. Methods T1 mapping was implemented into a standard CMR protocol in 113 patients with clinically suspected myocarditis at 1.5 Tesla. T1 quantification was performed for ECV -calculation using the modified Look-Locker inversionrecovery (MOLLI) sequence on three short-axes before and 15 minutes after administration of 0.075 mmol/kg gadolinium BOPTA, respectively. Global left ventricular ECV was calculated from T1 maps generated with a dedicated plug-in written for the OsiriX software: relaxation rates (1/T1 = R1) were calculated for myocardium and blood pool. The difference in R1 between pre- and post contrast media was calculated as ΔR1. Myocardial ECV was then estimated using the formula: ECV = 1-hematocrit * (ΔR1myocardium/ΔR1blood pool). Figure 1 demonstrates an example for T1 maps pre- and post contrast media in comparison with standard black-blood T2 STIR and late gadolinium enhancement (LGE) images. Results The final study population consisted of 96 patients after exclusion of 17 patients with concomitant coronary artery disease or severe left ventricular hypertrophy. Current clinical and CMR criteria identified 64 (67 %) patients with myocarditis and 32 (33 %) patients without myocarditis in the final study population. Global ECV was significantly larger in patients with myocarditis compared to patients without myocarditis (35±6 vs. 30±5 %, p<0.0001). Furthermore, global ECV was significantly larger in patients with focal scar compared to patients without focal scar on LGE CMR (35±5 vs. 33±7 %, p<0.05). ROC analysis revealed a sensitivity of 73 % and a specificity 67 % to identify patients with myocarditis using a global ECV ≧ 32 % cutoff (AUC = 0.76, p<0.0001). Conclusions Patients with myocarditis are characterized by an increased global ECV. Assessing global ECV by T1 mapping has great potential to improve the diagnostic and prognostic impact of CMR in patients with clinically suspected myocarditis.

Final infarct size measured by cardiovascular magnetic resonance in patients with ST elevation myocardial infarction predicts long-term clinical outcome: an observational study

Tailored heart failure treatment and risk assessment in patients following ST-segment elevation myocardial infarction (STEMI) is mainly based on the assessment of the left ventricular (LV) ejection fraction (EF). Assessment of the final infarct size in addition to the LVEF may improve the prognostic evaluation. To evaluate the prognostic importance of the final infarct size measured by cardiovascular magnetic resonance (CMR) in patients with STEMI. In an observational study the final infarct size was measured by late gadolinium enhancement CMR 3 months after initial admission in 309 patients with STEMI. The clinical endpoint was a composite of all-cause mortality and admission for heart failure. During the follow-up period of median 807 days (IQR: 669-1117) 35 events (5 non-cardiac deaths, 3 cardiac deaths, and 27 admissions for heart failure) were recorded. Patients with a final infarct size ≥ median had significantly higher event rates than patients with a final infarct size <median (17 vs. 6%; Log rank P = 0.002). In a multivariable Cox regression analysis, including age, peak troponin T, LVEF, LV volume index, and heart rate, the final infarct size remained significantly associated with the occurrence of subsequent events (adjusted hazard ratio 1.13 per 1% increase (95% CI: 1.05-1.21; P = 0.001). The overall Wald χ(2) value of a model including known risk factors was 47.3, which increased to 57.9 when the final infarct size was added (P = 0.001 for the difference). Assessment of the final infarct size by CMR 3 months after a STEMI provides strong independent prognostic information incremental to known risk factors including the LVEF, and may help to improve the risk stratification of STEMI patients.

Cardiovascular Magnetic Resonance Imaging in Hypertrophic Cardiomyopathy

The use of cardiovascular magnetic resonance in patients with hypertrophic cardiomyopathy over the last decade has helped elucidate the diagnosis, prognosis, pathophysiology, and management of this disease. Studies have shown that the use of magnetic resonance imaging in a patient with a permanent pacemaker and implantable cardioverter defibrillator is safe.

Circulation: Cardiovascular Imaging Editors' Picks

<i>Circulation: Cardiovascular Imaging</i> Editors' Picks

Quantitative assessment of right ventricular function in pectus excavatum

Pectus excavatum is a common congenital chest wall deformity. Underlying cardiac chambers, in particular the right atrium and right ventricle (RV), may be compressed between the vertebral column and the depressed sternum in patients with this thoracic deformity. Citing improvement in indices of cardiovascular function after corrective surgery, some investigators have suggested that the deformed chest may contribute to cardiopulmonary impairment. Although cardiopulmonary impairment certainly may contribute to symptoms in patients with pectus excavatum and guide the need for and timing of corrective surgery, guidelines for the assessment of resting cardiovascular function remain undefined. Furthermore, the qualitative echocardiographic assessment of RV function and volumes among patients with pectus excavatum may be technically difficult and limited by subjectivity. Quantitative echocardiographic parameters, such as tricuspid annular plane systolic excursion (TAPSE) and RV fractional area change, may offer a more accurate assessment of RV function in this anatomically distinct population. Cardiac magnetic resonance (CMR) imaging has emerged as the criterion standard in RV functional assessment and, more recently, has been validated in patients with pectus excavatum. We compared qualitative assessment of RV systolic impairment by visual echocardiographic inspection with quantitative assessment of RV function with CMR and echocardiographically derived TAPSE and RV fractional area change in a series of patients referred to our institution with mild to severe symptomatic pectus excavatum. Patients were being considered for corrective surgery. Our hypothesis was that the patients would be found to have normal RV function when assessed quantitatively, either through CMR or quantitative echocardiographic examination, despite impairment seen qualitatively.

Prognostic value of delayed enhancement cardiovascular magnetic resonance in patients with sarcoidosis

Methods Consecutive patients with biopsy proven extracardiac sarcoidosis or suspected isolated cardiac sarcoidosis were prospectively recruited. Patients with history of cardiac surgery, heart transplant, documented coronary artery disease, congenital heart disease were excluded. Of the 251 meeting criteria, 231 participants were enrolled (18 declined consent, 2 were minors) underwent CMR, and followed for 2.7±2.2 years for major adverse cardiac events (cardiac death, appropriate defibrillator shock, pacemaker placement, or heart transplantation). CMR images were analyzed by a consensus of two experienced readers who where blinded to all other data.

The Role of Cardiovascular Magnetic Resonance in Patients With Acute Coronary Syndromes

Cardiovascular magnetic resonance (CMR) imaging is a recognized technique for characterization of myocardial tissue in stable ischemic heart disease. In addition, CMR is emerging as a noninvasive imaging tool that can provide supporting information to guide treatment in acute coronary syndromes (ACSs). The advantages of using CMR acutely could potentially include triage/differential diagnosis in patients presenting with chest pain and troponin rise but without diagnostic electrocardiogram changes, assessment of severity of myocardial injury (irreversible vs reversible damage) in patients with ST-elevation myocardial infarction and non–ST-elevation myocardial infarction, and risk stratification and assessment of prognosis in patients with ACS. This review evaluates a potential clinical role of CMR in the acute setting, highlighting its advantages and limitations. This critical approach emphasizes areas of uncertainty and ongoing controversies but aims to equip the reader to evaluate the potential clinical application and the practicalities of CMR in patients presenting with ACS.

Prognostic value of dobutamine stress cardiovascular magnetic resonance in patients with previous coronary revascularization

The aim of this study was to assess the prognostic value of dobutamine stress cardiovascular magnetic resonance (DCMR) in patients with previous myocardial revascularization. The role of DCMR in the risk stratification of patients with previous coronary revascularization has not been well defined.

Prevalence of myocardial viability in dysfunctional areas by cardiovascular magnetic resonance in patients with coronary artery disease

Methods We analyzed 181 patients from the DEfibrillators To REduce Risk by MagnetIc ResoNance Imaging Evaluation Trial. All patients underwent cine and contrastenhanced (CE) CMR. Cine and CE studies were scored on a 17-segment model by the consensus of two readers. Cine images were scored for wall motion (WM): 0 = normal, 1 = mild hypokinesis, 2 = moderate to severe hypokinesis, 3 = akinesis, 4 = dyskinesis. CE images were scored for hyperenhanced (HE) infarct transmurality: 0 = none, 1 = 1-25% HE, 2 = 26-50% HE, 3 = 51-75% HE, 4 = 76-100% HE. Manually planimetered, quantitative analysis was also performed to obtain LV ejection fraction (EF) and infarct size using QMass MR 7.2 (Medis, Leiden, the Netherlands). DV-Myo segments were defined as having WM score ≥ 2 and HE score ≤ 1. DVMyo involving 2-4 of 17 segments (12-24% of LV) was considered prognostically significant only. DV-Myo involving ≥ 5 of 17 segments (≥ 29% of LV) was considered functionally significant. Results Baseline characteristics included male sex (84%) and mean age 61.5 ± 11.2 (31-88). Patients were on standard medical therapy, including beta-blockers (93%), ACE inhibitor/ARB (82%), anti-platelet (100%) and lipid lowering agents (94%). The population had a mean EF of 38.9 ± 11.6% (range 11.4 69.1%) and infarct size 17.3 ± 10.3% of LV (range 0 59.5%). A total of 3077 segments were evaluated, of which 442 (14%) segments met criteria for DV-Myo. Prognostically significant DV-Myo was present in 49/181 patients (27.1%). These patients had a mean of 2.7 ± 0.7 affected segments and a mean EF of 34.4 ± 7.7%. Functionally significant DV-Myo was present in an additional 33/181 patients (18.2%). These patients had a mean of 8.1 ± 3.0 affected segments and a mean EF of 26.2 ± 8.5%.

Cardiovascular magnetic resonance in patients with pectus excavatum compared with normal controls.

PurposeTo assess cardiothoracic structure and function in patients with pectus excavatum compared with control subjects using cardiovascular magnetic resonance imaging (CMR).MethodThirty patients with pectus excavatum deformity (23 men, 7 women, age range: 14-67 years) underwent CMR using 1.5-Tesla scanner (Siemens) and were compared to 25 healthy controls (18 men, 7 women, age range 18-50 years). The CMR protocol included cardiac cine images, pulmonary artery flow quantification, time resolved 3D contrast enhanced MR angiography (CEMRA) and high spatial resolution CEMRA. Chest wall indices including maximum transverse diameter, pectus index (PI), and chest-flatness were measured in all subjects. Left and right ventricular ejection fractions (LVEF, RVEF), ventricular long and short dimensions (LD, SD), mid-ventricle myocardial shortening, pulmonary-systemic circulation time, and pulmonary artery flow were quantified.ResultsIn patients with pectus excavatum, the pectus index was 9.3 ± 5.0 versus 2.8 ± 0.4 in controls (P < 0.001). No significant differences between pectus excavatum patients and controls were found in LV ejection fraction, LV myocardial shortening, pulmonary-systemic circulation time or pulmonary flow indices. In pectus excavatum, resting RV ejection fraction was reduced (53.9 ± 9.6 versus 60.5 ± 9.5; P = 0.013), RVSD was reduced (P < 0.05) both at end diastole and systole, RVLD was increased at end diastole (P < 0.05) reflecting geometric distortion of the RV due to sternal compression.ConclusionDepression of the sternum in pectus excavatum patients distorts RV geometry. Resting RVEF was reduced by 6% of the control value, suggesting that these geometrical changes may influence myocardial performance. Resting LV function, pulmonary circulation times and pulmonary vascular anatomy and perfusion indices were no different to controls.

Real-time cine and myocardial perfusion with treadmill exercise stress cardiovascular magnetic resonance in patients referred for stress SPECT.

BackgroundTo date, stress cardiovascular magnetic resonance (CMR) has relied on pharmacologic agents, and therefore lacked the physiologic information available only with exercise stress.Methods43 patients age 25 to 81 years underwent a treadmill stress test incorporating both Tc99m SPECT and CMR. After rest Tc99m SPECT imaging, patients underwent resting cine CMR. Patients then underwent in-room exercise stress using a partially modified treadmill. 12-lead ECG monitoring was performed throughout. At peak stress, Tc99m was injected and patients rapidly returned to their prior position in the magnet for post-exercise cine and perfusion imaging. The patient table was pulled out of the magnet for recovery monitoring. The patient was sent back into the magnet for recovery cine and resting perfusion followed by delayed post-gadolinium imaging. Post-CMR, patients went to the adjacent SPECT lab to complete stress nuclear imaging. Each modality's images were reviewed blinded to the other's results.ResultsPatients completed on average 9.3 ± 2.4 min of the Bruce protocol. Stress cine CMR was completed in 68 ± 14 sec following termination of exercise, and stress perfusion CMR was completed in 88 ± 8 sec. Agreement between SPECT and CMR was moderate (κ = 0.58). Accuracy in eight patients who underwent coronary angiography was 7/8 for CMR and 5/8 for SPECT (p = 0.625). Follow-up at 6 months indicated freedom from cardiovascular events in 29/29 CMR-negative and 33/34 SPECT-negative patients.ConclusionsExercise stress CMR including wall motion and perfusion is feasible in patients with suspected ischemic heart disease. Larger clinical trials are warranted based on the promising results of this pilot study to allow comparative effectiveness studies of this stress imaging system vs. other stress imaging modalities.

Prognostic value of dobutamine cardiovascular magnetic resonance in patients with peripheral arterial disease

Methods Clinical data and DCMR results were analyzed in patients with peripheral arterial disease undergoing DCMR between 2000 and 2004. Peripheral arterial disease was defined as significant stenosis or occlusion of peripheral arteries of the lower and upper extremity or of the carotid artery. After an average of 35 ± 17 months, 140 patients (median age, 65 years) were contacted and medical records were reviewed. Wall motion abnormalities (WMA) at rest and the presence of stress-induced WMA (ischemia) were assessed for each patient. Cardiac events, defined as cardiac death and non-fatal myocardial infarction, were assessed.

Diagnostic value of perfusion cardiovascular magnetic resonance in patients with angina pectoris but normal coronary angiograms assessed by intracoronary acetylcholine testing

BackgroundPerfusion cardiovascular magnetic resonance (CMR) has a high sensitivity for the detection of significant coronary artery disease (CAD). However, the specificity of this method is lower than its sensitivity. The...

P-18 Matrix Metalloproteinases and Late Gadolinium-Enhancement with Cardiovascular Magnetic Resonance in Patients with Dilated Cardiomyopathy

Enteroviruses have been implicated in the pathogenesis of idiopathic dilated cardiomyopathy (IDC). Recently, adenovirus and parvovirus have been proposed as etiological agents of IDC. Viral Infection in the myocardium of patients with end-stage IDC was evaluated. Myocardial specimens from 30 American IDC patients, obtained during heart transplants, and from 47 Japanese IDC patients, obtained during partial left ventriculectomy, were analyzed for the presence of viruses. Established RT-PCR or PCR was used to detect genomic sequences of enterovirus, influenza virus, mumps virus, adenovirus, herpes simplex virus, varicellazoster virus, and Epstein-Barr virus. Enteroviral RNA was detected in 7 (23%) of the 30 American patients and in 15 (32%) of the 47 Japanese patients. Sequence analysis revealed that the viruses detected were coxsackieviruses, such as coxsackievirus B3. No genomic sequences of other viruses were detected in the myocardium. A highly sensitive real-time LightCycler PCR assay was developed for the quantification of coxsackieviral genome in the myocardium. The linear dynamic range, spanning from 10 to 1010 copies, can detect viral genome in the myocardium of patients at all stages of the disease process. Low copy number of coxsackieviral RNA was detected in the myocardium of both American and Japanese patients. Conclusion: Low level of coxsackieviral RNA in the myocardium was demonstrated in a significant proportion of patients with end-stage IDC. There was no evidence of infection by other viruses in the myocardium of IDC patients.

Prognostic value of adenosine stress cardiovascular magnetic resonance in patients with low-risk chest pain.

BackgroundApproximately 5% of patients with an acute coronary syndrome are discharged from the emergency room with an erroneous diagnosis of non-cardiac chest pain. Highly accurate non-invasive stress imaging is valuable for assessment of low-risk chest pain patients to prevent these errors. Adenosine stress cardiovascular magnetic resonance (AS-CMR) is an imaging modality with increasing application. The goal of this study was to evaluate the negative prognostic value of AS-CMR among low-risk acute chest pain patients.MethodsWe studied 103 patients, mean 56.7 ± 12.3 years of age, with chest pain and no electrocardiographic evidence of ischemia and negative cardiac biomarkers of necrosis, who were admitted to the Cardiac Decision Unit of our institution. All patients underwent AS-CMR. A negative AS-CMR was defined as absence of all the following: regional wall motion abnormalities at rest; perfusion defects during stress (adenosine) and rest; and myocardial scar on late gadolinium enhancement images. The patients were followed for a mean of 277 (range 161-462) days. The primary end point was defined as the combination of cardiac death, nonfatal acute myocardial infarction, re-hospitalization for chest pain, obstructive coronary artery disease (>50% coronary stenosis on invasive angiography) and coronary revascularization.ResultsIn 14 patients (13.6%), AS-CMR was positive. The remaining 89 patients (86.4%), who had negative AS-CMR, were discharged. No patient with negative AS-CMR reached the primary end-point during follow-up. The negative predictive value of AS-CMR was 100%.ConclusionAS-CMR holds promise as a useful tool to rule out significant coronary artery disease in patients with low-risk chest pain. Patients with negative AS-CMR have an excellent short and mid-term prognosis.

Prognostic value of cardiovascular magnetic resonance in patients with strong suspicion for myocarditis

Prognostic value of cardiovascular magnetic resonance in patients with strong suspicion for myocarditis

2049 Improved detection of myocardial fibrosis using high-resolution, late gadolinium-enhanced cardiovascular magnetic resonance in patients with hypertrophic cardiomyopathy

Background Myocardial fibrosis as detected by late gadolinium enhanced cardiovascular MR (LGE-CMR) is common in patients with hypertrophic cardiomyopathy (HCM) although its clinical significance is uncertain. Current standard 2D LGE CMR imaging However, a recent postmortem report demonstrated an isolated foci of papillary muscle scarring which was not detected by conventional 2D LGE-CMR imaging. Three-dimensional high resolution (3D-HR) LGE CMR imaging has the potential for minimizing the partial volume (blood/papillary scar) effect of lower resolution/conventional 2D imaging and may improve our sensitivity for detecting myocardial fibrosis. Therefore, we sought to determine if 3D-HR LGECMR has a diagnostic advantage over conventional 2D LGE CMR for the detection of myocardial fibrosis in HCM patients.

2075 Papillary muscles and trabeculations significantly impact ventricular volume, ejection fraction, and regurgitation assessment by cardiovascular magnetic resonance in patients with hypertrophic cardiomyopathy

Introduction Measurement of valvular regurgitation is important in patients with hypertrophic cardiomyopathy (HCM). Using a cardiovascular magnetic resonance (CMR) manual partition method that includes papillary muscles and trabeculations as part of the ventricular cavity volume combined with phase velocity methods, the regurgitant fraction correlates well with assessment by Doppler echocardiography in patients with normal wall thickness. However, inclusion of papillary muscles and trabeculations as components of left ventricular (LV) mass may provide more accurate results. The impact of papillary muscle and trabeculation partitioning may be particularly prominent among patients with HCM for whom inclusion of these structures in the ventricular cavity volume may result in an overestimation of ventricular volumes and quantified valvular regurgitation.