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Purpose: To investigate the incremental diagnostic value of dual-bolus over single-contrast-bolus first pass magnetic resonance myocardial perfusion imaging (MR-MPI) for detection of significant coronary artery disease (CAD)., Materials and Methods: Patients (n = 49) with suspected CAD underwent first pass adenosine stress and rest MR-MPI and invasive coronary angiography (CA). Gadolinium diethylenetriamine pentaacetic acid (Gd-DTPA) was injected with a prebolus (1 mL) and a large bolus (0.1 mmol/kg). For the single-bolus technique, the arterial input function (AIF) was obtained from the large-contrast bolus. For the dual-bolus technique, the AIF was reconstructed from the prebolus. Absolute myocardial perfusion was calculated by Fermi-model constrained deconvolution. Receiver operating characteristic (ROC) analysis was used to investigate diagnostic accuracy of MR myocardial perfusion imaging for detection of significant CAD on CA at vessel-based analysis., Results: The area under the curve (AUC) of the minimal stress perfusion value for the detection of significant CAD using the single-bolus and dual-bolus technique was 0.85 +/- 0.04 (95% confidence interval [CI], 0.77-0.93) and 0.77 +/- 0.05 (95% CI, 0.67-0.86), respectively., Conclusion: In this study the dual-bolus technique had no incremental diagnostic value over single-bolus technique for detection of significant CAD with the used contrast concentrations., ((c) 2010 Wiley-Liss, Inc.)

Background: Cardiovascular magnetic resonance imaging (CMR) with delayed contrast enhancement (DCE) using Gadolinium (Gd)-based magnetic contrastagents, is a technique which visualizes myocardial infarction (MI) as regions of bright signal (hyperenhancement) compared to normal myocardium. The prognostic value of DCE in patients with ischemic cardiomyopathy has not been fully characterized., Methods: All patients with a history of coronary artery disease (CAD) who underwent DCE-CMR imaging between September 1999 and July 2004 were included. CMR-variables were: left ventricular ejection fraction (LVEF), wall motion, mitral regurgitation (MR) and DCE scores. The patient's clinical status was assessed using the New York Heart Association-classification (NYHA)., Results: One hundred and ninety-three patients (age 63+/-11, 42 women), including 160 with prior MI, were studied. The mean LVEF was 40+/-14%. Most patients (88%) were in NYHA-class I or II, and 8% had moderate or severe MR. Thirteen patients died during follow-up. Patients who died had a lower baseline LVEF and more significant MR compared to survivors (P=0.04). A higher DCE score was associated with more significant MR (P=0.01). No significant association was demonstrated between NYHA-class and DCE (P=0.34) or between DCE score andmortality (P=0. 8)., Conclusion: The study reinforces the important prognostic value of resting LVEF and MR severity in patients with CAD and is the first to demonstrate an association between the degree of DCE and MR severity in these patients. Further investigations including a larger number of patients are needed to fully assess the prognostic value of DCE-CMR in ischemic cardiomyopathy.

Background: Quantification of late gadolinium enhanced cardiovascular magnetic resonance (LGE CMR) by objective window setting increases reproducibility and facilitates multicenter comparison and cooperation. So far, quantification methods or models have only been validated to postmortem animal studies. This study was undertaken to evaluate quantification of LGE in relation to the clinical standard of viability, i.e. functional outcome after revascularization.Thirty-eight patients with chronic ischemic myocardial dysfunction underwent cine and LGE 1 month before and cine CMR 6 months after coronary revascularization. Enhancement was quantified by thresholding window setting at: 2-8 SD above mean signal intensity of a remote normal region, and according to the full width at half maximum method (FWHM). Dysfunctional segments were divided in 5 groups according to segmental extent of enhancement (SEE): SEE 1--no enhancement to SEE 5--76-100% with each quantification method., Results: Quantification methods had a strong influence on SEE and total infarct size. Multilevel analysis showed that thresholding contrast images at 6 SD best predicted segmental functional outcome after revascularization, but the difference with other methods was small and non-significant., Conclusion: Simple thresholding techniques strongly influence global and segmental extent of LGE, but have relatively little influence on the accuracy to predict segmental functional improvement after revascularization.

Aims: We sought to evaluate the relation between long-term functional outcome after revascularization in patients with chronic ischaemic left ventricular (LV) dysfunction and baseline extent of myocardial fibrosis., Methods and Results: Thirty-five patients underwent cine and delayed contrast-enhanced cardiovascular magnetic resonance (deCMR) for the quantitative assessment of regional and global LV functions and segmental extent of hyperenhancement (SEH). Function was assessed 1 month before and 3, 6, and 24 +/- 12 months after revascularization, and temporal changes were related to baseline extent of hyperenhancement. The likelihood of functional improvement was inversely related to the SEH during the entire follow-up: at the end of the study period, segments with 1-25, 26-50, 51-75, and 76-100% SEH were 2, 5, 11, and 86 times, respectively, less likely to have functional improvement than segments without hyperenhancement (multilevel analysis, P < 0.001). Although improvement continued over the whole study period in all SEH groups, the time course was significantly more delayed in segments with more extensive hyperenhancement at baseline (multilevel analysis, P < 0.001)., Conclusion: In patients with chronic ischaemic LV dysfunction, improvement of dysfunctional but viable myocardium can be considerably delayed. Both the likelihood and the time course of long-term functional improvement are related to the baseline amount of scar, as visualized by deCMR.

Cardiovascular magnetic resonance imaging (CMR) with delayed contrast enhancement (DCE) using Gadolinium based contrast media is a recently developed technique which allows the direct visualisation of myocardial necrosis or fibrosis as regions of bright signal (hyperenhancement) compared with normal myocardium. The manuscript presents a review of the current clinical application of DCE-CMR for the diagnosis and prognosis of various common cardiac conditions such as ischaemic and non-ischaemic cardiomyopathies, and less common diseases such as cardiac sarcoidosis or Löffler endocarditis (Table 1).

Objective: The purpose of our study was to assess the presence and extent of delayed contrast enhancement of ventricular myocardium in pulmonary artery hypertension., Subjects and Methods: Fifteen patients (age, 45.6 +/- 13 years; 13 New York Heart Association class III) with pulmonary artery hypertension (11 idiopathic, four systemic sclerosis) were studied. All patients had undergone a comprehensive diagnostic workup, and pulmonary artery hypertension (mean pulmonary artery pressure, 54 +/- 16 mm Hg) was confirmed by cardiac catheterization. Cardiac MRI was performed on a 1.5-T scanner to determine ventricular volumes and mass. Delayed contrast enhancement of a mass was seen 10-20 minutes after the i.v. injection of 0.2 mmol/kg of gadopentetate dimeglumine using an inversion recovery gradient-echo sequence., Results: All patients showed delayed contrast enhancement at the insertion points of the right ventricular free wall to the interventricular septum (15 inferior, 13 anterior). The mean weight of the delayed contrast-enhanced myocardial mass was 3.1 +/- 1.9 g (size range, 0.3-3.9% of the total myocardial mass). The extent of the delayed contrast-enhancing myocardium was inversely related to the right ventricular ejection fraction (r = -0.63, p = 0.001), right ventricular stroke volume (r = -0.67, p = 0.006), and right ventricular end-systolic volume index (r = -0.51, p = 0.05) but not to any invasively measured hemodynamic index or N-terminal pro brain natriuretic peptide., Conclusion: Myocardial delayed contrast enhancement occurs frequently in patients with severe symptomatic pulmonary artery hypertension and is inversely related to measures of right ventricular systolic function.

In patients with chronic ischemic myocardial dysfunction, late gadolinium enhancement CMR (LGE-CMR) accurately depicts the regional extent of fibrosis and predicts functional recovery after revascularization. We hypothesized that the predictive accuracy of LGE-CMR could be optimized by not only taking into account the transmural extent of hyperenhancement but also the amount of residual, non-enhanced viable myocardium, and procedure related necrosis. We studied 45 patients with chronic ischemic left ventricular dysfunction, who underwent cine and LGE-CMR 1 month before and 3 months after surgical or percutaneous revascularization. Segmental and global function, scar, presence of a significant residual viable rim (defined as >or=4.5 mm), and procedure related necrosis were fully quantified using standardized methods and objective thresholds. Sixty percent of segments without hyperenhancement showed functional improvement at follow-up. No improvement was observed in segments with >75% segmental extent of hyperenhancement (SEH), while segments with 1-25%, 26-50%, and 51-75% SEH were 4, 8, and 20 times less likely to improve (multilevel analysis, p<0.001). Thickness of the viable rim largely paralleled total wall thickness; therefore, the presence of a significant viable rim did not provide additional diagnostic value beyond SEH. Procedure related necrosis was found in 12 (27%) patients. The presence of procedure related necrosis was the only (negative) predictor of changes in left ventricular volumes and ejection fraction. In conclusion, we found that functional outcome after revascularization was influenced by both transmural extent of hyperenhancement and procedure related necrosis. However, the presence of a significant residual, viable rim was of no additional diagnostic value.

Purpose: Cardiovascular magnetic resonance (CMR) is considered the standard imaging modality in clinical trials to monitor patients after acute myocardial infarction (AMI). However, limited data is available with respect to infarct size, presence, and extent of microvascular injury (MVO), and changes over time, in relation to cardiac function in these optimally treated patients. In this study, we prospectively investigate the change of infarct size over time, and the incidence and significance of MVO in a uniform, optimally treated patient group after AMI., Methods: Forty patients underwent cine and late gadolinium-enhanced CMR within 9 days and at 4 months after primary stenting. Left ventricular ejection fraction (LVEF), infarct size (IS) and MVO size were calculated., Results: IS decreased with 19.0% at follow-up (p<0.01). The 23 (57.5%) patients with MVO had larger infarct size, higher left ventricular volumes and lower LVEF and more involution of IS at follow-up. Overall, LVEF improved from 42.3+/-9.8% to 44.0+/-9.8% (p=0.06), irrespective of presence or size of MVO., Conclusion: Infarct size reduces over time by 19.0% in optimally treated patients after AMI. Despite optimal reperfusion, MVO was found in the majority of patients. Although patients with MVO had larger infarcts and worse indices of left ventricular remodelling, functional change at follow-up was comparable to patients without MVO.