Aernout M. Beek

Time course of functional recovery after revascularization of hibernating myocardium: a contrast-enhanced cardiovascular magnetic resonance study.

AIMSnWe 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.nnnMETHODS AND RESULTSnThirty-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).nnnCONCLUSIONnIn 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.

Early Electrocardiographic Findings and MR Imaging-Verified Microvascular Injury and Myocardial Infarct Size

OBJECTIVESnThis study investigated early electrocardiographic findings in relation to left ventricular (LV) function, extent and size of infarction, and microvascular injury in patients with acute myocardial infarction (MI) treated with percutaneous coronary intervention (PCI).nnnBACKGROUNDnThe electrocardiogram (ECG) is the most used and simplest clinical method to evaluate the risk for patients immediately after reperfusion therapy for acute MI. ST-segment resolution and residual ST-segment elevation have been used for prognosis in acute MI, whereas Q waves are related to outcome in chronic MI. We hypothesized that the combination of these electrocardiographic measures early after primary PCI would enhance risk stratification.nnnMETHODSnWe prospectively included 180 patients with a first acute ST-segment elevation MI to assess ST-segment resolution, residual ST-segment elevation, and number of Q waves using the 12-lead ECG acquired on admission and 1 h after successful PCI. The ECG findings were related to LV function, infarction size and transmurality, and microvascular injury as assessed with cine and gadolinium-enhanced cardiac magnetic resonance 4 +/- 2 days after reperfusion therapy.nnnRESULTSnResidual ST-segment elevation (beta = -2.00, p = 0.004) and the number of Q waves (beta = -1.66, p = 0.005) were independent ECG predictors of LV ejection fraction. Although the number of Q waves was the only independent predictor of infarct size (beta = 2.01, p < 0.001) and transmural extent of infarction (beta = 0.60, p < 0.001), residual ST-segment elevation was the only independent predictor of microvascular injury (odds ratio: 19.1, 95% confidence interval: 2.4 to 154, p = 0.005) in multivariable analyses. The ST-segment resolution was neither associated with LV function, infarct size, or transmurality indexes, nor with microvascular injury in multivariable analysis.nnnCONCLUSIONSnIn patients after successful coronary intervention for acute MI, residual ST-segment elevation and the number of Q waves on the post-procedural ECG offer valuable complementary information on prediction of myocardial function and necrosis and its microvascular status.

Diagnosis of myocarditis: Current state and future perspectives.

Myocarditis, i.e. inflammation of the myocardium, is one of the leading causes of sudden cardiac death (SCD) and dilated cardiomyopathy (DCM) in young adults, and is an important cause of symptoms such as chest pain, dyspnea and palpitations. The pathophysiological process of disease progression leading to DCM involves an ongoing inflammation as a result of a viral-induced auto-immune response or a persisting viral infection. It is therefore crucial to detect the disease early in its course and prevent persisting inflammation that may lead to DCM and end-stage heart failure. Because of the highly variable clinical presentation, ranging from mild symptoms to severe heart failure, and the limited available diagnostic tools, the evaluation of patients with suspected myocarditis represents an important clinical dilemma in cardiology. New approaches for the diagnosis of myocarditis are needed in order to improve recognition, to help unravel its pathophysiology, and to develop new therapeutic strategies to treat the disease. In this review, we give a comprehensive overview of the current diagnostic strategies for patients with suspected myocarditis, and demonstrate several new techniques that may help to improve the diagnostic work-up.

Cell Therapy in Reperfused Acute Myocardial Infarction Does Not Improve the Recovery of Perfusion in the Infarcted Myocardium: A Cardiac MR Imaging Study

PURPOSEnTo investigate the effects of cell therapy on myocardial perfusion recovery after treatment of acute myocardial infarction (MI) with primary percutaneous coronary intervention (PCI).nnnMATERIALS AND METHODSnIn this HEBE trial substudy, which was approved by the institutional review board (trial registry number ISRCTN95796863), the authors assessed the effects of intracoronary infusion with bone marrow-derived mononuclear cells (BMMCs) or peripheral blood-derived mononuclear cells (PBMCs) on myocardial perfusion recovery by using cardiac magnetic resonance (MR) imaging after revascularization. In 152 patients with acute MI treated with PCI, cardiac MR imaging was performed after obtaining informed consent-before randomization to BMMC, PBMC, or standard therapy (control group)-and repeated at 4-month follow-up. Cardiac MR imaging consisted of cine, rest first-pass perfusion, and late gadolinium enhancement imaging. Perfusion was evaluated semiquantitatively with signal intensity-time curves by calculating the relative upslope (percentage signal intensity change). The relative upslope was calculated for the MI core, adjacent border zone, and remote myocardium. Perfusion differences among treatment groups or between baseline and follow-up were assessed with the Wilcoxon signed rank or Mann-Whitney U test.nnnRESULTSnAt baseline, myocardial perfusion differed between the MI core (median, 6.0%; interquartile range [IQR], 4.1%-8.0%), border zone (median, 8.4%; IQR, 6.4%-10.2%), and remote myocardium (median, 12.2%; IQR, 10.5%-15.9%) (P < .001 for all), with equal distribution among treatment groups. These interregional differences persisted at follow-up (P < .001 for all). No difference in perfusion recovery was found between the three treatment groups for any region.nnnCONCLUSIONnAfter revascularization of ST-elevation MI, cell therapy does not augment the recovery of resting perfusion in either the MI core or border zone.

Feasibility of Cardiovascular Magnetic Resonance of Angiographically Diagnosed Congenital Solitary Coronary Artery Fistulas in Adults

OBJECTIVEnTo evaluate the use of cardiovascular magnetic resonance (CMR) to visualize angiographically-detected congenital coronary artery fistulas in adults.nnnMETHODSnCMR techniques were used to study 13 patients, recruited from the Dutch Registry, with previously angiographically diagnosed fistulas.nnnRESULTSnCoronary fistulas were detected in 10 of 13 (77%) patients by CMR and, retrospectively, in two (92%) more. In 93% of these, it was possible to determine the origin and the outflow site of the fistulas. Cardiovascular magnetic resonance allowed demonstration of dilatation of the fistula-related coronary artery in all cases. Tortuosity of fistulas was detected in all visualized patients. Uni-or bilaterality of fistulas as seen on CAG was proven on CMR in all patients. Flow measurement could be performed in 8 patients. A fairly good correlation (r = 0.72) was found between angiographic (mean 6.2 mm, range 1-16) and cardiovascular magnetic resonance (mean 6.3 mm, range 3-15) measured fistulous diameters.nnnCONCLUSIONSnCardiovascular magnetic resonance of congenital fistulas with clinical significant shunting is feasible and can provide additional physiological data complementary to the findings of conventional coronary angiography.

The influence of microvascular injury on native T1 and T2* relaxation values after acute myocardial infarction: implications for non-contrast-enhanced infarct assessment

ObjectivesNative T1 mapping and late gadolinium enhancement (LGE) imaging offer detailed characterisation of the myocardium after acute myocardial infarction (AMI). We evaluated the effects of microvascular injury (MVI) and intramyocardial haemorrhage on local T1 and T2* values in patients with a reperfused AMI.MethodsForty-three patients after reperfused AMI underwent cardiovascular magnetic resonance imaging (CMR) at 4 [3-5] days, including native MOLLI T1 and T2* mapping, STIR, cine imaging and LGE. T1 and T2* values were determined in LGE-defined regions of interest: the MI core incorporating MVI when present, the core-adjacent MI border zone (without any areas of MVI), and remote myocardium.ResultsAverage T1 in the MI core was higher than in the MI border zone and remote myocardium. However, in the 20 (47%) patients with MVI, MI core T1 was lower than in patients without MVI (MVI 1048±78ms, no MVI 1111±89ms, p=0.02). MI core T2* was significantly lower in patients with MVI than in those without (MVI 20 [18-23]ms, no MVI 31 [26-39]ms, p<0.001).ConclusionThe presence of MVI profoundly affects MOLLI-measured native T1 values. T2* mapping suggested that this may be the result of intramyocardial haemorrhage. These findings have important implications for the interpretation of native T1 values shortly after AMI.Key points• Microvascular injury after acute myocardial infarction affects local T1 and T2* values.• Infarct zone T1 values are lower if microvascular injury is present.• T2* mapping suggests that low infarct T1 values are likely haemorrhage.• T1 and T2* values are complimentary for correctly assessing post-infarct myocardium.

Double orifice mitral valve visualized on echocardiography and MRI

A 21-year-old, previously healthy, female presented with complaints of palpitations. The physical examination, ECG and a 24-hour Holter investigation were unremarkable. n nA transthoracic echocardiogram demonstrated a double orifice mitral valve (DOMV) (Fig.xa01). Cardiac magnetic resonance imaging was performed in order to exclude other congenital heart problems (Fig.xa02). There was no evidence of mitral valve stenosis, regurgitation or other cardiac morphological abnormalities. n n n nFig.xa01 n nTransthoracic echocardiogram. a Apical 4-chamber view with ‘seagull’ appearance of the mitral valve (white arrow); b Parasternal short axis with bridge of tissue (dark arrow) dividing the mitral valve into two equal orifices n n n n n nFig.xa02 n nCardiac MRI. a Short-axis mitral valve gradient echo cine MRI image demonstrating the two orifices b) Corresponding phase contrast velocity encoded MRI (maximum velocity 100xa0cm/s) image demonstrating normal flow through the mitral valve n n n nFirst described in 1876 by Greenfield [1], DOMV is an uncommon anomaly which, as its name indicates, has a single mitral annulus and opens into the left ventricle through two orifices. Depending on the relative size and location of the two orifices, DOMV can be classified into an eccentric type (found in 85% of cases) and a central or bridge type (as in our patient’s case) [2]. Mitral stenosis or regurgitation and other congenital malformations such as atrioventricular or ventricular septal defects may be associated with DOMV [3, 4].