Evaluation of global left ventricular function assessment of non-fluorescent electromechanical endocardial mapping compared with biplane left ventricular contrast angiography.

Background. Little is known about the diagnostic accuracy of global LV function assessment by electromechanical endocardial mapping (EEM). The aim of the present study was to determine the relationship between global left ventricular (LV) function measured by EEM and biplane left ventricular contrast angiography (LVA) after ST-elevation myocardial infarction (STEMI).Methods. Thirty-seven patients underwent LVA and EEM during routine coronary angiography four months after primary percutaneous intervention for STEMI. Global LV function parameters were available from both techniques in all patients. LVA was regarded as reference standard.Results. All procedures were carried out without adverse events. Average age was 55+/-10 years and 84% were male. EEM showed an overestimation of end-diastolic volume (EDV) and end-systolic volume (ESV) of 6.5 ml and 25.5 ml, respectively. Correlation (r) was 0.84 (p<0.001) for EDV and 0.74 (p<0.001) for ESV. Average left ventricular ejection fraction (LVEF) measured by EEM was 17.2% point (+/-11.3% point) lower compared with LVA (r=0.69, p<0.001).Conclusion. Although global functional parameters by EEM correlated well with LVA, the relatively large differences in terms of absolute values for ventricular volumes and LVEF render the two techniques non-interchangeable for global LV-function-data. (Neth Heart J 2010;18:72-77.).

Matrix metalloproteinases 2 and 3 gene polymorphisms and the risk of target vessel revascularization after percutaneous coronary intervention: Is there still room for determining genetic variation of MMPs for assessment of an increased risk of restenosis?

OBJECTIVE: Mixed results have been reported of matrix metalloproteinases (MMP) and their association with restenosis after percutaneous coronary intervention (PCI). The current study examines whether multiple single nucleotide polymorphisms (SNPs), covering the full genomic region of MMP2 and MMP3, were associated with restenosis in the GENDER study population. METHODS AND RESULTS: The GENetic DEterminants of Restenosis (GENDER) study enrolled 3104 consecutive patients after successful PCI. The primary endpoint was clinical restenosis, defined as target vessel revascularization (TVR), occurring in 9.8% of the patients. From the Hapmap database, 19 polymorphisms of MMP2 and 11 of MMP3 were selected. Furthermore, in a subpopulation, a genome-wide association analysis (GWA) was performed. No significant association was found with any of the investigated SNPs, including the previously reported 5A/6A polymorphism (rs3025058), with regard to TVR using single SNP analysis or haplotype analysis. CONCLUSION: We found no significant association of MMP2 or MMP3 with TVR with this SNP-broad gene approach. Although we did not test all the known polymorphisms of these genes, using tagging analyses we examined those SNPs covering all known haplotypes of MMP2 and MMP3 to conclude that these genes do not correlate with a genetic risk of coronary restenosis after successful PCI.

Echocardiographic and electron beam tomographic assessment of stenosis in patients with aortic valve disease: gradient versus valve area.

BACKGROUND: Transthoracic echocardiography (TTE) is routinely used to evaluate aortic valve stenosis. However, it does not give reliable results in every patient. There is growing interest in electron-beam tomography (EBT) as a noninvasive cardiac imaging technique. The usefulness of EBT to evaluate aortic stenosis has yet to be evaluated. AIM: To compare EBT with TTE in assessing severity of aortic stenosis. METHODS: In total 47 patients (18 females, 29 males) underwent a contrast-enhanced EBT scan and TTE within 6±20 days. The calcium score of the aortic valve was determined and the aortic valve area (AVA) was measured by planimetry. A complete TTE study, during which the peak pressure gradient across the aortic valve was measured, was performed in all patients by an experienced sonographer. RESULTS: There was a significant correlation between AVA assessed by EBT and peak pressure gradient (r=-0.38, p=0.009). The calcium score of the aortic valve assessed by EBT correlated with peak pressure gradient (r=0.48, p=0.001). CONCLUSION: EBT is a useful noninvasive method to evaluate the severity of aortic stenosis. It holds the possibility of assessing the AVA as well as quantification of the degree of calcification.

Assessment of coronary artery bypass graft patency by multidetector computed tomography and electron-beam tomography.

This case report describes the use of retrospectively ECG-gated 16-slice multidetector computed tomography (MDCT) and electron-beam tomography (EBT) for assessing bypass graft patency in two patients with recurrent angina after coronary artery bypass graft surgery. The results of each tomographic modality were compared to the findings of traditional coronary angiography. In the first patient MDCT showed occlusion of the left internal mammary artery (LIMA) and saphenous vein graft after the second anastomosis. Coronary angiography confirmed these findings. In the second patient EBT showed patency of the LIMA and saphenous vein graft. After the first anastomosis of the saphenous vein graft, the connected vessel filled poorly. Coronary angiography confirmed both grafts to be patent, and detected an occlusion distal to the first anastomosis. These findings support the evidence that both MDCT and EBT are suitable techniques for establishing bypass graft patency by non-invasive means.

Myocardial viability assessment: poor correlation between electromechanical cardiac mapping and positron emission tomography in severe coronary artery disease.

BACKGROUND: An intracardial electromechanical mapping system has recently been introduced which offers the ability to perform on-line myocardial viability assessment in the catheterisation laboratory. Only a small number of studies have been performed to validate this potentially very useful technique. AIM: We sought to assess the correlation between viability assessment performed with both positron emission tomography (PET) and electromechanical cardiac mapping (EMM) in patients suffering from severe coronary artery disease, since PET is considered the golden standard in myocardial viability assessment. METHODS: Patients undergoing both EMM and PET analysis were systematically scanned for viability assessment. EMM analysis was performed for both linear local shortening and unipolar voltage. PET analysis consisted of dipyridamole stress and fluoro-deoxy-d-glucose (FDG) measurements. All data were converted to nine-segment bull's-eye maps to allow comparison. One single operator analysed all the data, blinded for clinical status. RESULTS: 34 patients suffering from severe coronary artery disease underwent both PET and EMM analysis. In total 253 EMM segments had more than four contact points and could be used for analysis. Unipolar voltage showed a trend towards lower values in infarcted segments; however, linear local shortening did not show any correlation. CONCLUSION: In this study viability assessment by EMM did not correspond with PET analysis. Although the advantage of having some form of online myocardial assessment is evident, operators should bare in mind that the quantitative EMM measurements are not an absolute substitute for nuclear imaging.

The assessment of autonomic function in patients with systemic amyloidosis: methodological considerations.

Autonomic neuropathy is a well-known and prognostically important feature of systemic amyloidosis. In other conditions, autonomic function is commonly assessed by cardiovascular reflex tests, described by Ewing, but the feasibility of these tests has not been investigated in patients with systemic amyloidosis. We studied autonomic function in amyloidotic patients using cardiovascular tests and assessed their feasibility. Patients with AA, AL and ATTR amyloidosis participated. In all patients, cardiovascular reflex testing (mental arithmetic stress test and head-up tilting, besides the Ewing-tests) was performed. Of the 46 patients included, only 28 patients could perform all 4 Ewing-tests. In particular, patients with AA amyloidosis secondary to rheumatoid arthritis could not perform standing up and the isometric handgrip test. However, when the mental stress test replaced the handgrip test and head-up tilting replaced standing up, in 45 of the 46 patients, autonomic function could be assessed with cardiovascular reflex tests. Half of the patients with AA amyloidosis had signs of autonomic neuropathy--which was more than expected. We propose to replace the isometric handgrip test with the mental arithmetic stress test and standing up with head-up tilting if a patient is not able to perform these tests.