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Granulocyte colony-stimulating factor administration to CAD patients mobilizes cells with endothelial progenitor potential from bone marrow, but without objective evidence of cardiac benefit and with the potential for adverse outcomes in some patients.

In patients with chest pain who had MI excluded by troponin-I and non-diagnostic electrocardiograms, an adenosine CMR examination predicted with high sensitivity and specificity which patients had significant CAD during one-year follow-up. Furthermore, no patients with a normal adenosine CMR study had a subsequent diagnosis of CAD or an adverse outcome.

for the Limitation of Myocardial Injury following Thrombolysis in Acute Myocardial Infarction (LIMIT AMI) Study GroupBackground-The TIMI myocardial perfusion grade (TMPG) and ST-segment resolution both reflect perfusion and are associated with mortality after thrombolysis for acute myocardial infarction. We hypothesized that these measures would also be associated with infarct size by single photon emission computed tomography (SPECT). Methods and Results-In the LIMIT AMI trial (Limitation of Myocardial Injury following Thrombolysis in AcuteMyocardial Infarction) of lytic monotherapy versus lytic plus rhuMAb CD18, early 90-minute TMPG (nϭ221) and ST segment resolution (nϭ242) were compared with subsequent SPECT Technetium-99 m Sestamibi, measuring the percentage of the left ventricle with no Sestamibi uptake. Infarct sizes were larger with TMPG 0 or 1 (a closed or stained myocardium) than with TMPG 2 or 3 (open myocardium, median 13% versus 7%, Pϭ0.004). Infarcts were also larger in patients with no ST segment resolution (median 15%) or incomplete resolution (11%) than in those with complete resolution (6%, overall Pϭ0.0001). The difference in infarct size by TMPG persisted when stratified by category of ST resolution. Conclusions-There may be a pathophysiological link between early restoration of tissue-level perfusion and reduced subsequent infarct size that may partially explain why these early angiographic and electrocardiographic measures are associated with long-term survival. Key Words: myocardial infarction Ⅲ microcirculation Ⅲ electrocardiography Ⅲ angiography Ⅲ thrombolysis C urrent treatment of acute myocardial infarction (AMI) focuses on restoring epicardial blood flow. 1,2 Even when epicardial flow is restored, however, the 30-day mortality rate may be 7-fold higher in patients with abnormal microvascular flow compared with those with normal microvascular flow. 3 New therapies that may improve microvascular flow are being developed, as are techniques to measure it. 4 -7 These measurements, along with traditional estimates of infarct size, are associated with mortality after AMI. 3,8 -12 However, their relationships to each other are not well established, particularly the relationship between early angiographic and ECG measures and subsequent infarct size. We hypothesized that early abnormalities in perfusion would be associated with larger infarct size in the recent LIMIT AMI trial (Limitation of Myocardial Injury following Thrombolysis in Acute Myocardial Infarction). 13 MethodsThe LIMIT AMI trial of rhuMAb CD18, a leukocyte adhesion inhibitor, was a randomized, double-blind, placebo-controlled study that enrolled 394 subjects in 60 centers in the United States and Canada between September 1998 and March 2000. 13 Patients presenting within 12 hours of chest pain Ն30 minutes in duration and ST segment elevation on ECG were included. One of 2 doses of rhuMAb CD18 or placebo was administered before tissue plasminogen activator (tPA) or as soon as possible thereafter, along with aspirin and heparin. B...

Purpose: To develop and validate a three-dimensional (3D) single breath-hold, projection reconstruction (PR), balanced steady state free precession (SSFP) method for cardiac function evaluation against a two-dimensional (2D) multislice Fourier (Cartesian) transform (FT) SSFP method. Materials and Methods:The 3D PR SSFP sequence used projections in the x-y plane and partitions in z, providing 70 -80 msec temporal resolution and 1.7 ϫ 1.7 ϫ 8 -10 mm in a 24-heartbeat breath hold. A total of 10 volunteers were imaged with both methods, and the measurements of global cardiac function were compared. Results:Mean signal-to-noise ratios (SNRs) for the blood and myocardium were 114 and 42 (2D) and 59 and 21 (3D). Bland-Altman analysis comparing the 2D and 3D ejection fraction (EF), left ventricular end diastolic volume (LVEDV) and end systolic volume (LVESV), and end diastolic myocardial mass (LVEDM) provided values of bias Ϯ2 SD of 0.6% Ϯ 7.7 % for LVEF, 5.9 mL Ϯ 20 mL for LVEDV, -2.8 mL Ϯ 12 mL for LVESV, and -0.61 g Ϯ 13 g for LVEDM. 3D interobserver variability was greater than 2D for LVEDM and LVESV. Conclusion:In a single breath hold, the 3D PR method provides comparable information to the standard 2D FT method, which employs 10 -12 breath holds.

Dobutamine CMR is a highly reproducible technique with very good inter-observer variability and could be used as a specific endpoint in a relatively small clinical trial.

Pulmonary vein imaging is integral for planning atrial fibrillation ablation procedures. We tested the feasibility of quantifying pulmonary vein ostial diameter using two-dimensional cine cardiac magnetic resonance (2D cine CMR) and three-dimensional magnetic resonance angiography (3D MRA). Nine patients with a history of atrial fibrillation and 20 normal volunteers underwent 2D cine CMR and contrast-enhanced 3D MRA of pulmonary veins on a 1.5 T scanner. Pulmonary vein ostial diameters were measured and pulmonary vein vessel border sharpness was graded qualitatively. Both techniques provided excellent pulmonary vein imaging; however, 3D MRA was faster to perform. The average difference between the systolic and diastolic pulmonary vein diameter was 2.5 mm (23.2%, p < 0.0001) in normal volunteers and 2.2 mm (16.9%, p < 0.0001) in atrial fibrillation patients. The ostial diameter measurements by 3D MRA were significantly larger than on 2D cine CMR. Additionally, the pulmonary vein borders appeared sharper with 2D cine CMR compared to 3D MRA. In conclusion, the 2D images can resolve differences in diameter across the cardiac cycle, while the 3D images provide high quality anatomical depiction but blur borders due to pulsatile motion. We suggest a protocol combining 2D cine CMR and 3D MRA for comprehensive evaluation of pulmonary veins.

Left ventricular non-compaction (LVNC) is described as the persistence of trabeculated myocardium in the left ventricle (LV) and is optimally assessed by cardiac magnetic resonance (CMR). Right ventricular (RV) involvement in LVNC remains poorly studied. Consecutive patients (N = 14) diagnosed with LVNC by CMR were studied. Their clinical data were analyzed. In addition, CMR assessment included quantification of LV and RV volumes, mass, ejection fraction (EF), LV wall motion score, LV non-compacted segments and non-compacted to compacted myocardium ratios. Average age of presentation was 33.1 ± 17.6 years old, with 9 males (64%). Of these patients, 7 (50%) presented with acute heart failure and 3 (21%) with syncope, including 1 documented ventricular tachycardia. RV EF < 35% was identified in 7 (50%) of these patients. Patients with RV EF < 35% presented at a higher median New York Heart Association class (1 [IQR 1-2] vs. 3 [IQR 2-4], P = 0.021) and had significantly lower LV EF (50.7% ± 15.4 vs. 21.8% ± 19.9, P = 0.029), higher LV end diastolic (100.9 ml/m(2) ± 22.3 vs. 159.1 ml/m(2) ± 36.0, P = 0.002) and systolic volume indices (52.0 ml/m(2) ± 25.8 vs. 129.1 ml/m(2) ± 48.4, P = 0.002), higher LV wall motion score index (1.3 ± 0.5 vs. 2.2 ± 0.6, P = 0.004) and higher ratio of LV non-compacted to compacted myocardium (3.3 ± 0.6 vs. 4.1 ± 0.8, P = 0.026). All 4 patients that had ventricular tachycardia also had RV dysfunction. RV dysfunction was present in half of patients with LVNC. Significant RV dysfunction seems to be a marker of advanced LVNC and may carry a worse prognosis. Further studies in a larger sample of patients are needed to confirm those observations.