Left ventricular filling patterns in patients with previous myocardial infarction measured by conventional cine cardiac magnetic resonance

To explore left ventricular filling patterns in patients with a history of previous myocardial infarction (MI) using time-volume curves obtained from conventional cine-cardiac magnetic resonance (CMR) examinations. Consecutive patients with a history of previous MI who were referred for CMR evaluation constituted the study population, and a consecutive cohort of sex and age-matched patients with a normal CMR constituted the control group. The following CMR diastolic parameters were evaluated: peak filling rate (PFR), time to PFR (tPFR), normalised PFR adjusted for diastolic volume at PFR (nPFR), and percent RR interval between end systole and PFR. Fifty patients were included, 25 with a history of previous MI and 25 control. The mean age was 59.6 ± 13.9 years and 27 (54%) were male. Within the control group, age was significantly related to PFR (r = -0.53, p = 0.007), whereas among patients with previous MI age was not related to PFR (r = -0.16, p = 0.44). PFR (252.4 ± 96.7 ml/s vs. 316.0 ± 126.4 ml/s, p = 0.05) and nPFR (1.6 ± 1.2 vs. 3.3 ± 1.5, p<0.001) were significantly lower in patients with previous MI, whereas no significant differences were detected regarding tPFR (143.0 ± 67.5 ms vs. 176.2 ± 83.9 ms, p = 0.13) and % RR to PFR (18.1 ± 9.7% vs. 20.6 ± 12.2%, p = 0.44). MI size was related to LV ejection fraction (r = -0.76, p<0.001), PFR (r = -0.40, p = 0.004), nPFR (r = -0.52, p<0.001) and left atrium area (r = 0.40, p = 0.004). Patients at the lowest PFR quartile (<200 ml/s) showed a larger MI size (Q1 26.5 ± 25.5%, Q2 15.5 ± 20.9%, Q3 6.3 ± 12.4%, Q4 8.8 ± 14.1%, p = 0.04). At multivariate analysis, MI size was the only independent predictor of the lowestPFR (p = 0.017). Infarct size has an impact on LV filling profiles, as assessed by conventional cine CMR without additional specific pulse sequences.Fil: Rodriguez Granillo, Gaston Alfredo. Sanatorio "Otamendi y Miroli S.A.". Servicio de Diagnóstico por Imágenes. Departamento de Imágenes en Cardiología. Centro de Investigaciones Cardiovasculares; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Mejía Campillo, Marlon. No especifíca;Fil: Rosales, Miguel A.. Sanatorio "Otamendi y Miroli S.A.". Servicio de Diagnóstico por Imágenes. Departamento de Imágenes en Cardiología. Centro de Investigaciones Cardiovasculares; ArgentinaFil: Bolzán, Gabriel. No especifíca;Fil: Ingino, Carlos. No especifíca;Fil: López, Federico. No especifíca;Fil: Degrossi, Elina. Sanatorio "Otamendi y Miroli S. A."; ArgentinaFil: Lylyk, Pedro. Sanatorio "Otamendi y Miroli S. A."; Argentin

Chronic myocardial infarction detection and characterization during coronary artery calcium scoring acquisitions

Background: Hypoenhanced regions on multidetector CT (MDCT) coronary angiography correlate with myocardial hyperperfusion. In addition to a limited capillary density, chronic myocardial infarction (MI) commonly contains a considerable amount of adipose tissue. Objective: We explored whether regional myocardial hypoenhancement on contrast-enhanced MDCT could be identified with standard coronary artery calcium (CAC) scoring acquisitions with noncontrast CT. Methods: Consecutive patients with a history of MI who were referred for contrast-enhanced MDCT from November 2006 until March 2009 were studied. Noncontrast CT for CAC scoring was also performed. The correlation between regional myocardial hypoenhancement on contrast-enhanced CT and regional myocardial hypoattenuated areas on noncontrast CT was defined. Results: Eighty-three patients (mean age, 61.5 ± 12.5 years; n = 67; 81% male) with previous MI were studied. A total of 1411 myocardial segments were evaluated. Two hundred thirty-nine segments (17%) showed myocardial hypoenhancement by MDCT and 140 segments (9.6%) by CAC. On a patient level, noncontrast CT showed a sensitivity, specificity, positive predictive value, (PPV) and negative predictive value (NPV) of 66% (95% CI, 0.53-0.77), 100% (95% CI, 0.76-1.00), 100% (95% CI, 0.90-1.00), and 41% (95% CI, 0.26-0.58), respectively, to detect myocardial hypoenhancement. On a per segment level, noncontrast CT showed a sensitivity, specificity, PPV, and NPV of 58% (95% CI, 0.51-0.64), 100% (95% CI, 0.99-1.00), 99% (95% CI, 0.94-1.00), and 92% (95% CI, 0.90-0.93), respectively, to detect myocardial hypoenhancement. Conclusions: Our findings suggest that chronic MI can be detected with standard CAC scoring acquisitions. © 2010 Society of Cardiovascular Computed Tomography.Fil: Rodriguez Granillo, Gaston Alfredo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Sanatorio "Otamendi y Miroli S. A."; ArgentinaFil: Rosales, Miguel A.. Sanatorio "Otamendi y Miroli S. A."; ArgentinaFil: Renes, Paola. Sanatorio "Otamendi y Miroli S. A."; ArgentinaFil: Diez, Eduardo. Sanatorio "Otamendi y Miroli S. A."; ArgentinaFil: Pereyra, Jorge. Sanatorio "Otamendi y Miroli S. A."; ArgentinaFil: Gomez, Estela. Sanatorio "Otamendi y Miroli S. A."; ArgentinaFil: De Lillo, Gustavo. Sanatorio "Otamendi y Miroli S. A."; ArgentinaFil: Degrossi, Elina. Sanatorio "Otamendi y Miroli S. A."; ArgentinaFil: Rodriguez, Alfredo E.. Sanatorio "Otamendi y Miroli S. A."; ArgentinaFil: McFadden, Eugene P.. Cork University Hospital; Irland

Signal density of left ventricular myocardial segments and impact of beam hardening artifact: Implications for myocardial perfusion assessment by multidetector CT coronary angiography

We sought to explore the normal myocardial signal density (SD) levels during multidetector computed tomography coronary angiography (MDCT-CA) acquisitions and evaluated the impact of beam hardening artifacts. Background: Since myocardial perfusion by MDCT is based on the myocardial signal density (SD), it is pivotal to determine the normal values of myocardial SD and to identify potential mechanisms of misinterpretation of perfusion defects. In routine MDCT acquisitions, we commonly visualize a considerable SD drop at the posterobasal wall resembling perfusion defects, being attributed to beam hardening artifacts. Consecutive asymptomatic patients without history of coronary artery disease (CAD) and low probability of CAD who were referred for MDCT evaluation at our institution due to inconclusive or discordant functional tests constituted the study population. Perfusion defects were defined as a myocardial segment having a SD two standard deviations below the average myocardial SD for the 16 left ventricular American Heart Association (AHA) segments. Thirty six asymptomatic patients constituted the study population. Myocardial SD was evaluated in 576 American Heart Association (AHA) segments and 36 posterobasal segments. The mean myocardial SD at the posterobasal segment was 53.5 ± 35.1 HU, whereas the mean myocardial SD at the basal, mid and apical myocardium was 97.4 ± 17.3, with significant differences (p < 0.001) between posterobasal and all AHA segments. Posterobasal "perfusion defects" were identified in 26 (72%) patients. The only variable associated to the presence of posterobasal SD deficit was the heart rate (61.8 ± 6.2 bpm vs. 56.3 ± 8.1 bpm, p = 0.04), whereas body mass index, blood SD of the left and right ventricles, contrast-to-noise ratio, and the extent of atherosclerosis were not related to the presence of "perfusion defects". In an asymptomatic population with no history of coronary artery disease, a myocardial signal density deficit mimicking a perfusion defect is a common finding in the posterobasal wall and is not related to body mass index or scan quality.Fil: Rodriguez Granillo, Gaston Alfredo. Sanatorio "Otamendi y Miroli S.A.". Servicio de Diagnóstico por Imágenes. Departamento de Imágenes en Cardiología. Centro de Investigaciones Cardiovasculares; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Rosales Arozarena, Miguel Esteban. Sanatorio "Otamendi y Miroli S.A.". Servicio de Diagnóstico por Imágenes. Departamento de Imágenes en Cardiología. Centro de Investigaciones Cardiovasculares; ArgentinaFil: Degrossi, Elina. Sanatorio "Otamendi y Miroli S.A.". Servicio de Diagnóstico por Imágenes. Departamento de Imágenes en Cardiología. Centro de Investigaciones Cardiovasculares; ArgentinaFil: Rodriguez, Alfredo E.. Sanatorio "Otamendi y Miroli S.A.". Servicio de Diagnóstico por Imágenes. Departamento de Imágenes en Cardiología. Centro de Investigaciones Cardiovasculares; Argentin