Estefania De Garate

Myocardial Infarction With Nonobstructed Coronary Arteries: Impact of CMR Early After Presentation

Seven to 15% of patients with acute coronary syndrome (ACS) have nonobstructed coronary arteries, an entity that is known as myocardial infarction with nonobstructed coronary arteries (MINOCA) [(1)][1]. In these patients, cardiac magnetic resonance (CMR) can identify different underlying etiologies

Native T1 mapping to detect extent of acute and chronic myocardial infarction: comparison with late gadolinium enhancement technique

Investigate whether native-T1 mapping can assess the transmural extent of myocardial infarction (TEI) thereby differentiating viable from non-viable myocardium without the use of gadolinium-contrast in both acute and chronic myocardial infarction (aMI and cMI). Sixty patients (30 cMI > 1 year and 30 aMI day 2 STEMI) and 20 healthy-controls underwent 1.5 T CMR to assess left ventricular function (cine), native-T1 mapping (MOLLI sequence 5(3)3, motion-corrected) and the presence and TEI from late gadolinium enhancement (LGE) images. Segments with TEI > 75% was considered non-viable. Gold-standard LGE-TEI was compared with corresponding segmental native-T1. Segmental native-T1 correlated significantly with TEI (R = 0.74, p < 0.001 in cMI and R = 0.57, p < 0.001 in aMI). Native-T1 differentiated segments with no LGE (1031 ± 31 ms), LGE positive but viable (1103 ± 57 ms) and LGE positive but non-viable (1206 ± 118 ms) in cMI (p < 0.01). It also differentiated segments with no LGE (1054 ± 65 m), LGE positive but viable (1135 ± 73 ms) and LGE positive but non-viable (1168 ± 71 ms) in aMI (p < 0.01). ROC analysis demonstrated excellent accuracy of native-T1 mapping compared to LGE-TEI (AUC − 0.88, p < 0.001 in cMI, vs AUC − 0.83, p < 0.001 in aMI). Native-T1 performed better in cMI than aMI (p < 0.01). In cMI a segmental T1 threshold of 1085 ms differentiated viable from non-viable segments with a sensitivity 88% and specificity of 88% whereas a T1 of 1110 ms differentiated viable from nonviable with 79% sensitivity and 79% specificity in aMI. Native-T1 mapping correlates significantly with TEI thereby differentiating between normal, viable, and non-viable myocardium with distinctive T1 profiles in aMI and cMI. Native T1-mapping to detect MI performed better in cMI compared to aMI due to absence of myocardial oedema. Native-T1 mapping holds promise for viability assessment without the need for gadolinium-contrast agent.

Cardiac magnetic resonance imaging (CMR) characteristics in apical versus non-apical hypertrophic cardiomyopathy (HCM)

Methods Approximately 3,100 CMR scans were reviewed from our CMR registry (Jan 2014 to Mar 2015). comprehensive CMR protocol was used including cines, early and late gadolinium enhancement imaging. 114 consecutive HCM patients were identified. A Asymmetric HCM was defined as: septal to free wall thickness ratio of > 1.3; apical HCM as apical wall thickness of > 15 mm or apical to basal LV wall thicknesses ≥ 1.3-1.5; and concentric HCM as symmetrical hypertrophy of ventricular wall without any regional preferences. Non-apical HCM group (comprising of asymmetric and concentric phenotypes) were compared with apical HCM. Fisher’s exact t-test and unpaired t-test were performed for statistical significance. P-value < 0.05 was statistically significant. Univariate and multivariate logistic regression analyses were performed to determine the CMR predictors of apical HCM. Results The final study sample consisted of 104 patients with HCM with median age 60years (IQR = 54-70) and 70% male, (10 patients excluded due to uncertain diagnosis) 70% non-apical HCM; the remainder 30% apical HCM. In the non-apical HCM group, 5 patients had concentric HCM and the rest had asymmetric HCM. The. The mean maximum LV wall thickness, mean indexed LV mass, mean indexed stroke volume, prevalence of LVOTO and SAM were significantly greater in nonapical group. Table 1 The presence of LGE was high in both groups (>85%) and was not statistically different. The univariate predictors of apical HCM included maximum LV wall thickness, indexed stroke volume, LVOT obstruction whereas in the multivariate model maximum LV wall thickness remained the only significant predictor.

Remote myocardium is also affected in acute myocardial infarction: evidence from advanced CMR relaxometry

Methods 30 patients (mean age 61 ± 10years and 70% males) with STEMI and successful revascularisation by percutaneous coronary intervention were included. Each subject underwent clinical CMR at 1.5 T with T2 and T1 mapping (MOLLI) pre and post contrast (equilibrium contrast technique for extracellular volume (ECV) quantification) within 48hours of presentation. The T2 and pre and post contrast T1 values were evaluated in each of the 16 AHA myocardial segments.

Impact of cardiovascular magnetic resonance on management and clinical decision-making in patients presenting with chest pain, elevated troponin and unobstructed coronary artery

Background Management of patients presenting with chest pain, elevated troponin and unobstructed coronary artery is challenging. Cardiovascular magnetic resonance (CMR) can provide important diagnostic and prognostic information in this cohort. However, the evidence of impact of CMR on clinical management is lacking. We sought to evaluate the impact of CMR on diagnosis and clinical management in patients with chest pain, elevated troponin and unobstructed coronaries.

129 Impact of Cardiovascular Magnetic Resonance on Management and Clinical Decision-Making in Acute Hospitalised Patients

Background Cardiac Magnetic Resonance (CMR) is a valuable tool in the assessment of both ischaemic and non-ischaemic heart disease. The use of CMR in chronic cardiac conditions has already been demonstrated. However, evidence of the impact of CMR on the clinical management on the acute phase of hospital care, is scarce. We sought to evaluate the impact of CMR on diagnosis and clinical decision-making in acute hospitalised patients. Methods We looked at the 1 year registry data of 2481 consecutive scans (Jan 2014-Dec2014) at a large tertiary cardiothoracic center and identified 283 patients refered for inpatient CMR scan. CMR protocol included short axis and long axis cines, T2 weighted oedema sequences, early and late gadolinium enhancement (LGE) images. Definitions for “significant clinical impact” of CMR were pre-defined and data was collected from clinical records. Categories of significant clinical impact included change in pre-CMR diagnosis, influence on hospitalization period, change in medication, as well as influence on invasive medical procedures such as CABG, angiography and ICD implantation. Results Of the 283 patients, 8 (2.8%) were excluded due to poor image quality and/or incomplete scans, leaving a sample of 275 patients (66% male, mean age 59yrs) with mean ejection fraction of 46%+-19. Overall, CMR had a significant clinical impact on 68% of the patients. This included a completely new diagnosis in 27% of the patients, change in management in 31% and a total of 10% of patients had both a new diagnosis and a change in management (see Figure 2). CMR results led to invasive procedures on 27%, avoided invasive procedures on 16%, and had an influence on hospital discharge on 15% of the patients. 84% of the patients had echocardiography prior to CMR. CMR confirmed the echo diagnosis in 11%, complemented the echo findings by additing significant new information in 41% and changed the diagnosis made on echo in 30% of the cases. In a multivariable model that included clinical and imaging parameters, age and presence of LGE were the only independent predictor of “significant clinical impact” (LGE p-value. 007, OR 2.782, CI 1.328–5.828) (see Figure 1).Abstract 129 Figure 1 (A) Change in diagnosis after CMR in patients with chest pain; (B) Change in diagnosis after CMR in patients with shortness of breath; (C) Change in diagnosis after CMR in patients with syncope, arrhythmias and out of hospital cardiac arrest Conclusions CMR had a significant clinical impact on both management and diagnosis in 68% of acutely hospitalised patients. The presence of LGE was the best independent predictor of significant clinical impact following CMR.Abstract 129 Table 1 Sig. Odds Ratio 95% Conf. Interval Lower Upper Sex .486 .766 .361 1.622 Age .028 1.026 1.003 1.050 Troponin .469 1.000 1.000 1.000 LVEF .945 .999 .972 1.027 iEDV .827 1.001 .989 1.014 RWMA .053 2.440 .987 6.033 LGE .007 2.782 1.328 5.828 Oedema .672 .904 .566 1.444 Variable (s): Sex, Age, Troponin, iEDV, RWMA, LGE, Oedema