Abnormal release of cardiac biomarkers in the presence of myocardial oedema evaluated by cardiac magnetic resonance after uncomplicated revascularization procedures

AIMS

To analyse the association of myocardial oedema (ME), observed as high T2 signal intensity (HT2) in cardiac magnetic resonance imaging, with the release of cardiac biomarkers, ventricular ejection, and clinical outcomes after revascularization.

METHODS AND RESULTS

Patients with stable coronary artery disease with the indication for revascularization were included. Biomarker levels [troponin I (cTnI) and creatine kinase MB (CK-MB)] and T2-weighted and late gadolinium enhancement (LGE) images were obtained before and after the percutaneous or surgical revascularization procedures. The association of HT2 with the levels of biomarkers, with and without LGE, evolution of left ventricular ejection fraction (LVEF), and 5-year clinical outcomes were assessed. A total of 196 patients were divided into 2 groups: Group 1 (HT2, 40) and Group 2 (no HT2, 156). Both peak cTnI (8.9 and 1.6 ng/mL) and peak CK-MB values (44.7 and 12.1 ng/mL) were significantly higher in Group 1. Based on the presence of new LGE, patients were stratified into Groups A (no HT2/LGE, 149), B (HT2, 9), C (LGE, 7), and D (both HT2/LGE, 31). The peak cTnI and CK-MB values were 1.5 and 12.0, 5.4 and 44.7, 5.0 and 18.3, and 9.8 and 42.8 ng/mL in Groups A, B, C, and D, respectively, and were significantly different. The average LVEF decreased by 4.4% in Group 1 and increased by 2.2% in Group 2 (P = 0.057).

CONCLUSION

ME after revascularization procedures was associated with increased release of cardiac necrosis biomarkers, and a trend towards a difference in LVEF, indicating a role of ME in cardiac injury after interventions.

Myocardial tissue microstructure with and without stress-induced ischemia assessed by T1 mapping in patients with stable coronary artery disease

BACKGROUND

Stress-induced myocardial ischemia seems not to be associated with cardiovascular events. However, its effects on myocardial tissue characteristics remain under debate. Thus, we sought to assess whether documented stress-induced ischemia is associated with changes in myocardial microstructure evaluated by magnetic resonance native T1 map and extracellular volume fraction (ECV).

METHODS

This is a single-center, analysis of the previously published MASS V Trial. Multivessel patients with a formal indication for myocardial revascularization and with documented stress-induced ischemia were included in this study. Native T1 and ECV values evaluated by cardiac magnetic resonance imaging of ischemic and nonischemic myocardial segments at rest and after stress were compared. Myocardial ischemia was detected by either nuclear scintigraphy or stress magnetic cardiac resonance protocol.

RESULTS

Between May 2012 and March 2014, 326 prospective patients were eligible for isolated CABG or PCI and 219 were included in the MASS V trial. All patients underwent resting cardiac magnetic resonance imaging. Of a total of 840 myocardial segments, 654 were nonischemic segments and 186 were ischemic segments. Native T1 and ECV values of ischemic segments were not significantly different from nonischemic segments, both at rest and after stress induction. In addition, native T1 and ECV values of myocardial segments supplied by vessels with obstructive lesions were similar to those supplied by nonobstructive ones.

CONCLUSION AND RELEVANCE

In this study, cardiac magnetic resonance identified similar T1 mapping values between ischemic and nonischemic myocardial segments. This finding suggests integrity and stability of myocardial tissue in the presence of stress-induced ischemia.

BRASH Syndrome: A Case Report

Patient: Male, 76-year-old

Final Diagnosis: Cardiogenic shock

Symptoms: Lethargy

Medication:—

Clinical Procedure: N/A

Specialty: Cardiology

P598T1 mapping and myocardial extracellular volume assessed by cardiac magnetic resonance in diabetic patients with stable coronary artery disease

Background

T1 mapping is a quantitative technique of cardiac magnetic resonance (CMR) increasingly used for characterization of the myocardium. Type 2 diabetes mellitus (T2DM) may impact myocardial tissue structure, however studies that assessed this association using non-invasive methods have conflicting results.

Purpose

We sought to compare the tissue characteristics of the non-infarcted myocardium of patients with and without diabetes with multivessel CAD.

Methods

Patients with stable multivessel CAD and preserved left ventricular ejection fraction (LVEF), included in the MASS V trial, underwent contrast-enhanced CMR before revascularization procedures. Patients were stratified according to the T2DM diagnosis at baseline. Values of myocardial native T1, post-contrast T1 and extracellular volume fraction (ECV) were compared between diabetic and non-diabetic patients. Only myocardial tissue without late gadolinium enhancement were assessed.

Results

Of 155 patients studied, 67 (43%) were diabetic and 88 (57%) non-diabetic. Baseline characteristics were similiar between groups (age 70±10 vs 69±11; 69% vs 68% males; LVEF 65±13 vs 67±9). Mean Syntax score was 21.2±8.5 and 20.4±8.5 (p=0.52) in diabetic and non-diabetic, respectively. Myocardial native T1 values showed no diference in diabetic and non-diabetic (1013±67.9 vs 1015±61.4, p=0.72). However, in diabetic patients values of post-contrast T1 were significantly lower (482.2±43.8 vs 499.4±47.2, p=0.024) and ECV were higher (29.62±6.61 vs 27.08. ± 4.22, p=0.004). Multivariable analyses adjusted for age, sex, BMI, hypertension and Syntax score showed no differences in the results.

Figure1

Conclusion

In this study, T2DM was associated with higher ECV and lower post-contrast T1 values in the myocardial tissue. These findings suggest an increase in the myocardial intersticial matrix in patients with diabetes and stable multivessel CAD.

P1832Myocardial injury assessed by T1 mapping after on-pump and off-pump coronary artery bypass grafting. a pre-specified analysis of mass V trial

Background

Myocardial structural damage may occur during coronary artery bypass grafting (CABG) surgery and is identified by the significant release of cardiac biomarkers. However, the evidence of these structural myocardial changes after CABG by current imaging methods remains unknown. To evaluate myocardial structure, we used the T1 mapping of cardiac magnetic resonance (CMR) before and after on-pump and off-pump CABG.

Methods

Patients with multivessel coronary artery disease and preserved ventricular function were included and underwent on or off-pump CABG. CMR and T1 mapping were performed using the MOLLI technique (modified Look-Locker inversion-recovery). Values of native T1 and extracellular volume fraction (ECV) were compared before and after on and off-pump procedures.

Results

Of 110 eligible patients, 34 were excluded due to the presence of new late enhancement or edema. Of 76 patients remained, 32 (42%) underwent on-pump (Group A) and 44 (58%) off-pump CABG (Group B). All baseline characteristics were similar between groups, besides the Syntax Score that was higher in Group A (25 × 21, p=0.002). For group A, native T1 before and after procedures was 1013 ms (998–1043) and 1004 ms (793–1048), p=0.19, and ECV was 26.4 (23.9–27.6) and 31.2 (27.6–33.9), p<0.001. For group B, native T1 before and after procedures was 1015 ms (970–1044) and 992 ms (867–1051), p=0.003, and ECV 27.5 (25.3–29.9) and 30.3 (26.5–34.3), p=0.02. The comparison of native T1 difference before and after procedures between groups A and B was not significant (Delta T1 −9.8 (−102 to 51.8) × −25.4 (−119 to 51,2), p=0.87. However, the difference of ECV between groups was statistically significant (ECV Delta 3.8 (2.2 to 7.1) × 1.3 (−1.1 to 4.9), p=0.039, respectively, for groups A and B.

Figure 1

Conclusion

In this sample, T1 mapping identified significant myocardial structural changes in both surgical revascularization procedures. Additionally, a marked myocardial injury generated by ECV changes were observed after on-pump CABG.

P1835Application of SYNTAX score I, II and residual SYNTAX as predictors of long-term clinical outcomes after coronary artery bypass grafting

Background

The evaluation of coronary disease by SYNTAX score I (SSI) is used to grade coronary complexity. Following SSI, two other scores were developed: SYNTAX score II (SSII) and residual SYNTAX score (rSS). Nevertheless, there is still a lack of evidence about the prognostic significance of these scores among patients undergoing CABG.

Purpose

Our aim was to evaluate the relation of the SSI, SSII and rSS score with outcomes in a long-term follow-up after elective CABG.

Methods

This is a single center, registry-based study. Baseline SSI was calculated from patients undergoing CABG by interventional cardiologists. SSI results were considered as usual: <23, 23–32 and >32. SSII and rSRR were then calculated and categorized in tertiles: <21.4, 21.4–29.4 and >29.4 for SSII and 0, 1–5 and >5 for rSS. Primary outcome was a composite of overall death, myocardial infarction, additional revascularization, or stroke (MACCE).

Results

Data were obtained from 559 patients. Median follow-up was 6 years (IQR: 4.9–9.8) and 170 events were documented. The Kaplan-Meier curves (figure 1) showed significant differences of MACCE in higher SSI, SSII and rSS (p=0.039, 0.033, <0.001 respectively). After multivariate adjustment, rSS, ejection fraction (EF) and age were found to be independent predictors of MACCE (p<0.001, 0.034 and 0.006, respectively).

Figure 1

Conclusion

In this sample SSI, II and residual were associated with the occurrence of events. However, just the rSS remained an independent predictor of MACCE together with age and EF.