Rodrigo Morel Vieira de Melo

Hypotheses, rationale, design, and methods for prognostic evaluation of cardiac biomarker elevation after percutaneous and surgical revascularization in the absence of manifest myocardial infarction. A comparative analysis of biomarkers and cardiac magnetic resonance. The MASS-V Trial

BackgroundAlthough the release of cardiac biomarkers after percutaneous (PCI) or surgical revascularization (CABG) is common, its prognostic significance is not known. Questions remain about the mechanisms and degree of correlation between the release, the volume of myocardial tissue loss, and the long-term significance. Delayed-enhancement of cardiac magnetic resonance (CMR) consistently quantifies areas of irreversible myocardial injury. To investigate the quantitative relationship between irreversible injury and cardiac biomarkers, we will evaluate the extent of irreversible injury in patients undergoing PCI and CABG and relate it to postprocedural modifications in cardiac biomarkers and long-term prognosis.Methods/DesignThe study will include 150 patients with multivessel coronary artery disease (CAD) with left ventricle ejection fraction (LVEF) and a formal indication for CABG; 50 patients will undergo CABG with cardiopulmonary bypass (CPB); 50 patients with the same arterial and ventricular condition indicated for myocardial revascularization will undergo CABG without CPB; and another 50 patients with CAD and preserved ventricular function will undergo PCI using stents. All patients will undergo CMR before and after surgery or PCI. We will also evaluate the release of cardiac markers of necrosis immediately before and after each procedure. Primary outcome considered is overall death in a 5-year follow-up. Secondary outcomes are levels of CK-MB isoenzyme and I-Troponin in association with presence of myocardial fibrosis and systolic left ventricle dysfunction assessed by CMR.DiscussionThe MASS-V Trial aims to establish reliable values for parameters of enzyme markers of myocardial necrosis in the absence of manifest myocardial infarction after mechanical interventions. The establishments of these indices have diagnostic value and clinical prognosis and therefore require relevant and different therapeutic measures. In daily practice, the inappropriate use of these necrosis markers has led to misdiagnosis and therefore wrong treatment. The appearance of a more sensitive tool such as CMR provides an unprecedented diagnostic accuracy of myocardial damage when correlated with necrosis enzyme markers. We aim to correlate laboratory data with imaging, thereby establishing more refined data on the presence or absence of irreversible myocardial injury after the procedure, either percutaneous or surgical, and this, with or without the use of cardiopulmonary bypass.

Utilidade clínica da angiografia coronariana em pacientes com disfunção ventricular esquerda

BACKGROUND Performing a coronary angiography in patients with heart failure of unknown etiology is often justified by the diagnostic assessment of ischemic heart disease. However, the clinical benefit of this strategy is not known. OBJECTIVE To evaluate the prevalence of ischemic heart disease by angiographic criteria in patients with heart failure and reduced ejection fraction of unknown etiology, as well as its impact on therapy decisions. METHODS Consecutive outpatients with heart failure and systolic dysfunction, who had an indication for coronary angiography to clarify the etiology of heart disease were assessed from 1 January 2009 to December 31, 2010. Patients diagnosed with coronary artery disease, positive serology for Chagas disease, congenital heart disease, valve disease or patients undergoing cardiac transplantation were excluded from the analysis. The sample was divided into two groups according to the indication for catheterization. Group-1: Symptomatic due to angina or heart failure. Group-2: Presence of > 2 risk factors for coronary artery disease RESULTS One hundred and seven patients were included in the analysis, with 51 (47.7%) patients in Group 1 and 56 (52.3%) in Group 2. The prevalence of ischemic heart disease was 9.3% (10 patients), and all belonged to Group 1 (p = 0.0001). During follow-up, only 4 (3.7%) were referred for CABG; 3 (2.8%) patients had procedure-related complications. CONCLUSION In our study, coronary angiography in patients with heart failure and systolic dysfunction of unknown etiology, although supported by current guidelines, did not show benefits when performed only due to the presence of risk factors for coronary artery disease.

Comparison between off-pump and on-pump coronary artery bypass grafting in patients with severe lesions at the circumflex artery territory: 5-year follow-up of the MASS III trial.

OBJECTIVES The technical difficulty in the revascularization of the circumflex artery territory with off-pump surgery may compromise the outcome of this method in clinical follow-up. We aimed to evaluate cardiac events in patients with stable coronary artery disease and severe obstruction of the circumflex system, undergoing coronary artery bypass grafting (CABG) with or without cardiopulmonary bypass. METHODS MASS III was a single-centre study that evaluated 308 patients with multivessel coronary artery disease randomized to on-pump (153) or off-pump (155) CABG. Of this total, 260 (84.4%) patients had, on coronary angiography, at least one 70% obstruction in the circumflex territory (141 on-pump and 119 off-pump). The combined outcome was death, myocardial infarction, target vessel revascularization (angioplasty or surgery) or hospitalization for cardiac causes. Variables with possible associations (P < 0.1) were included in the multivariate analysis. RESULTS The two groups were well matched for demographics and clinical and angiographic characteristics. After 5 years of follow-up, off-pump CABG had higher combined events than on-pump had: 25 (21%) vs 17 (12%), hazard ratio 1.88, 95% confidence interval 1.02-3.48, P = 0.041. In the multivariate model with the inclusion of the following variables: age (P = 0.09) and complete revascularization (P = 0.68), off-pump surgery remained as a predictor of combined events in 5 years, P = 0.03. CONCLUSIONS In patients with multivessel coronary artery disease and severe lesions in the circumflex territory, off-pump coronary artery bypass surgery resulted in a higher incidence of cardiac events at 5-year follow-up. CLINICAL TRIAL REGISTRATION NUMBER ISRCTN59539154 (http://www.controlled-trials.com).

Biomarker release after percutaneous coronary intervention in patients without established myocardial infarction as assessed by cardiac magnetic resonance with late gadolinium enhancement: VIEIRA DE MELO et al.

This study aimed to evaluate the amount and pattern of cardiac biomarker release after elective percutaneous coronary intervention (PCI) in patients without evidence of a new myocardial infarction (MI) after the procedure as assessed by cardiac magnetic resonance (CMR) with late gadolinium enhancement (LGE).

Significant elevation of biomarkers of myocardial necrosis after coronary artery bypass grafting without myocardial infarction established assessed by cardiac magnetic resonance

Abstract The release of myocardial necrosis biomarkers after off-pump coronary artery bypass grafting (OPCAB) frequently occurs. However, the correlation between biomarker release and the diagnosis of procedure-related myocardial infarction (MI) (type 5) has been controversial. This study aimed to evaluate the amount and pattern of cardiac biomarker release after elective OPCAB in patients without evidence of a new MI on cardiac magnetic resonance (CMR) imaging with late gadolinium enhancement (LGE). Patients with normal baseline cardiac biomarkers referred for elective OPCAB were prospectively included. CMR with LGE was performed in all patients before and after interventions. Measurements of troponin I (cTnI) and creatine kinase MB fraction (CK-MB) were systematically performed before and after the procedure. Patients with new LGE on the postprocedure CMR were excluded. All of the 53 patients without CMR evidence of a procedure-related MI after OPCAB exhibited a cTnI elevation peak above the 99th percentile. In 48 (91%), the peak value was >10 times this threshold. However, 41 (77%) had a CK-MB peak above the limit of the 99th percentile, and this peak was >10 times the 99th percentile in only 7 patients (13%). The median peak release of cTnI was 0.290 (0.8–3.7) ng/mL, which is 50-fold higher than the 99th percentile. In contrast with CK-MB, considerable cTnI release often occurs after an elective OPCAB procedure, despite the absence of new LGE on CMR.

Abnormal elevation of myocardial necrosis biomarkers after coronary artery bypass grafting without established myocardial infarction assessed by cardiac magnetic resonance

BackgroundThe diagnosis of peri-procedural myocardial infarction is complex, especially after the emergence of high-sensitivity markers of myocardial necrosis.MethodsIn this study, patients with normal baseline cardiac biomarkers and formal indication for elective on-pump coronary bypass surgery were evaluated. Electrocardiograms, cardiac biomarkers, and cardiac magnetic resonance imaging with late gadolinium enhancement were performed before and after procedures. Myocardial infarction was defined as more than ten times the upper reference limit of the 99th percentile for troponin I and for creatine kinase isoform (CK-MB) and by the findings of new late gadolinium enhancement on cardiac magnetic resonance. We assessed the release of cardiac biomarkers in patients with no evidence of myocardial infarction on cardiac magnetic resonance.ResultsOf 75 patients referred for on-pump coronary bypass surgery, 54 (100%) did not have evidence of myocardial infarction on cardiac magnetic resonance. However, all had a peak troponin I above the 99th percentile; 52 (96%) had an elevation 10 times higher than the 99th percentile. Regarding CK-MB, 54 (100%) patients had a peak CK-MB above the 99th percentile limit, and only 13 (24%) had an elevation greater than 10 times the 99th percentile. The median value of troponin I peak was 3.15 (1.2 to 3.9) ng/mL, which represented 78.7 times the 99th percentile.ConclusionIn this study, different from CK-MB findings, troponin was significantly increased in the absence of myocardial infarction on cardiac magnetic resonance. Thus, CK-MB was more accurate than troponin I for excluding procedure-related myocardial infarction. These data suggest a higher troponin cutoff for the diagnosis of coronary bypass surgery related myocardial infarction.Clinical trial registrationhttp://www.isrctn.com/ISRCTN09454308. Registered 08 May 2012.

Utilidade clínica da angiografia coronária e da ressonância nuclear magnética no diagnóstico da cardiomiopatia isquêmica

BACKGROUND: The diagnosis of ischemic cardiomyopathy is frequently difficult. Coronary angiography (CA) is limited because it is invasive and the evaluation is exclusively anatomic. Cardiac magnetic resonance imaging (MRI) with late gadolinium enhancement (LGE) measures patterns of myocardial fibrosis caused by ischemia. However, LGE does not detect ischemia that does not result in fibrosis. Thus, a thorough clinical evaluation by a cardiologist seems to be the most effective option for diagnosis. The aim of this study was to evaluate CA and LGE as complementary methods for the diagnosis of ischemic cardiomyopathy in patients with systolic heart failure of unknown etiology. METHODS: Patients with systolic heart failure, left ventricle ejection fraction < 45% and unknown etiology after initial non-invasive evaluation were submitted to CA and MRI with LGE to define the etiology of the disease. Patient evaluation by two cardiologists was the gold standard for the diagnosis of ischemic cardiomyopathy. RESULTS: Twenty-four patients were included. The sensitivity to detect ischemic cardiomyopathy was 0.45 for CA vs. 0.81 for LGE. The specificity was 1.0 for CA vs. 0.84 for LGE. The positive predictive value was 1.0 vs. 0.81 and the negative predictive value was 0.68 vs. 0.84 for CA and LGE, respectively. LGE accuracy was superior to CA accuracy (0.83 vs. 0.75). CONCLUSIONS: LGE was more sensitive than CA to evaluate the etiology of ventricular dysfunction, whereas CA was more specific. The diagnosis of ischemic cardiomyopathy using each one of the methods separately presented limitations.

Clinical Use of Coronary Angiography and Magnetic Nuclear Resonance Imaging in the Diagnosis of Ischemic Cardiomyopathy

ABSTRACT Background The diagnosis of ischemic cardiomyopathy is frequently difficult. Coronary angiography (CA) is limited because it is invasive and the evaluation is exclusively anatomic. Cardiac magnetic resonance imaging (MRI) with late gadolinium enhancement (LGE) measures patterns of myocardial fibrosis caused by ischemia. However, LGE does not detect ischemia that does not result in fibrosis. Thus, a thorough clinical evaluation by a cardiologist seems to be the most effective option for diagnosis. The aim of this study was to evaluate CA and LGE as complementary methods for the diagnosis of ischemic cardiomyopathy in patients with systolic heart failure of unknown etiology. Methods Patients with systolic heart failure, left ventricle ejection fraction Results Twenty-four patients were included. The sensitivity to detect ischemic cardiomyopathy was 0.45 for CA vs. 0.81 for LGE. The specificity was 1.0 for CA vs. 0.84 for LGE. The positive predictive value was 1.0 vs. 0.81 and the negative predictive value was 0.68 vs. 0.84 for CA and LGE, respectively. LGE accuracy was superior to CA accuracy (0.83 vs. 0.75). Conclusions LGE was more sensitive than CA to evaluate the etiology of ventricular dysfunction, whereas CA was more specific. The diagnosis of ischemic cardiomyopathy using each one of the methods separately presented limitations.