Diagnostic Accuracy of Cardiac Magnetic Resonance Imaging in the Evaluation of Newly Diagnosed Heart Failure With Reduced Left Ventricular Ejection Fraction

Validation of electrocardiographic criteria for identifying left ventricular dysfunction in patients with previous myocardial infarction

Background

Eleven criteria correlating electrocardiogram (ECG) findings with reduced left ventricular ejection fraction (LVEF) have been previously published. These have not been compared head‐to‐head in a single study. We studied their value as a screening test to identify patients with reduced LVEF estimated by cardiac magnetic resonance (CMR) imaging.

Methods

ECGs and CMR from 548 patients (age 61 + 11 years, 79% male) with previous myocardial infarction (MI), from the DETERMINE and PRE‐DETERMINE studies, were analyzed. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of each criterion for identifying patients with LVEF ≤ 30% and ≤ 40% were studied. A useful screening test should have high sensitivity and NPV.

Results

Mean LVEF was 40% (SD = 11%); 264 patients (48.2%) had LVEF ≤ 40%, and 96 patients (17.5%) had LVEF ≤ 30%. Six of 11 criteria were associated with a significant lower LVEF, but had poor sensitivity to identify LVEF ≤ 30% (range 2.1%–55.2%) or LVEF ≤ 40% (1.1%–51.1%); NPVs were good for LVEF ≤ 30% (range 82.8%–85.9%) but not for LVEF ≤ 40% (range 52.1%–60.6%). Goldberger's third criterion (RV4/SV4 < 1) and combinations of maximal QRS duration > 124 ms + either Goldberger's third criterion or Goldberger's first criterion (SV1 or SV2 + RV5 or RV6 ≥ 3.5 mV) had high specificity (95.4%–100%) for LVEF ≤ 40%, although seen in only 48 (8.8%) patients; predictive values were similar on subgroup analysis.

Conclusions

None of the ECG criteria qualified as a good screening test. Three criteria had high specificity for LVEF ≤ 40%, although seen in < 9% of patients. Whether other ECG criteria can better identify LV dysfunction remains to be determined.

Accuracy of cardiac magnetic resonance imaging to rule out significant coronary artery disease in patients with systolic heart failure of unknown aetiology: Single-centre experience and comprehensive meta-analysis

BACKGROUND

Coronary artery disease (CAD) is the leading cause of systolic heart failure (HF). Cardiac magnetic resonance imaging (CMR) is a non-invasive technique that detects a myocardial infarction scar as subendocardial or transmural late gadolinium enhancement (st-LGE).

AIM

We sought to evaluate whether a lack of st-LGE could rule out CAD in new-onset systolic HF of unknown aetiology.

METHODS

We included 232 consecutive patients with new-onset HF and left ventricular ejection fraction ≤35% who underwent both coronary angiography and CMR to assess HF aetiology. CAD was defined as the presence of coronary artery stenosis≥50% on a coronary angiogram. We assessed sensitivity, specificity, and positive and negative likelihood ratios (PLR and NLR) of the presence of st-LGE to detect underlying CAD. A complementary meta-analysis of 11 studies (including ours) was also performed.

RESULTS

In our study, 49 (21.1%) patients had CAD. The sensitivity and specificity of the presence of st-LGE to detect CAD were 69 and 92%, respectively. PLR and NLR were 8.47 and 0.33, respectively. In the meta-analysis, 1227 patients were included, and the prevalence of CAD ranged from 19.2 to 68.3%. Sensitivity, specificity, PLR and NLR were 87% (95% confidence interval [CI] 0.80-0.92), 93% (95% CI 0.89-0.96), 12.91 (95% CI 7.70-21.64) and 0.14 (95% CI 0.09-0.22), respectively. Altogether, 55 patients presented CAD with no st-LGE; inversely, 75 patients presented st-LGE with no CAD.

CONCLUSION

With a CMR specificity of 93%, the absence of st-LGE rules out significant underlying CAD in patients with systolic HF of unknown aetiology in most cases.

Comparison of Clinical and Electrocardiographic Predictors of Ischemic and Nonischemic Cardiomyopathy During the Initial Evaluation of Patients With Reduced (≤40%) Left Ventricular Ejection Fraction

Invasive coronary angiography is routinely performed during the initial evaluation of patients with suspected cardiomyopathy with reduced left ventricular function. Clinical and electrocardiographic (ECG) data may accurately predict ischemic cardiomyopathy (IC). Medical records of adults referred for coronary angiography for evaluation of left ventricular ejection fraction ≤40% from 2010 to 2014 were retrospectively reviewed. Patients with myocardial infarction (MI), previous coronary revascularization, cardiac surgery, or left-sided valvular disease were excluded. IC was defined as ≥70% diameter stenosis of the left main, proximal left anterior descending, or involvement of ≥2 epicardial coronary arteries. A risk model was developed from logistic regression coefficients, with a dichotomous cut-point based on the maximal Youden's index from the receiver-operating characteristic curve. A total of 273 patients met study inclusion criteria. Mean age was 56.8 ± 11.6 and 68.1% were men. IC was identified in 41 patients (15%). Patients with IC were more likely to have ECG evidence of Q-wave MI (34% vs 13%, p <0.001) and less likely to have left bundle branch block (2% vs 15%, p = 0.03) than non-IC. A model including age, hypertension, diabetes mellitus, tobacco use, ECG evidence of ST or T-wave abnormalities concerning for ischemia, and previous Q-wave MI, yielded a 95% negative predictive value for IC. In conclusion, at an urban referral hospital, the prevalence of IC was low. Left bundle branch block on electrocardiography was rarely associated with IC. A risk score incorporating clinical and ECG abnormalities identified patients at a low likelihood for IC.

Recent Advances in Biomarker Discovery — from Serum to Imaging-based Biomarkers for a Complex Assessment of Heart Failure Patients

Over the last years, a vast majority of serum biomarkers and imaging techniques have been used alone or combined in the diagnosis, management and prognosis of numerous pathologies. This review provides a brief insight into the novelties from the last 6 years (2010–2016) regarding serum and imaging markers in heart failure (HF). New information about natriuretic peptides (NPs), soluble ST2 (Sst2), growth differentiation factor 15 (GDF-15), myeloperoxidase (MPO), C-reactive protein (CRP), procalcitonin (PCT), troponins (Tns), myoglobin (Mb), galectin-3 (Gal-3), micro ribonucleic acids (microRNAs) and long non-coding ribonucleic acids (IncRNAs), copectin and cardiac magnetic resonance (CMR) measurements were summarized in this review in order to guide the practitioner.