Applicability of Echocardiographic Strict Negative Criteria for Suspected Infective Endocarditis

Echocardiography is the cornerstone imaging technique in the diagnosis of infective endocarditis (IE) but is often misused in clinical practice. Recently, strict negative criteria have been proposed to avoid unnecessary follow-up echocardiograms. We aimed to evaluate the use of echocardiography in real-world clinical daily practice and the usefulness of these criteria in the diagnosis of IE. We retrospectively retrieved every echocardiogram performed in our center for suspected IE between 2014 and 2018, including 905 transthoracic echocardiograms (TTEs). Of these, 451 (49.8%) fulfilled the strict negative criteria (group 1). In this group, IE was seldom diagnosed (n = 4, 0.9%). In 338 patients (37.4%) no signs of IE were evident, but they did not fulfill the strict negative criteria (group 2). A follow-up echocardiogram and definitive diagnosis of IE were more frequent (n = 48, 14.2% and n = 20, 5.9%). Finally, in 116 patients (12.8%) the initial TTE showed typical or suggestive signs of IE, in whom the diagnosis was confirmed in 48 patients (41.4%). A definitive diagnosis of IE was established in a minority of the study population (n = 72, 8%). Only 1 readmission for underdiagnosis of IE was noted on group 2. We conclude that in a real-life setting only a minority of patients in whom IE was suspected had a definitive diagnosis. An initial TTE for suspected IE fulfilling the strict negative criteria predicts both a low probability of requesting a follow-up study and of a definitive diagnosis of IE.

Exercise ECG Testing and Stress Cardiac Magnetic Resonance for Risk Prediction in Patients With Chronic Coronary Syndrome

PURPOSE

Vasodilator stress cardiac magnetic resonance (VS-CMR) has become crucial in the workup of patients with known or suspected chronic coronary syndrome (CCS). Whether traditional exercise ECG testing (ExECG) contributes prognostic information beyond VS-CMR is unclear.

METHODS

We retrospectively included 288 patients with known or suspected CCS who had undergone ExECG and subsequent VS-CMR in our institution. Clinical, ExECG, and VS-CMR variables were recorded. We defined the serious adverse events (SAE) as a combined endpoint of acute coronary syndrome, admission for heart failure, or all-cause death.

RESULTS

During a mean follow-up of 4.2 ± 2.15 yr, we registered 27 SAE (15 admissions for acute coronary syndrome, eight admissions for heart failure, and four all-cause deaths). Once adjusted for clinical, ExECG, and VS-CMR parameters associated with SAE, the only independent predictors were HRmax in ExECG (HR = 0.98: 95% CI, 0.96-0.99; P = .01) and more extensive stress-induced perfusion defects (PDs, number of segments) in VS-CMR (HR = 1.19: 95% CI, 1.07-1.34; P < .01). Adding HRmax significantly improved the predictive power of the multivariable model for SAE, including PDs (continuous reclassification improvement index: 0.47: 95% CI, 0.10-0.81; P < .05). The annualized SAE rate was 1% (if PD < 2 segments and HRmax > 130 bpm), 2% (if PD < 2 segments and HRmax ≤ 130 bpm), 3.2% (if PD ≥ 2 segments and HRmax > 130 bpm), and 6.3% (if PD ≥ 2 segments and HRmax ≤ 130 bpm), P < .01, for the trend. In patients on β-blocker therapy, however, only PDs in VS-CMR, but not HRmax, predicted SAE.

CONCLUSIONS

We conclude that ExECG contributes significantly to prognostic information beyond VS-CMR in patients with known or suspected CCS.