Quantitative Assessment of Strain and Strain Rate by Velocity Vector Imaging During Dobutamine Stress Echocardiography to Predict Outcome in Patients With Left Bundle Branch Block

The role of stress echocardiography in the evaluation of coronary artery disease and myocardial ischemia in women

Considering the unfavorable prognosis of women with ischemic heart disease, an aggressive but safe approach to evaluate women presenting with chest pain is warranted so that coronary artery disease (CAD) can be identified and treated early. Stress echocardiography (SE) has matured into an invaluable technique for the noninvasive detection of obstructive epicardial CAD. Its versatility, accuracy, safety, noninvasiveness, and lack of radiation exposure make SE an attractive technique to apply to the assessment of women with known or suspected heart disease. This article focuses on the current evidence supporting the role of SE in the assessment of CAD and myocardial ischemia in women.

Non-invasive assessment of coronary artery disease in patients with left bundle branch block

There is a high prevalence of coronary artery disease (CAD) in patients with left bundle branch block (LBBB); however there are many other causes for this electrocardiographic abnormality. Non-invasive assessment of these patients remains difficult, and all commonly used modalities exhibit several drawbacks. This often leads to these patients undergoing invasive coronary angiography which may not have been necessary. In this review, we examine the uses and limitations of commonly performed non-invasive tests for diagnosis of CAD in patients with LBBB.

Prevalence and prognostic value of subclinical left ventricular systolic dysfunction by global longitudinal strain in a community-based cohort

AIMS

Global longitudinal strain (GLS) assessed by speckle-tracking echocardiography has been proposed as a parameter able to reflect early changes in left ventricular systolic function at a stage when left ventricular ejection fraction (LVEF) is still normal. This study aimed at assessing prevalence and prognostic value of left ventricular systolic dysfunction (LVSD) assessed by echocardiographic speckle-tracking GLS in a community-based cohort.

METHODS AND RESULTS

Participants from the community-based prospective Northern Manhattan Study underwent two-dimensional transthoracic echocardiography as part of the Cardiovascular Abnormalities and Brain Lesions study. Left ventricular systolic function was assessed by LVEF and speckle-tracking GLS. Subjects were followed annually (mean = 4.8 ± 1.5 years) and incident vascular events (ischaemic stroke, myocardial infarction, and vascular death) were reviewed and adjudicated. Of the 708 study participants, 114 (16.1%) had abnormal GLS but normal LVEF (GLS-LVSD), 30 (4.2%) had abnormal LVEF (LVEF-LVSD), and 564 (79.7%) had normal GLS and LVEF (no-LVSD). In multivariate analysis, risk of events was significantly greater in GLS-LVSD [adjusted hazard ratio (HR) = 2.39, 95% confidence interval (CI) = 1.20-4.77] and in LVEF-LVSD (adjusted HR = 3.51, 95% CI = 1.25-9.88) compared with no-LVSD. Among participants with normal LVEF, lower GLS was significantly associated with events (adjusted HR/unit decrease = 1.15, 95% CI = 1.03-1.28) whereas LVEF was not (adjusted HR/unit decrease = 1.01, 95% CI = 0.94-1.07). The GLS prognostic value was incremental to risk factors and LVEF both in the overall population (chi-square change = 7.406, P = 0.006) and in participants with normal LVEF (chi-square change = 6.357, P = 0.012).

CONCLUSION

In a community-based cohort, GLS-LVSD was four times more frequent than LVEF-LVSD. GLS-LVSD was a powerful and independent predictor of cardiovascular events. Left ventricular function assessment by GLS may improve cardiovascular risk stratification in subjects with normal LVEF.

Difficult ECGs in STEMI: lessons learned from serial sampling of pre- and in-hospital ECGs

Prehospital interpretation of electrocardiograms (ECGs) is crucial to ensure early diagnosis and optimal treatment of patients with ST elevation myocardial infarction (STEMI). Recognition of ST-segment elevations (STE) by qualified personnel in the prehospital phase has successfully reduced the delay from the first medical contact to reperfusion. A few other ECG patterns without true STE, referred to as "STEMI equivalents", bear the same prognostic significance, reflect imminent or ongoing transmural ischemia, but are less easily identified. Hyperacute T waves, de Winter ST-T complex, Wellens' syndrome, and posterior STEMI, as well as myocardial infarction in the presence of left bundle branch block, paced rhythm or left ventricular hypertrophy, among others are diagnostic challenges. This article reviews some critical examples of ischemic ECG patterns that may be ephemeral, misinterpreted by medical staff or not identified by automated ECG algorithms, and it emphasizes the importance of serial ECG acquisition.

The changing paradigm of stress echocardiography: risk stratification, prognosis, and future directions

The use of stress echocardiography has undergone considerable evolution in the past 3 decades. Although stress echocardiography was first introduced as a noninvasive diagnostic tool for determining the presence or absence of coronary artery disease (CAD), it later served a prognostic role as well. The importance of stress echocardiography in risk stratification and prognosis is substantially undervalued by clinicians. The identification of patients at risk for future cardiac events has become a primary objective in noninvasive evaluation of patients with suspected or known CAD. In particular, the ability of stress echocardiography to identify patients at low (< 1%), intermediate (1%-5%), or high (> 5%) risk for future cardiac events is essential to decision making in patient management. Moreover, previous studies have conclusively demonstrated the incremental prognostic value of stress echocardiography over clinical and treadmill exercise data in predicting future cardiac events. This article presents a primarily single-center experience of retrospective and observational studies that address the current role of stress echocardiography and summarize its use for risk stratification, prognosis, and determining clinical outcomes, as well as cost-effective integration of such information in patient management decision making.