Prognostic value of dobutamine stress echocardiography in octogenarians

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.

Prognostic value of Doppler echocardiographic-derived coronary flow velocity reserve of left anterior descending artery in octogenarians with stress echocardiography negative for wall motion criteria

AIMS

Doppler-derived coronary flow velocity reserve (CFVR) of left anterior descending (LAD) artery is an effective tool to predict overall mortality. The aim was to investigate the capability of CFVR to predict outcome in an unselected cohort of patients older than 80 years having stress echo negative by wall motion criteria.

METHODS AND RESULTS

The study group refers to 369 patients aged > 80 years (156 men; mean age 83 ± 2 years) who had undergone dipyridamole stress echocardiography with CFVR assessment of LAD artery of known (n = 144) or suspected (n = 225) coronary artery disease. Stress echocardiography was negative for wall motion criteria in all cases. Mean CFVR was 2.07 ± 0.53. During a median follow-up of 21 months, there were 62 major adverse cardiac events (MACEs; 45 deaths and 17 non-fatal myocardial infarctions). With a receiver operating characteristic analysis, a CFVR of ≤ 1.93 was the best cut-off for predicting mortality and MACE. At individual patient analysis, 152 (41%) subjects had a CFVR of < 1.93. Annual mortality was 9.8% in patients with CFVR <1.93 and 3.7% in those with CFVR > 1.93 (P = 0.001); an annual MACE rate was 14.8% in the former and 4.5% in the latter (P < 0.0001). Of 15 clinical and echocardiographic parameters analysed, CFVR ≤ 1.93 [hazard ratio (HR) = 2.17, 95% CI 1.14-4.10] and resting wall motion abnormality (RWMA; HR = 2.60; 95% CI 1.35-5.00) were multivariable indicators of mortality. Moreover, CFVR ≤ 1.93 (HR = 2.69, 95% CI 1.56-4.67), and RWMA (HR = 2.38; 95% CI 1.31-4.33) were also strong independent predictors of MACEs. At incremental analysis, CFR ≤ 1.93 added prognostic information over clinical evaluation and RWMA when both mortality and MACE were taken as clinical end points.

CONCLUSIONS

A reduced CFVR of LAD artery is a strong and independent indicator of both mortality and MACE, adding prognostic information over clinical evaluation and RWMA. Conversely, a preserved CFVR predicts a favourable outcome particularly in subjects with no RWMA.

Cardiac imaging in the geriatric population: what do we think we know, and what do we need to learn?

Cardiac imaging plays an important role in coronary artery disease (CAD), congestive heart failure (HF) and valvular heart disease (VHD) in the elderly. Imaging defines the structure and function of the cardiac system, refining the understanding of patients' anatomy and physiology and informing a host of clinical care decisions, including prognosis. Yet there is a paucity of evidence to guide the rational use of many imaging modalities in patients of advanced age, a population with considerable clinical heterogeneity, high prevalence and burden of cardiovascular disease (CVD) and atypical presentations of CVD. This paper discusses important considerations for cardiac imaging for older adults, particularly in regard to CAD, VHD and HF, and then presents domains for future research to produce data that would inform clinical care guidelines, appropriate use criteria and imaging lab protocols to address the unique needs of the fast-growing elderly population.

Stress echocardiography in the ED: diagnostic performance in high-risk subgroups

PURPOSE

To assess stress-echo (SE) diagnostic performance in patients presenting to the emergency department (ED) with spontaneous chest pain, especially in subgroups in which exercise ECG diagnostic performance has been questioned (women, elderly, history of coronary artery disease).

METHODS

Between June 2008 and May 2011, 474 patients with an episode of spontaneous chest pain, non-diagnostic electrocardiogram and negative cardiac necrosis markers underwent SE. Patients with inducible ischemia (Isch) were asked to undergo coronary angiography. Patients with negative SE were discharged and contacted by telephone at least 6 months after discharge, to ascertain the occurrence of new cardiac events.

MAIN FINDINGS

Exercise stress-echo (ESE) was employed in 270 patients and dobutamine (DSE) in 218 (including 14 with inconclusive ESE); a diagnosis of coronary artery disease (CAD) was confirmed or excluded in 434 (92%) patients. SE was negative for Isch in 318 patients (206 ESE and 112 DSE) and positive in 132. During follow-up, patients with negative SE had 4 cardiac events. SE showed: sensitivity 90%, specificity 92%, positive predictive value 78% and negative predictive value 97%. Sensitivity was comparable between patients aged < or ≥70 years (84 vs 94%) and between gender (89 vs 96%), but lower in patients with known CAD (88 vs 94%, P < .05); specificity was comparable regardless of age (94 vs 99%) and presence of CAD (97 vs 91%), but was lower among women (87 vs 96%, P < .05).

CONCLUSIONS

SE had a very good diagnostic performance in ED patients with suspected Isch, both overall and in selected high-risk groups.

Meta-analysis of optimal risk stratification in patients >65 years of age

This meta-analysis evaluated the optimal noninvasive strategy for cardiac risk assessment of patients >65 years of age with known or suspected coronary artery disease using the available literature. Patients >65 years of age constitute a growing proportion of the population and have higher cardiovascular morbidity and mortality, but an optimal strategy to predict the risk of cardiac events in this group is unknown. A systematic search of MEDLINE was performed for cohort studies of ≥100 patients >65 years old with ≥12 months of follow-up that reported cardiac death and/or nonfatal myocardial infarction after any of stress myocardial perfusion imaging (MPI), stress echocardiography, or exercise tolerance testing (ETT) for known or suspected coronary artery disease. Pooled annualized event rates were calculated for each technique. Summary odds ratios (ORs) between normal and abnormal test results were calculated using a random-effects model. Seventeen studies (MPI 7, stress echocardiography 7, ETT 3) in 13,304 patients (mean age 75.5 years) were included. Abnormal compared to normal stress MPI (OR 11.8, 95% confidence interval [CI] 7.5 to 18.7) and stress echocardiography (OR 3.2, 95% CI 2.6 to 3.9) accurately stratified risk in patients. However, patients with abnormal and normal ETT results had similar cardiac event rates (OR 3.1, 95% CI 0.8 to 11.5). In conclusion, stress imaging with MPI or stress echocardiography effectively stratified risk in patients, whereas ETT alone did not.