The clinical impact of contemporary stress echocardiography in morbid obesity for the assessment of coronary artery disease.

OBJECTIVE: Non-invasive cardiac imaging may suffer from poor image quality in morbidly obese individuals. This study aimed to determine the clinical value of contemporary stress echocardiography (SE) in morbidly obese patients referred for assessment of suspected coronary artery disease (CAD). METHODS: This prospective, multicentre observational study was conducted in two district hospitals and one tertiary centre in London, UK. Individuals with body mass index ≥35 kg/m(2) referred for SE were evaluated. The percentage of patients with obstructive CAD on coronary angiography, following abnormal SE, was assessed. Patient outcomes were determined with follow-up for the composite end-point of all-cause mortality, myocardial infarction and late revascularisation. RESULTS: Over a 13-month period, 209 morbidly obese patients underwent SE, and contrast agent was used in 96% of patients. A diagnostic result was obtained in 200/209 (96%) patients. Of 32 (15%) patients with inducible ischaemia, 25 underwent angiography, 22 (88%) had corresponding significant CAD and, of these, 16 (77%) underwent revascularisation. Conversely, only 2/157 patients (1.3%) with normal SE underwent angiography, and none underwent revascularisation. Over a mean follow-up period of 17.8±5.4 months, there were nine events. The annualised cardiac event rate after a normal SE was 0.95%. Events were more frequent in patients with inducible ischaemia versus those without ischaemia (5/32 (15.6%) vs 4/153 (2.6%); p=0.002). Ejection fraction <50% (HR 9.5; 95% CI 2.4 to 38.0; p=0.002) and inducible ischaemia (HR 9.4; 95% CI 2.5 to 35.8; p=0.001) were predictors of outcome on univariable Cox regression analysis. CONCLUSIONS: Contemporary SE has excellent feasibility and positive predictive value and resulted in appropriate risk stratification of symptomatic patients with significant obesity. A normal SE portends an excellent outcome over the short-intermediate term in this high-risk patient population.

Role of simultaneous carotid ultrasound in patients undergoing stress echocardiography for assessment of chest pain with no previous history of coronary artery disease.

BACKGROUND: We prospectively explored prevalence of carotid disease (CD), its independent association with coronary artery disease (CAD) and outcome as well as potential impact on management, in patients undergoing stress echocardiography (SE) for new onset chest pain without known CAD. METHODS: Accordingly, 591 consecutive patients referred for SE underwent carotid ultrasound. Carotid disease was defined as carotid intima-media thickness (C-IMT) >75th percentile for age and sex and/or presence of plaque. RESULTS: Myocardial ischemia was demonstrated in only a minority (11%), but there was a high prevalence of CD (70%). Incidence of CD was similar in patients with and without ischemia (76% versus 69%, P = .26). Carotid data led to reclassification of Framingham risk score categories in 65% of patients as well as more than a third of negative SE patients potentially benefitting from primary prevention therapy. Of the 83 patients undergoing coronary arteriography, 59 (71%) demonstrated coronary atherosclerosis (any atheroma) and 33 (40%) CAD. Positive predictive value of SE for CAD was 56%, but presence of carotid plaque improved it to 70%. Although both CD and plaque showed association with CAD and revascularization, after adjustment for conventional risk factors, only carotid plaque maintained significant association (P = .024 and P = .023, respectively). CONCLUSIONS: There is significantly higher prevalence of CD compared with myocardial ischemia in patients undergoing SE and carotid ultrasound for suspected CAD. This can lead to significant Framingham risk score reclassification with important primary prevention implications. Carotid plaque is superior to clinical assessment for the prediction of CAD and improves positive predictive value of SE for CAD in these patients.