The prognostic value of dobutamine stress echocardiography amongst British Indian Asian and Afro-Caribbean patients: a comparison with European white patients

Abstract

BackgroundThe incidence of cardiovascular disease is considerably disparate among different racial and ethnic populations. While dobutamine stress echocardiography (DSE) has been shown to be useful in Caucasian patients, its role among ethnic minority groups remains unclear. This study aimed to investigate the prognostic importance of DSE in three ethnic groups in the UK.MethodsDSE was performed on 6231 consecutive patients. After exclusions, 5329 patients formed the study (2676 [50.2 %] Indian Asian, 2219 [41.6 %] European white and 434 [8.1 %] Afro-Caribbean). Study outcome measures were non-fatal cardiac events (NFCE) and all-cause mortality.ResultsThere were 849 (15.9 %) NFCE and 1365 (25.6 %) deaths over a median follow-up period of 4.6 years. In total 1174 (22 %) patients had inducible myocardial ischaemia during DSE, 859 (16.1 %) had fixed wall motion abnormalities and 3645 (68.4 %) patients had a normal study. Ethnicity did not predict events. Among the three ethnic groups, ischaemia on DSE was associated with 2 to 2.5 times the risk of non-fatal cardiac events and 1.2 to 1.4 times the risk of all-cause mortality. Peak wall motion score index was the strongest independent predictor of non-fatal cardiac events and all-cause mortality in all groups. The C statistic for the prediction of NFCE and all-cause mortality were significantly higher when DSE parameters were added to the standard risk factors for all ethnic groups.ConclusionsDSE is a strong predictor of NFCE and all-cause mortality and provides predictive information beyond that provided by standard risk factors in three major racial and ethnic groups. No major differences among racial and ethnic groups in the predictive value of DSE was detected.Electronic supplementary materialThe online version of this article (doi:10.1186/s12947-015-0028-1) contains supplementary material, which is available to authorized users.

Cardiac Risk Factors for Patients under DSE

“…A detailed description of the data set, collection method, patient population, and the DSE is given in [8]. Effects of dobutamine stress echocardiography have been described in many articles [9][10][11][12]. The variables/ factors of this study are Basal heart rate (bpm) (coded as bhr), Basal blood pressure (mmHg) (coded as basebp), Basal double product (DP) (bhr * basebp) (bpm * mmHg) (coded as basedp), Peak heart rate (bpm) (coded as pkhr), Systolic blood pressure (mmHg) (coded as sbp), DP pkhr * sbp (bpm * mmHg) (coded as dp), Dobutamine dose (DD) given (coded as dose), Maximum heart rate (bpm) (coded as maxhr), Percent maximum predicted heart rate (coded as pctMphr), Maximum blood pressure (mmHg) (coded as mbp), DP on max DD (bpm * mmHg) (coded as dpmaxdo), DD at max double product (mg) (coded as dobdose), Age (years) (coded as age), Gender (male=0, female=1) (coded as gender), Baseline cardiac ejection fraction (coded as baseEF), Ejection fraction on dobutamine (coded as dobEF), Chest pain (yes (y)=0, no (n)=1) (coded as chestpain), Resting wall motion abnormality on echocardiogram (ECDG) (y=0, n=1) (coded as restwma), Positive stress ECDG (y=0, n=1) (coded as posSE), New myocardial infraction (MI) (y=0, n=1) (coded as newMI), Recent angioplasty (y=0, n=1) (coded as newPTCA), Recent bypass surgery (y=0, n=1) (coded as newCABG), death (y=0, n=1) (coded as death), History of hypertension (y=0, n=1) (coded as hxofHT), History of diabetes (y=0, n=1) (coded as hxofDM), History of smoking (non-smoker=0, moderate=1, heavy=2) (coded as hxofCig), History of MI (y=0, n=1) (coded as hxofMI), History of angioplasty (y=0, n=1) (coded as hxofPTCA), History of coronary artery bypass surgery (y=0, n=1) (coded as hxofCABG), Death, newMI, newPTCA or newCABG (death=0, no=1) (coded as any event), Baseline electrocardiogram diagnosis (normal=0, equivocal=1, MI=2) (coded as ecg).…”