Utilization of stress echocardiography in patients with multivessel coronary artery disease.

OBJECTIVE: The purpose of this study was to evaluate the role of stress echocardiography in the risk stratification and prognosis of patients with multivessel coronary artery disease (CAD). BACKGROUND: Stress echocardiography is an established technique for diagnosis, risk stratification, and prognosis of patients with known or suspected CAD. METHODS: We evaluated 409 patients (65 ±â€Š10 years; 63% men) referred for stress echocardiography (45% treadmill, 55% dobutamine), who underwent stress echocardiography and coronary angiography within 3 months. All patients had multivessel CAD as defined by coronary stenosis (≥50% left main or ≥70% in two or more major epicardial vessels or branches). The left ventricle was divided into 16 segments and was scored on a five-point scale of wall motion. Patients with abnormal results on stress echocardiography were defined as those with stress-induced ischemia (increase in wall motion score of ≥1 grade). RESULTS: Follow-up (3.1 ±â€Š1.3 years) for nonfatal myocardial infarction (n = 35) and cardiac death (n = 25) was obtained. In patients with multivessel CAD, stress echocardiography effectively risk-stratified normal (no ischemia, n = 83) vs. abnormal (ischemia, n = 326) groups for cardiac events (event rate 1.9 vs. 5.4%/year; P < 0.01). Multivariable Cox proportional-hazards regression model identified stress-induced ischemia (hazard ratio 5.5, 95% confidence interval 1.9-15.9, P = 0.002) as the most significant predictor of adverse cardiac events. A stepwise Cox proportional-hazards model demonstrated significant incremental prognostic value of stress echocardiography over clinical variables, stress electrocardiography and resting left ventricular function (P < 0.0001), with the highest global chi-square value. CONCLUSIONS: In patients with angiographically significant multivessel CAD, despite normal-stress echocardiography, there was an intermediate cardiac event rate (1.9%/year); abnormal-stress echocardiography identified a high-risk group (5.4%/year); and stress echocardiography provided incremental prognostic value for risk stratification and prediction of cardiac events.

Prognostic Value of Stress Echocardiography in Patients With Low-Intermediate or High Short-Term (10 Years) Versus Low (<39%) or High (≥39%) Lifetime Predicted Risk of Cardiovascular Disease According to the American College of Cardiology/American Heart Association 2013 Cardiovascular Risk Calculator.

This study evaluates the prognostic value of stress echocardiography (Secho) in short-term (10 years) and lifetime atherosclerotic cardiovascular disease risk-defined groups according to the American College of Cardiology/American Heart Association 2013 cardiovascular risk calculator. The ideal risk assessment and management of patients with low-to-intermediate or high short-term versus low (<39%) or high (≥39%) lifetime CV risk is unclear. The purpose of this study was to evaluate the prognostic value of Secho in short-term and lifetime CV risk-defined groups. We evaluated 4,566 patients (60 ± 13 years; 46% men) who underwent Secho (41% treadmill and 59% dobutamine) with low-intermediate short-term (<20%) risk divided into low (<39%, n = 368) or high (≥39%, n = 661) lifetime CV risk and third group with high short-term risk (≥20%, n = 3,537). Follow-up (3.2 ± 1.5 years) for nonfatal myocardial infarction (n = 102) and cardiac death (n = 140) were obtained. By univariate analysis, age (p <0.001) and ≥3 new ischemic wall motion abnormalities (WMAs, p <0.001) were significant predictors of cardiac events. Cumulative survival in patients was significantly worse in patients with ≥3 WMA versus <3 WMA in low-intermediate short-term and low (3.3% vs 0.3% per year, p <0.001) or high (2.0% vs 0% per year, p <0.001) lifetime risk and also in those with high short-term CV risk group (3.5% vs 1.0% per year, p <0.001). Multivariate Cox proportional hazards analysis identified ≥3 new ischemic WMAs as the strongest predictor of cardiac events (hazard ratio 3.0, 95% confidence interval 2.3 to 3.9, p <0.001). In conclusion, Secho results (absence or presence of ≥3 new ischemic segments) can further refine risk assessment in patients with low-intermediate or high short-term versus low or high lifetime cardiovascular risk. Event rate with normal Secho is low (≤1% per year) but higher in patients with high short-term CV risk by the American College of Cardiology/American Heart Association 2013 cardiovascular risk calculator.

Prognostic value of treadmill stress echocardiography at extremes of exercise performance: submaximal <85% maximum predicted heart rate versus high exercise capacity ≥ 10 metabolic equivalents.

BACKGROUND: Submaximal stress testing or achieving <85% maximum predicted heart rate (MPHR) may lead to nondiagnostic results and indeterminate outcomes. High exercise capacity (≥ 10 metabolic equivalents, METS) is a predictor of favorable prognosis. The purpose of this study was to evaluate the prognostic value of submaximal or high exercise capacity stress echocardiography. METHODS: We evaluated 1781 patients (55 ± 13 years; 59% male) undergoing treadmill stress echocardiography divided into 811 patients with submaximal (<85% MPHR) and 970 patients with high exercise capacity (≥ 10 METS). Resting left ventricular ejection fraction and regional wall motion were assessed. The left ventricle was divided into 16 segments and scored on 5-point scale of wall motion. Abnormal stress echocardiography was defined as stress-induced ischemia (wall-motion score of ≥ 1 grade). Follow-up (3.3 ± 1.5 years) for nonfatal myocardial infarction (MI) (n = 40) and cardiac death (n = 52) were obtained. RESULTS: By univariate analysis, echocardiographic variables of ejection fraction, peak wall-motion score index (WMSI) and number of new ischemic wall-motion abnormalities were significant predictors of cardiac events. Cumulative survival was significantly worse in patients with abnormal (ischemic) versus normal (nonischemic) stress echocardiography in submaximal (4.4%/year vs. 1.3%/year, P < 0.0001) and high exercise capacity (1.5%/year vs. 0.2%/year, P < 0.0001) studies. Multivariate Cox proportional hazards analysis identified number of new ischemic wall-motion abnormalities as the strongest predictor of cardiac events (P < 0.05) in both groups. CONCLUSIONS: Despite normal stress echocardiography, the inability to achieve 85% MPHR conferred a higher, intermediate cardiac event rate of 2.9%/year. The ability to achieve 9 minutes (≥ 10 metabolic equivalents, METS) conferred an overall low cardiac event rate of 0.4%/year. However, the absence or presence of ischemia by stress echocardiography was able to further risk stratify patients with either submaximal or high exercise capacity studies.

Effect of body mass index on outcome in patients with suspected coronary artery disease referred for stress echocardiography.

In patients with hypertension, heart failure, or coronary artery disease (CAD), obese patients have been shown to have a lower cardiac event rate compared with normal weight counterparts. This phenomenon has been termed the "obesity paradox." We sought to determine whether the obesity paradox exists in a cohort of patients referred for stress echocardiography. We evaluated 4,103 patients with suspected CAD (58 ± 13 years; 42% men) undergoing stress echocardiography (52% exercise and 47% dobutamine). Patients were divided into 3 groups on the basis of body mass index (BMI): 18.5 to 24.9, 25 to 29.9, and >30 kg/m(2). During the follow-up of 8.2 ± 3.6 years, there were 683 deaths (17%). Myocardial ischemia was present in 21% of the population. Myocardial ischemia was more prevalent in patients with a BMI of 18.5 to 24.9 kg/m(2) (26%) than those with a BMI of 25 to 29.9 kg/m(2) (21%) and >30 kg/m(2) (18%). Patients with a BMI of >30 kg/m(2) had the lowest death rate (1.2%/year) compared with those with a BMI of 25 to 29.9 kg/m(2) (1.75%/year) and 18.5 to 24.9 kg/m(2) (2.9%/year; p <0.001). After adjusting for significant clinical variables including exercise capacity, patients with higher BMI (>30 kg/m(2) and 25 to 29.9 kg/m(2)) had less risk of mortality compared with those with a BMI of 18.5 to 24.9 kg/m(2) (hazard ratio 0.58, 95% confidence interval 0.47 to 0.72, p <0.0001 and hazard ratio 0.69, 95% confidence interval 0.57 to 0.82, p <0.0001, respectively). In conclusion, higher survival rate in patients with higher BMI as previously described in patients with hypertension, heart failure, and CAD extends to patients with suspected CAD referred for stress echocardiography, independent of exercise capacity.

Prognostic value of stress echocardiogram in patients with angiographically significant coronary artery disease.

The purpose of this study was to evaluate the prognostic value of stress echocardiography in patients with angiographically significant coronary artery disease (CAD). Two hundred sixty patients (mean age 63 ± 10 years, 58% men) who underwent stress echocardiography (41% treadmill, 59% dobutamine) and coronary angiography within 3 months and without intervening coronary revascularization were evaluated. All patients had significant CAD as defined by coronary stenosis ≥70% in major epicardial vessels or branches (45% had single-vessel disease, and 55% had multivessel disease). The left ventricle was divided into 16 segments and scored on a 5-point scale of wall motion. Patients with abnormal results on stress echocardiography were defined as those with stress-induced ischemia (increase in wall motion score of ≥1 grade). Follow-up (3.1 ± 1.2 years) for nonfatal myocardial infarction (n = 23) and cardiac death (n = 6) was obtained. In patients with angiographically significant CAD, stress echocardiography effectively risk stratified normal (no ischemia, n = 91) in contrast to abnormal (ischemia, n = 169) groups for cardiac events (event rate 1.0%/year vs 4.9%/year, p = 0.01). Multivariate logistic regression analysis identified multivessel CAD (hazard ratio 2.53, 95% confidence interval 1.16 to 5.51, p = 0.02) and number of segments in which ischemia was present (hazard ratio 4.31, 95% confidence interval 1.29 to 14.38, p = 0.01) as predictors of cardiac events. A Cox proportional-hazards model for cardiac events showed small, significant incremental value of stress echocardiography over coronary angiography (p = 0.02) and the highest global chi-square value for both (p = 0.004). In conclusion, in patients with angiographically significant CAD, (1) normal results on stress echocardiography conferred a benign prognosis (event rate 1.0%/year), and (2) stress echocardiographic results (no ischemia vs ischemia) added incremental prognostic value to coronary angiographic results, and (3) stress echocardiography and coronary angiography together provided additive prognostic value, with the highest global chi-square value.

Standing and exercise Doppler echocardiography in obstructive hypertrophic cardiomyopathy: the range of gradients with upright activity.

BACKGROUND: The ideal provocative maneuver in patients with hypertrophic cardiomyopathy (HCM) is a subject of ongoing investigation. Standing is a fundamental activity of daily life. This study examined acquisition of standing, Valsalva, and post-exercise left ventricular outflow tract gradients in HCM. METHODS: Rest supine, standing, and post-Valsalva gradients were measured in 98 consecutive patients with HCM who were referred for outpatient echocardiography. In 53 (54%) of the 98 patients, symptom-limited treadmill exercise was also performed, with gradients measured immediately after in the supine position. RESULTS: Fifty-six (57%) of the 98 patients had resting gradient<30 mm Hg and would thus be characterized as nonobstructive at rest. In the 98 patients, median gradients were 25 mm Hg at rest (range 0-205 mm Hg), increasing to 44 mm Hg after standing (range 0-309 mm Hg), an increase of 76%, and were again higher after Valsalva, 64 mm Hg (range 0-256 mm Hg) (P<.001). In the 53 patients who had gradient assessed after exercise, they were higher still, 100 mm Hg (range 0-256 mm Hg) (P<.001). In 29 patients (30%), standing provoked a higher gradient than Valsalva. CONCLUSION: Although standing increased gradients by 76%, it is not as potent a provocative maneuver as Valsalva or treadmill exercise. Nevertheless, standing is recommended as a physiologic provocative maneuver. In some patients standing may guide therapy; in others, the standing and exercise gradient provide a correct appreciation of the range of physiologically experienced gradients during daily upright activity.

Prognostic implications of stress echocardiography and impact on patient outcomes: an effective gatekeeper for coronary angiography and revascularization.

BACKGROUND: Stress echocardiography is an established technique for diagnosis, risk stratification, and prognosis in patients with known or suspected coronary artery disease. The ability of stress echocardiography to predict clinical outcomes, such as coronary angiography and revascularization, has not been reported previously. The purpose of this study was to evaluate the clinical outcomes of coronary angiography, revascularization, and cardiac events in patients undergoing stress echocardiography. METHODS: A total of 3121 patients (mean age, 60 + or - 13 years; 48% men) undergoing stress echocardiography (41% treadmill, 59% dobutamine) were assessed. Follow-up (mean, 2.8 + or - 1.1 years) for subsequent coronary angiography, revascularization (percutaneous coronary intervention [PCI] or coronary artery bypass grafting [CABG]), and confirmed hard events (nonfatal myocardial infarction or cardiac death) was obtained. RESULTS: Stress echocardiographic results were normal (peak wall motion score index [pWMSI], 1.0) in 66% and abnormal (pWMSI > 1.0) in 34% of patients. The pWMSI effectively risk-stratified patients into low-risk (pWMSI, 1.0; 0.8% per year), intermediate-risk (pWMSI, 1.1-1.7; 2.6% per year), and high-risk (pWMSI >1.7; 5.5% per year) groups for future cardiac events (P < .0001). Early coronary angiography (30 days following stress echocardiography) was performed in only 35 patients (1.7%) with normal stress echocardiographic results and 267 patients (25.5%) with abnormal stress echocardiographic results (P < .0001). Late coronary revascularization (2 years following stress echocardiography) occurred in 80 patients (PCI, 2.8%; CABG, 1.1%) with pWMSI values of 1.0, 123 patients (PCI, 13.5%; CABG, 7.3%) with pWMSI values of 1.1 to 1.7, and 102 patients (PCI, 12.7%; CABG, 9.6%) with pWMSI values > 1.7. Multivariate logistic regression analysis identified pWMSI as a predictor of coronary angiography (relative risk, 2.04; 95% confidence interval, 1.67-2.5), revascularization (relative risk, 1.91; 95% confidence interval, 1.68-2.17), and cardiac events (relative risk, 2.45; 95% confidence interval, 2.09-2.88) (all P values < .0001). Patients with markedly abnormal stress echocardiographic results (pWMSI > 1.7) had a significantly higher cardiac event rate in those who did not undergo coronary revascularization (9.6% per year vs 2.9% per year, P < .05). CONCLUSIONS: Stress echocardiography is an effective gatekeeper for coronary angiography and revascularization. Stress echocardiographic results influence clinical decision making in higher risk patients with significantly increased referral to coronary angiography and revascularization. Patients with markedly abnormal stress echocardiographic results (pWMSI > 1.7) were most likely to benefit from coronary revascularization.

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.

Prediction of myocardial infarction versus cardiac death by stress echocardiography.

BACKGROUND: The echocardiography literature to date has considered cardiac death and myocardial infarction (MI) as a combined end point. The purposes of the present study were to evaluate the differential prognosis of nonfatal MI versus cardiac death in patients undergoing stress echocardiography and to effectively risk stratify patients using the appropriate combination of functional, ischemic, and infarction data. METHODS: The authors evaluated 3,259 patients (mean age, 59 +/- 13 years; 48% men) undergoing stress echocardiography. Follow-up (mean, 2.8 +/- 1.1 years) for confirmed nonfatal MI (n = 91) and cardiac death (n = 105) was obtained. RESULTS: Multivariate analysis showed that the strongest predictor of cardiac death was a low ejection fraction (chi(2) = 37.3, P < .0001), and the strongest predictor of nonfatal MI was the extent of ischemia (chi(2) = 12.3, P < .0001). The relationship between ejection fraction and cardiac death rate was an exponential curve (y = 16.91e(-0.50x); r = -0.99, P < .0001). Among patients with ejection fractions > 30% (the low-risk to intermediate-risk groups), peak wall motion score index (WMSI) was able to further risk stratify patients into a very low risk group (peak WMSI = 1.0; cardiac death rate, 0.26% per year) and a higher risk group (peak WMSI > 1.7; cardiac death rate, 2.56% per year). However, patients with ejection fractions < 30% had high cardiac death risk regardless of peak WMSI category. CONCLUSIONS: In patients referred for stress echocardiography, the integration of functional information (on the basis of ejection fraction) and ischemic and infarction data (on the basis of WMSI) effectively risk stratifies patients for the outcome-specific end points of cardiac death and nonfatal MI.

Role of right ventricular wall motion abnormalities in risk stratification and prognosis of patients referred for stress echocardiography.

OBJECTIVES: The purpose of this study was to evaluate the prognostic value of assessing right ventricular (RV) wall motion abnormalities during stress echocardiography (SE). BACKGROUND: The results of SE are usually interpreted based on wall motion abnormalities of the left ventricle (LV). There is increasing recognition of the prognostic importance of RV. However, RV is still a "forgotten" chamber during routine SE. METHODS: We evaluated 2,703 patients referred for SE. The LV was evaluated on a 16-segment model 5-point scale and the RV was evaluated on a 3-segment model 5-point scale for wall motion abnormalities. An abnormal RV or LV was defined as one with new (ischemic) or fixed (infarction) wall motion abnormalities. Follow-up (2.7 +/- 1.0 years) for confirmed myocardial infarction and cardiac death (n = 122) were obtained. RESULTS: An abnormal RV was seen in 112 patients (4%). In the presence of an abnormal LV, patients with abnormal RV had a worse prognosis than those with normal RV. Abnormal RV was a significant predictor of events (adjusted hazard ratio 2.69, 95% confidence interval 1.22 to 5.92; p = 0.014) independent of LV ischemia and ejection fraction. A forward conditional Cox model showed that peak RV wall motion score index provided incremental prognostic value over rest and conventional SE variables (global chi-square increased from 141.4 to 161.8 to 197.0; p < 0.0001 and p = 0.006, respectively). CONCLUSIONS: In patients referred for SE, RV wall motion analysis provides prognostic value independent of LV ischemia and ejection fraction and provides incremental value over rest and conventional SE variables. Right ventricular wall motion analysis should be routinely performed in patients referred for SE for effective risk stratification.

Role of left atrial size in risk stratification and prognosis of patients undergoing stress echocardiography.

OBJECTIVES: The purpose of this study was to evaluate the role of diastolic dysfunction as measured by left atrial (LA) size in patients undergoing stress echocardiography (SE). BACKGROUND: Left atrial size is a surrogate marker of diastolic function. However, its prognostic value in patients referred for SE is not well defined. METHODS: We evaluated 2,705 patients (60 +/- 13 years, 47% men) undergoing SE (56% dobutamine). Patients with significant mitral valve disease (mitral stenosis or > or = moderate mitral regurgitation) were excluded. Enlarged LA was defined as a LA size indexed to body surface area > or =2.4 cm/m2. Follow-up (mean 2.7 +/- 1.0 years) for nonfatal myocardial infarction or cardiac death (n = 122) was obtained. RESULTS: A dilated LA was able to further risk-stratify both the normal and abnormal SE groups. In the presence of a dilated LA, an abnormal SE portends a worse prognosis compared with patients with normal LA size. Cox proportional modeling showed that a dilated LA added incremental value over traditional risk factors, stress electrocardiographic, rest echocardiographic, and SE variables for the prediction of hard events (global chi-square increased from 90.4 to 113.1 to 176.1 to 184.4 to 190.5; p < 0.05 all groups). Left atrial size was a significant predictor of events independent of left ventricular systolic dysfunction and ischemia (relative risk = 1.84, 95% confidence interval 1.19 to 2.85; p = 0.006). CONCLUSIONS: In patients referred for stress echocardiography, LA size provides independent and incremental value over standard risk factors including left ventricular systolic dysfunction and ischemia. Left atrial size is a powerful prognosticator and should be routinely used in the prognostic interpretation of stress echocardiography.

Risk stratification and prognosis in octogenarians undergoing stress echocardiographic study.

BACKGROUND: The prognostic value of stress echocardiography (SE) for the diagnosis and risk stratification of coronary artery disease in octogenarians is not well defined. METHODS: Follow-up of 5 years (mean 2.9 +/- 1.0 years) for confirmed nonfatal myocardial infarction (n = 17) and cardiac death (n = 37) was obtained in 335 patients, age > or =80 years (mean age 84 +/- 3 years, 44% male), undergoing SE (33% treadmill, 67% dobutamine). Left ventricular (LV) regional wall motion was assessed by a consensus of two echocardiographers and scored as per standard five-point scale, 16-segment model of wall motion analysis. Ischemic LV wall segment was defined as deterioration in the thickening and excursion during stress (increase in wall-motion score index (WMSI) > or =1). RESULTS: By univariate analysis, inducible ischemia (chi-square = 38.4, P < 0.001), left ventricular ejection fraction (chi-square = 41.2, P < 0.001), a history of previous myocardial infarction (chi-square = 22.3, P < 0.01), hypertension (chi-square = 33, P < 0.01), and age (chi-square = 27.7, P < 0.01) were significant predictors of future cardiac events. WMSI, an index of inducible ischemia, provided incremental prognostic information when forced into a multivariable model where clinical and rest echocardiography variables were entered first. WMSI effectively stratified octogenarians into low- and high-risk groups (annualized event rates of 1.2 versus 5.8%/year, P < 0.001). CONCLUSIONS: Stress echocardiography yields incremental prognostic information in octogenarians and effectively stratifies them into low- and high-risk groups. Precise therapeutic decision making in very elderly patients should incorporate combined clinical and stress echocardiography data.

Usefulness of stress echocardiography for risk stratification and prognosis of patients with left ventricular hypertrophy.

The purpose of this study was to evaluate the role of stress echocardiography in the risk stratification and prognosis of patients with left ventricular (LV) hypertrophy. One thousand two patients (mean age 62 +/- 13 years, 35% men) with LV hypertrophy (defined by LV mass index >115 g/m(2) for men and >95 g/m(2) for women) were evaluated. LV mass was calculated using the linear dimension method, as recommended by the American Society of Echocardiography. The calculation of relative wall thickness was performed using the formula (2 x posterior wall thickness)/LV internal diameter. Concentric and eccentric LV hypertrophy were defined as relative wall thicknesses > or =0.42 and <0.42 cm, respectively. Follow-up (2.6 +/- 1.1 years) for confirmed myocardial infarction and cardiac death (n = 71) was obtained. Four hundred seventy-three patients (47%) had concentric hypertrophy, and 529 patients (53%) had eccentric hypertrophy. In patients with either concentric or eccentric LV hypertrophy, stress echocardiography was able to effectively risk-stratify normal versus abnormal subgroups (event rate 1.1% vs 4.9% per year, p <0.0001), whereas stress electrocardiography was unable to do so. In the cohort with normal stress echocardiographic results, patients with concentric LV hypertrophy had an event rate 5 times higher than those with eccentric LV hypertrophy (event rate 1.7% vs 0.3% per year, p = 0.007). In conclusion, stress echocardiography effectively risk-stratifies patients with LV hypertrophy compared with stress electrocardiography. Normal stress echocardiographic results in patients with concentric LV hypertrophy indicate a worse prognosis than in patients with eccentric LV hypertrophy, probably reflecting decreased sensitivity in this cohort. However, abnormal stress echocardiographic results portend a worse prognosis in patients with either concentric or eccentric LV hypertrophy.

Transient ischemic left ventricular cavity dilation is a significant predictor of severe and extensive coronary artery disease and adverse outcome in patients undergoing stress echocardiography.

BACKGROUND: Transient ischemic dilation (TID) of the left ventricle on stress-redistribution thallium-201 scintigraphy is a marker of severe and extensive coronary artery disease (CAD), and associated with an adverse outcome. The significance of transient ischemic dilation during stress echocardiography is not well defined. METHODS: We assessed 155 patients undergoing stress echocardiography (61% treadmill exercise, 39% dobutamine) with confirmed follow-up (mean 2.8 +/- 1.1 years) for hard events (myocardial infarction, n = 14, and cardiac death, n = 9). RESULTS: Normal limits for TID ratio were developed using data from 39 patients with a low likelihood (<5%) of CAD and normal stress echocardiography study findings. The criteria for abnormality was developed based on data from 116 patients who underwent coronary angiography after and within 3 months of an abnormal ischemic stress echocardiography study result. For normal limits, receiver operating characteristic curve analysis showed that abnormal TID ratio values corresponded to left ventricular volume ratios greater than 1.17 (mean +/- 2SD). TID assessment using these criteria for abnormality showed high sensitivity (100%) and moderate specificity (54%) for detection of severe and extensive angiographic CAD. Patients with TID had a greater extent and severity of stress induced wall-motion abnormalities, higher peak wall-motion score index, and worse prognosis than patients without TID. CONCLUSIONS: TID during stress echocardiography is a sensitive marker of severe and extensive angiographic CAD and is associated with a high risk of cardiac events (19.7%/y event rate).

Risk stratification using stress echocardiography: incremental prognostic value over historic, clinical, and stress electrocardiographic variables across a wide spectrum of bayesian pretest probabilities for coronary artery disease.

OBJECTIVES: We sought to evaluate the risk stratification ability and incremental prognostic value of stress echocardiography over historic, clinical, and stress electrocardiographic (ECG) variables, over a wide spectrum of bayesian pretest probabilities of coronary artery disease (CAD). BACKGROUND: Stress echocardiography is an established technique for the diagnosis of CAD. However, data on incremental prognostic value of stress echocardiography over historic, clinical, and stress ECG variables in patients with known or suggested CAD is limited. METHODS: We evaluated 3259 patients (60 +/- 13 years, 48% men) undergoing stress echocardiography. Patients were grouped into low (<15%), intermediate (15-85%), and high (>85%) pretest CAD likelihood subgroups using standard software. The historical, clinical, stress ECG, and stress echocardiographic variables were recorded for the entire cohort. Follow-up (2.7 +/- 1.1 years) for confirmed myocardial infarction (n = 66) and cardiac death (n = 105) was obtained. RESULTS: For the entire cohort, an ischemic stress echocardiography study confers a 5.0 times higher cardiac event rate than the normal stress echocardiography group (4.0% vs 0.8%/y, P < .0001). Furthermore, Cox proportional hazard regression model showed incremental prognostic value of stress echocardiography variables over historic, clinical, and stress ECG variables across all pretest probability subgroups (global chi2 increased from 5.1 to 8.5 to 20.1 in the low pretest group, P = .44 and P = .01; from 20.9 to 28.2 to 116 in the intermediate pretest group, P = .47 and P < .0001; and from 17.5 to 36.6 to 61.4 in the high pretest group, P < .0001 for both groups). CONCLUSIONS: A normal stress echocardiography portends a benign prognosis (<1% event rate/y) in all pretest probability subgroups and even in patients with high pretest probability and yields incremental prognostic value over historic, clinical, and stress ECG variables across all pretest probability subgroups. The best incremental value is, however, in the intermediate pretest probability subgroup.

Role of angiographic coronary artery collaterals in transient ischemic left ventricular cavity dilatation during stress echocardiography.

BACKGROUND: The role of coronary artery collaterals in transient ischemic left ventricular (LV) dilatation (TID) during stress echocardiography is not well defined. HYPOTHESIS: Transient ischemic LV dilatation is a marker for extensive and severe coronary artery disease and represents patients without good collaterals. METHODS: We evaluated 212 consecutive patients (57 +/- 16 years, 70% male) who had coronary angiography and stress echocardiography within a 3-month period. This cohort of patients was divided into three groups based on type of collaterals: Group A: no collaterals; Group B: collaterals supplied by vessels without flow-limiting stenosis (good collaterals); Group C: collaterals supplied by vessels with flow-limiting stenosis (bad/jeopardized collaterals). In all patients, angiographic jeopardy score (AJS), ejection fraction (EF), and wall motion score index (WMSI) at rest and during stress were evaluated. Transient ischemic LV dilatation was defined as transient increase in the end-systolic dimensions from rest to peak stress. RESULTS: Transient ischemic LV dilatation was present in 42 (20%) patients. Patients with TID had a lower EF, higher AJS, greater number of ischemic segments, and higher peak WMSI. Patients with TID in Group A (no collaterals) and Group C (jeopardized collaterals) had a greater percentage of multivessel disease than those in Group B (good collaterals). Presence of Group A or Group C collaterals was a predictor of TID even after controlling for multivessel disease, rest and peak WMSI, and left anterior descending artery disease. CONCLUSIONS: Transient ischemic LV dilatation on stress echocardiography is a marker for extensive and severe coronary artery disease and represents patients with angiographically absent collaterals or those with jeopardized coronary collaterals.

Incremental prognostic value of stress echocardiography over clinical and stress electrocardiographic variables in patients with prior myocardial infarction: "warranty time" of a normal stress echocardiogram.

BACKGROUND: Patients with prior myocardial infarction (MI) are at increased risk of subsequent cardiac events (MI or cardiac death). The incremental prognostic value and warranty time of a normal stress echocardiogram in this high-risk population is not well defined. METHODS: We evaluated 251 consecutive patients (62 +/- 11 years; 64% males) with remote history of MI (>6 weeks) undergoing stress echocardiography (83% dobutamine). Ischemia was defined as a new reversible wall motion abnormality and/or biphasic response. Follow-up for up to 4 years (mean 2.9 +/- 1.0 years) for confirmed MI (n = 7) and cardiac death (n = 15) were obtained. RESULTS: Stress echocardiography effectively risk stratified patients into normal versus abnormal subgroups (Event rate 0.8% per year vs 4.2% per year; P = 0.01; RR = 5.6, 95% CI = 1.3-24.7). In patients with a normal stress echocardiogram, the event rate at the end of 6, 12, and 18 months were <1% per year. After 18 months the event rate in patients with a normal stress echocardiogram increased greatly (>1% per year). Stress echocardiography yields incremental prognostic value over clinical and stress electrocardiographic variables (Global chi-square increased from 12.4 to 25 to 31.1, P < 0.0001 both groups). CONCLUSIONS: Stress echocardiography yields appropriate risk stratification and prognosis and provides incremental prognostic value over clinical and stress electrocardiographic variables even in patients with prior MI. A normal stress echocardiogram portends a benign prognosis (<1% event rate/year) for up to 18 months.