Valve disease in cardiac amyloidosis: an echocardiographic score.

Cardiac amyloidosis (CA) may affect all cardiac structures, including the valves. From 423 patients undergoing a diagnostic workup for CA we selected 2 samples of 20 patients with amyloid transthyretin (ATTR-) or light-chain (AL-) CA, and age- and sex-matched controls. We chose 31 echocardiographic items related to the mitral, aortic and tricuspid valves, giving a value of 1 to each abnormal item. Patients with ATTR-CA displayed more often a shortened/hidden and restricted posterior mitral valve leaflet (PMVL), thickened mitral chordae tendineae and aortic stenosis than those with AL-CA, and less frequent PMVL calcification than matched controls. Score values were 15.8 (13.6-17.4) in ATTR-CA, 11.0 (9.3-14.9) in AL-CA, 12.8 (11.1-14.4) in ATTR-CA controls, and 11.0 (9.1-13.0) in AL-CA controls (p = 0.004 for ATTR- vs. AL-CA, 0.009 for ATTR-CA vs. their controls, and 0.461 for AL-CA vs. controls). Area under the curve values to diagnose ATTR-CA were 0.782 in patients with ATTR-CA or matched controls, and 0.773 in patients with LV hypertrophy. Patients with ATTR-CA have a prominent impairment of mitral valve structure and function, and higher score values. The valve score may help identify patients with ATTR-CA among patients with CA or unexplained hypertrophy.

Life-threatening paradoxical thromboembolism in a patient with patent foramen ovale.

BACKGROUND: Venous thromboembolism represents the third most frequent acute cardiovascular syndrome worldwide. Its clinical manifestations are deep vein thrombosis and/or pulmonary embolism. Despite a considerable mortality, diagnosis is often missed.  CASE PRESENTATION: We report the management of a female patient with high-risk pulmonary thromboembolism treated initially with thromboaspiration, complicated by embolus jailing in a patent foramen ovale. In this situation, left cardiac chambers and systemic circulation were jeopardized by this floating embolus. CONCLUSIONS: High-risk pulmonary embolism requires reperfusion strategy but sometimes mechanical thromboaspiration may be not fully successful; transesophageal echocardiography led to a prompt diagnosis of this unexpected finding; in this very particular case, open surgery represented a bail-out procedure to avoid cerebral and systemic embolism.

Multi-chamber speckle tracking imaging and diagnostic value of left atrial strain in cardiac amyloidosis.

AIMS: Cardiac amyloidosis (CA) affects the four heart chambers, which can all be evaluated through speckle-tracking echocardiography (STE). METHODS AND RESULTS: We evaluated 423 consecutive patients screened for CA over 5 years at two referral centres. CA was diagnosed in 261 patients (62%) with either amyloid transthyretin (ATTR; n = 144, 34%) or amyloid light-chain (AL; n = 117, 28%) CA. Strain parameters of all chambers were altered in CA patients, particularly those with ATTR-CA. Nonetheless, only peak left atrial longitudinal strain (LA-PALS) displayed an independent association with the diagnosis of CA or ATTR-CA beyond standard echocardiographic variables and cardiac biomarkers (Model 1), or with the diagnosis of ATTR-CA beyond the validated IWT score in patients with unexplained left ventricular (LV) hypertrophy. Patients with the most severe impairment of LA strain were those most likely to have CA or ATTR-CA. Specifically, LA-PALS and/or LA-peak atrial contraction strain (PACS) in the first quartile (i.e. LA-PALS <6.65% and/or LA-PACS <3.62%) had a 3.60-fold higher risk of CA, and a 3.68-fold higher risk of ATTR-CA beyond Model 1. Among patients with unexplained LV hypertrophy, those with LA-PALS or LA-PACS in the first quartile had an 8.76-fold higher risk for CA beyond Model 1, and a 2.04-fold higher risk of ATTR-CA beyond the IWT score. CONCLUSIONS: Among STE measures of the four chambers, PALS and PACS are the most informative ones to diagnose CA and ATTR-CA. Patients screened for CA and having LA-PALS and/or LA-PACS in the first quartile have a high likelihood of CA and ATTR-CA.

Prognostic value of reverse remodelling criteria in heart failure with reduced or mid-range ejection fraction.

AIMS: Reverse remodelling (RR) is the recovery from left ventricular (LV) dilatation and dysfunction. Many arbitrary criteria for RR have been proposed. We searched the criteria with the strongest prognostic yield for the hard endpoint of cardiovascular death. METHODS AND RESULTS: We performed a systematic literature search of diagnostic criteria for RR. We evaluated their prognostic significance in a cohort of 927 patients with LV ejection fraction (LVEF) < 50% undergoing two echocardiograms within 12 ± 2 months. These patients were followed for a median of 2.8 years (interquartile interval 1.3-4.9) after the second echocardiogram, recording 123 cardiovascular deaths. Two prognostic models were defined. Model 1 included age, LVEF, N-terminal pro-B-type natriuretic peptide, ischaemic aetiology, cardiac resynchronization therapy, estimated glomerular filtration rate, New York Heart Association, and LV end-systolic volume (LVESV) index, and Model 2 the validated Cardiac and Comorbid Conditions Heart Failure score. We identified 25 criteria for RR, the most used being LVESV reduction ≥15% (12 studies out of 42). In the whole cohort, two criteria proved particularly effective in risk reclassification over Model 1 and Model 2. These criteria were (i) LVEF increase >10 U and (ii) LVEF increase ≥1 category [severe (LVEF ≤ 30%), moderate (LVEF 31-40%), mild LV dysfunction (LVEF 41-55%), and normal LV function (LVEF ≥ 56%)]. The same two criteria yielded independent prognostic significance and improved risk reclassification even in patients with more severe systolic dysfunction, namely, those with LVEF < 40% or LVEF ≤ 35%. Furthermore, LVEF increase >10 U and LVEF increase ≥1 category displayed a greater prognostic value than LVESV reduction ≥15%, both in the whole cohort and in the subgroups with LVEF < 40% or LVEF ≤ 35%. For example, LVEF increase >10 U independently predicted cardiovascular death over Model 1 and LVESV reduction ≥15% (hazard ratio 0.40, 95% confidence interval 0.18-0.90, P = 0.026), while LVESV reduction ≥15% did not independently predict cardiovascular death (P = 0.112). CONCLUSIONS: Left ventricular ejection fraction increase >10 U and LVEF increase ≥1 category are stronger predictors of cardiovascular death than the most commonly used criterion for RR, namely, LVESV reduction ≥15%.

Myocardial stress perfusion scintigraphy for outcome prediction in patients with severe left ventricular systolic dysfunction.

Coronary angiography has been recommended in all patients with suspected chronic coronary syndrome and left ventricular ejection fraction (LVEF) ≤35%. The role of ischemia testing, for example, through stress-rest myocardial perfusion scintigraphy (MPS), for risk prediction is not well established. METHODS: We evaluated 1576 consecutive patients referred to MPS and stratified into 3 LV ejection fraction (LVEF) categories: ≤35%, 36-49%, and ≥ 50%. RESULTS: Patients with LVEF ≤35% were oldest, most often men, and with the highest likelihood of prior early (elective or urgent) coronary revascularization. They had also the highest values or summed stress score (SSS), summed rest score (SRS), and summed difference score (SDS), as well as the highest frequency of significant coronary artery disease, and a greater number of diseased vessels. FOLLOW-UP: In this subgroup, 32 cardiovascular death or non-fatal myocardial infarction (MI) (21%), 35 all-cause deaths (22%), and 37 cardiovascular deaths, non-fatal MI, or late revascularizations (27%) were recorded with the shortest survival among all LVEF classes. SRS, SSS, and SDS had very low area under the curve values for the prediction of the 3 endpoints, with very high cut-offs, respectively. SRS and SSS cut-offs predicted a worse outcome in Cox regression models including the number of diseased vessels and early revascularization. CONCLUSIONS: In patients with LVEF ≤35%, SRS and SSS are less predictive of outcome than in patients with better preserved systolic dysfunction, but their cut-offs retain independent prognostic significance from the number of vessels with significant stenoses and from early revascularization.

Appropriate choice of stress modality in patients undergoing myocardial perfusion scintigraphy with a cardiac camera equipped with solid-state detectors: the role of diabetes mellitus.

Aims: To evaluate the impact of diabetes mellitus (DM) on the accuracy of myocardial perfusion scintigraphy (MPS) in detecting coronary artery disease (CAD). Methods and results: Two hundred and sixteen patients with DM and 432 matched controls were submitted to MPS on a dedicated cardiac camera equipped with cadmium-zinc-telluride (CZT) detectors and coronary angiography. Exercise stress was performed in 442 (68%) patients, while the remainders underwent vasodilator stress. Exercise level was determined as the percentage of the predicted maximal workload that was attained (%Wattmax). The summed difference score was derived from CZT images. A coronary stenosis >70% was considered obstructive. The prevalence of obstructive CAD was 59.7% in patients with DM and 56.2% in controls (P = NS). The accuracy of MPS in detecting CAD was similar in patients with and without DM [area under the ROC curve (AUC) 0.77 vs. 0.78, P = NS]. An interaction between the accuracy of MPS and cardiac stress-protocol was revealed. In fact, in patients with DM exercise stress CZT had a lower accuracy than vasodilator-stress (AUC 0.70 vs. 0.89, P < 0.001), because of a lower specificity (45% vs. 69%), while in the control group the accuracy of MPS was similar regardless of the stress-protocol adopted. Patients with DM attained a significantly lower %Wattmax during exercise than controls (76 ± 27% vs. 82 ± 26%, P = 0.038), which resulted an independent predictor of reduced specificity (P = 0.026). Conclusion: The accuracy of CZT imaging in patients with DM is elevated, and it is quite comparable to the one obtained in patients without DM. However, a reduced specificity can be expected in the case of exercise stress CZT, because of an impaired exercise capacity.

LDL apheresis improves coronary flow reserve on the left anterior descending artery in patients with familial hypercholesterolemia and chronic ischemic heart disease.

BACKGROUND: LDL apheresis (LA) influences the microcirculation, endothelial function and cardiovascular homeostasis. The aim of our study was to analyze temporal variations of coronary flow reserve (CFR) on the left anterior descending artery, obtained during dipyridamole stress echocardiography (DSE), in patients with severe familial hypercholesterolemia on LA (LA group) or not (not LA group) and ischemic heart disease (IHD). METHODS: The LA group consisted in 10 patients (mean age 65 ± 7 years, male 70%) with Familial Hypercholesterolemia and chronic IHD on maximally tolerated lipid lowering therapy and chronic LA treatment (median 7 years, interquartile range 6-14 years). Hyperlipoproteinemia (a) was also present in 6/10 subjects. LA was performed biweekly by dextran-sulfate or heparin-induced LDL precipitation technique. IHD was diagnosed at a mean age of 44 ± 8 years. The control group was matched for age, sex and follow-up period. CFR was calculated as the ratio between blood diastolic velocity sampled at peak stress with dipyridamole and baseline diastolic velocity (normal value > 2.0). No relevant comorbidities were present. RESULTS: During a median follow-up of 27 months (interquartile range 23-50 months), a significant increase in CFR (from 1.86 ± 0.47 to 2.25 ± 0.35; p < 0.001) was observed in LA group. During this period, no patients modified their anti-ischemic therapy and no cardiovascular events were reported. In the control group, during the study time (24 months - interquartile range 14-57 months) no significant variation in CFR was observed (from 2.08 ± 0.39 to 1.92 ± 0.26; p 0.283). CONCLUSION: Myocardial blood perfusion, measured as CFR by dipyridamole stress echocardiography-is increased in patients with severe familial hypercholesterolemia chronically treated with LA. DSE might be a reliable tool to monitor the therapeutic effect of lipid lowering therapy.

Myocardial ischemia in the absence of obstructive coronary lesion: The role of post-stress diastolic dysfunction in detecting early coronary atherosclerosis.

BACKGROUND: The interactions between non-obstructive coronary atherosclerosis (<50% stenosis) and myocardial perfusion and functional parameters on myocardial perfusion imaging (MPI) have never been evaluated. METHODS AND RESULTS: One-hundred and ninety-five patients were submitted to stress-rest MPI and invasive coronary angiography. The presence of obstructive coronary lesions (>50% stenosis) was excluded. The summed stress score (SSS) was calculated in every patient. Moreover, the left ventricular (LV) ejection fraction (EF) and peak filling rate (PFR) were computed from gated MPI images as measures of systolic and diastolic functions. Sixty/195 patients (31%) showed the presence of non-obstructive atherosclerosis (>20% and <50% diameter reduction). Interestingly, they presented a higher SSS than those with normal coronary arteries (P < 0.001) despite a similar myocardial scar burden. If compared to patients with normal coronary arteries, those with non-obstructive atherosclerosis showed more abnormal post-stress PFR values (2.5 ± 0.9 vs 2.9 ± 0.8, P = 0.004), despite a similar EF. On multivariate analysis, the presence non-obstructive atherosclerosis was the only significant predictor (P = 0.026) of post-stress LV diastolic impairment, independently from perfusion parameters. CONCLUSIONS: In patients without anatomically significant coronary lesions, the development of post-stress LV diastolic dysfunction on MPI associates with the presence of non-obstructive atherosclerosis on coronary angiography.

Appropriate use criteria in clinical routine practice: implications in a nuclear cardiology lab.

The efforts for a broad application of the appropriate use criteria to reduce inappropriate nuclear stress testing have frequently been unsuccessful and the reported rates of inappropriateness have varied widely between studies. We sought to analyze the criteria of clinical appropriateness of a cohort of consecutive patients referred to our nuclear cardiology laboratory to perform stress myocardial perfusion imaging (MPI) and to assess the relationships between test appropriateness and the evaluation of ischaemia. A cohort of 251 consecutive patients, admitted to our Institute from January to March 2015, who underwent stress/rest MPI on a dedicated cardiac camera equipped with cadmium-zinc-telluride detectors, was selected. The level of clinical appropriateness of each MPI test was categorized in each patient according to the AUC criteria. According to the accepted criteria, the majority of the MPI stress-tests could be classified as clinically appropriate (218 of 251, 87 % of the tests), while only 16 (6 %) and 17 (7 %) resulted of uncertain appropriateness or clearly inappropriate, respectively. Of the 251 appropriate tests, 22 (10 %), 65 (30 %), and 131 (60 %) showed the presence of a mild (SDS < 4), moderate (4 ≥ SDS < 7), and severe (SDS ≥ 7) ischemic burden, respectively, while none of the inappropriate test showed moderate-to-severe ischaemia (P < 0.001 for comparisons). The rate of inappropriate MPI tests is considerably low in a high-volume laboratory. Appropriate and inappropriate studies identify patients at high and low probability of significant ischemia, respectively, providing insights on the effects of the level of appropriateness on stress-test results.

Influence of cardiac stress protocol on myocardial perfusion imaging accuracy: The role of exercise level on the evaluation of ischemic burden.

BACKGROUND: Some specifics of cardiac stress protocols, i.e., stressor used or exercise level achieved, may impact myocardial perfusion imaging (MPI) accuracy. METHODS: Four-hundred and seventy-five patients were submitted to MPI and coronary angiography. MPI was performed after exercise (303 patients) or dipyridamole stress (172 patients). A coronary stenosis ≥70% was considered significant. In case of exercise test, a peak heart rate (HR) <85% of the maximal age predicted was considered submaximal and categorized as follows: >75% and <85% ("Group 1"); <75% ("Group 2"). RESULTS: At coronary angiography, 312/475 (66%) patients showed significant stenosis. In the overall population, MPI showed a high accuracy in unmasking significant coronary stenosis, independently of the stress protocol adopted (AUC .76 for exercise vs .78 for vasodilator; P = NS). However, in case of an exercise stress test, a significant interaction between peak %HR and MPI diagnostic power was evident. While an elevated accuracy was still maintained in "Group 1" patients (AUC .79; P vs maximal exercise = NS), a significant drop was demonstrated in "Group 2" patients (AUC .66; P vs maximal exercise = .012, and P vs "Group 1" = .042). CONCLUSIONS: The accuracy of MPI is not influenced by the stress protocol adopted. Exercise MPI maintains an elevated accuracy as long as the %HR remains >75%.

Determinants of left ventricular mechanical dyssynchrony in patients submitted to myocardial perfusion imaging: A cardiac CZT study.

BACKGROUND: An interaction between coronary anatomy, myocardial perfusion, and left ventricular (LV) functional parameters in the development of mechanical LV dyssynchrony (LVD) has been suggested. This study examined the correlates of LVD in a large sample size of patients with known or suspected coronary artery disease (CAD) using cadmium-zinc-telluride camera. METHODS: Six-hundred and fifty-seven consecutive patients who underwent myocardial perfusion imaging (MPI) and coronary angiography were included. Coronary stenosis >70% was considered significant. LV perfusion and functional parameters were computed from MPI images. The presence of significant LVD was evaluated by phase standard deviation and histogram bandwidth. RESULTS: 415/657 (63%) patients had significant CAD. LVD was present in 247 (38%) patients and was associated with the presence of a higher CAD burden (P < .001), more impaired measures of LV perfusion (P < .001), contractile function (P < .001), and larger LV volumes (P < .001). By multivariate analysis, the LV end-systolic volume index (P < .001) and ischemic burden (P < .001) were the strongest predictors of LVD independent of CAD extent and LV systolic dysfunction. CONCLUSIONS: LVD is frequent in patients undergoing MPI for suspected or known CAD. Its presence is independent of CAD burden and LV systolic dysfunction, but is dependent on the presence of myocardial perfusion abnormalities and LV end-systolic volume.

Relationships between myocardial perfusion abnormalities and poststress left ventricular functional impairment on cadmium-zinc-telluride imaging.

PURPOSE: To evaluate the interplay between myocardial ischaemic burden and poststress left ventricular (LV) systolic and diastolic abnormalities in patients with suspected or known coronary artery disease (CAD). METHODS: A total of 471 patients underwent myocardial perfusion imaging by cadmium-zinc-telluride scintigraphy and coronary angiography. A fast imaging protocol was used with stress imaging performed 10 - 15 min after tracer injection. The summed difference score (SDS) and the percent stress-to-rest ratios for LV ejection fraction and peak filling rate (PFR), measures of stress-induced systolic and diastolic impairment, were computed from scintigraphic images. A SDS of >3 was considered abnormal and >7 a marker of moderate-to-severe ischaemia. RESULTS: Of the 471 patients, 321 (68%) showed significant CAD in one (27%), two (23%) or three (18%) vessels. The extent of CAD associated with gradual alterations in SDS (P < 0.001). Interestingly, while impairment in the percent stress-to-rest PFR ratio paralleled the increase in the extent of CAD (P < 0.001 for trend), the occurrence of significant stress-induced systolic dysfunction was limited to patients with multivessel disease (P < 0.001 vs. patients without CAD, and P = 0.002 vs. patients with single-vessel disease). Similarly, while a strict correlation between percent stress-to-rest PFR ratio and myocardial ischaemic burden was evident (P < 0.001), significant stress-induced LV systolic impairment was limited to patients with moderate-to-severe ischaemia (P < 0.001 vs. patients with no or mild ischaemia). CONCLUSION: Stress-induced LV diastolic impairment is associated with a less extensive ischaemic burden and CAD extent than poststress systolic dysfunction, which is limited to patients with multivessel CAD.

Diastolic dysfunction assessed by ultra-fast cadmium-zinc-telluride cardiac imaging: impact on the evaluation of ischaemia.

AIM: The aim of this study was to evaluate the possible impact of stress-induced left ventricular (LV) diastolic dysfunction at cadmium-zinc-telluride (CZT) imaging, on the detection of significant coronary artery disease (CAD). METHODS AND RESULTS: Four hundred and twenty-five consecutive patients underwent myocardial perfusion imaging at rest and after stress with a low-dose CZT protocol and the evaluation of coronary anatomy by invasive or computed coronary angiography. The summed difference score (SDS) was calculated in every patient. Left ventricular ejection fraction and peak filling rate (PFR) at baseline and after stress were derived from gated CZT images and the '% stress-to-rest' PFR difference, as an indicator of stress-induced diastolic dysfunction, determined. In the study population, the mean SDS was 5 ± 4, while mean stress PFR and rest PFR were 2.5 ± 0.8 end-diastolic volumes (EDV)/s and 2.5 ± 0.7 EDV/s, respectively. There was a strict correlation between the presence and extent of CAD and both myocardial SDS and '% stress-to-rest' PFR (P < 0.001 for both). Interestingly, while myocardial SDS and '% stress-to-rest' PFR were significantly correlated (P < 0.001), they resulted independent predictors of the presence of significant CAD (P < 0.001 and P < 0.032, respectively). Of note, at receiving operating characteristic analysis, a '% stress-to-rest' PFR ≤3 showed 71% sensitivity in unmasking the presence of significant coronary luminal narrowings. CONCLUSION: The present study shows that the assessment of stress-induced diastolic dysfunction with an ultrafast scintigraphic protocol can improve the accuracy in detection of significant ischaemic heart disease.

Regional heterogeneity in cardiac sympathetic innervation in acute myocardial infarction: relationship with myocardial oedema on magnetic resonance.

PURPOSE: To assess the relationships between myocardial structure and function on cardiac magnetic resonance (CMR) imaging and sympathetic tone on (123)I-metaiodobenzylguanidine ((123)I-MIBG) scintigraphy early after myocardial infarction (MI). METHODS: Ten patients underwent (123)I-MIBG and (99m)Tc-tetrofosmin rest cadmium zinc telluride scintigraphy 4 ± 1 days after MI. The segmental left ventricular (LV) relative radiotracer uptake of both (99m)Tc-tetrofosmin and early (123)I-MIBG was calculated. The day after scintigraphy, on CMR imaging, the extent of ischaemia-related oedema and of myocardial fibrosis (late gadolinium enhancement, LGE) was assessed. Accordingly, the extent of oedema and LGE was evaluated for each segment and segmental wall thickening determined. Based on LGE distribution, LV segments were categorized as "infarcted" (56 segments), "adjacent" (66 segments) or "remote" (48 segments). RESULTS: Infarcted segments showed a more depressed systolic wall thickening and greater extent of oedema than adjacent segments (p < 0.001) and remote segments (p < 0.001). Interestingly, while uptake of (99m)Tc-tetrofosmin was significantly depressed only in infarcted segments (p < 0.001 vs. both adjacent and remote segments), uptake of (123)I-MIBG was impaired not only in infarcted segments (p < 0.001 vs. remote) but also in adjacent segments (p = 0.024 vs. remote segments). At the regional level, after correction for (99m)Tc-tetrofosmin and LGE distribution, segmental (123)I-MIBG uptake (p < 0.001) remained an independent predictor of ischaemia-related oedema. CONCLUSION: After acute MI the regional impairment of sympathetic tone extends beyond the area of altered myocardial perfusion and is associated with myocardial oedema.

Evaluation of left ventricular diastolic function with a dedicated cadmium-zinc-telluride cardiac camera: comparison with Doppler echocardiography.

AIMS: To evaluate the relationships between measures of left ventricular (LV) filling dynamics at cadmium-zinc-telluride (CZT) imaging and indexes of LV diastolic function at transthoracic echocardiography. METHODS AND RESULTS: Two hundred and forty-seven patients underwent myocardial perfusion imaging at rest and after stress with a low-dose CZT protocol and a baseline transthoracic echocardiography study. All patients were submitted to invasive or computed coronary angiography. The peak filling rate (PFR) and the time to PFR (TPFR) were derived from gated CZT images as measures of LV filling dynamics. LV diastolic function was also evaluated at echocardiography and the presence of significantly increased LV filling pressures determined. Increased LV filling pressures at transthoracic echocardiography were evident in 103 (42%) patients. Interestingly, independently from the presence of coronary artery disease, there was a strict correlation between the presence and severity of LV diastolic dysfunction at echocardiography and CZT-derived measures of filling dynamics, i.e., PFR (P = 0.001) and TPFR (P = 0.001). At receiving operating characteristic analysis, a composite index of reduced PFR (≤2.11 end-diastolic volume s(-1)) and increased TPFR (>234 ms) showed a sensitivity of 84% and a specificity of 67% in unmasking the presence of elevated LV filling pressures at echocardiography. CONCLUSIONS: CZT-derived measures of LV filling dynamics correlate with echocardiographic parameters of diastolic function and may identify the presence of increased LV filling pressures.

Economic analysis including long-term risks and costs of alternative diagnostic strategies to evaluate patients with chest pain.

BACKGROUND: Diagnosis costs for cardiovascular disease waste a large amount of healthcare resources. The aim of the study is to evaluate the clinical and economic outcomes of alternative diagnostic strategies in low risk chest pain patients. METHODS: We evaluated direct and indirect downstream costs of 6 strategies: coronary angiography (CA) after positive troponin I or T (cTn-I or cTnT) (strategy 1); after positive exercise electrocardiography (ex-ECG) (strategy 2); after positive exercise echocardiography (ex-Echo) (strategy 3); after positive pharmacologic stress echocardiography (PhSE) (strategy 4); after positive myocardial exercise stress single-photon emission computed tomography with technetium Tc 99m sestamibi (ex-SPECT-Tc) (strategy 5) and direct CA (strategy 6). RESULTS: The predictive accuracy in correctly identifying the patients was 83,1% for cTn-I, 87% for cTn-T, 85,1% for ex-ECG, 93,4% for ex-Echo, 98,5% for PhSE, 89,4% for ex-SPECT-Tc and 18,7% for CA. The cost per patient correctly identified results $2.051 for cTn-I, $2.086 for cTn-T, $1.890 for ex-ECG, $803 for ex-Echo, $533 for PhSE, $1.521 for ex-SPECT-Tc ($1.634 including cost of extra risk of cancer) and $29.673 for CA ($29.999 including cost of extra risk of cancer). The average relative cost-effectiveness of cardiac imaging compared with the PhSE equal to 1 (as a cost comparator), the relative cost of ex-Echo is 1.5x, of a ex-SPECT-Tc is 3.1x, of a ex-ECG is 3.5x, of cTnI is x3.8, of cTnT is x3.9 and of a CA is 56.3x. CONCLUSION: Stress echocardiography based strategies are cost-effective versus alternative imaging strategies and the risk and cost of radiation exposure is void.