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.

Echocardiographic Biventricular Coupling Index to Predict Precapillary Pulmonary Hypertension.

BACKGROUND: Pulmonary hypertension (PH) is a frequent and detrimental condition. Right heart catheterization (RHC) is the gold standard to identify PH subtype (precapillary from postcapillary PH) and is key for treatment allocation. In this study, the novel echocardiographic biventricular coupling index (BCI), based on the ratio between right ventricular stroke work index and left ventricular E/E' ratio, was tested for the discrimination of PH subtype using RHC as the comparator. METHODS: BCI was derived in 334 consecutive patients who underwent transthoracic echocardiography and RHC for all indications. BCI was then tested in a validation cohort of 1,349 patients. RESULTS: The accuracy of BCI to identify precapillary PH was high in the derivation cohort (area under the curve, 0.82; 95% CI, 0.78-0.88; P < .001; optimal cut point, 1.9). BCI identified patients with precapillary PH with high accuracy also in the validation cohort (area under the curve, 0.87 [95% CI, 0.85-0.89; P < .001]; subgroup with PH: area under the curve, 0.91 [95% CI, 0.89-0.93; P < .001]; cut point, 1.9; sensitivity, 82%; specificity, 89%; positive predictive value, 77%; negative predictive value, 92%). BCI outperformed both the D'Alto score (Z = 3.56; difference between areas = 0.05; 95% CI, 0.02-0.07; P < .001) and the echocardiographic pulmonary-to-left atrial ratio index (Z = 2.88; difference between areas = 0.02; 95% CI, 0.01-0.04; P = .004). CONCLUSIONS: BCI is a novel, noninvasive index based on routinely available echocardiographic parameters that identifies with high accuracy patients with precapillary PH. BCI may be of value in the screening workup of patients with PH.

CMR predictors of secondary moderate to severe mitral regurgitation and its additive prognostic role in previous myocardial infarction.

BACKGROUND: We aimed to determine predictors and the additive prognostic role of moderate to severe (MS) ischemic mitral regurgitation (MR) in myocardial infarction (MI). METHODS: Four hundred twenty-two patients with previous MI underwent cardiac magnetic resonance (CMR) imaging for the assessment of left ventricular (LV) ejection fraction (EF), end-diastolic (EDV) and end-systolic volume (ESV), sphericity index, wall motion score index (WMSI), and late gadolinium enhancement (LGE). Echocardiography was performed to assess MR. RESULTS: Thirty-eight had from moderate to severe MR (MS-MR group) and 384 did not (No MS-MR group). The S-MR group had higher LV volumes, sphericity index, WMSI, and LGE extent, and lower LVEF. At univariate logistic regression analysis, dilated volumes, SI >0.43, dyskinesia of inferolateral wall, papillary muscle (PM)-LGE, and LGE extent >16% were associated with MS-MR. At multivariate analysis, only SI (OR=5.7) and PM-LGE (OR=3) were independently associated with MS-MR. Considering only patients without LV dilatation, only dyskinesia in the inferolateral wall was a predictor of MS-MR (OR 34.8). Thirty cardiac events (cardiac death, appropriate implantable cardioverter-defibrillator firing, and resuscitated cardiac arrest) occurred during a median follow-up of 1,276 days. After adjusting the prognostic variables at univariate analysis by age (>65 years) and selecting those that were significant (EDV > 95 ml/m2, ESV >53 ml/m2, EF <30%, WMSI >1.65, LGE >12%, S-MR), only WMSI >1.65 and MS-MR remained an independent predictor of cardiac events. CONCLUSIONS: Increased WMSI and PM-LGE in the overall population and inferolateral dyskinesia in patients without ESV dilatation are predictors of MS-MR; MS-MR and elevated WMSI have independent negative prognostic value.

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.

A novel echocardiographic method for estimation of pulmonary artery wedge pressure and pulmonary vascular resistance.

AIMS: This study aimed to evaluate a novel echocardiographic algorithm for quantitative estimation of pulmonary artery wedge pressure (PAWP) and pulmonary vascular resistance (PVR) in patients with heart failure and pulmonary hypertension (PH) scheduled to right heart catheterization (RHC). METHODS AND RESULTS: In this monocentric study, 795 consecutive patients (427 men; age 68.4 ± 12.1 years) undergoing echocardiography and RHC were evaluated. Multiple regression analysis was performed to identify echocardiographic predictors of PAWP and PVR measured by RHC in the derivation group (the first 200 patients). The diagnostic accuracy of the model was then tested in the validation group (the remaining 595 patients). PH was confirmed by RHC in 507 (63.8%) patients, with 192 (24.2%) cases of precapillary PH, 248 (31.2%) of postcapillary PH, and 67 (8.4%) of combined PH. At regression analysis, tricuspid regurgitation maximal velocity, mitral E/e' ratio, left ventricular ejection fraction, right ventricular fractional area change, inferior vena cava diameter, and left atrial volume index were included in the model (R = 0.8, P < 0.001). The model showed a high diagnostic accuracy in estimating elevated PAWP (area under the receiver operating characteristic curve = 0.97, 92% sensitivity, and 93% specificity, P < 0.001) and PVR (area under the receiver operating characteristic curve = 0.96, 89% sensitivity, and 92% specificity, P < 0.001), outperforming 2016 American Society of Echocardiography/European Association of Cardiovascular Imaging recommendations (P < 0.001) and Abbas' equation (P < 0.001). Bland-Altman analysis showed satisfactory limits of agreement between echocardiography and RHC for PAWP (bias 0.7, 95% confidence interval -7.3 to 8.7) and PVR (bias -0.1, 95% confidence interval -2.2 to 1.9 Wood units), without indeterminate cases. CONCLUSIONS: A novel quantitative echocardiographic approach for the estimation of PAWP and PVR has high diagnostic accuracy in patients with heart failure and PH.

A simple echocardiographic score to rule out cardiac amyloidosis.

BACKGROUND: Early diagnosis of cardiac amyloidosis (CA) is warranted to initiate specific treatment and improve outcome. The amyloid light chain (AL) and inferior wall thickness (IWT) scores have been proposed to assess patients referred by haematologists or with unexplained left ventricular (LV) hypertrophy, respectively. These scores are composed of 4 or 5 variables, respectively, including strain data. METHODS: Based on 2 variables common to the AL and IWT scores, we defined a simple score named AMYLoidosis Index (AMYLI) as the product of relative wall thickness (RWT) and E/e' ratio, and assessed its diagnostic performance. RESULTS: In the original cohort (n = 251), CA was ultimately diagnosed in 111 patients (44%). The 2.22 value was selected as rule-out cut-off (negative likelihood ratio [LR-] 0.0). In the haematology subset, AL CA was diagnosed in 32 patients (48%), with 2.36 as rule-out cut-off (LR- 0.0). In the hypertrophy subset, ATTR CA was diagnosed in 79 patients (43%), with 2.22 as the best rule-out cut-off (LR- 0.0). In the validation cohort (n = 691), the same cut-offs proved effective: indeed, there were no patients with CA in the whole population or in the haematology or hypertrophy subsets scoring < 2.22, <2.36 or < 2.22, respectively. CONCLUSIONS: The AMYLI score (RWT*E/e') may have a role as an initial screening tool for CA. A < 2.22 value excludes the diagnosis in patients undergoing a diagnostic screening for CA, while a < 2.36 and a < 2.22 value may be better considered in the subsets with suspected cardiac AL amyloidosis or unexplained hypertrophy, respectively.

Global Right Heart Assessment with Speckle-Tracking Imaging Improves the Risk Prediction of a Validated Scoring System in Pulmonary Arterial Hypertension.

BACKGROUND: Right ventricular (RV) function and right atrial (RA) remodeling are major determinants of outcome in pulmonary arterial hypertension (PAH). Strain echocardiography is emerging as a valuable approach for the study of RV and RA function. We sought to assess the incremental prognostic value of serial combined speckle-tracking examination of right chambers in newly diagnosed therapy-naïve PAH patients. METHODS: The study endpoint was a composite of all-cause mortality, hospitalizations due to worsening PAH, and initiation of parenteral prostanoids. Patients were assessed at baseline and at first revaluation after initiation of treatment. Right ventricular free-wall longitudinal strain (FWLS) and RA peak atrial longitudinal strain (PALS) were used as measures of RV and RA function. RESULTS: Eighty-three patients were included. Mean RV-FWLS and RA-PALS were -13.9% ± 6.1% and 23.1% ± 11.4%. The best performing prognostic score among the Comparative, Prospective Registry of Newly Initiated Therapies for Pulmonary Hypertension, French Pulmonary Hypertension Registry, and Registry to Evaluate Early and Long-Term Pulmonary Arterial Hypertension Disease Management (REVEAL) scores was the REVEAL (area under the curve = 0.79, P < .001). With the identified cutoffs, both RV-FWLS (hazard ratio for RV-FWLS < -13.2% = 0.366; 95% CI, 0.159-0.842; P = .018) and RA-PALS (hazard ratio for RA-PALS > 20% = 0.399; 95% CI, 0.176-0.905; P = .028) were independently associated with the primary outcome after correction for the REVEAL score. The combined assessment of RV-FWLS and RA-PALS in addition to the REVEAL score determined a net improvement in prediction of 0.439 (95% CI, 0.070-0.888, P = .04). At 5 months (interquartile range, 4-8) of follow-up, RV-FWLS and RA-PALS improved significantly only in patients free from the primary outcome (P < .001 and P = .001, respectively). CONCLUSIONS: The combined assessment of RV-FWLS and RA-PALS determined an improvement in outcome prediction of validated prognostic risk scores and should be considered within the multiparametric evaluation of patients with PAH.

Ticagrelor Enhances Release of Anti-Hypoxic Cardiac Progenitor Cell-Derived Exosomes Through Increasing Cell Proliferation In Vitro.

Despite the widespread clinical use of cardioprotection by long-term direct antagonism of P2Y12 receptor, underlying mechanisms are unclear. Here, we identify how release of pro-survival exosomes from human cardiac-derived mesenchymal progenitor cells (hCPCs) is regulated by clinically relevant dose of ticagrelor (1 µM), an oral selective and reversible non-thienopyridine P2Y12 inhibitor. Ticagrelor-induced enhancement of exosome levels is related to increased mitotic activity of hCPCs. We show a drug-response threshold above which the effects on hCPCs are lost due to higher dose of ticagrelor and larger adenosine levels. While it is known that pan-Aurora kinase inhibitor halts cell proliferation through dephosphorylation of histone H3 residue Ser10, we demonstrate that it also prevents ticagrelor-induced effects on release of cardiac progenitor cell-derived exosomes delivering anti-apoptotic HSP70. Indeed, sustained pre-treatment of cardiomyocytes with exosomes released from explant-derived hCPCs exposed to low-dose ticagrelor attenuated hypoxia-induced apoptosis through acute phosphorylation of ERK42/44. Our data indicate that ticagrelor can be leveraged to modulate release of anti-hypoxic exosomes from resident hCPCs.

Usefulness of dual imaging stress echocardiography for the diagnosis of coronary allograft vasculopathy in heart transplant recipients.

BACKGROUND: Coronary allograft vasculopathy (CAV) is the main factor limiting long-term survival after cardiac transplantation. Dual imaging stress echocardiography with wall motion and Doppler-derived coronary flow reserve (CRF) of the left anterior descending artery (LAD) is a state-of-the-art methodology during dipyridamole stress echocardiography (DiSE). This study involving 74 heart transplanted patients has the purpose to assess the diagnostic value of dipyridamole stress echocardiography with evaluation of wall motion (WM) and Doppler-derived coronary flow reserve for the diagnosis of coronary allograft vasculopathy. METHODS AND RESULTS: All patients underwent DiSE and coronary angiography. Moderate-severe CAV was defined according to International Society of Heart and Lung Transplant (ISHLT) recommended nomenclature for CAV, and CFR < 2 was considered to be impaired. Moderate-severe CAV was present in 11 patients. WM analysis revealed four patients (5%) with rest WM abnormalities. CFR analysis revealed that 40 (54%) individuals had an abnormal result. The combined evaluation of WM analysis and CFR resulted in a sensitivity of 72.7% (95% CI: 39.3 to 92.6%), a specificity of 49.2% (95% CI: 36.5 to 61.9%), a positive predictive value of 20% (95% CI: 9.6 to 36.1%), and negative predictive value of 91.1% (95% CI: 75.1 to 97.6%) for the diagnosis of CAV. CONCLUSIONS: Our results support the inclusion of DiSE performance in Heart transplant follow up protocol. The addition of CFR evaluation offers valuable information to the angiography findings in the detection of CAV and could be helpful in selected patients to adjust the time and indications of coronary angiography.

Cheyne-Stokes respiration related oscillations in cardiopulmonary hemodynamics in patients with heart failure.

BACKGROUND: Although Cheyne-Stokes respiration (CSR) is an oscillatory phenomenon, the direct effects of cyclical hyperventilation and apnea on cardiopulmonary hemodynamics have been poorly investigated. The aim of the study was to examine the echocardiographic changes associated with CSR phases in a group of patients with systolic heart failure (HF) and daytime CSR. METHODS: 14 HF patients (age 70 ±â€¯9 years, LVEF 24 ±â€¯5) underwent a thorough clinical evaluation, 24-h respiratory polygraphy, chemoreflex evaluation by rebreathing technique and neuro-hormonal assessment. Furthermore, they received a simultaneous echocardiographic and respiratory monitoring embedding the respiratory signal in the echocardiographic machine. RESULTS: All patients had daytime CSR (diurnal apnea-hypopnea index, AHI: 18.5, interquartile range: 15.3-39.5 events/h). Systolic pulmonary artery pressure and pulmonary vascular resistances (PVR) increased from hyperventilation to apnea (H 45.3 ±â€¯11.4 vs A 52.4 ±â€¯13.8 mmHg, p = 0.004, and H 3.3 ±â€¯2.5 vs A 5.1 ±â€¯3.2 Wood units, p = 0.0003, respectively), while acceleration time of the pulmonary artery decreased (H 110.1 ±â€¯19.8 vs A 92.0 ±â€¯19.9 ms, p = 0.001). During apnea a reduction of right and left ventricular outflow tract VTI (H 12.8 ±â€¯4.9 versus A 9.9 ±â€¯3.1, p = 0.002 and H 26.9 ±â€¯8.8 versus A 22.8 ±â€¯7.9 mm, p = 0.006, respectively), and a reduction in tricuspid annular plane systolic excursion (H 15.9 ±â€¯4.4 versus A 14.4 ±â€¯4.1 mm, p = 0.005) were also observed. Notably, PVR variation strongly correlated with chemosensitivity to hypercapnia (R = 0.89, p = 0.0004) and plasma norepinephrine level (R = 0.78, p = 0.003). CONCLUSIONS: In HF patients with CSR, an increase in pulmonary pressure and pulmonary vascular resistances was observed during apnea. Pulmonary vasoconstriction strongly correlated with chemosensitivity to hypercapnia and indexes of adrenergic activation.

Left ventricular ejection fraction for risk stratification in chronic systolic heart failure.

BACKGROUND: Left ventricular ejection fraction (LVEF) represents the most used measure of cardiac systolic function. Different cut-offs have been proposed to classify patients with systolic dysfunction, and to inform therapy decision-making. METHODS: Consecutive outpatients with systolic heart failure (HF; LVEF <50%) were prospectively enrolled and underwent a baseline characterization. The prognostic value of LVEF and LVEF cut-offs was made with regards to the prediction of all-cause and cardiovascular death. RESULTS: Out of 2160 patients, 71% had LVEF <40%, and 61% had ≤35%. Over a 26-month median follow-up (interquartile interval 12-39), patients with LVEF ≤35% (log-rank 31.11 and 59.48, respectively; both p < 0.001) and <40% (log-rank 24.51 and 41.77, respectively; both p < 0.001) had a significantly worse prognosis for all-cause and cardiovascular death. LVEF independently predicted both endpoints in a strong prognostic model including age, sex, ischaemic aetiology, N-terminal fraction of pro-B-type natriuretic peptide, New York Heart Association class III-IV, several comorbidities and therapies. Receiver operating characteristics curves identified LVEF values 32% and 31% as the best cut-offs for the two endpoints. The 40% and lower cut-offs (35%, 32% or 31%) were independent predictors of all-cause and cardiovascular death (p < 0.001 in all cases). The 35% cut-off had a lower Akaike's Information Criterion value than 40%, denoting more accurate risk stratification. CONCLUSIONS: LVEF is an independent predictor of all-cause and cardiovascular mortality in chronic systolic HF. The 35% LVEF cut-off displays a better combination of sensitivity and specificity than the 40% cut-off for outcome prediction, although both hold independent prognostic value.

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.