Feasibility and functional correlates of left atrial volume changes during stress echocardiography in chronic coronary syndromes.

An enlarged left atrial volume index (LAVI) at rest mirrors increased LA pressure and/or impairment of LA function. A cardiovascular stress may acutely modify left atrial volume (LAV) within minutes. Aim of this study was to assess the feasibility and functional correlates of LAV-stress echocardiography (SE) Out of 514 subjects referred to 10 quality-controlled labs, LAV-SE was completed in 490 (359 male, age 67 ± 12 years) with suspected or known chronic coronary syndromes (n = 462) or asymptomatic controls (n = 28). The utilized stress was exercise in 177, vasodilator in 167, dobutamine in 146. LAV was measured with the biplane disk summation method. SE was performed with the ABCDE protocol. The intra-observer and inter-observer LAV variability were 5% and 8%, respectively. ∆-LAVI changes (stress-rest) were negatively correlated with resting LAVI (r = - 0.271, p < 0.001) and heart rate reserve (r = -.239, p < 0.001). LAV-dilators were defined as those with stress-rest increase ≥ 6.8 ml/m2, a cutoff derived from a calculated reference change value above the biological, analytical and observer variability of LAVI. LAV dilation occurred in 56 patients (11%), more frequently with exercise (16%) and dipyridamole (13%) compared to dobutamine (4%, p < 0.01). At multivariable logistic regression analysis, B-lines ≥ 2 (OR: 2.586, 95% CI = 1.1293-5.169, p = 0.007) and abnormal contractile reserve (OR: 2.207, 95% CI = 1.111-4.386, p = 0.024) were associated with LAV dilation. In conclusion, LAV-SE is feasible with high success rate and low variability in patients with chronic coronary syndromes. LAV dilation is more likely with reduced left ventricular contractile reserve and pulmonary congestion.

Lung Ultrasound and Pulmonary Congestion During Stress Echocardiography.

OBJECTIVES: The purpose of this study was to assess the functional and prognostic correlates of B-lines during stress echocardiography (SE). BACKGROUND: B-profile detected by lung ultrasound (LUS) is a sign of pulmonary congestion during SE. METHODS: The authors prospectively performed transthoracic echocardiography (TTE) and LUS in 2,145 patients referred for exercise (n = 1,012), vasodilator (n = 1,054), or dobutamine (n = 79) SE in 11 certified centers. B-lines were evaluated in a 4-site simplified scan (each site scored from 0: A-lines to 10: white lung for coalescing B-lines). During stress the following were also analyzed: stress-induced new regional wall motion abnormalities in 2 contiguous segments; reduced left ventricular contractile reserve (peak/rest based on force, ≤2.0 for exercise and dobutamine, ≤1.1 for vasodilators); and abnormal coronary flow velocity reserve ≤2.0, assessed by pulsed-wave Doppler sampling in left anterior descending coronary artery and abnormal heart rate reserve (peak/rest heart rate) ≤1.80 for exercise and dobutamine (≤1.22 for vasodilators). All patients completed follow-up. RESULTS: According to B-lines at peak stress patients were divided into 4 different groups: group I, absence of stress B-lines (score: 0 to 1; n = 1,389; 64.7%); group II, mild B-lines (score: 2 to 4; n = 428; 20%); group III, moderate B-lines (score: 5 to 9; n = 209; 9.7%) and group IV, severe B-lines (score: ≥10; n = 119; 5.4%). During median follow-up of 15.2 months (interquartile range: 12 to 20 months) there were 38 deaths and 28 nonfatal myocardial infarctions in 64 patients. At multivariable analysis, severe stress B-lines (hazard ratio [HR]: 3.544; 95% confidence interval [CI]: 1.466 to 8.687; p = 0.006), abnormal heart rate reserve (HR: 2.276; 95% CI: 1.215 to 4.262; p = 0.010), abnormal coronary flow velocity reserve (HR: 2.178; 95% CI: 1.059 to 4.479; p = 0.034), and age (HR: 1.031; 95% CI: 1.002 to 1.062; p = 0.037) were independent predictors of death and nonfatal myocardial infarction. CONCLUSIONS: Severe stress B-lines predict death and nonfatal myocardial infarction. (Stress Echo 2020-The International Stress Echo Study [SE2020]; NCT03049995).

Functional, Anatomical, and Prognostic Correlates of Coronary Flow Velocity Reserve During Stress Echocardiography.

BACKGROUND: The assessment of coronary flow velocity reserve (CFVR) in left anterior descending coronary artery (LAD) expands the risk stratification potential of stress echocardiography (SE) based on stress-induced regional wall motion abnormalities (RWMA). OBJECTIVES: The purpose of this study was to assess the feasibility and functional correlates of CFVR. METHODS: This prospective, observational, multicenter study initially screened 3,410 patients (2,061 [60%] male; age 63 ± 11 years; ejection fraction 61 ± 9%) with known or suspected coronary artery disease and/or heart failure. All patients underwent SE (exercise, n = 1,288; vasodilator, n = 1,860; dobutamine, n = 262) based on new or worsening RWMA in 20 accredited laboratories of 8 countries. CFVR was calculated as the stress/rest ratio of diastolic peak flow velocity pulsed-Doppler assessment of LAD flow. A subset of 1,867 patients was followed up. RESULTS: The success rate for CFVR on LAD was 3,002 of 3,410 (feasibility = 88%). Reduced (≤2.0) CFVR was found in 896 of 3,002 (30%) patients. At multivariable logistic regression analysis, inducible RWMA (odds ratio [OR]: 6.5; 95% confidence interval [CI]: 4.9 to 8.5; p < 0.01), abnormal left ventricular contractile reserve (OR: 3.4; 95% CI: 2.7 to 4.2; p < 0.01), and B-lines (OR: 1.5; 95% CI: 1.1 to 1.9; p = 0.01) were associated with reduced CFVR. During a median follow-up time of 16 months, 218 events occurred. RWMA (hazard ratio: 3.8; 95% CI: 2.3 to 6.3; p < 0.001) and reduced CFVR (hazard ratio: 1.5; 95% CI: 1.1 to 2.2; p = 0.009) were independently associated with adverse outcome. CONCLUSIONS: CFVR is feasible with all SE protocols. Reduced CFVR is often accompanied by RWMA, abnormal LVCR, and pulmonary congestion during stress, and shows independent value over RWMA in predicting an adverse outcome.

Quality control of B-lines analysis in stress Echo 2020.

BACKGROUND: The effectiveness trial "Stress echo (SE) 2020" evaluates novel applications of SE in and beyond coronary artery disease. The core protocol also includes 4-site simplified scan of B-lines by lung ultrasound, useful to assess pulmonary congestion. PURPOSE: To provide web-based upstream quality control and harmonization of B-lines reading criteria. METHODS: 60 readers (all previously accredited for regional wall motion, 53 B-lines naive) from 52 centers of 16 countries of SE 2020 network read a set of 20 lung ultrasound video-clips selected by the Pisa lab serving as reference standard, after taking an obligatory web-based learning 2-h module ( http://se2020.altervista.org ). Each test clip was scored for B-lines from 0 (black lung, A-lines, no B-lines) to 10 (white lung, coalescing B-lines). The diagnostic gold standard was the concordant assessment of two experienced readers of the Pisa lab. The answer of the reader was considered correct if concordant with reference standard reading ±1 (for instance, reference standard reading of 5 B-lines; correct answer 4, 5, or 6). The a priori determined pass threshold was 18/20 (≥ 90%) with R value (intra-class correlation coefficient) between reference standard and recruiting center) > 0.90. Inter-observer agreement was assessed with intra-class correlation coefficient statistics. RESULTS: All 60 readers were successfully accredited: 26 (43%) on first, 24 (40%) on second, and 10 (17%) on third attempt. The average diagnostic accuracy of the 60 accredited readers was 95%, with R value of 0.95 compared to reference standard reading. The 53 B-lines naive scored similarly to the 7 B-lines expert on first attempt (90 versus 95%, p = NS). Compared to the step-1 of quality control for regional wall motion abnormalities, the mean reading time per attempt was shorter (17 ± 3 vs 29 ± 12 min, p < .01), the first attempt success rate was higher (43 vs 28%, p < 0.01), and the drop-out of readers smaller (0 vs 28%, p < .01). CONCLUSIONS: Web-based learning is highly effective for teaching and harmonizing B-lines reading. Echocardiographers without previous experience with B-lines learn quickly.

Late myocardial ischemia with ST-segment elevation after negative dobutamine stress echocardiography in a patient with normal coronary arteries.

Late complications after pharmacological stress echocardiography are infrequent but potentially dreadful events. We report the case of a 80-year-old woman admitted to hospital for rest chest pain with trivial troponin increase, normal left ventricular function and no significant ECG changes. A dobutamine stress echocardiography was performed for diagnostic purpose, with a negative result. About 30 min after the end of dobutamine infusion, she developed ST-segment elevation in inferior leads associated with chest pain and left ventricular dyssynergy, promptly resolved by sublingual nitrates. Subsequently, angiography documented the absence of significant coronary stenoses. The following clinical course was uneventful. Transient myocardial ischemia was likely due to dobutamine-induced coronary spasm. The case emphasizes the utility of routine, long-lasting monitoring of patients after stress echocardiography, even if negative, to counteract possible late life-threatening complications.

Value of tissue Doppler imaging for risk stratification of patients with chronic systolic heart failure with or without restrictive mitral flow.

AIMS: The aim of this study was to assess the prognostic value of tissue Doppler imaging (TDI) in patients with chronic systolic heart failure (HF) with or without restrictive mitral flow (RMF). METHODS AND RESULTS: Echocardiograms were obtained in 378 patients with chronic systolic HF [ejection fraction (EF) < or = 45%] in sinus rhythm. Restrictive mitral flow was defined by an E wave deceleration time (EDT) < or = 140 ms. Tissue Doppler imaging early (Em) diastolic and systolic (Sm) velocities were measured at the mitral annulus. Patients were followed-up for a median of 32 months. Endpoints were all-cause mortality and the combination of death or HF hospitalization. Mean left ventricular EF was 32 +/- 8%. Restrictive mitral flow and TDI annular velocities were all univariate predictors of the endpoints. Ejection fraction <25% was the only multivariate predictor of all-cause mortality. E wave deceleration time and Em < 8 cm/s were independently associated with the combined endpoint of death or HF hospitalization. At 48 months, survival was 61% in patients with RMF and 82% in patients with non-RMF (log-rank: 21.6; P < 0.0001). When patients were stratified according to Em at or above 8 cm/s or below 8 cm/s, those with RMF and Em < 8 cm/s exhibited the worst survival (log-rank: 27.16; P < 0.0001). Patients with Sm < or = 6 cm/s had a 58% survival rate, whereas it was 82% in patients with Sm > 6 cm/s (log-rank: 12.73; P = 0.0004). CONCLUSION: Doppler annular velocities provided useful information for prognostication of patients with systolic HF. Particularly, categorization of patients according to Em velocities allowed us to further stratify patients with RMF and non-RMF.

Non-obstructive prosthetic aortic valve thrombosis presenting with acute myocardial infarction and stroke in a patient with inadequate low-molecular-weight heparin treatment. The unlucky patient and the (pseudo)prudent physician.

Non-obstructive prosthetic valve thrombosis is a rare and underestimated complication in patients with left-sided mechanical heart valves. Systemic embolisation, mainly involving the cerebral circulation, often represents the first clinical manifestation. We report a case of multiple, successive embolizations in the coronary and cerebral circulation, presenting with an acute myocardial infarction and stroke in a patient with latent, non-obstructive thrombosis of a mechanical bileaflet aortic valve. Because of scheduled urological surgery, chronic vitamin K antagonist treatment had previously been discontinued and replaced with low-molecular-weight heparin, at inadequate dosage. Following coronary arteriography, brain computed tomography scan and transoesophageal echocardiography, thrombolysis was performed successfully. This case emphasises the utility of performing transoesophageal echocardiography routinely in the presence of ischaemic signs in patients with mechanical heart valves. In patients requiring discontinuation of oral anticoagulant therapy, accurate management and continuous monitoring of alternative medications are needed in order to avoid severe thromboembolic complications.

A computer protocol to evaluate subjects with chest pain in the emergency department: a multicenter study.

OBJECTIVE: Chest pain is a frequent cause of medical admission to the emergency department and the main differential diagnosis is between coronary and non-coronary chest pain. We elaborated a computer protocol for the management of patients with chest pain. METHODS: The computer protocol was made of three sections according to clinical, electrocardiographic and biochemical data. Each section was coded by a letter indicating the probability of coronary chest pain for each section. The combination of the three letters formed a score string used to assign patients to four subgroups of overall probability of coronary chest pain (low, medium-low, medium-high, and high). Low-probability patients were discharged from the emergency department, whereas high-probability patients were admitted to the coronary care unit. The medium-probability patients underwent further evaluation by means of a stress test and were re-classified as having a final low probability (negative test) or high probability (positive test). RESULTS: We evaluated 472 patients (mean age 64 years, range 18-97 years; 47% female). The incidence of coronary events in patients with low, medium-low, medium-high and high overall probability was 1.9, 12.8,13.5 and 68.0%, respectively (P < 0.05). The positive and negative predictive values of the protocol were 64.7 and 97.1%, respectively. CONCLUSIONS: Our computer protocol represents a reliable method for the management of patients with chest pain and a non-diagnostic electrocardiogram.

[Feasibility and accuracy of a rapid evaluation of the abdominal aorta during routine transthoracic echocardiography]. / Fattibilità ed accuratezza di una rapida valutazione dell'aorta addominale durante l'esame ecocardiografico transtoracico.

BACKGROUND: Mass screening for occult abdominal aortic aneurysm is not realistic for the low prevalence of this condition in the general population. Screening in a high-risk population, especially during standard echocardiographic examination, could be more cost-effective than a separate screening program. The aim of this study was to evaluate the feasibility and accuracy of a rapid evaluation (examination arbitrary time-limit of 2 min) of the abdominal aorta at the end of a routine transthoracic echocardiographic examination. METHODS: One hundred and eighty-one male patients (average age 61 years, range 45-79 years) were studied. A subgroup of 83 patients was also blindly examined by a radiologist for diagnostic accuracy evaluation. RESULTS: Abdominal aortic aneurysm was defined as an aortic diameter enlargement > or = 3.0 cm. Sixteen patients were excluded due to suboptimal aortic wall imaging or to examination lasting > 2 min (feasibility 91%). An occult aneurysm was found in 7 patients (3.8%). As regards the presence/absence of aneurysms in the subgroup of patients undergoing double examination, sensitivity and specificity were 80 and 100% respectively. CONCLUSIONS: Rapid evaluation of the abdominal aorta for aortic screening during routine echocardiography is highly feasible and accurate without any significant prolongation of the examination time and should therefore be routinely performed during standard examination.

[Evaluation of the appropriateness of prescribing echocardiography]. / La valutazione dell'appropriatezza della prescrizione dell'ecocardiogramma.

BACKGROUND: We evaluated the appropriateness of indications to echocardiography for ambulatory patients performed during 4 weeks in 21 laboratories in Tuscany and Umbria, Italy. METHODS: We collected the following data: the appropriateness of the prescription (according to the guidelines of the Italian Federation of Cardiology), the prescribing physician (cardiologist vs non-cardiologist), the synthetic result (normal vs abnormal) and the clinical utility (useful vs useless) of each exam. RESULTS: We evaluated 2848 prescriptions (patients: 1450 males, 1398 females; mean age 62 years, range 15-90 years). The indications to test were of class I (appropriate) in 43.6%, of class II (of doubtfully appropriateness) in 36.8% and of class III (inappropriate) in 19.6% of the cases. In 60.8% of the cases the exam was considered abnormal. In particular, an abnormal result was found in 83.8% of class I, in 56.6% of class II and in 17.8% of class III exams (p < 0.05). The exam was considered useful in 51.1% of the cases. In particular, a useful result was found in 78.9% of class I, in 39% of class II and in 12.1% of class III exams (p < 0.05). Cardiologists prescribed 856/2848 tests (30%). Their indications were of class I in 58.8%, of class II in 29.8% and of class III in 11.4% of the cases vs 37, 39.9 and 23.1% of non-cardiologists' prescriptions (p < 0.05). Abnormal findings were found in 74.3% of cardiologist- vs 55% of non-cardiologist-prescribed examinations (odds ratio 2.45, 95% confidence interval 2.04-2.92; p < 0.05); similarly, clinically useful information could be derived from 63.1% of cardiologist- vs 46% of non-cardiologist-prescribed examinations (odds ratio 2.07, 95% confidence interval 1.75-2.45; p < 0.05). CONCLUSIONS: In Tuscany and Umbria, Italy, about half of the prescriptions for echocardiography can be considered inappropriate; appropriately prescribed exams more often provide abnormal and useful results; cardiologist-prescribed exams are significantly more appropriate, abnormal and useful.

Quantitative Texture Analysis in Two-Dimensional Echocardiography: Application to the Diagnosis of Myocardial Hemochromatosis.

BACKGROUND: Myocardial reflectivity is abnormally increased in patients with thalassemia major under transfusion treatment, probably due to myocardial iron deposits and/or secondary structural changes. Such increased reflectivity has been detected by both qualitative and subjective analysis of two-dimensional echocardiographic (2-D echo) images and quantitative assessment of integrated backscatter amplitude with noncommercially available ultrasound prototypes. The purpose of this study was to assess the acoustic properties of myocardium in patients with beta-thalassemia major and iron overload by means of quantitative computerized offline textural analysis of conventionally recorded 2-D echo images, and to compare textural data with other qualitative (visual assessment) and quantitative (ultrasound backscatter analysis) approaches for myocardial ultrasound tissue characterization simultaneously applied to these patients. METHODS AND RESULTS: Thirty-five young patients with thalassemia major, without clinical signs of cardiac failure, and 20 age and sex matched normal controls were studied by echocardiography. Each patient was receiving blood transfusion every 2-3 weeks. Two-dimensional echo images, obtained with a commercially available echocardiograph using the parasternal long-axis view, were digitized off line and analyzed by first and second order texture algorithms applied to regions of interest in the myocardium (septal and posterior wall). The mean gray level value was higher in thalassemic patients than in controls on both the septum (110 +/- 25 vs 57 +/- 13, arbitrary units on a 0-255 scale; P < 0.01) and posterior wall (91 +/- 25 vs 67 +/- 18; P < 0.01). Among second order statistical parameters, contrast and angular second moment significantly (P < 0.01) differentiated septal and posterior walls of patients and controls. In thalassemic patients, no consistent correlation was found between wall texture parameters and hematologic (years of transfusions and chelation, number of transfusions), 2-D echo (posterior wall thickness, left ventricular end-diastolic diameter), and Doppler (transmitral E/A waves ratio) parameters. Myocardial walls with visually assessed increased echo reflectivity showed a trend toward higher values of mean gray level when compared with myocardial segments with qualitatively assessed normal reflectivity (septum: 121 +/- 26 vs 106 +/- 24; posterior wall: 105 +/- 23 vs 87 +/- 23). Although radiofrequency integrated backscatter has been demonstrated to be capable of identifying thalassemic patients, no significant correlation was found between mean gray level (by texture analysis) and radiofrequency data (septum: r = 0.03; posterior wall: r = 0.09; P = NS for both). CONCLUSIONS: Myocardial walls affected by hemochromatosis show ultrasound image texture alterations that may be quantified with digital image analysis techniques and appear mostly unrelated to hematologic and conventional, as well as radiofrequency-based, echocardiographic parameters. These changes in quantitatively evaluated echo reflectivity are present even before the development of clinical and echocardiographic signs of cardiac dysfunction. (ECHOCARDIOGRAPHY, Volume 13, January 1996)