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Aims In functional tricuspid regurgitation (FTR) patients, tricuspid leaflet tethering and relatively low jet velocity could result in proximal flow geometry distortions that lead to underestimation of TR. Application of correction factors on two-dimensional (2D) proximal isovelocity surface area (PISA) equation may increase its reliability. This study sought to evaluate the impact of the corrected 2D PISA method in quantifying FTR severity. Methods and results In 102 patients with FTR, we compared both conventional and corrected 2D PISA measurements of effective regurgitant orifice area [EROA vs. corrected (EROAc)] and regurgitant volume (RegVol vs. RegVolc) with those obtained by volumetric method (VM) using three-dimensional echocardiography (3DE), as reference. Both EROAc and RegVolc were larger than EROA (0.29 ± 0.26 vs. 0.22 ± 0.21 cm2; P < 0.001) and RegVol (24.5 ± 20 vs. 18.5 ± 14.25 mL; P < 0.001), respectively. Compared with VM, both EROAc and RegVolc resulted more accurate than EROA [bias = −0.04 cm2, limits of agreement (LOA) ± 0.02 cm2 vs. bias = −0.15 cm2, LOA ± 0.31 cm2] and RegVol (bias = −3.29 mL, LOA ± 2.19 mL vs. bias = −10.9 mL, LOA ± 13.5 mL). Using EROAc and RegVolc, 37% of patients were reclassified in higher grades of FTR severity. Corrected 2D PISA method led to a higher concordance of TR severity grade with the VM method (ĸ = 0.84 vs. ĸ = 0.33 for uncorrected PISA, P < 0.001). Conclusion Compared with VM by 3DE, the conventional PISA underestimated FTR severity in about 50% of patients. Correction for TV leaflets tethering angle and lower velocity of FTR jet improved 2D PISA accuracy and reclassified more than one-third of the patients.

BackgroundBoth secondary tricuspid regurgitation (STR) and heart failure with preserved ejection fraction (HFpEF) are relevant public health problems in the elderly population, presenting with potential overlaps and sharing similar risk factors. However, the impact of severe STR on hemodynamics and cardiorespiratory adaptation to exercise in HFpEF remains to be clarified.AimTo explore the impact of STR on exercise hemodynamics and cardiorespiratory adaptation in HFpEF.MethodsWe analyzed invasive hemodynamics and gas-exchange data obtained at rest and during exercise from HFpEF patients with severe STR (HFpEF-STR), compared with 1:1 age-, sex-, and body mass index (BMI)- matched HFpEF patients with mild or no STR (HFpEF-controls).ResultsTwelve HFpEF with atrial-STR (mean age 72 years, 92% females, BMI 28 Kg/m2) and 12 HFpEF-controls patients were analyzed. HFpEF-STR had higher (p < 0.01) right atrial pressure than HFpEF-controls both at rest (10 ± 1 vs. 5 ± 1 mmHg) and during exercise (23 ± 2 vs. 14 ± 2 mmHg). Despite higher pulmonary artery wedge pressure (PAWP) at rest in HFpEF-STR than in HFpEF-controls (17 ± 2 vs. 11 ± 2, p = 0.04), PAWP at peak exercise was no more different (28 ± 2 vs. 29 ± 2). Left ventricular transmural pressure and cardiac output (CO) increased less in HFpEF-STR than in HFpEF-controls (interaction p-value < 0.05). This latter was due to lower stroke volume (SV) values both at rest (48 ± 9 vs. 77 ± 9 mL, p < 0.05) and at peak exercise (54 ± 10 vs. 93 ± 10 mL, p < 0.05). Despite these differences, the two groups of patients laid on the same oxygen consumption isophlets because of the increased peripheral oxygen extraction in HFpEF-STR (p < 0.01). We found an inverse relationship between pulmonary vascular resistance and SV, both at rest and at peak exercise (R2 = 0.12 and 0.19, respectively).ConclusionsSevere STR complicating HFpEF impairs SV and CO reserve, leading to pulmonary vascular de-recruitment and relative left heart underfilling, undermining the typical HFpEF pathophysiology.

ObjectivesWe sought to analyze if left ventricular (LV) volumes and ejection fraction (EF) measured by three-dimensional echocardiography (3DE) have incremental prognostic value over measurements obtained from two-dimensional echocardiography (2DE) in patients referred to a high-volume echocardiography laboratory for routine, clinically-indicated studies.MethodsWe measured LV volumes and EF using both 2DE and 3DE in 725 consecutive patients (67% men; 59 ± 18 years) with various clinical indications referred for a routine clinical study.ResultsLV volumes were significantly larger, and EF was lower when measured by 3DE than 2DE. During follow-up (3.6 ± 1.2 years), 111 (15.3%) all-cause deaths and 248 (34.2%) cardiac hospitalizations occurred. Larger LV volumes and lower EF were associated with worse outcome independent of age, creatinine, hemoglobin, atrial fibrillation, and ischemic heart diseases). In stepwise Cox regression analyses, the associations of both death and cardiac hospitalization with clinical data (CD: age, creatinine, hemoglobin, atrial fibrillation, and ischemic heart disease) whose Harrel’s C-index (HC) was 0.775, were augmented more by the LV volumes and EF obtained by 3DE than by 2DE parameters. The association of CD with death was not affected by LV end-diastolic volume (EDV) either measured by 2DE or 3DE. Conversely, it was incremented by 3DE LVEF (HC = 0.84, p < 0.001) more than 2DE LVEF (HC = 0.814, p < 0.001). The association of CD with the composite endpoint (HC = 0.64, p = 0.002) was augmented more by 3DE LV EDV (HC = 0.786, p < 0.001), end-systolic volume (HC = 0.801, p < 0.001), and EF (HC = 0.84, p < 0.001) than by the correspondent 2DE parameters (HC = 0.786, HC = 0.796, and 0.84, all p < 0.001) In addition, partition values for mild, moderate and severe reduction of the LVEF measured by 3DE showed a higher discriminative power than those measured by 2DE for cardiac death (Log-Rank: χ2 = 98.3 vs. χ2 = 77.1; p < 0.001). Finally, LV dilation defined according to the 3DE threshold values showed higher discriminatory power and prognostic value for death than when using 2DE reference values (3DE LVEDV: χ2 = 15.9, p < 0.001 vs. χ2 = 10.8, p = 0.001; 3DE LVESV: χ2 = 24.4, p < 0.001 vs. χ2 = 17.4, p = 0.001).ConclusionIn patients who underwent routine, clinically-indicated echocardiography, 3DE LVEF and ESV showed stronger association with outcome than the corresponding 2DE parameters.

Case Presentation A 47-year-old man was referred to our outpatient clinic for dyspnea and chest pain. His past medical history was remarkable for an admission of acute congestive heart failure, occurred two weeks before presentation. On that occasion, the patient was discharged after a few days of diuretic therapy. Diagnostic Workup at presentation, the patient was symptomatic for dyspnea with signs of systemic congestion. The ECG showed sinus rhythm, inferolateral negative T waves and absent progression of R wave in precordial leads. Transthoracic echocardiography revealed markedly thickened left ventricular (LV) walls (maximum interventricular septum dimension 19 mm) with a granular-sparkling appearance of the myocardium, bi-atrial enlargement, preserved LV ejection fraction, restrictive mitral flow pattern thickened interatrial septum and atrio-ventricular valves. No significant valvular regurgitations were detected. Global LV longitudinal strain was significantly reduced (-9.4%), with relative apical sparing. Given the high suspicion for infiltrative disease we performed further investigations. The cardiac computed tomography (CCT) excluded significant coronary artery disease, but it raised the suspicion of a thrombus at the level of the right atrial appendage, that was confirmed by a transesophageal echocardiography showing a mobile round mass of 14×12 mm. Finally, tissue characterization by cardiac magnetic resonance exhibit a diffuse myocardial delayed enhancement, with a dark blood pool and, an increase in extracellular volume and T1 mapping values (1266.3 ms). Laboratory tests showed increased levels of creatinine, BNP and, lambda light chains. Bone scintigraphy imaging didn't identify any uptake of radiotracers at myocardial level. These findings were suggestive for cardiac light-chain (AL) amyloidosis. Accordingly, a treatment with warfarin, beta-blockers, steroid, and diuretics was initiated. Conclusions cardiac amyloidosis is an infiltrative disease characterized by the deposition of aggregates of amyloid fibrils in the myocardium. Multimodality imaging is pivotal to determine the diagnosis, assess the potential complications, and stratify the patients’ prognosis. Our case demonstrates that cardiac AL amyloidosis is associated with an increased thromboembolic risk, irrespective of the presence of atrial fibrillation. Moreover, although the left atrial appendage is most frequently the site of thrombus formation, it is advised to look for them also in uncommon sites as the right atrial appendage.

Background In patients with paroxysmal atrial fibrillation (AF), left atrial (LA) mechanics has been reported to be important to predict recurrences after cardioversion. However, the potential additive role of right atrial (RA) function in this setting remains to be tested. Accordingly, the aims of our study was to assess the added role of right atrial reservoir longitudinal strain (RARS) for prediction of AF recurrence after electrical cardioversion. Methods we prospectively studied 130 (mean age 69±14, 55% men) consecutive patients with persistent AF who underwent electrical cardioversion, acquired between June 2020 and December 2021. Exclusion criteria were: presence of pacemaker, more than moderate mitral and tricuspid regurgitation, left or right ventricular dysfunction, prior cardiac surgery, and, inadequate acoustic window. LA and RA 2D-speckle-tracking echocardiography analyses were obtained from dedicated, non-foreshortened 4-ch and RV-focused apical 4-ch views respectively, using a dedicated software package (AFI LA, EchoPAC 204, GE Vingmed, Horten, Norway). The primary endpoint was AF recurrence. Results after a follow-up period of 12 months, 60 patients (45%) reached the primary endpoint. The mean left ventricular ejection fraction (LVEF) was 56.5±8%, for all patients. No significant difference in LA (98±31 vs 94±30 mL, p= 0.333) and RA (68±26 vs 65±26 mL, p=0.286) volumes was detected between patients with and without AF recurrence, while left atrial reservoir strain (LARS, 10±6 vs 14±7%, p Conclusions RARS is an independent predictor of the recurrences of AF after electrical cardioversion and provides an incremental prognostic value over LARS. This study highlights the pivotal role of the assessment of bi-atrial remodeling in patients with AF.

Background LV volumes and LVEF measured by 3DE are more accurate and repeatable than those calculated with 2DE. However, the added prognostic value of 3DE LV volumes and EF remains to be clarified. Objectives To analyze if the left ventricular (LV) volumes and ejection fraction (EF) measured by three-dimensional echocardiography (3DE) have an incremental prognostic value over measurements obtained from two-dimensional echocardiography (2DE) in patients referred to a high-volume echocardiography laboratory. Methods We measured LV volumes and EF using both 2DE and 3DE in 725 consecutive patients (67% men; 59±18 years) with various clinical indications referred for a routine clinical study. Results LV volumes were significantly larger, and EF was lower when measured by 3DE than 2DE. During follow-up (3.6±1.2 years), 111 (15.3%) all-cause deaths and 248 (34.2%) cardiac hospitalizations occurred. Larger LV volumes and lower EF were associated with worse otcome independent of age, creatinine, hemoglobin, atrial fibrillation, and ischemic heart diseases). In stepwise Cox regression analyses, the association of both death and cardiac hospitalization with clinical data (CD: age, creatinine, hemoglobin, atrial fibrillation and ischemic heart disease) whose Harrel's C-index (HC) was 0.775, were augmented more by the LV volumes and EF obtained by 3DE than by 2DE parameters. The association of CD with death was not affected by LV end-diastolic volume (EDV) either measured by 2DE or 3DE. Conversely, it was incremented by 3DE LVEF (HC= 0.84, p Conclusions 3DE LVEF and ESV showed stronger association with outcome than 2DE parameters LVEF measured by 3DE had a prognostic discriminatory power than 2D LVEF. Moreover, 3DE LV volumes threshold values for LV dilation had a higher discriminatory power and prognostic value than the corresponding 2DE values reported in current guidelines.

Background in secondary tricuspid regurgitation (STR), the remodeling of the right ventricle (RV) and the right atrium (RA) is associated with different outcomes. However, the potential prognostic role of right RA function in this setting, assessed by 2D-speckle tracking echocardiography (2D-STE), remains to be tested. Accordingly, the aim of our study is to assess the prognostic value of RA 2D-STE in patients with significant (i.e. moderate or severe) STR. Methods we retrospectively studied 227 (mean age 74±14, 40% men, 59% sinus rhythm) consecutive patients with significant STR, acquired between May 2012 and June 2021. RA 2D-STE was obtained from a dedicated, non-foreshortened RV-focused apical 4-ch view, using a dedicated software package (AFI LA, EchoPAC 204, GE Vingmed, Horten, Norway). Among the three longitudinal strain components provided by the software package (reservoir, conduit and, contraction), we focused on RA longitudinal strain during reservoir (RASR). Patients were divided into two groups according to the median value of RARS (12%). A combined endpoint of heart failure hospitalization and all-cause mortality was defined. Results after a median follow-up period of 14 months (IQR, 1-27), 93 patients (41%) reached the combined endpoint. The predictive power of RARS Conclusions in patients with significant STR, RARS is an independent predictor of the combined endpoint of heart failure hospitalization and all-cause mortality and provides incremental prognostic value over RA volume.

Background Echocardiographic surrogates of right ventricle (RV) to pulmonary artery (PA) coupling have been reported to be associated with outcomes in secondary tricuspid regurgitation (STR). However, pulmonary artery systolic pressure (PASP) is difficult to be estimated using echocardiography in patients with severe STR and 3D-derived indexes are loading dependent. Objectives To evaluate the predictive power of a new surrogate of RV-PA coupling obtained using RV volumes measured by three-dimensional echocardiography (3DE), accounting for regurgitant volume of STR. Methods Patients with moderate or severe STR were enrolled. The primary outcome was the composite endpoint of death from any cause and heart failure hospitalization. Results 180 patients were included with a median follow up of 24 months (IQR: 2-48); 72 patients (40%) reached the primary endpoint. Among the tested RV-PA coupling indexes, the ratio between (RV stroke volume [SV]-regurgitant volume)/ RV End-systolic volume (ESV) (i.e. RV forward SV/ESV) showed the highest predictive power of the combined endpoint (AUC 0.85 [IC 95% 0.78-0.93]), with a threshold value of 0.40. It was followed by RV ejection fraction/PASP (AUC 0.75 [IC 95% 0.67-0.84]), and TAPSE/PASP (AUC 0.76 [IC 95% 0.68-0.85]). Severe TR (HR 2.04 [CI 95%: 1.10-3.78], p=0.02), TAPSE/PASP Conclusions RV forward SV/ESV is able to stratify the risk of death and HF hospitalization in patients with STR when added to TR severity, RV ejection fraction and TAPSE/PASP

Background ventricular functional mitral regurgitation (v-FMR) is associated with an increased risk of mortality and hospitalization for heart failure. In this setting, the echocardiographic assessment of v-FMR severity using 2D proximal isovelocity surface area (PISA) yields several limitations, potentially leading to an underestimation of v-FMR severity. An alternative approach is to derive the regurgitant volume (RegVol) and the effective regurgitant orifice area (EROA) using the three-dimensional echocardiography (3DE) to estimate left ventricular volumes (volumetric method, VM). However, a direct comparison of these methods has never been tested. Accordingly, the aims of our study are: i; to compare both 2D PISA measurements of EROA and RegVol with those obtained by VM using 3DE, ii; to test their accuracy using the 3D planimetry of vena contracta area (3D-VCA) of MR jet, as reference. Methods we retrospectively analysed 82 (mean age 75±12, 48% men, 79% sinus rhythm, 85% with ischemic cardiomyopathy, 15% with dilated cardiomyopathy) consecutive patients with v-FMR and reduced left ventricular ejection fraction (LVEF Results average LV end-diastolic and end-systolic volumes, total stroke volume, LVEF and global longitudinal strain were 211±25 mL, 134±17 mL, 73±9 mL, 36±8% and, 9.4±2.7% respectively. Median Ao SV was 50±12 mL. Left atrial volume and left atrial reservoir strain were respectively 99±19 mL and 10±16%. Both EROA and RegVol by VM were larger than EROA (0.17± 0.09 cm2 vs 0.11± 0.01 cm2; p Conclusions in patients with v-FMR, the echocardiographic assessment of EROA and RegVol using the 3DE volumetric method showed larger values compared to the conventional PISA method, and a closer correlation with the 3D VCA. Accordingly, the 3DE VM could improve the accuracy of evaluation of v-FMR severity. Larger studies with longer clinical follow-up are needed to define if it translates into improved risk stratification and may address patients’ management.

Aims A byproduct of left atrial (LA) strain analysis is the automated measurement of LA maximal volume (LAVmax), which may decrease the time of echocardiography reporting, and increase the reproducibility of the LAVmax measurement. However, the automated measurement of LAVmax by two-dimensional speckle-tracking analysis (2DSTE) has never been validated. Accordingly, we sought to (i) assess the feasibility of automated LAVmax measurement by 2DSTE; (ii) compare the automated LAVmax by 2DSTE with conventional two-dimensional (2DE) biplane and three-dimensional echocardiography (3DE) measurements; and (iii) evaluate the accuracy and reproducibility of the three echocardiography techniques. Methods and results LAVmax (34–197 mL) were obtained from 198/210 (feasibility 94%) consecutive patients (median age 67 years, 126 men) by 2DSTE, 2DE, and 3DE. 2DE and 2DSTE measurements resulted in similar LAVmax values [bias = 1.5 mL, limits of agreement (LOA) ± 7.5 mL], and slightly underestimated 3DE LAVmax (biases = −5 mL, LOA ± 17 mL and −6 mL, LOA ± 16 mL, respectively). LAVmax by 2DSTE and 2DE were strongly correlated to those obtained by cardiac magnetic resonance (CMR) (r = 0.946 and r = 0.935, respectively; P Conclusion Automated LAVmax measurement by 2DSTE is highly feasible, highly reproducible, and provided similar values to conventional 2DE calculations in consecutive patients with a wide range of LAVmax.

BackgroundTricuspid annulus (TA) sizing is essential for planning percutaneous or surgical tricuspid procedures. According to current guidelines, TA linear dimension should be assessed using two-dimensional echocardiography (2DE). However, TA is a complex three-dimensional (3D) structure.AimIdentify the reference values for TA geometry and dynamics and its physiological determinants using a commercially available three-dimensional echocardiography (3DE) software package dedicated to the tricuspid valve (4D AutoTVQ, GE).MethodsA total of 254 healthy volunteers (113 men, 47 ± 11 years) were evaluated using 2DE and 3DE. TA 3D area, perimeter, diameters, and sphericity index were assessed at mid-systole, early- and end-diastole. Right atrial (RA) and ventricular (RV) end-diastolic and end-systolic volumes were also measured by 3DE.ResultsThe feasibility of the 3DE analysis of TA was 90%. TA 3D area, perimeter, and diameters were largest at end-diastole and smallest at mid-systole. Reference values of TA at end-diastole were 9.6 ± 2.1 cm2 for the area, 11.2 ± 1.2 cm for perimeter, and 38 ± 4 mm, 31 ± 4 mm, 33 ± 4 mm, and 34 ± 5 mm for major, minor, 4-chamber and 2-chamber diameters, respectively. TA end-diastolic sphericity index was 81 ± 11%. All TA parameters were correlated with body surface area (BSA) (r from 0.42 to 0.58, p < 0.001). TA 3D area and 4-chamber diameter were significantly larger in men than in women, independent of BSA (p < 0.0001). There was no significant relationship between TA metrics with age, except for the TA minor diameter (r = −0.17, p < 0.05). When measured by 2DE in 4-chamber (29 ± 5 mm) and RV-focused (30 ± 5 mm) views, both TA diameters resulted significantly smaller than the 4-chamber (33 ± 4 mm; p < 0.0001), and the major TA diameters (38 ± 4 mm; p < 0.0001) measured by 3DE. At multivariable linear regression analysis, RA maximal volume was independently associated with both TA 3D area at mid-systole (R2 = 0.511, p < 0.0001) and end-diastole (R2 = 0.506, p < 0.0001), whereas BSA (R2 = 0.526, p < 0.0001) was associated only to mid-systolic TA 3D area.ConclusionsReference values for TA metrics should be sex-specific and indexed to BSA. 2DE underestimates actual 3DE TA dimensions. RA maximum volume was the only independent echocardiographic parameter associated with TA 3D area in healthy subjects.

Functional or secondary tricuspid regurgitation (FTR) is a progressive disease with a significant negative impact on patient morbidity and mortality. Recently, atrial fibrillation (AF) has been recognized as a cause of FTR (with/without coexisting functional mitral regurgitation) by promoting right atrial (RA) remodeling and secondary tricuspid valve (TV) annulus dilation, even in the absence of right ventricular (RV) dilation or dysfunction. This distinct form of FTR has been called “atriogenic” or “atrial”. Recent evidence suggests that the RA is an important player in FTR pathophysiology not only for patients with AF, but also for those in sinus rhythm. Preliminary reports on atrial FTR show that cardioversion with documented maintenance of sinus rhythm promotes TV annulus and RA reverse remodeling and may significantly reduce FTR severity at follow-up. Large-scale studies on the prognostic benefits of rhythm vs rate-control strategy in atrial FTR patients are needed to substantiate specific guidelines indications for this subset of patients.

This editorial refers to 'Tricuspid and mitral remodelling in atrial fibrillation: a three-dimensional echocardiographic study' by Ortiz-Leon X.A. et al., https://doi.org/ 10.1093/ehjci/jeac045.

Functional tricuspid regurgitation (FTR) is a strong and independent predictor of patient morbidity and mortality if left untreated. The development of transcatheter procedures to either repair or replace the tricuspid valve (TV) has fueled the interest in the pathophysiology, severity assessment, and clinical consequences of FTR. FTR has been considered to be secondary to tricuspid annulus (TA) dilation and leaflet tethering, associated to right ventricular (RV) dilation and/or dysfunction (the “classical”, ventricular form of FTR, V-FTR) for a long time. Atrial FTR (A-FTR) has recently emerged as a distinct pathophysiological entity. A-FTR typically occurs in patients with persistent/permanent atrial fibrillation, in whom an imbalance between the TA and leaflet areas results in leaflets malcoaptation, associated with the dilation and loss of the sphincter-like function of the TA, due to right atrium enlargement and dysfunction. According to its distinct pathophysiology, A-FTR poses different needs of clinical management, and the various interventional treatment options will likely have different outcomes than in V-FTR patients. This review aims to provide an insight into the anatomy of the TV, and the distinct pathophysiology of A-FTR, which are key concepts to understanding the objectives of therapy, the choice of transcatheter TV interventions, and to properly use pre-, intra-, and post-procedural imaging.

We present the case of a 73-year-old patient with a recent diagnosis of hypertrophic cardiomyopathy (HCM). He was asymptomatic and has no family history of sudden cardiac death (SCD), syncope or ventricular arrhythmias. An echocardiogram performed at the moment of diagnosis (2020), showed left ventricular (LV) asymmetric apical hypertrophy with maximal wall thickness of 21 mm. Cardiac magnetic resonance (CMR) confirmed LV apical hypertrophy with mid-ventricular obliteration, and late gadolinium enhancement in the apical segments, without wall motion abnormalities present at rest. According to 2014 ESC guidelines, his calculated risk score for sudden cardiac death was low (1.23% at 5 years). On 2021, a comprehensive transthoracic echocardiographic examination including advanced techniques (three-dimensional echo-3DE-, and two-dimensional speckle-tracking-2DSTE) was done as part of his routine follow-up in our cardiomyopathy outpatient clinic. The echo study showed an asymmetric pattern of LV hypertrophy with a maximal wall thickness of 21 mm at the level of the anterolateral apical segment, normal LV volumes (end-diastolic volume 55 mL/m2) and ejection fraction (69%) by 3DE. LV longitudinal strain analysis by 2DSTE showed impaired LV myocardial deformation mainly at the apical LV segments (GLS = −13.6%). There was evidence of dynamic intracavitary obstruction (maximal gradient 32 mmHg at rest and raised to 52 mmHg during Valsalva manoeuvre). 3DE views of the LV (both multi-slice display and 3D rendered image) allowed to avoid foreshortening of the LV apical views, and to appreciate the actual wall motion at the real LV apex. They revealed a LV apical aneurysm which was not detected in the conventional LV-focused apical 2D views (Figure 1A and B). Apical hypertrophic cardiomyopathy (ApHCM) is a variant of HCM that is characteristic of focal thickening of the LV apical myocardium and was reported to have a more benign course than other non-apical forms. However, the presence of LV aneurysm in ApHCM patients is associated with an increased risk for ventricular arrhythmias, sudden cardiac death and thromboembolism. Accordingly, the detection of apical LV aneurysms has significant impact on patient management. Guidelines recommend the use of contrast echocardiography or CMR when the apical region of the LV is suboptimally visualized by conventional 2D echocardiography. However, contrast echocardiography may still be affected by apical foreshortening resulting in suboptimal accuracy, as it is a 2D technique. On the other end, CMR may be contraindicated or not widely available for routine yearly follow-up for all HCM patients requiring regular imaging follow-up. Our clinical case emphasizes the added value of 3DE to increase the sensitivity of transthoracic echocardiography in detecting apical LV aneurysms in patients with apical HCM with important clinical implications for the management of the patient. 813 Figure 1(A) 2D 4chamber-view showing maximal wall thickness in the apical segments (21 mm) with apical obliteration. At a first evaluation, apical aneurism is not easily detected. (B) 4D rendering of the apex showing the apical aneurism.

Aims Atrial functional tricuspid regurgitation (A-FTR) has emerged as a newly recognized phenotype of functional tricuspid regurgitation (FTR), occurring in patients with atrial fibrillation and right atrial (RA) dilation but normal right ventricular (RV) size and function. Its prevalence, echocardiographic features, and prognosis have not yet clarified since most evidence to date has included indiscriminately FTR patients with A-FTR and ventricular form (V-FTR). Aim of this study was to investigate the differences between these two phenotypes of FTR in terms of clinical correlates, echocardiographic aspects, and prognosis. Methods and results A total of 180 consecutive patients with moderate to severe FTR referred for echocardiography in two Italian centres were retrospectively enrolled. A-FTR was defined as: (1) longstanding atrial fibrillation; (2) PASP 60% (complete according to the ACC guidelines); and (4) no significant left side valve disease. 3D TTE was used for the quantitative assessment of TR and chamber sizing and function. The composite endpoint of death for any cause and heart failure (HF) hospitalization was used as primary outcome of this analysis; secondary endpoint was HF-hospitalization. Patients with A-FTR were 30% of the population; they were older than those one with V-FTR; with higher systolic blood pressure and less advanced symptoms. Chronic obstructive pulmonary disease was more prevalent in V-FTR. Patients with V-FTR had larger 3D-derived right ventricle (RV) volumes, both diastolic and systolic, while right ventricle ejection fraction (RVEF) was similar. RV functional parameters as TAPSE, RVFWLS, and RVGLS were significantly lower in the V-FTR patients as well as all the parameters of RV-pulmonary arterial (PA) coupling. After a median follow-up of 24 months (IQR: 2–48), 72 patients (40%) reached the primary endpoint and 64 (36%) hospitalized for HF. The rate of composite endpoint tended to be lower in A-FTR than in V-FTR (29% vs. 44%, P-value: 0.1); the rate of hospitalization for HF was higher in V-FTR patients (22% vs. 41%, P-value: 0.04). Correlates of combined endpoint in both groups were: functional class of dyspnoea (NYHA class III–IV vs. I–II), severe TR grade (HR in V-FTR: 2.88 [1.63–5.06], P Conclusions Patients having A-FTR have an incidence of combined endpoint slightly different, without reaching a statistically significant difference, thus remarking the fact that A-FTR could not be considered ‘more benign’ and should therefore be targeted. Prognostic predictors are different between A-.FTR and V-FTR patients.

A 32-year-old female was referred to our outpatient clinic for exertional dyspnoea that had worsened in the preceding months. She had a history of mitral and aortic valve replacement with bileaflet mechanical prosthesis (St. Jude Master n. 25 and Medtronic Open Pivot n. 16, respectively) for rheumatic heart disease. A recent echocardiography showed borderline-high trans-aortic gradients (mean 26 mmHg, peak 42 mmHg). Transthoracic echocardiography revealed abnormal aortic transprosthetic flow (peak velocity 442 cm/s, mean gradient 48 mmHg). Continuous Wave Doppler signal was rounded with a long acceleration time (108 ms). Effective orifice area (EOA) was 0.8 cmq (index EOA 0.48 cmq/mq) and Doppler Velocity Index 0.28. Further investigations revealed no signs of infections but suboptimal anticoagulation (INR 2.5). Transesophageal 3D echocardiography was suggestive for hypomobility of the prosthetic leaflets and the presence of an isoechoic mass encircling the ventricular side of the aortic prosthesis compatible with pannus overgrowth. Cardiac CT confirmed the presence of a symmetrical reduction in the systolic opening of both leaflets. The patient underwent a redo of aortic valve replacement that confirmed the presence of an asymmetric subprosthetic pannus overgrowing on the previously implanted surgical pledgets. After pannus debritment a St. Jude Regent n. 21 was implanted. The patient experienced complete symptomatic resolution. We presented the case of a prosthetic aortic valve dysfunction due to a combination of patient-prosthesis mismatch and pannus overgrowth. In our patient, as assessed in the old echocardiographic examinations, the presence of mildly elevated transprosthetic gradients was suggestive for prosthesis undersizing related to body surface area. In this scenario, subvalvular pannus formation caused significant changes in prosthetic valve transvalvular flow dynamic leading to prosthesis dysfunction. This case emphasises the crucial role of echocardiographic follow up in detection of causes of prosthetic heart valve dysfunction and how optimal valve sizing is paramount in aortic valve replacement.

Aims We present the case of a 25 years-old patient, presented to the Emergency Department for chest pain and epigastralgia complicated by vomiting. Symptoms started about 30 h before, afterwards an effort. The patient did not have any known cardiovascular risk factors (except for sporadic consumption of cannabis) and family medical history was negative for premature cardiovascular disease or sudden cardiac death. His past medical history was unremarkable. Methods and results Clinical examination was normal. ECG was suggestive for subacute anterior ST-elevation myocardial infarction (QS in V1–V4 leads with ST segment elevation and biphasic T-waves in V4–V6) and was accompanied by significant elevation of myocardial necrosis biomarkers (hsTnT 3416 ng/l, n.v. Conclusions Spontaneous coronary artery dissection (SCAD) is an underdiagnosed and frequent cause of acute coronary syndrome (ACS) in young-to-middle aged patients, particularly women; therefore, even in young people, a chest pain episode suggestive for an ischaemic cause should never be underestimated. Cardiac magnetic resonance is the most accurate method to evaluate the sequelae of myocardial infarction (including LV size and function, presence of fatty metaplasia, extent and transmurality of ischaemic scar, presence of thrombi), to aid in differential diagnosis and to define prognosis and guide the therapeutic management.

Aims A by-product of left atrial (LA) strain analysis is the automated measurement of LA maximal volume (LAVmax), which may decrease the time of echocardiography reporting, and increase the reproducibility of the LAVmax measurement. However, the automated measurement of LAVmax by two-dimensional speckle-tracking analysis (2DSTE) has never been validated. Accordingly, we sought to: (i) assess the feasibility of automated LAVmax measurement by 2DSTE; (ii) compare the automated LAVmax by 2DSTE with conventional two-dimensional (2DE) biplane and three-dimensional echocardiography (3DE) measurements; and (iii) evaluate the accuracy and reproducibility of the three echocardiography techniques. Methods and results LAVmax (34–197 ml) were obtained from 198/210 (feasibility 94%) consecutive patients with various cardiac diseases (median age 67 years, 126 men) by 2DSTE, 2DE, and 3DE. 2DE and 2DSTE measurements resulted in similar LAVmax values (bias = 1.5 ml, limits of agreement, LOA ± 7.5 ml), and slightly underestimated 3DE LAVmax (biases = −5 ml, LOA ± 17 ml, and −6 ml, LOA ± 16 ml, respectively). LAVmax by 2DSTE and 2DE were strongly correlated to those obtained by cardiac magnetic resonance (CMR) (r = 0.946, and r = 0.935, respectively; P < 0.001). However, LAVmax obtained by 2DSTE (bias = −9.5 ml, LOA ± 16 ml) and 2DE (bias = −8 ml, LOA ± 17 ml) were significantly smaller than those measured by CMR. Conversely, 3DE LAVmax were similar to CMR (bias = −2 ml, LOA ± 10 ml). Excellent intra- and inter-observer intraclass correlations were found for 3DE (0.995 and 0.995), 2DE (0.990 and 0.988), and 2DSTE (0.990 and 0.989). Conclusions Automated LAVmax measurement by 2DSTE is highly feasible, highly reproducible, and provided similar values to conventional 2DE calculations in consecutive patients with a wide range of LAVmax.

Aims Atrial and ventricular functional tricuspid regurgitation (A-FTR and V-FTR) have recently emerged as different phenotypes of FTR. Given the difference in mechanisms that are postulated to be underlying these two entities, a different remodelling of tricuspid valve (TV) apparatus can occur and therefore also a specific quantitative approach could be deemed. Moreover, considered the known limitation of the two-dimensional flow convergence method (2D-PISA) for quantifying FTR in advanced valve apparatus remodelling with irregular effective valve orifice (ERO) morphology, it would be expected that also the parameters of severity of FTR can be different in these two types of FTR. The aim of this study was to investigate the TV apparatus remodelling in the two different phenotypes of FTR: ventricular (V-FTR) and atrial (A-FTR) and the role of echocardiographic parameters of TV remodelling and TR severity to predict clinical outcomes. Methods and results The present retrospective study included consecutive patients with moderate to severe functional tricuspid regurgitation (FTR) referred for echocardiography in two Italian centres. The composite endpoint of death for any cause and heart failure (HF) hospitalization was used as primary outcome of this analysis. According to more recent guidelines, patients were considered having A-FTR if having history of long-standing atrial fibrillation, without history of pulmonary hypertension and left side heart disease. A total of 180 patients were included. Despite the right atrial volume (RAV) was not different in the two groups, in A-FTR tethering height was significantly lower (11.7 ± 4.8 mm vs. 15.0 ± 5.5 in V-FTR. P Conclusions Different TV remodelling occurs in patients with A- and V-FTR, having the second more pronounce tethering of TV leaflets; the prognostic role of quantitative parameters of FTR in these two groups is different, thus reaffirming: (1) the limitation of PISA method without correction in case of more pronounced tenting of leaflets; (2) the difference in underlying pathogenic mechanisms; and (3) the needing for a more specific diagnostic approach and prognostic stratification in these two FTR phenotypes.

Aims Non-invasive parameters used to assess right ventricular (RV) function, i.e. tricuspid annular plane systolic excursion (TAPSE), RV fractional area change (FAC), RV ejection fraction (RVEF), and RV free-wall longitudinal strain (RVFWLS) have shown their prognostic implications. However, since they are extremely load dependent, they do not provide an accurate representation of the RV intrinsic performance. On the other end, invasive indices of RV-arterial coupling (RVAC) derived from pressure–volume loops are not routinely performed, rising the urgency for more feasible, and reliable non-invasive estimates of RVAC. To (i) evaluate the prognostic value of echocardiography-derived RVAC surrogates: RVEF/sPAP, RVFWLS/sPAP, TAPSE/sPAP, FAC/sPAP, and RV stroke volume/end-systolic volume (SV/ESV); (ii) identify the cut-off values associated to all-cause mortality; and (iii) compare their prognostic value with that of classical parameters of RV function. Methods and results We prospectively enrolled 366 patients with various cardiac diseases, undergoing clinically indicated comprehensive two- and three-dimensional echocardiography. During a mean follow-up of 7.6 ± 1 years, 80 (21.9%) patients died. At univariable Cox regression, most of the echocardiographic parameters were related to all-cause mortality. The echocardiographic parameters with significance at univariable analysis (P Conclusions RVAC surrogates provide incremental prognostic value compared to standard RV functional measurements. RVEF/sPAP, with a cut-off value of 1.5, was the best parameter for risk stratification, and was independently related to all-cause mortality.

Aims Atrial functional tricuspid regurgitation (A-FTR) is a recently defined phenotype of FTR associated with persistent/permanent atrial fibrillation. Differently from the classical ventricular form of FTR (V-FTR), patients with A-FTR might present with severely dilated right atrium (RA) and tricuspid annulus (TA), and with preserved right ventricular (RV) size and systolic function. However, the geometry and function of the RV, RA, and TA in patients with A-FTR and V-FTR remain to be systematically evaluated. Accordingly, we sought to: (i) study the geometry and function of the RV, RA, and TA in A-FTR by two- and three-dimensional transthoracic echocardiography and (ii) compare them with those found in V-FTR. Methods and results We prospectively analysed 113 (44 men, age 68 ± 18 years) FTR patients (A-FTR = 55 and V-FTR = 58) that were compared to two groups of age- and sex-matched controls to develop the respective Z-scores. Severity of FTR was similar in A-FTR and V-FTR patients. Z-scores of RV size were significantly larger, and those of RV function were significantly lower in V-FTR than in A-FTR (P 2), with similar RA maximal volume (RAVmax) between A-FTR and V-FTR (P = 0.2). Whereas, the RA minimal volumes (RAVmin) were significantly larger in A-FTR than in V-FTR (P = 0.001). Conclusions Despite similar degrees of FTR, and RAVmax size, A-FTR patients show a larger RAVmin, and smaller TA areas than V-FTR patients. Conversely, V-FTR patients show dilated, more elliptic, and dysfunctional RV than A-FTR patients.

Neprilisin and angiotensin receptor inhibition (Sacubitril/Valsartan, i.e. ARNI) is recommended in heart failure guidelines for patients in NYHA class II-III with reduced left ventricular ejection fraction (LVEF). ARNI increase survival and quality of life; due to their hemodynamic effects, ARNI could also affect exercise tolerance. We studied the effects of ARNI on cardiopulmonary test (CPET) after six months of treatment in 35 patients [67 ± 11 years; LVEF 31 ± 6%; NT-proBNP 1822 ± 1651 pg/ml; ICD/CRT since at least 6 months in 26/35], treated with increasing doses of Sacubitril/Valsartan up to 318 ± 36 mg/die. In addition, levels of NT-proBNP, renal function, electrolytes, and echocardiocolorDoppler were assessed in the same time periods. No variations of renal function and/or potassium levels were observed; NT-proBNP decreased. Most CPET variables were improved by ARNI (p

Introduction: The tricuspid valve (TV) and the right heart chambers are complex three-dimensional structures that are difficult to assess using tomographic imaging techniques. The progressive aging of the general population and the advancements in treating left-sided heart diseases by transcatheter procedures have contributed to the tricuspid regurgitation (TR) becoming a major public health problem associated with progression to refractory heart failure and poor outcome. Recent advances in multimodality cardiac imaging allow a better understanding of the pathophysiology of TR that may translate in better management of patients. Areas covered: Three-dimensional echocardiography, cardiac magnetic resonance, and computed tomography provide complementary information to i. assess the TV complex; ii. identify the etiology and the mechanisms of TR; iii. evaluate its severity and hemodynamic consequences; iv. explore the remodeling of the right heart chambers; and v. properly plan, guide, and monitor the transcatheter interventions aimed to reduce the severity of TR. Expert opinion: We need thorough understanding of both the TV and the right heart chamber geometry and function to understand the pathophysiology of TR. The integrated use of multimodality cardiac imaging is pivotal to assess patients with TR and to identify tailored and timely treatment of TR in properly selected patients.

Background: Atrial fibrillation (AF) itself may lead to functional tricuspid regurgitation (FTR) through tricuspid annulus (TA) dilation. However, the pathophysiological determinants of TA enlargement in AF patients remain to be clarified. The objectives of this study were (1) to compare the TA size and function in AF patients versus healthy subjects; (2) to identify the determinants of TA remodeling in patients with AF and FTR; and (3) to assess the relationships among right heart structures and severity of FTR in AF patients. Methods: Eighty-three consecutive patients with long-term persistent AF and FTR (61 ± 9.9 years, 67% women) were prospectively enrolled and compared with 83 sex and body surface area–matched healthy subjects. Heart chamber size and function and TA geometry were analyzed using three-dimensional echocardiography. Results: Among AF patients, 33%, 34%, and 33% had mild, moderate, and severe FTR, respectively. Right atrial (RA) dilation was detected in 93% of AF patients, while only 27% and 12% of them showed dilated or dysfunctional right ventricle (RV), respectively. End-diastolic TA area had the strongest correlation with the minimum volume of the RA (RAVmin r = 0.6981, P

Doppler echocardiography assessment of left ventricular (LV) filling pressures at rest and during exercise is the most widely used imaging technique to assess LV diastolic function in clinical practice. However, a sizable number of patients evaluated for suspected LV diastolic function show an inconsistency between the various parameters included in the flowchart recommended by current Doppler echocardiography guidelines and results in an undetermined LV diastolic function. Current three-dimensional echocardiography technology allows obtaining accurate measurements of the left atrial volumes and functions that have been shown to improve the diagnostic accuracy and prognostic value of the algorithms recommended for assessing both LV diastolic dysfunction and heart failure with preserved ejection fraction. Moreover, current software packages used to quantify LV size and function provide also volume-time curves showing the dynamic LV volume change throughout the cardiac cycle. Examining the diastolic part of these curves allows the measurement of several indices of LV filling that have been reported to be useful to differentiate patients with normal LV diastolic function from patients with different degrees of diastolic dysfunction. Finally, several software packages allow to obtain also myocardial deformation parameters from the three-dimensional datasets of both the left atrium and the LV providing additional functional parameters that may be useful to improve the diagnostic yield of three-dimensional echocardiography for the LV diastolic dysfunction. This review summarizes the current applications of three-dimensional echocardiography to assess LV diastolic function.

The continuous search for more efficient drives, recently motivated also by environmental issues and innovative electro-mechanical applications, has led to a renovated interest in Continuously Variable Transmissions (CVTs). Several novel geometries of traction drives have been proposed in the recent past, to improve the performance sometimes with a look at miniaturization. A modified version of the well-known Kopp variator has recently been engineered under the name of NuVinci drive. NuVinci was designed for being installed on bicycles but with the promise to be suitable also for a wide range of other applications. In this paper, we present a mathematical model of this device, developed to study its performance, compare different relevant variants and improve the design. The performances are discussed in terms of traction capabilities and efficiency. It is shown how a slight modification of the geometry may lead to an evident change of the performance indicators, in particular the efficiency.

This paper proposes a new topology of the Common-Rail injection system. This injection system has been the milestone for the success of the diesel engines in the automotive market for over three decades. The innovative aspect of the new topology consists in the introduction of a Continuously Variable Transmission (CVT) between the engine and the high-pressure pump. This technical solution aims at reducing the speed of the high-pressure pump and, consequently, the energy consumption of the system. Moreover, a control strategy is designed to regulate the common-rail pressure by adjusting the CVT ratio and the Fuel Metering Unit outflow. Simulation results are encouraging and promising for future developments of the proposed approach.

This paper proposes the experimental proof of concept of a new topology of the Common-Rail injection system for diesel engines. The main difference with respect to the traditional Common-Rail system consists in the introduction of a Continuously Variable Transmission (CVT) between the engine and the high-pressure pump. This approach helps reducing the high-pressure pump speed and, consequently, the cuts energy consumption of the system. The proof of concept is designed by adopting a CVT available on the market. The experimental results are encouraging and promising for future developments of the proposed approach.

In this paper, a control strategy for energy management of a parallel hybrid electric UAV (Unmanned Air Vehicle) powertrain is presented. A Simulink-based model of the system is first presented, consisting of an internal combustion engine, a gearbox (which includes a planetary gear and a continuously variable transmission), an electric motor (which can also work as a generator), an electric drive (Inveter) and a Li-Po battery pack. The proposed control strategy consists of a quasi-real-time iterative algorithm based on Dynamic Programming, which allows to optimize power management and torque-split of the powertrain with final state constraints on state variable. Aim of the study is to investigate new flight capabilities that derive from the use of a hybrid architecture, e.g., silent mode using only electric motor (useful for military and civil purpose), and the capacity of reducing fuel consumption. Simulation studies are performed, based on data of an existing UAV and a real flight mission.

In this paper, we present a diesel engine common-rail pressure controller using a Model Reference Adaptive Control (MRAC) approach. The proposed control strategy is designed using the only common rail pressure differential equation and considering all the measurable system parameter variation (e.g the high pressure pump speed). The resulting control strategy looks simple and allows a fast and precise regulation of the common-rail pressure. The tracking performances are compared with those obtained using a standard PID controller that represents the state of art in commercial applications.

In this paper, we present the model in steady state conditions of a planetary traction drive continuously variable transmission (CVT). The model provides the efficiency formulation of the CVT as a function of the geometry, and the operative point considering slip and spin losses in the points of contact. The physical behaviour has been studied using the results from the EHL theory. The simulation results of this model show good efficiency performances and a large reduction ratio range.

The synthesis of carbon nanofibers was carried out by catalytic decomposition of ethylene in presence of hydrogen. Bimetallic catalysts, e.g. Fe–Cu or Ni–Cu, were synthesized by coprecipitation, reduction–precipitation and reverse microemulsion techniques and were proven to have a strong influence on the morphology of the nanofibers. The best results in terms of synthesis homogeneity were obtained by supporting the bimetallic catalyst on a high surface area silica support by the “incipient wetness” method. The hydrogen storage capacity of carbon nanofibers was tested in a custom made Sievert apparatus operating up to 160 bar and 450 °C. Several “in situ” activation procedures were experimented, however according to our data carbon nanofibers do not seem a suitable candidate for hydrogen storage. With the purpose of promoting a “spillover” function, 2 wt.% Pd-doped nanofibers were prepared. After loading at 77 bar, a hydrogen storage of 1.38 ± 0.30 wt.% was measured at room temperature.

Alumina-copper oxide supports can be obtained by cogelation yielding uniformly sized spheres with high surface areas and unimodal mesoporosity, that can be employed as supports for Pd catalysts obtained by impregnation. These are characterized by SEM, XRD, BET, H2 chemisorption and TPR, and can be successfully used in the hydrogenation of nitrate (nitrite) in water with minor ammonia formation.

Some aspects of the industrial development of copper-on-alumina catalytic materials for the combined removal of SO2 (DeSOx and NOx (DeNOx) from flue gas of power plants are discussed. Applications of these catalytic materials for the recovery of sulfuric acid from diluted aqueous solutions of ammonium sulfate are also outlined. In particular, the following specific topics are analyzed: (i) the relationship between textural and reactivity properties. (ii) the problem of the design of samples with improved DeSOx properties in relation to the stability of the samples over extended operations, and (iii) the optimization of the regeneration characteristics of the samples. Details on the flow sheet of the technology are also given.

The behavior of Cu or Sn promoted palladium catalysts supported on zirconia and titania for the hydrogenation of nitrate in drinking water is discussed. Catalysts are prepared either as powders (microspheres) or in the form of membranes deposited on commercial alumina tubes. The performance of the former in terms of activity and selectivity towards the formation of nitrogen in a batch reactor is presented as a function of the preparation procedure, the type of precursor, the Pd/Cu ratio and the type of promoter. The use of catalysts under diffusion controlled conditions allows to reduce significantly the amount of ammonia formed while retaining a high catalytic activity. Membrane catalysts are prepared by sol–gel and characterized by SEM, EDS and hydrogen permeability tests. Their reactivity is studied either in a recirculation reactor or in a continuous flow reactor and the effect of the initial pH, the residence time and the internal hydrogen pressure are reported.

The catalytic behavior and some aspects of the development of novel catalysts for N2O decomposition (rhodium-on-zirconia based catalysts) or selective reduction with propane (Fe/ZSM-5 type catalysts) in the presence of the typical gas phase components of industrial emissions containing N2O in concentrations below 0.1% are discussed. In particular: (i) the possibility to improve the catalytic reactivity of rhodium-on-zirconia based catalysts by modification of the zirconia support with lanthanide ions or other dopants; (ii) the stability of the catalytic behavior of these samples in the presence or absence of SO2; and (iii) some characteristics and the stability behavior of Fe/ZSM-5 catalysts in the presence of SO2 for the reduction of N2O with propane/O2 are reported. The catalytic technologies of decomposition and selective reduction of N2O are compared in terms of economics of the processes and type of emissions for which they are preferably suited.

Sulfated zirconia spheres and microspheres with variable, though strictly controlled, diameters up to several millimeters have been prepared by a new sol gel procedure. The spheres have been also promoted with 1% Pt and have been characterized after calcination at 550° and 600 °C. The Pt modified catalysts are very active and stable in the isomerization of n-butane

Publisher Summary The gel-supported precipitation (GSP) method is a versatile technique to prepare pure and mixed oxides to be used as supports or catalysts in various applications ranging from fluid bed to mobile bed to fixed bed reactors. The characteristics of the samples are analogous to those obtained by the xerogel method using alkoxide precursors in terms of purity, homogeneous dispersion of the components, and the textural and thermal resistance properties. The GSP method, however, has the advantage of allowing the direct synthesis of spheres or microspheres from about 20 μm up to about 3 mm and the synthesis of spherical pellets with shape and mechanical strength characteristics suitable for applications in reactors with solid transport. Furthermore, the method is tailored to avoid the use of expensive raw materials such as alkoxides.

A series of gold(III) complexes of the type [AuCl3(L)] has been prepared and characterised (L = oxazole, benzoxazole, thiazole, their benzo and methyl-substituted derivatives, or 2-methylbenzoselenazole). The five-membered N,O- N,S- and N,Se-heterocyclic bases are all bound to AuIII through nitrogen. The kinetics of the displacement of L by chloride to give [AuCl4]– has been studied in methanol–water (95:5, v/v) at 25.0°C and I= 0.20 mol dm–3(LiClO4). The equilibrium constants for the reversible processes have also been determined. The reactions of the corresponding pyridine, 4-chloro-, 4-cyano- and 2,6-bis(chloromethyl)-pyridine complexes have also been reexamined under the same conditions. The equilibrium constants, K2, depend upon the basicity of the nitrogen in the ligands and points for all ligands, irrespective of ring size and composition, lie roughly on the same log K2versus pKa curve. There is no significant systematic steric effect on the equilibrium constants of the sort found for the more basic methyl pyridines. The complexes of the five-membered heterocyclic ligands are approximately ten times less reactive than those of the six-membered N-heterocycles of comparable basicity and exhibit steric retardation from ortho-methyl substituents. The nucleophilicities of these ligands have been calculated and five-membered N,O- and N,S-heterocycles are considerably less reactive than six-membered N-heterocycles of similar basicity.