The data project: a shared approach between stakeholders of the healthcare system in definition of a therapeutic algorithm for inflammatory arthritis

Rheumatic musculoskeletal diseases or RMD [rheumatoid arthritis (RA) and spondyloarthritis (SpA)] are systemic inflammatory diseases for which there are no biomarkers capable of predicting treatments with a higher likelihood of response in naive patients. In addition, the expiration of the anti-TNF blocking drugs' patents has resulted in the availability of anti-TNF biosimilar drugs with the same efficacy and safety than originators but at significantly reduced prices. To guarantee a personalized therapeutic approach to RMD treatment, a board of rheumatologists and stakeholders from the Campania region, Italy, developed a clinically applicable arthritis therapeutic algorithm to guide rheumatologists (DATA project). The general methodology relied on a Delphi technique forecast to produce a set of statements that summarized the experts' consensus. Selected clinical scenarios were discussed in light of the available evidence, and there were two rounds of voting on the therapeutic approaches. Separate discussions were held regarding rheumatoid arthritis, psoriatic arthritis, and ankylosing spondylitis. The decision-making factors for each disease were clinical presentation, demographics, and comorbidities. In this paper, we describe a virtuous process between rheumatologists and healthcare system stakeholders that resulted in the development of a shared therapeutic algorithm for RMD patients naive to bDMARDs.

A platform for real-3d visualization and planning of left atrial appendage occlusion through mixed reality

Funding Acknowledgements

Type of funding sources: None.

Background

In left atrial appendage occlusion (LAAO), pre-procedural computed tomography (CT) is pivotal to describe the complex and highly variable LAA anatomy and to guide the operator in accurate planning of the intervention. Multiplanar reconstruction and 3D rendering are used for the navigation and analysis of the 3D datasets but they share some limitations that are due to the use of 2D screens; Mixed Reality (MxR) technology aims at overcoming such limitations by allowing for real-3D visualizations with holographic replicas of anatomical models while preserving a sense of presence within the true physical environment by the operator.

Purpose

To develop and test a MxR platform that provides a more intuitive and informative tool for the morphological analysis during the planning phase of LAAO.

Methods

Patients (n = 4) were randomly selected among those referred for a CT scan prior to transcatheter aortic valve replacement, each one characterized by a specific LAA morphology (cauliflower, bilobular, chicken wing, wind-sock). CT scans were performed in diastole at 75% of the R-R interval on a 64-slice scanner, with in-plane resolution 0.38-0.64 mm and slice thickness 0.62 mm. Firstly, the acquisition was cropped to contain the left atrium, the circumflex artery, the left upper pulmonary ridge. Subsequently, an isosurface with high coincidence between the blood cavity border and the endocardium was identified by the user and processed using a marching cube algorithm to obtain the 3D model. Finally, the 3D model was optimized for a MxR platform that allows for moving, zooming and cutting the model, measuring the main LAA linear dimensions and simulating the implant of a virtual replica of a transcatheter occluder.

Results

 

The workflow was successfully applied for all the patients independently from the morphology. All the models were successfully uploaded in the MxR platform (Fig 1.a) and for all the patients the morphological analysis was performed (Fig 1.b) in less than 10 minutes.

The four different morphologies of the LAA were correctly identified allowing a very detailed holographic modeling of the structure, including the neck, the landing zone, the curvature and the position and size of lobes.

For both the identified ostium and landing planes, using a dedicated measuring tool (Fig. 1.c), the operator measured the minimum and maximum diameters, which were later used to define the size of the occluder device to be used in the virtual implant simulation (Fig. 1.d).

Conclusions

The tested MxR platform suggested the potential to overcome the limits of the standard technologies in planning of LAAO thanks to the real-3D perception, potentially leading to a more accurate and faster planning phase. Furthermore, the use of MxR technology may enhance the ability to predict the optimal device size and position within the anatomy to obtain LAA complete sealing.

Abstract Figure.

Feasibility and accuracy of the automated software for dynamic quantification of left ventricular and atrial volumes and function in a large unselected population

Funding Acknowledgements

Type of funding sources: None.

Objective. Preliminary studies showed the accuracy of machine learning based automated dynamic quantification of left ventricular (LV) and left atrial (LA) volumes. We aimed to evaluate the feasibility and accuracy of machine learning based automated dynamic quantification of LV and LA volumes in an unselected population.

Methods. We enrolled 600 unselected patients (12% in atrial fibrillation) clinically referred for transthoracic echocardiography (2DTTE), who also underwent 3D echocardiography (3DE) imaging. LV ejection fraction (EF), LV and LA volumes were obtained from 2D images; 3D images were analysed using Dynamic Heart Model (DHM) software (Philips) resulting in LV and LA volume-time curves. A subgroup of 140 patients underwent also cardiac magnetic resonance (CMR) imaging. Average time of analysis, feasibility, and image quality were recorded and results were compared between 2DTTE, DHM and CMR.

Results. The use of DHM was feasible in 522/600 cases (87%). When feasible, the boundary position was considered accurate in 335/522 patients (64%), while major (n = 38) or minor (n = 149) borders corrections were needed. The overall time required for DHM datasets was approximately 40 seconds, resulting in physiologically appearing LV and LA volume–time curves in all cases. As expected, DHM LV volumes were larger than 2D ones (end-diastolic volume: 173 ± 64 vs 142 ± 58 mL, respectively), while no differences were found for LV EF and LA volumes (EF: 55%±12 vs 56%±14; LA volume 89 ± 36 vs 89 ± 38 mL, respectively). The comparison between DHM and CMR values showed a high correlation for LV volumes (r = 0.70 and r = 0.82, p < 0.001 for end-diastolic and end-systolic volume, respectively) and an excellent correlation for EF (r= 0.82, p < 0.001) and LA volumes.

Conclusions. The DHM software is feasible, accurate and quick in a large series of unselected patients, including those with suboptimal 2D images or in atrial fibrillation.

Table 1 DHM quality Adjustment Feasibility Good Suboptimal Minor Major Total of patients (n, %) 522/600 (87%) 327/522 (62%) 195/522 (28%) 149/522 (29%) 38/522 (6%) Normal subjects (n, %) 39/40 (97%) 23/39 (57%) 16/39 (40%) 9/39 (21%) 1/39 (3%) Atrial Fibrillation (n, %) 59/73 (81%)* 28/59 (47%) 31/59 (53%) 15/59 (25%) 6/59 (10%) Valvular disease (n, %) 271/312 (87%) 120/271 (%) 151/271 (%) 65/271 (24%) 16/271 (6%) Coronary artery disease (n, %) 47/58 (81%)* 26/47 (46%) 21/47 (37%) 16/47 (34%) 5/47 (11%) Miscellaneous (n, %) 24/25 (96%) 18/24 (75%) 6/24 (25%) 5/24 (21%) 3/24 (12%) Feasibility of DHM, image quality and need to adjustments in global population and in each subgroup. Abstract Figure 1

Comparison between two anticoagulant regimens to prevent thrombosis in atrial fibrillation: an analysis mediated by transesophageal echocardiography

Funding Acknowledgements

Type of funding sources: None.

Background. Atrial fibrillation (AF) is the most common cardiac arrhythmia causing left atrial appendage thrombosis (LAA-T) which can result in cerebral and systemic embolism. Nowadays, both vitamin K antagonists (VKA) and Direct Oral Anti Coagulants (DOAC) are effective for the prevention of ischaemic stroke in AF. Transesophageal echocardiography (TEE) is the best method to detect LAA-T in AF. However, data on the prevalence of LAA-T are lacking.

Purpose. The aim of the study was 1) to evaluate the prevalence of LAA-T in patients affected by AF, receiving different anticoagulation regimens and candidates to cardioversion or catheter ablation 2) to correlate the presence of LAA-T with clinical and echocardiographic data.

Methods. This is an observational, single-center study including 796 patients (73% male) with AF. TEE before cardioversion or catheter ablation was performed in all patients. Patients with mechanical prosthetic valve and severe mitral stenosis were excluded. Patients were divided in 2 groups according to anticoagulation regimen: Group 1 including patients on DOAC (dabigatran, rivaroxaban, apixaban, edoxaban) and Group 2 including patients on VKA at therapeutic dose.

Results

Group 1 included 369 patients (46%), Group 2 427 (54%). Age, CHA2DS2-VASc score, sex and pathology distribution (lone FA, hypertension, valve disease, ischemic cardiomyopathy, dilated cardiomyopathy, hypertrophic cardiomyopathy) were similar in the 2 groups. The overall prevalence of LAA-T was 43 cases (5%). Similar percentage of LAA-T was found regardless of anticoagulation regimen (Group 1: 16 cases, 4%; Group 2: 27 cases, 6%, p = 0.220). No difference in LAA-T prevalence was detected within Group 1 for different DOACs (p = 0.547). Patients with LAA-T were more frequently older (p = 0.023), female (p = 0.001), with higher CHA2DS2-VASc score (p = 0.002), affected by hypertrophic cardiomyopathy (p = 0.019), valve disease or bioprostetic valve (p = 0.001) regardless of anticoagulation regimen. A total of 697 patients (88%) were scheduled for cardioversion or catheter ablation. Cardioversion was successful in 667 patients (95%) without any ischemic event. Only 1 patient (0.1%) undergoing catheter ablation had a major ischemic event.

Conclusions

Efficacy of anticoagulation with VKA and DOAC is similar in preventing LAA-T in patients with AF. However, despite optimal adherence to a therapeutic regimen, several clinical factors (age, gender, high CHA2DS2-VASc score, hypertrophic cardiomyopathy and valvular disease) were associated with higher prevalence of LAA-T. TEE guided approach to cardioversion may prevent the risk of embolic events regardless of anticoagulation regimen used.

Role of the tricuspid annulus in functional tricuspid regurgitation development after early isolated mitral valve surgery: is it an old story?

Funding Acknowledgements

Type of funding sources: None.

Background. Functional Tricuspid Regurgitation (FTR) has been described as a common condition after isolated mitral valve (MV) surgery, affecting patients’ prognosis. Thus, in cases without significant tricuspid regurgitation (TR) but tricuspid annular (TA) dilatation, TV annuloplasty is currently recommended. Studies suggesting the currently used cut-off for definition of TA dilatation were based on 2D echocardiography (2DE) and included patients treated with MV surgery with heterogeneous MV disease, degree of cardiac remodeling and heart rhythm. As the management of severe MR has moved towards an earlier surgical treatment, few data are available about the incidence of FTR in the population undergoing early isolated MV surgery without TR, but 2DE satisfying criteria for TA dilatation.  

Aims. To test, in patients treated with early isolated MV surgery for MV prolapse (MVP), without TR and either normal or dilated TA (i) if the currently used 2D TA cut-off is predictive of FTR and cardiac events development (ii) how right chambers’ remodeling assessed by 3D echocardiography (3DE) affects TA dimension.

Methods. We studied 159 patients (age 61 ± 11) treated with early isolated MV surgery between 2010 and 2017. Eligible patients were those with 3DE images; normal left and right ventricular (LV and RV) function; sinus rhythm; normal or elevated right ventricular systolic pulmonary artery pressure (sPAP); normal or dilated TA by 2DE; absent TR. The decision to not perform TV annuloplasty in patients with TA dilatation was based on the surgical inspection. All patients underwent a complete 2DE, 3DE analysis was performed using custom software, including LV, RV, left atrial (LA) and right atrial (RA) assessment. 3D TA dimension were obtained using MPR. Clinical and 2DE follow-up was performed at 36 ± 6 months after surgery, major adverse cardiac events (MACEs, including cardiac hospitalization, cardiac death, arrhythmias) and FTR were recorded.

Results. Based on 2DE TA dimensions, patients were divided in group 1 (N = 68, 43%, TA≥21 mm/m²) and group 2 (N= 91, 57%, normal TA). Patients in group 1 showed larger RA volume, RV basal diameter and TA area (p < 0.05) by 3DE compared to group 2 (Table). At the multivariate analysis, only the 3D RA volume, RV basal diameter and RV function were independently correlated to the TA area (p < 0.05). At the follow-up, no differences were noted between groups in FTR development and MACEs at the Kaplan-Meier analysis (Fig.). At the COX analysis, 2DE TA dilatation failed to result a predictor of cardiovascular events (model’s X2, p > 0.05).

Conclusions. In patients undergoing early MV surgery, the currently defined TA dilatation by 2DE may not necessarily evolve in FTR, and a larger cut-off may be needed. In this population, the evaluation of right chambers’ dimension and function may better define the probability to develop FTR.

Abstract Figure. Fig

P734 Feasibility and accuracy of the new automated software dynamic heart model in an unselected population

Objective

Preliminary studies showed the accuracy of machine learning based automated dynamic quantification of left ventricular (LV) and left atrial (LA) volumes. We aimed to evaluate the feasibility and accuracy of this new Dynamic Heart Model (DHM) software in an unselected population undergoing transthoracic echocardiography (TTE). Methods. We enrolled 91 consecutive unselected patients (80% in sinus rhythm) referred for clinically indicated 2D TTE, who also underwent single 3D TTE image acquisition from the apical 4-chamber view. 2D images were analyzed to measure ejection fraction, LV and LA volumes; 3D images were analyzed using Dynamic Heart Model (DHM) software (Philips Healthcare), which automatically measures chamber volumes throughout the cardiac cycle, resulting in LV and LA volume-time curves. Average time of analysis, feasibility, image quality were recorded and results compared between the 2D and 3D techniques. Results. Quality of the 91 2D TTE images was graded as poor (N = 13), satisfactory (N = 45) and good (N = 33). The use of DHM was feasible in 79/91 cases (87%). The remaining 12 datasets could not be analyzed because of poor images (N = 10) or incorrect automated border detection (N = 2): in these cases, the software did not accurately identify endocardial borders due to LV cavity near obliteration or extreme LA enlargement. When feasible, the boundary position was considered accurate in 61/79 patients (77%), while minor manual correction of the LV/LA borders was needed in the remaining cases. In only 1 case the reconstruction was considered unreliable because it needed major corrections. The overall time required to obtain DHM data was approximately 45 seconds. In all cases in which DHM was used, not only shapes of LV and LA were very well defined, but also functional curves were physiologically plausible. Even in the 13 patients in whom the 2D image was suboptimal, the DHM was not only feasible but also accurate endocardial boundaries in 8 cases, without (N = 5) or with only minimal manual corrections (N = 3). As expected, 3D LV volumes were slightly hige than 2D ones ( EDV 153.9 ± 59.8 vs 121.4 ± 47.3 mL, respectively), while LV EF and LA volumes were similar (EF 58.8 ± 11.8 vs 59 ± 11.8% and LA volume 92 ± 39.3 vs 83.4 ± 32.1 mL, respectively). Conclusions. The new DHM software is quick, feasible and accurate in the majority of unselected patients, including those with suboptimal 2D images or in atrial fibrillation. Introduction of this automated analysis into clinical practice can reduce examination time, while providing reliable information not only on volumes but also on function of the left heart chambers.

1048 Evaluation of mitral annular disjunction in mitral valve prolapse: is echo imaging enough?

Funding Acknowledgements

None

Background

The separation between the atrial wall-mitral valve (MV) junction and the left ventricular (LV) attachment (mitral annulus disjunction, MAD) is a recently discovered feature linked to MV prolapse (MVP). It is associated to higher complexity of MV lesions and is possibly responsible for mechanically induced fibrosis of the LV inferobasal wall and consequently for malignant ventricular events. MAD has been described in different studies evaluating the MV either by transthoracic (TTE) or transoesophageal (TOE) echocardiography or by cardiac magnetic resonance (CMR).

Purpose

The aim of the present study was to assess MAD and compare the ability of identifying and localizing MAD with different imaging techniques in a cohort of patients with MVP and severe mitral regurgitation eligible for surgery.

Methods

A total of 108 patients with MVP requiring surgery and undergoing CMR and TTE were enrolled in the study. Ninety of them underwent also intraoperative TOE. MAD was defined as any distance observed between the atrial wall-MV junction and the LV wall at end-systole. It was retrospectively assessed in the long axis views (4-, 3-, 2-chamber) and compared between the 3 imaging techniques.

Results

MAD was identified in 18 out of 108 patients at TTE (16.7%), in 15 among 90 patients undergoing TOE (16.7%) and in 42 patients at CMR (38.9%). Comparing data per patient regardless of MAD localization, a good correlation in identifying MAD was obtained between TTE and TOE (Kendall’s τ coefficient 0.83, p < 0.001); a lower but still significant correlation was observed between TTE and CMR (τ coefficient 0.46, p < 0.001) and between TOE and CMR (τ coefficient 0.39, p < 0.001). Higher Kendall rank correlation coefficients were obtained comparing data per view (TTE vs. TOE: τ coefficient 0.86, p < 0.001; TTE vs. CMR: τ coefficient 0.48, p < 0.001; TOE vs. CMR: τ coefficient 0.42, p < 0.001). Considering only patients with MAD (Figure 1), the agreement rate between TTE and TOE (14 patients) in identifying MAD in the same view was 95%, whereas a lower agreement was observed between TTE and CMR (79% in 16 patients) and between TOE and CMR (67% in 13 patients). MAD measured 7.5 ± 1.9 mm at TTE, 6.3 ± 1.7 mm at TOE and 6.9 ± 3.4 mm at CMR.

Conclusion

In surgical MVP patients, MAD showed a higher prevalence at CMR and a lower detection rate by echo imaging. Therefore, an integrated imaging approach could be necessary in the evaluation of MVP. This relatively mild separation of the atrial wall-MV junction and LV myocardium may probably be better recognized by CMR due to a higher spatial resolution. Echo is fundamental for the anatomic and haemodynamic characterization of the valvulopathy by itself, while CMR may better define MAD and myocardial fibrosis helping the physician in identifying PVM patients with higher arrhythmic risk independent of mitral regurgitation grade.

Abstract 1048 Figure 1

P1424 Long-term follow-up in patients undergoing early surgery (repair) for severe degenerative mitral regurgitation

In conclusions

a) early MV repair is associated with favourable LV remodelling and stable systolic function at FU; b) 2DTTE predicts in an early surgical strategy favourable LV remodelling c) pre-operative 3DTTE morphology (simple vs complex MVP) predicts repair procedure (simple vs complex) that in the large majority (91%) is associated with freedom from MR recurrence.

Table Pre-op 6-month FU 3-years FU Left ventricular end diastolic volume (ml) 140 ± 41 104 ± 30 * 103 ± 35 Left ventricular end systolic volume (ml) 49 ± 19 45 ± 19* 43 ± 22 Left ventricular ejection fraction (%) 65 ± 7 58 ± 8* 59 ± 7§ Mitral regurgitation (+) 3.9 ± 0.2 0.6±.6* 0.9±.9§ Left atrial volume (ml) 123 ± 48 91 ± 35* 87 ± 45 *= p < 0.01 6 ms vs pre-op; §=p < 0.01 3ys vs 6 ms

P1799 The importance of 3D imaging techniques in left atrial appendage closure: landing zone eccentricity influence on peri-device leak incidence and its implication in long-term clinical outcomes

Background

A complex left atrial appendage (LAA) morphology and a non-circular landing zone (LZ) are frequently encountered in patients undergoing percutaneous LAA occlusion (LAAO). Three-dimensional (3D) imaging modalities as 3D transoesophageal echocardiography (3D TOE) and cardiac computed tomography (CCT) should be preferred over two dimensional techniques for better evaluation of LAA diameters, especially for the LZ. In fact, non-circular shape could impair the choice of occluder device size and may be implicated in the occurrence of residual leaks. Incomplete LAA occlusion is recognized to be associated with thromboembolic events.

Purpose

The aim of the study was to evaluate the utility of 3D imaging techniques to predict LAA device size and the landing zone eccentricity index as a potential predictor of residual peri-device leaks and to assess their clinical implications on long-term follow-up.

Methods

It was a retrospective, single-center study including 137 consecutive patients undergoing successful LAAO from January 2010 to July 2018. Pre-procedural 3D TOE and CCT were used to predict device size based upon LZ diameters and quantify LAA orifice eccentricity. Leaks were defined as the presence of peri-device flow at 2D TOE immediately after the device implantation and at 3 months follow-up. Leaks were classified as significant (color jet width ≥4 mm) or minor (<3 mm). A clinical evaluation of thromboembolic events was performed at 48 ± 27 months from the procedure.

Results

LAAO closure was performed implanting either Amulet or Watchman devices (n = 98 and n = 40, respectively). The assessment of LZ measurements with 3D TOE and CCT showed a significant correlation with the device size selected on the basis of 2D techniques (r = 0.82 and r = 0.74, respectively). As concerns the peri-device leaks, the presence of an eccentric LZ (eccentricity index >0.20) was not associated to the development of post-procedural leaks in the overall population; a significant correlation was detected only in the subgroup of patients treated with the Amulet device (p = 0.045). Residual leaks included only 1 significant leak (0.7%) after Amulet device implantation, which was related to a major neurological event (stroke) and 47 (34%) minor leaks (n = 28 in the Amulet group, n = 19 in the Watchman group). In this last population, 2 patients (1.5%) developed minor neurological events (transient ischemic attack).

Conclusions

3D TOE and CCT better predict device size overcoming the limit of 2D imaging techniques undersizing. In eccentric LAA, Watchman device may reduce the incidence of peri-device leaks. The presence of significant residual leaks is uncommon but associated with major clinical events, whilst minor leaks are relatively frequent but do not seem to be related to life-threatining thromboembolic accidents.

624 Is TAVI a useful procedure in paradoxical low flow-low gradient aortic stenosis? A long-term mortality study

Background

Clinical outcomes of patients with paradoxical low-flow, low-gradient aortic stenosis (PLF-LG) undergoing valve replacement are controversial. PLF-LG is a combination of a small aortic valve area (AVA < 1cm²), a preserved left ventricular (LV) ejection fraction (LVEF≥50%), and a ‘paradoxical’ low mean gradient due to the presence of low LV stroke volume (≤35 mL/m²). The low flow state is explained by the presence of a high afterload and pronounced LV concentric remodeling, with impaired LV filling. Surgical aortic valve replacement has been associated with very positive outcomes in normal-flow high-gradient (NF-HG) AS, whereas poorer outcomes has been reported in patients with PLF-LG AS.

Purpose

The aim of this study is to determine the clinical outcomes in patients with PLF-LG AS undergoing transcatheter aortic valve implantation (TAVI) compare to NF-HG patients.

Methods

A total of 624 patients (age 81 ± 7 years) with symptomatic severe AS and preserved LVEF who underwent TAVI, was enrolled and divided in 2 groups: group NF-HG included 554 patients (89%) and group PLF-LG including 70 patients (11%). At 1-year follow-up, death and clinical events were reported.

Results

TAVI was feasible in all patients. A significant reduction in mean aortic pressure gradient was observed after TAVI both in PLF-LG (baseline, 30 ± 6 mmHg; 1-year, 12 ± 4 mmHg; p < 0.001) and in NF-HG (baseline, 55 ± 12 mmHg; 1-year, 11 ± 4 mmHg; p < 0.001) together with an increase in AVA (PLF-LG: baseline, 0.73 ± 0.16 cm², 1-year: 1.82 ± 0.43 cm², p < 0.001; NF-HG: baseline, 0.66 ± 0.18 cm², 1-year: 1.84 ± 0.38cm², p < 0.001). Perioperative mortality at 30-days was similar in group NF-HG (17/554, 3%) and in group PLF-LG (2/70, 3%). Figure shows the survival curves up to 5 years follow-up according to the two groups. PLF-LG and HG-AS had similar survival rate throughout the long-term follow-up. Similarly, rehospitalization rate was not different in the two groups (PLF-LG: 12% vs NF-HG: 7%, p = 0.127).

Conclusions

Differently from surgical series, TAVI in PLF-LG AS is a useful procedure showing similar mortality and rehospitalization rates compared to NF-HG AS patients.

Abstract 624 Figure. Survival curve

P3368Mitral annulus disjunction retrospective assessment by transthoracic and transoesophageal echocardiography in a large cohort of patients with mitral valve prolapse and significant mitral regurgitation

Background

The separation between the atrial wall-mitral valve junction and the left ventricular attachment (mitral annulus disjunction, MAD) is a recently discovered feature associated with Barlow's disease (BD). Correlations between MAD and morpho-functional alterations of the mitral valve (MV) apparatus have been described and different prevalence rates of MAD have been reported by several authors, analysing small sample size populations of patients with mixomatous MV prolapse (MVP).

Purpose

Aims of the study were 1) to estimate the prevalence and to assess MAD in a large cohort of patients with MVP (either BD or fibroelastic deficiency, FED) and significant mitral regurgitation with indication for surgical correction conforming to guidelines; 2) identification of any correlation between MAD and the MV anatomy, MVP aetiology and general characteristics of the study population.

Methods

A total of 979 patients presenting at our Centre from 2007 and 2018 with MVP and moderate-to-severe or severe mitral regurgitation were enrolled in the study. All patients underwent pre-operative transthoracic echocardiography (TTE) and 792 also intraoperative transoesophageal echocardiography (TOE). All recorded images and clips were saved in a central archive and were retrospectively analysed. MAD was defined as any distance observed between the atrial wall-MV junction and the left ventricular wall; it was evaluated in all available views and measured at end-systole.

Results

The overall population included 630 patients (64.4%) affected by BD and 349 (35.6%) with FED. Assessing off-line images from TTE and/or TOE, MAD was identified in 161 (16.4%) patients, respectively 21% and 8% in the BD and FED subgroups. Maximal MAD distance measured 6.6±2.2 mm at TTE and 6.7 mm ± 2.2 mm at TOE. Comparing MVP patients with and without MAD, it emerged that MAD was associated with younger age (60±14 vs 64±13 years, p<0.001) and slightly lower BMI (23.9±3.6 vs 24.5±3.6 kg/cm2, p=0.045). As concerns the MV apparatus, the presence of MAD showed a median larger MV annulus (medio-lateral diameter 41.0 [37.0–44.0] vs 39.0 [36.0–42.0] mm, p=0.001; antero-posterior diameter 38.0 [34.0–41.0] vs 36.0 [33.0–40.0] mm, p=0.001), greater incidence of bileaflet MVP (47.8% vs 25.9%, p<0.001) and mixomatous aetiology (82.0% vs 60.9%, p<0.001) and a lower prevalence of chordal rupture (61.5% vs 75.7%, p<0.001).

Conclusion

MAD significantly correlates with specific anatomical MV characteristics. Its prevalence results to be lower than reported in previous studies performed in different clinical contexts. In MVP population with surgical indication, MAD is clearly associated to BD, but it is also observed in a minority of patients with FED

Acknowledgement/Funding

None

P594Contrast transthoracic echocardiography as a gatekeeper for patent foramen ovale closure

Background.

The presence of patent foramen ovale (PFO) has been linked to many illness, including cryptogenic stroke, transient ischemic attack, migraine, platypnea-orthodeoxia syndrome and decompression sickness in scuba divers. Transesophageal echocardiography is the gold standard technique for the visualization of atrial septal anatomy, but it is a secondary level exam, not always available, with additional associated costs and not completely free from procedural risks. Standard transthoracic echocardiography (TTE) has a too low sensitivity for PFO screening.

Purpose.

The aim of the study was to assess the role of TTE associated with agitated saline contrast injection (contrast-TTE) as a gatekeeper for the identification of PFO in a large cohort of patients undergoing selection for percutaneous closure.

Methods.

A total of 200 patients undergoing a diagnostic work-up for the identification of PFO was imaged by contrast-TTE at rest and after provocative maneuvers (PM: Valsalva in all cases). Contrast TTE was graded from 0 to 4 on the bases of bubbles counting (0: no bubbles; 1: < 10 bubbles; 2: 10-30 bubbles; 3: >30 bubbles; 4: complete LV opacification). PFO closure was performed after a consensual clinical decision by the cardiologist and the neurologist taking into account comprehensive imaging, clinical evaluation and thrombophilia screening. PFO closure was always monitored by intracardiac echocardiography.

Results.

At baseline contrast TTE was positive (≥2) in 34 patients (17%) while contrast TTE with PM was positive in 94 cases (47%). 27 out of 200 patients (14%) had an interatrial septal aneurysms. PFO closure was performed in 34 cases (17%). All of these had severe right-to-left shunting (≥3) at contrast TTE and 9 cases had also an interatrial septal aneurysms. The procedure was aborted in only 1 patient due to a complex defect anatomy.

Conclusion.

Contrast TTE with PM may be not only considered an accurate tool for the detection of PFO but may be also inserted in the diagnostic work- up as a primary gatekeeper for percutaneous closure. Severe shunting at contrast TTE influences final decision making in a large cohort of cases undergoing screening for PFO closure.

Guiding spontaneous tissue regeneration for urethral reconstruction: long-term studies in the rabbit

We designed long-term in vivo experiments to study rabbit urethral regeneration and remodelling over a hyaluronan biodegradable prosthesis. Seven months after the resection of a 1.5-cm-long tract of the urethra and its substitution with the prosthesis, radiological analysis showed the disappearance of the implant and the re-establishment of urethral continuity along the transmural defect. The regenerated tissue remodelled around the implant and exhibited good distensibility under pressure. Histological evaluation showed that the neo-urethra was lined with transitional epithelium and the stroma contained abundant elastic fibres. An examination of the pattern of the major cytoskeletal and cytocontractile proteins of smooth muscle cells and fibroblasts was able to distinguish fibroblasts from smooth muscle cells and myofibroblasts in the neo-urethra. These experiments provide evidence for the potential, successful use of biocompatible/bioresorbable devices for reconstructive surgery of the urethra.

Reconstructive surgery of the urethra: a pilot study in the rabbit on the use of hyaluronan benzyl ester (Hyaff-11) biodegradable grafts

We investigated the outcome of reconstructive surgery of the urethra through guides composed of a novel biodegradable and highly biocompatible polymer, Hyaff-11. A tract of about 1.5 cm of the rabbit pendulous urethra was totally resected and replaced by a Hyaff-11 tubular graft. Eleven animals were analysed at each of the time points ranging from 7 days to 4 weeks following surgery. Histological and radiological evaluation showed a satisfactory remodelling of the neo-urethra around the implant. The regenerated connective tissue connected both urethral stumps within the first 7 days. On postoperative week 3, the Hyaff-11 guide had disappeared. At the 4-week time point the retrograde urethrogram showed a good distensibility of the neourethra. The regenerated stroma consisted of fibroblastic cells, and collagenous and elastic fibres. The neo-epithelium was pluristratified and exhibited cells of the cuboidal type.

Changes of acute-phase proteins in streptozotocin-induced diabetic rats

Quantitative and qualitative changes of serum proteins, apart from glycation, have not been sufficiently studied in streptozotocin-induced diabetic rats (D), the most common experimental model for diabetes. Thus, we decided to analyze the serum of diabetic rats by concanavalin A-blotting in comparison with rats with acute inflammation induced by fermented yeast (Y), in which characteristic alterations of serum proteins have been described. Two months after the streptozotocin treatment, the blood glucose levels were highly elevated (456+/-24 vs. 124+/-10 mg/dl, p<0.001, n=12), the body weight was significantly lower than normal (279+/-10 vs. 392+/-6 g, p<0.001, n=12), and serum proteins appeared to be highly glycated (p<0.001) when analyzed by the fructosamine assay, without any significant change in the total serum protein concentration. Analysis by concanavalin A-blotting, revealed a significant decrease of alpha1-inhibitor-3 (alpha1-I3, p<0.05) and an increase of the beta chain of haptoglobin (beta-Hp, p<0.05) in both D and Y rats (n=3) compared with control animals. However, acute inflammation caused a marked rise of two prominent acute phase proteins, alpha2-macroglobulin and hemopexin, which did not change appreciably in diabetic rats. Further work will be necessary to evaluate the physiopathological significance of these phenomena which could result from changes of both concentration and glycosylation of the aforementioned proteins.

Functional response of cavernosal tissue to distension

We studied rabbit isolated erectile tissue responses to changes in preload and to active tension development with norepinephrine. The effects of antagonists of endothelin-1, prostaglandins E2 and F2alpha and of nitric oxide were also tested on normal and de-endothelialized preparations. Tissue distension was found to elicit spontaneous rhythmic contractions. Increase in preload diminished the latency of the spontaneous activity and augmented the developed force. Active tension development and the inhibitor of the Na+,K+ pump, ouabain, opposed the spontaneous activity. A marked reduction in the resting tension with abolition of the spontaneous activity was observed on normal, but not on de-endothelialized tissues, following the addition of the specific prostaglandin E2 and F2alpha receptor antagonist, SC-19220. At 3 x 10(-4) M, the highest concentration used, the endothelin-A receptor antagonist BQ-123 failed to change the pattern of the spontaneous activity and the resting tension of normal tissues. The nitric oxide synthesis inhibitor, L-NAME, did not produce reliable effects. These findings point to a causal relation between cavernosal tissue distension and phasic and tonic contractions. Phasic contractions appear to be elicited by smooth muscle cells through the enzyme Na+,K+-ATPase. Increase in the resting tone could be mediated, at least in part, by the endothelium, through the release of prostaglandins E2 and/or F2alpha but not of endothelins. We discuss the hypothesis that, in cavernosal tissue, mechanotransduction of distension to contractile responses is an important determinant of detumescence.

Chronic treatment with cyclosporine A in New Zealand rabbit: aortic and erectile tissue alterations

Transplanted patients frequently present erectile impotence. In order to test any interference by cyclosporine A (CsA), which is commonly used in the post-transplantation management, we investigated the in vitro contractile and relaxant responses of corpus cavernosum and aorta from rabbits chronically treated with CsA. Male New Zealand White rabbits 6 months of age were treated with CsA (25 mg/kg per day s.c.) or solvent (corn oil) for 3 weeks. Descending thoracic aorta and erectile tissue were studied in vitro at the end of treatment. Isometric tension was recorded. In thoracic aorta, noradrenaline (0.1-30 mM) induced a concentration-dependent contraction with no difference between the two groups. Acetylcholine (30 nM-3 mM) produced relaxation (52 +/- 4% at 1 mM) that was significantly reduced in comparison to controls (67 +/- 4%, P < 0.05). ATP (3-10 mM) relaxation was not significantly different (maximal 78 +/- 10% and 62 +/- 12% in CsA-treated and controls). The relaxation produced by sodium nitrite was reduced in CsA-treated rabbits (at 10 mM and 0.1 mM concentrations). In erectile tissue, no significant variation in the response of isolated erectile tissue to the above drugs was observed between CsA-treated and control animals. These data indicate that chronic treatment with CsA in rabbits, despite alteration of the in vitro response of thoracic aorta, does not directly influence the function of penile tissue with relaxants.

Characterization of in vitro relaxant mechanisms in erectile tissue from rabbits of different ages

In the present study we investigated the in vitro relaxant response of erectile tissue obtained from rabbits of different ages (3, 7 and 24 months) in order to detect the progression with age of cavernosal activity in response to substances acting via endothelium-dependent or -independent mechanisms. Noradrenaline induced a concentration-dependent contraction (0.1 microM-3 mM), with an increase in the contractility in the 24-month-old group. Acetylcholine produced a concentration-dependent relaxant effect in the three age groups, with a reduction of the maximal relaxant effect in older animals. ATP (10 microM-1 mM) and adenosine (10 microM-1 mM) induced a concentration-dependent relaxant effect that was higher in the older group. The presence of the NO2-synthase inhibitor N omega-nitro-L-arginine methyl ester (L-NAME) (0.1 mM) or of the P2-purinoceptor antagonist suramin did not affect ATP relaxation. Relaxation induced by sodium nitrite and nifedipine was reduced in older animals. In conclusion, aging selectively alters the in vitro responsiveness of rabbit erectile tissue. Purinergic system remains more active despite a decrease in the maximal endothelial cholinergic activity and the direct smooth muscle relaxant component.

Effects of prostaglandin E1, and papaverine on non-neurogenic and neurogenic contraction of the isolated rabbit erectile tissue

Experiments were performed to get further insights into the erectogenic mechanism of prostaglandin E1 (PGE1), which was compared to that of papaverine (PAP). PGE1 and PAP were effective in abolishing the contraction induced by N-ethylmaleimide (NEM), an adenylate cyclase blocker. However, preincubation with PGE1 but not with PAP markedly attenuated the amplitude of adrenergic nerve mediated contraction following prolonged electrical field stimulation. Preincubation with PGE1 was ineffective in counteracting the increase in tension due to exogenous norepinephrine. These data together with previous studies corroborate the hypothesis that in the presence of PGE1 a dual erectogenic mechanism takes place in modulating the cyclic-adenosine-monophosphate metabolism of the cavernous smooth muscle cell as well as the release of norepinephrine from the sympathetic terminal.

Bladder function in the aged rat: a functional and morphological study

This study was designed to characterize urinary bladder function in the aged rat (27 months of age). For comparative purposes, two different control groups were included into the experimental protocol: normal 6-month old and hyperdiuretic 6-month old rats. Increased threshold volume for micturition and increased bladder mass were found in both aged and hyperdiuretic rats. No difference in the amplitude of micturition contractions was detected between groups. In the aged rat, but not in the hyperdiuretic one, augmented threshold volume and bladder mass were associated with increased intravesical pressure at micturition and structural changes of intramural bladder innervation. When activated, the vesicovesical reflex did not show any change in terms of rate of isovolumetric contractions. In the aged rat, altered sensory information on the state of maximum fullness seems to play an important role in determining abnormal cystometric findings.

A simplified in vitro preparation of the corpus cavernosum as a tool for investigating erectile pharmacology in the rat

This work describes a simple technique for the assessment of corpus cavernosum function in a species, the rat, representing a convenient model for basic research. We obtained measurable and reproducible responses to different pharmacological agents as well as to electrical field stimulation. In view of the present results we conclude that isolation of the erectile tissue together with the septum may constitute a valuable experimental tool for investigating both local erectile mechanisms and the action of drugs, in the rat corpus cavernosum. Data obtained in the presence of N-nitro-L-arginine and methylene blue further reinforce the concept that nitric oxide may be involved in the process of erection in the rats as well as in other animal species.

Ultrastructural analysis of the cavernous and dorsal penile nerves in experimental diabetes

The present study was designed to investigate whether experimental diabetes determines structural changes in peripheral nerves involved in reflexogenic erection, namely the cavernous and the dorsal nerve of the penis. Myelinated axons were examined in the dorsal nerve of the penis from rats with streptozotocin-induced diabetes (3- and 6-month duration). Morphometric analysis disclosed a significant decrease of myelinated fibre size most likely due to a progressive axonal atrophy. In addition, morphological analysis revealed diffuse accumulation of glycogen within axons, lipid droplets in Schwann cells and pronounced sequestration of axoplasm by adaxonal Schwann cell processes. These signs were particularly prominent in 6-month-diabetic rats. Myelinated and unmyelinated axons of the cavernous nerve were analysed in 6-month-diabetic animals. No substantial ultrastructural abnormalities were found in the cavernous nerves. These results suggest that in experimental diabetes regionally specific structural changes occur in neuronal pathways subserving erectile function.

Electrical stimulation of the dorsal nerve of the penis evokes reflex tonic erections of the penile body and reflex ejaculatory responses in the spinal rat

An animal model using the spinal rat was characterized. Electrical stimulation of the dorsal nerve of the penis elicited reflex tonic erections of the penile body and reflex bulbospongiosus muscle activity, flips and ejaculations. The tonic erections of the penile body are independent from contractions of the bulbospongiosus muscle and appear to be the result of a neurovascular process. Our observations suggest that reflex bulbospongiosus muscle activity, flips and ejaculations are a single complex reflex response, which we define as reflex ejaculatory response. Two parameters predicted the occurrence and type of reflex response. The visualization of bulbospongiosus muscle activity during surgical isolation of the dorsal nerve of the penis was sufficient to anticipate the elicitability of reflex ejaculatory responses. The latter, together with a systemic systolic pressure > or = 73 mmHg., warranted the elicitability of reflex tonic erections. The similarities found in the physiology of rat tonic penile body erections and of human erections make this model promising for further elucidation of sexual function. Moreover, the present model may prove useful for the investigation of neurogenic erectile dysfunction, and of neurogenic ejaculatory disorders.

Effect of streptozotocin-induced diabetes on electrically evoked erection in the rat

This study was designed to investigate whether experimental diabetes in rats could functionally affect reflexogenic erection. Erection was elicited by means of electrical stimulation of the dorsal nerves of the penis and recorded as intracorporeal pressure. Rats were examined 1, 3 and 6 months after diabetes induction by streptozotocin. Three and 6 month diabetes caused a significant decrease of latency for erection and a slower phase of detumescence when compared to age-matched controls. In addition, a trend for a lower developed intracorporeal pressure was present in the 6 month diabetes group. Our results indicate that experimental diabetes is associated with alterations of reflexogenic erection.

Functional responses of hindlimb circulation in aged normal and WHHL rabbits

Normal New Zealand and Watanabe heritable hyperlipidemic (WHHL) rabbits, about 24 months old, were prepared, under anaesthesia, for recording blood pressure and hindlimb blood flow. Changes in hindlimb vascular resistance were measured after local intra-arterial bolus injection of increasing doses of acetylcholine, bradykinin, serotonin, sodium nitroprusside and phenylephrine. In WHHL rabbits basal hindlimb blood flow was reduced (from 22.6 +/- 3.0 to 12.5 +/- 1.8 ml/min; P less than 0.05) and hindlimb vascular resistance was increased (from 4.6 +/- 0.5 to 8.2 +/- 1.5 mmHg/ml per min; P less than 0.05). No difference was observed in response to acetylcholine, serotonin, sodium nitroprusside and phenylephrine. The only marked alteration found in WHHL rabbits was a clear deficit to bradykinin stimulation. Morphological analysis, using scanning and transmission electron microscopy, indicated a clear damage of the femoral artery, like the presence of atherosclerotic plaques, and an abnormal distribution of patent microvessels in the WHHL muscles of the leg. Peripheral circulation in WHHL rabbits shows some peculiar features, like increased basal vascular resistance and a selective impairment of bradykinin responses. Together with these abnormalities, it seems that responses to various other dilating or contracting agents are normal, suggesting that in this interesting animal model of atherosclerosis the alterations are more specific than in other models.

Urine retention due to intra-spinal cord injection of colchicine in rats: improved recovery of bladder function by monosialoganglioside GM1 and nerve growth factor administration

Intra-spinal cord injection of a low dose of colchicine (2 micrograms/rat) at the lumbar level affects the micturition reflex leading to voiding suppression, bladder hypertrophy and overflow incontinence which lasts about four weeks. The administration of nerve growth factor and monosialoganglioside GM1 normalizes urine output within 3 days and improves recovery of the bladder contraction tested by a cystometric analysis.

Inner ester derivatives of gangliosides protect autonomic nerves of alloxan-diabetic rats against Na+, K(+)-ATPase activity defects

Bovine brain gangliosides have been shown to prevent decay in Na+,K(+)-ATPase activity in sciatic and optic nerves of alloxan- and streptozotocin-diabetic rats. In the search for a drug with greater bioavailability and increased incorporation into neural tissue, ganglioside inner ester derivatives (AGF1) were recently developed. We evaluated the effect of AGF1 treatment on Na+,K(+)-ATPase activity in homogenates of vagus nerve from alloxan-diabetic rats (100 mg/kg s.c.). Animals were treated with AGF1: 10 mg/kg 6 days/week i.p., or 30 mg/kg biweekly i.p. Treatment began 10 d post-alloxan and continued for 8 consecutive weeks. Normal age- and sex-matched rats were used as controls. Alloxan intoxication produced a 39% decrease in Na+,K(+)-ATPase activity of the vagus nerve, which was completely restored (96-97% recovery) by both AGF1 regimes. Results suggest that ganglioside inner ester derivatives may be used in the clinical setting for the management of diabetic autonomic neuropathy.

Diabetic autonomic neuropathy and bladder function: pharmacological use of gangliosides and insulin

This paper briefly describes experimental evidence indicating that bladder dysfunction observed in diabetic rats is due in part to hyperdiuresis and in part to autonomic nerves alterations. The latter, in analogy with somatic nerves alteration, can be ameliorated by treatment of diabetic animals with gangliosides. The use of this agent in the autonomic nerve dysfunction of diabetic origin is discussed.

Cystometric changes in alloxan diabetic rats: evidence for functional and structural correlates of diabetic autonomic neuropathy

Autonomic neuropathy and urinary bladder function were compared in Sprague-Dawley rats with alloxan-diabetes of 3 months duration, rats fed sucrose for 8 weeks, and rats examined 8 weeks after pelvic nerve surgical axotomy; normal age-matched rats were used as controls. All experimental interventions induced bladder hypertrophy with increased bladder weight. In diabetic and sucrose-fed animals, water intake and urinary output increased. Cystometric recordings of normal rats in vivo showed rhythmic contractions (1.25 +/- 0.25 contr/min) with threshold volume for micturition reflex at 0.51 +/- 0.04 ml. In diabetic rats, bladder contractions were irregular and of lower frequency (0.60 +/- 0.04 contr/min), while threshold volume was significantly higher (1.00 +/- 0.11 ml). Bladder contractions were normal in sucrose-fed animals, though threshold volume was markedly augmented (1.27 +/- 0.19 ml). Pelvic nerve surgical ablation abolished micturition reflex. In bladder strips excised post-mortem, contractile response to field stimulation was reduced in diabetic rats compared to control and sucrose-fed animals. Morphological examination of pelvic and hypogastric nerves revealed abnormalities characteristic of diabetic neuropathy only in diabetic rats. These data suggest that in alloxan-induced diabetes the decrease in the rate of bladder contraction is the result of autonomic neuropathy; while bladder hypertrophy in sucrose-fed rats appears to be an organ adaptation to hyperdiuresis.