Electrocardiogram analysis in Anderson-Fabry disease: a valuable tool for progressive phenotypic expression tracking

Background

Electrocardiogram (ECG) has proven to be useful for early detection of cardiac involvement in Anderson-Fabry disease (AFD); however, little evidence is available on the association between ECG alterations and the progression of the disease.

Aim and Methods

To perform a cross sectional comparison of ECG abnormalities throughout different left ventricular hypertrophy (LVH) severity subgroups, providing ECG patterns specific of the progressive AFD stages. 189 AFD patients from a multicenter cohort underwent comprehensive ECG analysis, echocardiography, and clinical evaluation.

Results

The study cohort (39% males, median age 47 years, 68% classical AFD) was divided into 4 groups according to different degree of left ventricular (LV) thickness: group A ≤ 9 mm (n = 52, 28%); group B 10-14 mm (n = 76, 40%); group C 15-19 mm (n = 46, 24%); group D ≥ 20 mm (n = 15, 8%). The most frequent conduction delay was right bundle branch block (RBBB), incomplete in groups B and C (20%,22%) and complete RBBB in group D (54%, p < 0.001); none of the patients had left bundle branch block (LBBB). Left anterior fascicular block, LVH criteria, negative T waves, ST depression were more common in the advanced stages of the disease (p < 0.001). Summarizing our results, we suggested ECG patterns representative of the different AFD stages as assessed by the increases in LV thickness over time (Central Figure). Patients from group A showed mostly a normal ECG (77%) or minor anomalies like LVH criteria (8%) and delta wave/slurred QR onset + borderline PR (8%). Differently, patients from groups B and C exhibited more heterogeneous ECG patterns: LVH (17%; 7% respectively); LVH + LV strain (9%; 17%); incomplete RBBB + repolarization abnormalities (8%; 9%), more frequently associated with LVH criteria in group C than B (8%; 15%). Finally, patients from group D showed very peculiar ECG patterns, represented by complete RBBB + LVH and repolarization abnormalities (40%), sometimes associated with QRS fragmentation (13%).

Conclusions

ECG is a sensitive tool for early identification and long-term monitoring of cardiac involvement in patients with AFD, providing "instantaneous pictures" along the natural history of AFD. Whether ECG changes may be associated with clinical events remains to be determined.

Diagnostic pathways leading to arrhythmogenic left ventricular cardiomyopathy in a single center cohort

Background

Despite major advances, the recognition of arrhythmogenic left ventricular cardiomyopathy (ALVC) remains challenging, since this clinical entity is often concealed in different clinical settings both in terms of clinical onset and imaging phenotype, resulting in significant delays in diagnosis with prognostic implications.

Purpose

To describe a single Center cohort of ALVC patients, focusing on the spectrum of clinical presentation and diagnostic pathways.

Methods

Patients were retrospectively evaluated between January 2012 and January 2022. Diagnosis was based on 1) ≥3 contiguous segments with subepicardial/midwall LGE in the LV at cardiac magnetic resonance (CMR) plus a likely pathogenic/pathogenic arrhythmogenic cardiomyopathy (ACM) associated genetic mutation and/or familial history of ACM and/or red flags for ALVC (i.e, negative T waves in V4–6/aVL, low voltages in limb leads) or 2) pathology examination of explanted hearts/autoptic cases suffering from sudden cardiac death (SCD). Patients with significant right ventricular involvement were excluded.

Results

Sixty-six patients were evaluated for suspected ALVC: 8 phenocopies were excluded (6 acute myocarditis and 2 sarcoidosis) after a comprehensive clinical and multi-modality instrumental evaluation. The final study cohort was composed by 56 patients (55% males, median age 45 years), from 36 families. Diagnostic pathways leading to diagnosis were: SCD in 4 (7%), ventricular arrhythmias in 11 (20%), chest pain in 9 (16%), heart failure in 7 (12%), and familial screening in 25 (45%) (Figure 1). An echocardiogram was available for all but 2 patients with SCD: 25 (46%) had normal phenotype, 17 (32%) had a hypokinetic non dilated cardiomyopathy, and 12 (22%) had a dilated cardiomyopathy (DCM). Of the 49 tested patients, 31 (63%) had a pathogenic/likely pathogenic DNA variant: desmoplakin (DSP, N=21), filamin C (FLNC, N=4), SCN5A (N=3) were the most frequently involved genes; 8 patients had a double gene mutation. Twenty-four patients (43%) had previously received a diagnosis other than ALVC: 10 idiopathic DCM, 9 acute myocarditis, 4 post-myocarditis DCM, 2 acute myocardial injury/non-ST elevated myocardial infarction. In 13 patients ALVC was diagnosed with the introduction of CMR in the diagnostic work-up of a DCM, in 2 cases the diagnosis was done with the pathology examination after heart transplantation. The median diagnostic delay was of 8 years, with a maximum of 20 years. It is worth nothing that patients from the same family might have different diagnostic pathways and phenotypes of ALVC (Figure 2).

Conclusions

ALVC is a challenging diagnosis, hidden in different clinical scenarios. Five main clinical pathways leading to ALVC diagnosis may be identified: ventricular arrhythmias, chest pain, heart failure, SCD at first presentation, and clinical/instrumental familial screening.

Funding Acknowledgement

Type of funding sources: None.

P663 Is echocardiogram alone sufficient for cardiac masses characterization?

BACKGROUND

Cardiac Masses (CM) represent an heterogeneous group with a prevalence of 0.3% at autopsy, divided in benign masses (primary tumors and pseudotumors) and malignant ones (primitive tumors and metastasis). 2-D Echocardiography is nowadays the first line approach to define nature and management of CM, but is it enough to guide a therapeutic strategy?

PURPOSE

To evaluate echocardiographic diagnosis accuracy for CM in patients admitted to our Centre between 1997 and 2017.

MATERIALS AND METHODS

We retrospectively evaluated a population of 180 consecutive patients (45% males; mean age 60 ± 16 years; BMI 25 ± 5 Kg/m2), referred to our echocardiographic lab with suspicion CM. All patients were examined in both left lateral and supine position, and heart was visualized from all available echocardiographic windows. Definite diagnosis was obtained by histologic examination of biopsy, surgical samples or, in cases of cardiac thrombi, by radiological evidence of thrombus resolution after adequate anticoagulant treatment. We excluded normal anatomical variants in the group of pseudotumors due to the impossibility of obtaining histological examination. Sensitivity, specificity, predictive accuracy for a positive test, and predictive accuracy for a negative test were calculated by standard formulas (corrected for prevalence by Bayes theorem).

RESULTS

We detected 129 benign CM and 51 malignant cardiac tumors. In 7 cases a poor acoustic window did not allow an optimal examination; in remaining 173 patients, the classical 2-D echocardiogram identified 157 masses with a diagnostic accuracy of 91%. Of 173 CM diagnosed, 146 were classified by echocardiographer as benign masses (125 true benign on histological examination) and 27 as malignant ones (all malignant after histological confirmation); the results showed 56% sensitivity, 100% specificity, 100% positive predictive value, 98% negative predictive value, with 88% overall diagnostic accuracy in identifying the nature of masses. 23 cases were undetermined and needed second level instrumental investigations to be characterized. Diagnostic accuracy for distinguishing primary benign tumors and pseudotumors decreased to 80%, with a significant increase in both "false" benign tumors (9 out of 91) and "false" pseudotumors (15 out of 34) with 85% sensitivity, 68% specificity, 10% positive predictive value, 99% negative predictive value.

CONCLUSION

2D Echocardiography is an excellent, non invasive technique for first line evaluation of patients with suspicion CM. It is safe, reliable with a high predictive value and diagnostic accuracy in identifying CM and their benign or malignant nature. In contrast, these results were insufficient to start an anticoagulant in suspicion thrombus or cardiac surgery for primary tumor, since second level instrumental examinations needed. 2D Echocardiography alone seems unuseful for classifying malignant masses in primitive or metastasis.

P6455Differences in cardiac phenotype and natural history of laminopathies with and without neuromuscular presentation

Aim

To look for differences in cardiac phenotype and natural history of patients affected by laminopathy, according to the presence or less of neuromuscular involvement at clinical presentation.

Methods

We prospectively analyzed 47 consecutive pts with a genetic diagnosis of laminopathy followed at a single centre between 1994 and 2017. Additionally, reports of clinical and instrumental evaluations before referral at our centre were retrospectively evaluated.

Results

Neuromuscular presentation, mainly as Emery-Dreifuss muscular dystrophy (EDMD), was present in 21 (46%) cases (14 LMNA and 7 EMD gene mutations). These pts had symptoms earlier (9 vs 39 years, p<0.001) in life compared to pts without neuromuscular onset (26 LMNA gene mutations), and clinical manifestations anticipated the first evidence of cardiac disease by a mean time of 15±8 years (maximum time gap of 38 years). Despite a similar prevalence of atrial fibrillation/flutter (AF) (71% vs 65%, p=0.758) and atrio-ventricular blocks (48% vs 65%, p=0.250), pts with neuromuscular onset experienced AF and pace-maker implantation at a significantly younger age (27 vs 41 yrs, p=0.015 and 23 vs 44 yrs, p=0.027 respectively). Differently a higher prevalence of sinus node dysfunction (33% vs 4%; p=0.015) and atrial paralysis (14% vs 4%; p=0.311) was reported in pts with neuromuscular onset. Prevalence of cardiomyopathy (CMP) (73% vs 33%, p=0.008) and sustained ventricular tachyarrhythmias were higher among pts with cardiac onset (23% vs 4%, p=0.111) whereas the prevalence of heart transplantations and median age of recipients were similar in the two groups (24% vs 20%, p=1.000 and 46 vs 43, p=0.592 years respectively). All pts with neuromuscular onset who received a diagnosis of CMP had a previous history of rhythm disturbance except 2 cases, where a concomitant diagnosis of the 2 disorders was formulated. On the contrary a strict temporal progression from rhythm disturbances to CMP (or viceversa) was not appreciable in the other group: AF and AVBs could precede the diagnosis of CMP be diagnosed at the same time or later.

Conclusions

In pts affected by laminopathy neuromuscular involvement, when present, was most often the first clinical manifestation and preceded cardiological involvement, with a long time frame in some cases. Except for sinus node dysfunction, much more frequent in patients with EDMD, a similar prevalence of rhythm disturbances was reported, although pts with neuromuscular clinical onset were younger at diagnosis of AF and at PM implantation. Pts without neuromuscular presentation had a higher prevalence of CMP and ventricular arrhythmias, albeit a similar rate of heart transplantation. In pts with neuromuscular onset, cardiac involvement was characterized by a stepwise progression from rhythm disturbances to CMP, where a strict temporal progression from rhythm disturbances to CMP was not observed in the group of pts without neuromuscular clinical onset.

P900Electrocardiographic findings in Anderson-Fabry disease versus sarcomeric hypertrophic cardiomyopathy

Background

Cardiac involvement is one of the most frequent and disabling organ damage in Anderson-Fabry (AF) disease, causing hypertrophic cardiomyopathy (HCM), conduction disturbances, arrhythmias and coronary disease. Differential diagnosis from sarcomeric HCM is often very challenging, especially for patients with exclusive cardiac involvement.

Purpose

To gain new insights from standard electrocardiogram (ECG) in AF disease, and identify ECG differences from sarcomeric HCM.

Methods

Sixty-two consecutive patients (27 males, mean age: 62±16 years) with definite diagnosis of AF disease from 2 Italian centres were evaluated for ECG analysis and divided in 2 groups, according to the presence (Group A, N=39) or the absence (Group B, N=26) of cardiac involvement [hypertrophy detected at echocardiogram or cardiac magnetic resonance (CMR)]. All ECGs were analysed by 2 independent investigators. For Group A, when CMR was performed, a correlation between CMR and ECG was assessed. Patients with cardiac involvement were matched with 78 sarcomeric HCM patients according to sex, age and septal wall thickness on echocardiogram.

Results

Two AF patients out 39 with cardiac involvement (5%) had normal ECG. Short PR and I degree atrio-ventricular (AV) block were both reported in 6 (15%) cases. Twenty-six (67%) patients showed left ventricular hypertrophy and the majority (85%) had abnormal repolarization. CMR was performed in 22 patients (56%); the 11 (50%) patients with replacement fibrosis had a higher mean Sokolow-Lyon score (4.1±1.8 vs 2.9±1.0 mV; p=0.05), more frequent ST segment depression (82 vs 27%; p=0.03) and negative T waves (91 vs 36%; p=0.027; sensitivity: 90%; specificity: 63%), compared with the 11 without replacement fibrosis.

When compared with sarcomeric HCM, AF patients with cardiac involvement had a significantly wider QRS (120±30 vs 100±16 msec; p<0.0001), a higher frequency of right bundle branch block (RBBB) (18 vs 3%; p=0.01), ST segment depression (54 vs 20%; p<0.0001) and negative T waves (72 vs 46%; p=0.01), typically in the inferior leads (44 vs 14%; p<0.0001). No significant differences in terms of pseudo-necrosis and QRS voltages were found.

Among Group B AF patients (26, mean age: 36±12 years), 4 had short PR and 5 incomplete RBBB. Four had an abnormal ECG (1 left atrial enlargement, 2 unspecific repolarization abnormalities, 1 Sokolow score of 3.5 mV).

Conclusions

Standard ECG can detect cardiac involvement in AF disease. A good correlation was reported between repolarization abnormalities and replacement fibrosis on CMR. Wide QRS and RBBB were more frequent among AF patients compared to age-sex-matched sarcomeric HCM ones, probably due to the different aetiology of the diseases (infiltrative disease vs pure hypertrophy).

Twenty-Year Outcome After Mitral Repair Versus Replacement for Severe Degenerative Mitral Regurgitation

Background:

Mitral valve (MV) repair is preferred over replacement in clinical guidelines and is an important determinant of the indication for surgery in degenerative mitral regurgitation. However, the level of evidence supporting current recommendations is low, and recent data cast doubts on its validity in the current era. Accordingly, the aim of the present study was to analyze very long-term outcome after MV repair and replacement for degenerative mitral regurgitation with a flail leaflet.

Methods:

MIDA (Mitral Regurgitation International Database) is a multicenter registry enrolling patients with degenerative mitral regurgitation with a flail leaflet in 6 tertiary European and US centers. We analyzed the outcome after MV repair (n=1709) and replacement (n=213) overall, by propensity score matching, and by inverse probability-of-treatment weighting.

Results:

At baseline, patients undergoing MV repair were younger, had more comorbidities, and were more likely to present with a posterior leaflet prolapse than those undergoing MV replacement. After propensity score matching and inverse probability-of-treatment weighting, the 2 treatments groups were balanced, and absolute standardized differences were usually <10%, indicating adequate match. Operative mortality (defined as a death occurring within 30 days from surgery or during the same hospitalization) was lower after MV repair than after replacement in both the entire population (1.3% versus 4.7%; P <0.001) and the propensity-matched population (0.2% versus 4.4%; P <0.001). During a mean follow-up of 9.2 years, 552 deaths were observed, of which 207 were of cardiovascular origin. Twenty-year survival was better after MV repair than after MV replacement in both the entire population (46% versus 23%; P <0.001) and the matched population (41% versus 24%; P <0.001). Similar superiority of MV repair was obtained in patient subsets on the basis of age, sex, or any stratification criteria (all P <0.001). MV repair was also associated with reduced incidence of reoperations and valve-related complications.

Conclusions:

Among patients with degenerative mitral regurgitation with a flail leaflet referred to mitral surgery, MV repair was associated with lower operative mortality, better long-term survival, and fewer valve-related complications compared with MV replacement.

Wide spectrum of presentation and variable outcomes of isolated left ventricular non-compaction

OBJECTIVES

To investigate diagnostic routes, echocardiographic substrates, outcomes and prognostic factors in patients with isolated ventricular non-compaction (IVNC) identified by echocardiographic laboratories with referral from specialists and primary care physicians.

PATIENTS AND DESIGN

Since 1991, all patients with suspected IVNC were flagged and followed up on dedicated databases. Patients were divided into symptom-based and non-symptom-based diagnostic subgroups.

RESULTS

65 eligible patients were followed up for 6-193 months (mean 46 (SD 44). In 53 (82%) patients, IVNC was associated with variable degrees of left ventricular (LV) dilatation and hypokinesia, and in the remaining 12 (18%) LV volumes were normal. Diagnosis was symptom based in 48 (74%) and non-symptom based in 17 (26%) (familial referral in 10). The non-symptom-based subgroup was characterised by younger age, lower prevalence of ECG abnormalities, better systolic function and lower left atrial size, whereas the extent of non-compaction was not different. No major cardiovascular events occurred in the non-symptom-based group, whereas 15 of 48 (31%) symptomatically diagnosed patients experienced cardiovascular death or heart transplantation (p = 0.01, Kaplan-Meier analysis). Independent predictors of cardiovascular death or heart transplantation were New York Heart Association class III-IV, sustained ventricular arrhythmias and left atrial size.

CONCLUSIONS

IVNC is associated with a broad spectrum of clinical and pathophysiological findings, and the overall natural history and prognosis may be better than previously thought. Adult patients with incidental or familial discovery of IVNC have an encouraging outlook, whereas those who have symptoms of heart failure, a history of sustained ventricular tachycardia or an enlarged left atrium have an unstable course and more severe prognosis.

Automated morphometric analysis in peripheral neuropathies

We describe a three-step algorithm for the morphometric analysis of color images of nerve specimens, currently used in the diagnosis of peripheral neuropathies. The algorithm first segments the images by applying a clustering method in the color space. It then identifies and eliminates irrelevant regions and, in the final step, calculates the diagnostic parameters required for clinical analysis. The results obtained on 25 images are reported and compared with corresponding measurements made by neurologists.