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

The Rare Condition of Left Ventricular Non-Compaction and Reverse Remodeling

Left ventricular non-compaction (LVNC) is a rare disease defined by morphological criteria, consisting of a two-layered ventricular wall, a thin compacted epicardial layer, and a thick hyper-trabeculated myocardium layer with deep recesses. Controversies still exist regarding whether it is a distinct cardiomyopathy (CM) or a morphological trait of different conditions. This review analyzes data from the literature regarding diagnosis, treatment, and prognosis in LVNC and the current knowledge regarding reverse remodeling in this form of CM. Furthermore, for clear exemplification, we report a case of a 41-year-old male who presented symptoms of heart failure (HF). LVNC CM was suspected at the time of transthoracic echocardiography and was subsequently confirmed upon cardiac magnetic resonance imaging. A favorable remodeling and clinical outcome were registered after including an angiotensin receptor neprilysin inhibitor in the HF treatment. LVNC remains a heterogenous CM, and although a favorable outcome is not commonly encountered, some patients respond well to therapy.

Prognosis and subtype analysis of left ventricular noncompaction in adults: A retrospective multicenter study

BACKGROUND

Left ventricular noncompaction (LVNC) is a heterogeneous myocardial disorder with an uncertain prognosis. There was a lack of studies on LVNC subtypes at present. This study sought to identify the prognosis of the overall population of LVNC and to describe the distribution of different subtypes and compare their prognosis.

HYPOTHESIS

Patients with different subtypes of LVNC may have different prognoses.

METHODS

Patients who fulfilled the Jenni criteria and/or Petersen criteria were included. Major adverse cardiovascular events (MACE) were defined as a combination of heart failure (HF) hospitalization and all-cause mortality.

RESULTS

A total of 200 patients from four hospitals were included. The mean age at diagnosis was 48.2 years, and 61.5% of the patients were male. Left ventricular ejection fraction (LVEF) < 50% was present in 54% of the patients. Over a mean retrospective time period of 22.2 months, 47 (23.5%) patients experienced MACE. Age (hazard ratio [HR] 1.03; 95% confidence interval [CI] 1.01-1.06; p = .004), LVEF < 50% (HR 2.32; 95% CI 1.09-4.91; p = .028) and ventricular tachycardia/ventricular fibrillation (HR 2.17; 95% CI 1.08-4.37; p = .03) were significantly associated with the risk of MACE. The most common subtype was dilated LVNC (51.3%), followed by benign LVNC (21.3%) and LVNC with arrhythmias (10.5%). Patients with dilated LVNC had significantly increased cumulative incidence of MACE, HF hospitalization, and all-cause mortality (p < .05).

CONCLUSIONS

Age, LVEF < 50%, and ventricular tachycardia/ventricular fibrillation were independent risk factors for prognosis of LVNC. The most common subtype was dilated LVNC, which had a worse prognosis.

The use of 2-D speckle tracking echocardiography in assessing adolescent athletes with left ventricular hypertrabeculation meeting the criteria for left ventricular non-compaction cardiomyopathy

BACKGROUND

Current echocardiographic criteria cannot accurately differentiate exercise induced left ventricular (LV) hypertrabeculation in athletes from LV non-compaction cardiomyopathy (LVNC). This study aims to evaluate the role of speckle tracking echocardiography (STE) in characterising LV myocardial mechanics in healthy adolescent athletes with and without LVNC echocardiographic criteria.

METHODS

Adolescent athletes evaluated at three sports academies between 2014 and 2019 were considered for this observational study. Those meeting the Jenni criteria for LVNC (end-systolic non-compacted/compacted myocardium ratio > 2 in any short axis segment) were considered LVNC+ and the rest LVNC-. Peak systolic LV longitudinal strain (S_l), circumferential strain (S_c), rotation (Rot), corresponding strain rates (SR_l/c) and segmental values were calculated and compared using a non-inferiority approach.

RESULTS

A total of 417 participants were included, mean age 14.5 ± 1.7 years, of which 6.5% were LVNC+ (n = 27). None of the athletes showed any additional LVNC clinical criteria. All average S_l, SR_l S_c, SR_c and Rot values were no worse in the LVNC+ group compared to LVNC- (p values range 0.0003-0.06), apart from apical SR_c (p = 0.2). All 54 segmental measurements (S_l/S_c SR_l/SR_c and Rot) had numerically comparable means in both LVNC+ and LVNC-, of which 69% were also statistically non-inferior.

CONCLUSIONS

Among healthy adolescent athletes, 6.5% met the echocardiographic criteria for LVNC, but showed normal LV STE parameters, in contrast to available data on paediatric LVNC describing abnormal myocardial function. STE could better characterise the myocardial mechanics of athletes with LV hypertrabeculation, thus allowing the transition from structural to functional LVNC diagnosis, especially in suspected physiological remodelling.

Prognostic factors associated with left ventricular non-compaction: A PRISMA-compliant meta-analysis

BACKGROUND

Left ventricular non-compaction (LVNC) is a rare disease with a poor prognosis. Efforts to improve prognosis are limited by the quality and scope of the available evidence on prognostic factors.

METHODS

Pubmed, Embase, China National Knowledge Infrastructure, Cochrane Library, Wanfang, and Baidu Scholar were searched and all relevant studies that examined factors related to LVNC prognosis, published before January 2021, were retrieved. Study quality evaluation and data extraction were independently completed by two authors. Statistical analyses were performed using STATA 15.0 software.

RESULTS

A total of 20 cohort studies were included in this study, with a total of 1910 patients. The results of the meta-analysis are as follows: New York Heart Function Association (NYHA) class III/IV (hazard ratio [HR] = 3.93, 95% confidence interval [CI]: 1.66-9.29), (NT-proBNP) increased (HR = 1.98, 95% CI: 1.10-3.58), left ventricular ejection fraction (LVEF) decreased (HR = 1.04, 95% CI: 1.03-1.06), left ventricular end-diastolic diameter (LVEDD) increased (HR = 1.03, 95% CI: 1.01-1.06) was an independent poor prognostic factor, and body mass index (HR = 0.80, 95% CI: 0.64-0.98) was an independent protective factor. Creatinine (CR) level (HR = 1.09, 95% CI: 0.95-1.25) and late gadolinium-enhanced (LGE) imaging (HR = 3.1, 95% CI: 0.85-11.31) has no statistical significance in the prognosis of LVNC.

CONCLUSION

In LVNC patients, NYHA class III/IV, elevated N-terminal pro-brain natriuretic peptide (NT-proBNP) levels, decreased LVEF, and increased LVEDD may lead to poor prognosis, and increased body mass index may improve the prognosis of LVNC. Further clinical research with large sample sizes and long-term follow-ups should be conducted.

PROSPERO REGISTRATION NUMBER

42020152706.

Predictors of fatal arrhythmic events in patients with non-compaction cardiomyopathy: a systematic review

Left ventricular non-compaction cardiomyopathy (LVNC) is a congenital heart disease with autosomal dominant inheritance. This review aims to summarize the existing data about the predictors of fatal arrhythmias in patients with LVNC. Medline and Cochrane library databases were searched from inception to November 2021 for articles on LVNC. The reference lists of the relevant research studies as well as the relevant review studies and meta-analyses were also searched. Clinical symptoms and electrocardiogram findings such as left bundle branch block are significantly associated with ventricular arrhythmias. Other non-invasive tools such as Holter monitoring, echocardiography, and cardiac magnetic resonance (CMR) can provide additional value for risk stratification. CMR-derived left and right ventricular ejection fraction, left ventricular end-diastolic diameter, late gadolinium enhancement, and non-compacted to compacted myocardium ratio are predictive of ventricular arrhythmias. An electrophysiological study can provide additional prognostic data in patients with LVNC who are at moderate risk of ventricular arrhythmias. Risk stratification of LVNC patients with no prior history of a fatal arrhythmic event remains challenging. Symptoms assessment, electrocardiogram, Holter monitoring, and cardiac imaging should be performed on every patient, while an electrophysiological study should be performed for moderate-risk patients. Large cohort studies are needed for the construction of score models for arrhythmic risk stratification purposes.

Left Ventricular Non-Compaction Spectrum in Adults and Children: From a Morphological Trait to a Structural Muscular Disease

Left ventricular non-compaction (LVNC) is an extremely heterogeneous disorder with a highly variable clinical presentation, morphologic appearance at imaging testing, and prognosis. It is still unclear whether LVNC should be classified as a separate cardiomyopathy or if it is a mere morphological trait shared by many phenotypically distinct cardiomyopathies. Moreover, the hypertrabeculated phenotype may be reversible in some cases, possibly reflecting the left ventricular physiological response of the cardiac muscle to chronic overload. The current diagnostic criteria have several limitations, leaving many patients in a grey area. Here, we review the available literature on LVNC in order to provide an overview of the current knowledge on this complex disorder.

Cardiac geometry, function and mechanics in left ventricular non-compaction cardiomyopathy with preserved ejection fraction

BACKGROUND

Left ventricular non-compaction (LVNC) cardiomyopathy in adults has primarily been studied with a phenotypic expression of low ejection fraction (EF) and dilated cardiomyopathy; however, data on LVNC with preserved EF is scarce. The present study aimed to evaluate cardiac geometry and mechanics in LVNC patients with preserved EF.

METHODS

A retrospective cohort study of patients diagnosed with LVNC and a preserved EF between 2008 and 2019 was performed. LVNC was defined according to the presence of established transthoracic 2D echocardiographic (TTE) criteria as follows: (1) prominent LV trabeculations with deep recesses; (2) bi-layered myocardial appearance; and, (3) systolic non-compacted:compacted ratio≥ 2. Subjects were matched 1:1 to controls without LVNC referred for routine TTE. Geometric, functional and mechanics parameters were analyzed in the two cohorts using 2D and speckle-tracking TTE.

RESULTS

Seventeen patients with LVNC and preserved EF were identified. Compared with controls, patients with LVNC had similar LV systolic function and chamber dimensions, but a larger mass and relative wall thickness, and more abnormal LV geometry (76% vs. 18%, p = 0.002), LA remodeling, and pulmonary hypertension. Global longitudinal strain was significantly decreased (-15.4 ± 3.2 vs. -18.9 ± 2.8%, p =  < 0.01) and the prevalence of rigid body rotation was significantly increased (57% vs. 14%, p = 0.05) in the LVNC population. The peak twist values were comparable in both cohorts.

CONCLUSIONS

Impaired LV geometry and longitudinal mechanics, as well as increased myocardial stiffness as expressed by rigid body rotation, characterize LVNC with preserved EF when compared with controls.

Hypertrabeculation; a phenotype with Heterogeneous etiology

Left ventricular hypertrabeculation (LVHT) is a phenotype with multiple etiologies and variable clinical presentation and significance. It is characterized by a 2-layer myocardium with an enlarged trabecular layer and a thinner compacted layer. The prevalence has been increasing due to advances in cardiac imaging. Initial attention was focused on the congenital noncompaction syndrome, and the presence of LVHT was always attributed to this etiology. However, due to the lack of consensus diagnostic criteria, LVHT has now been reported in a broad spectrum of cardiomyopathies, congenital heart diseases, monogenetic disorders, neuromuscular diseases, and even healthy individuals. LVHT is often associated with systolic dysfunction, arrhythmias, and thromboembolic events. Given the etiologic heterogeneity, the prognosis and outcomes are primarily determined by comorbidities, and treatment is dictated by known guidelines. We present hypertrabeculation (HT) as a phenotype and discuss the varied landscape in the classification, etiology, diagnosis, and management of the condition.

Left ventricular mechanics and cardiovascular outcomes in non-compaction phenotype

AIMS

This study aims at understanding left ventricular (LV) mechanics of non-compaction (LVNC) phenotype using echocardiographic strain analysis and at assessing the association of functional parameters with cardiovascular (CV) outcomes.

METHODS AND RESULTS

Longitudinal (GLS) and circumferential strain (GCS) as well as rotation of the LV were analyzed in 55 LVNC patients and 55 matched controls. Cardiovascular outcomes were documented for a median follow-up duration of 6 years. GLS and GCS were impaired in LVNC. Similary, regional longitudinal and circumferential strain as well as twist were reduced. CV events occurred in 28 LVNC patients. Apical peak circumferential strain (APCS), peak systolic rotation of apical segments (APSR), and twist were strongly associated with events. This was independent of and incremental to LVEF and non-compacted to compacted myocardial thickness ratio (NC:C ratio). The association of twist with events was also independent of and slightly superior to GLS.

CONCLUSIONS

GLS, GCS, regional strain, and twist were impaired in LVNC. APCS, APSR, and twist exhibited strong association with CV events independent of and incremental to LVEF and NC:C ratio, and in case of twist even GLS. Thus, STE-derived parameters may complement the echocardiographic assessment of LVNC patients in clinical routine.

Association Between Left Ventricular Noncompaction and Vigorous Physical Activity

BACKGROUND

Left ventricular (LV) hypertrabeculation fulfilling noncompaction cardiomyopathy criteria has been detected in athletes. However, the association between LV noncompaction (LVNC) phenotype and vigorous physical activity (VPA) in the general population is disputed.

OBJECTIVES

The aim of this study was to assess the relationship between LVNC phenotype on cardiac magnetic resonance (CMR) imaging and accelerometer-measured physical activity (PA) in a cohort of middle-aged nonathlete participants in the PESA (Progression of Early Subclinical Atherosclerosis) study.

METHODS

In PESA participants (n = 4,184 subjects free of cardiovascular disease), PA was measured by waist-secured accelerometers. CMR was performed in 705 subjects (mean age 48 ± 4 years, 16% women). VPA was recorded as total minutes per week. The study population was divided into 6 groups: no VPA and 5 sex-specific quintiles of VPA rate (Q1 to Q5). The Petersen criterion for LVNC was evaluated in all subjects undergoing CMR. For participants meeting this criterion (noncompacted-to-compacted ratio ≥2.3), 3 more restrictive LVNC criteria were also evaluated (Jacquier, Grothoff, and Stacey).

RESULTS

LVNC phenotype prevalence according to the Petersen criterion was significantly higher among participants in the highest VPA quintile (Q5 = 30.5%) than in participants with no VPA (14.2%). The Jacquier and Grothoff criteria were also more frequently fulfilled in participants in the highest VPA quintile (Jacquier Q5 = 27.4% vs. no VPA = 12.8% and Grothoff Q5 = 15.8% vs. no VPA = 7.1%). The prevalence of the systolic Stacey LVNC criterion was low (3.6%) and did not differ significantly between no VPA and Q5.

CONCLUSIONS

In a community-based study, VPA was associated with a higher prevalence of CMR-detected LVNC phenotype according to diverse established criteria. The association between VPA and LVNC phenotype was independent of LV volumes. According to these data, vigorous recreational PA should be considered as a possible but not uncommon determinant of LV hypertrabeculation in asymptomatic subjects.

Long-Term Survival of Patients With Left Ventricular Noncompaction

Background

The prognosis of left ventricular noncompaction (LVNC) remains elusive despite its recognition as a clinical entity for >30 years. We sought to identify clinical and imaging characteristics and risk factors for mortality in patients with LVNC.

Methods and Results

339 adults with LVNC seen between 2000 and 2016 were identified. LVNC was defined as end‐systolic noncompacted to compacted myocardial ratio >2 (Jenni criteria) and end‐diastolic trough of trabeculation‐to‐epicardium (X):peak of trabeculation‐to‐epicardium (Y) ratio <0.5 (Chin criteria) by echocardiography; and end‐diastolic noncompacted:compacted ratio >2.3 (Petersen criteria) by magnetic resonance imaging. Median age was 47.4 years, and 46% of patients were female. Left ventricular ejection fraction <50% was present in 57% of patients and isolated apical noncompaction in 48%. During a median follow‐up of 6.3 years, 59 patients died. On multivariable Cox regression analysis, age (hazard ratio [HR] 1.04; 95% CI, 1.02–1.06), left ventricular ejection fraction <50% (HR, 2.37; 95% CI, 1.17–4.80), and noncompaction extending from the apex to the mid or basal segments (HR, 2.11; 95% CI, 1.21–3.68) were associated with all‐cause mortality. Compared with the expected survival for age‐ and sex‐matched US population, patients with LVNC had reduced overall survival (P<0.001). However, patients with LVNC with preserved left ventricular ejection fraction and patients with isolated apical noncompaction had similar survival to the general population.

Conclusions

Overall survival is reduced in patients with LVNC compared with the expected survival of age‐ and sex‐matched US population. However, survival rate in those with preserved left ventricular ejection fraction and isolated apical noncompaction was comparable with that of the general population.

Left Ventricular Noncompaction: Diagnostic Approach, Prognostic Evaluation, and Management Strategies

Left ventricular noncompaction cardiomyopathy is a heart disease with relevant potential complications including heart failure, life-threatening arrhythmias, and embolic events. In order to prevent adverse outcomes, it is crucial to appropriately recognize and manage this cardiomyopathy. In this paper, we report the main clinical presentations and imaging modalities used for diagnosis, including echocardiography and magnetic resonance imaging. We highlight the role of a comprehensive functional cardiac evaluation and the possible prognostic implications of both systolic and diastolic dysfunction. Furthermore, we summarize clinical factors and imaging findings which have prognostic significance. Finally, we discuss the main management strategies based on phenotypic expressions which are aimed at treating symptoms and preventing complications.

Intraventricular synchronism assessment by gated-SPECT myocardial perfusion imaging in cardiac resynchronization therapy. Does cardiomyopathy type influence results?

Purpose

To analyze the evolution post-cardiac resynchronization therapy (CRT) in left ventricular non-compaction (LVNC) cardiomyopathy (CM) patients compared to other types of CM, according to clinical and functional variables, by using gated-SPECT myocardial perfusion imaging (MPI).

Methods

Ninety-three patients (60 ± 11 years, 28% women) referred for pre-CRT assessment were studied and divided into three groups: 1 (non-ischemic CM with LVNC, 11 patients), 2 (ischemic CM, 28 patients), and 3 (non-ischemic CM, 53 patients). All were studied by a ^99mTc-MIBI gated-SPECT MPI at rest pre-CRT implantation and 6 ± 1 months after, including intraventricular dyssynchrony assessment by phase analysis. Quality of life was measured by the Minnesota Living with Heart Failure Questionnaire (MLHFQ).

Results

No differences in sex, atherosclerotic risk factors other than smoking habit, and MLHFQ results were found among groups. LVNC CM patients were younger, with greater QRS width and lower left ventricular ejection fraction (LVEF) at baseline, but the differences were not significant. No significant differences were found at baseline regarding ventricular function, although end-systolic volume was slightly higher in LVNC CM patients. Mean SRS was significantly higher (p < 0.0001) in ischemic patients (14.9) versus non-ischemic ones (8.7 in group 1 and 9 in group 2). At baseline, LVNC CM patients were significantly more dyssynchronous: Their phase standard deviation (PSD) was higher (89.5° ± 14.2°) versus groups 2 (65.2° ± 23.3°) and 3 (69.7° ± 21.7°), p = 0.007. Although the quality of life significantly improved in all groups, non-ischemic patients (with or without LVNC) showed a higher LVEF increase and volumes reduction at 6 months post-CRT. Dyssynchrony reduced post-CRT in all groups. Nevertheless, those more dyssynchronous at baseline (LVNC CM) exhibited the most significant intraventricular synchronism improvement: PSD was reduced from 89.5° ± 14.2° at baseline to 63.7° ± 20.5° post-CRT (p = 0.028). Six months post-CRT, 89% of patients were responders: 11 (100%) of those with LVNC CM, 25 (86%) of those with ischemic CM, and 47 (89%) of patients with non-ischemic CM. No patient with LVNC CM had adverse events during the follow-up.

Conclusion

CRT contributes to a marked improvement in non-ischemic CM patients with non-compaction myocardium. Phase analysis in gated-SPECT MPI is a valuable tool to assess the response to CRT.

Left Ventricular Noncompaction Is More Prevalent in Ventricular Septal Defect Than Other Congenital Heart Defects: A Morphological Study

Left ventricular noncompaction (LVNC) is a condition characterized by prominent ventricular trabeculae and deep intertrabecular recesses and has been described as a possible substrate for arrhythmias, thromboembolism, and heart failure. Herein, we explored the prevalence of LVNC morphology among hearts with congenital heart defects (CHD). We examined 259 postnatal hearts with one of the following CHD: isolated ventricular septal defect (VSD); isolated atrial septal defect (ASD); atrioventricular septal defect (AVSD); transposition of the great arteries (TGA); isomerism of the atrial appendages (ISOM); Ebstein’s malformation (EB); Tetralogy of Fallot (TF). Eleven hearts from children who died of non-cardiovascular causes were used as controls. The thickness of the compacted and non-compacted left ventricular myocardial wall was determined and the specimens classified as presenting or not LVNC morphology according to three criteria, as proposed by Chin, Jenni, and Petersen. Normal hearts did not present LVNC, but the CHD group presented different percentages of LVNC in at least one diagnostic criterium. The prevalence of LVNC was respectively, according to Chin’s, Jenni´s and Petersen´s methods: for VSD—54.2%, 35.4%, and 12.5%; ASD—8.3%, 8.3%, and 8.3%; AVSD—2.9%, 2.9%, and 0.0%; TGA—22.6%, 17%, and 5.7%; ISOM—7.1%, 7.1%, and 7.1%; EB—28.6%, 9.5%, and 0.0%; TF—5.9%. 2.9%, and 2.9%. VSD hearts showed a significantly greater risk of presenting LVNC when compared to controls (Chin and Jenni criteria). No other CHD presented similar risk. Current results show some agreement with previous studies, such as LVNC morphology being more prevalent in VSDs. Nonetheless, this is a morphological study and cannot be correlated with symptoms or severity of the CHD.

Antithrombotic Treatment in Cardiomyopathies

:

Cardiomyopathies are a heterogeneous group of heart muscle diseases and important cause of heart failure with reduced or preserved ejection fraction. Although there is an increasing body of evidence on the incidence, pathophysiology, and natural history of heart failure (HF) in cardiomyopathies, certain aspects of the therapeutic strategies remain unclear. More particularly, there is no consensus if to whether antithrombotic therapy has a favorable risk: benefit ratio in reducing thromboembolic event rate in patients with cardiomyopathies without suffering from primary valvular disease or atrial fibrillation. Although the observational data on increased venous thromboembolic risk are supported by multiple pathophysiological mechanisms, the role of antithrombotic therapy in these patients remains unclear. This review article provides an overview of epidemiologic, pathophysiologic, clinical, and therapeutic data for the prevention of thromboembolism in heart failure due to cardiomyopathies.

Different Manifestations in Familial Isolated Left Ventricular Non-compaction: Two Case Reports and Literature Review

Left ventricular non-compaction (LVNC) is a form of cardiomyopathy characterized by prominent trabeculae and deep intertrabecular recesses which form a distinct "non-compacted" layer in the myocardium. It results from intrauterine arrest of the compaction process of the left ventricular myocardium. Clinical manifestations vary from asymptomatic to heart failure (HF), arrhythmias, or thromboembolic events. We present a case of mother and son diagnosed with isolated LVNC (ILVNC). A 4-years-old male patient, diagnosed at 3 months with ILVNC, and NYHA functional class IV HF, was admitted to the Emergency Institute for Cardiovascular Diseases and Transplantation of Targu Mures, Romania, for cardiologic reevaluation, and diagnosis confirmation. ILVNC was confirmed using echocardiography, revealing a non-compaction to compaction (NC/C) ratio of > 2.7. His evolution was stationary until the age of 8 years, when severe pneumonia caused hemodynamic decompensation, and he was listed for heart transplantation (HT). The patient underwent HT at the age of 11 years with favorable postoperative outcome. Meanwhile, a 22-years-old female patient, mother of the aforementioned patient, was also admitted to our institute due to severe fatigue, dyspnea, and recurrent palpitations with multiple implantable cardioverter defibrillator (ICD) shock delivery. Extensive medical history revealed that a presumptive ILVNC diagnosis was established when she was 11 years old. She was asymptomatic until 18 years old, when 3 months post-partum, she developed NYHA functional class III HF, and subsequently underwent ICD implantation. Her diagnosis was confirmed using multi-detector computed tomography angiography, which revealed a NC/C ratio of > 3.3. ICD adjustments were carried out with a favorable evolution under chronic drug therapy. The last evaluation, at 27 years old, revealed that she was in NYHA functional class II HF. In conclusion, ILVNC, even when familial, can present different clinical pictures and therefore requires different medical approaches.

Prognostic Significance of Left Ventricular Noncompaction: Systematic Review and Meta-Analysis of Observational Studies

BACKGROUND

Although left ventricular noncompaction (LVNC) has been associated with an increased risk of adverse cardiovascular events, the accurate incidence of cardiovascular morbidity and mortality is unknown. We, therefore, aimed to assess the incidence rate of LVNC-related cardiovascular events.

METHODS

We systematically searched observational studies reporting the adverse outcomes related to LVNC. The primary end point was cardiovascular mortality.

RESULTS

We identified 28 eligible studies enrolling 2501 LVNC patients (mean age, 46 years; male/female ratio, 1.7). After a median follow-up of 2.9 years, the pooled event rate for cardiovascular mortality was 1.92 (95% CI, 1.54-2.30) per 100 person-years. LVNC patients had a similar risk of cardiovascular mortality compared with a dilated cardiomyopathy control group (odds ratio, 1.10 [95% CI, 0.18-6.67]). The incidence rates of all-cause mortality, stroke and systemic emboli, heart failure admission, cardiac transplantation, ventricular arrhythmias, and cardiac device implantation were 2.16, 1.54, 3.53, 1.24, 2.17, and 2.66, respectively, per 100 person-years. Meta-regression and subgroup analyses revealed that left ventricular ejection fraction, not the extent of left ventricular trabeculation, had an important influence on the variability of incidence rates. The risks of thromboembolism and ventricular arrhythmias in LVNC patients were similar to dilated cardiomyopathy patients. However, LVNC patients had a higher incidence of heart failure hospitalization than dilated cardiomyopathy patients.

CONCLUSIONS

Patients with LVNC carry a similar cardiovascular risk when compared with dilated cardiomyopathy patients. Left ventricular ejection fraction-a conventional indicator of heart failure severity, not the extent of trabeculation-appears to be an important determinant of adverse outcomes in LVNC patients. Registration: https://www.crd.york.ac.uk/PROSPERO/ Unique identifier: CRD42018096313.

[Left ventricular non - compaction: contemporary view of genetic background, clinical course, diagnostic and treatment]

This review highlights and discusses recent advances in understanding left ventricular non - compaction (LVNC). Clinical profile, prognosis and even diagnosis are still a great challenge faced by the world. The population prevalence of left ventricular non - compaction remains unknown. High variability of clinical manifestations, genetic heterogenity with overlap of different phenotypes, variability of hereditary patterns suggests that LVNC seems to be rather an isolated trait or a part of phenotypic expression of different cardiac diseases or complex genetic syndromes.

Right ventricle and outcome in left ventricular non-compaction cardiomyopathy

BACKGROUND

The risk of adverse events in patients with left ventricular non-compaction cardiomyopathy (LVNC) is substantial. Information on prognostic factors, however, is limited. This study was designed to assess the prognostic value of right ventricular (RV) size and function in LVNC patients.

METHODS

Cox regression analyses were used to determine the association of indexed RV end-diastolic area (RV-EDAI), indexed end-diastolic diameter (RV-EDDI), fractional area change (FAC), and tricuspid annular systolic excursion (TAPSE) with the occurrence of death or heart transplantation (composite endpoint).

RESULTS

Out of 127 patients (53.2 ± 17.8 years; 61% males, median follow-up time was 7.7 years), 17 patients reached the endpoint. In a univariate analysis, RV-EDAI was the strongest predictor of outcome [HR 1.48 (1.24-1.77) per cm²/m²; p < 0.0001]. FAC was predictive as well [HR 1.44 (1.16-1.83) per 5% decrease; p = 0.0009], while TAPSE was not (p=ns). RV-EDAI remained an independent predictor in a bivariable analysis with indexed left ventricular ED volume [HR 1.41 (1.18-1.70) per cm²/m²; p = 0.0002], while analysis of FAC and left ventricular ejection fraction demonstrated that FAC was not independent [HR 1.20 (0.98-1.52); per 5% decrease; p = 0.0721]. RV-EDAI 11.5 cm²/m² was the best cut-off value for separating patients in terms of outcome. Patients with RV-EDAI >11.5 cm²/m² had a survival rate of 18.5% over 12 years as compared to 93.8% in patients with RV-EDAI <11.5 cm²/m² (p < 0.0001).

CONCLUSION

Increased end-diastolic RV size and decreased systolic RV function are predictors of adverse outcome in patients with LVNC. Patients with RV-EDAI >11.5 cm²/m² exhibit a significantly lower survival than those <11.5 cm²/m².

Increased Left Ventricular Trabeculation Is Associated With Increased B-Type Natriuretic Peptide Levels and Impaired Outcomes in Nonischemic Cardiomyopathy

BACKGROUND

The clinical significance of left ventricular (LV) trabeculation remains unknown in cardiomyopathies. B-Type natriuretic peptide (BNP) strongly reflects LV end-diastolic wall stress and is a useful prognostic marker of cardiovascular diseases. The enhanced identification of LV trabeculae (T) with the use of cardiac magnetic resonance and the evaluation of its relationship with BNP may elucidate the biologic significance and clinical impact of trabeculation in patients with nonischemic cardiomyopathy (NICM).

METHODS

The LV volume and mass of 515 patients with NICM and 36 control subjects were analyzed with the use of a steady-state free precession sequence, and individual T mass was planimetred. Major adverse cardiac events (MACE) were assessed.

RESULTS

T mass index correlated with LV end-diastolic volume index (EDVI), LV mass index, and papillary muscle mass index (all P < 0.001). Also, T mass index was positively correlated with BNP level (R = 0.381; P < 0.001) and was an independent determinant of BNP after adjusting for age, sex, body mass index (BMI), etiology, LV ejection fraction, and LV EDVI (P < 0.001). Kaplan-Meier analysis during a median follow-up of 17.3 months showed that higher T mass index and increased BNP level correlated with MACE. On multivariate analysis, T mass index (P = 0.031) and BNP (P < 0.001) remained associated with poor outcomes when combined with age, sex, BMI, and etiology.

CONCLUSIONS

Increased LV trabeculation was associated with LV dysfunction/remodelling and impaired outcomes in NICM of various etiologies. This may support the biologic significance of LV trabeculation and could be attributed to its association with BNP through LV wall stress.

A Case of Isolated Left Ventricular Non-Compaction Cardiomyopathy in a HIV Patient Presenting With Acute Heart Failure

The etiology of cardiomyopathy in a HIV patient is multifactorial. Identifying the etiology of cardiomyopathy in a HIV patient needs extensive evaluation. Common causes include ischemic cardiomyopathy, myocarditis due to viral infections and opportunistic infections, cocaine abuse, alcoholic heart disease, drug toxicity or due to nutritional deficiencies. However, in a number of cases the etiology is unknown. We report a case of 36-year-old African American man with history of HIV who presented with acute heart failure due to left ventricular non-compaction (LVNC). Transthoracic and transesophageal echocardiogram showed significant left ventricular trabeculations and blood flow in deep recesses. Endomyocardial biopsy was suggestive of LVNC. He underwent left ventricular assist device implantation for destination therapy and subsequently cardiac transplantation. The diagnosis of LVNC is often made by echocardiogram. As LVNC could be a normal variant, a comprehensive diagnostic assessment including multimodality imaging, a systematic screening of first degree relatives, and a comprehensive clinical and genetic assessment by a multidisciplinary team may be needed to arrive at the diagnosis. Early diagnosis and timely intervention may reduce the risk of premature death in these young patients.

[Left ventricular non-compaction: What should be known!]

Isolated non-compaction of the left ventricle (NCVG) is a rare congenital cardiomyopathy resulting from the shutdown of normal embryogenesis of the myocardium. Its main feature is the existence of many deep heart-related ventricular trabeculations, generally located at the level of the apex of the left ventricle. Diagnosis is based on echocardiography and magnetic resonance imaging (MRI), and may be difficult in the atypical forms. The clinical presentation and the prognosis are very variable. Familial forms are not rare, ordering a family screening.

Meta-Analysis of the Prognostic Role of Late Gadolinium Enhancement and Global Systolic Impairment in Left Ventricular Noncompaction

OBJECTIVES

The objective of this meta-analysis was to assess the predictive value of late gadolinium enhancement (LGE) and global systolic impairment for future major adverse cardiovascular events in left ventricular noncompaction (LVNC).

BACKGROUND

The prognosis of patients with LVNC, with and without left ventricular dysfunction and LGE, is still unclear.

METHODS

A systematic review of published research and a meta-analysis reporting a combined endpoint of hard (cardiac death, sudden cardiac death, appropriate defibrillator firing, resuscitated cardiac arrest, cardiac transplantation, assist device implantation) and minor (heart failure hospitalization and thromboembolic events) events was performed.

RESULTS

Four studies with 574 patients with LVNC and 677 with no LVNC and an average follow-up duration of 5.2 years were analyzed. In patients with LVNC, LGE was associated with the combined endpoint (pooled odds ratio: 4.9; 95% confidence interval: 1.63 to 14.6; p = 0.005) and cardiac death (pooled odds ratio: 9.8; 95% confidence interval: 2.44 to 39.5; p < 0.001). Preserved left ventricular systolic function was found in 183 patients with LVNC: 25 with positive LGE and 158 with negative LGE. In LVNC with preserved ejection fraction, positive LGE was associated with hard cardiac events (odds ratio: 6.1; 95% confidence interval: 2.1 to 17.5; p < 0.001). No hard cardiac events were recorded in patients with LVNC, preserved ejection fraction, and negative LGE.

CONCLUSIONS

Patients with LVNC but without LGE have a better prognosis than those with LGE. When LGE is negative and global systolic function is preserved, no hard cardiac events are to be expected. Currently available criteria allow diagnosis of LVNC, but to further define the presence and prognostic significance of the disease, LGE and/or global systolic impairment must be considered for better risk stratification.

Left ventricular noncompaction and orthodromic atrioventricular tachycardia observed in a patient with neurofibromatosis type 1

Isolated left ventricular noncompaction (LVNC) was described for the first time in 1984. It is a rare congenital disease, characterized by prominent trabecular meshwork pattern and deep intertrabecular recesses, communicated with the left ventricular chamber. Clinical presentation varies from asymptomatic patients, to those developing supraventricular and ventricular arrhythmias, thromboembolism, heart failure and sudden cardiac death. We present an unusual case, where the patient with Neurofibromatosis type 1 presented with a wide complex orthodromic atrioventricular reentrant tachycardia (AVRT) and a diagnosis of left posterior paraseptal accessory pathway in association with LVNC.

Anticoagulation Therapy in Specific Cardiomyopathies: Isolated Left Ventricular Noncompaction and Peripartum Cardiomyopathy

In 2 distinct entities, left ventricular noncompaction (LVNC) and peripartum cardiomyopathy (PPCM), routine anticoagulation therapy is often used in current practices. However, our systematic review showed that LVNC itself was not associated with the increase in thromboembolism event rates and therapeutic anticoagulation therapy should not be considered only for LVNC, unless there is risk factor for thromboembolism. Current literature justifies prophylactic therapeutic anticoagulation in LVNC with low left ventricular ejection fraction (EF < 40%) and/or atrial fibrillation. Although not specifically studied, the presence of intracardiac thrombi by echocardiography or other imaging studies should also prompt anticoagulation therapy. There is limited evidence available for the use of anticoagulation in patients with PPCM, but our systematic review showed that anticoagulation should be recommended only for patients with PPCM especially with an EF < 35% until EF is recovered, as well as for patients with PPCM treated with bromocriptine.

Left ventricular hypertrabeculation/noncompaction, cardiac phenotype, and neuromuscular disorders

BACKGROUND

The prognosis of patients with left ventricular hypertrabeculation/noncompaction (LVHT) and its association with neuromuscular disorders (NMDs) is a controversial topic. The aim of this study was to assess whether the prognosis of LVHT patients is dependent on cardiac phenotype and the presence of NMDs.

METHODS

Consecutive patients who were diagnosed with LVHT between 1995 and 2016 were included in the study. Cardiac phenotype was classified according to the recommendations of the European Society of Cardiology as: "dilated" if the left ventricular end-diastolic diameter (LVEDD) was >57 mm and left ventricular fractional shortening (FS) was ≤25%; "hypertrophic" if LVEDD was ≤57 mm, FS > 25%, and left ventricular posterior wall (LVPWT) and interventricular septal thickness (IVST) were both >13 mm; "intermediate" if LVEDD was >57 mm and FS > 25% or if LVEDD was ≤57 mm and FS ≤ 25%; and "normal" if LVEDD was ≤57 mm, FS > 25%, and IVST and LVPWT ≤ 13 mm. Therapy was carried out by the treating physicians.

RESULTS

LVHT was diagnosed in 273 patients (80 females, 53 ± 16 years). The phenotype was assessed as dilated in 46%, hypertrophic in 8%, intermediate in 17%, and normal in 29% of the patients. Of these patients, 72% underwent neurological examinations, and an NMD was found in 76%. Over a period of 7.4 years (±5.7), 84 patients died and six underwent cardiac transplantation. The highest mortality rate was observed in the dilated and the lowest in the hypertrophic cardiac phenotype groups. Among the dilated phenotype, mortality was higher in patients with than without NMDs.

CONCLUSION

Patients with LVHT and dilated cardiac phenotype have a worse prognosis than patients with a hypertrophic or intermediate/normal cardiac phenotype, especially if they suffer from NMDs.

Supplementary Diagnostic Landmarks of Left Ventricular Non-Compaction on Magnetic Resonance Imaging

PURPOSE

Diagnostic criteria for left ventricular non-compaction (LVNC) are still a matter of dispute. The aim of our present study was to test the diagnostic value of two novel diagnostic cardiac magnetic resonance (CMR) parameters: proof of non-compact (NC) myocardium blood flow using T2 sequences and changes in geometry of the left ventricle.

MATERIALS AND METHODS

The study included cases with LVNC and controls, from a data base formed in a period of 3.5 years (n=1890 exams), in which CMR protocol included T2 sequences. Measurement of perpendicular maximal and minimal end diastolic dimensions in the region with NC myocardium from short axis plane was recorded, and calculated as a ratio (MaxMinEDDR), while flow through trabecula was proven by intracavital T2-weighted hyperintensity (ICT2HI). LVNC diagnosis met the following three criteria: thickening of compact (C) layer, NC:C>2.3:1 and NC>20%LV.

RESULTS

The study included 200 patients; 71 with LVNC (35.5%; i.e., 3.76% of CMRs) and 129 (64.5%) controls. MaxMinEDDR in patients with LVNC was significantly different from that in controls (1.17±0.08 vs. 1.06±0.04, respectively; p<0.001). MaxMinEDDR >1.10 had sensitivity of 91.6% [95% confidence intervals (CI) 82.5-96.8], specificity of 85.3% (95% CI 78.0-90.0), and area under curve (AUC) 0.919 (95% CI 0.872-0.953; p<0.001) for LVNC. Existence of ICT2HI had sensitivity of 100.0% (95% CI 94.9-100.0), specificity of 91.5% (95% CI 85.3-95.7), and AUC 0.957 (95% CI 0.919-0.981; p<0.001) for LVNC.

CONCLUSION

Two additional diagnostic parameters for LVNC were identified in this study. ICT2HI and geometric eccentricity of the ventricle both had relatively high sensitivity and specificity for diagnosing LVNC.

Auxiliary diagnostic potential of ventricle geometry and late gadolinium enhancement in left ventricular non-compaction; non-randomized case control study

Background

There are still ambiguities existing in regard to left ventricular non-compaction (LVNC) diagnostic imaging. The aim of our study was to analyze diagnostic potential of late gadolinium enhancement (LGE) and ventricle geometry in patients with LVNC and controls.

Methods

Data on cardiac magnetic resonance imaging (CMR) studies for LVNC were reassessed from the hospital’s database (3.75 years; n=1975 exams). Matching sample of controls included cases with no structural heart disease, hypertrophic or dilative cardiomyopathy, arrhythmogenic right ventricular dysplasia or subacute myocarditis. Eccentricity of the left ventricle was measured at end diastole in the region with pronounced NC and maximal to minimal ratio (MaxMinEDDR) was calculated.

Results

Study included 255 patients referred for CMR, 100 (39.2%) with LVNC (prevalence in the studied period 5.01%) and 155 (60.8%) controls. Existing LGE had sensitivity of 52.5% (95%-CI:42.3–62.5), specificity of 80.4% (95%-CI:73.2–86.5) for LVNC, area under curve (AUC) 0.664 (95%-CI:0.603–0.722);p<0.001. MaxMinEDDR>1.10 had sensitivity of 95.0% (95%-CI:88.7–98.4), specificity of 82.6% (95%-CI: 75.7–88.2) for LVNC, AUC 0.917 (95%-CI:0.876–0.948); p<0.001. LGE correlated with Max-Min-EDD-R (Rho=0.130; p=0.038) and there was significant difference in ROC analysis ΔAUC0.244 (95%-CI:0.175–0.314); p<0.001. LGE also correlated negatively with stroke volume and systolic function (both p<0.05, respectively).

Conclusions

LGE was found to be frequently expressed in patients with LVNC, but without sufficient power to be used as a discriminative diagnostic parameter. Both LGE and eccentricity of the left ventricle were found to be relatively solid diagnostic landmarks of complex infrastructural and functional changes within the failing heart.

Non compaction cardiomyopathy: Review of a controversial entity

Non-compaction cardiomyopathy is a heterogeneous and complex entity concerning which there are still many doubts to be resolved. While the American Heart Association includes it among genetic cardiomyopathies, the European Society of Cardiology treats it as an unclassified cardiomyopathy. It may present in a sporadic or familial form, isolated or associated with other heart diseases, affecting only the left ventricle or both and can sometimes appear as a mixed phenotype in patients with other cardiomyopathies. Different forms of clinical presentation are also associated with its different morphological manifestations, and even non-compaction of the left ventricle may be triggered by other physiological or pathological processes. The purpose of this review is an update of this entity and its controversies.

Spectrum of Cardiac Arrhythmias in Isolated Ventricular Non-Compaction

A wide spectrum of cardiac arrhythmias has been observed in patients with isolated ventricular non-compaction, which is defined by hypertrabeculated ventricular myocardium with deep intertrabecular recesses, in the absence of concomitant congenital heart disease. In this genetically diverse phenotype, the development of fibrosis contributes to an arrhythmogenic substrate underlying atrioventricular conduction diseases, supraventricular tachycardias and ventricular tachycardias. Within this spectrum, monomorphic ventricular tachycardia is the most frequently observed arrhythmia, and this prevalence has important implications for sudden cardiac death risk.

Left Ventricular Noncompaction Cardiomyopathy in Pediatric Patients: A Case Series of a Clinically Heterogeneous Disease

Left ventricular noncompaction is a rare form of cardiomyopathy, which results from multiple trabeculations in the left ventricular myocardium. The clinical presentation is highly variable, and spectrum includes asymptomatic patients diagnosed during family screening on one end to patients with depressed systolic function, heart failure, thromboembolic complications, and cardiac arrhythmias on the other (Kim et al in J Am Coll Cardiol 53: 2009, 2009). Further, the progression of the condition is highly variable. Hence, these patients require close follow-up, and management for each patient needs to be individualized and periodically reevaluated. Here, we present a series of five cases that have been followed in our practice and present our experience. A literature review of this rare form of congenital cardiomyopathy is also presented.

Long-Term Prognosis of Patients With Left Ventricular Noncompaction - Comparison Between Infantile and Juvenile Types

BACKGROUND

The natural history of left ventricular noncompaction (LVNC) is largely unsolved, so the aim of the present study was to clarify the clinical features and long-term prognosis of children with LVNC until adulthood.Methods and Results:We conducted a nationwide survey over 20 years and compared the clinical features, anatomical characteristics and long-term prognosis of 205 patients divided into 2 classifications: infantile type (diagnosed at <1 year of age: 108 cases) and juvenile type (diagnosed 1-15 years of age: 97 cases). Most patients diagnosed during infancy had heart failure (HF) at initial presentation (60.19%), while the majority of juvenile cases were asymptomatic (53.61%) but their event-free survival rate decreased gradually, because of later HF, thromboembolism and fatal arrhythmias. The initial LVEF was significantly lower in the infantile type and correlated with the thickness of the compacted layer in the LV posterior wall (LVPWC) and LV end-diastolic dimension (LVDD) Z-score, but not to the noncompacted to compacted layer (N/C) ratio. Survival analysis showed prognosis was similarly poor for both types after 2 decades. The significant risk factors for death, heart transplantation or implantable cardioverter-defibrillator insertion were congestive HF at diagnosis and lower LVPWC Z-score but not age of onset.

CONCLUSIONS

LVNC of both types showed poor long-term prognosis, therefore ongoing follow-up is recommended into adulthood. HF at diagnosis and LVPWC hypoplasia are major determinants of poor prognosis.

Non-compaction cardiomyopathy in an asymptomatic athlete

Prevention of sudden cardiac death in athletes requires the screening and recognition of pathologies that often remain clinically silent for years until provoked by a physiologic stressor. This can result in the manifestation of disease and even death. Left ventricular non-compaction cardiomyopathy (LVNC), newly classified as a distinct entity arising in the adult population, is a cardiomyopathy that at initial presentation can manifest as a wide spectrum of symptoms from asymptomatic to ventricular arrhythmias, systemic embolism and even sudden cardiac death. We present the case of an asymptomatic athlete found to have LVNC and discuss the implications this finding may have on sports participation.

Usefulness of Fragmented QRS Complex to Predict Arrhythmic Events and Cardiovascular Mortality in Patients With Noncompaction Cardiomyopathy

We aimed to evaluate the prevalence and prognostic role of fragmented QRS complex (fQRS) in predicting arrhythmic events and cardiovascular mortality in patients with noncompaction cardiomyopathy (NCC). A total of 88 patients (64.8% men, mean age 38.6 ± 17.7 years) with the diagnosis of NCC were enrolled. Median follow-up time was 42.4 months. The fQRS was defined as the presence of ≥1 additional R wave (R') or notch on the R/S waves in ≥2 contiguous leads representing anterior (V1 to V5), inferior (II, III, and aVF), or lateral (I, aVL, and V6) myocardial segments. Compared to patients without fQRS group, patients with fQRS (fQRS (+) group) showed higher rates for total arrhythmic events, ventricular tachycardia, bradyarrhythmia requiring pacemaker, sudden cardiac death, cardiovascular mortality, and all-cause mortality. The cut-off point of ≥3 leads for the fQRS was the optimal point discriminating an arrhythmic event and cardiovascular mortality. In Kaplan-Meier survival analysis, total arrhythmic events and cardiovascular mortality occurred more frequently in the fQRS (+) group. In multivariate Cox proportional hazard regression analysis, after adjusting for other confounding factors, the presence of fQRS were found to be as an independent predictor of arrhythmic events (hazard ratio 3.850, 95% CI 1.062 to 9.947, p = 0.002) and cardiovascular mortality (hazard ratio 2.719, 95% CI 1.494 to 9.262, p = 0.005). In conclusion, the presence of fQRS complex, as a simple and feasible electrocardiographic marker, seems to be a novel predictor of arrhythmic events and cardiovascular mortality in patients with NCC. This simple parameter may be used in identifying patients at high risk for arrhythmic events and so individualization of specific therapies can be applied.

A Unique Case of a 12-Year-Old Boy With Noonan Syndrome Combined With Noncompaction of the Ventricular Myocardium

A 12-year-old Chinese boy was admitted with dyspnea after exercise. Based on his clinical features, echocardiography tests, and family history, he was diagnosed with Noonan syndrome (NS) combined with noncompaction of the ventricular myocardium (NVM). Noonan syndrome (NS) is a common syndrome, but to the best of our knowledge, our case is the first reported case of NS combined with NVM. In our case, the detected mutated genes may be inherited and unreported genes caused NS or NVM. Our research may enrich our knowledge about NS and contribute to furthering our understanding of the pathogenesis and treatment. In summary, we present a unique case of NS combined with NVM.

A Rare Case of Renal Infarct due to Noncompaction Cardiomyopathy: A Case Report and Literature Review

Left ventricular noncompaction cardiomyopathy is a rare myocardial disorder which results from failure of left ventricle to compact in embryogenesis. We present a case of a 53-year-old female who came because of abdominal pain and was found to have renal infarct secondary to noncompaction cardiomyopathy.

Left Ventricular Non-compaction: Is It Genetic?

Left ventricular non-compaction (LVNC) is reported to affect 0.14 % of the pediatric population. The etiology is heterogeneous and includes a wide number of genetic causes. As an illustration, we report two patients with LVNC who were diagnosed with a genetic syndrome. We then review the literature and suggest a diagnostic algorithm to evaluate individuals with LVNC. Case 1 is a 15-month-old girl who presented with hypotonia, global developmental delay, congenital heart defect (including LVNC) and facial dysmorphism. Case 2 is a 7-month-old girl with hypotonia, seizures, laryngomalacia and LVNC. We performed chromosomal microarray for both our patients and detected chromosome 1p36 microdeletion. We reviewed the literature for other genetic causes of LVNC and formulated a diagnostic algorithm, which includes assessment for syndromic disorders, inborn error of metabolism, copy number variants and non-syndromic monogenic disorder associated with LVNC. LVNC is a relatively newly recognized entity, with heterogeneity in underlying etiology. For a systematic approach of evaluating the underlying cause to improve clinical care of these patients, a diagnostic algorithm for genetic evaluation of patients with LVNC is proposed.

Fetal Ventricular Hypertrabeculation/Noncompaction: Clinical Presentation, Genetics, Associated Cardiac and Extracardiac Abnormalities and Outcome

Left ventricular hypertrabeculation/noncompaction (LVHT) is a cardiac abnormality of unknown etiology. Aim of the review was to summarize the current knowledge about fetal LVHT, including clinical presentation, associated cardiac and extracardiac abnormalities and outcome. In 88 cases, LVHT was diagnosed by fetal echocardiography. In 36 %, no additional cardiac abnormalities were reported; in the remaining 64 %, one or more cardiac abnormalities were reported. Eight cases died prenatally, 17 were electively terminated, and 24 patients died after birth. Six patients were lost to follow-up, and 33 patients are alive at a mean age of 26 months. Surviving cases presented less frequently with fetal hydrops (13 vs. 62 %, p = 0.0004), complete heart block (27 vs. 78 %, p = 0.0076), more than three associated cardiac abnormalities (9 vs. 47 %, p = 0.0008) and more frequently with isolated LVHT (52 vs. 19 %, p = 0.009) than cases who died. Of the surviving patients, 16 received pharmacotherapy, three received pacemakers, eight underwent surgical procedures and four underwent heart transplantation. Postnatal regression of left ventricular hypertrophy and development of LVHT was found in four cases, improvement in cardiac function in two, and regression of right VHT in two. At autopsy, endocardial fibrosis was the most frequent abnormality in 92 %. Thirty-eight percentage of cases with fetal LVHT survived. Fetal and postnatal echocardiographic findings challenge the "embryonic pathogenetic" hypothesis of LVHT. Furthermore, fetal pathoanatomic findings like endocardial fibrosis might play a role in clarifying the still unsolved pathogenesis of LVHT.

Left Ventricular Noncompaction Diagnosis and Management Relevant to Pre-participation Screening of Athletes

Left ventricular noncompaction (LVNC) has been extensively studied over the last years, and an increasing number of cases have been reported worldwide, with a large proportion comprising young and asymptomatic subjects, including athletes. The current epidemic of LVNC is likely the consequence of several causes, that is, the increased awareness of the disease and the refined cardiovascular imaging techniques. The current diagnostic methods, based uniquely on definition of morphologic findings, do not always resolve the overlap of a physiological myocardial architecture comprising a prominent trabecular pattern from a mild phenotypic expression of the real disease. Appropriate criteria for identification and management of LVNC in athletes have, therefore, become a novel challenge for cardiologists and sport physicians, who are required to solve the question of diagnosis and appropriate management in the setting of pre-participation cardiovascular screening. Indeed, although it is important to timely identify a true myocardial disease, to reduce the burden of adverse cardiac event in a young athlete, in contrast, a misdiagnosis of LVNC may lead to unwarranted restriction of the athlete lifestyle, with detrimental psychological, social, and economic consequences. This review report has been planned, therefore, to help physicians in diagnosing and managing athletes presenting with a morphologic pattern suggestive of LVNC with specific focus on criteria for advising sport participation.