Congenital left ventricular wall abnormalities in adults detected by gated cardiac multidetector computed tomography: clefts, aneurysms, diverticula and terminology problems

Prevalence of Left Ventricular Myocardial Crypts in Japanese Patients

Objective Myocardial crypts are congenital abnormalities associated with hypertrophic cardiomyopathy (HCM) and other conditions. This study assessed the prevalence of myocardial crypts in Japanese patients. Methods Myocardial crypts were evaluated in a consecutive series of 300 patients (13-92 years old) who underwent computed tomography angiography (CTA) because of clinical suspicion of ischemic heart disease. Results We found a myocardial crypt incidence of 9.7% (29 patients) in our study population, with multiple crypts observed in 2.3% (7 patients). Among these, myocardial crypts were found in 2 out of 8 (25%) patients with hypertrophic cardiomyopathy (HCM), 1 of which was apical-type HCM. In patients with a single crypt (22 patients), the most common location of the crypt was at the left ventricular apex (16/22 patients, 72.7%), followed by the inferior wall (5/22 patients, 22.7%) and the interventricular septum (1/22 patients, 4.6%). Conclusion The incidence of myocardial crypts observed in our study aligns with that reported in previous studies, although the most common location among the Japanese population was the left ventricular apex.

Isolated muscular ventricular diverticulum assessment using multi-parameter echocardiographic imaging: Case reports

Ventricular diverticulum (VDi) is a rare and often asymptomatic congenital cardiac malformation detected incidentally as an outpouching on routine imaging examination, of which the muscular type has been less reported. Here, two patients were incidentally found to have outpouchings of the ventricle during routine transthoracic echocardiography. After a series of multi-parameter echocardiography examination, including two-dimensional (2D), three-dimensional (3D) photo-realistic rendering, blood speckle tracking (BST), and contrast enhancement, to provide morphological structure, spatial relationship, and blood flow information, both cases were finally diagnosed with muscular VDi. These cases highlight the advantages of using multi-parameter echocardiography for the comprehensive assessment of muscular VDi.

The Use of Multimodality Imaging for the Diagnosis of Myocardial Outpouchings and Invaginations: A Systematic Review

Cardiac ventricular outpouchings and invaginations are rare structural abnormalities and usually incidental findings during cardiac imaging. A definitive diagnosis is possible through the use of multimodality imaging. A systematic review of the literature was carried out in November 2022 to identify studies regarding ventricular outpouchings and invaginations. The main aim of the review is to summarize knowledge regarding epidemiology, etiology, diagnosis and prognosis of patients with ventricular outpouchings (aneurisms or diverticula) and invaginations (crypts and recesses). Overall, 26 studies published between 2000 and 2020 were included in the review. Diverticula and congenital aneurysms incidence ranges between 0.6 and 4.1%. Myocardial recesses and crypts range between 9% in the general population and up to 25% in patients with hypertrophic cardiomyopathy. The combined use of echocardiography, cardiac computed tomography (CCT) and cardiac magnetic resonance (CMR) is useful to establish tissue contractility, fibrosis, extension and relationship with adjacent structures for differential diagnosis of both invaginations and outpouchings. In conclusion, both outpouchings and invaginations are rare entities: a definitive diagnosis may be aided by the use of combining multiple imaging techniques, and the treatment depends both on the lesion-specific risk of complications and on the potential association of some lesions with cardiomyopathy.

[Ventricular diverticulum in Cantrell´s pentalogy: rare but not isolated entities]

Pentalogy of Cantrell is a rare entity characterized by a combination of alterations, among which the following stand out: defects of the pericardium, heart, diaphragm, lower third of sternum and abdominal wall. On the other hand, congenital cardiac diverticulum is a rare malformation whose presentation is associated with Cantrell's pentalogy in some cases. We present the case of a child with Cantrell's pentalogy who, during follow-up, was diagnosed with left ventricular diverticulum, which required surgical management with a favorable outcome. Addressing these conditions requires the use of cardiovascular images that allow timely decision-making by the treating team.

Incidental detection of myocardial clefts in a patient with acute inferior ST-segment elevation myocardial infarction: a very unusual and potentially ominous association—a case-report

Background

The crescent availability of high-resolution cardiac imaging allows detection of myocardial structural variations. Differentiate these entities from others with different clinical significance can be challenging. Clinicians should be familiar with myocardial clefts to avoid erroneous diagnosis.

Case summary

A 63-year-old smoker man alerted the emergency medical system for sudden chest pain. The electrocardiogram showed Pardee wave in inferior leads. Coronary angiography evidenced a 100% occlusion of right coronary artery that was treated by angioplasty and drug-eluting stent implantation with optimal angiographic result. At ventriculography, two fissure-like protrusion were observed in the inferior wall. Urgent transthoracic echocardiogram (TTE) demonstrated two deep fissures on the mid-inferior wall, contained by a thin sub-epicardial layer, with sub-total obliteration during systole. A diagnosis of myocardial clefts was suspected and after Heart Team discussion, a conservative strategy was proposed. Early cardiac magnetic resonance (CMR) confirmed two myocardial crypts on the mid-inferior wall. Stability of myocardial fissures and absence of left ventricular remodelling was confirmed by TTE, in a 2 years of follow-up period.

Discussion

Myocardial cleft should always be considered in the differential diagnosis of myocardial wall defects. In a patient presenting with an acute myocardial infarction, the main differential diagnosis is pseudoaneurysm. In this setting modified TTE views and meticulous analysis of CMR sequences are recommended to confirm the diagnosis and estimate the risk of myocardial rupture.

A Sensible Approach to Diagnosing Cardiac Aneurysms, Pseudoaneurysms and Common Mimickers

The heart can manifest a spectrum of focal convexities that range from insignificant crypts and diverticula to clinically relevant aneurysms and pseudoaneurysms. The distinction of a clinically significant lesion from a minor focal convexity can be challenging. This article outlines the various types of focal convexities on the basis of location within the heart and discusses unique morphologic and functional features to further characterize these entities. We also highlight the most critical clinical consequences of cardiac aneurysms and pseudoaneurysms such as thromboembolic events, aneurysm ruptures, intracardiac shunting, hemopericardium, and arrhythmias.

Multimodality Imaging and Clinical Significance of Congenital Ventricular Outpouchings: Recesses, Diverticula, Aneurysms, Clefts, and Crypts

The high spatial resolution of cardiac computed tomography (CT) and cardiac magnetic resonance (CMR) permit the diagnosis of congenital ventricular outpouchings (CVOs), including congenital ventricular diverticula (CVD), congenital ventricular aneurysms (CVA), clefts, and crypts. A unique classification has not been established, and these terms are used interchangeably with confounding terminology. Moreover, their significance is not univocal. A research was performed using PubMed on six subjects: (1) congenital left ventricular outpouchings; (2) congenital ventricular diverticulum; (3) congenital ventricular aneurysm; (4) ventricular clefts; (5) ventricular crypts; and (6) ventricular crevices. Usually, CVOs are small with a preserved contraction and in asymptomatic patients, the clinical relevance may be minimal, although electrocardiographic anomalies are often present. CVA and diverticula may carry an embolic risk and cases of arrhythmia and rupture are described. In the presence of clefts, or crypts a cardiomyopathy should be excluded. A simple classification can be proposed: CVD extend beyond the myocardial wall and fibrous type may be termed CVA, acquired forms should be kept distinct. Clefts, or crypts, are small recesses extending for more than 50% of the ventricular wall but not beyond its margin. The presence of fibrosis may be evaluated by CMR. A multicenter prospective registry would be helpful to investigate potential clinical implications and to exclude dubious forms of hypertrophic cardiomyopathy or ventricular noncompaction. In conclusion, CVOs have been described with different terminologies and classifications. Their significance needs to be interpreted in the clinical setting and with the help of a multimodality imaging, particularly of CMR.

Geriatric Presentation of Idiopathic Left Ventricular Aneurysm

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Idiopathic left ventricular aneurysm is a rare diagnosis.

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Management and prognosis of idiopathic left ventricular aneurysms remain unknown.

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We describe a conservative management of an idiopathic left ventricular aneurysm in a geriatric patient.

The embryological basis of subclinical hypertrophic cardiomyopathy

Hypertrophic cardiomyopathy (HCM) is caused by mutations in sarcomeric proteins, the commonest being MYBPC3 encoding myosin-binding protein C. It is characterised by left ventricular hypertrophy but there is an important pre-hypertrophic phenotype with features including crypts, abnormal mitral leaflets and trabeculae. We investigated these during mouse cardiac development using high-resolution episcopic microscopy. In embryonic hearts from wildtype, homozygous (HO) and heterozygous (HET) Mybpc3-targeted knock-out (KO) mice we show that crypts (one or two) are a normal part of wildtype development but they almost all resolve by birth. By contrast, HO and HET embryos had increased crypt presence, abnormal mitral valve formation and alterations in the compaction process. In scarce normal human embryos, crypts were sometimes present. This study shows that features of the human pre-hypertrophic HCM phenotype occur in the mouse. In an animal model we demonstrate that there is an embryological HCM phenotype. Crypts are a normal part of cardiac development but, along with the mitral valve and trabeculae, their developmental trajectory is altered by the presence of HCM truncating Mybpc3 gene mutation.

Use of Unique Doppler Flow‐Pattern for the Diagnosis of Left Ventricular Diverticulum

Isolated congenital left ventricular diverticulum (LV) is reportedly a rare finding. It is frequently associated with other congenital defects involving heart, pericardium, sternum, diaphragm, and abdominal wall. It is an outpouching from the ventricle and has all three layers of left ventricular free walls. We present the case of a 53‐year‐old woman who was discovered to have an outpouching of the LV apex on a nongated chest CT scan raising possibility of a pseudoaneurysm. A transesophageal echocardiogram (TEE) showed systolic diminution of this outpouching with unique Doppler flow‐patterns suggesting a diagnosis of a muscular type of LV diverticulum instead of a postinfarct LV pseudoaneurysm. The patient was reassured and treated conservatively.

Prognostic role of isolated left ventricular diverticuli detected by cardiovascular magnetic resonance

BACKGROUND

Isolated left ventricular diverticulum, a rare cardiac malformation, can be asymptomatic or associated with systemic embolization, ventricular arrhythmias, or sudden death. MRI allows for the detection of diverticuli and the distinction between fibrous and muscular types using the delayed enhancement technique.

AIM

To evaluate the prevalence of left ventricular diverticuli in nonselected consecutive patients who had undergone MRI.

METHODS

In a total of 3273 consecutive patients who had undergone cardiac magnetic resonance from January 2001 to December 2005, isolated ventricular diverticuli were found in 25 patients (0.76%), with no apparent cardiac disease. A delayed enhancement technique was used to distinguish fibrous and muscular types. The prevalence of complications was evaluated with a follow-up of 52 ± 8 months.

RESULTS

The site of the left ventricular diverticuli was the septum in 10 (37%) cases, inferior wall in 6 (22%) cases, lateral wall in 4 (15%) cases, and apical in 7 (26%) cases. In two cases, multiple diverticuli were found. In delayed enhancement images, a partial or total fibrous diverticulum was found in 6 (24%) patients. At follow-up, clinical complications were recorded in 6 (24%) patients; 2 (8%) patients had arrhythmic complications and 4 (12%) patients had embolic complications of presumed cardiac origin. In addition, two patients (8%) had nonsustained ventricular tachycardia diagnosed using 24-h ECG Holter monitoring. Fibrous type diverticuli were associated with a higher incidence of arrhythmic complications than the muscular type.

CONCLUSION

The prevalence of isolated ventricular diverticuli detected by MRI is higher than that previously reported with other imaging techniques. Fibrous diverticuli are associated with a higher incidence of arrhythmic complications.

Prediction of sarcomere mutations in subclinical hypertrophic cardiomyopathy

BACKGROUND

Sarcomere protein mutations in hypertrophic cardiomyopathy induce subtle cardiac structural changes before the development of left ventricular hypertrophy (LVH). We have proposed that myocardial crypts are part of this phenotype and independently associated with the presence of sarcomere gene mutations. We tested this hypothesis in genetic hypertrophic cardiomyopathy pre-LVH (genotype positive, LVH negative [G+LVH-]).

METHODS AND RESULTS

A multicenter case-control study investigated crypts and 22 other cardiovascular magnetic resonance parameters in subclinical hypertrophic cardiomyopathy to determine their strength of association with sarcomere gene mutation carriage. The G+LVH- sample (n=73) was 29 ± 13 years old and 51% were men. Crypts were related to the presence of sarcomere mutations (for ≥1 crypt, β=2.5; 95% confidence interval [CI], 0.5-4.4; P=0.014 and for ≥2 crypts, β=3.0; 95% CI, 0.8-7.9; P=0.004). In combination with 3 other parameters: anterior mitral valve leaflet elongation (β=2.1; 95% CI, 1.7-3.1; P<0.001), abnormal LV apical trabeculae (β=1.6; 95% CI, 0.8-2.5; P<0.001), and smaller LV end-systolic volumes (β=1.4; 95% CI, 0.5-2.3; P=0.001), multiple crypts indicated the presence of sarcomere gene mutations with 80% accuracy and an area under the curve of 0.85 (95% CI, 0.8-0.9). In this G+LVH- population, cardiac myosin-binding protein C mutation carriers had twice the prevalence of crypts when compared with the other combined mutations (47 versus 23%; odds ratio, 2.9; 95% CI, 1.1-7.9; P=0.045).

CONCLUSIONS

The subclinical hypertrophic cardiomyopathy phenotype measured by cardiovascular magnetic resonance in a multicenter environment and consisting of crypts (particularly multiple), anterior mitral valve leaflet elongation, abnormal trabeculae, and smaller LV systolic cavity is indicative of the presence of sarcomere gene mutations and highlights the need for further study.

Prevalence of myocardial crypts in a large retrospective cohort study by cardiovascular magnetic resonance

BACKGROUND

Myocardial crypts are discrete clefts or fissures in otherwise compacted myocardium of the left ventricle (LV). Recent reports suggest a higher prevalence of crypts in patients with hypertrophic cardiomyopathy (HCM) and also within small samples of genotype positive but phenotype negative relatives. The presence of a crypt has been suggested to be a predictor of gene carrier status. However, the prevalence and clinical significance of crypts in the general population is unclear. We aimed to determine the prevalence of myocardial crypts in a large cohort of subjects using clinical cardiovascular magnetic resonance (CMR).

METHODS

Consecutive subjects referred for clinical CMR during a 12-month period (n = 1020, age 52.6 ± 17, males: 61%) were included. Crypts were defined as >50% invagination into normal myocardium and their overall prevalence, location and shape was investigated and compared between different patient groups.

RESULTS

The overall prevalence of crypts was 64/1020 (6.3%). In a predefined 'normal' control group the prevalence was lower (11/306, 3.6%, p = 0.031), but were equally prevalent in ischemic heart disease (12/236, 5.1%, p = n/s) and the combined non-ischemic cardiomyopathy (NICM) groups (24/373; 6.4%, p = n/s). Within the NICM group, crypts were significantly more common in HCM (9/76, 11.7%, p = 0.04) and hypertensive CM subjects (3/11, 27%, p = 0.03). In patients referred for CMR for family screening of inherited forms of CM, crypts were significantly more prevalent (10/41, 23%, p < 0.001), including a smaller group with a first degree relative with HCM (3/9, 33%, p = 0.01).

CONCLUSION

Myocardial crypts are relatively common in the normal population, and increasingly common in HCM and hypertensive cardiomyopathy. Crypts are also more frequently seen in normal phenotype subjects referred because of a family history of an inherited cardiomyopathy and HCM specifically. It is uncertain what the significance of crypts are in this group, and because of variability in the imaging protocols used and their relative frequency within the normal population, should not be used to clinically stratify these patients. Prospective studies are required to confirm the clinical significance of myocardial crypts, as their significance remains unclear.

Congenital left ventricular outpouchings: a systematic review of 839 cases and introduction of a novel classification after two centuries

BACKGROUND

Congenital left ventricular outpouchings (LVOs) are reported under five overlapping and poorly defined terms including left ventricular accessory chamber, left ventricular aneurysm (LVA), left ventricular diverticulum (LVD), double-chambered LV, and accessory left ventricle. Diagnostic criteria are frequently mixed and not mutually exclusive. They convey no information regarding treatment strategy and prognosis.

OBJECTIVES

The aim of this systematic review is to provide a clear and inclusive classification, with therapeutic and prognostic implications, for congenital LVOs.

DATA SOURCES

We performed three separate sets of search on three subjects including "congenital left ventricular outpouchings," "important and simply measurable markers of left ventricular function," and "relationship of mechanics of intraventricular blood flow and optimal vortex formation in left ventricle and elliptical geometry of LV."

STUDY ELIGIBILITY CRITERIA

We enrolled case series, review articles, and case reports with literature review. All types of acquired LVO's were excluded.

STUDY APPRAISAL AND SYNTHESIS METHODS

We studied the abstracts of all searched articles. We focused on diagnostic criteria and patients' outcome. To examine the validity and reliability of the novel classification, fifteen previous studies were revisited using the novel classification.

RESULTS

A total of 20 papers from 11 countries fulfilled our inclusion criteria. The age of patients ranged from prenatal age to geriatric age range. Diagnostic criteria were clearly stated only for two of the above five terms (i.e., congenital LVA and congenital LVD). Cases with mixed diagnostic criteria were frequent.Elliptical geometry of left ventricle was found to have significant impact on effective blood flow mechanics in LV. A simple inclusive classification for congenital LVOs, with therapeutic and prognostic implications, was introduced.

CONCLUSION

The cornerstone of this classification is elliptical LV geometry. Large-type IIc LVO have dismal prognosis, if left untreated. LVO type I and small LVO type IIa have the best prognosis.

Congenital left ventricular diverticulum: Multimodality imaging evaluation and literature review

Congenital ventricular diverticulum is a rare cardiac malformation. We present the case of a 57-year-old man who underwent cardiac catheterization for suspected unstable angina. No coronary artery disease was diagnosed and a left ventricular diverticulum was incidentally found. Coronary CT and cardiac MRI were performed in order to confirm the diagnosis of a muscular type diverticulum and to exclude a post-ischemic aneurysm.

Significance of left ventricular clefts-A case report

We describe the case of a 48-year-old patient who presented with an out-of-hospital cardiac arrest due to an acute ST-elevation myocardial infarction. Left ventriculography performed during the initial coronary angiography revealed the presence of structural abnormalities in the myocardial wall which subsequently, with the use of contrast echocardiography and cardiac magnetic resonance imaging, were confirmed to represent ventricular clefts. We reviewed the pathophysiological significance of these defects and compared them with similarly looking abnormalities such as aneurysms, pseudoaneurysms, and diverticula. In conclusion, recognition of ventricular clefts is needed to allow clinicians to differentiate them from other myocardial wall defects with different pathological profile and clinical significance. <Learning objective: With emerging techniques in cardiac imaging some cardiac abnormalities such as left ventricular (LV) clefts are recognized more frequently. This case report describes an incidental finding of LV cleft and provides an extensive review of the literature regarding the clinical significance and differential from other similar findings of different pathology. That will help physicians to distinguish these overlapping findings and tailor patients' management accordingly.>.

Anatomical features and clinical importance of left atrial diverticula: MDCT findings

To assess the anatomical features and clinical importance of left atrial diverticula and atrial accessory appendages in patients undergoing cardiac computed tomography with multidetector computed tomography. A total of 1305 consecutive patients (385 female, 29.5%; 920 male, 70.5%) were assessed using electrocardiogram-gated computed tomography between May 2010 and June 2013. The anatomical features and the prevalences of left atrial diverticula and left atrial accessory appendages were retrospectively assessed by four radiologists. The relationships between the prevalence and size of the diverticula and the age and gender of the patients were assessed. Among the 1305 patients, 610 (46.7%) exhibited 708 left atrial diverticula, and 62 (4.8%) exhibited left atrial accessory appendages. The most common locations of the left atrial diverticula were the right anterior superior wall (n = 328, 46.3%) and the lateral superior wall (n = 96, 13.5%). In addition to classical cystic and tubular diverticula, 49 (3.7%) of the patients exhibited mixed (cystic-tubular), conical, or hook-shaped diverticula and diverticular forms containing mural calcifications. There was no significant relationship between the prevalence of diverticula and the age and gender of the patients (P > 0.05). In addition to tubular and cystic diverticula, the left atrial wall can host different diverticular forms (such as mixed, conical, calcific, and hook shaped). It could be beneficial to assess the left atrium using MDCT to determine the source of emboli in cryptogenic embolism and to reduce complications associated with interventional procedures performed for left atrial arrhythmias.