True diverticuli of the left ventricle refer to congenital anomalies affecting the left ventricle.
The condition typically occurs in children and is thought to occur in around 0.4% of cases based on autopsy studies.
In isolated cases, they are often asymptomatic and typically discovered incidentally.
A left ventricular diverticulum is a pouch or sac branching out from the ventricle. They have a variable size and can range from 5 mm to 80-90 mm. It is thought to arise as a developmental anomaly, from around the 4th embryonic week. Their connection to the ventricle may be narrow or wide.
They can be classified into two types 1:
- muscular type
- often originates at the apex and comprises mainly muscular fibres that contract synchronously with the ventricle
- often associated with other congenital defects
- fibrous diverticulum: composed of mostly fibrous tissue
They can be associated with other anatomic defects that involve the thoracoabdominal midline, and have syndromic associations such as pentalogy of Cantrell. Apical diverticula have a higher association with other anomalies. Diverticula occur in isolation in around 30% of cases.
They are commonly found in the apex and perivalvular area, although they have been reported in almost all locations of the ventricular wall with the exception of the interventricular septum 4.
Can have a variable appearance based on its size and position but in general, is seen as a tubular outpouching arising from the ventricle. Some authors suggest the diagnosis can be made after exclusion of coronary arterial disease, local or systemic inflammation or traumatic aetiologies as well as cardiomyopathies 7.
They often show synchronous contractility and small diverticula can close during systole.
Often show synchronous contractility 8.
Treatment and prognosis
Surgical resection is often the treatment of choice in symptomatic patients while management strategies in asymptomatic patients are often challenging. Other described treatment options include anticoagulation following after systemic embolisation, radiofrequency ablation or implantation of an implantable cardioverter defibrillator combined with class I or III antiarrhythmic drugs (e.g. in cases of associated symptomatic ventricular tachycardia) 7.
Recognised complications include:
- cardiac arrhythmias
- sudden death
- systemic emboli
- heart failure
- cardiac rupture
- intraventricular obstruction
Possible imaging differential considerations include:
- 1. Sherif HM, Maniar HS, Spadea N et-al. Left ventricular diverticulum mimicking ventricular pseudoaneurysm in an adult. Tex Heart Inst J. 2011;37 (5): 584-6. Free text at pubmed - Pubmed citation
- 2. Shah D, Kumar CP, Shah MS et-al. Case series: Congenital left ventricular diverticulum. Indian J Radiol Imaging. 2010;20 (3): 211-4. doi:10.4103/0971-3026.69356 - Free text at pubmed - Pubmed citation
- 3. Bayrak F, Fatih B, Guneysu T et-al. Isolated left ventricular diverticulum in an asymptomatic patient. Eur. Heart J. 2007;28 (13): 1591. doi:10.1093/eurheartj/ehl513 - Pubmed citation
- 4. Srichai MB, Hecht EM, Kim DC et-al. Ventricular diverticula on cardiac CT: more common than previously thought. AJR Am J Roentgenol. 2007;189 (1): 204-8. doi:10.2214/AJR.06.1223 - Pubmed citation
- 6. Dwivedi AN, Thangiah AG, Rai M et-al. Computed tomographic features of congenital left ventricular diverticulum. J Clin Imaging Sci. 2012;2 (1): 48. doi:10.4103/2156-7514.99182 - Free text at pubmed - Pubmed citation
- 7. Ohlow MA. Congenital left ventricular aneurysms and diverticula: definition, pathophysiology, clinical relevance and treatment. Cardiology. 2006;106 (2): 63-72. doi:10.1159/000092634 - Pubmed citation
- 8. Sharma A, Kumar S. Overview of left ventricular outpouchings on cardiac magnetic resonance imaging. Cardiovasc Diagn Ther. 2015;5 (6): 464-70. doi:10.3978/j.issn.2223-3652.2015.11.02 - Free text at pubmed - Pubmed citation