> Table of Contents > Ventricular Septal Defect
Ventricular Septal Defect
Ian D. Thomas, MD
Brent J. Barber, MD
image BASICS
DESCRIPTION
  • Congenital or acquired defect of the interventricular septum that allows communication of blood between the left and the right ventricles
  • Other than bicuspid aortic valve, it is the most common congenital heart malformation reported in infants and children. It also occurs as a complication of acute myocardial infarction (MI).
  • Severity of the defect is correlated with its size, with large defects being the most severe.
  • Blood flow across the defect typically is left to right, depending on defect size and pulmonary vascular resistance (PVR).
  • Prolonged left to right shunting of blood can lead to pulmonary hypertension (HTN). This may eventually lead to a reversal of flow across the defect and cyanosis (Eisenmenger complex).
Geriatric Considerations
Almost entirely associated with MI
Pediatric Considerations
Congenital defect
EPIDEMIOLOGY
Incidence
  • Congenital defect: no gender predilection, occurs in ˜2/1,000 live births and accounts for 30% of all congenital cardiac malformations
  • Post-MI: Males are affected more than females.
Prevalence
In the United States:
  • Congenital defect: lowered prevalence in adults due to spontaneous closure
  • Post-MI: estimated to complicate 1-3%
ETIOLOGY AND PATHOPHYSIOLOGY
  • Congenital
  • In adults, complication of MI
Genetics
Multifactorial etiology; autosomal dominant and recessive transmissions have been reported.
RISK FACTORS
  • Congenital:
    • Risk of sibling being affected: 4.2%
    • Risk of offspring being affected: 4%
    • Prematurity
  • Complication of MI:
    • First MI
    • HTN
    • Most frequently within first week after MI
    • Occurs in 1-3% of MIs, most commonly after anterior MI
GENERAL PREVENTION
Avoid prenatal exposure to known risk factors (ibuprofen, marijuana, organic solvents, febrile illness). For adults, avoid risk factors for MI and obtain evaluation before pregnancy.
COMMONLY ASSOCIATED CONDITIONS
  • Congenital:
    • Tetralogy of Fallot
    • Aortic valvular deformities, especially aortic insufficiency and bicuspid aortic valve
    • Down syndrome (trisomy 21), endocardial cushion defect
    • Transposition of great arteries
    • Coarctation of aorta
    • Tricuspid atresia
    • Truncus arteriosus
    • Patent ductus arteriosus
    • Atrial septal defect
    • Pulmonic stenosis
    • Subaortic stenosis
  • Adult: coronary artery disease
image DIAGNOSIS
PHYSICAL EXAM
  • Small defect:
    • Harsh holosystolic murmur loudest at left lower sternal border
    • Detected after PVR drops at 4 to 8 weeks of life
  • Moderate defect:
    • Harsh holosystolic murmur at left lower sternal border associated with a thrill
    • Forceful apical impulse with lateral displacement
    • Increased intensity of P2
    • Diastolic rumble at apex due to increased flow across the mitral valve
  • Large defect:
    • Holosystolic murmur heard throughout the precordium with diastolic rumble at apex with precordial bulge and hyperactivity, although large defects may have little or no murmur initially
    • If congestive heart failure (CHF) exists: tachycardia, tachypnea, and hepatomegaly
    • If pulmonary HTN exists: cyanosis with exertion
    • If Eisenmenger complex is present: cyanosis and clubbing
DIFFERENTIAL DIAGNOSIS
  • Any defect with left-to-right shunt, such as patent ductus arteriosus, atrial septal defect
  • Children: tetralogy of Fallot
  • Adults: mitral regurgitation
DIAGNOSTIC TESTS & INTERPRETATION
Initial Tests (lab, imaging)
  • A 12-lead ECG may suggest severity of VSD. Initially, left ventricular hypertrophy and left atrial enlargement may be evident. As pulmonary HTN develops, right ventricular hypertrophy and right atrial enlargement may be seen.
  • A chest x-ray (CXR) may demonstrate increased pulmonary vascularity and/or cardiomegaly.
  • A 2D echocardiogram for visualization of location and size of defect
  • Color flow Doppler for direction and velocity of VSD jet; may be used to estimate right ventricular pressure
Follow-Up Tests & Special Considerations
  • Weight and hematocrit check
  • Cardiac catheterization performed occasionally for perioperative planning or to assess need for closure of defect
Diagnostic Procedures/Other
  • Cardiac catheterization (left and right sides of heart) can confirm the diagnosis, document number of defects, quantify ratio of pulmonary blood flow to systemic blood flow (Qp/Qs), and determine PVR.
  • Demonstration of an oxygen saturation step up from the right atrium to the distal pulmonary artery
Test Interpretation
  • Congenital VSD (four major anatomic types)
    • Membranous (70%)
    • Muscular (20%)
    • Atrioventricular canal type (5%)
    • Supracristal (5%; higher in Asians)
  • Post-MI VSD predominantly involves muscular septum.
  • After surgical repair, right bundle branch block is common.
image TREATMENT
  • Start diuretic therapy if overload signs are present (1)[A].
  • Minimize IV fluids.
  • Consider ACE inhibitor and/or digoxin.
  • Nasogastric feeds for neonates
  • Correct anemia via iron supplementation or a possible RBC transfusion.
GENERAL MEASURES
  • Appropriate health care maintenance
  • Outpatient, until surgical repair is indicated
  • Inpatient in setting of acute MI
  • Inpatient for treatment of severe CHF
MEDICATION
First Line
  • Per the 2007 American Heart Association guidelines, endocarditis antibiotic prophylaxis is not recommended for most VSDs. It is recommended for VSDs associated with complex cyanotic heart disease, during the first 6 months after surgical repair, or for residual VSDs located near the patch following surgery (2)[A]. However, recent reports suggest that patients with a left ventricle to right atrium VSD (Gerbode defect) may be at higher risk for endocarditis and thus may also need antibiotic prophylaxis (3)[C].
  • Pediatric: Medications aim to control pulmonary edema, decrease work of breathing, and allow for growth:
    • Furosemide 1 to 2 mg/kg PO/IV once to twice a day
    • Spironolactone 1 to 2 mg/kg/day divided BID
    • Captopril
      • Infants: Oral: 0.3-2.5 mg/kg/day divided every 8-12 hours; max 2 mg/kg/day
      • Children and adolescents: Oral: 0.3-6 mg/kg/day divided every 8-12 hours; maximum daily dose: 150 mg/day
    • P.1113

    • Digoxin: infants <2 years of age, 10 &mgr;g/kg/day PO divided BID; children, 2 to 10 years of age, 5 to 10 &mgr;g/kg/day PO divided BID; children >10 years of age, 2 to 5 &mgr;g/kg/day PO divided BID
  • Adults: Digoxin and diuretics may be beneficial in some circumstances (1)[A].
  • Side effects:
    • Drugs that increase systemic vascular resistance may increase left-to-right shunting and cause signs and symptoms of pulmonary overcirculation.
    • HTN
Second Line
  • Surgical closure is generally indicated if the pulmonic-to-systemic flow is >2:1 or with poorly controlled pulmonary overcirculation despite maximal medical and dietary interventions.
  • If an infant with a VSD has persistent pulmonary HTN or failure to grow, surgical repair generally is recommended prior to 6 months of age even if patient is otherwise asymptomatic.
  • For post-MI VSDs, afterload reduction, inotropic support, intra-aortic balloon pump, and left ventricular assist device may be used to stabilize the patient prior to surgery. Surgical repair includes septal debridement and patch placement.
ISSUES FOR REFERRAL
Close follow-up of a congenital VSD is necessary until primary intracardiac repair is performed to ensure that significant pulmonary HTN does not develop.
ADDITIONAL THERAPIES
  • Infant caloric requirements up to 150 kcal/kg/day or more for adequate weight gain
  • Treatment of iron deficiency anemia to increase oxygen-carrying capacity
SURGERY/OTHER PROCEDURES
  • Surgical correction with either a VSD patch or repair is commonly used. Postsurgical outcomes for isolated VSD are excellent. Complications are rare and include reoperation for residual VSD, extended hospital stay, arrhythmias, valve injury, depressed ventricular function, and heart block (4)[B].
  • Percutaneous transcatheter device closure has become a safe and effective option for some children with small to moderate VSDs. Complications include valvular regurgitation, residual defects, and heart block. There is a greater risk of conduction abnormality with this technique compared to surgical closure. Recent studies have shown steroids may decrease this risk (5)[A].
  • Perventricular device closure (hybrid technique) of some subtypes of isolated VSDs without cardiopulmonary bypass is feasible under transesophageal echocardiographic (TEE) guidance. Complications are similar to percutaneous closure (6)[A].
INPATIENT CONSIDERATIONS
Admission Criteria/Initial Stabilization
  • Failure to thrive
  • Pulmonary overcirculation/CHF
  • Stabilize airway
  • Reduce temperature stress
Nursing
Frequent vital sign monitoring; daily weight and calorie counts
Discharge Criteria
CHF stabilization, weight gain, or successful repair
image ONGOING CARE
FOLLOW-UP RECOMMENDATIONS
  • Small VSDs without evidence of CHF or pulmonary HTN generally can be followed every 1 to 5 years after the neonatal period.
  • Moderate to large VSDs require more frequent follow-up.
  • Potential complications of VSDs include right ventricular outflow obstruction and aortic valve prolapse.
Patient Monitoring
  • Physical growth and development monitoring
  • Influenza vaccine for children >6 months of age
  • Palivizumab to children <12 months of age with hemodynamically significant lesions. Children with small VSDs do not need RSV prophylaxis (7)[A].
DIET
  • Low sodium in heart failure
  • High calorie in failure to thrive
PATIENT EDUCATION
  • No activity restriction in absence of pulmonary HTN
  • Parents need support and instructions for prevention of complications until the child is ready for surgery.
PROGNOSIS
  • Congenital:
    • Course is variable depending on the size of the VSD.
    • Small VSD: many will close spontaneously by age 3 years. Muscular defects are more likely to close spontaneously.
    • Large VSD: CHF or failure to thrive in infancy necessitating surgical repair.
    • 20-year cumulative survival rate after surgery for isolated VSD is 87%; 40 years is 78% (8).
    • Progressive pulmonary vascular disease and pulmonary HTN are the most feared complications of VSD caused by left-to-right shunting and may eventually lead to reversal of the shunt (Eisenmenger complex). Death usually occurs in the 4th decade of life if untreated.
  • Post-MI:
    • With medical management alone, 80-90% mortality in the first 2 weeks
    • Prognosis worse with inferior MI compared with anterior MI
REFERENCES
1. Faris RF, Flather M, Purcell H, et al. Diuretics for heart failure. Cochrane Database Syst Rev. 2012;(2):CD003838.
2. Wilson W, Taubert KA, Gewitz M, et al. Prevention of infective endocarditis: guidelines from the American Heart Association: a guideline from the American Heart Association Rheumatic Fever, Endocarditis, and Kawasaki Disease Committee, Council on Cardiovascular Disease in the Young, and the Council on Clinical Cardiology, Council on Cardiovascular Surgery and Anesthesia, and the Quality of Care and Outcomes Research Interdisciplinary Working Group. Circulation. 2007;116(15):1736-1754.
3. Lax D, Bhatt RD, Klewer SE, et al. Are all ventricular septal defects created equal? J Am Soc Echocardiogr. 2010;23(7):791.e5-791.e7.
4. Scully BB, Morales DL, Zafar F, et al. Current expectations for surgical repair of isolated ventricular septal defects. Ann Thorac Surg. 2010;89(2): 544-549.
5. Yang L, Tai BC, Khin LW, et al. A systematic review on the efficacy and safety of transcatheter device closure of ventricular septal defects (VSD). J Interv Cardiol. 2014;27(3):260-272.
6. Yin S, Zhu D, Lin K, et al. Perventricular device closure of congenital ventricular septal defects. J Card Surg. 2014;29(3):390-400.
7. American Academy of Pediatrics Committee on Infectious Diseases; American Academy of Pediatrics Bronchiolitis Guidelines Committee. Updated guidance for palivizumab prophylaxis among infants and young children at increased risk of hospitalization for respiratory syncytial virus infection. Pediatrics. 2014;134(2):415-420.
8. Menting ME, Cuypers JA, Opić P, et al. The unnatural history of the ventricular septal defect: outcome up to 40 years after surgical closure. J Am Coll Cardiol. 2015;65(18):1941-1951.
Additional Reading
&NA;
Penny DJ, Vick GW III. Ventricular septal defect. Lancet. 2011;377(9771):1103-1112.
See Also
&NA;
Down Syndrome; Acute Coronary Syndromes: NSTE-ACS (Unstable Angina and NSTEMI); Tetralogy of Fallot
Codes
&NA;
ICD10
  • Q21.0 Ventricular septal defect
  • I23.2 Ventricular septal defect as current comp following AMI
  • Q21.3 Tetralogy of Fallot
Clinical Pearls
&NA;
  • A loud 2/6 to 3/6 low-pitched harsh holosystolic murmur at the left lower sternal border is typical.
  • A diastolic rumble at the apex indicates moderate to large VSD or Qp:Qs >2:1, which likely will require surgical or percutaneous closure.
  • Disappearance of the murmur could be secondary to spontaneous closure of the defect or the development of pulmonary HTN.
  • Development of a new murmur of semilunar valve insufficiency should be further evaluated. Pulmonary regurgitation may occur as PVR increases, and the development of aortic regurgitation usually will require early surgery.