The peak age range for surgical intervention for patients with a bicuspid aortic valve is
60 to 80 years. Bicuspid aortic valve is the most common congenital cardiac anomaly with an incidence of 1% to 2% and a male predominance (4:1 sex ratio). Bicuspid aortic valve is sometimes inherited as an autosomal dominant trait with variable penetrance. Three morphologic types are recognized on the basis of commissural fusion: fusion of the left and right coronary cusps (most common), fusion of the right and non-coronary cusps, and fusion of the left and non- coronary cusps (least common). Sclerosis of the bicuspid aortic valve begins in the second decade and calcification may appear as early as the fourth decade. The peak age range for surgical intervention is between 60 and 80 years. Bicuspid aortic valve disease is associated with intrinsic abnormalities of the aortic media that predisposes to aortic root dilatation/aneurysm/rupture, and/or dissection. Other left-sided lesions associated with bicuspid aortic valve include coarctation of the aorta, subaortic stenosis, parachute mitral valve, VSD, and PDA.
References:
A 45-year-old man with known Ebstein anomaly seeks your advice with regard to optimal management. He is asymptomatic and has an active lifestyle without any limitations. His physical examination is remarkable for the absence of cyanosis. He has a loud holosystolic murmur at the left lower sternal border that is accentuated with respiration. He has no organomegaly or peripheral edema. His TTE reveals moderately severe 3+ TR with an RV systolic pressure of 35 mmHg and normal LV and RV systolic function. There is no evidence of interatrial communication.
Which of the following should you recommend?
Regular follow-up with repeat TTE in 6 months. Ebstein anomaly is characterized by apical displacement of the septal tricuspid leaflet of >8 mm/m2 and the presence of an elongated anterior tricuspid leaflet. The clinical presentation of Ebstein anomaly is influenced by numerous factors including the extent of tricuspid leaflet distortion and regurgitation, the degree of pulmonary stenosis, RA pressure, right heart size, and the presence of a right-to-left shunt. More than 50% of patients have a shunt at the atrial level with either a PFO or secundum ASD. Tricuspid valve repair or replacement is recommended by the AHA for the following indications:
Reference:
Warnes CA, Williams RG, Bashore TM, et al. ACC/AHA 2008 guidelines for the management of adults with congenital heart disease: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Writing Committee to Develop Guidelines on the Management of Adults with Congenital Heart Disease). Circulation. 2008;118:e714–e833.
The most common problem in adults with surgically repaired TOF is:
Pulmonary regurgitation. TOF comprises:
Primary repair in the first year of life consists of VSD closure and relief of RVOT obstruction, the latter achieved by increasing the RVOT diameter through patch augmentation or placement of a transannular patch. The integrity of the pulmonary valve is frequently disrupted at the time of repair and predisposes patients to pulmonary regurgitation, the most common residual abnormality seen in adults with repaired TOF.
Although less common than pulmonary regurgitation, ventricular tachycardia is an important cause of late mortality in adults with repaired TOF. TOF patients at highest risk for ventricular tachycardia and sudden death include those with significant residual pulmonary regurgitation/RVOT obstruction, reduced RV or LV function, QRS duration >180 milliseconds, high-grade ectopy on Holter monitoring, and inducible ventricular tachycardia.
A 34-year-old gentleman reports a history of TOF, Blalock-Taussig shunt at 10 months, and complete repair at age 3. Although he has been reasonably active for several years, he has noted progressive exercise intolerance in recent months. Examination reveals a III/VI systolic ejection murmur loudest at the second left intercostal space and a II/IV diastolic murmur along the left sternal edge. Jugular venous pulse is not elevated. Lungs are clear and there is no hepatomegaly or peripheral edema. An echocardiogram demonstrates RV dilatation, moderate-to-severe pulmonic regurgitation but no significant TR. The ECG shows sinus rhythm and right bundle branch block with a QRS duration of 160 milliseconds.
The most reasonable next step in the evaluation of this patient would be:
Cardiac magnetic resonance imaging study. Pulmonary valve replacement is recommended in adults with repaired TOF, severe pulmonary regurgitation, and any of the following:
Surgery in adults with repaired TOF may also be considered for residual RVOT obstruction (peak gradient >50 mmHg), residual VSD with shunt greater than 1.5:1, and severe aortic regurgitation with associated symptoms or more than mild LV dysfunction.
Due to the complex geometry of the RV and limitations of echocardiography, cardiac magnetic resonance imaging is the gold standard investigation for assessment of RV dimensions and function in repaired TOF. Further evaluation of pulmonary regurgitation is also possible. A positive bubble study would be helpful in confirming the presence of an ASD but would not help in deciding timing of pulmonary valve replacement. An ASD is unlikely to explain the degree of RV dilatation seen in this patient, particularly in the presence of a clear etiology (severe pulmonary regurgitation). Formal electrophysiologic testing is not indicated in TOF patients without a history of presyncope or palpitations. Invasive hemodynamics would not provide additional diagnostic or prognostic information. Since there is no evidence of volume overload, the initiation of diuretics and digoxin would not be recommended.
A 35-year-old man is referred for evaluation of dyspnea and a loud cardiac murmur. Examination reveals an RV lift, a palpable systolic thrill at the second left intercostal space, and a widely split second heart sound. There is a loud and harsh ejection systolic murmur heard loudest at the second left intercostal space. BP is 130/80 mmHg, HR 90 bpm, and regular, oxygen saturation 98% on room air.
What is the most likely diagnosis?
Pulmonary stenosis. The clinical findings (RV lift, a palpable systolic thrill at the second left intercostal space, a widely split second heart sound, and harsh ejection systolic murmur heard loudest at the second left intercostal space) are consistent with significant pulmonary stenosis. The RV lift is evidence of a pressure-loaded RV. The second heart sound is split due to delayed closure of the pulmonary valve. Pulmonary valve stenosis is heard loudest at the second left intercostal space and may be associated with a palpable thrill.