Other Congenital Heart Disease Flashcards
Sinus of valsalva
The sinus of Valsalva aneurysm often involves the right sinus and usually ruptures in the RV, at the age of 15–45. Less frequently, it may arise from the non‐coronary sinus and rupture in the RA.
It usually comes to attention after rupture and manifests as a continuous murmur, predominantly at the right sternal border, and a large left‐to‐right shunt with left HF from the volume overload circulating back to the LV (like VSD),
BUT also right HF from the diastolic shunting into the RV.
It may also lead to coronary compression and myocardial ischemia.
Not infrequently, it may remain asymptomatic.
It is frequently associated with VSD (~50%) and AI (~50%).
Scimitar syndrome
The pulmonary veins of the right upper lobe and most of the right lower lobe empty into the IVC just below the RA
The anomalous right pul monary vein descending to connect with the IVC has the shape of a scimitar and may get compressed as it emerges through the lung
Similar to ASD, the scimitar shunt occurs proximal to the tricuspid valve, is usually small, and does not, by itself, lead to pulmonary hypertension. However, patients with scimitar syndrome have associated anomalies that explain most of the untoward effects and pulmonary hypertension :
• Hypoplasia of the right lung with hypolasia of the right pulmonary artery.
• Branches of the upper abdominal aorta (e.g., celiac artery) or the lower thoracic aorta supply part of the right lung and may lead to pulmonary hypertension and significant left‐to‐right shunting at the PA level.
• Associated congenital heart disease in 20–25% of the cases (ASD, PDA, coarctation of the aorta)
Persistent left SVC
Persistent left SVC is a condition wherein the left innominate vein drains directly into the coronary sinus, leading to the isolated finding of a dilated coronary sinus. Bubbles injected through a left arm vein briskly fill the coronary sinus (which does not normally fill). It is a benign condition per se, found in
Tetralogy of fallot
Tetralogy of Fallot has four components
a. Outlet VSD with right‐to‐left shunt and cyanosis
b. RV outflow obstruction: the major site of obstruction is usually at the subvalvular, infundibular level. In addition, there is often a stenotic, bicuspid pulmonic valve and in 20%, the pulmonic valve is fully closed with no direct pulmonary flow (pulmonary atresia). There may also be a distal pulmonary arterial stenosis, i.e., pulmonary stenosis may be present at multiple levels.
c. Overriding of the aorta over the interventricular septum (<50% of patients) (In the absence of an overriding aorta, the disorder is called partial tetralogy).
d. RV hypertrophy.
e. A fifth component, ASD (secundum ASD or primum ASD/AV canal defect), is seen in 15% of patients (pentalogy of Fallot).
Palliation treatment in tetralogy of fallot :
Blalock–Taussig shunt (subclavian artery to pulmonary artery shunt) or Glenn shunt (SVC to PA shunt).
These shunts increase pulmonary flow and serve as a bridge to a more complete correction. They are used when complete correction is not possible in the neonatal period or when PA is small and underdeveloped from underfilling. The systemic‐to‐PA shunt (e.g., Blalock–Taussig shunt) should not be kept too long, as it may lead to pulmonary hypertension and high‐output LV failure, similarly to PDA
Surgical correction of fallot :
The VSD is closed with a patch. The infundibular muscular stenosis is resected and the RV outflow tract enlarged and patched all the way up to the pulmonic valve. Pulmonic valvotomy is performed in the case of pulmonic stenosis. This can be performed at any age, including the first few months of life. Freedom from late reintervention and normal exercise tolerance are expected in up to 90% of patients
Complications after fallot operation
Patients may present in adulthood with the following complications:
• Severe pulmonary regurgitation is very common and leads to progressive RV enlargement 10–20 years postoperatively. In fact, during surgical repair of tetralogy, the RV outflow is enlarged and patched all the way up to the pulmonic valve, which dilates the valvular annulus and disrupts the valve, making it incompetent; occasionally, the valve is even removed during surgical repair. Pulmonic valve replacement is required whenever severe RV dilatation, RV systolic dysfunction, or exercise limitation occurs.
• Persistent RVOT obstruction.
• Residual VSD with significant left-to-right shunt (this and the preceding two complications require surgical repair).
• Persistent RV dysfunction.
• Dilated aortic root, progressive AI secondary to VSD
• VT, SVT, and sudden cardiac death, especially in the case of a persistent RV dysfunction or a very wide QRS >180 ms. One‐third of late deaths are sudden. ICD is indicated in case of syncope or sustained VT.
Fontan procedure
Fontan procedure
The Fontan procedure is a palliative surgery that redirects the systemic venous return directly to the pulmonary artery without passing through the RV (= atriopulmonary connection) (Figure 18.12). It is performed in patients who have a “functionally single ventricle,” usually associated with cyanosis. This procedure relieves the chronic volume load on the systemic ventricle that is pumping to both the pulmonary and systemic circulations. What is interesting is that blood flows passively to the PA without an interposed RV, as long as the PA pressure is not increased. In a way, humans who have a normal PA pressure may live without RV for many years or decades ; the RV may be forgone for a passive conduit in patients with a normal PA pressure. The venous pressure must be high enough, higher than the pulmonary pres sure, to let blood flow towards the pulmonary artery. The systemic venous pressure is, therefore, elevated chronically and allows forward flow. The RA is chronically and severely enlarged. The procedure cannot be performed in patients with pulmonary hypertension.
Indications of fontan procedure ?
The Fontan procedure is indicated for :
• Tricuspid atresia : RV is hypoplastic and not connected to the RA (tricuspid valve is closed). Blood flows from the RA to the LA through an ASD, then the LV pumps to the PA through a VSD and to the aorta (Figure 18.12). Initially, these patients temporarily receive a Blalock Taussig shunt to increase PA flow, then a bidirectional Glenn procedure, then Fontan.
• Hypoplastic left heart syndrome: the left heart and the proximal aorta are underdeveloped. The RV pumps to the PA and then the aorta through a PDA.
• Double‐inlet single ventricle: double atria and AV valves drain into a single ventricle. In all those complex anomalies, both right‐to‐left and left‐to‐right shunts are present.
Norwood procedure ?
The norwood procedure ?
Hypolasic left heart syndromes
During the Norwood procedure, the surgeon will:
Build a new, larger aorta. The bottom part of the pulmonary artery (which normally goes from the right ventricle to the lungs) is joined with the aorta. This new, bigger aorta now goes from the right ventricle to the body.
Create a shunt (path) to get blood to the lungs. Because the pulmonary artery now goes from the right ventricle to the body, a shunt is needed to take blood to the lungs. The surgeon will use one of these shunts:
a Blaylock-Taussig-Thomas shunt, which moves blood from (and through) the aorta to the lungs.
a Sano shunt, which moves blood from the right ventricle to the pulmonary artery. From the pulmonary artery, the blood goes into the lungs.
Close the patent ductus arteriosus (PDA). Until now, the baby needed the PDA to stay open so blood could flow from the right ventricle to the body. Now that the right ventricle can pump more blood through the new, bigger aorta, the PDA isn’t needed and can be closed.
Make the atrial septal defect (ASD) bigger. This lets more blood with oxygen get back to the right ventricle so it can be pumped out to the body.
Complications of fontan procedure ?
Long‐term complications of fontan procedure :
• Anastomotic obstruction (leads to increased venous pressure and reduced functional capacity).
• AF or atrial flutter is common.
• Ventricular failure.
• Thrombus formation in the RA, the venous system, or the Fontan circuit. Fontan patients frequently receive aspirin or warfarin prophylaxis to prevent thrombotic events.
• Neoaortic dilatation after Norwood, or stenosis at the neoaortic anastomosis (a form of anastomotic coarctation)
• Protein‐losing enteropathy, from the chronically elevated venous pressure, develops in 10% of patients and carries a poor prognosis (50% mortality at 5 years) Eventually, patients with Fontan complications require cardiac transplantation
D-TGA
D‐TGA
In d‐TGA, the aorta originates from the morphological RV (RA–RV–aorta connection), and the pulmonary artery originates from the morphological LV (LA–LV–PA connection) (Figure 18.13).
Some communication must exist between the two systems (ASD usually, sometimes VSD or PDA). These patients are cyanotic and die within the first year if untreated.
Complex TGA is d‐TGA associated with other major congenital abnormalities (PS, VSD).
Treatment of D-TGA ?
Treatment of D-TGA ?
1. Atrial switch (Mustard or Senning procedures)
2. Arterial switch (Jatene procedure) consists of transposing the PA and aorta to their respective ventricles
3. Rastelli procedure is performed in patients with TGA + VSD + subvalvular PS. The LV is connected to the aorta with a patch passing through the VSD, and the RV is connected to the transected PA through a valved conduit.
L-TGA ?
In l‐TGA, or congenitally corrected TGA ?
the LV and RV with their respective valves are transposed (RA–LV–PA circuit on the right, and LA–RV–aorta circuit on the left). The circulation is physiologically corrected but the morphological RV supports the systemic circulation. L‐TGA, when isolated, is well tolerated and may only come to attention in adulthood, at which time the RV and tricuspid valve supporting the systemic circulation start failing, and AV conduction disease frequently appears. The RV is not designed to support the systemic circu lation, as unlike the LV, it has 2-layered rather than 3-layered walls, and even in L-TGA, it receives blood supply from a single coronary artery, RCA, insufficient for a systemic ventricle; in fact, RV coronary flow reserve is impaired and the RV is chronically ischemic in L-TGA. As a result, RV fails and the survival is only ~60% at the age of 30 (worse if severe TR). L-TGA is most commonly associated with other congenital anomalies, such as progressive regurgiation of the systemic (tricuspid) valve or VSD, triggering a diagnosis in childhood.
The letter “d” or “l” corresponds to the location of the RV and aorta, which are always connected in TGA. In d‐TGA (dextro), the RV and aorta are on the right, the arteries are transposed; in l‐TGA (left), the RV and aorta are on the left, the ventricles are transposed. Even in L-TGA, the aorta has anomalous origin that is left and anterior to the PA (unlike the normal origin which is right and posterior). Tricuspid (lowermost) valve continues to be concordant with the RV and helps identify RV on echo.
