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Each of the symptoms of situs ambiguous must be managed with appropriate treatment dependent upon the organ system involved. Intestinal malrotation is treated surgically using the Ladd procedure. This procedure widens a fold in the peritoneum so that the intestines can be placed in non-rotated formation. Unfortunately, it is not possible to return the bowel to a normal morphology However, 89% of patients that undergo the Ladd surgery experience a complete resolution of symptoms.
Following cholangiogram, a Kasai Procedure is usually performed in cases of biliary atresia. In this surgery, a Y-shaped shunt is used to passage bile from the liver directly to the intestine. If this is unsuccessful, liver transplantation can be considered based on the overall health of the patient. Fortunately, the Kasai Procedure is successful in approximately 80% of patients. Following the operation, patients are advised to take fat-soluble vitamins, choleretics, and anti-inflammatory medications.
Functionally asplenic patients have an elevated lifetime risk of septicemia, as they have no functional spleen for fighting infection. For this reason, asplenic patients are under constant observation for any signs of fever or infection. In the case of infection, patients are placed on controlled empiric antibiotic therapy to avoid development of antibiotic resistance. This therapy battles infection by both gram-positive and gram-negative bacteria.
Right-atrial and left-atrial isomerism and associated pulmonary issues are treated in a series of steps based on the severity of symptoms. Isomeric patients are first treated by inserting a shunt that will move incoming blood through the pulmonary circuit. The Fontan procedure routes blood through the patient's single ventricle, to the lungs, and into systemic circulation. This process is favorable in patients aged 2 – 5 years old. Unfortunately, 20-30% of patients will require a heart transplant. Left-atrial isomeric patients have less severe complications, as they typically have 2 functional ventricles. In this case, they can undergo biventricular repair to form 2 separate ventricles and functional associated valves.
Prognosis for patients with situs ambiguous is quite varied, considering the spectrum of clinical complications. Infants who experience severe cyanosis at birth die within hours of delivery if medical intervention is not immediate. Alternatively, longevity of neonates with mild cardiac lesions is unaffected. Ten percent of patients born with right atrial isomerism die by the age of 5 without intervention. Fortunately, improvements in therapies has increased the 5-year survival to 30-74% for right atrial isomeric patients and 65-84% for left atrial isomeric patients based on the cause of their disease.
Surgical treatment involves resection of the stenosed segment and re-anastomsis. Two complications specific to this surgery are Left recurrent nerve palsy and chylothorax, as the recurrent laryngeal nerve and thoracic duct are in the vicinity. Chylothorax is a troublesome complication and is usually managed conservatively by adjusting the diet to eliminate long chain fatty acids and supplementing medium chain triglycerides. When conservative management fails surgical intervention is required. Fluorescein dye can aid in the localisation of chyle leak.
Pharmacologic management of ARVD involves arrhythmia suppression and prevention of thrombus formation.
Sotalol, a beta blocker and a class III antiarrhythmic agent, is the most effective antiarrhythmic agent in ARVD. Other antiarrhythmic agents used include amiodarone and conventional beta blockers (i.e.: metoprolol). If antiarrhythmic agents are used, their efficacy should be guided by series ambulatory holter monitoring, to show a reduction in arrhythmic events.
While angiotensin converting enzyme inhibitors (ACE Inhibitors) are well known for slowing progression in other cardiomyopathies, they have not been proven to be helpful in ARVD.
Individuals with decreased RV ejection fraction with dyskinetic portions of the right ventricle may benefit from long term anticoagulation with warfarin to prevent thrombus formation and subsequent pulmonary embolism.
Treatment is not necessary in asymptomatic patients.
The treatment options for mitral stenosis include medical management, mitral valve replacement by surgery, and percutaneous mitral valvuloplasty by balloon catheter.
The indication for invasive treatment with either a mitral valve replacement or valvuloplasty is NYHA functional class III or IV symptoms.
Another option is balloon dilatation. To determine which patients would benefit from percutaneous balloon mitral valvuloplasty, a scoring system has been developed. Scoring is based on 4 echocardiographic criteria: leaflet mobility, leaflet thickening, subvalvar thickening, and calcification. Individuals with a score of ≥ 8 tended to have suboptimal results. Superb results with valvotomy are seen in individuals with a crisp opening snap, score < 8, and no calcium in the commissures.
Treatment also focuses on concomitant conditions often seen in mitral stenosis:
- Any angina is treated with short-acting nitrovasodilators, beta-blockers and/or calcium blockers
- Any hypertension is treated aggressively, but caution must be taken in administering beta-blockers
- Any heart failure is treated with digoxin, diuretics, nitrovasodilators and, if not contraindicated, cautious inpatient administration of ACE inhibitors
In adults and children found to have coarctation, treatment is conservative if asymptomatic, but may require surgical resection of the narrow segment if there is arterial hypertension. The first operations to treat coarctation were carried out by Clarence Crafoord in Sweden in 1944. In some cases angioplasty can be performed to dilate the narrowed artery, with or without the placement of a stent graft.
For fetuses at high risk for developing coarctation, a novel experimental treatment approach is being investigated, wherein the mother inhales 45% oxygen three times a day (3 x 3–4 hours) beyond 34 weeks of gestation. The oxygen is transferred via the placenta to the fetus and results in dilatation of the fetal lung vessels. As a consequence, the flow of blood through the fetal circulatory system increases, including that through the underdeveloped arch. In suitable fetuses, marked increases in aortic arch dimensions have been observed over treatment periods of about two to three weeks.
The long term outcome is very good. Some patients may, however, develop narrowing (stenosis) or dilatation at the previous coarctation site. All patients with unrepaired or repaired aortic coarctation require follow up in specialized Congenital Heart Disease centers.
In terms of treatment for tricuspid insufficiency prosthetic valve substitutes can be used, though artificial prostheses may cause thrombo‐embolic phenomena(bioprostheses may have a degeneration problem). Some evidence suggests that there are no significant differences between a mechanical or biological tricuspid valve in a recipient.
Generally, surgical treatment of tricuspid regurgitation is not indicated when it has arisen as a result of right ventricular dilatation. In such instances of secondary tricuspid regurgitation, the mainstay of therapy is medical. When left-sided heart failure is the cause, the individual is instructed to decrease intake of salt. Medications in this case may include diuretics and angiotensin-converting enzyme inhibitors.
The treatment of mitral insufficiency depends on the acuteness of the disease and whether there are associated signs of hemodynamic compromise.
In acute MI secondary to a mechanical defect in the heart (i.e., rupture of a papillary muscle or chordae tendineae), the treatment of choice is mitral valve surgery. If the patient is hypotensive prior to the surgical procedure, an intra-aortic balloon pump may be placed in order to improve perfusion of the organs and to decrease the degree of MI.
If the individual with acute MI is normotensive, vasodilators may be of use to decrease the afterload seen by the left ventricle and thereby decrease the regurgitant fraction. The vasodilator most commonly used is nitroprusside.
Individuals with chronic MI can be treated with vasodilators as well to decrease afterload. In the chronic state, the most commonly used agents are ACE inhibitors and hydralazine. Studies have shown that the use of ACE inhibitors and hydralazine can delay surgical treatment of mitral insufficiency. The current guidelines for treatment of MI limit the use of vasodilators to individuals with hypertension, however. Any hypertension is treated aggressively, e.g. by diuretics and a low-sodium diet. In both hypertensive and normotensive cases, digoxin and antiarrhythmics are also indicated. Also, chronic anticoagulation is given where there is concomitant mitral valve prolapse or atrial fibrillation. In general, medical therapy is non-curative and is used for mild-to-moderate regurgitation or in patients unable to tolerate surgery.
Surgery is curative of mitral valve regurgitation. There are two surgical options for the treatment of MI: mitral valve replacement and mitral valve repair. Mitral valve repair is preferred to mitral valve replacement where a repair is feasible as bioprosthetic replacement valves have a limited lifespan of 10 to 15 years, whereas synthetic replacement valves require ongoing use of blood thinners to reduce the risk of stroke. There are two general categories of approaches to mitral valve repair: Resection of the prolapsed valvular segment (sometimes referred to as the 'Carpentier' approach), and installation of artificial chordae to "anchor" the prolapsed segment to the papillary muscle (sometimes referred to as the 'David' approach). With the resection approach, any prolapsing tissue is resected, in effect removing the hole through which the blood is leaking. In the artificial chordae approach, ePTFE (expanded polytetrafluoroethylene, or Gore-Tex) sutures are used to replace the broken or stretched chordae tendonae, bringing the natural tissue back into the physiological position, thus restoring the natural anatomy of the valve. With both techniques, an annuloplasty ring is typically secured to the annulus, or opening of the mitral valve, to provide additional structural support. In some cases, the "double orifice" (or 'Alfieri') technique for mitral valve repair, the opening of the mitral valve is sewn closed in the middle, leaving the two ends still able to open. This ensures that the mitral valve closes when the left ventricle pumps blood, yet allows the mitral valve to open at the two ends to fill the left ventricle with blood before it pumps. In general, mitral valve surgery requires "open-heart" surgery in which the heart is arrested and the patient is placed on a heart-lung machine (cardiopulmonary bypass). This allows the complex surgery to proceed in a still environment.
Due to the physiological stress associated with open-heart surgery, elderly and very sick patients may be subject to increased risk, and may not be candidates for this type of surgery. As a consequence, there are attempts to identify means of correcting MI on a beating heart. The Alfieri technique for instance, has been replicated using a percutaneous catheter technique, which installs a "MitraClip" device to hold the middle of the mitral valve closed.
A surgical treatment for AI is aortic valve replacement; this is currently an open-heart procedure. In the case of severe "acute" aortic insufficiency, all individuals should undergo surgery, if there are no absolute contraindications (for surgery). Individuals with bacteremia with aortic valve endocarditis should not wait for treatment with antibiotics to take effect, given the high mortality associated with the acute AI. Replacement with an aortic valve homograft should be performed if feasible.
Catheter ablation may be used to treat intractable ventricular tachycardia.
It has a 60–90% success rate. Unfortunately, due to the progressive nature of the disease, recurrence is common (60% recurrence rate), with the creation of new arrhythmogenic foci. Indications for catheter ablation include drug-refractory VT and frequent recurrence of VT after ICD placement, causing frequent discharges of the ICD.
Indications for surgery for chronic MI include signs of left ventricular dysfunction with ejection fraction less than 60%, severe pulmonary hypertension with pulmonary artery systolic pressure greater than 50 mmHg at rest or 60 mmHg during activity, and new onset atrial fibrillation.
Mitral valvuloplasty is a minimally invasive therapeutic procedure to correct an uncomplicated mitral stenosis by dilating the valve using a balloon.
Under local anaesthetic, a catheter with a special balloon is passed from the right femoral vein, up the inferior vena cava and into the right atrium. The interatrial septum is punctured and the catheter passed into the left atrium using a "trans-septal technique." The balloon is sub-divided into 3 segments and is dilated in 3 stages. First, the distal portion (lying in the left ventricle) is inflated and pulled against the valve cusps. Second, the proximal portion is dilated, in order to fix the centre segment at the valve orifice. Finally, the central section is inflated, this should take no longer than 30 seconds, since full inflation obstructs the valve and causes congestion, leading to circulatory arrest and flash pulmonary edema.
With careful patient pre-selection, percutaneous balloon mitral valvuloplasty (PBMV) is associated with good success rates and a low rate of complications. By far the most serious adverse event is the occurrence of acute severe mitral regurgitation. Severe mitral regurgitation usually results from a tear in one of the valve leaflets or the subvalvular apparatus. It can lead to pulmonary edema and hemodynamic compromise, necessitating urgent surgical mitral valve replacement.
Other serious complications with PBMV usually relate to the technique of trans-septal puncture (TSP). The ideal site for TSP is the region of the fossa ovalis in the inter-atrial septum. Occasionally, however, the sharp needle used for TSP may inadvertently traumatize other cardiac structures, leading to cardiac tamponade or serious blood loss.
Although the immediate results of PBMV are often quite gratifying, the procedure does not provide permanent relief from mitral stenosis. Regular follow-up is mandatory, to detect restenosis. Long-term follow-up data from patients undergoing PBMV indicates that up to 70-75% individuals can be free of restenosis 10 years following the procedure. The number falls to about 40% 15 years post-PBMV.
Medical therapy of chronic aortic insufficiency that is stable and asymptomatic involves the use of vasodilators. Trials have shown a short term benefit in the use of ACE inhibitors or angiotensin II receptor antagonists, nifedipine, and hydralazine in improving left ventricular wall stress, ejection fraction, and mass. The goal in using these pharmacologic agents is to decrease the afterload so that the left ventricle is somewhat spared. The regurgitant fraction may not change significantly, since the gradient between the aortic and left ventricular pressures is usually fairly low at the initiation of treatment. Other rather conservative medical treatments for stable and asymptomatic cases include low sodium diet, diuretics, digoxin, calcium blockers and avoiding very strenuous activity.
As of 2007, the American Heart Association no longer recommends antibiotics for endocarditis prophylaxis before certain procedures in patients with aortic insufficiency. Antibiotic prophylaxis to prevent endocarditis before gastrointestinal or genitourinary procedures is no longer recommended for any patient with valvular disease. Cardiac stress test is useful in identifying individuals that may be best suited for surgical intervention. Radionuclide angiography is recommended and useful when the systolic wall stress is calculated and combined to the results.
Individuals with mitral valve prolapse, particularly those without symptoms, often require no treatment. Those with mitral valve prolapse and symptoms of dysautonomia (palpitations, chest pain) may benefit from beta-blockers (e.g., propranolol). Patients with prior stroke and/or atrial fibrillation may require blood thinners, such as aspirin or warfarin. In rare instances when mitral valve prolapse is associated with severe mitral regurgitation, mitral valve repair or surgical replacement may be necessary. Mitral valve repair is generally considered preferable to replacement. Current ACC/AHA guidelines promote repair of mitral valve in patients before symptoms of heart failure develop. Symptomatic patients, those with evidence of diminished left ventricular function, or those with left ventricular dilatation need urgent attention.
Simple surgical excision is curative. The recommended treatment is that the skin is peeled off the extra-auricular tissue and protruding cartilage remnants are trimmed. Normal appearance is achieved in majority of cases. The reconstruction successful in true cases of accessory auricle, as it also is in individuals with auricular appendages.
Drug therapy can slow down progression and in some cases even improve the heart condition. Standard therapy may include salt restriction, ACE inhibitors, diuretics, and beta blockers. Anticoagulants may also be used for antithrombotic therapy. There is some evidence for the benefits of coenzyme Q10 in treating heart failure.
Artificial pacemakers may be used in patients with intraventricular conduction delay, and implantable cardioverter-defibrillators in those at risk of arrhythmia. These forms of treatment have been shown to prevent sudden cardiac death, improve symptoms, and reduce hospitalization in patients with systolic heart failure.
The treatment for cor pulmonale can include the following: antibiotics, expectorants, oxygen therapy, diuretics, digitalis, vasodilators, and anticoagulants. Some studies have indicated that Shenmai injection with conventional treatment is safe and effective for cor pulmonale (chronic).
Treatment requires diuretics (to decrease strain on the heart). Oxygen is often required to resolve the shortness of breath. Additionally, oxygen to the lungs also helps relax the blood vessels and eases right heart failure. When wheezing is present, the majority of individuals require a bronchodilator. A variety of drugs have been developed to relax the blood vessels in the lung, calcium channel blockers are used but only work in few cases and according to NICE are not recommended for use at all.
Anticoagulants are used when venous thromboembolism is present. Venesection is used in severe secondary polycythaemia (because of hypoxia), which improves symptoms though survival rate has not been proven to increase.Finally, transplantation of single/double lung in extreme cases of cor pulmonale is also an option.
Many factors influence the time course and extent of remodeling, including the severity of the injury, secondary events (recurrent ischemia or infarction), neurohormonal activation, genetic factors and gene expression, and treatment. Medications may attenuate remodeling. Angiotensin-converting enzyme (ACE) inhibitors have been consistently shown to decrease remodeling in animal models or transmural infarction and chronic pressure overload. Clinical trials have shown that ACE inhibitor therapy after myocardial infarction leads to improved myocardial performance, improved ejection fraction, and decreased mortality compared to patients treated with placebo. Likewise, inhibition of aldosterone, either directly or indirectly, leads to improvement in remodeling. Carvedilol, a 3rd generation beta blocker, may actually reverse the remodeling process by reducing left ventricular volumes and improving systolic function. Early correction of congenital heart defects, if appropriate, may prevent remodeling, as will treatment of chronic hypertension or valvular heart disease. Often, reverse remodeling, or improvement in left ventricular function, will also be seen.
Individuals with MVP are at higher risk of bacterial infection of the heart, called infective endocarditis. This risk is approximately three- to eightfold the risk of infective endocarditis in the general population. Until 2007, the American Heart Association recommended prescribing antibiotics before invasive procedures, including those in dental surgery. Thereafter, they concluded that "prophylaxis for dental procedures should be recommended only for patients with underlying cardiac conditions associated with the highest risk of adverse outcome from infective endocarditis."
Many organisms responsible for endocarditis are slow-growing and may not be easily identified on routine blood cultures (these fastidious organisms require special culture media to grow). These include the HACEK organisms, which are part of the normal oropharyngeal flora and are responsible for perhaps 5 to 10% of infective endocarditis affecting native valves. It is important when considering endocarditis to keep these organisms in mind.
The prognosis of tricuspid insufficiency is less favorable for males than females. Furthermore, increased tricuspid insufficiency (regurgitation) severity is an indication of a poorer prognosis according to Nath, et al. It is also important to note that since tricuspid insufficiency most often arises from left heart failure or pulmonary hypertension, the person's prognosis is usually dictated by the prognosis of the latter conditions and not by the tricuspid insufficiency "per se".
Rate control to a target heart rate of less than 110 beats per minute is recommended in most people. Lower heart rates may be recommended in those with left ventricular hypertrophy or reduced left ventricular function. Rate control is achieved with medications that work by increasing the degree of block at the level of the AV node, decreasing the number of impulses that conduct into the ventricles. This can be done with:
- Beta blockers (preferably the "cardioselective" beta blockers such as metoprolol, bisoprolol, or nebivolol)
- Non-dihydropyridine calcium channel blockers (e.g., diltiazem or verapamil)
- Cardiac glycosides (e.g., digoxin) – have less use, apart from in older people who are sedentary. They are not as effective as either beta blockers or calcium channel blockers.
In those with chronic disease either beta blockers or calcium channel blockers are recommended.
In addition to these agents, amiodarone has some AV node blocking effects (in particular when administered intravenously), and can be used in individuals when other agents are contraindicated or ineffective (particularly due to hypotension).
Although its cause is poorly understood, situs ambiguous has been linked to family history of malformations and maternal cocaine use, suggesting both genetic and environmental factors play a role. Several genes in the TGF-beta pathway, which controls left-right patterning of viseral organs across the body axis, have been indicated in sporadic and familial cases of atrial isomerism.
There does not appear to be a screening method for prevention of heterotaxy syndrome. However, genetic testing in family members that display atrial isomerism or other cardiac malformations may help to discern risk for additional family members, especially in X-linked causes of heterotaxy syndrome.
Many of the congenital malformations found with Malpuech syndrome can be corrected surgically. These include cleft lip and palate, omphalocele, urogenital and craniofacial abnormalities, skeletal deformities such as a caudal appendage or scoliosis, and hernias of the umbillicus. The primary area of concern for these procedures applied to a neonate with congenital disorders including Malpuech syndrome regards the logistics of anesthesia. Methods like tracheal intubation for management of the airway during general anesthesia can be hampered by the even smaller, or maldeveloped mouth of the infant. For regional anesthesia, methods like spinal blocking are more difficult where scoliosis is present. In a 2010 report by Kiernan et al., a four-year-old girl with Malpuech syndrome was being prepared for an unrelated tonsillectomy and adenoidectomy. While undergoing intubation, insertion of a laryngoscope, needed to identify the airway for the placement of the endotracheal tube, was made troublesome by the presence of micrognathia attributed to the syndrome. After replacement with a laryngoscope of adjusted size, intubation proceeded normally. Successful general anesthesia followed.
A rare follow-up of a male with Malpuech syndrome was presented by Priolo et al. (2007). Born at term from an uneventful pregnancy and delivery, the infant underwent a surgical repair of a cleft lip and palate. No problems were reported with the procedure. A heart abnormality, atrial septal defect, was also apparent but required no intervention. At age three years, mental retardation, hyperactivity and obsessive compulsive disorder were diagnosed; hearing impairment was diagnosed at age six, managed with the use of hearing aids. Over the course of the decade that followed, a number of psychiatric evaluations were performed. At age 14, he exhibited a fear of physical contact; at age 15, he experienced a severe psychotic episode, characterized by agitation and a loss of sociosexual inhibition. This array of symptoms were treated pharmocologically (with prescription medications). He maintained a low level of mental deficiency by age 17, with moments of compulsive echolalia.
The main goals of treatment are to prevent circulatory instability and stroke. Rate or rhythm control are used to achieve the former, whereas anticoagulation is used to decrease the risk of the latter. If cardiovascularly unstable due to uncontrolled tachycardia, immediate cardioversion is indicated. Regular, moderate-intensity exercise is beneficial for people with AF.
In general, atrial flutter should be managed the same as atrial fibrillation. Because both rhythms can lead to the formation of a blood clot in the atrium, individuals with atrial flutter usually require some form of anticoagulation or antiplatelet agent. Both rhythms can be associated with dangerously fast heart rates and thus require medication to control the heart rate (such as beta blockers or calcium channel blockers) and/or rhythm control with class III antiarrhythmics (such as ibutilide or dofetilide). However, atrial flutter is more resistant to correction with such medications than atrial fibrillation. For example, although the class III antiarrhythmic agent ibutilide is an effective treatment for atrial flutter, rates of recurrence after treatment are quite high (70-90%). Additionally, there are some specific considerations particular to treatment of atrial flutter.