I Arterial ductus arteriosus
PDA is one of the most common congenital heart diseases, and its incidence accounts for 15% to 21% of congenital heart diseases, and is twice as common in females as in males, with one PDA occurring in every 2,500 to 5,000 surviving newborns. The current indications for PDA occlusion are: PDA of all types with left-to-right shunts aged ≥3 months and weighing more than 3 kg, without a comorbid cardiac malformation requiring surgical treatment. The vast majority of PDA patients can be cured by interventional methods, but in recent years, the common complications of PDA occlusion have been reported from time to time, how to reasonably carry out PDA occlusion in clinical practice?
1, the correct choice of interventional treatment indications
For infants and children and patients with severe pulmonary hypertension must be cautious, for the inner diameter is greater than the aortic internal diameter of the child should choose surgical treatment, in order to achieve more safe and reliable results; PDA diameter of 10 mm or more should be preferred to domestic blocker, which has a large variety of models, and has a strong umbrella polyethylene sheeting flow blocking effect, not easy to appear residual shunt; for severe pulmonary hypertension For large PDA with severe pulmonary hypertension, the muscle septal blocking umbrella should be used to prevent the blocking umbrella from falling off due to the transient increase in pulmonary artery pressure caused by postoperative patient coughing; when blocking PDA with larger internal diameter, the repeated release and recovery of the blocking umbrella should be avoided to avoid causing pulmonary artery entrapment; after surgical recanalization of PDA, due to local tissue adhesion and fibrosis and scar formation, the wall elasticity is poor, the extensibility is small and The diameter of the blocking umbrella should be larger than the narrowest diameter of the recanalization 2-3mm, but not too large, so as not to cause aortic arch or pulmonary artery stenosis; for PDA patients older than 50 years old or with a history of angina pectoris, coronary angiography should be performed first.
2.Strictly standardize the operation to avoid complications
In order to avoid vascular damage at the puncture site, the transmission sheath should be as thin as possible, and the vein puncture port can be enlarged gradually by using incremental inner sheaths to prevent the large sheaths from causing endothelial coiling, spasm, and fracture of the vein, and postoperative swelling, bruising, and pain in the lower extremities; infants and children have greater elasticity. If the pressure difference is >10mmHg, the aortic lumen stenosis should be considered, and the blocking umbrella should be withdrawn, and the umbrella should be reselected or placed into an angled mushroom umbrella; when When the differential pressure in the pulmonary artery is >5mmHg and the Doppler echocardiogram shows that the flow velocity of the left pulmonary artery exceeds 1.5m/s, the position of the blocking parachute should be adjusted to avoid excessive pulling toward the pulmonary artery end when placing the parachute, which may cause stenosis at the opening of the left pulmonary artery of medical origin. When the blocking device is dislodged to the pulmonary artery, it can be removed by foreign body clamp or mesh basket catheter first, and then surgically if it is unsuccessful. For the blocking parachute dislodged to the arterial side, the internal diameter of the femoral artery should be considered first to avoid damage to the femoral artery in young patients during removal. The complications can be avoided by strictly standardizing the operation and choosing the appropriate blocking device during the intervention.
3. Correct evaluation of the nature of pulmonary hypertension is the key to the decision of interventional indications
When a patient has pulmonary hypertension, it is important to choose the treatment. Patients with pulmonary circulation flow (Qp) / body circulation flow (Qs) >1.3 and arterial oxygen saturation ≥90% on cardiac catheterization can be considered for interventional treatment. Alternatively, experimental occlusion can be used first, and changes in pulmonary and aortic pressures and arterial oxygen saturation can be closely monitored to speculate whether the pulmonary vascular lesion is reversible. At this point, there are 3 conditions.
(1) If the pulmonary artery pressure decreases by 20% or drops by 30 mm Hg (1 mmHg=0.133 kPa) or more, the aortic pressure and arterial oxygen saturation do not decrease or increase, and there is no systemic reaction, the blocking umbrella can be released and permanent blocking can be performed when the blocker position is confirmed to be appropriate by imaging.
( 2) If the pulmonary artery pressure rises, or the aortic pressure falls, and the patient has palpitations, shortness of breath, irritability, blood pressure drops and other obvious systemic reactions, the blocker should be withdrawn immediately and treated symptomatically.
(3) If there is no change in pulmonary artery pressure, no systemic reaction, no decrease in oxygen saturation and cardiac output after experimental blocking, it is impossible to determine whether the pulmonary vascular lesion is reversible and it is difficult to predict the prognosis, so the patient and relatives should be informed of the condition and consent should be obtained before releasing the blocking umbrella.
Atrial septal defect
Atrial septal defect accounts for about 10%-20% of precordial disease, mainly seen in young children and children, most patients develop symptoms only after adolescence, especially after 35 years of age, if not treated in time, pulmonary hypertension will appear, at this time the right ventricle is subjected to left-to-right shunt flow and pulmonary hypertension, so that the right ventricular volume and pressure double overload. With the development of the disease, the patient will experience changes in left ventricular function, which will further aggravate the disease. 1997 saw the invention of the double-disc nickel-titanium alloy blocker, and the efficacy of percutaneous catheter application of the blocker in treating secondary holes has been confirmed, and interventional therapy has become the treatment of choice for ASD.
The indications for interventional treatment of ASD as stipulated in the Guidelines for Transcatheter Interventional Treatment of Congenital Heart Disease formulated by the Chinese Medical Association in 2003 are as follows
(1) Age: usually ≥3 years.
(2) ASD with a diameter of ≥5 mm with increased right heart volume load, ≤36 mm secondary to a foramen ovale with left-to-right shunt.
( 3) Distance from the edge of the defect to the coronary sinus, superior and inferior vena cava, and pulmonary veins ≥ 5 mm, and from the atrioventricular valve ≥ 7 mm.
( 4) The diameter of the atrial septum is larger than the diameter of the left atrial lateral umbilical selected for blocking.
( 5) No other cardiac malformation requiring surgery.
( 6) Post-surgical residual shunt.
Over the past decade of ASD intervention, cases and experience have been accumulated and indications have been broadened, while there are new insights into ASD intervention.
1, patients should be treated as early as possible
The long-term survival rate of those who underwent surgery before the age of 24 was the same as that of normal controls of the same age and gender,
The long-term survival rate for those who undergo surgery after the age of 40 is only 40% of normal, and the incidence of atrial fibrillation increases. Therefore, for adult patients with or without symptoms, as long as there is evidence of right ventricular volume loading on ultrasonography, they should be closed as soon as possible.
2. With severe pulmonary hypertension
If the ratio of pulmonary artery pressure to aortic pressure is less than 0.8, after balloon occlusion, the measured pulmonary artery pressure decreases by more than 20%, while the aortic pressure does not decrease or decreases insignificantly, the oxygen saturation increases by more than 90% and the tricuspid regurgitation decreases, it means that the pulmonary vascular bed is reactive and interventional treatment can be performed.
3. With left heart insufficiency
ASD patients due to long-term right ventricular volume load so that the left ventricular pressure can not be fully filled, the lack of exercise of the left ventricular myocardium, while the apoptosis of myocardial cells, the left heart function will be damaged to varying degrees, after blocking, the left ventricular volume load of the sharp increase, the left ventricle can not compensate, there will be chest tightness, inspiratory difficulties and other signs of left heart insufficiency, and even fatal pulmonary edema, it is generally believed that the average pressure rise of the left atrium greater than It is generally believed that a rise in mean left atrial pressure greater than 10 mmHg is potentially left heart insufficiency and should be prevented by drugs such as tachycardia, dobutamine and milrinone.
4. ASD size, margin and blocker selection
The indications for interventional treatment are that the defect diameter is between 5-36 mm and there are sufficient margins around it (>5 mm). However, blockers and similar domestic blockers are designed so that they may be used to block defects with partial lack of margins or margins <5 mm. It is generally believed that this type of ASD can be fully treated with intervention if the posterior margin is sufficient and a slightly larger blocker than the maximum diameter of the defect is chosen, while a weak or lacking posterior margin often suggests a larger defect extension diameter, and this type of intervention requires a high level of skill and experience from the operator, including the ultrasonographer. If one blocker can not completely block the defect, double balloons should be used to measure the two defects at the same time. If the spacing is small, in principle, the small defect should be blocked first and the large defect should be blocked later, and the large umbrella should be clamped to the small umbrella.
Ventricular septal defect
Ventricular septal defect is one of the most common congenital intracardiac malformations, accounting for about 25% of congenital heart disease. Surgical procedures are the traditional treatment method, and with the development of technology, the success rate has improved significantly and the complications have gradually decreased, however, there are disadvantages such as large surgical trauma, long recovery time and scar left on the body surface. Transcatheter intervention can achieve similar efficacy, but with less trauma and lower complication rate, and has become the preferred treatment for patients with indications.
1. Indications
(1)Diameter of the defect: the diameter of the left ventricular surface of the perimembranous defect is 3-12mm; if the right ventricular side is porous, the diameter of the large hole should be greater than 2mm; if it is accompanied by a concurrent membrane tumor, the diameter of the left ventricular surface of the defect is 13-18mm as a relative indication, requiring the right ventricular surface to have a small exit and its adhesions are firm.
(2) The distance between the defect edge of the perimembranous part and the right coronary valve of the aorta: eccentric blocker >1.5 mm, symmetric blocker >2.0 mm.
(3) Distance between the defect edge and the right atrioventricular valve: eccentric blocker >2mm, symmetric blocker >1.5mm.
(4) Combination of other cardiovascular malformations that can be treated by intervention.
(5) Residual leak after surgical procedure.
(6) Mild to moderate pulmonary hypertension without right-to-left shunt.
(7) Myocardial VSD combined with acute myocardial infarction or trauma-induced myocardial VSD.
(8) Age greater than 3 years and weight greater than 10 kg.
2.Individualized blocking device selection
Generally speaking, the myocardial VSD is mainly blocked with a myocardial VSD blocker. For myocardial VSD with a large left ventricular surface and a small right ventricular surface, it may be more reasonable to choose a PDA blocker; eccentric blockers are chosen for crestal VSD; the choice of blockers for membranous VSD is very complicated, and symmetrical, asymmetrical (small waist and large edge) and eccentric blockers can be chosen, mainly according to the size of the defect, the edge condition, the distance from the aortic valve, the tricuspid valve, the tricuspid valve and the tricuspid valve. It is determined by the size of the defect, the margin, the distance from the aortic valve, the tricuspid valve, the shape of the defect, and the relationship between the size of the entrance and exit. In addition to complete blocking of the VSD, the choice of the blocker should be based on the morphology of the blocker. Under fluoroscopy, the two discs of the blocker should be fully extended, flat, and maintain their initial shape in vitro, with the stainless steel fixation ring on the right ventricular side inside the concave surface and slightly protruding from the outer side of the blocker disc. Ultrasound showed that the blocker was short in length and tightly attached to the sides of the septum. Blindly increasing the diameter of the blocker may increase the risk of postoperative conduction block.
3.Selection of blocker with membranous tumor or porous type
It is difficult to choose the blocker for combined membranous tumor, and there is no consensus on the choice of blocker and whether it is better to block the exit or entrance.