Data and methods
1 Data: 2 males and 3 females, aged 23-38 years, weight (45-67) kg, with symptoms of “palpitations and chest tightness”, 2 cases of “right ventricular hypertrophy”, 1 case of “incomplete right bundle branch block” and 2 cases of “left ventricular hypertrophy” on electrocardiogram. Two cases of “right ventricular hypertrophy”, one case of “incomplete right bundle branch conduction block” and two cases of “left ventricular hypertrophy” on ECG: the cardiothoracic ratio (C/T) ranged from 0.55 to 0.63 (mean 0.58±0.03): the echocardiogram showed that the VSD was perimembranous and subcricoid, the VSD diameter (1.8-2.5) cm, the PDA diameter (1.0-1.5 The mean pulmonary artery pressure (MPAP) was 69±8 mmHg. The patients were treated with oral cardiotonic, diuretic, sildenafil, and intravenous sodium nitroprusside and prostil to lower the pulmonary artery pressure. Pang Yunfeng, Department of Cardiac Surgery, Qinghai Provincial Specialist Hospital of Cardiovascular Diseases
2 Methods Phase I treatment was performed in the interventional catheterization laboratory with PDA interventional blocking treatment. Patients were punctured through the arterial and femoral veins under local anesthesia and a 6F sheath was placed, and descending aortography was performed to determine the size, shape and location of the PDA. Then a multifunctional catheter was delivered through the femoral vein sheath to the right atrium, and the catheter was manipulated to enter the right ventricle and pulmonary artery through the tricuspid valve. The pressure of the main pulmonary artery and the right and left pulmonary arteries were measured, blood gas was drawn to determine the oxygen level, and the pulmonary-to-systemic flow ratio (Qp/Qs) and total pulmonary resistance (PVR) were calculated. The blocking parachute of suitable size was selected (2 mm to 4 mm larger than the narrowest part of the PDA). 3 cases of 16 (14) mm blocking parachute and 2 cases of 18 (16) mm blocking parachute were selected in this group and sent to the descending aorta via the delivery sheath. The blocker is released after satisfactory assessment by descending aortography again. Repeat the cardiac catheterization, and calculate the mean pulmonary artery pressure, Qp/Qs and total pulmonary artery resistance after successful blocking again. The sheath was withdrawn and returned to the ward with local pressure dressing to stop the bleeding. The mean pulmonary artery pressure, Qp/Qs, and total pulmonary artery resistance all decreased to different degrees after the intervention was performed. Oral cardiotonic, diuretic, and pulmonary artery pressure-lowering drugs were continued postoperatively.
Phase II treatment was performed 3-6 months after phase I treatment. Under general anesthesia, a median thoracic incision was made, extracorporeal circulation was established, and the circulation was blocked when the whole body was cooled to 28°C-30°C. Autologous pericardial slices were applied, and 4-0 polypropylene thread (prolene) was used to repair the ventricular septal defect with continuous sutures. After interruption of extracorporeal circulation, the ratio of aortic pressure and pulmonary artery pressure was measured, and the mean pulmonary artery pressure decreased to (32±8) mm Hg. After the operation, the patient was returned to the monitoring room, and postoperative treatment with sodium nitroprusside and prostilbestrol to lower the pulmonary artery pressure and prolong the ventilator assist time was given to prevent the occurrence of pulmonary hypertension crisis.
After discharge, oral cardiotonic and diuretic drugs and sildenafil were continued to lower pulmonary arterial pressure. Postoperative follow-up was performed at 1, 3, 6 months and 1 year, and electrocardiogram and echocardiogram were checked to observe rhythm changes, blocker morphology, the presence of residual shunt and pulmonary arterial pressure decrease.
Results
The mean intervention time of PDA was (42±9) min, the success rate of blocking was 100%, the hospitalization time of phase I treatment was (6-8) days, and phase II treatment was performed after phase I treatment (3-6) months. 5 patients had no other postoperative complications, and no right heart failure or death occurred after discharge.
After discharge, oral cardiotonic and diuretic drugs and sildenafil were continued to lower pulmonary artery pressure. 1, 3, 6 months and 1 year postoperative follow-up were performed to check electrocardiogram and echocardiogram to observe symptoms, rhythm changes, blocker morphology, the presence of residual shunt and pulmonary artery pressure decrease. right heart failure and death did not occur in all patients during the follow-up.
DISCUSSION
Many patients with VSD and PDA come to the clinic after the onset of symptoms and are often combined with moderate to severe pulmonary arterial hypertension, so the method and timing of surgery are very important for these patients. Since the advent of interventional occlusion therapy, simple PDA occlusion therapy has become the first choice for the treatment of PDA, and some VSD can also be treated by intervention. We selected patients with VSD and PDA combined with severe pulmonary hypertension who could not undergo interventional therapy at the same time, and we tried a combination of staged PDA interventional therapy and VSD surgical treatment, and conducted follow-up, and achieved good treatment results. We have the following experience: ①, the first stage of PDA interventional blocking treatment, interventional treatment has the characteristics of short time, small trauma, fast recovery, etc. At the same time, the interventional treatment can also measure the pulmonary artery pressure and perform cardiac catheterization, which provides a basis for determining the indication for surgery and further treatment. We strictly measured the ratio of pulmonary artery pressure and aortic pressure during PDA blocking, and then performed PDA trial blocking to observe whether the pulmonary artery pressure and right ventricular pressure would rise, and whether the aortic pressure and oxygen saturation would fall, and performed cardiac catheterization to identify whether it was dynamic pulmonary hypertension or resistance pulmonary hypertension, and then decided to release the blocker. The degree of reduction is significant, suggesting that it is dynamic pulmonary hypertension, which can be treated by interventional therapy and second-stage surgery, we choose second-stage surgery treatment after 3-6 months of first-stage treatment, during which oral cardiotonic and diuretic drugs and sildenafil lowering pulmonary artery pressure treatment are given to make second-stage treatment safer: ②, second-stage surgery for VSD, because it reduces the time required to perform PDA closure under extracorporeal circulation, greatly saving the operation time and avoiding complications The time required for PDA closure under extracorporeal circulation is reduced, which greatly saves the operation time and avoids the chance of complications.
Selection of indications for staged composite therapy: Patients with intracardiac shunts or arterial shunts with right-to-left shunts cannot be treated with staged composite therapy because they have developed resistance pulmonary hypertension and Eisenmenger syndrome, which are contraindications to surgery. For patients with VSD with small PDA, it is not necessary to perform staged composite therapy, and simultaneous surgery is a definitive treatment method with low surgical risk. patients with VSD with PDA, combined with severe pulmonary hypertension, have coarse PDA, we measure the ratio of pulmonary artery pressure to aortic pressure during PDA occlusion, perform PDA trial occlusion, observe whether pulmonary artery pressure and right ventricular pressure will rise, and whether aortic pressure and oxygen saturation will fall. Oxygen saturation will decrease, and cardiac catheterization will be performed to identify whether it is power pulmonary hypertension or resistance pulmonary hypertension. In this group of patients, postoperative pulmonary artery pressure and pulmonary circulatory resistance both decreased significantly, suggesting power pulmonary hypertension, suggesting that staged composite therapy can be performed. Postoperatively, patients should pay attention to rest, avoid strenuous activities, and continue pulmonary artery pressure lowering therapy.
In conclusion, the staged treatment of VSD with PDA, combined with severe pulmonary hypertension by interventional occlusion therapy plus elective surgery is safe and effective, and can be the treatment of choice for such patients, and only by strictly mastering the indications can we provide effective treatment for more patients.