Research about short and medium - Term results of transcatheter closure of perimembranous VSD using the symmetrical double - disc device

s only a small hole in the membrane's septum. It is more accurate to call VSD with the perimeter around the membrane, because some VSDs have intact membrane but defects are around the membrane part, so the name pVSD is used more often. This VSD is closely related to the AV conduction path, which passes through the TI ring and follows the lower posterior edge of the defect then divides into the left and right branches. Therefore, when surgery to patch or close the defect with a device, there is a risk of damage to this transmission line. Figure 1.1: Illustration of atrioventricular conduction pathway; and related to pVSD. 1.2. Pathophysiology and clinical characteristics VSD which has no more cardiac defect causes left and right ventricular shunts that increase circulation to the lungs, increase left ventricular volume, and increase PA pressure. The degree of shunting depends on the diameter of the defect and the resistance of PA. In newborns, the PA resistance is high and decreases gradually from the first days after birth and decreases rapidly in the first 4-6 weeks and returns to normal 2-3 months later. However, due to the high PA resistance, it is often not detected by clinical examination in the first months because the left-right shunts are not large enough to generate systolic murmur as well as other clinical symptoms. After 4-6 weeks of birth, the resistance to PA decreases, the shunt will grow then the murmur and symptoms of heart failure will be more significant. 1.3. Diagnosis Patients with small defects are usually diagnosed when a systolic murmur is heard at the left sternum. When the resistance of the PA system increases, the murmur is weak and shorter. The Doppler cardioechography is the best diagnostic tool for VSD. Cardioechography can detect very small defects, locate very precisely because it is possible to cut many different cross-sections, this is an advantage over cardiography when limited to a few angles and using limited contrast agent. 1.4. Treatment 1.4.1. Disease natural course and prognosis Most patients with small defects of VSD grow up normally. Some studies have found that VSD self-closing rate is up to ¾ cases. The size of the defects tends to get smaller and the highest self-closing ratio in the first years. In adults with small defects, Qp / Qs <2, without PAH, the prognosis is very good. The rate of AVR and endocarditis is very low, if there is arrhythmia, it is benign. About 1/6 of VSD cases present with congestive heart failure requiring medical treatment and most likely occur within 6 months after birth. Some respond to medical treatment and do not need surgery right away, these patients often have PAH due to large defects and are at risk of developing lung disease, possibly before 2 years of age. 1.4.2. Medical treatment For medical treatment, if symptoms of heart failure occur, the medications used are digoxin, diuretic and ACE inhibitors or Angiotensin receptor inhibitors. Medical treatments only postpone surgery or follow up because the defect may close or may shrink. If the defect is small, without increasing PA pressure, there is no need to limit physical activity. Prevention of endocarditis is very important. 1.4.3. Surgical treatment of closing defects This is the classic treatment method, considered the gold standard method, especially VSD in newborns, multi-hole VSD, broad-hole VSD, receiving chamber VSD, under two arterial valves type and VSD with other lesions. The surgical mortality rate is <1%. Complications like grade 3 ABV about 1-2%, residual shunts are ≈ 5%. MI and TI may also be rare. Besides, there may be complications such as infections, neurological complications due to CPB... 1.4.4. Transcatheter closure of perimembranous VSDs using devices Since the application of VSD by devices through the catheter has been controversy about the safety, the effectiveness of this method compared to the surgical method. The development of VSD closure devices has undergone many changes to increase efficiency and reduce complications, especially pVSD closing devices. The asymmetrical double-disc device designed for pVSD (Amplatzer) with a high ABV rate in the short-medium-term, with research up to 5.7% so this device is not applied anymore. To increase efficiency and minimize accidents, recently several choices have been applied. Le VSD Coils has the advantage of reducing the ABV catastrophe, but the residual shunt and hemolysis are still high. Nguyen Lan Hieu and other authors used PDA closing devices to seal VSD and reported very good medium-term results, the success rate of about 96%. The symmetrical double-disk design is based on the Amplatzer AGA (should also be called a modified 2-disc device), the design changes to overcome the Amplatzer's disadvantages (high ABV rate). These changes are two equal concentric discs with a diameter larger than waist circumference 4mm (shrinking from eccentric disc larger than 6mm waist to concentric disc larger than 4mm waist), 3mm of the thickness (1.5 mm larger than with Amplatzer). The size name stands for the diameter of the waist (Figure 1.2). 3mmm 2mmmm 2mmm Figure 1.2: Artwork of the symmetrical double-disc design to close pVSD. In 2012, Wang et al reported experience for 8 years (2002-2011), multicenter, over 524 pVSD patients, the success rate was 95.6%, the average follow-up time was 45 months, 3 patients had severe complications (0.6%) related to valve incomplete and were under 3 years old, 104 patients had minor complications. The study concludes that pVSD closing with this device has high success and long-term follow-up and less invasive than surgery. In 2014, Yang et al reported a prospective, randomized, controlled clinical trial study of percutaneous pVSD closing or surgery. Criteria to assess the safety and effectiveness of the two above treatments. The data collected tracked over 2 years and compared the two groups and concluded that: the two methods above have very good results in the short and mid-term. Percutaneous VSD has the advantage over surgery as it causes less damage to the heart muscle, less blood transfusion, and shorter procedure and hospital stay. It costs less. In 2014, Yang et al. summarized the effectiveness and complications of pVSD closing methods. The systematic review of studies published in English-language world journals, they searched PubMed from 2003-5 / 2012, excluding small studies, studies with acquired VSD. As a result, 37 published studies included 4406 VSD patients (including 3754 pVSD patients, 419 mVSD, 47 VSD under the aortic valve, 36 VSD under two great arteries, 16 patients with multi-hole VSD, 7 cases without differential type), devices are used with many different types (Amplatzer, Coils, PDO, 2 symmetrical double discs ...). Analysis of these 37 studies concluded that closing VSD by devices is effective and safe. The limitation of this analysis is that it is difficult to analyze different types of devices and it is difficult to isolate VSD forms. In 2018, Krishna A. Mandal et al reported the long-term result of pVSD closing by symmetrical double-disk devices on 186 patients. The success rate is 96.8%, with no more shunts of 99.5% after 6 months. There were 16 (8.9%) patients with stroke right after the procedure in which 1 (0.5%) patients with ABV grade 3 and 1 (0.5%) had completely left bundle branch block, these 2 patients recovered after treatment with steroid. During the mean follow-up of 18.4 months, no major complications or BAV occurred. The study concluded that the severity of the stroke was low, no patient had late-onset ABV, the success rate was high, so this method could replace the surgical method in selected patients. CHAPTER 2: SUBJECTS AND METHODS OF THE STUDY 2.1. Criteria for selecting patients Patients diagnosed at Hanoi Heart Hospital were diagnosed with pVSD, diameter more than 2mm with left-right shunt on cardiac Doppler ultrasound, weighing ≥ 8 kg or ≥ 1 year old, with aortic valve margin ≥ 2 mm or a membrane with aneurysm, plus one of the following: recurrent pneumonia, delayed weight gain, symptoms of heart failure, dilated LV on echocardiography or Qp / Qs ≥ 1.5. 2.2. Exclusion criteria VSDs had large defects or very small, no longer had indications of closing. Moderately-severe AI, with erupted Valsalva sinus aneurysm, acquired pVSD or other surgical-required lesions. Patients with contraindications to aspirin, patients with ABV, patients, family members who do not agree to do the procedure nor participate in the study. 2.3. Time and place of research The patients were eligible for the study and had procedures done from January 2012 - December 2015, then followed up, collected and processed data.   The study was conducted at Hanoi Heart Hospital. 2.4. Type of research, devices used in research Prospective research, single center, clinical intervention, comparison before and after, no control, convenient sample selection, follow up for at least 12 months after the procedure. Selected devices are symmetrical double-disk devices with names: HEART symmetric membranous VSD Occluder của hãng Lifetech Scientific 2.5. Study process The patient was researched according to the medical records, collected clinical data, ECG, CXR, Doppler echocardiography, the results of the procedure through 8 main steps. The results monitored for complications, ECG and echocardiography within the first 24 hours and before discharge. Appointment for follow-up visits after procedures 1, 3, 12, 18 months and annually or with any unusual manifestations. Patients were re-examined clinically, performed ECG and echocardiogram. The study selected 84 patients with pVSD and performed the procedure. Successful 81 procedures, collected the data of procedures and tracked data over time, finished tracking in December 2017, then analyzed and processed the data, wrote the thesis. 2.6. Data processing Using SPSS 20.0 software to process and analyze common medical statistics. 2.7. Research ethics The study was approved by the Ethics Council and Science Council of Hanoi Heart Hospital. CHAPTER 3: RESULTS 3.1. General characteristics of the study subjects 84 patients with pVSD were selected, and 81 patients successfully had the procedure (81/84 ≈ 96.4%). The average duration of follow-up was 42.7 months (20-61 months). No patients had left the study. The average duration of hospital stay was 8.28 days. Gender, age, weight characteristics: the study included 43 males (53.1%) and 38 females (46.9%). The average age is 9.9 years (11 months - 55 years), ages <16 accounts for 81.5%. The average weight is 23.8 kg (7-67 kg). 3.2. Characteristics of VSD defect and aortic edge on echocardiography Table 3.1. Size of the defect and aortic edge on TTE n SD Min Max Size of defect (mm) 81 5,1 1,5 2,5 11,5 Aortic edge (mm) 81 5,0 2,0 1,5 11,5 Comments: Size of VSD defect is mostly medium size, the average size is 5.1 mm (2.5-11.5 mm). Aortic edge average size is 5.0 mm (1.5-11.5 mm). 3.3. Results of the VSD closing procedure Methods of analgesia: In the study, 65/81 (80%) patients underwent intravenous propofol and 16/81 (20%) patients under local anesthesia. The minimum age for anesthesia is 14 years old, the oldest age for anesthesia is 32 years old. Access: in the study, 71/81 (87.6%) patients had access to the right femoral artery and vein and 10 (12.4%) patients entered with the left femoral artery and vein, no patients use other access routes. The systolic PAP has a mean value of 27.4 mmHg (17-40). The average Qp / Qs result is 2.33 (1.7 - 3.5). The VSD defect morphology was assessed on LV images: the funnel-shaped proportion had the highest rate of 69/81 (85.19%) of patients, often accompanied by membrane aneurysm. Tubes are common after funnel-shaped, 9/81 (11.11%) patients. Window pattern is the least common with 3.7%. VSD size measured on LV chamber images: 3.86 mm on average, 3mm minimum, 8mm maximum. Aortic valve edge result: mean 3.0 mm (2.0 - 5.0 mm). Method of passing VSD from LV to RV: Directly through 0.035 wire, successfully bend the water at the tip of 58%, then by IM catheter is 28%, pigtail cut is 11%, JR catheter is 3%. The position of catching the wire (snare) to create A-V rings, in the study, from the vena cava was 66.7%, the remaining 33.3% were at the pulmonary artery. The start position of device drop: drop from the aorta up to 75.3%, also drop from the LV chamber in 24.7% of patients. Device sizes used are from 4 to 10, sizes 4, 5 and 6 accounts for 78% of the devices used. There is a size of 10 used for patients with VSD = 8 mm. The average device size is 5.63 ± 1,269 mm (4 - 10 mm). Stopping shunting immediately after releasing the device is 21%, while the low shunt is 79%, after 3 months follow up is 97,5%, 18 months is 98,8% ( small shunt after 18 month is 1,2%). AVR: No patients had any change in AVR level, 4 (4.9%) patients with mild AVR had it before the procedure. The average procedure time is 47.3 minutes (37 - 121 minutes). And the average X-ray exposing time is 22.9 minutes (11 - 54 minutes). 3.4. The difficulties and obstacles during the procedure Table 3.2. The difficulties during the procedure The difficulties during the procedure n % Through VSD have to change catheters 20 24,7 Re-catch wire (snare) 18 22,2 Change to larger size 13 16,0 Dropping the set into RV must repeat the steps 9 11,1 Cardioechography during procedure 31 38,3 Comments: 24.7% of patients had difficulty passing through the vas from the LV side where they had to change another catheter. Catching snare accounted for 22.2% while exchanging devices was greater than 16.0% of patients. The whole system dropped into RV when releasing had a rate of 11.1%. Support echocardiography during the procedure was 38.3%. 3.5. Cardiac arrhythmia events encountered during the procedure Table 3.3. Cardiac arrhythmia during the procedure Cardiac arrhythmia n % Sinus tachycardia 8 9,9 Ventricular ectopic 81 100 Short ventricular tachycardia 17 21,9 Sinus bradycardia 3 3,7 A-V Block grade 1,2 2 2,5 Others 0 0 Comments: The most common arrhythmia during work is ventricular ectopic (100%). Sinus tachycardia with 9.9%, short ventricular tachycardia met 21.9%. Sinus bradycardia met 3.7%, AVB grade 1.2 met 2/81 (2.5%). These arrhythmias recover as soon as the stimulation stops, ending the procedure. In the study, there were no patients with ABV grade 3. 3.6. Other complications and causes of failure of the procedure Respiratory complications met 6.2% of patients, manifested as increased respiratory secretion, wheezing, reduced SpO2 only managed to suction and cleanthe airways, bag-via-mask ventilation, then the patient was stable again, no case need intubation. Complications on the pathway only manifested as a small hematoma at the site of access in 8.6% of patients, only medical treatment by compressing the position of the vascular access. There are 9.9% of patients with allergic manifestations such as skin rash, but do not cause severe respiratory and circulation symptoms, only treated with corticoids and antihistamines. There are 3 patients (3.6%) fail due to anatomical factors such as large defect, defect located next to the aortic valve. 3.7. Clinical symptoms, ECG, CXR before and after the procedure Clinical: before the procedure, the symptom of delayed weight gain accounted for 25.9%, recurrent pneumonia was 33.3%, NYHA 2 was 13.6% and systolic murmur intensity ≥3 / 6 accounted for 80, 2%. Following the procedure, these symptoms gradually disappear. ECG: After the procedure, there was a significant change in LV overload signs, before procedure 28/81 (34.6%), after 18 months, only 3/81 (3.7%). Especially, no patients with ABV and other arrhythmias after 18 months. On the plain CXR before the procedure, 53.1% have a cardiac-chest index ≥ 50%. Signs of pulmonary congestion were 76.5% of patients. 3.8. Doppler echocardiography before and after the procedure Left Ventricular End Diastolic Dimension (LVEDd) before the procedure was 39.3 ± 8.0 mm, after 24 hours the procedure was 36.4 ± 8.2 mm after 1 month was 34.4 ± 7.2 mm. Comparing the mean Dd after the 24-hour and 1-month procedure saw a decrease compared to the previous procedure with statistical significance (p = 0.001, t-test). Systolic PAP measured by TI spectrum before the procedure is 31.2 ± 6.5 mmHg, after 24 hours procedure is 2.50 ± 3.5 mmHg, after 1 month is 24.6 ± 3.0 mmHg. Comparison of systolic PAP after procedure 24 hours and 1 month showed a statistically significant decrease compared to before the procedure (p <0.05, t-test). TI changes on ultrasound before and after the procedure Table 3.4. Compare TI before and after the procedure TI grade TI before procedure After 18 months n % n % 1/4 74 91,4 79 97,5 2/4 3 3,7 2 2,5 3/4 4 4,9 0 0,0 Total 81 100,0 81 100,0 Comments: The mild TI group after the procedure had 5 more patients because these patients before the procedure were moderate or high MI, in which before the procedure, there were 4 patients with high TI (3/4) with right atrial LV shunt, after the procedure no longer right atrial LV shunt. In the mild TI group, before the procedure, there were 3 patients, after the procedure, there were 2 patients (decreased 1 patient), of which 1 patient did not change the incomplete level (still 2/4) and 1 patient had an incomplete level increased from mild TI. With aortic valve, there was no change before and after the procedure with 4 (4.9%) patients with mild TI. 3.9. Compare defect size measured on US v.s cardiac catheterization Table 3.5. Compare defect size measured on US v.s cardiac catheterization Size of defect (mm) SD 95%CI p (t-test) Cardioechography 5,1 1,5 4,8 5,7 0,001 On catheterization 3,9 0,9 3,7 4,1 Comment: The mean size of VSD measured on echocardiography was significantly greater than the size measured on cardiac catheterization (p <0.05). CHAPTER 4: DISCUSSION 4.1. General characteristics of patients studied The follow-up time for our study was 42.7 ± 15.5 months (20 - 61 months). According to Nguyen Lan Hieu's research, the follow-up time is from 2 to 7 years. Lei Wang's study had a follow-up period of up to 8 years (1-96 months). The average hospitalization time is 8.28 days (3-28 days). Our study had a longer hospital stay than other studies because some patients were hospitalized with pneumonia requiring prolonged treatment. According to research by Lei Wang TB is 3.4 days. The gender distribution of other studies and we are quite similar, male / female ratio ≈ 1, epidemiological equivalent rate of VSD. The average age of our patients was 9.9 ± 11.1 years (11 months - 55 years old). According to the EUREVECO study, the age range is from 8 months to 67 years old, while the study by Lei Wang is from 2 to 12 years old, the study of Nguyen Lan Hieu is all over 1 year old. Regarding the body weight of patients, the studies all chose to weigh over 7 kg, our study was the lowest of 7.0 kg in 1-year-old patients. According to research by Nikolaus A. Haas, the lightest patient is 7.18 kg, Lei Wang's study is ≥ 9.5 kg. 4.2. History, clinical symptoms, ECG and CXR characteristics History of recurrent pneumonia: our study is 33.3%. According to Nguyen Lan Hieu, the Coils group had 19.7%, the PDA-Device group had 27.0%. According to Lei Wang, recurrent VPQ accounted for 25.9%. Slow weight gain: our study is 25.9%. According to Nguyen Lan Hieu, the Coils group is 25.4%, the PDA-Device group is 32.1%. Functional symptoms of heart failure assessment (NYHA): According to Nguyen Lan Hieu, the Coils group is 19.7%, and the PDA-Device group is 22.5% (NYHA ≥ 2). According to Lei Wang, 9.1% (8.6% NYHA2; 0.5% NYHA3; 90.9% HYHA1). Our data is 13.6% NYHA2; 76.4% NYHA1.History of endometriosis, the Lei Wang study met 0.4% (4 patients), we did not have any cases. Systolic murmur on the left sternal edge we encountered 100% of patients and the intensity of murmur ≥ 3/6 met in 80.2% of patients. In our study, ECG signs of LV overload were 34.6%, right bundle branch blocks completely were 2.5%, and the lung-heart index ≥ 50% was 53.1%. According to Lei Wang, the signs of hemodynamic changes, enlarged heart shape, increased blood flow to the lungs, and heart overload on the ECG were 73.3%. 4.3. Echocardiography characteristics Left Ventricular End Diastolic Dimension: our data are 39.3 ± 8.0 mm. Nguyen Lan Hieu: Coils group is 42.1 ± 8.7 mm, PDA-Device group is 43.3 ± 8.5 mm. Systolic PAP: our data is 30.9 ± 6.4 mmHg (20 - 50mmHg). According to Nguyen Lan Hieu, the Coils group is 34.8 ± 6.6 mmHg, the PDA-Device group is 35.9 ± 8.9 mmHg. Our PAP is lower than that of Nguyen Lan Hieu. TI: we had 4 patients with severe TI with shunt LV-RA and 3 patients with moderate TI, the rest were mild TI (91.36%). In the report of Gunter Kerst in 2015 in Germany in 4 patients with LV-RA shunt, these patients were VSD closing by 2nd generation arterial closure device (PDO II) recorded no LV-RA shunt after the procedure. 4.4. Characteristics of VSD on echocardiography Our results have a size of defect of 5.1 ± 1.5 mm (2.5 - 11.5 mm), a diaphragm aneurysm of 45%, aortic valve edge of size 5.0 ± 2.0 mm (1.5 - 11.5). VSD characteristics of our study are quite similar to those of other authors. According to Nguyen Lan Hieu, the VSD of the DO group is 4.4 ± 1.2 mm, the Coils group is 4.1 ± 1.5 mm. The DO group aneurysm is 48.3%, the Coils group is 66.2%, the aortic edge of the DO group is 3.5 ± 1.4 mm, the Coils group is 3.7 ± 2.9 mm. According to Lei Wang, VSD is 4.4 mm (2.3 - 10.3 mm), the aorta edge is 3.2 mm (1.0 - 18.3 mm). 4.5. Characteristics of VSD closing procedure In our study, we selected the femoral artery and vein for all cases. 20% local anesthesia and 80% IV anesthesia. According to EUREVECO's study of 111 patients, 15.3% of the way through the carotid vein, the rest has performed by the artery and femoral vein, this is the basic and convenient access. For general anesthesia and analgesia, 49.5% had mild sedation and 50.5% used general anesthesia. Systolic PAP is 27.4 ± 4.7 mmHg (17-40 mmHg), Qp / Qs is 2.33 ± 0.43 (1.7-3.5). Our results are similar to those of other authors. According to Nguyen Lan Hieu, the Qp / Qs of the DO group is 2.2 ± 0.7, the Coils group is 2.1 ± 0.7. According to Lei Wang, the average value of systolic PAP is 25.6 mmHg (18-55 mmHg), Qp / Qs has an average value of 2.5 (1.7-6.8). VSD characteristics on LV chamber image: Our result, the size of defects were 3.86 ± 0.93 mm (3.0-8.0). The morphology is the funnel-shaped and diaphragm-shaped aneurysm of 85.19% followed by the 11.11% tubular and 3.7% window-shaped. Aortic edge is 3.0 ± 0.7 mm (2.0 - 5.0), our characteristics are similar to other authors. According to Nguyen Lan Hieu, the size of defect of DO group is 4.7 ± 2.0 mm, Coils group is 4.4 ± 1.7 mm, DO's aortic valve edge is 3.3 ± 1.1 mm, group Coils are 3.1 ± 0.9 mm. According to Lei Wang, the average size of the defect is 4.6 mm (1.9-21.6), the tubular form accounts for 23.2%, the window shape accounts for 2.9%, the diaphragm aneurysm accounts for 9.2%, funnel-shaped for 64.7%. Tools: our results are 5.6 ± 1.3 mm (4-10), the numbers 5 and 6 account for 58%, so our device size is smaller than our research Lei Wang (TB is 6.5 mm, the smallest is 4 mm, the largest is 18 mm). In our study through VSD with a wire of 58% success, then an IM catheter of 28%, with a pigtail cut 11% and finally a 3% JR. The direct method of wire is more convenient, less arrhythmic when doing the procedure than using the catheter. The position of catching the wire (snare) in the superior or inferior vena cava accounts for 66.7%, the rest is at the pulmonary artery. The rate at which the device drop usually starts from the aorta is 75.3%, the remainder from the LV. According to the EUREVECO study, passing through the common hole is the JR catheter then caught the snare in the pulmonary artery, and the starting point for releasing the device is from the aorta. 4.6. Characteristics of success, causes of failure Our success rate is 96.4%, according to Nguyen Lan Hieu of the Coils group, which has a higher success rate than the DO group (DO: 95.6%; Coils: 97.2%). Cause of device failure caused by AI: according to Lei Wang's research is 2.3%, according to EUREVECO's research, 1.8%, and Nguyen Lan Hieu's research in DO group is 0,3%, our results showed 1 patient (1.2%) had AI so he had to stop the procedure. Shunt residue group: according to EUREVECO's research, 1.8%, while Nguyen Lan Hieu's research in DO group is 0.6%, Coils group is 1.4%, their results I met 1 patient (1.2%) with large residual shunt who had to stop the procedure. The fourth group was for TI, according to Lei Wang's stu