Combination therapy of liothyronine and levothyroxine for hypothyroidism-induced dilated cardiomyopathy

Thyroid hormone plays a vital role in regulating human metabolism. They affect the functions of major organs, such as the brain, liver, skeletal muscle, and heart. Hypothyroidism can lead to dilated cardiomyopathy and decreased heart function. In this report, we describe a case of a teenage boy who developed dilated cardiomyopathy due to hypothyroidism and was considered to undergo heart transplantation. Levothyroxine monotherapy was initiated but produced no improvement. Thereafter, a combination therapy of liothyronine and levothyroxine was administered, and heart function was gradually restored; he recovered completely after 6 months. Cardiac myocytes respond more specifically to liothyronine than to levothyroxine. Therefore, we suggest that liothyronine and levothyroxine combination therapy should be considered rather than levothyroxine monotherapy for hypothyroidism accompanied by heart disease.

The First Pediatric Heart Transplantation Bridged by a Durable Left Ventricular Assist Device in Korea

Treatment options for children with end-stage heart failure are limited. We report the first case of a successful pediatric heart transplantation bridged with a durable left ventricular assist device in Korea. A 10-month-old female infant with dilated cardiomyopathy and left ventricular non-compaction was listed for heart transplantation. During the waiting period, the patient’s status deteriorated. Therefore, we decided to provide support with a durable left ventricular assist device as a bridge to transplantation. The patient was successfully bridged to heart transplantation with effective support and without any major adverse events.

Characterization of Flow Efficiency, Pulsatility, and Respiratory Variability in Different Types of Fontan Circuits Using Quantitative Parameters

PURPOSE: Details on the hemodynamic differences among Fontan operations remain unclear according to respiratory and cardiac cycles. This study was undertaken to investigate hemodynamic characteristics in different types of Fontan circulation by quantification of blood flow with the combined influence of cardiac and respiratory cycles. MATERIALS AND METHODS: Thirty-five patients [10 atriopulmonary connections (APC), 13 lateral tunnels (LT), and 12 extracardiac conduits (ECC)] were evaluated, and parameters were measured in the superior vena cava, inferior vena cava (IVC), hepatic vein (HV), baffles, conduits, and left and right pulmonary artery. Pulsatility index (PIx), respiratory variability index (RVI), net antegrade flow integral (NAFI), and inspiratory/expiratory blood flow (IQ/EQ) were measured by intravascular Doppler echocardiography. RESULTS: The PIx between APC and total cavopulmonary connection (TCPC; LT and ECC) showed significant differences at all interrogation points regardless of respiratory cycles. The PIxs of HVs and IVCs in APC significantly increased, compared with that in LT and ECC, and the RVI between APC and TCPC showed significant differences at all interrogation points (p < 0.05). The NAFI and IQ/EQ between APC and TCPC showed significant differences at some interrogation points (p < 0.05). CONCLUSION: Patients with different types of Fontan circulation show different hemodynamic characteristics in various areas of the Fontan tract, which may lead to different risks causing long-term complications. We believe the novel parameters developed in this study may be used to determine flow characteristics and may serve as a clinical basis of management in patients after Fontan operations.

Procedural, Early and Long-term Outcomes after Percutaneous Closure of Atrial Septal Defect: Comparison between Large and Very Large Atrial Septal Defect Groups

BACKGROUND: This study aimed to compare procedural, early and long-term outcome of device closure of atrial septal defect (ASD) between large ASD patients and very large ASD patients. METHODS: We carried a retrospective study of adult large ASD (defined as ≥25 mm) treated by percutaneous closure using Amplatzer septal occluder during 12-year period (May 2003–February 2015) at a single tertiary center. A total of 269 patients were divided into 2 groups, according to the pre-procedural maximal ASD diameter; 25 mm≤ASD<35mm, group 1 (n=216) and 35 mm≤ASD, group 2 (n=53). We compared procedural parameters, early complications and long-term follow-up results between 2 groups. RESULTS: The need of modified implantation techniques (MITs) was higher group 2 (23.6% vs. 37.7%, p=0.034). Procedural success rate was considerably high in both groups (99.1% in group 1 vs. 100% in group 2, p=0.620). Major complications were occurred in 4 (1.5%) patients (1.4% vs. 1.9%, p=0.804). Minor complication rate was not different between 2 groups. During long-term follow-up (47.2±32.0 months, range, 6.0–135.5), there was one major complication (0.4%) of stroke. Most common long-term minor event was migraine headache (3.9%) followed by arrhythmias (1.9%) without statistical difference between 2 groups. CONCLUSIONS: Although MIT was more frequently required in very large ASD groups, the procedural, early and long-term outcomes after percutaneous ASD closure were similar in both groups. This suggested that percutaneous ASD closure for very large ASD could be considered a good treatment option.

Early to Mid-Term Follow-Up Outcomes of Percutaneous Closure of Atrial Septal Defects Using Recent Generation Devices: a Single-Center Experience

BACKGROUND AND OBJECTIVES: This study aimed to describe our early to mid-term experience with transcatheter atrial septal defect (ASD) closure using the Occlutech Figulla® Flex II device (FSO), Gore® Cardioform septal occluder (GSO), and Amplatzer® septal occluder (ASO) after they were first approved in Korea in 2014, and to compare the three aforementioned kinds of ASD closure devices. METHODS: Between September 2014 and August 2016, 267 patients underwent transcatheter ASD closure in our institution. Baseline characteristics, hemodynamic features, comorbidities, and procedural success and complication rates were analyzed retrospectively. The unpaired Student t-test or variance analysis was used in the statistical analysis. RESULTS: The FSO was most commonly used (n=152, 56.9%), followed by the ASO (n=98, 36.7%) and GSO (n=17, 6.4%). Baseline characteristics and hemodynamic features were similar between the devices, except that the defect size and pulmonary flow-to-systemic flow ratio were lower in the GSO group than in the other groups. Overall, the procedural success rate remained at 100%, and major complication rate was < 1%. No late complication occurred during the follow-up. CONCLUSIONS: The FSO and GSO are feasible, safe options for use in transcatheter ASD closure, and they are comparable to the ASO.

Procedural, Early and Long-term Outcomes after Percutaneous Closure of Atrial Septal Defect: Comparison between Large and Very Large Atrial Septal Defect Groups

BACKGROUND@#This study aimed to compare procedural, early and long-term outcome of device closure of atrial septal defect (ASD) between large ASD patients and very large ASD patients.@*METHODS@#We carried a retrospective study of adult large ASD (defined as ≥25 mm) treated by percutaneous closure using Amplatzer septal occluder during 12-year period (May 2003–February 2015) at a single tertiary center. A total of 269 patients were divided into 2 groups, according to the pre-procedural maximal ASD diameter; 25 mm≤ASD<35mm, group 1 (n=216) and 35 mm≤ASD, group 2 (n=53). We compared procedural parameters, early complications and long-term follow-up results between 2 groups.@*RESULTS@#The need of modified implantation techniques (MITs) was higher group 2 (23.6% vs. 37.7%, p=0.034). Procedural success rate was considerably high in both groups (99.1% in group 1 vs. 100% in group 2, p=0.620). Major complications were occurred in 4 (1.5%) patients (1.4% vs. 1.9%, p=0.804). Minor complication rate was not different between 2 groups. During long-term follow-up (47.2±32.0 months, range, 6.0–135.5), there was one major complication (0.4%) of stroke. Most common long-term minor event was migraine headache (3.9%) followed by arrhythmias (1.9%) without statistical difference between 2 groups.@*CONCLUSIONS@#Although MIT was more frequently required in very large ASD groups, the procedural, early and long-term outcomes after percutaneous ASD closure were similar in both groups. This suggested that percutaneous ASD closure for very large ASD could be considered a good treatment option.

Early to Mid-Term Follow-Up Outcomes of Percutaneous Closure of Atrial Septal Defects Using Recent Generation Devices: a Single-Center Experience

BACKGROUND AND OBJECTIVES@#This study aimed to describe our early to mid-term experience with transcatheter atrial septal defect (ASD) closure using the Occlutech Figulla® Flex II device (FSO), Gore® Cardioform septal occluder (GSO), and Amplatzer® septal occluder (ASO) after they were first approved in Korea in 2014, and to compare the three aforementioned kinds of ASD closure devices.@*METHODS@#Between September 2014 and August 2016, 267 patients underwent transcatheter ASD closure in our institution. Baseline characteristics, hemodynamic features, comorbidities, and procedural success and complication rates were analyzed retrospectively. The unpaired Student t-test or variance analysis was used in the statistical analysis.@*RESULTS@#The FSO was most commonly used (n=152, 56.9%), followed by the ASO (n=98, 36.7%) and GSO (n=17, 6.4%). Baseline characteristics and hemodynamic features were similar between the devices, except that the defect size and pulmonary flow-to-systemic flow ratio were lower in the GSO group than in the other groups. Overall, the procedural success rate remained at 100%, and major complication rate was < 1%. No late complication occurred during the follow-up.@*CONCLUSIONS@#The FSO and GSO are feasible, safe options for use in transcatheter ASD closure, and they are comparable to the ASO.

Changes in Strain Pattern and Exercise Capacity after Transcatheter Closure of Atrial Septal Defects

BACKGROUND AND OBJECTIVES: Assessment of left ventricle (LV) function by using strain and strain rate is popular in the clinical setting. However, the use of these echocardiographic tools in assessing right ventricle (RV) failure, and the manner in which they both reflect the functional capacity of the patient, remains poorly understood. This study aimed to investigate the change in exercise capacity and strain between before and (1 month) after the transcatheter closure of atrial septal defects (ASDs). SUBJECTS AND METHODS: Thirty patients who underwent transcatheter closure of ASD between May 2014 and June 2015 at the Division of Pediatric Cardiology, Severance Cardiovascular Hospital, were enrolled. We compared and analyzed the results of the following examinations, before and (1 month) after the procedure: echocardiography, cardiopulmonary exercise test (CPET), and N-terminal pro-brain natriuretic peptide level. RESULTS: There were no mortalities, and the male-to-female ratio was 1:2. The mean defect size was 22.3±4.9 mm; the mean Qp/Qs ratio, 2.1±0.5; and the mean device size, 22.3±4.9 mm. Changes in global RV longitudinal (GRVL) strain and LV torsion were measured echocardiographically. Exercise capacity improved from 7.7±1.2 to 8.7±1.8 metabolic equivalents (p=0.001). These findings correlated to the change in GRVL strain (p=0.03). CONCLUSION: The average exercise capacity increased after device closure of ASD. The change in strain was evident on echocardiography, especially for GRVL strain and LV torsion. Further studies comparing CPET and strain in various patients may show increased exercise capacity in patients with improved RV function.

Retrospective Multicenter Study of Respiratory Syncytial Virus Prophylaxis in Korean Children with Congenital Heart Diseases

BACKGROUND AND OBJECTIVES: We conducted a review of current data on respiratory syncytial virus (RSV) prophylaxis with palivizumab, in Korean children with congenital heart diseases (CHD). In 2009, the Korean guideline for RSV prophylaxis had established up to five shots monthly per RSV season, only for children <1 year of age with hemodynamic significance CHD (HS-CHD). SUBJECTS AND METHODS: During the RSV seasons in 2009-2015, we performed a retrospective review of data for 466 infants with CHD, examined at six centers in Korea. RESULTS: Infants received an average of 3.7±1.9 (range, 1-10) injections during the RSV season. Fifty-seven HS-CHD patients (12.2%) were hospitalized with breakthrough RSV bronchiolitis, with a recurrence in three patients, one year after the initial check-up. Among patients with simple CHD, only five (1.1%) patients received one additional dose postoperatively, as per the limitations set by the Korean guideline. Among the 30 deaths (6.4%), five (1.1%) were attributed to RSV infection; three to simple CHD, one to Tetralogy of Fallot, and one to hypertrophic cardiomyopathy (HCM). Of the three HCM patients that exceeded guidelines for RSV prophylaxis, two (66.6%) were hospitalized, and one died of RSV infection (33.3%). CONCLUSION: In accordance to the Korean guideline, minimal injections of palivizumab were administered to patients having HS-CHD

Transcatheter Treatment of Atrial Septal Defect Presenting with Platypnea-Orthodeoxia Syndrome

A 29-year-old woman was referred to our institute for symptomatic hypoxemia. Her dyspnea was aggravated while sitting or standing and relieved while in supine position. She did not have any pulmonary disease. Transthoracic echocardiography and heart computed tomography revealed an underestimated small atrial septal defect (ASD) with a left-to-right shunt. A cardiac catheterization was performed to evaluate pulmonary hypertension. It revealed a normal pulmonary artery pressure and a large ASD with bidirectional shunt during Valsalva maneuver by intracardiac echocardiogram. Her arterial oxygen saturation decreased from 93% while supine to 79% while at a 15degrees sitting position. Thus, the patient was diagnosed with platypnea-orthodeoxia syndrome. The ASD was successfully closed with Amplatzer(R) (St. Jude Medical) septal occluder and both platypnea and orthodeoxia were resolved immediately after the procedure.

A case of thyrotoxic periodic paralysis as initial manifestation of Graves' disease in a 16-year-old Korean adolescent

Thyrotoxic periodic paralysis (TPP) is a rare complication of hyperthyroidism, with recurrent muscle paralysis and hypokalemia that are caused by an intracellular shift of potassium. TPP is relatively common in Asian males, but is extremely rare in children and adolescents, even for those of Asian descent. We describe a 16-year-old Korean adolescent presenting with a two-week history of episodic leg weakness in the morning. He showed sinus tachycardia, lower leg weakness, and hypokalemia. Thyroid function test showed hyperthyroidism, and thyroid ultrasonography revealed a diffuse enlarged thyroid with increased vascularity, consistent with Graves' disease. He was treated with beta-adrenergic blocker and antithyroid drugs. He has been symptom free for one year, as his hyperthyroidism has been controlled well with antithyroid drugs. TPP should be considered in children and adolescents with acute paralysis of the lower extremities and hypokalemia.

Radiation or Chemotherapy rather than Observation may be a Better Modality after Subtotal Resection for Pilocytic Astrocytoma in Children / 임상소아혈액종양

BACKGROUND: Pilocytic astrocytoma (PA) is a low-grade glioma that occurs primarily in children and young adults. The optimal postoperative treatment modality after subtotal resection (STR) of PAs remains to be elucidated. The aim of this study was to compare the efficacies of different post-STR treatment modalities and to examine the risk factors for the progression of PAs. METHODS: We reviewed the medical records of 91 pediatric PA patients in a single institute during a 30-year period. Kaplan-Meier analysis was used to assess overall survival (OS) and progression-free survival (PFS), and Cox proportional hazard models were used to calculate hazard ratios. RESULTS: The median age of 91 patients was 8.9 years (range, 0.3-17.9). GTR was perfomed, whenever possible. Patients who underwent STR afterwards received either radiotherapy, chemotherapy, or were observed without further treatment, according to clinician preference. In total group, 10-year OS was 97.4% and 10-year PFS was 57.2%. In GTR group (N=33), 10-year OS and PFS was 100%. In STR group (N=49), 10-year OS was 97.7%, while 10-year PFS was 38.6%. STR group underwent following postoperative (PO) modalities; observation (PO-Obs, N=32), radiotherapy (PO-RT, N=10), chemotherapy (PO-CTx, N=7). The 10-year PFS rate was higher in patients who received postoperative treatment (either PO-RT or PO-CTx) than in patients who received PO-Obs (62.5% vs 27.0%, P=0.039). In multivariate analysis for STR group, PO-CTx (Hazard ratio (HR)=0.20, P=0.035) and PO-RTx (HR=0.13, P=0.008) were superior to observation, respectively. CONCLUSION: Radiation and chemotherapy are better post-STR treatment modalities than observation for pediatric PA patients.

Radiation or Chemotherapy rather than Observation may be a Better Modality after Subtotal Resection for Pilocytic Astrocytoma in Children / 임상소아혈액종양

BACKGROUND: Pilocytic astrocytoma (PA) is a low-grade glioma that occurs primarily in children and young adults. The optimal postoperative treatment modality after subtotal resection (STR) of PAs remains to be elucidated. The aim of this study was to compare the efficacies of different post-STR treatment modalities and to examine the risk factors for the progression of PAs.METHODS: We reviewed the medical records of 91 pediatric PA patients in a single institute during a 30-year period. Kaplan-Meier analysis was used to assess overall survival (OS) and progression-free survival (PFS), and Cox proportional hazard models were used to calculate hazard ratios.RESULTS: The median age of 91 patients was 8.9 years (range, 0.3-17.9). GTR was perfomed, whenever possible. Patients who underwent STR afterwards received either radiotherapy, chemotherapy, or were observed without further treatment, according to clinician preference. In total group, 10-year OS was 97.4% and 10-year PFS was 57.2%. In GTR group (N=33), 10-year OS and PFS was 100%. In STR group (N=49), 10-year OS was 97.7%, while 10-year PFS was 38.6%. STR group underwent following postoperative (PO) modalities; observation (PO-Obs, N=32), radiotherapy (PO-RT, N=10), chemotherapy (PO-CTx, N=7). The 10-year PFS rate was higher in patients who received postoperative treatment (either PO-RT or PO-CTx) than in patients who received PO-Obs (62.5% vs 27.0%, P=0.039). In multivariate analysis for STR group, PO-CTx (Hazard ratio (HR)=0.20, P=0.035) and PO-RTx (HR=0.13, P=0.008) were superior to observation, respectively.CONCLUSION: Radiation and chemotherapy are better post-STR treatment modalities than observation for pediatric PA patients.