Evaluation of craniofacial morphology in short-statured children: growth hormone deficiency versus idiopathic short stature / 영남의대학술지

Background@#Short stature is defined as a height below the 3rd percentile or more than two standard deviations below the mean for a given age, sex, and population. There have been inconsistent results regarding craniofacial morphology in short-statured children. This study aimed to analyze the differences between short-statured children with growth hormone deficiency, idiopathic short-statured children, and normal children. @*Methods@#Thirty-one short-statured children with growth hormone deficiency, 32 idiopathic short-statured children, and 32 healthy children were enrolled in this study. The measurements of their craniofacial structures from lateral cephalograms were evaluated. @*Results@#There were statistically significant differences among the three groups seven variables (anterior cranial base length, posterior cranial base length, total cranial base length, upper posterior facial height, posterior total facial height, mandibular ramus length, and overall mandibular length) in the linear measurement and five variables (saddle angle, gonial angle, mandibular plane angle, position of mandible, and maxilla versus mandible) in the angular measurement. @*Conclusion@#Compared to the control group, many linear and angular measurements of the craniofacial structures were significantly different in the two short-statured groups (p<0.05). Treatment plans by orthodontists should include these craniofacial structure characteristics.

The Performance of the Current Risk Prediction Scoring Systems in Patients Undergoing Anaortic Off-pump Coronary Artery Bypass Grafting

Background@#This study aimed to evaluate the performance of the Society of Thoracic Surgeons (STS) risk model and European System for Cardiac Operative Risk Evaluation (EuroSCORE) II for patients undergoing anaortic off-pump coronary artery bypass grafting (OPCAB). @*Methods@#From January 2010 to June 2017, 1,048 patients (isolated anaortic OPCAB: 1,043, on-pump conversion:5) undergoing isolated anaortic OPCAB were enrolled. The STS risk score and EuroSCORE II were calculated with dedicated online software. Calibration of the models were performed by the risk-adjusted event ratio that was defined as observed events divided by expected events (O/E ratio) and Hosmer-Lemeshow test. The discrimination powers were evaluated by the area under the receiver operating characteristic curve (AUC). @*Results@#Operative mortality occurred in 10 patients (0.95%). The predicted mortality rates by the EuroSCORE II and STS risk model were 2.58 ± 4.15% and 1.72 ± 2.92%, respectively. The O/E ratio of the EuroSCORE II was 0.370 with significant overprediction of operative mortality (confidence interval [CI], 0.157–0.652; P = 0.003). The STS score also overpredicted the operative mortality (O/E ratio, 0.556) with marginal significance (CI, 0.266–1.023; P = 0.052). Permanent stroke occurred in 6 patients (0.53%). The predicted permanent stroke occurrence rate was 1.73 ± 1.48%. The O/E ratio was 0.332 with significant overprediction of permanent stroke (CI, 0.121–0.722; P = 0.011). Regarding discrimination power for the STS risk model, the operative mortality was excellent (AUC, 0.876) and permanent stroke was acceptable (AUC, 0.740). The EuroSCORE II showed good discrimination power (AUC, 0.784). There was a significant difference in discrimination power for mortality between STS and EuroSCORE II risk models (P = 0.007). @*Conclusion@#Preexisting risk predicting scoring systems, STS risk model and EuroSCORE II, overpredict the risk of mortality and stroke rate for anaortic OPCAB. These findings suggest the possibility that anaortic OPCAB can lower the operative mortality and occurrence of postoperative stroke than conventional coronary artery bypass grafting.

The Performance of the Current Risk Prediction Scoring Systems in Patients Undergoing Anaortic Off-pump Coronary Artery Bypass Grafting

Background@#This study aimed to evaluate the performance of the Society of Thoracic Surgeons (STS) risk model and European System for Cardiac Operative Risk Evaluation (EuroSCORE) II for patients undergoing anaortic off-pump coronary artery bypass grafting (OPCAB). @*Methods@#From January 2010 to June 2017, 1,048 patients (isolated anaortic OPCAB: 1,043, on-pump conversion:5) undergoing isolated anaortic OPCAB were enrolled. The STS risk score and EuroSCORE II were calculated with dedicated online software. Calibration of the models were performed by the risk-adjusted event ratio that was defined as observed events divided by expected events (O/E ratio) and Hosmer-Lemeshow test. The discrimination powers were evaluated by the area under the receiver operating characteristic curve (AUC). @*Results@#Operative mortality occurred in 10 patients (0.95%). The predicted mortality rates by the EuroSCORE II and STS risk model were 2.58 ± 4.15% and 1.72 ± 2.92%, respectively. The O/E ratio of the EuroSCORE II was 0.370 with significant overprediction of operative mortality (confidence interval [CI], 0.157–0.652; P = 0.003). The STS score also overpredicted the operative mortality (O/E ratio, 0.556) with marginal significance (CI, 0.266–1.023; P = 0.052). Permanent stroke occurred in 6 patients (0.53%). The predicted permanent stroke occurrence rate was 1.73 ± 1.48%. The O/E ratio was 0.332 with significant overprediction of permanent stroke (CI, 0.121–0.722; P = 0.011). Regarding discrimination power for the STS risk model, the operative mortality was excellent (AUC, 0.876) and permanent stroke was acceptable (AUC, 0.740). The EuroSCORE II showed good discrimination power (AUC, 0.784). There was a significant difference in discrimination power for mortality between STS and EuroSCORE II risk models (P = 0.007). @*Conclusion@#Preexisting risk predicting scoring systems, STS risk model and EuroSCORE II, overpredict the risk of mortality and stroke rate for anaortic OPCAB. These findings suggest the possibility that anaortic OPCAB can lower the operative mortality and occurrence of postoperative stroke than conventional coronary artery bypass grafting.

Hemodynamic Performance of Pericardial Bioprostheses in the Aortic Position

Background@#This study was conducted to evaluate the hemodynamic performance and the incidence of prosthesis-patient mismatch (PPM) after aortic valve replacement (AVR) using bovine pericardial valves (Carpentier-Edwards Perimount Magana and Magna Ease). @*Methods@#In total, 216 patients (mean age, 70.0±10.5 years) who underwent AVR using stented bovine pericardial valves and had follow-up echocardiography between 3 months and 2 years (mean, 12.0±6.6 months) after surgery were enrolled. The implanted valve sizes were 19, 21, 23, and 25 mm in 32, 56, 99, and 29 patients, respectively. @*Results@#On follow-up echocardiography, the mean transvalvular pressure gradients for the 19-mm, 21-mm, 23-mm, and 25-mm valves were 13.3±4.4, 12.6±4.2, 10.5±3.9, and 10.2± 3.7 mm Hg, respectively. The effective orifice area (EOA) was 1.25±0.26, 1.54±0.31, 1.81±0.41, and 1.87±0.33 ㎠ , respectively. These values were smaller than those suggested by the manufacturer for the corresponding sizes. No patients had PPM, when based on the reference EOA. However, moderate (EOA index ≤0.85㎠ /㎡ ) and severe (EOA index ≤0.65 ㎠ /㎡ ) PPM was present in 56 patients (11.8%) and 9 patients (1.9%), respectively, when using the measured values. @*Conclusion@#Carpentier-Edwards Perimount Magna and Magna Ease bovine pericardial valves showed satisfactory hemodynamic performance with low rates of PPM, although the reference EOA could overestimate the true EOA for individual patients.

Early Surgery versus Watchful Waiting in Patients with Moderate Aortic Stenosis and Left Ventricular Systolic Dysfunction

Background and Objectives@#Severe aortic stenosis (AS) with left ventricular systolic dysfunction (LVSD) is a class I indication for aortic valve replacement (AVR) but this recommendation is not well established in those at the stage of moderate AS. We investigate the clinical impact of AVR among patients with moderate AS and LVSD. @*Methods@#From 2001 to 2017, we consecutively identified patients with moderate AS and LVSD, defined as aortic valve area 1.0–1.5 cm2 and left ventricular ejection fraction <50%. The primary outcome was all-cause death. The outcomes were compared between those who underwent early surgical AVR (within 2 years of index echocardiography) at the stage of moderate AS versus those who were followed medically without AVR at the outpatient clinic. @*Results@#Among 255 patients (70.1±11.3 years, male 62%), 37 patients received early AVR. The early AVR group was younger than the medical observation group (63.1±7.9 vs. 71.3±11.4) with a lower prevalence of hypertension and chronic kidney disease. During a median 1.8-year follow up, 121 patients (47.5%) died, and the early AVR group showed a significantly lower all-cause death rate than the medical observation group (5.03PY vs. 18.80PY, p<0.001). After multivariable Cox-proportional hazard regression adjusting for age, sex, comorbidities, and laboratory data, early AVR at the stage of moderate AS significantly reduced the risk of death (hazard ratio, 0.43; 95% confidence interval 0.20–0.91; p=0.028). @*Conclusions@#In patients with moderate AS and LVSD, AVR reduces the risk of all-cause death. A prospective randomized trial is warranted to confirm our findings.

The Effects of Preoperative Aspirin on Coronary Artery Bypass Surgery: a Systematic Meta-Analysis

BACKGROUND AND OBJECTIVES@#Aspirin plays an important role in the maintenance of graft patency and the prevention of thrombotic event after coronary artery bypass graft surgery (CABG). However, the use of preoperative aspirin is still under debate due to the risk of bleeding.@*METHODS@#From PubMed, EMBASE, and Cochrane Central Register of Controlled Trials, data were extracted by 2 independent reviewers. Meta-analysis using random effect model was performed.@*RESULTS@#We performed a systemic meta-analysis of 17 studies (12 randomized controlled studies and 5 non-randomized registries) which compared clinical outcomes of 9,101 patients who underwent CABG with or without preoperative aspirin administration. Preoperative aspirin increased chest tube drainage (weighted mean difference 177.4 mL, 95% confidence interval [CI], 41.3–313.4; p=0.011). However, the risk of re-operation for bleeding was not different between the preoperative aspirin group and the control group (3.2% vs. 2.4%; odds ratio [OR], 1.23; 95% CI, 0.94–1.60; p=0.102). There was no difference in the rates of all-cause mortality (1.6% vs. 1.5%; OR, 0.98; 95% CI, 0.64–1.49; p=0.920) and myocardial infarction (MI) (8.7% vs. 10.4%; OR, 0.83; 95% CI, 0.66–1.04; p=0.102) between patients with and without preoperative aspirin administration.@*CONCLUSIONS@#Although aspirin increased the amount of chest tube drainage, it was not associated with increased risk of re-operation for bleeding. In addition, the risks of early postoperative all-cause mortality and MI were not reduced by using preoperative aspirin.

Frailty Index is Associated with Adverse Outcomes after Aortic Valve Replacement in Elderly Patients

BACKGROUND: This study was conducted to evaluate the prognostic value of the frailty index based on routine laboratory data (FI-L) in elderly patients who underwent surgical aortic valve replacement (SAVR). METHODS: A total of 154 elderly patients (≥ 75 years) (78.7 ± 3.6 years; men:women = 78:76) who underwent aortic valve replacement with stented bioprosthesis between 2001 and 2018 were enrolled. The FI-L was calculated as the proportion of abnormal results out of 32 items based on laboratory tests, pulse rate and blood pressure. The primary outcome was all-cause mortality. Secondary outcomes included operative mortality and aortic valve-related events (AVREs) during follow-up. The predictive values of FI-L for the early and late outcomes were evaluated using logistic regression and Cox proportional hazards models, respectively. The median follow-up duration was 40 months (interquartile, 15–74). RESULTS: The operative mortality rate was 3.9% (n = 6). Late death occurred in 29 patients. The overall survival (OS) rates at 5, 10, and 15 years were 83.3%, 59.0%, and 41.6%, respectively. The AVREs occurred in 28 patients and the freedom rates from AVREs at 5, 10, and 15 years were 79.4%, 72.7%, and 52.9%, respectively. Multivariable analyses demonstrated that FI-L was a significant factor for OS (hazard ratio, 1.075; 95% confidence interval, 1.040–1.111). A minimal P value approach showed that a FI-L of 25% was the best cutoff value to predict OS after SAVR. CONCLUSION: The FI-L is significantly associated with early and long-term outcomes after SAVR in elderly patients. Frailty rather than a patient's age should be considered in the decision-making process for SAVR in elderly patients.

Comparison of the Plasma Metabolome Profiles Between the Internal Thoracic Artery and Ascending Aorta in Patients Undergoing Coronary Artery Bypass Graft Surgery Using Gas Chromatography Time-of-Flight Mass Spectrometry

BACKGROUND: The left internal thoracic artery (LITA) has been used as the first conduit of choice in coronary artery bypass grafting (CABG) because of excellent long-term patency and outcomes. However, no studies have examined substances other than nitric oxide that could be beneficial for the bypass conduit, native coronary artery or ischemic myocardium. This study was conducted to evaluate differences in metabolic profiles between the LITA and ascending aorta using gas chromatography-time of flight-mass spectrometry (GC-TOF-MS). METHODS: Twenty patients who underwent CABG using the LITA were prospectively enrolled. Plasma samples were collected simultaneously from the LITA and ascending aorta. GC-TOF-MS based untargeted metabolomic analyses were performed and a 2-step volcano plot analysis was used to identify distinguishable markers from two plasma metabolome profiles. Semi-quantitative and quantitative analyses were performed using GC-TOF-MS and enzyme-linked immunosorbent assay, respectively, after selecting target metabolites based on the metabolite set enrichment analysis. RESULTS: Initial volcano plot analysis demonstrated 5 possible markers among 851 peaks detected. The final analysis demonstrated that the L-cysteine peak was significantly higher in the LITA than in the ascending aorta (fold change = 1.86). The concentrations of intermediate metabolites such as L-cysteine, L-methionine and L-cystine in the ‘cysteine and methionine metabolism pathway' were significantly higher in the LITA than in the ascending aorta (2.0-, 1.4- and 1.2-fold, respectively). Quantitative analysis showed that the concentration of hydrogen sulfide (H2S) was significantly higher in the LITA. CONCLUSION: The plasma metabolome profiles of the LITA and ascending aorta were different, particularly higher plasma concentrations of L-cysteine and H2S in the LITA.

The Effects of Preoperative Aspirin on Coronary Artery Bypass Surgery: a Systematic Meta-Analysis

BACKGROUND AND OBJECTIVES: Aspirin plays an important role in the maintenance of graft patency and the prevention of thrombotic event after coronary artery bypass graft surgery (CABG). However, the use of preoperative aspirin is still under debate due to the risk of bleeding. METHODS: From PubMed, EMBASE, and Cochrane Central Register of Controlled Trials, data were extracted by 2 independent reviewers. Meta-analysis using random effect model was performed. RESULTS: We performed a systemic meta-analysis of 17 studies (12 randomized controlled studies and 5 non-randomized registries) which compared clinical outcomes of 9,101 patients who underwent CABG with or without preoperative aspirin administration. Preoperative aspirin increased chest tube drainage (weighted mean difference 177.4 mL, 95% confidence interval [CI], 41.3–313.4; p=0.011). However, the risk of re-operation for bleeding was not different between the preoperative aspirin group and the control group (3.2% vs. 2.4%; odds ratio [OR], 1.23; 95% CI, 0.94–1.60; p=0.102). There was no difference in the rates of all-cause mortality (1.6% vs. 1.5%; OR, 0.98; 95% CI, 0.64–1.49; p=0.920) and myocardial infarction (MI) (8.7% vs. 10.4%; OR, 0.83; 95% CI, 0.66–1.04; p=0.102) between patients with and without preoperative aspirin administration. CONCLUSIONS: Although aspirin increased the amount of chest tube drainage, it was not associated with increased risk of re-operation for bleeding. In addition, the risks of early postoperative all-cause mortality and MI were not reduced by using preoperative aspirin.

Surgical Treatment of Degenerative Mitral Valve Regurgitation in the Elderly: Comparison of Early and Long-Term Outcomes Using Propensity Score Matching Analysis

BACKGROUND: It is unclear whether mitral valve (MV) repair for degenerative mitral regurgitation (MR) provides the same advantages in the elderly that it does in the general population. METHODS: From 1994 to 2016, 188 elderly patients (mean age, 68.3±5.50 years) underwent MV repair (n=153) or MV replacement (n=35) for primary degenerative MR. Early and long-term outcomes were compared before and after propensity score matching (PSM). RESULTS: Before PSM, there was a significant difference in operative mortality (p=0.011). Overall survival and freedom from cardiac-related death (CRD) at 5, 10, and 15 years were significantly higher in patients who underwent MV repair (p=0.039 and p=0.007, respectively). In the multivariable analysis, MV replacement was an independent risk factor of CRD. After PSM, operative mortality was not significantly lower in patients who underwent MV repair (p=0.125). Overall survival and freedom from CRD at 5, 10, and 15 years showed no significant difference between the 2 groups in the PSM cohort (p=0.207, p=0.47, respectively). There was no significant difference in freedom from reoperation before or after PSM (p=0.963 and p=0.575, respectively). CONCLUSION: MV repair for primary degenerative MR might be a valid option in the elderly population if successful repair is possible.

Aortic Valve Replacement for Aortic Stenosis in Elderly Patients (75 Years or Older)

BACKGROUND: This study evaluated the early and long-term outcomes of surgical aortic valve replacement (AVR) in elderly patients in the era of transcatheter aortic valve implantation. METHODS: Between 2001 and 2018, 94 patients aged ≥75 years underwent isolated AVR with stented bioprosthetic valves for aortic valve stenosis (AS). The main etiologies of AS were degenerative (n=63) and bicuspid (n=21). The median follow-up duration was 40.7 months (range, 0.6–174 months). RESULTS: Operative mortality occurred in 2 patients (2.1%) and paravalvular leak occurred in 1 patient. No patients required permanent pacemaker insertion after surgery. Late death occurred in 11 patients. The overall survival rates at 5 and 10 years were 87.2% and 65.1%, respectively. The rates of freedom from valve-related events at 5 and 10 years were 94.5% and 88.6%, respectively. The Society of Thoracic Surgeons (STS) score (p=0.013) and chronic kidney disease (p=0.030) were significant factors affecting long-term survival. The minimal p-value approach demonstrated that an STS score of 3.5% was the most suitable cut-off value for predicting long-term survival. CONCLUSION: Surgical AVR for elderly AS patients may be feasible in terms of early mortality and postoperative complications, particularly paravalvular leak and permanent pacemaker insertion. The STS score and chronic kidney disease were associated with long-term outcomes after AVR in the elderly.

Cardiac Magnetic Resonance Predictor of Ventricular Function after Surgical Coronary Revascularization

We evaluated echocardiographic changes of left ventricular (LV) function in coronary artery bypass grafting (CABG) patients with LV dysfunction, and examined cardiac magnetic resonance (CMR) parameters associated with improved LV function. Seventy-seven CABG patients presenting with decreased LV ejection fraction (LVEF, ≤ 35%) and who underwent preoperative gadolinium-enhanced CMR were enrolled. A 16-segment model was used to analyze CMR imaging. A viable myocardial segment was defined as ≤ 50% transmural extent of late gadolinium enhancement. Serial echocardiographic examinations were performed preoperatively, pre-discharge (median 6 days), and during postoperative year 1 (median 11 months) in 70 patients. Predictors of absolute increase in LVEF (≥ 5%) and proportional changes in LVEF were analyzed. Serial echocardiography demonstrated that LVEF measured 28.6% ± 5.4% preoperatively, 31.5% ± 8.0% median 6 days, and 42.1% ± 10.5% median 11 months postoperatively. Absolute increase of LVEF was observed in 27 patients at pre-discharge and in 24 patients by median 11 months. Proportional changes in LVEF at postoperative median 6 days and 11 months were 14% ± 28% and 57% ± 45%, respectively. The median number of viable myocardial segments was 14 (range, 9–16) in the 16 segment CMR model. Multivariable models demonstrated that the median number of overall viable myocardial segments (≥ 14) in preoperative CMR was associated with absolute increase (P = 0.046) and proportional changes (P = 0.005) in LVEF. In conclusion, the number of viable myocardial segments (≥ 14) in preoperative CMR predicted LV function improvement after CABG in patients with LV dysfunction.

Twenty-Year Experience of Heart Transplantation: Early and Long-Term Results

BACKGROUND: We evaluated early and long-term results after heart transplantation (HTPL). METHODS: One hundred five consecutive patients (male:female=80:25) who underwent HTPL between 1994 and 2013 were enrolled. Based on the changes in immunosuppressive regimen, the study patients were divided into two groups. Early and long-term clinical outcomes were evaluated and compared between the patients who underwent HTPL before (group E, n=41) and after July 2009 (group L, n=64). The group L patients were older (p<0.001), had higher incidence of hypertension (p=0.001) and chronic kidney disease (p<0.001), and more frequently needed preoperative mechanical ventilation (p=0.027) and mechanical circulatory support (p=0.014) than the group E patients. RESULTS: Overall operative mortality was 3.8%, and postoperative morbidities included acute kidney injury (n=31), respiratory complications (n=16), reoperation for bleeding (n=15) and wound complications (n=10). There were no significant differences in early results except acute kidney injury between group E and group L patients. Overall survival rates at 1, 5, and 10 years were 83.8%, 67.7%, and 54.9%, respectively, with no significant difference between the two patient groups. Rejection-free rates at 1 and 5 years were 63.0% and 59.7%, respectively; rates were significantly higher in group L than in group E (p<0.001). CONCLUSION: Despite increased preoperative comorbidities, group L patients showed similar early and long-term outcomes and significantly higher rejection-free rates when compared with group E patients.

Surgical Results of Third or More Cardiac Valve Operation

BACKGROUND: We evaluated operative outcomes after third or more cardiac operations for valvular heart disease, and analyzed whether pericardial coverage with artificial membrane is helpful for subsequent reoperation. METHODS: From 2000 to 2012, 149 patients (male:female=70:79; mean age at operation, 57.0+/-11.3 years) underwent their third to fifth operations for valvular heart disease. Early results were compared between patients who underwent their third operation (n=114) and those who underwent fourth or fifth operation (n=35). Outcomes were also compared between 71 patients who had their pericardium open during the previous operation and 27 patients who had artificial membrane coverage. RESULTS: Intraoperative adverse events occurred in 22 patients (14.8%). Right atrium (n=6) and innominate vein (n=5) were most frequently injured. In-hospital mortality rate was 9.4%. Total cardiopulmonary bypass time (225+/-77 minutes vs. 287+/-134 minutes, p=0.012) and the time required to prepare aortic cross clamp (209+/-57 minutes vs. 259+/-68 minutes, p<0.001) increased as reoperations were repeated. However, intraoperative event rate (13.2% vs. 20.0%), in-hospital mortality (9.6% vs. 8.6%) and postoperative complications were not statistically different according to the number of previous operations. Pericardial closure using artificial membrane at previous operation was not beneficial in reducing intraoperative events (25.9% vs. 18.3%) and shortening operation time preparing aortic cross clamp (248+/-64 minutes vs. 225+/-59 minutes) as compared to no-closure. CONCLUSION: Clinical outcomes of the third or more operations for valvular heart disease were acceptable in terms of intraoperative adverse events and in-hospital mortality rates. There were no differences in the incidence of intraoperative adverse events, early mortality and postoperative complications between third cardiac operation and fourth or more.

Post-Coronary Artery Bypass Grafting Myocardial Ischemia Caused by an Overgrown Left Internal Thoracic Artery Side Branch

We present a patient who developed recurrent angina after coronary artery bypass grafting (CABG). Myocardial single-photon emission computed tomography (SPECT) demonstrated deterioration in the myocardial perfusion, and coronary angiography revealed an overgrown side branch of the grafted left internal thoracic artery (ITA); otherwise, there were no significant changes compared with previous imaging studies obtained after the CABG. After percutaneous embolization of the grafted left ITA side branch, the angina was resolved and myocardial SPECT showed improved perfusion.

Percutaneous Extracorporeal Membrane Oxygenation for Graft Dysfunction after Heart Transplantation

BACKGROUND: We evaluated the safety and efficacy of percutaneous extracorporeal membrane oxygenation (ECMO) in patients with primary graft dysfunction after heart transplantation. METHODS: Of 65 patients (44 males and 21 females) who underwent heart transplantation from January 2006 to December 2012, 13 patients (group I) needed peripheral ECMO support due to difficulty in weaning from cardiopulmonary bypass (CPB) and 52 patients (group II) were weaned from CPB without mechanical support. The mean age of the patients at the time of operation was 54.4+/-13.6 years. There were no differences in the preoperative characteristics of the two groups. Multivariable analysis was performed to identify the risk factors for ECMO therapy. RESULTS: All group I patients were successfully weaned from ECMO after 53+/-9 hours of circulatory support. Early mortality occurred in four patients (1 [7.7%] in group I and 3 [5.8%] in group II, p>0.999). There were no differences in the postoperative complications between the two groups, with the exception of reoperation for bleeding. A greater number of group I patients underwent reoperation for bleeding (5 [38.5%] in group I vs. 6 [11.5%] in group II, p=0.035). In multivariable analysis, preoperative mechanical support (ECMO and intra-aortic balloon pump) and longer CPB time were the risk factors of ECMO therapy for graft dysfunction (odds ratio, 6.377; 95% confidence interval, 1.519 to 26.77; p=0.011 and odds ratio, 1.010; 95% confidence interval, 1.001 to 1.019; p=0.033). CONCLUSION: Percutaneous ECMO support could be a viable option for rescuing patients when graft dysfunction refractory to medical management develops after heart transplantation.

Heart Transplantation in a Patient with Persistent Left Superior Vena Cava

A 56-year-old male presented with severe exertional dyspnea and pitting edema in the lower extremities. The pre-operative evaluation demonstrated biventricular dysfunction associated with severe tricuspid valve regurgitation and a persistent left superior vena cava. He was registered as a transplantation candidate, and orthotopic heart transplantation was performed using the standard bicaval technique. The left superior vena cava was connected to the right atrial appendage after the construction of a conduit using the recipient's autologous coronary sinus tissue. One-month postoperatively, computed tomography imagery demonstrated a patent conduit between the left superior vena cava and right atrial appendage.

Impaired Coronary Flow Reserve Is the Most Important Marker of Viable Myocardium in the Myocardial Segment-Based Analysis of Dual-Isotope Gated Myocardial Perfusion Single-Photon Emission Computed Tomography

OBJECTIVE: The aim of this study was to investigate the most robust predictor of myocardial viability among stress/rest reversibility (coronary flow reserve [CFR] impairment), 201Tl perfusion status at rest, 201Tl 24 hours redistribution and systolic wall thickening of 99mTc-methoxyisobutylisonitrile using a dual isotope gated myocardial perfusion single-photon emission computed tomography (SPECT) in patients with coronary artery disease (CAD) who were re-vascularized with a coronary artery bypass graft (CABG) surgery. MATERIALS AND METHODS: A total of 39 patients with CAD was enrolled (34 men and 5 women), aged between 36 and 72 years (mean 58 +/- 8 standard in years) who underwent both pre- and 3 months post-CABG myocardial SPECT. We analyzed 17 myocardial segments per patient. Perfusion status and wall motion were semi-quantitatively evaluated using a 4-point grading system. Viable myocardium was defined as dysfunctional myocardium which showed wall motion improvement after CABG. RESULTS: The left ventricular ejection fraction (LVEF) significantly increased from 37.8 +/- 9.0% to 45.5 +/- 12.3% (p < 0.001) in 22 patients who had a pre-CABG LVEF lower than 50%. Among 590 myocardial segments in the re-vascularized area, 115 showed abnormal wall motion before CABG and 73.9% (85 of 115) had wall motion improvement after CABG. In the univariate analysis (n = 115 segments), stress/rest reversibility (p < 0.001) and 201Tl rest perfusion status (p = 0.024) were significant predictors of wall motion improvement. However, in multiple logistic regression analysis, stress/rest reversibility alone was a significant predictor for post-CABG wall motion improvement (p < 0.001). CONCLUSION: Stress/rest reversibility (impaired CFR) during dual-isotope gated myocardial perfusion SPECT was the single most important predictor of wall motion improvement after CABG.

Clinical Outcomes of Thromboendarterectomy for Chronic Thromboembolic Pulmonary Hypertension: 12-Year Experience

BACKGROUND: We present our 12-year experience of pulmonary thromboendarterectomy in patients with chronic thromboembolic pulmonary hypertension. MATERIALS AND METHODS: Between January 1999 and March 2011, 16 patients underwent pulmonary thromboendarterectomy. Eleven patients (69%) were classified as functional class III or IV based on the New York Heart Association (NYHA) classification. Seven patients had a history of inferior vena cava filter insertion, and 5 patients showed coagulation disorders. Pulmonary thromboendarterectomy was performed during total circulatory arrest with deep hypothermia in 14 patients. RESULTS: In-hospital mortality and late death occurred in 2 patients (12.5%) and 1 patient (6.3%), respectively. Extracorporeal membrane oxygenation support was required in 4 patients who developed severe hypoxemia after surgery. Thirteen of the 14 survivors have been followed up for 54 months (range, 2 to 141 months). The pulmonary arterial systolic pressure and cardiothoracic ratio on chest radiography was significantly decreased after surgery (76+/-26 mmHg vs. 41+/-17 mmHg, p=0.001; 55%+/-8% vs. 48%+/-3%, p=0.003). Tricuspid regurgitation was reduced from 2.1+/-1.1 to 0.7+/-0.6 (p=0.007), and the NYHA functional class was also improved to I or II in 13 patients (81%). These symptomatic and hemodynamic improvements maintained during the late follow-up period. CONCLUSION: Pulmonary thromboendarterectomy for chronic thromboembolic pulmonary hypertension shows good clinical outcomes with acceptable early and long term mortality.

Left Carotid-to-Subclavian Artery Bypass Grafting for Recurrent Angina Caused by Coronary-Subclavian Steal Syndrome

A 60-year-old man visited the outpatient clinic due to one month of recurrent exertional chest pain. Eleven years earlier he had undergone off-pump coronary artery bypass grafting using bilateral internal thoracic artery (ITA) Y-composite grafts based on the left ITA. Preoperative coronary angiography showed patent distal graft anastomoses and visualized the left ITA retrogradely. The arch aortography revealed near-total occlusion of the left subclavian artery at the level of the ostium. The patient underwent left carotid-to-subclavian artery bypass grafting using a 6 mm vascular conduit. Postoperative computed tomographic angiography revealed a patent bypass conduit between the left common carotid artery and left subclavian artery. The patient was discharged on postoperative day 4 with no symptoms or signs of myocardial ischemia.