Ho Jin Kim

Outcomes of Acute Retrograde Type A Aortic Dissection With an Entry Tear in Descending Aorta

Background— Optimal management strategy of acute aortic dissection (AD) with retrograde extension from entry tear in the descending aorta into the ascending aorta remains undetermined. Methods and Results— Of the 538 patients who were diagnosed as having acute AD from 1999 through 2011, 49 patients (37 men; 52.5±13.1 years) were identified as having entry tear in the descending aorta with retrograde extension of AD into the ascending aorta. Sixteen patients who were clinically stable with thrombosed false lumen in the ascending aorta were treated medically (MED group), whereas 33 patients underwent aortic replacement (SURG group) on an intention-to-treat basis. In the MED group, 1 patient was converted to urgent aortic surgery and 2 patients underwent endovascular stent grafting in the descending aorta during the initial hospitalization. The early (30-day or in-hospital) mortality rates were 0% and 9.1% in the MED and SURG group, respectively (P=0.54). Follow-up was complete in all patients (median, 61.4 months; Q1–Q3, 28.2–99.1 months). The 5-year 100% survival rate in the MED group was higher than that in the SURG group (81.2±7.0%; P=0.080), in the surgically treated patients with antegrade type A AD (74.5±2.8%; P=0.038), and in the patients with type B AD (75.3±3.3%; P=0.045). Aortic event–free survival at 5 years was 52.7±14.8% and 69.6±8.0% in the MED and SURG groups, respectively (P=0.98). Conclusions— Patients with acute retrograde type A AD showed a more favorable prognosis than patients with antegrade AD. In selected patients with retrograde type A AD, excellent outcomes could be achieved with initial medical management combined with timely interventions.

Early Postoperative Complications after Heart Transplantation in Adult Recipients: Asan Medical Center Experience

Background Heart transplantation has become a widely accepted surgical option for end-stage heart failure in Korea since its first success in 1992. We reviewed early postoperative complications and mortality in 239 patients who underwent heart transplantation using bicaval technique in Asan Medical Center. Methods Between January 1999 and December 2011, a total of 247 patients aged over 17 received heart transplantation using bicaval technique in Asan Medical Center. After excluding four patients with concomitant kidney transplantation and four with heart-lung transplantation, 239 patients were enrolled in this study. We evaluated their early postoperative complications and mortality. Postoperative complications included primary graft failure, cerebrovascular accident, mediastinal bleeding, renal failure, low cardiac output syndrome requiring intra-aortic balloon pump or extracorporeal membrane oxygenation insertion, pericardial effusion, and inguinal lymphocele. Follow-up was 100% complete with a mean follow-up duration of 58.4±43.6 months. Results Early death occurred in three patients (1.3%). The most common complications were pericardial effusion (61.5%) followed by arrhythmia (41.8%) and mediastinal bleeding (8.4%). Among the patients complicated with pericardial effusion, only 13 (5.4%) required window operation. The incidence of other significant complications was less than 5%: stroke (1.3%), low cardiac output syndrome (2.5%), renal failure requiring renal replacement (3.8%), sternal wound infection (2.0%), and inguinal lymphocele (4.6%). Most of complications did not result in the extended length of hospital stay except mediastinal bleeding (p=0.034). Conclusion Heart transplantation is a widely accepted option of surgical treatment for end-stage heart failure with good early outcomes and relatively low catastrophic complications.

Clinical outcomes in 1731 patients undergoing mitral valve surgery for rheumatic valve disease

Objective Unlike degenerative mitral valve (MV) disease, the advantages of valve repair procedure over replacement have been debated in rheumatic MV disease. This study aims to evaluate the impact of procedural types on long-term outcomes through analyses on a large data set from an endemic area of rheumatic disease. Methods We evaluated 1731 consecutive patients (52.3±12.5 years; 1190 women) undergoing MV surgery for rheumatic MV disease between 1997 and 2015. Long-term survival and valve-related outcomes were compared between repair and replacement procedures. To adjust for selection bias, propensity score analyses were performed. Results Patients undergoing repair were younger and had more predominant mitral regurgitation than mechanical and bioprosthetic replacement groups (61.6% vs 15.6% vs 24.4%; P<0.001). During follow-up (130.9±27.7 months), 283 patients (16.3%) died and 256 patients (14.8%) experienced valve-related complications. Propensity score matching yielded 188 pairs of repair and replacement patients that were well balanced for baseline covariates. In the matched cohort, there was no significant difference in the mortality risk between the repair and replacement groups (HR, 1.24; 95% CI 0.62 to 2.48). The risk of composite valve-related complications, however, was significantly lower in repair group (HR, 0.57; 95% CI 0.33 to 0.99) principally derived by a lower risk of haemorrhagic events (HR, 0.23; 95% CI 0.07 to 0.70). The incidence of reoperation was not significantly different between groups in the matched cohort (HR, 1.62; 95% CI 0.49 to 5.28). Conclusion Valve repair in well-selected patients with severe rheumatic MV disease led to comparable survival, but superior valve-related outcomes compared with valve replacement surgery.

Chronic Sternum Wound Infection Caused by Mycobacterium tuberculosis After Cardiac Surgery

The sternum wound infection, caused by Mycobacterium tuberculosis after a cardiac surgery, is an extremely rare postoperative complication. It requires a high degree of suspicion for a correct diagnosis. Often a successful treatment is impeded by the insidious nature of tuberculosis infection and the time-consuming diagnosis process. We report two cases in which we successfully treated this infection with sternum resection, wound debridement, and antituberculosis medication.

Coronary artery bypass grafting in patients with severe chronic kidney disease: a propensity score-weighted analysis on the impact of on-pump versus off-pump strategies

OBJECTIVES The optimal surgical strategy regarding the use of cardiopulmonary bypass during coronary artery bypass grafting in patients with severe chronic kidney disease remains controversial. METHODS Between 1997 and 2015, we identified 321 consecutive patients with severe chronic kidney disease (Stage 4 or 5) based on the National Kidney Foundation Classification (estimated glomerular filtration rate <30 ml/min/1.73 m2). Of these, on-pump and off-pump coronary artery bypass grafting were performed in 118 and 203 patients, respectively. Surgical outcomes between the 2 groups were analysed after adjustment with propensity scores based on 30 baseline covariates. RESULTS Early mortality occurred in 11 (9.3%) and 2 (1.0%) patients in the on- and off-pump groups, respectively (P = 0.001). The off-pump group had fewer distal anastomoses than the on-pump group (3.1 ± 0.9 vs 2.8 ± 1.0; P = 0.003). After adjustment, the off-pump group showed a significantly lower risk of early death (P = 0.002), sternal wound infection (P = 0.002) and prolonged ventilation (>24 h) (P < 0.001). During the study period, 186 patients died, and the off-pump strategy was associated with a reduced risk of overall mortality (hazard ratio 0.61, 95% confidence interval 0.46-0.81; P < 0.001). On landmark analysis, however, cardiopulmonary bypass use was found to be unassociated with an increased risk of mortality after 1 year (P = 0.198). CONCLUSIONS The on-pump strategy for patients with severe chronic kidney disease was associated with a significantly higher risk of mortality and morbidities, which is particularly attributable to a greater risk of cardiopulmonary bypass use in the early postoperative period. The study result suggests that the off-pump strategy might be beneficial in performing coronary artery bypass grafting, despite potentially incomplete revascularization in this high-risk cohort.

Surgical ablation of atrial fibrillation in patients with a giant left atrium undergoing mitral valve surgery

Objective As the efficacy of surgical ablation for atrial fibrillation (AF) is reported to be suboptimal for patients with a giant left atrium (LA), its routine use on this population has remained controversial. We sought to evaluate the clinical outcomes of patients with a giant LA undergoing mitral valve (MV) surgery with/without the maze procedure. Methods We identified 759 patients with a giant LA (>60 mm) and AF undergoing MV surgery from 1999 through 2012. Of these, 400 underwent MV surgery with the maze procedure (maze group), and the remainder (n=359) underwent MV surgery only (no-maze group). To reduce the impact of selection bias, propensity score analyses were performed based on 25 baseline covariates. Results Early death occurred in five (1.3%) and nine (2.5%) patients in the maze and the no-maze group, respectively (p=0.28). Freedom from AF at 5 years was 68.9% in the maze group and 9.6% in the no-maze group (p<0.001). After adjustment, the maze group showed a significantly lower risk of death (HR, 0.65; 95% CI 0.44 to 0.98; p=0.038), thromboembolic events (HR, 0.23; 95% CI 0.09 to 0.58; p=0.002) and composite adverse outcomes (death, congestive heart failure and valve-related complications; HR, 0.55; 95% CI 0.42 to 0.71; p<0.001) than the no-maze group. In subgroup analyses, MV surgery with the maze procedure resulted in higher survival and event-free survival in most risk subgroups than without the maze procedure. Conclusions The concomitant maze procedure improved postoperative rhythm status, clinical outcomes and cardiac functions in patients with a giant LA undergoing MV surgery. This study indicates that the patients with a giant LA undergoing MV surgery may benefit from an addition of the maze procedure.

Valve replacement surgery for older individuals with preoperative atrial fibrillation: The effect of prosthetic valve choice and surgical ablation

OBJECTIVE Prosthetic valve type selection combined with surgical ablation during left-sided heart valve replacement in older individuals with atrial fibrillation remains controversial. METHODS A total of 573 patients aged 60 years or older (median, 65; range, 60-84) who underwent left-sided valve replacement surgery in the presence of atrial fibrillation from 1990 to 2010 were evaluated for all-cause mortality during a median follow-up period of 58.0 months (interquartile range, 33.1-84.1). RESULTS Mechanical and bioprosthetic valves were implanted in 356 (62.1%) and 217 (37.9%) patients, respectively, and 203 patients (35.4%) underwent surgical ablation concomitantly. During the follow-up period, 166 patients died. The 5- and 10- year survival rate was 76.3% ± 2.1% and 58.4% ± 3.2%, respectively. On Cox regression analysis, age (P < .001), diabetes (P = .014), left ventricular ejection fraction (P = .010), left atrial size (P = .038), the requirement for coronary bypass (P = .015), and cardiopulmonary bypass time (P < .001) emerged as significant and independent predictors of death. In addition, surgical ablation was protective against all-cause mortality (hazard ratio, 0.63; P = .033). The improved survival observed with surgical ablation was verified by propensity score adjustment models (hazard ratio, 0.64; 95% confidence interval, 0.30-0.99; P = .046). The choice of prosthetic type, however, affected neither survival (P = .79) nor event-free survival (P = .48). CONCLUSIONS Long-term survival after valve replacement in older individuals with atrial fibrillation was affected by several preoperative characteristics and the performance of surgical ablation but not by the choice of prosthesis. These findings suggest that surgical atrial fibrillation ablation should always be considered for these patients, regardless of the prosthesis type used.

Recurrent Mediastinal Sarcoma in the Aortic Arch

As mediastinal sarcomas commonly present as large tumors invading adjacent vital structures, complete resection is frequently challenging. For such tumors, aggressive surgical strategies, such as the resection and reconstruction of the invaded vital structures under cardiopulmonary bypass, may be required to achieve complete resection and to improve survival. Herein, we report a case of recurrent mediastinal sarcoma invading the aortic arch and arch vessels that was successfully removed by total arch replacement.

Comparative effectiveness of coronary screening in heart valve surgery: Computed tomography versus conventional coronary angiography

Background: Although conventional coronary angiography (CAG) is considered the gold standard for coronary artery disease (CAD) screening in the setting of heart valve surgery, coronary artery computed tomography angiography (CCTA) has emerged as an alternative modality. This study was conducted to evaluate the clinical outcomes of CCTA compared with conventional CAG for CAD screening in patients undergoing heart valve surgery. Methods: A total of 3150 consecutive patients aged >40 years or with coronary risk factors undergoing elective valve operations between 2001 and 2015 were evaluated. Of these, 1402 patients underwent CCTA (CT group) and 1748 patients underwent conventional CAG (CAG group) for CAD screening. Results: The 30‐day mortality rates were similar in the 2 groups (2.1% in the CT group vs 1.7% in the CAG group; P = .463); however, the incidence of low cardiac output syndrome was higher in the CT group (2.3% vs 1.0%; P = .008). The final rate of detection of significant CAD (≥50% stenosis) (4.9% vs 9.7%; P < .001) and proportion of receiving coronary bypass grafting (CABG) (2.9% vs 4.3%; P = .041) were lower in the CT group. After adjustment by propensity score matching (563 pairs), the main findings of our crude analyses did not change, with lower rates of CAD detection (odds ratio [OR], 0.56; 95% confidence interval [CI], 0.36‐0.85) and CABG (OR, 0.47; 95% CI, 0.26‐0.81), a similar risk of early mortality (OR, 1.51; 95% CI, 0.54‐4.52), but a higher risk of low cardiac output syndrome (OR, 3.30; 95% CI, 1.16‐11.78) in the CT group compared with the CAG group. Conclusions: The detection of significant CAD and identification of candidates for CABG were inferior with CCTA compared with conventional CAG in patients scheduled for elective heart valve operations.

The Treatment of Left Atrial Appendage Aneurysm by a Minimally Invasive Approach

Left atrial appendage (LAA) aneurysm is a rare, pathologic condition that may lead to atrial tachyarrhythmia or thromboembolic events. A 49-year-old man presented with aggravated palpitation and dizziness. He suffered from refractory atrial fibrillation despite a previous history of radiofrequency catheter ablation. Echocardiography revealed a 57-mm LAA aneurysm. Surgical ablation was performed through a right mini-thoracotomy, and the LAA aneurysm was obliterated with a 50-mm AtriClip (Atricure Inc., Westchester, OH, USA). However, follow-up computed tomography showed residual communication, so the patient is still taking warfarin. We report that a minimally invasive strategy for treating LAA aneurysm can be considered, but incomplete closure may occur; thus, caution is needed.