Direct Extracorporeal Membrane Oxygenation Bridged Heart Transplantation: The Importance of Multi-Organ Failure.

Background and Objectives: Recently, approximately 40% of all heart transplantation (HTx) in South Korea are performed using the direct extracorporeal membrane oxygenation (ECMO) bridging method. We conducted a study to examine the clinical outcome of direct ECMO-bridged HTx and to investigate the impact of multi-organ failure (MOF). Methods: From June 2014 to September 2022, a total of 96 adult patients who underwent isolated HTx at a single tertiary hospital were included in the study. The patients were sub-grouped into ECMO (n=48) and non-ECMO group (n=48), and the ECMO group was subdivided into awake (n=22) and non-awake (n=26) groups based on mechanical ventilator (MV) dependency. Baseline characteristics, 30-day, and 1-year mortality were analyzed retrospectively. Results: The 1-year survival rate was significantly lower in the ECMO group (72.9% vs. 95.8%, p=0.002). There was a significant difference in the 30-day survival rate between the awake and non-awake ECMO groups (81.8% vs. 65.4%, p=0.032). In the univariate analysis of logistic regression for 1-year mortality, the odds ratio was 8.5 for ECMO bridged HTx compared to the non-ECMO group, 12.3 in patients who required MV (p=0.003), and 23 with additional hemodialysis (p<0.001). Conclusions: Patients who required MV in ECMO bridged HTx showed higher preoperative MOF rates and early mortality than those extubated. When considering ECMO bridged HTx, the severity of MOF should be thoroughly investigated, and careful patient selection is necessary.

Influence of hepatic dysfunction in patients who underwent tricuspid valve surgery.

Background: Hepatic dysfunction (HD) is frequently associated with chronic tricuspid regurgitation (TR), and is a risk factor for TR surgery. Late referral of patients with TR is associated with the progression of TR and HD, as well as an increase in surgical morbidity and mortality. Many patients with severe TR suffer from HD; however, their clinical impact is not well documented. Methods: This retrospective review was conducted between October 2008 and July 2017. In total, 159 consecutive patients underwent surgery for TR; 101 with moderate to severe TR were included. We divided patients into N (normal liver function; n=56) and HD (HD; n=45) groups. HD was defined as clinically or radiologically diagnosed liver cirrhosis, or a preoperative Model for End-Stage Liver Disease (MELD)-XI score ≥13. Perioperative data were compared between groups, and changes in the MELD score following TR surgery were estimated in the HD group. Long-term survival rates were analyzed, and analyses were performed to obtain the assessment tool and cutoff value to determine the degree of HD affecting late mortality. Results: The preoperative demographics of both groups were similar, excluding the presence of HD. The EuroSCORE II, MELD score, and prothrombin time international normalization ratio were significantly higher in the HD group, and although early mortality was comparable between groups [N group: 0%, HD group: 2.2% (n=1); P=0.446], intensive care unit and hospital stays were significantly longer in the HD group. The MELD score in the HD group temporarily increased immediately after surgery, and then decreased. The long-term survival rates were significantly lower in the HD group. The most suitable tool for predicting late mortality was the MELD-XI score, with a cutoff value of 13 points. Conclusions: Surgery for patients with severe TR can be performed with relatively low morbidity and operative mortality, regardless of associated HD. MELD scores significantly improved after TR surgery in patients with HD. Even with favorable early outcomes, compromised long-term survival with HD suggests the need to develop an assessment tool that can evaluate the appropriate timing for TR surgery.

The Clinical Outcomes of Marginal Donor Hearts: A Single Center Experience.

BACKGROUND AND OBJECTIVES: Although the shortage of donor is a common problem worldwide, a significant portion of unutilized hearts are classified as marginal donor (MD) hearts. However, research on the correlation between the MD and the prognosis of heart transplantation (HTx) is lacking. This study was conducted to investigate the clinical impact of MD in HTx. METHODS: Consecutive 73 HTxs during 2014 and 2021 in a tertiary hospital were analyzed. MD was defined as follows; a donor age >55 years, left ventricular ejection fraction <50%, cold ischemic time >240 minutes, or significant cardiac structural problems. Preoperative characteristics and postoperative hemodynamic data, primary graft dysfunction (PGD), and the survival rate were analyzed. Risk stratification by Index for Mortality Prediction after Cardiac Transplantation (IMPACT) score was performed to examine the outcomes according to the recipient state. Each group was sub-divided into 2 risk groups according to the IMPACT score (low <10 vs. high ≥10). RESULTS: A total of 32 (43.8%) patients received an organ from MDs. Extracorporeal membrane oxygenation was more frequent in the non-MD group (34.4% vs. 70.7, p=0.007) There was no significant difference in PGD, 30-day mortality and long-term survival between groups. In the subgroup analysis, early outcomes did not differ between low- and high-risk groups. However, the long-term survival was better in the low-risk group (p=0.01). CONCLUSIONS: The outcomes of MD group were not significantly different from non-MD group. Particularly, in low-risk recipient, the MD group showed excellent early and long-term outcomes. These results suggest the usability of selected MD hearts without increasing adverse events.

Impact of Sarcopenia on Outcomes of Minimally Invasive Cardiac Surgery.

Sarcopenia is an objective marker of poor outcome following cardiac surgery through median sternotomy. However, the clinical impact of sarcopenia after minimally invasive cardiac surgery (MICS) has not been well established. This study aimed to analyze the influence of sarcopenia on the early and late outcomes following MICS. We retrospectively examined 1248 patients who underwent MICS via right mini-thoracotomy or upper sternotomy between February 2009 and April 2020. Patients older than 65 years who underwent preoperative computed tomography were enrolled. Sarcopenia was defined as the lowest sex-specific quartile of the body surface area adjusted psoas muscle area. The early operative and late survival outcomes were compared, and the predictor of late composite outcome was analyzed using Cox proportional regression model. Early and late composite outcomes in both groups were also compared. A total of 367 patients were classified into the sarcopenia (n = 92) or non-sarcopenia (n = 275) group. Patients in the sarcopenia group were older, and had lower preoperative hemoglobin and albumin levels. They had higher estimated surgical mortality, but similar early mortality and major morbidity. The survival and late composite outcome were comparable between the two groups. Sarcopenia was neither an independent predictor of late death nor a composite outcome in the multivariable model. After MICS, patients with sarcopenia displayed comparable perioperative outcomes and survival. The clinical impact of sarcopenia on postoperative outcomes might be alleviated by MICS and early recovery protocol after MICS. MICS could be a reasonable approach for elderly patients with sarcopenia.

Surgical Outcomes of Cardiac Myxoma Resection Through Right Mini-Thoracotomy.

Background: With recent advances in cardiac surgery through minimal access, mini-thoracotomy has emerged as an excellent alternative for cardiac myxoma resection. This study analyzed the surgical results of this approach, focusing on postoperative cerebral embolism and tumor recurrence. Methods: We retrospectively reviewed 64 patients (mean age, 56.0±12.1 years; 40 women) who underwent myxoma resection through mini-thoracotomy from October 2008 to July 2020. We conducted femoral cannulation and antegrade cardioplegic arrest in all patients. Patient characteristics and perioperative data, including brain diffusion-weighted magnetic resonance imaging (DWI) findings, were collected. Medium-term echocardiographic follow-up was performed. Results: Thirteen patients (20.3%) had a history of preoperative stroke, and 7 (11.7%) had dyspnea with New York Heart Association functional class III or IV. Sixty-one cases (95.3%) had myxomas in the left atrium. The mean cardiopulmonary bypass and cardiac ischemic times were 69.0±28.6 and 34.1±15.0 minutes, respectively. Sternotomy conversion was not performed in any case, and 50 patients (78.1%) were extubated in the operating room. No early mortality or postoperative clinical stroke occurred. Postoperative DWI was performed in 32 (53%) patients, and 7 (22%) showed silent cerebral embolisms. One patient underwent reoperation for tumor recurrence during the study period; in that patient, a genetic study confirmed the Carney complex. Conclusion: Mini-thoracotomy for cardiac myxoma resection showed acceptable clinical and neurological outcomes. In the medium-term echocardiographic follow-up, reliable resection was proven, with few recurrences. This approach is a promising alternative for cardiac myxoma resection.

A Case of Heart Transplantation for Fulminant Myocarditis After ChAdOx1 nCoV-19 Vaccination.

Vaccines have become the mainstay of management against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection (coronavirus disease 2019; COVID-19) in the absence of effective antiviral therapy. Various adverse effects of COVID-19 vaccination have been reported, including cardiovascular complications such as myocarditis or pericarditis. Herein, we describe clinical records of a 63-year woman with fulminant myocarditis following ChAdOx1 nCoV-19 vaccination that was salvaged by heart transplantation. She complained chest pain, nausea, vomiting, and fever after the second vaccination. After the heart transplantation, the patient died due to necrotizing pneumonia on the 54th day of onset. Fulminant myocarditis is very rare after ChAdOx1 nCoV-19 vaccination but can be fatal.

Comparison of del Nido and histidine-tryptophan-ketoglutarate cardioplegic solutions in minimally invasive cardiac surgery.

OBJECTIVE: We examined the safety and efficacy of del Nido cardioplegic solution compared with histidine-tryptophan-ketoglutarate cardioplegic solution in minimally invasive cardiac surgery. METHODS: Patients who underwent minimally invasive cardiac surgery using del Nido or histidine-tryptophan-ketoglutarate from 2015 to 2019 were enrolled. Various clinical outcomes were compared between the groups. Postoperative laboratory findings including the levels of electrolytes, cardiac enzymes (creatine kinase-MB and troponin I), and serial blood lactate were also measured and compared. Based on 28 baseline covariates, propensity score matching was performed to reduce selection bias. RESULTS: Among 766 patients, del Nido and histidine-tryptophan-ketoglutarate were used in 330 patients (43.1%) and 436 patients (56.9%), respectively. There were no significant intergroup differences in postoperative clinical outcomes and early adverse outcomes among 228 pairs of propensity score-matched patients. Immediate postoperative sodium levels were within the normal range in both groups without a significant difference (P = .50). However, peak creatine kinase-MB (median, 31.9 vs 37.7 ng/mL, P = .026) and troponin I (6.9 vs 9.1 ng/mL, P = .014) levels were significantly lower in the del Nido group. Linear regression analysis revealed a significant association between the peak cardiac enzyme levels and the cardiac ischemic time depending on the cardioplegia type, with lower cardiac isoenzymes for del Nido over histidine-tryptophan-ketoglutarate (P < .001) until the crossover point at the cardiac ischemic time over 100 minutes. CONCLUSIONS: In comparison with histidine-tryptophan-ketoglutarate solution, del Nido solution seems to have acceptable safety and efficacy with good myocardial protection in minimally invasive cardiac surgery. Further studies focusing on complex surgeries requiring longer cardiac ischemic time are needed.

3-Dimensional computed tomographic assessment predicts conduction block and paravalvular leakage after rapid-deployment aortic valve replacement.

OBJECTIVES: Complications like complete atrioventricular block (CAVB) and paravalvular leakage (PVL) following rapid deployment aortic valve (AV) replacement (RDAVR) remain unresolved. Selecting an optimal size of the valve might be important to minimize the incidence of these complications. We sought to determine the impact of prosthesis size relative to the anatomic profile of the AV on the occurrence of CAVB or PVL after RDAVR. METHODS: Preoperative computed tomographic (CT) images were evaluated in patients receiving RDAVR (INTUITY ELITE) between February 2016 and December 2019. The occurrence of CAVB requiring permanent pacemaker implantation and PVL (≥ mild) was evaluated. The relative size of implants against the cross-sectional dimensions of recipients' AV annulus and left ventricular outflow tract (LVOT) were calculated. RESULTS: Among 187 eligible patients, CAVB and PVL (≥ mild) occurred in 12 (6.4%) and 11 patients (5.9%), respectively. CAVB was associated with oversized RDAVR (RDAVR frame width minus average diameter of LVOT calculated from the cross-sectional area [ΔLVOTarea]: odds ratio, 2.05; 95% confidence interval, 1.28-3.30): this was with an area under the curve of 0.78 (P = 0.005). The projected probability of CAVB was <3% when the ΔLVOTarea was <1.3. In contrast, PVL was associated with under-sized RDAVR (RDAVR size divided by the longest diameter of AV annulus [index Annlong]: odds ratio, 0.64; 95% confidence interval, 0.51-0.79): This was with an area under curve of 0.94 (P < 0.001). CONCLUSIONS: CT parameters of the AV annulus and LVOT are highly reliable in the prediction of CAVB or PVL after RDAVR. Our data might justify CT-based sizing of prosthesis for RDAVR.

Control of Femoral Cannulation with a ProGlide Pre-Closure Device during Cardiac Surgery: Is It Reliable?

BACKGROUND: The use of ProGlide as a percutaneous vascular closure device in cardiac surgery remains inconclusive. This study investigated the clinical outcomes of using Pro- Glide in the percutaneous cannulation of femoral vessels in adult cardiac surgery. METHODS: From September 2017 to July 2018, 131 consecutive patients underwent femoral vessel cannulation during cardiac surgery. The ProGlide (Abbott Vascular Inc., Santa Clara, CA, USA) with percutaneous cannulation was used in 118 patients (mean age, 55.7±15.5 years). The accessibility of femoral cannulation was evaluated through preoperative computed tomography. For cannulation, sonography was routinely used. The postoperative ankle-brachial index (ABI) was used to evaluate femoral artery stenosis. RESULTS: Of the 118 patients, 112 (94.9%) and 6 (5.1%) underwent minimally invasive cardiac surgery and median sternotomy, respectively. Most femoral cannulations were performed on the right side (98.3%) using 15F to 19F arterial cannulas. The technical success rate of cannulation with ProGlide was 99.2%, with no delayed bleeding or cannulation site-related complications during hospitalization. During follow-up, only 1 patient showed femoral artery stenosis with claudication and was treated with interventional balloon angioplasty. The postoperative ABI revealed no significant difference in functional stenosis between the cannulation and non-cannulation sides (n=86; cannulation vs. non-cannulation, 1.2±0.1 vs. 1.1±0). CONCLUSION: Percutaneous femoral cannulation with ProGlide was safe and feasible in adult cardiac surgery. This technique may be a good alternative option in patients requiring femoral vessel cannulation for cardiac surgery.

Early experience of pump-controlled retrograde trial off for weaning from veno-arterial extracorporeal membrane oxygenation in adult patients with cardiogenic shock.

INTRODUCTION: Pump-controlled retrograde trial off has recently been introduced as an effective method for weaning from veno-arterial extracorporeal membrane oxygenation in pediatric patients. However, studies on pump-controlled retrograde trial off in adults are still lacking. Thus, this study aimed to examine the outcomes of pump-controlled retrograde trial off for weaning from veno-arterial extracorporeal membrane oxygenation in adult patients. METHODS: Between January 2018 and July 2019, 87 consecutive adult patients underwent veno-arterial extracorporeal membrane oxygenation support, of whom 47 (54.0%) underwent pump-controlled retrograde trial off for weaning from extracorporeal membrane oxygenation and were enrolled in this study. The pump-controlled retrograde trial off results, extracorporeal membrane oxygenation reapplication rate, and clinical outcomes were analyzed. RESULTS: Of the 47 patients, 38 (80.9%) were weaned from veno-arterial extracorporeal membrane oxygenation on the first attempt of pump-controlled retrograde trial off, 5 (10.6%) on the second attempt, and 4 (8.5%) on the third attempt. Three patients were converted to venovenous extracorporeal membrane oxygenation by desaturation but had stable blood pressure during pump-controlled retrograde trial off. No extracorporeal membrane oxygenation reapplication was performed within 3 days after removal, and two patients underwent veno-arterial extracorporeal membrane oxygenation during follow-up. No complications associated with pump-controlled retrograde trial off occurred during the weaning process, including thromboembolic events. Five in-hospital deaths (10.6%) occurred after weaning from extracorporeal membrane oxygenation. CONCLUSION: Pump-controlled retrograde trial off is an effective method to safely wean from veno-arterial extracorporeal membrane oxygenation in adult patients. It is simple and can be easily implemented without additional invasive procedures and may help prevent deterioration of the cardiovascular system after weaning from veno-arterial extracorporeal membrane oxygenation.

Simple Interrupted Suturing for Aortic Valve Replacement in Patients with Severe Aortic Stenosis.

BACKGROUND: Attaining an adequate effective orifice area (EOA) is definitive goal in aortic valve replacement (AVR). The simple interrupted suture (SIS) technique could be a solution to achieve this goal, but limited data are available in the literature. This study aimed to compare hemodynamic differences between the SIS and non-everting mattress suture (NMS) techniques. METHODS: From our database, 215 patients who underwent AVR for severe aortic stenosis were extracted to form the overall cohort. From March 2015 to November 2016, the SIS technique was used in 79 patients, while the NMS technique was used in 136 patients. Hemodynamic outcomes were evaluated, as detected by transthoracic echocardiography and computed tomography. RESULTS: There were no significant differences in baseline characteristics between the 2 groups. On immediate postoperative echocardiography, the SIS group showed a significantly wider EOA (1.6±0.4 vs. 1.4±0.5 cm2, p=0.007) and a lower mean pressure gradient (PG) (13.3±5.4 vs. 17.0±6.0 mm Hg, p<0.001) than the NMS group. On follow-up echocardiography, the SIS group continued to have a wider EOA (1.6±0.4 vs. 1.4±0.3 cm2, p<0.001) and a lower mean PG (11.0±5.1 vs. 14.1±5.5 mm Hg, p<0.001). There was no significant difference in paravalvular leakage. CONCLUSION: The SIS technique for AVR was associated with a wider EOA and a lower mean PG. The SIS technique could be a reasonable option for AVR.

Use of a pectus bar for surgical stabilization of cardiopulmonary resuscitation induced flail chest.

A flail chest can occur when cardiopulmonary resuscitation causes extensive rib fractures. Despite successful cardiopulmonary resuscitation, if the flail chest is not treated, the patient may not survive regardless of the correction of the primary condition that caused the cardiac arrest. Therefore, if flail chest persists despite the appropriate conservative management to correct the flail chest, active surgical management is essential. We present a successful surgical treatment with a pectus bar for a patient with flail chest, caused by extensive segmental rib fractures sustained during cardiopulmonary resuscitation for a massive pulmonary thromboembolism.

Cardiac myxoma misdiagnosed as infective endocarditis: a case of Carney complex.

BACKGROUND: Infective endocarditis and cardiac myxoma have common features including fever, systemic embolism and intra-cardiac masses. For this reason, these diseases are often misdiagnosed one for another despite proper imaging studies. Herein, we report a case of suspected infective endocarditis in a patient with acute stroke, fever and a mass adjacent to the mitral valve. CASE PRESENTATION: A 24-year-old male patient presented with recurrent fever and stroke. In view of a history of Cushing syndrome and a mobile mass in the left atrium, infective endocarditis was highly suspected. He was transferred for emergency cardiac surgical intervention. During surgery, intraoperative transesophageal echocardiography revealed a 7 cm mass attached to the interatrial septum. The mass was excised through right mini-thoracotomy and pathological examination confirmed the presence of a myxoma. Based on the above clinical findings and genetic analysis, the diagnosis of Carney complex was confirmed. CONCLUSIONS: Infective endocarditis and cardiac myxoma have common features and can be misdiagnosed. If a young patient presenting with embolic stroke had a history of an endocrine neoplasm, Carney complex should be considered in the differential diagnosis of infective endocarditis.

Incidence and Distribution of Cerebral Embolism After Cardiac Surgery According to the Systemic Perfusion Strategy　- A Diffusion-Weighted Magnetic Resonance Imaging Study.

BACKGROUND: Stroke is a major concern in minimally invasive cardiac surgery, so we investigated the incidence and risk factors of cerebral embolism according to the systemic perfusion strategy under thorough imaging assessment.Methods and Results:Between November 2011 and May 2015, 315 cardiac surgery patients who underwent preoperative computed tomography angiography (CTA) as a routine evaluation were enrolled. The incidence and distribution of cerebral embolism were analyzed with routine postoperative brain diffusion-weighted magnetic resonance imaging (DW-MRI) examination. Anterograde perfusion was used in 103 patients (group A), and retrograde perfusion was performed in 212 patients (group R). Operative deaths, incidence of clinical stroke (group A: 0%, group R: 0.5%, P=0.77), and rate of cerebral embolism (group A: 35.9%, group R: 26.4%, P=0.08) were comparable. The median number of new embolic lesions detected by MRI per patient (group A: 2, group R: 2, P=0.16), maximal diameter of the lesion (group A: 6.5 mm, group R: 6.0 mm, P=0.97), and anatomic distribution of the lesion were similar between groups. In the multivariate analysis, hypertension, emergency status, atherosclerosis grade 3 or 4 (intimal thickening >4 mm), and cardiopulmonary bypass time were independent risk factors for postoperative cerebral embolism, but retrograde perfusion was not. CONCLUSIONS: According to the results of postoperative DW-MRI, retrograde perfusion itself might not increase the incidence of postoperative cerebral embolism in properly selected cardiac surgery patients undergoing routine preoperative CTA examination.

Robotic-Assisted Surgical Ablation of Atrial Fibrillation Combined With Mitral Valve Surgery.

BACKGROUND: Data on robotic-assisted surgical atrial fibrillation (AF) ablation in patients undergoing mitral valve (MV) operations are lacking. This study aimed to evaluate early and late outcomes after robotic-assisted ablation of AF combined with MV surgery. METHODS: Between 2007 and 2017, this study enrolled 94 patients (age: 53.9 ± 12.7 years; 67 men) undergoing AF ablation by using an argon-based flexible cryoablation system during robotic-assisted MV surgical procedures. Persistent (n = 34, 36.2%) or long-standing persistent (n = 38, 40.4%) AF was present in most patients. Primary valve procedures included isolated mitral repair in 58 patients, isolate mitral replacement in 2 patients, and combined mitral and tricuspid repair in 34 patients. RESULTS: Sixty patients (63.8%) received left-side-only AF ablation, whereas the others (n = 34, 36.2%) received biatrial ablation. The operation times for cardiopulmonary bypass and aortic cross-clamping were 222.7 ± 57.8 minutes and 134.1 ± 30.4 minutes, respectively. No early death was seen. Major early complications included neurologic injury in 2 patients (2.1%) and low cardiac output syndrome in 2 patients (2.1%). No patients required permanent pacemaker implantation. Early AF occurred in 14 patients (14.9%) during a postablation blanking period (90 days). During a median follow-up of 49.6 months (quartiles 1 to 3: 17.2 to 79.4 months, 95.7% complete), there were two late deaths (0.49% per patient-year) and one stroke (0.25% per patient-year). Five-year survival was greater than 96%, and results from largely electrocardiograms showed a low recurrence of AF (2.2% at 1 year, 6.7% at 5 years). CONCLUSIONS: Surgical AF ablation with the use of robotic-assistance in the setting of mitral valve surgery showed excellent safety and favorable long-term clinical outcomes.

Myocardial injury following aortic valve replacement for severe aortic stenosis: risk factor of postoperative myocardial injury and its impact on long-term outcomes.

BACKGROUND: As hypertrophied myocardium predisposes the patient to decreased tolerance to ischemia and increased reperfusion injury, myocardial protection is of utmost importance in patients undergoing aortic valve replacement (AVR) for severe aortic valve stenosis (AS). METHODS: Consecutive 314 patients (mean age, 62.5±10.8 years; 143 females) with severe AS undergoing isolated AVR were included. Postoperative myocardial injury (PMI) was defined as 1) maximum postoperative creatinine kinase isoenzyme MB or troponin-I levels ≥10 times of reference, 2) postoperative low cardiac output syndrome or episodes of ventricular arrhythmia, or 3) left ventricular ejection fraction of less than 55% and decrease in left ventricle (LV) ejection fraction of more than 20% of the baseline value. RESULTS: There were 90 patients (28.7%) who developed PMI. There were five cases of early death (1.6%), all of whom had PMI. On multivariable analysis, the use of histidine-tryptophan-ketoglutarate (HTK) solution instead of blood cardioplegia (odds ratio [OR], 3.06; 95% confidence interval [CI], 1.63 to 5.77; p=0.001), greater LV mass (OR, 1.04; 95% CI, 1.01 to 1.07; p=0.007), and increased cardiac ischemic time (OR, 1.13; 95% CI, 1.05 to 1.22; p<0.001) were independent predictors for PMI. Patients who had PMI showed significantly inferior long-term survival than those without PMI (p=0.049). CONCLUSION: PMI occurred in a considerable proportion of patients undergoing AVR for severe AS and was associated with poor long-term survival. HTK cardioplegia, higher LV mass, and longer cardiac ischemic duration were suggested as predictors of myocardial injury.