Search

Hybrid ablation combines thoracoscopic epicardial ablation with percutaneous catheter based endocardial ablation for the treatment of AF. The purpose of this study was to evaluate the safety and efficacy of hybrid ablation surgery for the treatment of atrial fibrillation (AF), and to compare outcomes of unilateral vs bilateral thoracoscopic epicardial ablation. Patients with documented AF who underwent hybrid ablation were followed post-operatively for major events. Major events were classified into 2 categories consisting of (1) safety, comprising all-cause mortality and major morbidities, and (2) efficacy, which included recurrence of atrial arrhythmia, cessation of antiarrhythmic drugs (AAD), and completeness of lesion set. A total of 84 consecutive patients were consented for hybrid ablation. Patients presented with an average AF duration of 85.9 months before hybrid ablation. 80 patients underwent successful thoracoscopic epicardial ablation. At 1-year, 87% (60/69) of patients were free from AF and 73% (50/69) were free from AF and off AAD. 63 patients completed both epicardial and endocardial hybrid ablation with posterior wall isolation achieved in 89% (56/63) of patients. Unilateral epicardial ablation was associated with significantly shorter hospital length of stay compared to bilateral surgical approached (3.9 vs 6.7 days, p = 0.002) with no difference in freedom from AF between groups at 1 year. Hybrid ablation for atrial fibrillation is effective for patients at high risk for recurrence after catheter ablation. The unilateral surgical approach may be associated with shorter hospital stay with no appreciable effect on procedure success rates.

BACKGROUND: Identifying high-risk patients who will not derive substantial survival benefit from TAVR remains challenging. Pulmonary hypertension is a known predictor of poor outcome in patients undergoing TAVR and correlates strongly with pulmonary artery (PA) enlargement on CTA. We sought to evaluate whether PA enlargement, measured on pre-procedural computed tomography angiography (CTA), is associated with 1-year mortality in patients undergoing TAVR. METHODS: We retrospectively included 402 patients undergoing TAVR between July 2012 and March 2016. Clinical parameters, including Society of Thoracic Surgeons (STS) score and right ventricular systolic pressure (RVSP) estimated by transthoracic echocardiography were reviewed. PA dimensions were measured on pre-procedural CTAs. Association between PA enlargement and 1-year mortality was analyzed. Kaplan-Meier and Cox proportional hazards regression analyses were performed. RESULTS: The median follow-up time was 433 (interquartiles 339–797) days. A total of 56/402 (14%) patients died within 1 year after TAVR. Main PA area (area-MPA) was independently associated with 1-year mortality (hazard ratio per standard deviation equal to 2.04 [95%-confidence interval (CI) 1.48–2.76], p < 0.001). Area under the curve (95%-CI) of the clinical multivariable model including STS-score and RVSP increased slightly from 0.67 (0.59–0.75) to 0.72 (0.72–0.89), p = 0.346 by adding area-MPA. Although the AUC increased, differences were not significant (p = 0.346). Kaplan-Meier analysis showed that mortality was significantly higher in patients with a pre-procedural non-indexed area-MPA of ≥7.40 cm(2) compared to patients with a smaller area-MPA (mortality 23% vs. 9%; p < 0.001). CONCLUSIONS: Enlargement of MPA on pre-procedural CTA is independently associated with 1-year mortality after TAVR.

BACKGROUND: Surgical ablation for atrial fibrillation (AF) can be effective, yet has mixed results. It is unclear which endocardial lesions delivered as part of hybrid therapy‚ will best augment surgical lesion sets in individual patients. We addressed this question by systematically mapping AF endocardially after surgical ablation and relating findings to early recurrence, then performing tailored endocardial ablation as part of hybrid therapy. METHODS: We studied 81 consecutive patients undergoing epicardial surgical ablation (stage 1 hybrid), of whom 64 proceeded to endocardial catheter mapping and ablation (stage 2). Stage 2 comprised high-density mapping of pulmonary vein (PV) or posterior wall (PW) reconnections, low-voltage zones (LVZs), and potential localized AF drivers. We related findings to postsurgical recurrence of AF. RESULTS: Mapping at stage 2 revealed PW isolation reconnection in 59.4%, PV isolation reconnection in 28.1%, and LVZ in 42.2% of patients. Postsurgical recurrence of AF occurred in 36 patients (56.3%), particularly those with long-standing persistent AF ( P =0.017), but had no relationship to reconnection of PVs ( P =0.53) or PW isolation ( P =0.75) when compared with those without postsurgical recurrence of AF. LVZs were more common in patients with postsurgical recurrence of AF ( P =0.002), long-standing persistent AF ( P =0.002), advanced age ( P =0.03), and elevated CHA 2 DS 2 -VASc ( P =0.046). AF mapping revealed 4.4±2.7 localized focal/rotational sites near and also remote from PV or PW reconnection. After ablation at patient-specific targets, arrhythmia freedom at 1 year was 81.0% including and 73.0% excluding previously ineffective antiarrhythmic medications. CONCLUSIONS: After surgical ablation, AF may recur by several modes particularly related to localized mechanisms near low voltage zones, recovery of posterior wall or pulmonary vein isolation, or other sustaining mechanisms. LVZs are more common in patients at high clinical risk for recurrence. Patient-specific targeting of these mechanisms yields excellent long-term outcomes from hybrid ablation.

Background Depression is a significant concern after cardiac surgery and has not been studied in patients undergoing transcatheter aortic valve replacement (TAVR). We sought to examine the prevalence of pre-procedure depression and anxiety symptoms and explore whether brief bedside cognitive behavioral therapy (CBT) could prevent post-TAVR psychological distress. Methods We prospectively recruited consecutive TAVR patients and randomized them to receive brief CBT or treatment as usual (TAU) during their hospitalization. Multi-level regression techniques were used to evaluate changes by treatment arm in depression, anxiety, and quality of life from baseline to 1 month post-TAVR adjusted for sex, race, DM, CHF, MMSE, and STS score. Results One hundred and forty six participants were randomized. The mean age was 82 years, and 43% were female. Self-reported depression and anxiety scores meeting cutoffs for clinical level distress were 24.6% and 23.2% respectively. Both TAU and CBT groups had comparable improvements in depressive symptoms at 1-month (31% reduction for TAU and 35% reduction for CBT, p = .83). Similarly, both TAU and CBT groups had comparable improvements in anxiety symptoms at 1-month (8% reduction for TAU and 11% reduction for CBT, p = .1). Quality of life scores also improved and were not significantly different between the two groups. Conclusions Pre-procedure depression and anxiety may be common among patients undergoing TAVR. However, TAVR patients show spontaneous improvement in depression and anxiety scores at 1-month follow up, regardless of brief CBT. Further research is needed to determine whether more tailored CBT interventions may improve psychological and medical outcomes.

Severe primary graft dysfunction (PGD) is the leading cause of early postoperative mortality following orthotopic heart transplantation (OHT). Veno-arterial extracorporeal membrane oxygenation (VA-ECMO) has been used as salvage therapy. This study aimed to evaluate the outcomes in adult OHT recipients who underwent VA-ECMO for severe PGD. We retrospectively reviewed 899 adult (≥18 years) patients who underwent primary OHT at our institution between 1997 and 2017. Recipients treated with VA-ECMO (19, 2.1%) exhibited a higher incidence of previous cardiac surgery (p = .0220), chronic obstructive pulmonary disease (p = .0352), and treatment with a calcium channel blocker (p = .0018) and amiodarone (p = .0148). Cardiopulmonary bypass (p = .0410) and aortic cross-clamp times (p = .0477) were longer in the VA-ECMO cohort and they were more likely to have received postoperative transfusion (p = .0013); intra-aortic balloon pump (IABP, p < .0001), and reoperation for bleeding or tamponade (p < .0001). The 30-day, 1-year, and overall survival after transplantation of non-ECMO patients were 95.9, 88.8, and 67.4%, respectively, compared to 73.7, 57.9, and 47.4%, respectively in the ECMO cohort. Fourteen (73.7%) of the ECMO patients were weaned after a median of 7 days following OHT (range: 1–12 days). Following OHT, VA-ECMO may be a useful salvage therapy for severe PGD and can potentially support the usage of marginal donor hearts.

Background Double lung transplantation (DLT) remains the gold standard for end-stage lung disease. Although DLT was historically performed via clamshell thoracotomy, recently the median sternotomy has emerged as a viable alternative. As the ideal surgical approach remains unclear, the aim of our study was to compare the short- and long-term outcomes of these 2 surgical approaches in DLT. Methods We retrospectively reviewed 192 consecutive adult patients who underwent primary DLT at our institution between 2012 and 2017 (sternotomy, n = 147; clamshell, n = 45). The impact of each surgical approach on post-transplant morbidity was investigated, and the overall survival probability analyses were performed. Results There were no significant differences in recipients’ baseline and donors’ characteristics and bilateral allograft ischemic time. Freedom from primary graft dysfunction, acute rejection episodes, postoperative prolonged ventilator support, tracheostomy, postoperative stroke, and airway dehiscence were comparable between these 2 groups. The duration of cardiopulmonary bypass and operative time were significantly longer in the clamshell thoracotomy group. Postoperative extracorporeal membrane oxygenation usage tended to be more frequent in the clamshell thoracotomy group than the median sternotomy group, despite no statistical significance. Length of hospital and intensive care unit stay were not influenced by the type of incision. There was no significant difference in overall survival between these 2 procedure groups (P = .61, log-rank test). Conclusions The median sternotomy approach in DLT decreases operative time and more importantly leads to a shorter duration of cardiopulmonary bypass. The type of surgical approach did not show any statistically significant impact on adult DLT recipients’ morbidity and survival.

Newborn mammals, including piglets, exhibit natural heart regeneration after myocardial infarction (MI) on postnatal day 1 (P1), but this ability is lost by postnatal day 7 (P7). The electrophysiologic properties of this naturally regenerated myocardium have not been examined. We hypothesized that epicardial conduction is preserved after P1 MI in piglets. Yorkshire-Landrace piglets underwent left anterior descending coronary artery ligation at age P1 (n = 6) or P7 (n = 7), After 7 weeks, cardiac magnetic resonance imaging was performed with late gadolinium enhancement for analysis of fibrosis. Epicardial conduction mapping was performed using custom 3D-printed high-resolution mapping arrays. Age- and weight-matched healthy pigs served as controls (n = 6). At the study endpoint, left ventricular (LV) ejection fraction was similar for controls and P1 pigs (46.4 ± 3.0% vs. 40.3 ± 4.9%, p = 0.132), but significantly depressed for P7 pigs (30.2 ± 6.6%, p < 0.001 vs. control). The percentage of LV myocardial volume consisting of fibrotic scar was 1.0 ± 0.4% in controls, 9.9 ± 4.4% in P1 pigs (p = 0.002 vs. control), and 17.3 ± 4.6% in P7 pigs (p < 0.001 vs. control, p = 0.007 vs. P1). Isochrone activation maps and apex activation time were similar between controls and P1 pigs (9.4 ± 1.6 vs. 7.8 ± 0.9 ms, p = 0.649), but significantly prolonged in P7 pigs (21.3 ± 5.1 ms, p < 0.001 vs. control, p < 0.001 vs. P1). Conduction velocity was similar between controls and P1 pigs (1.0 ± 0.2 vs. 1.1 ± 0.4 mm/ms, p = 0.852), but slower in P7 pigs (0.7 ± 0.2 mm/ms, p = 0.129 vs. control, p = 0.052 vs. P1). Overall, our data suggest that epicardial conduction dynamics are conserved in the setting of natural heart regeneration in piglets after P1 MI.

The 6-year Integrated Thoracic Surgery (I-6) residency programs have evolved over the past decade. Despite the rising number of programs, there are minimal data published about the criteria utilized by program directors to select candidates. We analyze the characteristics and qualities of successful matriculants using the American Association of Medical College's (AAMC) data reports and survey responses from program directors.Using a survey administered through the RedCap service, program directors were asked to rate the importance of a variety of factors in their evaluations of candidates. The AAMC data reports from 2018 to 2020 provided information on the mean matriculant research productivity, United States Medical Licensing Examination (USMLE) step 1 scores, and step 2 clinical knowledge (CK) scores.Responses were received from 19 of 33 I-6 programs (58%). Program directors consistently rated interview performance as a very important factor in their evaluation of applicants. Matching into the specialty is becoming more competitive, with mean USMLE step 1, step 2 CK, and research productivity increasing over the past few years; matriculants had mean step 1 and step 2 CK scores of 247.3 and 254.2, respectively, in the 2020 match.Thoracic surgery program directors place high value on applicant interview performance, letters of recommendation, and professionalism. Program directors agree that a forthcoming pass/fail USMLE step 1 score report will lead to closer scrutiny of other factors during the decision-making process and may cause future evaluation of applicants to be heavily reliant on letters of recommendation and medical school pedigree.

We aim to use computational fluid dynamics to investigate the hemodynamic conditions that may predispose to false lumen enlargement in this patient population. Nine patients who received surgical repairs of their type-A aortic dissections between 2017–2018 were retrospectively identified. Multiple contrast-enhanced post-operative CT scans were used to construct 3D models of aortic geometries. Computational fluid dynamics simulations of the models were run on a high-performance computing cluster using SimVascular – an open-source simulation package. Physiological pulsatile flow conditions (4.9 L/min) were used at the aortic true lumen inlet, and physiological vascular resistances were applied at the distal vascular ends. Exploratory analyses showed no correlation between rate of false lumen growth and blood pressure, immediate post-op aortic diameter, or the number of fenestrations (p = 0.2). 1-year post-operative CT scans showed a median false lumen growth rate of 4.31 (3.66, 14.67) mm/year Median (Interquartile range) peak systolic, mid-diastolic, and late diastolic velocity magnitudes were 0.90 (1.40); 0.10 (0.16); and 0.06 (0.06) cm/s respectively. Spearman's ranked correlations between fenestration velocity and 1-year false lumen growth rates were found to be statistically significant: Velocity magnitude at peak systolic (p = 0.025; rho = 0.75), mid diastolic (p = 0.025; rho = 0.75) and late diastolic phases of the cardiac cycle (p = 0.006; rho = 0.85). We have shown that false lumen growth is strongly correlated to fenestration flow velocity, which has potential implications for post-operative surveillance and risk stratification.

This case demonstrates successful surgical management of a 6-cm-long aortoesophageal fistula from an infected stent graft. A 69-year-old woman with a penetrating descending thoracic aortic ulcer underwent endovascular aortic repair. Two weeks later, she presented with nausea and melena, and she was found to have an infected stent graft on imaging. She underwent a two-stage procedure encompassing aortic arch debranching and extra-anatomic aortic bypass in stage 1, and stent graft resection, primary esophageal repair, intercostal and omental flap, and jejunostomy tube placement in stage 2. She was discharged 1 month later and is doing well 1.5 years after the operation.

Background: Heart-lung transplantation (HLTx) is an effective treatment for patients with advanced cardiopulmonary failure. However, no large multicenter study has focused on the relationship between donor and recipient risk factors and post-HLTx outcomes. Thus, we investigated this issue using data from the United Network for Organ Sharing database. Methods: All adult patients (age ≥18 years) registered in the United Network for Organ Sharing database who underwent HLTx between 1987 and 2017 were included (n=997). We stratified the cohort by patients who were alive without retransplant at 1 year (n=664) and patients who died or underwent retransplant within 1 year of HLTx (n=333). The primary outcome was the influence of donor and recipient characteristics on 1-year post-HLTx recipient death or retransplant. Kaplan-Meier curves were created to assess overall freedom from death or retransplant. To obtain a better effect estimation on hazard and survival time, the parametric Accelerated Failure Time model was chosen to perform time-to-event modeling analyses. Results: Overall graft survival at 1-year post-HLTx was 66.6%. Of donors, 53% were male, and the mean age was 28.2 years. Univariable analysis showed advanced donor age, recipient male sex, recipient creatinine, recipient history of prior cardiac or lung surgery, recipient extracorporeal membrane oxygenation support, transplant year, and transplant center volume were associated with 1-year post-HLTx death or retransplant. On multivariable analysis, advanced donor age (hazard ratio [HR], 1.017; P =0.0007), recipient male sex (HR, 1.701; P =0.0002), recipient extracorporeal membrane oxygenation support (HR, 4.854; P P P =0.0007) remained as significant predictors of death or retransplant. These predictors were incorporated into an equation capable of estimating the preliminary probability of graft survival at 1-year post-HLTx on the basis of preoperative factors alone. Conclusions: HLTx outcomes may be improved by considering the strong influence of donor age, recipient sex, recipient hemodynamic status, and transplant center volume. Marginal donors and recipients without significant factors contributing to poor post-HLTx outcomes may still be considered for transplantation, potentially with less impact on the risk of early postoperative death or retransplant.

High-sensitivity Troponin (hs-Tn) has emerged as a useful marker for patients with myocardial injury or heart failure. However, few studies have compared intermediate and hs-Tn in patients undergoing transcatheter aortic valve replacement (TAVR). Moreover, there remains uncertainty of which thresholds are the most useful for discriminating ventricular dysfunction or outcome. In this study we prospectively enrolled 105 patients with severe aortic stenosis (AS) who underwent TAVR as well as blood sampling for high-sensitivity (hs-TnI) and conventional troponin I (EXL-LOCI and RXL) assessment. Patients underwent comprehensive pre-procedure echocardiography. Ventricular dysfunction was defined using left ventricular mass index (LVMI), LV global longitudinal strain (LVGLS) and LV end-diastolic pressure. The mean age was 84.0 ± 8.7 years old and 60% were male sex with mean transaortic pressure gradient of 50.1 ± 16.0 mmHg and AVA of 0.63 ± 0.19 cm2. When using a threshold of 6 ng/L, 77% had positive hs-TnI while 27% had positive hs-TnI using recommended thresholds (16 ng/L for female and 34 ng/L for male). Troponin levels were higher in the presence of abnormal LV phenotypes. The strongest correlate of troponin was LVMI. During median follow-up of 375 days, 21 patients (20%) died. Lower threshold of hs-TnI and EXL-TnI was more discriminatory for overall mortality (Log-rank P = 0.03 for both), while higher threshold of hs-TnI (p = 0.75) and RXL-TnI were not (p = 0.30). Combining hs-TnI and BNP improved to predict long-term outcome (p = 0.004). In conclusion, hs-TnI levels correlated with the degree of LV dysfunction phenotypes. Furthermore, applying a lower threshold for hs-TnI performed better for outcome prediction than a recommended threshold in patients undergoing TAVR. Combining hs-TnI with BNP helped better risk stratification.

Introduction: Spatiotemporal differences in atrial activity are thought to contribute to the maintenance of atrial fibrillation (AF). While recent evidence has identified changes in dominant frequency (DF) during the transition from paroxysmal to persistent AF, little is known about the frequency characteristics of the epicardium during this transition. The purpose of this study was to perform high-resolution mapping of the atrial epicardium and to characterize changes in frequency activity and structural organization during the transition from paroxysmal to persistent AF. Hypothesis: In a porcine model of persistent AF, we tested the hypothesis that the epicardium undergoes spatiotemporal changes in atrial activity and structural organization during persistent AF. Methods: Paroxysmal and persistent AF was induced in adult Yorkshire swine by atrial tachypacing. Atrial morphology was segmented from magnetic resonance imaging and high-resolution patient-specific flexible mapping arrays were 3D printed to match the epicardial contours of the atria. Epicardial activation and DF mapping was performed in four paroxysmal and four persistent AF animals using personalized mapping arrays. Histological analysis was performed to determine structural differences between paroxysmal and persistent AF. Results: The left atrial epicardium was associated with a significant increase in DF between paroxysmal and persistent AF (6.5 ± 0.2 vs. 7.4 ± 0.5 Hz, P = 0.03). High-resolution spatiotemporal mapping identified organized clusters of DF during paroxysmal AF which were lost during persistent AF. The development of persistent AF led to structural remodeling with increased atrial epicardial fibrosis. The organization index (OI) significantly decreased during persistent AF in both the left atria (0.3 ± 0.03 vs. 0.2 ± 0.03, P = 0.01) and right atria (0.33 ± 0.04 vs. 0.23 ± 0.02, P = 0.02). Conclusions: In the porcine model of persistent AF, the epicardium undergoes structural remodeling with increased epicardial fibrosis, reflected by changes in atrial organization index and dominant frequency.

Introduction: The localization of sources responsible for erratic ventricular tachycardia signaling can be facilitated by high-resolution epicardial mapping. Here, we describe an approach for epicardial mapping using 3D printed electrode mapping arrays. We utilize these mapping arrays to perform global beat-to-beat epicardial mapping of ex vivo Langendorff perfused human hearts and demonstrate the ability to identify sources of ventricular tachycardia. Hypothesis: The identification of ventricular tachycardia sources can be facilitated by epicardial mapping with 3D printed flexible mapping arrays. Methods: Epicardial shells were printed using a stereolithography 3D printer using flexible photopolymer resin followed by coupling with custom-designed flexible electrode arrays. Global electroanatomic maps were obtained from Langendorff perfused human hearts during sinus rhythm and after extra stimulus pacing induced ventricular tachycardia. Results: We demonstrate the use of 3D-printed electrode mapping arrays to perform global electroanatomic mapping of the human ventricular epicardium. Flexible 3D printed electrode arrays facilitate high spatial-temporal capture of electrophysiological data in Langendorff perfused human hearts and are capable of identifying epicardial sites of ventricular tachycardia. Conclusions: We report on flexible electrode mapping arrays shaped to match the epicardial contours of the human left and right ventricle. We demonstrate the ability to perform high spatiotemporal resolution mapping of human epicardial signals and demonstrate beat-to-beat global capture of ventricular tachycardia.

Background: Medical treatment for inappropriate sinus tachycardia (IST) remains suboptimal. Radiofrequency Sinus node Modification (RFSM) has been used for managing drug-refractory symptomatic IST. Although, acute success is reasonable, it is faced with high complications and recurrence rates. A novel Sinus Node sparing surgical thoracoscopic hybrid ablation (SUSRUTA) has been recently proposed. Objective: To report outcomes of SUSRUTA for IST patients from a prospective multicenter registry. Methods: This is a multicenter, prospective registry of patients who received SUSRUTA which is SN sparing hybrid ablation using surgical thoracoscopic video-assisted epicardial ablation comprised of a RF bipolar clamp which was used for sparing the SN region (identified by endocardial 3D mapping) and isolation of superior and inferior vena cava with creation of a lateral line across the crista terminalis during IST with isoproterenol challenge. Gaps in the epicardial lesion set are filled in by endocardial RFA. Patients were treated with post op Colchicine and were enrolled in cardiac rehabilitation program. Results: Of the 139 patients, mean age was 26±4 yrs, 91% women and mean duration of IST was 40±21.5 months. 90% were on ivabradine, 86% on beta-blocker, 77% on calcium channel blocker and 77% were on class IC antiarrhythmic agent. Heart rate post-procedure was significantly lower when compared with pre-procedure (110±10 vs. 64±11 bpm, p required a permanent pacemaker. Hospital length of stay was 4.5±0.8 days. At 1041±541 days follow up 94.5% (131/139) were free of symptoms after a single procedure and the 8 patients required a redo-RF catheter ablation.95% patients are off all preprocedural rate controlling medications Conclusion: SUSRUTA appears to be efficacious and safe for the treatment of symptomatic drug resistant IST.

Background The surgical maze is suggested to be effective in persistent atrial fibrillation (AF) by reducing the area for fibrillatory wavelets. However, the mechanism for recurrence and next treatment steps are unclear. Purpose We set out to evaluate the impact of complete transmural epicardial maze lesion sets on the extent atrial organization using novel analyses of wide-area recordings of AF. Methods 19 patients (age 50.9±12.0, 78% male) underwent maze followed by endocardial mapping of AF with a 64-pole basket catheter. Block across roof, floor, and pulmonary vein lesions sets was assessed by high-density voltage mapping and organized zones of AF were assessed by panoramic recordings. Total organized area and mean area of the dominant site were evaluated using automated custom scripts. Results Patients had 3.2±0.9 organized regions in 1 minute of LA recordings. A 54 yo F showed residual conduction to the posterior wall from the roof (purple, Fig. 1A) and a figure-of-8 propagation pattern during AF (arrows, fig B) which terminated with localized ablation (yellow lesions, Fig. 1A, red X, Fig. 1B). Overall, patients with complete block on epicardial lesion set had smaller areas of organization (13.7±8% vs. 45.7±32% of mapped areas, p=0.029) vs. those with gaps. The average size of the dominant area was smaller with complete transmural lines than with gaps (5.7±3% vs. 15.9±10%, p=0.033) (Fig. 1C). Conclusion These results show that complete transmural lesion sets constrain the critical mass available for AF, with smaller resulting organized zones. Future studies that quantify how partitioning the atrial surface affects AF may help personalize lesion sets after maze. Figure 1 Funding Acknowledgement Type of funding source: Public grant(s) – National budget only. Main funding source(s): NIH NRSA F32 United States

Introduction: Newborn piglets reportedly exhibit natural heart regeneration after myocardial infarction (MI). However, the electrophysiologic properties of this regenerated muscle have not been examined. We hypothesized that epicardial electrical conduction is preserved after MI in newborn piglets. Methods: Yorkshire-Landrace piglets underwent left anterior descending coronary artery ligation on postnatal day 1 (P1, n=4) or postnatal day 7 (P7, n=7), infarcting the anteroseptal left ventricle through which the Purkinje conduction system passes. After 7 weeks, cardiac magnetic resonance imaging (MRI) was performed with late gadolinium enhancement for fibrosis analysis. Epicardial conduction mapping was performed using custom 3D-printed, 256-channel high-resolution mapping arrays (Fig 1A). Age- and weight-matched healthy pigs served as controls (n=7). Data are expressed as mean±SD. Results: MRI analysis revealed significant differences between the control, P1, and P7 groups in ejection fraction (47.6±3.1% vs 37.6±3.3% vs 30.2±6.6%, p Conclusion: P1 piglets exhibited incomplete natural cardiac regeneration after MI but nevertheless demonstrated electrophysiologic conservation of epicardial conduction dynamics.

The Stanford classification of aortic dissection was described in 1970. The classification proposed that type A aortic dissection should be surgically repaired immediately, whereas type B aortic dissection can be treated medically. Since then, diagnostic tools and management of acute type A aortic dissection (ATAAD) have undergone substantial evolution. This paper evaluated historical changes of ATAAD repair at Stanford University since the establishment of the aortic dissection classification 50 years ago. The surgical approaches to the proximal and distal extent of the aorta, cerebral perfusion methods, and cannulation strategies were reviewed. Additional analyses using patients who underwent ATAAD repair at Stanford University from 1967 through December 2019 were performed to further illustrate the Stanford experience in the management of ATAAD. While technical complexity increased over time, post-operative survival continued to improve. Further investigation is warranted to delineate factors associated with the improved outcomes observed in this study.

PURPOSE: To investigate the association of aortomitral continuity calcification (AMCC) with all-cause mortality, postprocedural paravalvular leak (PVL), and prolonged hospital stay in patients undergoing transcatheter aortic valve replacement (TAVR). MATERIALS AND METHODS: The authors retrospectively evaluated 329 patients who underwent TAVR between March 2013 and March 2016. AMCC, aortic valve calcification (AVC), and coronary artery calcification (CAC) were quantified by using preprocedural CT. Pre-procedural Society of Thoracic Surgeons (STS) score was recorded. Associations between baseline AMCC, AVC, and CAC and 1-year mortality, PVL, and hospital stay longer than 7 days were analyzed. RESULTS: The median follow-up was 415 days (interquartiles, 344–727 days). After 1 year, 46 of the 329 patients (14%) died and 52 (16%) were hospitalized for more than 7 days. Of the 326 patients who underwent postprocedural echocardiography, 147 (45%) had postprocedural PVL. The CAC score (hazard ratio: 1.11 per 500 points) and AMCC mass (hazard ratio: 1.13 per 500 mg) were associated with 1-year mortality. AVC mass (odds ratio: 1.93 per 100 mg) was associated with postprocedural PVL. Only the STS score was associated with prolonged hospital stay (odds ratio: 1.19 per point). CONCLUSION: AMCC is associated with mortality within 1 year after TAVR and substantially improves individual risk classification when added to a model consisting of STS score and AVC mass only. Supplemental material is available for this article. © RSNA, 2019 See also the commentary by Brown and Leipsic in this issue.

Epithelioid hemangioendothelioma (EHE) is a rare vascular tumor that commonly affects lung, liver, and bone. Among all known EHE cases, only 20% have a pulmonary origin, with metastases to the pericardium occurring in less than 1% of these. Because of its low prevalence, variable presentation, and unknown latency period, a thoracic EHE diagnosis can be easily missed. This case outlines the unique pathologic features of EHE in a patient with cardiovascular disease, provides further insight into diagnosing a rare tumor, and provides a better understanding of the pathophysiology and progression of thoracic EHE.

Purpose Patients undergoing cardiac surgery are at increased risk for heparin-induced thrombocytopenia (HIT). The aim of this study was to identify risk factors and assess the morbidity and mortality associated with HIT in the mechanical circulatory support population. We present a modified “4TMCS” scoring system for this population of patients. MCS represents a “definite” cause of thrombocytopenia and the proposed 4TMCS score replaces the "other causes" category with “Type of mechanical circulatory support”. Methods We performed analysis of patients who underwent cardiac surgery at Stanford University Medical Center between May 1, 2008 and December 31, 2016. Patients were categorized into three groups: 1) Control, patients with normal post-operative platelet count; 2) HIT(-), patients who developed thrombocytopenia and tested negative for HIT; and 3) HIT(+), patients who developed thrombocytopenia and tested positive for HIT. Independent predictors of post-operative HIT were evaluated, and a comparison of diagnostic accuracy between the 4Ts and 4TMCS probability scores was performed. Results We identified 5,314 patients eligible for analysis between 2008 and 2016. In total, 125/5314 (2.4%) patients were diagnosed with HIT, of which 75/5314 (1.4%) had clinical evidence of thrombosis. Overall, in-hospital mortality was 25.6%, 11.7%, and 1.5% in the HIT(+), HIT(-), and control groups, respectively (P Conclusion Heparin-induced thrombocytopenia is associated with worse outcomes and increased morbidity and mortality in patients undergoing cardiac surgery. Patients receiving MCS may be at increased risk for development of post-operative HIT. Awareness of pre-operative patient risk factors and application of a modified 4TMCS probability score may allow for more accurate screening and treatment of HIT in the MCS population.

This report describes the rapid expansion of a previously excluded abdominal aortic aneurysm (AAA) following type A aortic dissection repair in a 74-year-old male. Following successful Hemiarch replacement, CT angiography (CTA) showed residual dissection throughout the thoracoabdominal aorta, which had created a proximal endoleak at the prior endovascular stent graft resulting in the rapid growth of the residual AAA sac. Urgent thoracic endovascular aortic repair (TEVAR) did not fully obliterate false lumen flow allowing further unstable expansion of the AAA and abdominal pain. This was ultimately managed with an open replacement of the infrarenal neck with a Dacron interposition graft sewn to the prior EVAR. Postoperative CTA showed resolution of the false lumen communication to the infrarenal AAA and no further endoleak. Open interposition AAA neck replacement is a possible treatment for new-onset endoleak in patients with aortic dissection following prior infrarenal EVAR.

Thoracic endovascular aortic repair (TEVAR) for aneurysmal chronic dissection is often complicated by retrograde filling of the false lumen and dissected distal landing zone. A “cheese wire”-style fenestration of the dissection intimal flap can create a landing zone facilitating TEVAR. This technique successfully aided TEVAR in 3 patients with an average age of 57.3 years. Complications included type III endoleak requiring relining and renal artery occlusion requiring stent placement. Average duration of clinical follow-up was 19 ± 4 months. Imaging follow-up was 8 ± 10 months. All patients have survived for more than 1 year without aneurysm enlargement.

Heart-lung transplantation is an established therapy for patients with combined end-stage heart and lung failure. However, patients may develop critical, refractory cardiopulmonary decompensation while awaiting suitable donor organs. In these instances, veno-arterial extracorporeal membrane oxygenation (VA-ECMO) may be utilized as salvage therapy to mitigate further deterioration and end-organ dysfunction, and as a bridge to transplantation. Various cannulation configurations have been proposed and utilized to avoid accessing the femoral vessels, specifically to facilitate mobilization and prevent deconditioning. However, in certain instances, femoral cannulation may be most optimal, and efforts must be made to consistently mobilize patients cannulated in this manner. In this case report, we present our experience ambulating a patient femorally cannulated for VA-ECMO while awaiting en-bloc heart-lung transplantation.

See Article by Ad et al In this issue, Ad et al1 report their results with a stand-alone minimally invasive Cox maze procedure. Their sizeable cohort consists of patients with largely long-standing persistent atrial fibrillation (AF).1 Ad et al1 should be congratulated on achieving such excellent surgical results over a long duration with an open-heart surgical procedure. In this group of difficult-to-treat patients, they achieved 78% freedom from atrial arrhythmias off antiarrhythmic drugs after 5 years, using Heart Rhythm Society follow-up guidelines. The patients also had improved quality of life and a remarkably low stroke rate despite the fact that 81% of the patients were eventually taken off anticoagulation. If all patients could be offered a single procedure to achieve 78% success at 5 years with no risk of mortality, the clinics of cardiac surgeons would be filled beyond capacity. Unfortunately, this is not the case, and we should be doing better. The current report adds to the numerous studies in the literature demonstrating that surgical ablation reduces AF burden, is associated with a low postoperative stroke risk, and improves …

The surgical management of atrial fibrillation (AF) is an evolving field with a history of testing various lesion sets and ablation technologies. Previous animal models of AF require a chronic intervention to make AF reliably inducible. Our objective was to create an acute, reliable, and reproducible porcine model of sustained AF. To accomplish this, 21 adult domestic pigs underwent median sternotomy. Methods to induce AF were then performed sequentially: manual stimulation, rapid pacing (200 beats per minute), and then rapid pacing of 8 beats with a cycle length of 300 milliseconds, followed by an extra stimulus at decreasing cycle lengths. If AF was not induced, burst pacing was performed at a cycle length of 90 milliseconds for 30 seconds. If AF was still not induced, intravenous neostigmine was administered, and the process was repeated. Atrial fibrillation was considered sustained after 1 minute. Attempts at AF induction were successful in 18 (86%) of 21. Atrial fibrillation was induced during manual stimulation in four (19%), during rapid pacing in five (24%), during burst pacing in five (24%), and after the administration of neostigmine in four (19%). Mean (SD) duration of AF was 3.6 (2.6) minutes. Of the 18, 14 (78%) reverted to sinus rhythm spontaneously and 4 (22%) required an antiarrhythmic. This technique of inducing AF can easily be used to evaluate new technologies and lesion sets without the need for creating a chronic animal model.

A 76-year-old man with history of critical aortic stenosis was referred for surgical aortic valve replacement. Two months prior, preoperative diagnostic angiogram showed 2-vessel coronary artery disease, including 80% stenosis in midsection of left circumflex (LCX) artery, and serial lesions in the right coronary artery (RCA) with chronic total occlusion (CTO) of the distal segment (Movie I in the Data Supplement; Figure 1A) and significant left to right collateralization. At the time of surgical aortic valve replacement, coronary artery bypass was attempted; however, his saphenous veins were found to be unsuitable to use for bypass. His target vessels were deeply buried into myocardial fat as well. It was the heart team’s decision to bring him back for elective percutaneous coronary intervention (PCI). Unfortunately, 3 weeks after the aortic valve replacement surgery, the patient was admitted to medical service for urosepsis with mild elevation in troponin because of demand ischemia. His transthoracic echocardiogram showed normal left ventricle (LV) function with basal inferior and midseptal wall hypokinesis at this time. Given the elevated troponin and known need to perform complete revascularization, we proceeded to PCI of his 2-vessel disease, including the mid-LCX lesion and the CTO in the large RCA system after he recovered from infection. Figure 1. A , Right coronary artery (RCA) before the percutaneous coronary intervention (PCI) of serial high-grade lesions and chronic total occlusion (CTO). B , RCA immediately after the conclusion of PCI showing successful revascularization of CTO in RCA. C , Repeat coronary angiography after the chest pain and ST-elevation demonstrating patent stents in RCA and occlusion of small posterior descending artery (PDA). D , ECG obtained in recovery …

OBJECTIVES: The effect of atrial fibrillation (AF) on left atrial (LA) function has not been well defined and has been largely based on limited echocardiographic evaluation. This study examined the effect of AF and a subsequent Cox-Maze IV (CMIV) procedure on atrial function. METHODS: Cardiac magnetic resonance imaging (cMRI) was performed in 20 healthy volunteers, 8 patients with paroxysmal atrial fibrillation (PAF) and 7 patients with persistent or long-standing persistent atrial fibrillation (LSP AF). Six of the PAF patients underwent surgical ablation with the CMIV procedure and 5 underwent both pre- and postoperative cMRIs. The persistent or LSP AF patients underwent only postoperative cMRIs because all scans were performed with patients in normal sinus rhythm. Volume–time curves throughout the cardiac cycle and regional wall shortening were evaluated using the cine images and compared across groups. RESULTS: Compared with normal volunteers, patients with PAF had significantly decreased reservoir contribution to left ventricular (LV) filling (P= 0.0010), an increased conduit function contribution (P= 0.04) and preserved booster pump function (P= 0.14). Following the CMIV procedure, significant reductions were noted with respect to reservoir and booster pump function, with corresponding increases in conduit function. These differences were more drastic in patients with persistent/LSP AF. Regional wall motion was significantly reduced by PAF in all wall segments (P< 0.05), but was not further reduced by the CMIV. Despite changes in LA function, LV function was preserved following surgery. CONCLUSIONS: PAF significantly altered LA function and has a detrimental effect on regional wall motion. Surgical intervention further altered LA function, but the reasons for this are likely multifactorial and not entirely related to the lesion set itself.

Redo surgery after prior coronary artery bypass grafting (CABG) is becoming more common. Often, a degenerative, stenotic aortic valve is the primary indication for such an operation. Additionally, a failing mechanical or bioprosthetic valve also necessitates re-operation. These operations present some unique challenges, including safe sternal re-entry, preservation of patent grafts, identification and control of internal mammary artery grafts, and careful planning of the aortotomy. In this report, we describe our technique for conducting this operation safely.

Patients who have received mediastinal radiation therapy (XRT) and subsequently develop severe symptomatic aortic stenosis are at higher risk for post-operative complications with surgical aortic valve replacement (SAVR). Transcatheter aortic valve replacement (TAVR) is an alternative therapy but

A 60-year-old man with cystic fibrosis, mediastinal shift and end-stage kidney disease underwent a heart-lung-kidney transplantation. His explanted heart was used for a domino heart transplantation. This case showed an excellent outcome, even with high preoperative acuity requiring veno-venous extracorporeal membrane oxygenation and continuous veno-venous haemodialysis.

Purpose Clinical and experimental studies have suggested that the powerful mechanical unloading effects caused by left ventricular assist device (LVAD) may induce reverse remodeling of the failing heart. However, the detailed mechanism and process have not been fully elucidated. Recent advances in next generation sequencing has enhanced transcriptomic analysis to quantify gene expression extensively. We aimed to characterize gene expression profiling related with left ventricle (LV) reverse remodeling in failing human heart, before and after HeartWare LVAD (HVAD) implant. Methods Sequencing-based comprehensive analysis of gene expression profiling was performed through next generation sequencing in paired human failing LV samples (n=5; median age, 54 years; 4 men) collected pre- and post- HVAD, as well as non-failing human LV collected from donors (n=8, median age, 41 years; 3 men). Results Overall, mapping of sequencing reads corresponded to 48,162 genes in these human LV samples. Among them, 9,094 differentially expressed genes were found in pre- HVAD compared with non-failing LV, while 6,788 differentially expressed genes were detected in post- HVAD compared with non-failing LV (Figure). The discrepancy in the number of differentially expressed genes between pre- and post- HVAD is associated with the effect caused by HVAD. Furthermore, paired analysis performed between pre- and post- HVAD suggest serum amyloid A1 may contribute a major mechanism of LV reverse remodeling. Conclusion Our proposed analysis identified that the gene expression profiling was markedly influenced in response to HVAD. These results suggest that the altered genes expression during HVAD implantation may play important role in the pathogenesis of heart failure and reverse remodeling.

Purpose Double lung transplantation (DLT) remains the gold standard for end-stage lung disease. While DLT was historically performed via clamshell thoracotomy, recently the median sternotomy has emerged as a viable alternative. As the ideal surgical approach remains unclear, the aim of our study was to compare the short and long-term outcomes of these two surgical approaches in DLT. Methods We retrospectively reviewed 192 consecutive adult patients who underwent primary DLT at our institution between 2012 and 2017 (Sternotomy, n=147; Clamshell, n=45). The impact of each surgical approach on post-transplant morbidity and overall survival probability analysis was performed. Results There were no significant differences in recipients’ baseline and donors’ characteristics and bilateral allograft ischemic time (Table). Freedom from primary graft dysfunction, acute rejection episode, post-operative prolonged ventilator support, tracheostomy, postoperative stroke, and airway dehiscence was comparable between these two groups (p=NS for all). However, the durations of cardiopulmonary bypass (p=0.01) and operative time (p Conclusion The median sternotomy approach in DLT decreases operative time and more importantly leads to a shorter duration of cardiopulmonary bypass. The type of surgical approach did not show any statistically significant impact on adult DLT recipients’ morbidity and survival probability.

ObjectiveThe critical mass hypothesis for atrial fibrillation (AF) was proposed in 1914; however, there have been few studies defining the relationship between atrial surface area and AF. This study evaluated the effect of tissue area and effective refractory period (ERP) on the probability of sustaining AF in an in vivo model.MethodsDomestic pigs (n = 9) underwent median sternotomy. Epicardial activation maps were constructed from bipolar electrograms recorded from form-fitting electrode templates placed on the atria. Baseline ERPs were determined. ERP was lowered with a continuous infusion of acetylcholine (0.005-0.04 mg/Kg/min) until AF could be sustained after burst pacing. The atria were sequentially partitioned using bipolar radiofrequency ablation. ERPs were lowered using acetylcholine until AF could be sustained in each subdivision of atrial tissue. Each subdivision was further divided until AF was no longer inducible. At study completion, the heart was excised and the surface area of each section was measured.ResultsOver a range of ERPs from 75 to 250 ms, the probability of AF was correlated with increasing tissue area (range, 19.5-105 cm2) and decreasing ERP. Logistic regression analysis identified shorter ERP (P

Objective Cryoablation is commonly used at present in the surgical treatment of atrial fibrillation (AF). However, there have been few studies examining the efficacy of the commonly used ablation devices. This report compares the efficacy of two cryoprobes in creating transmural endocardial lesions on the beating heart in a porcine model for chronic AF. Methods In six Hanford miniature swine, the right atrial appendage and the inferior vena cava were isolated using a bipolar radiofrequency clamp to create areas of known conduction block. A connecting ablation line was performed endocardially via a purse string with the novel malleable 10-cm Cryo1 probe for 2 minutes at −40°C. Additional ablation lines were created with the Cryo1 and the 3.5-cm 3011 Maze Linear probe on the right and the left atrial wall. Epicardial activation mapping was performed before and immediately after ablation as well as 14 days postoperatively. Histologic examination was performed 14 days postoperatively. Results Transmural lesions were confirmed in 83/84 cross-sections (99%) for the Cryo1 probe and in 40/41 cross-sections (98%) for the 3011 Maze Linear probe. There was no difference between the devices in lesion width (mean ± SD, Cryo1, 10.7 ± 3.5 mm; 3011, 10.0 ± 3.9mm; P = 0.31), lesion depth (Cryo1, 4.5 ± 1.7 mm; 3011, 4.6 ± 1.5 mm; P = 0.74), or atrial wall thickness (Cryo1, 4.5 ± 1.8 mm; 3011, 4.7 ± 1.7 mm; P = 0.74). There was a conduction delay across the right atrial ablation line (20 ± 2 milliseconds vs 51 ± 8 milliseconds, P < 0.001) that remained unchanged at 14 days (51 ± 8 milliseconds vs 52 ± 10 milliseconds, P = 0.88). Conclusions The Cryo1 probe created transmural lesions on the beating heart, resulting insustained conduction delay. Both probes had a similar performance in lesion geometry in this chronic animal model.

Objective Cryoablation has been used to ablate cardiac tissue for decades and has been shown to be able to replace incisions in the surgical treatment of atrial fibrillation. This in vitro study evaluates the performance of a novel cryoprobe and compares it with existing commercially available devices. Methods A new malleable 10-cm aluminum cryoprobe was compared with a rigid 3.5-cm copper linear probe using in vitro testing to evaluate performances under different thermal loads and with different tissue thicknesses. Radial dimensions of ice formation were measured in each water bath by a high-precision laser 2 minutes after the onset of cooling. Probe-surface temperatures were recorded by thermocouples. Tissue temperature was measured at depths of 4 mm and 5 mm from the probe-tissue interface. Time to reach a tissue temperature of −20°C was recorded. Results Ice formation increased significantly with lower water-bath temperatures (P < 0.001). Width and depth of ice formation were significantly less for the rigid linear probe (P < 0.012 and P < 0.001, respectively). There was no difference between the probes in the maximal negative temperature reached under different thermal loads or at different tissue depths. The malleable probe achieved significantly lower temperatures at the proximal compared with the distal end (–61.7°C vs −55.0°C, respectively; P < 0.001). A tissue temperature of −20°C was reached earlier at 4 mm than at 5 mm (P < 0.001) and was achieved significantly faster with the 3011 Maze Linear probe (P < 0.021). Conclusions The new malleable probe achieved rapid freezing to clinically relevant levels in up to 5-mm–thick tissue. Both probes maintained their performance under a wide range of thermal loads.

Objective The Cox-Maze procedure (CMP) for the surgical treatment of atrial fibrillation (AF) traditionally has required a median sternotomy and cardiopulmonary bypass. This study describes a method using ablation technologies to create the full Cox-Maze lesion set through a 5- to 6-cm right minithoracotomy. Methods Twenty-two consecutive patients underwent a CMP through a right mini-thoracotomy and cardiopulmonary bypass. All patients were followed prospectively with electrocardiogram and 24-hour Holter monitoring at 3, 6, and 12 months. The CMP lesion set was created using bipolar radiofrequency energy and cryotherapy. Results There was no operative mortality or major complications. Two patients required a permanent pacemaker. Five patients (23%) had early atrial tachyarrhythmias. At last follow-up (mean, 18 ± 12 months), all the patients (n = 22) were free from atrial dysrhythmias. At 3 months (n = 19), 84% of patients were off antiarrhythmic drugs. At 6 months (n = 18), 94% of patients were free from AF and off antiarrhythmic medications. At 12 months (n = 16), 81% of patients were free from AF and off antiarrhythmic drugs and three patients remained on warfarin for a mechanical mitral valve. Conclusions A full CMP can be performed through a right mini-thoracotomy with outstanding short-term results. This less invasive procedure can be offered to patients without compromising efficacy.