Multilayer Perceptron Neural Network Analysis of Fluoroscopic Working Angle on Transcatheter Aortic Valve Implantation Complications.

BACKGROUND: We sought to determine whether there is a relationship between the fluoroscopic working angle used to achieve a co-planar view during the deployment of the prosthesis during transcatheter aortic valve implantation (TAVI) and rates of complications, including paravalvular leaks, complete heart block, annular rupture, stroke, valve embolization, discharge to a skilled nursing facility and death within thirty days. METHODS: All patients undergoing TAVI at our institution from 2015 to 2022 were retrospectively analyzed. Images were reviewed to determine the fluoroscopic working angle during deployment, and medical records were used to determine the incidence and type of complication. A multilayer perceptron was employed to evaluate the predictive ability of the fluoroscopic working angle during deployment on complications of one-day and 30-day paravalvular leak, 30-day mortality, the need for a new pacemaker, discharge to a skilled nursing facility, stroke and the requirement for emergency intervention. RESULTS: Eight hundred and thirty-four patients were included in the study. Fluoroscopic working angle had excellent predictive value for stroke (area under the receiver operating characteristic curve (AUROC) of 0.812), one-day (AUROC 0.850), and 30-day paravalvular leak (AUROC 0.801). However, feature importance and scaled weighting analysis indicated that only a working angle in the left anterior oblique/cranial quadrant was informative for the development of an outcome of interest specific to a working angle quadrant (30-day paravalvular leak). CONCLUSION: Fluoroscopic working angle may be a useful way to further refine well-established risk calculi during TAVI.

Outcomes of coronary artery bypass surgery using modified del Nido cardioplegia in patients with poor ventricular function.

BACKGROUND: del Nido cardioplegia (DN) has been shown to be safe in adult patients undergoing isolated coronary artery bypass grafting with normal left ventricular ejection fraction. We sought to determine whether it was also safe in adult patients with diminished left ventricular function. METHODS: All patients with preoperative left ventricular ejection fraction ≤ 40% undergoing isolated coronary artery bypass grafting between 1/1/2019 and 7/10/2022 were retrospectively analyzed. Off-pump and beating heart cases were excluded. Patients were divided by surgeon preference between conventional cardioplegia (CCP) and DN. Baseline and intraoperative characteristics and short-term postoperative outcomes were compared. RESULTS: Six surgeons performed 829 isolated coronary artery bypass operations during the study. Two-hundred seventy-two met study criteria. Three surgeons used exclusively CCP for the duration of the study, two used exclusively DN and one switched from CCP to DN mid-way through. Group totals were: CCP n = 181 and DN n = 91. There were no significant differences in baseline characteristics including mean left ventricular ejection fraction (CCP 32.5 ± 7.4% vs. DN 33.4 ± 7.29%, p = 0.939). Other than a significant decrease in bypass time for DN (113.20 ± 37.2 vs. 122.43 ± 34.3 min, p = 0.043) there were no intergroup differences in urgency, number of grafts, ischemic time or incidence of blood transfusion. Postoperative outcomes between CCP and DN were similar including incidence of atrial fibrillation (12.2% vs. 8.8%, p = 0.403), intensive care length of stay (3.7 ± 2.3 vs. 4.3 ± 3.7 days, p = 0.886), total length of stay (5.7 ± 3.7 vs. 6.3 ± 4.4 days, p = 0.922) and 30-day mortality (3.85% vs. 1.10%, p = 0.205). CONCLUSION: Compared to conventional cardioplegia, del Nido cardioplegia provides equivalent short-term outcomes in patients with low left ventricular ejection fraction undergoing isolated coronary artery bypass grafting.

Giant Aneurysm of Left Main Coronary Artery in a Patient With Prior Operation for 4-Valve Endocarditis.

Left main coronary artery aneurysm is an unusual complication of infective endocarditis. Although this type of aneurysm is often asymptomatic, rupture and thrombus formation that result in myocardial infarction are known complications; therefore, prompt recognition and surgical intervention are warranted. This report describes a patient who presented with a giant left main coronary artery aneurysm 3.5 years after being treated for 4-valve endocarditis. The management and technical aspects of this challenging case are discussed here.

Current status of perioperative temporary mechanical circulatory support during cardiac surgery.

OBJECTIVES: We sought to determine utilization and outcomes of perioperative temporary mechanical circulatory support (tMCS) in the current practice of cardiac surgery. BACKGROUND: tMCS is an evolving adjunct to cardiac surgery not fully characterized in contemporary practice. METHODS: Using the nationwide inpatient sample we retrospectively analyzed hospital discharge data between January 1, 2016 and December 31, 2019. ICD-10-CM procedure codes were used to identify and divide patient hospitalizations into those who had preoperative tMCS (pre-tMCS) versus tMCS instituted the day of surgery or afterwards (sd/post-tMCS). RESULTS: In all, 1,383,520 hospitalizations met inclusion criteria. 86,445 (6.25%) had tMCS. tMCS was utilized in 8.74% of coronary artery bypass grafting (CABG), 2.58% of isolated valve, and 9.71% of valve/CABG; operations. 29,325 (33.9%) had pre-tMCS while 57,120 (66.1%) had sd/post-tMCS. The use of tMCS was associated with greater inpatient mortality (15.66% vs. 1.53%, p < .001), longer length of stay (LOS) (14.4 vs. 8.5 days, p < .001), and higher mean inflation-adjusted costs ($93,040 ± 1038 vs. $51,358 ± 296, p < .001) compared to no use. Inpatient mortality (5.98% vs. 20.63%, p < .001), LOS (13.87 vs. 14.68, p < .001), and cost ($82,621 ± 1152 SEM vs. $98,381 ± 1242) were all significantly lower with pre-tMCS compared to sd/post tMCS. When analyzed separately, mortality was higher with later utilization of tMCS (5.98% pre, 17.1% sd, and 49.05% postsurgical date insertion, p < .001). CONCLUSIONS: Perioperative tMCS is utilized in 6.25% of modern cardiac surgery, with two-thirds of cases instituted on the day of surgery or afterwards. The use of tMCS is associated with significantly higher mortality, longer LOS, and higher costs. Among patients undergoing tMCS, earlier utilization is associated with better outcomes.

Impact of the heart transplant allocation policy change on inpatient cost of index hospitalization.

BACKGROUND: We sought to determine the financial impact of the United Network for Organ Sharing heart transplant (HT) allocation policy change of October 2018. METHODS: Using the Nationwide Inpatient Sample we retrospectively analyzed hospital discharge data between January 1, 2016 and December 31, 2019. ICD-10-CM procedure codes were used to identify hospitalizations of patients undergoing HT as well as the use of temporary mechanical circulatory support (MCS) during the HT hospitalization. Patients < 18 years old and those with missing data on costs were excluded. The primary outcome was inflation-adjusted costs. Total costs were inflated to 2019 US dollars. RESULTS: During the course of the study, temporary MCS increased significantly among 11 380 weighted patients transplanted while mean length of stay (LOS) did not. Mean inflation-adjusted costs rose about $40k per HT. On univariate analysis, transplantation year, use of temporary MCS and LOS were all significantly associated with increased cost while on multivariate analysis only temporary MCS and LOS were. CONCLUSIONS: The 2018 allocation change has resulted in more expensive inpatient costs for HT correlating with an increase in temporary MCS.

The effect of recipient BMI on waitlist and post-transplant outcomes after the 2018 heart transplant allocation policy change.

OBJECTIVE: The effects of recipient body mass index (BMI) on waitlist strategies, waitlist outcomes, and post-transplant outcomes among adult patients listed for heart transplantation under the updated 2018 allocation system have not been well characterized. METHODS: The United Network of Organ Sharing data set between October 2015 and March 2021 was analyzed, and patients were grouped based on recipient BMI and whether listing occurred in the old (pre-October 2018) or new allocation system. RESULTS: Listing strategies differed by BMI group, but trends of increased use of temporary mechanical support and decreased use of durable support remained among all BMI groups, except those with BMI > 35 kg/m2 . Waitlist outcomes improved among all BMI cohorts in the new allocation system, including among patients with BMI 30-34.9 and >35 kg/m2 , although patients with higher BMIs continued to have longer waitlist times. Post-transplant outcomes in the new allocation system are worse for patients with BMI > 30 kg/m2  (hazard ratio: 1.47; confidence interval: 1.19-1.82; p < .001). CONCLUSIONS: The 2018 change to the heart transplant allocation system was associated with similar changes in the use of mechanical support for listing strategy across BMI ranges, except in the most obese, and improved waitlist outcomes across all BMI ranges. Post-transplant outcomes in the new allocation system are worse for patients with BMI > 30 kg/m2  compared to patients with BMI < 30 kg/m2 . These findings have important clinical implications for our understanding of the ongoing influence of BMI on waitlist courses and post-transplant outcomes among patients listed for heart transplantation.

Coronary artery aneurysm, ectasia and stenosis in a 53-year-old man with HIV infection.

The impact of long-standing human immunodeficiency virus infection (HIV) and potent anti-retroviral therapy on the coronary circulation is unknown; however, scattered reports are emerging of coronary aneurysms in this population. We report what we believe to be the first described case of both coronary stenosis and coronary artery aneurysms in a person living with HIV and discuss management options.

Hemorrhagic pericardial effusion resulting in constriction in hereditary hemorrhagic telangiectasia.

BACKGROUND: We report the first ante-mortem diagnosis of hemorrhagic pericardial effusion in hereditary hemorrhagic telangiectasia resulting in constriction; the case also demonstrates the unusual but well-described complication of right-sided heart failure requiring extracorporeal membrane oxygenation (ECMO) support after pericardiectomy. CASE PRESENTATION: A previously healthy 48 year old man with a strong family history of Osler-Weber-Rendu disease presented to our institution with signs and symptoms of advance heart failure. His workup demonstrated a thickened pericardium and constrictive physiology. He was brought to the operating room where old clot and inflamed tissue were appreciated in the pericardial space and he underwent complete pericardiectomy under cardiopulmonary bypass. Separation from bypass, hampered by the development of right ventricular dysfunction and profound vasoplegia, required significant pressor and inotropic support. The right heart dysfunction and vasoplegia worsened in the early postoperative period requiring a week of ECMO after which his right ventricle recovered and he was successfully de-cannulated. CONCLUSION: Given the poor outcome of severe postoperative right ventricular failure after pericardiectomy, with high central venous pressure, a low gradient between central venous and pulmonary artery pressures and high vasopressor requirements, ECMO should be instituted promptly.

The heart transplant allocation change attenuates but does not eliminate blood group O waitlist outcome disadvantage.

BACKGROUND: Patients with blood group O have historically been disadvantaged in the United Network for Organ Sharing (UNOS) heart transplant allocation system. We sought to determine whether the new UNOS allocation system implemented in 2018 had an impact on waitlist and post-transplant outcomes among blood groups. METHODS: Using the UNOS database we included all adult patients listed and transplanted with first-time single-organ heart transplant between 10/17/15 and 10/1/21. For post-transplant outcomes, we separately evaluated all adult patients transplanted with the same time-frame. We used exclusion criteria and censoring to limit biases from changing clinical practices around the allocation change (10/18/2018), and from unequal or inadequate follow-up. We compared clinical characteristics and outcomes before and after the allocation change among each blood group. Fine-Gray and Cox regression models were used to estimate the effect of the new allocation system on competing waitlist outcomes- transplantation, death-or-removal from waitlist- and post-transplant survival, respectively. RESULTS: Of the 21,565 patients listed for transplantation 14,000 met criteria for waitlist analysis (7,035 in the old system vs. 6,965 in the new), and 7,657 met criteria for post-transplant analysis (3,519 in the old system vs. 4,138 in the new). Among each blood group, new allocation change was associated with higher transplantation rates lower waitlist days and lower waitlist mortality (except Group AB). However, despite improvements, Group O was still associated with worse waitlist outcomes for each metric compared to non-O Groups. The new allocation system did not have a significant impact on post-transplant survival among any blood groups. CONCLUSION: Changes in heart transplant allocation have attenuated but not eliminated blood group O disadvantage in access to donor hearts.

Center-Level Variation in Transplant Rates Following the Heart Allocation Policy Change.

IMPORTANCE: Wide state-level variability in waiting list outcomes have been noted for patients listed for heart transplant in the US, but little is known regarding center-level transplant rates since the heart allocation policy change. OBJECTIVE: To evaluate center-level transplant rates following the recent allocation policy change for heart transplant. DESIGN, SETTING, AND PARTICIPANTS: This cohort study used data from the United Network for Organ Sharing database from October 18, 2015, to March 1, 2020, for a nationwide analysis of transplant centers in the US. Transplant candidates were stratified into 2 time cohorts, with era 1 denoting the 3-year period before the policy change (October 18, 2018), and era 2 representing the 500-day period after the policy change but before the beginning of the COVID-19 pandemic. Data were analyzed from May to June 2021. EXPOSURE: The heart allocation policy change enacted on October 18, 2018. MAIN OUTCOMES AND MEASURES: Competing risk regression for waiting list outcomes was performed to calculate adjusted era 1 and era 2 center-level transplant rates. Rates were compared across regions and states, as well as within organ procurement organizations. Pearson correlation coefficient was used to assess center-level factors associated with era 2 transplant rates. RESULTS: Of 15 940 transplant candidates included for analysis, 5063 (median [IQR] age, 56 [45-63] years; 1385 women [27.4%]) comprised the era 2 cohort. The proportion of patients with temporary mechanical circulatory support increased between era 1 and era 2 (extracorporeal membrane oxygenation, 2.00% vs 3.42%; percutaneous ventricular assist device, 0.66% vs 1.86%; intra-aortic balloon pump, 5.21% vs 13.10%). The adjusted mean center-level likelihood of transplant increased after the rule change (from 48.1% in era 1 to 78.0% in era 2). Significant variation in transplant rates was observed across regions and states even among centers with shared organ procurement organizations. The largest absolute difference in transplant rates was 27.1% for 2 centers belonging to the same organ procurement organization. Centers with higher transplant volumes in era 2 and with a greater proportion of candidates with intra-aortic balloon pump were observed to have higher transplant rates. CONCLUSIONS AND RELEVANCE: Despite sharing organ supply and having a small geographical distance, these findings suggest that intercenter disparities in the likelihood of transplant have persisted following the heart allocation policy change. Further work is necessary to ensure equitable allocation of organs in heart transplant.

Experience, exposure, and attitudes regarding off-pump coronary artery bypass grafting techniques in US cardiothoracic surgical residents: Results of a survey.

Background: We sought to determine the current level of exposure to and interest in off-pump coronary artery bypass and beating heart surgery techniques regarding cardiothoracic surgical residents in the United States. Methods: An email survey consisting of 6 questions was sent to all cardiothoracic surgery residents of approved cardiothoracic training programs in the United States. The survey was emailed using the Qualtrics XM cloud-based survey platform. When the email responses were received, the answers to the survey questions were tabulated by the Qualtrics software and the resident's institution and year of graduation from their residency was noted. Results: Of 400 surveys sent, we received 99 responses for a response rate of 25%. A total of 78% of cardiothoracic surgery residents reported that they are at programs that do off-pump coronary artery bypass or beating heart surgery infrequently, noting that these cases are done in less than 5% of the coronary artery bypass graftings to which they are exposed. A total of 51% responded that they do not feel comfortable with off-pump coronary artery bypass grafting under any circumstances. A total of 49% reported some comfort with the technique with most of these respondents noting that they would do off-pump coronary artery bypass or beating heart surgery on a selective basis if the clinical situation arose and 4% plan to do off-pump coronary artery bypass routinely. Exposure to off-pump coronary artery bypass and beating heart surgery significantly correlated with future adoption of the technique by the cardiothoracic surgery residents. Cardiothoracic surgery residents in the lowest, middle, and highest terciles of exposure to off-pump coronary artery bypass and beating heart surgery plan to use these techniques 31%, 86%, and 75%, respectively, in selective cases when they are in independent practice. Conclusions: Over half of graduating cardiothoracic surgery residents do not feel comfortable with off-pump coronary artery bypass or beating heart surgery techniques. Exposure to these techniques in training correlates with comfort level and plans to use them in independent practice.

Impact of transplant center volume on donor heart offer utilization rates in the United States.

BACKGROUND: We tested the hypothesis that transplant centers (TCs) with higher volumes have higher donor heart (DH) offer utilization rates. METHODS: Using the Annual Data reports of the US Organ Procurement and Transplantation Network and the Scientific Registry of Transplant Recipients (SRTR) we reviewed all adult heart transplant offers between July 1, 2016 and June 29, 2019. Unadjusted donor offer utilization rates and observed to expected (O/E) DH utilization ratios adjusted using the SRTR model were calculated for each TC for all DH offers and for the following sub-categories: DH with left ventricular ejection fraction <60%, DH >40 years, DH >500 miles from TC, "hard-to-place hearts" (defined as those offered to >50 TCs) and DH designated as increased infectious risk. Univariable linear regression was used to identify a relationship between average yearly center volume and DH utilization. RESULTS: During the study 118,841 total offers were made to 107 TCs and 8300 transplants were performed. The unadjusted utilization rate was not associated with TC volume for all donor offers (p = .517). However, among all subcategories other than DH >40 years, the unadjusted DH utilization rate was associated with TC volume (p < .05). In addition, using the adjusted SRTR O/E ratio, there was a significant impact of TC volume on utilization rate for all donor offers (for an increase TC volume of 10 transplants/year coefficient = 0.095, 95% confidence interval: 0.037-0.151, p = .001). This relationship persisted with an identifiable change for each of the subcategories (p ≤ .001). CONCLUSIONS: TC volume is significantly correlated to DH offer utilization rate.

Impact of heart transplant allocation change on competing waitlist outcomes among listing strategies.

In 2018, the United Network for Organ Sharing (UNOS) adopted a 6-tier system for heart allocation which shifted patterns in listing strategies. The effects of the change on waitlist survival and transplantation rates have yet to be substantiated by analysis of competing outcomes among various listing strategies. This study included all adult patients listed for first-time heart transplantation in UNOS between 10/17/15 and 6/12/20. Clinical characteristics were compared before and after allocation change among various listing strategies: no support, inotropes, intra-aortic balloon pump, durable left ventricular assist device (LVAD), temporary VAD, and extracorporeal membrane oxygenation. Fine-Gray proportional subhazard models were used to estimate the effect of allocation change on competing waitlist outcomes-transplantation, death, or removal from waitlist-among each strategy. During the study period, there were 17 422 patients listed for heart transplantation. Among each listing strategy, clinical characteristics were similar before and after allocation change. Subhazard models demonstrated reduced risk for waitlist mortality (p < .001) among each strategy except temporary VAD and increased transplantation rates (p < .001) among each strategy except for durable LVAD. These results validate the association of the new allocation system on waitlist outcomes across listing strategies.

Early modified primary closure for treatment of cardiac implantable electronic device pocket infections.

BACKGROUND: Guidance for wound management of the vacated generator pocket in cardiac implantable electronic device (CIED) pocket infections after removal of all hardware and tissue debridement is limited. The typical surgical technique for management of a purulent wound is to allow healing by secondary intention. An alternative approach uses negative pressure wound therapy with or without delayed primary closure. While effective in managing infection, these approaches increase hospital length of stay and costs. We present our experience with a third option: modified early primary wound closure over a suction device. METHODS: All patients with CIED pocket infections who presented to our institution between September 2018 and October 2020 underwent extraction of hardware and modified primary wound closure over a negative pressure Jackson-Pratt drain. Length of hospital and postoperative stay, complications, and recurrent infections were recorded. RESULTS: During the study period, 14 patients underwent modified primary wound closure for CIED pocket infections. Mean length of hospital stay was 6.64 days ± 4.01 days (standard deviation [SD]). Mean postoperative length of stay was 3.92 ± 2.21 days (SD). Two patients (both on intravenous heparin for mechanical valve prostheses) required re-exploration for bleeding. No patients developed recurrent infection at a mean follow up of 363 ± 245 days (SD). CONCLUSION: Based on our experience, early modified primary wound closure for CIED pocket infections appears to be safe and allows for prompt discharge with no observed re-infections.

Likelihood of Aortic Valve Preservation During Repair of Acute Type A Aortic Dissection.

BACKGROUND: We sought risk factors for replacement of the aortic valve with or without the root (AVR/root) in the setting of acute type A aortic dissection (ATAD) repair. METHODS: All ATAD repairs at our institution from January 2005 to June 2018 were reviewed. Baseline characteristics were recorded. For patients with aortic valve preservation, we documented the degree of aortic insufficiency (AI) postoperatively and on subsequent echocardiograms when available. Logistic regression was used to determine the association between preoperative characteristics and the odds ratio of AVR/root. RESULTS: 206 patients underwent repair of ATAD. Thirty-four were excluded for no documented AI grading. Forty-six underwent AVR/root during repair of the ATAD (including 40 root replacements). Of 126 that did not undergo AVR/root, 42 (33.33%) had follow-up echocardiograms at a median of 68 months postoperatively, 2 required reintervention for valve insufficiency. An increase in the degree of AI, bicuspid valve morphology, size of the aortic root, and connective tissue disorder was significantly associated with increased risk of AVR/root. Of 130 patients without connective tissue disorder, bicuspid aortic valve, aortic root aneurysm or intimal root tear, the rate of valve preservation was 65/65 (100%), 25/29 (86.2%), and 22/40 (55%) for those presenting with mild, moderate, and severe AI, respectively. CONCLUSION: The degree of preoperative AI, bicuspid valve morphology, size of the aortic root, and connective tissue disorder significantly correlate with the failure of aortic valve preservation in patients with ATAD. The vast majority of tricuspid valves in patients without connective tissue disorder or aortic root pathology can be salvaged.

Likelihood of Aortic Valve Preservation During Repair of Acute Type A Aortic Dissection.

BACKGROUND: We sought risk factors for replacement of the aortic valve with or without the root (AVR/root) in the setting of acute type A aortic dissection (ATAD) repair. METHODS: All ATAD repairs at our institution from January 2005 to June 2018 were reviewed. Baseline characteristics were recorded. For patients with aortic valve preservation we documented the degree of aortic insufficiency (AI) postoperatively and on subsequent echocardiograms when available. Logistic regression was used to determine the association between preoperative characteristics and the odds ratio of AVR/root. RESULTS: A total of 206 patients underwent repair of ATAD. Thirty-four were excluded for no documented AI grading. Forty-six underwent AVR/root during repair of the ATAD (including 40 root replacements). Of 126 that did not undergo AVR/root, 42 (33.33%) had follow-up echocardiograms at a median of 68 months postoperatively and 2 required reintervention for valve insufficiency. Increase in degree of AI, bicuspid valve morphology, size of the aortic root, and connective tissue disorder were significantly associated with increased risk of AVR/root. Of 130 patients without connective tissue disorder, bicuspid aortic valve, aortic root aneurysm, or intimal root tear, the rate of valve preservation was 65/65 (100%), 25/29 (86.2%), and 22/40 (55%) for those presenting with mild, moderate, and severe AI, respectively. DISCUSSION: Degree of preoperative AI, bicuspid valve morphology, size of the aortic root, and connective tissue disorder significantly correlate with failure of aortic valve preservation in patients with ATAD. The vast majority of tricuspid valves in patients without connective tissue disorder or aortic root pathology can be salvaged.

Increased sensitivity to ischemic interval of donor hearts with diminished left ventricular function.

BACKGROUND: Previous studies have demonstrated that carefully selected donor hearts (DHs) with poor left ventricular ejection fraction (EF) may be transplanted with long-term survival equivalent to hearts with normal function. The purpose of this study is to facilitate their selection. METHODS: Using the United Network for Organ Sharing database, we reviewed all adult heart transplants between January 2000 and March 2016. Regression models were developed to estimate hazard ratios with 95% confidence intervals of post-transplant 1-year mortality and failure of EF to recover at 1 year for DHs with EF ≥50%, EF 40%-49.9%, and EF 30%-30.9%. RESULTS: During the study period, 31,979 DHs were transplanted. Compared with DHs with left ventricular ejection fraction ≥50%, DHs with reduced EF were younger and had slightly lower body mass index. There were no differences in the mechanism of death between groups and no differences in recipient characteristics, except for a higher incidence of African American recipients of hearts with an EF of 40%-49.9%. Of the variables analyzed, only a 1-hour increase in ischemia time had different hazard ratios for 1-year mortality between groups, with increasing hazard as EF diminished. It was also the only variable that predicted failure of recovery of normal EF and that was in the lowest EF group. CONCLUSIONS: The impact of DH traits associated with adverse outcomes after heart transplantation that we studied are similar between DHs with EF <50% and those with EF ≥50%. However, limiting ischemic time may be even more important for DHs with diminished left ventricular function, particularly at the low end of the EF spectrum.