Patient-specific tissue engineered vascular graft for aortic arch reconstruction.

Objectives: The complexity of aortic arch reconstruction due to diverse 3-dimensional geometrical abnormalities is a major challenge. This study introduces 3-dimensional printed tissue-engineered vascular grafts, which can fit patient-specific dimensions, optimize hemodynamics, exhibit antithrombotic and anti-infective properties, and accommodate growth. Methods: We procured cardiac magnetic resonance imaging with 4-dimensional flow for native porcine anatomy (n = 10), from which we designed tissue-engineered vascular grafts for the distal aortic arch, 4 weeks before surgery. An optimal shape of the curved vascular graft was designed using computer-aided design informed by computational fluid dynamics analysis. Grafts were manufactured and implanted into the distal aortic arch of porcine models, and postoperative cardiac magnetic resonance imaging data were collected. Pre- and postimplant hemodynamic data and histology were analyzed. Results: Postoperative magnetic resonance imaging of all pigs with 1:1 ratio of polycaprolactone and poly-L-lactide-co-ε-caprolactone demonstrated no specific dilatation or stenosis of the graft, revealing a positive growth trend in the graft area from the day after surgery to 3 months later, with maintaining a similar shape. The peak wall shear stress of the polycaprolactone/poly-L-lactide-co-ε-caprolactone graft portion did not change significantly between the day after surgery and 3 months later. Immunohistochemistry showed endothelization and smooth muscle layer formation without calcification of the polycaprolactone/poly-L-lactide-co-ε-caprolactone graft. Conclusions: Our patient-specific polycaprolactone/poly-L-lactide-co-ε-caprolactone tissue-engineered vascular grafts demonstrated optimal anatomical fit maintaining ideal hemodynamics and neotissue formation in a porcine model. This study provides a proof of concept of patient-specific tissue-engineered vascular grafts for aortic arch reconstruction.

Aortic arch shape after arch repair predicts exercise capacity: a multicentre analysis.

Aims: Coarctation of the aorta is associated with long-term morbidity including decreased exercise capacity, despite successful repair. In the absence of discrete recoarctation, the haemodynamic mechanism remains unknown. This multicentre study evaluated the relationship between aorta shape, flow, and exercise capacity in patients after arch repair, specifically through the lens of aortic size mismatch and descending aortic (DAo) flow and their association with exercise. Methods and results: Cardiac magnetic resonance, cardiopulmonary exercise test, and echocardiogram data within 1 year were analysed from 58 patients (age 28 ± 10 years, 48% male) across four centres with history of isolated arch repair. Aortic arch measurements were correlated with % predicted VO2max with subgroup analyses of those with residual arch obstruction, bicuspid aortic valve, and hypertension. Ascending aorta (AAo) to DAo diameter ratio (DAAo/DDAo) was negatively correlated with % predicted VO2max. %DAo flow positively correlated with VO2max. Sub-analyses demonstrated that the negative correlation of DAAo/DDAo with VO2max was maintained only in patients without arch obstruction and with a bicuspid aortic valve. Smaller aortic arch measurements were associated with both hypertension and exercise-induced hypertension. Conclusion: Aorta size mismatch, due to AAo dilation or small DAo, and associated decreased %DAo flow, correlated significantly with decreased exercise capacity after aortic arch repair. These correlations were stronger in patients without arch obstruction and with a bicuspid aortic valve. Aorta size mismatch and %DAo flow capture multiple mechanisms of altered haemodynamics beyond blood pressure gradient or discrete obstruction and can inform the definition of a successful repair.

Nighttime sleep and daytime sleepiness patterns among left ventricular assist device patients.

Despite the high prevalence of sleep disturbance in the heart failure population, information about its consequence on daytime function in patients with left-ventricular assist devices (LVADs) is limited. This study examined the nighttime and daytime sleep patterns and changes from pre-implant to 6 months post-implant. This study included 32 LVAD patients. Demographics, nighttime and daytime sleep variables were collected pre-implant and at 1, 3, and 6 months post-implant. Wrist actigraphy and self-report questionnaires measured objective and subjective sleep, respectively. Objective nighttime sleep data were sleep efficiency (SE), sleep latency (SL), total sleep time (TST), wake after sleep onset (WASO), and sleep fragmentation (SF). Objective daytime sleep data were nap times. Self-reported Subjective Sleep Quality Scale (SSQS) and Stanford Sleepiness Scale (SSS) were subjective measures. Increased SF and WASO scores and decreased TST and SE scores were found pre-LVAD implant, indicative of poor sleep quality. TST, SE, naptime and SSQS scores were higher at 3 and 6 months post-implant compared to baseline. Decreases in TST and SF scores were observed at 3 and 6 months post-implant along with increases in SSS scores. Increasing SSS scores and decreasing overall scores from pre- and up to 6 months post-implant suggest improvement in daytime function. This study provides information on sleep-daytime function in the LVAD patient population. Improvements in daytime sleepiness do not imply "good" sleep quality, consistent with the extant knowledge in LVAD literature. Future investigations should elucidate the mechanism by which sleep-daytime function influences quality of life.

Positive donor blood cultures are not associated with worse heart transplant survival.

BACKGROUND: Recent evidence has demonstrated that transplantation of hearts with blood culture positive donors (BCPDs) to pediatric recipients is safe and effective. Few studies have analyzed the effect of BCPD on adult heart transplant recipients. METHODS: The United Network for Organ Sharing (UNOS) database was retrospectively reviewed from September, 1987 to March, 2021. Exclusion criteria included pediatric donors/recipients, donor ejection fraction <10% or >85%, inactive listed recipients, donors missing blood cultures, and recipients missing follow-up time. Outcomes were compared with fully adjusted logistic models. To account for discrepancies in BCPD and non-BCPD covariates, an inverse proportionally weighted model with regression adjustment (IPWRA) was used. RESULTS: A total of 60 592 donors were non-BCPD, while 4009 were BCPD. 7% of hearts not transplanted were BCPD, while 6% of hearts transplanted were BCPD (p = .001). These rates have been nearly constant since 2005. There were no differences in short term survival between the two groups in the adjusted or IPWRA models (p = .103 and .277, respectively). Additionally, the BCPD group had longer ischemic time (3.24 vs. 3.06 h, p < .001), older donor age (32.73 vs. 31.65 years, p < .001), and older recipient age (52.76 vs. 52.09 years, p = .001). The IPWRA revealed an average additional 3.4 years of overall survival and 2.25 years of graft function for BCPD versus non-BCPD recipients, although these results failed to reach statistical significance (p = .387 and .527, respectively). CONCLUSIONS: Given the need for more donor hearts, donors with positive blood cultures should be considered. Great care in evaluating such patients is advised to eliminate donors with untreated infections, while carefully selected donors can be considered and used.

Figure of eight suture technique in aortic valve replacement decreases prosthesis-patient mismatch.

BACKGROUND: While the pledget suture technique has been the standard for surgical aortic. valve replacement (AVR), discussion continues regarding the possibility of the nonpledget suture technique to produce superior structural and hemodynamic parameters. This study aims to assess the effectiveness of the figure-of-eight suture technique in AVR, as determined by the incidence of prosthesis-patient mismatch (PPM). METHODS: We reviewed records of patients (N = 629) who underwent a surgical AVR procedure between January 2011 and July 2018 at a single institution. Indexed effective orifice area values and PPM incidence were calculated from implanted valve size and patient body surface area. Incidence of none, moderate, and severe PPM was compared across AVR suture techniques. RESULTS: A total of 570 pledget and 59 figure-of-eight patients were compared for incidence of PPM. Patients who received AVR with the pledget suture technique had significantly lower echocardiographic measurements of baseline ejection fraction than patients who had received AVR with the figure-of-eight suture technique (p = 0.003). Patients who received the figure-of eight suture had a 14% decrease in moderate PPM compared to patients who received the pledget suture (p = 0.022). Patients who received the figure-of-eight suture also had a significantly higher rate of no PPM (p = 0.044). CONCLUSIONS: The use of the figure-of-eight suture technique in AVR can reduce the incidence of moderate PPM. While the pledget suture is the standard technique in AVR, the figure-of-eight suture technique may offer better structural and hemodynamic outcomes, especially for patients with a smaller aortic annulus.

The prognostic role of advanced hemodynamic variables in patients with left ventricular assist devices.

BACKGROUND: Invasive hemodynamic variables obtained from right heart catheterization have been used for risk-stratifying patients with advanced heart failure (HF). However, there is a paucity of data on the prognostic value of invasive hemodynamic variables in patients with left ventricular assist devices (LVAD). We hypothesized that cardiac power output (CPO), cardiac power efficiency (CPE), and left ventricular stroke work index (LVSWI) can serve as prognostic markers in patients with LVADs. METHODS: Baseline hemodynamic data from patients who had LVAD ramp studies at our institution from 4/2014 to 7/2018 were prospectively collected, from which advanced hemodynamic variables (CPO, CPE, and LVSWI) were retrospectively analyzed. Univariate and multivariable analyses were performed for hemocompatibility-related adverse events (HRAE), HF admissions, and mortality. RESULTS: Ninety-one participants (age 61 ± 11 years, 34% women, 40% Black or African American, and 38% ischemic cardiomyopathy) were analyzed. Low CPE was significantly associated with mortality (HR 2.42, 95% CI 1.02-5.74, p = 0.045) in univariate analysis and Kaplan-Meier analysis (p = 0.04). Low LVSWI was significantly associated with mortality (HR 2.13, 95% CI 1.09-4.17, p = 0.03) in univariate analysis and Kaplan-Meier analysis (p = 0.02). CPO was not associated with mortality. CPO, CPE, and LVSWI were not associated with HRAE or HF admissions. CONCLUSIONS: Advanced hemodynamic variables can serve as prognostic indicators for patients with LVADs. Low CPE and LVSWI are prognostic for higher mortality, but no variables were associated with HF admissions or HRAEs.

Preserving the pulmonary valve in Tetralogy of Fallot repair: Reconsidering the indication for valve-sparing.

BACKGROUND: Tetralogy of Fallot (TOF) repair is a frequent procedure, and although valve-sparing (VS) repair is preferred, determining which patients can successfully undergo this operation remains controversial. We sought to identify parameters to determine a selective, accurate indication for VS repair. METHODS: We reviewed 71 patients (82%) undergoing VS repair. We analyzed hemodynamic data, intraoperative reports, and follow-up echocardiography results to identify acceptable indications. Patients requiring pulmonary valve (PV) reintervention versus no reintervention were compared. RESULTS: PV annulus size at repair was z-score of -2.0 (-5.3, 1.3). Approximately half (51%) had a z-score less than -2. Cox regression results showed this was not a risk factor for reintervention (p = .59). Overall, 1-, 3-, 5-, and 10-year freedom from PV reintervention rates were 95.8%, 92.8%, 91% and 77.8%, respectively. Residual pulmonary stenosis (PS) at initial repair was relatively higher in the reintervention group compared with no reintervention group (40 [28, 51] mmHg vs. 30 [22, 37] mmHg; p = .08). For patients with residual PS, pressure gradient (PG) was consistent over time across both groups (PV reintervention: -3 [-15, 8] mmHg vs. no reintervention: 0 [-9, 8] mmHg). The risk of PV reintervention is 3.7-fold higher when the PG from intraoperative TEE is greater than 45 mmHg (p = .04). CONCLUSIONS: Our review of the midterm outcomes of expanded indication for VS suggests intraoperative decision to convert to transannular patch is warranted if intraoperative postprocedure TEE PG is greater than 45 mmHg or RV pressure is higher than half of systemic pressure to prevent reintervention.

Ischemic time and patient outcomes after the 2018 UNOS donor heart allocation system change.

BACKGROUND: The allocation system for heart donors in the United States changed on October 18, 2018. The typical distance from donor hospitals to recipient hospitals has increased as has the ischemic time. We investigated patient outcomes with the new allocation system and the differential effects of ischemic time under both the old and new allocation schemas. METHODS: The United Network for Organ Sharing Registry (UNOS) was queried for data regarding heart transplants occurring from October 1, 1987 to March 1, 2021. In total, 62,301 adult heart transplants were examined. Survival outcomes at 30 days and 1 year and ischemic times were compared via adjusted logistic and Cox models (overall survival and time until post-transplant rejection). RESULTS: Mean ischemic time was slightly increased in the new system (3.43 h vs. 3.03 h, p < .001). Survival differences between old versus new systems were not observed in adjusted models (p = .818). However, there was evidence to suggest longer ischemic times are more detrimental to long-term survival under the new system (hazard ratio [HR] = 1.15 per hour increase; p = .001) versus the old system (HR = 1.08 per hour increase; p < .001), although this relationship did not reach statistical significance (p = .150). CONCLUSIONS: Although travel distances have significantly increased under the new allocation system, survival outcomes remain largely unchanged. Ischemic time is an influential factor in recipient survival that should be limited during organ transport. Further studies on the impact of travel distances and ischemic time under the new allocation system are needed.

Anomalous Origin of the Left Coronary Artery From the Right Pulmonary Artery of an Infant.

A female presented 2 weeks after birth with an unbalanced atrioventricular canal, double outlet right ventricle, mild pulmonary stenosis, and patent ductus arteriosus that eventually caused pulmonary over circulation. After pulmonary artery banding, she experienced myocardial ischemia, suggesting interference with coronary blood flow by the band that had been placed on the main pulmonary trunk. The band was removed and revised to bilateral branch pulmonary artery banding, and cardiac function improved. An anomalous left coronary artery from the underside of the right pulmonary artery was identified. Eight weeks later, the patient underwent coronary transfer and reimplantation of the left coronary artery into the aorta followed by main pulmonary artery banding. She subsequently underwent bidirectional Glenn.

Anemia and outcomes following left ventricular assist device implantation.

BACKGROUND: Patients with concomitant anemia and congestive heart failure have poor outcomes. The prevalence and clinical risk of anemia in patients receiving durable left ventricular assist devices (LVAD) remain unknown. METHODS: We retrospectively analyzed patients who underwent LVAD implantation between 2014 and 2018. The association between hemoglobin level at the time of index discharge and the one-year composite endpoint of heart failure readmissions or hemocompatibility-related adverse events was investigated. RESULTS: A total of 168 patients (57 [48, 66] years old, 123 males) were included and stratified into a classification of anemia (hemoglobin <9.7 g/dl, N = 99) or non-anemia (N = 69). The anemia group had a higher one-year incidence of the composite endpoint (56% vs 36%, p = .013) with an adjusted hazard ratio of 1.83 (95% confidence interval 1.08-2.82). Patients with anemia also experienced suboptimal bi-ventricular unloading. CONCLUSIONS: Anemia was prevalent in LVAD patients and associated with a greater risk of heart failure and hemocompatibility-related adverse events. The optimal threshold for therapeutic intervention in response to post-LVAD anemia needs further investigation.

Combined heart-liver-kidney transplant: The university of Chicago medicine experience.

BACKGROUND: Until recently, combined heart-liver-kidney transplantation was considered too complex or too high-risk an option for patients with end-stage heart failure who present with advanced liver and kidney failure as well. AIMS: The objective of this paper is to present our institution's best practices for successfully executing this highly challenging operation. At our institution, referral patterns are most often initiated through the cardiac team. RESULTS: Determinants of successful outcomes include diligent multidisciplinary patient selection, detailed perioperative planning, and choreographed care transition and coordination among all transplant teams. The surgery proceeds in three distinct phases with three different teams, linked seamlessly in planned handoffs. The selection and perioperative care are executed with determined collaboration of all of the invested care teams. CONCLUSIONS: Combined heart-liver-kidney transplantation can be successfully done by careful selection, coordination, and execution.

Social, economic and environmental implications of the COVID-19 pandemic.

The COVID-19 pandemic led to global lockdowns that severely curtailed economic activity. In this study, we set out to examine the social, economic, and environmental ramifications of the COVID-19 pandemic. This is a rare project that will have far-reaching consequences for the field. There are five sets of issues: short-term effects on oil and economic and agricultural policies, including regulations and COP26; long-term implications of monetary and fiscal intervention and investment in green agreements on future generations; prospects for further de-globalization and its effect on climate change and nature; and intergenerational environmental consequences, including debt and polling.

Hyperkalemia in Patients With Left Ventricular Assist Devices.

Background: Both hypo- and hyperkalemia are associated with adverse events in heart failure patients. Their effects on patients with left ventricular assist devices (LVADs) remains unknown. Methods and Results: The cohort included consecutive patients undergoing LVAD implantation between 2014 and 2018. In all, 170 patients (median age 56 years; 117 males) were stratified according to serum potassium levels 1 month after implantation into 3 groups: hypokalemia (<3.5 mEq/L; n=15), normokalemia (n=146), and hyperkalemia (>5.0 mEq/L; n=9). Compared with the normokalemia group, the adjusted hazard ratios for 1-year mortality were 0.91 (95% confidence interval [CI] 0.21-3.92) for hypokalemia and 4.14 (95% CI 1.47-11.65) for hyperkalemia. In the hyperkalemia group, the prevalence of renin-angiotensin-aldosterone system inhibitors decreased and serum potassium levels normalized following the first month. Conclusions: Hyperkalemia was associated with increased mortality during LVAD support. Management of serum potassium needs further investigation.

Pediatric aortic valve repair: Any development in the material for cusp extension valvuloplasty?

BACKGROUND: Aortic cusp extension is a technique for aortic valve (AV) repairs in pediatric patients. The choice of the material used in this procedure may influence the time before reoperation is required. We aimed to assess postoperative and long-term outcomes of patients receiving either pericardial or synthetic repairs. METHODS: We conducted a single-center, retrospective study of pediatric patients undergoing aortic cusp extension valvuloplasty (N = 38) with either autologous pericardium (n = 30) or CorMatrix (n = 8) between April 2009 and July 2016. Short- and long-term postoperative outcomes were compared between the two groups. Freedom from reoperation was compared using Kaplan-Meier analysis. Degree of aortic stenosis (AS) and aortic regurgitation (AR) were recorded at baseline, postoperatively, and at outpatient follow-up. RESULTS: At 5 years after repair, freedom from reoperation was significantly lower in the CorMatrix group (12.5%) compared to the pericardium group (62.5%) (p = .01). For the entire cohort, there was a statistically significant decrease in the peak trans-valvar gradient between preoperative and postoperative assessments with no significant change at outpatient follow-up. In the pericardium group, 28 (93%) had moderate to severe AR at baseline which improved to 11 (37%) postoperatively and increased to 21 (70%) at time of follow-up. In the biomaterial group, eight (100%) had moderate to severe AR which improved to three (38%) postoperatively and increased to seven (88%) at time of follow-up. CONCLUSION: In terms of durability, the traditional autologous pericardium may outperform the new CorMatrix for AV repairs using the cusp extension method.

A model for continued LVAD patient success: A 4-year readmission-free HeartMate 3 postoperative course.

Unplanned readmissions frequently occur following the implantation of a durable left ventricular assist device (LVAD) due to complications such as gastrointestinal bleeding and driveline infection. There is a paucity of literature describing the incidence of unplanned readmission in patients with a HeartMate 3 (HM3) Left Ventricular Assist System. In this report, we present the successful outcome of a patient with an HM3 LVAD who has experienced no unplanned readmissions in the 4-year post-implant phase. To our knowledge, this is the longest readmission-free case after HM3 implantation. A successful patient outcome was enabled by the use of the modular HM3 device, the postoperative prescription of beta-blockers and omega-3, the presence of strong social support, and open communication between the patient's caregivers and the LVAD team. Reducing the instance of unplanned readmission confers clinical benefits to the patient, as well as reducing the cost burden on the patient and the healthcare system.

An international survey: Tobacco smoking cessation strategies within left ventricular assist device centers.

BACKGROUND: Tobacco smoking is a significant source of morbidity in patients with a durable left ventricular assist device. While various cessation strategies have been investigated, the ability of ventricular assist device centers to implement a successful tobacco cessation program remains uncertain. We explored various cessation strategies employed by ventricular assist device centers and assessed perspectives of their effectiveness, as well as institutional investment in these programs. METHODS: A 37-question online self-report survey was created using Survey Monkey® and distributed worldwide. We investigated (1) programmatic strategies utilized for smoking cessation, (2) the respondent's perspective on the effectiveness of these strategies, (3) the structure with which these therapies are administered, and (4) overall organizational support for these treatments. RESULTS: A total of 47 centers worldwide completed the survey. The most common methods of tobacco cessation were pharmacologic and nicotine replacement therapy (78% and 66%). However, only about half (47% and 50%, respectively) of the centers indicated that these strategies were effective. When asked whether a respondent's center perceives that tobacco smoking should be a deciding factor in destination therapy evaluations, nearly a third (15, 32%) responded in the affirmative. CONCLUSION: While significant overlap exists among centers regarding treatments used for smoking cessation with left ventricular assist device patients, the most common treatments are not thought to be effective. While the current recommendations require tobacco smoking cessation in only bridge-to-transplant patients and not destination therapy patients, a number of centers disagree with the national guidelines and believe smoking should be prohibited in both populations.

Winter LVAD implantation is associated with adverse clinical outcomes.

BACKGROUND: The seasonal variation of incidence and severity of heart failure is well known. However, the impact of seasonal variation on clinical outcomes following left ventricular assist device (LVAD) implantation remains unknown. METHODS: We retrospectively reviewed consecutive patients who received LVAD implantation between January 2014 and December 2016 along with their first year of post-implant outcomes. Clinical outcomes were compared between those with winter LVAD implantation (between October and March) and those with non-winter LVAD implantation. RESULTS: 168 patients with a median age of 57 years and 130 males were included. There was no seasonal difference in the number of LVAD implantations. One-year survival free from major adverse events was significantly lower in the winter implant group (n = 88) compared to the non-winter group (n = 80) (44% vs 61%) with an adjusted hazard ratio of 1.81 (95% confidence interval 1.11-2.90, p = 0.014), largely due to a higher rate of heart failure readmission in the winter implant patients (incidence rate ratio 2.29, 95% confidence interval 0.89-5.84). CONCLUSION: Patients who underwent LVAD implantation during the winter season had a higher heart failure readmission rate. A detailed mechanism and therapeutic strategy given our findings warrant further investigation.

Impact of plasma volume status on mortality following left ventricular assist device implantation.

Worsening systemic congestion is often the central trigger of hospitalization in patients with heart failure. However, accurate assessment of congestion is challenging. The prognostic impact of systemic congestion following durable continuous-flow left ventricular assist device (LVAD) implantation remains unknown. Consecutive patients who received durable continuous-flow LVAD implantation between January 2014 and June 2017 and were followed for 1 year were included. The association of preoperative plasma volume status, which was calculated using patients' body weight and hematocrit and expressed as a deviation from ideal plasma volume, with 1-year mortality following LVAD implantation was investigated. In total, 186 patients (median 57 years and 138 males) were included. Baseline plasma volume status was -30.1% (-37.1%, -19.4%) on median. Eighty-eight patients (47%) had higher plasma volume status (>-29.8%), and their 1-year survival was significantly lower than those without (67% vs. 87%, P = .001). High plasma volume status was an independent predictor of 1-year death with an adjusted hazard ratio of 4.52 (95% confidence interval 1.52-13.5). Baseline systemic congestion, as defined by the high plasma volume status, was associated with higher mortality following durable continuous-flow LVAD implantation. The implication of improving preoperative plasma volume remains an area of needed investigation.

Perioperative improvement in serum albumin level in patients with left ventricular assist device.

BACKGROUND: The negative impact of baseline hypoalbuminemia on clinical outcome following left ventricular assist device (LVAD) implantation is well known. However, the implications of perioperative change in serum albumin levels on post-LVAD outcomes remain uninvestigated. METHODS: Among consecutive patients with baseline serum albumin <3.5 g/dl who received durable LVAD implantation between April 2014 and August 2017 and were followed for 1 year, the impact of perioperative change in serum albumin level from baseline to 3 months post-LVAD on the incidence of adverse events was investigated. RESULTS: Sixty-eight patients (median 60 years and 69% male) were included. Serum albumin change was an independent predictor of the occurrence of adverse events with an adjusted hazard ratio of 0.32 (95% confidence interval, 0.13-0.78) and a cutoff change of 0.7 g/dl. Those with albumin increase >0.7 g/dl had higher 1-year freedom from adverse events (45% vs. 14%, p = .008), dominantly due to lower incidence of death or sepsis compared with those without (p < .05 for both). CONCLUSION: Among those with baseline hypoalbuminemia, a considerable perioperative increase in serum albumin levels following LVAD implantation was associated with lower mortality and morbidity. The implication of aggressive nutrition intervention on LVAD patients is the next concern.