Building cardiac surgical programs in lower-middle income countries.

Objectives: Medical care in low-income countries is often limited by inadequate resources, treatment facilities, and the necessary infrastructure for healthcare delivery. We hypothesized that the development of an independently functioning, internationally supported Kenyan cardiac surgical training program could address these issues through targeted investment. Methods: A review was conducted of the programmatic structure and clinical outcomes from January 2008 to October 2021 at Tenwek Hospital, Bomet, Kenya. Program development phases included (1) cardiovascular care provided by 1 full-time US board-certified cardiothoracic surgeon; (2) short-term volunteer surgical teams from the United States and Canada; and (3) development of a cardiothoracic residency program based on the Society of Thoracic Surgeons training curriculum. Patient demographics and outcomes were analyzed throughout each phase of program development. Results: A total of 817 cardiac procedures were performed during the study period, including 236 congenital (28.8%) and 581 adult (71.1%) procedures. Endemic rheumatic valvular heart disease predominated (581 patients, 62.3%). Local surgical team case volume grew over the study period, overtaking visiting team volume in 2019. Perioperative mortality was 2.1% and consistent between the visiting teams and the locally trained teams. Surgical training via a 3-year cardiothoracic residency is now in its fourth year, with the 2 graduates now retained as full-time teaching staff. Conclusions: Global health partnerships have the potential to address unmet needs in cardiac care within low- and middle-income countries. These data support the concept that acceptable clinical outcomes and consistent growth in volume can be achieved during the transition toward fully independent cardiac surgical care.

Reduced Morbidity and Mortality Associated With Minimally Invasive Single-vessel Coronary Artery Bypass Compared With Conventional Sternotomy.

OBJECTIVE: We aimed to describe the safety and clinical benefits of minimally invasive, nonsternotomy coronary artery bypass grafting (MICABG) using data from The Society of Thoracic Surgeons (STS) National Database. BACKGROUND: MICABG has gained popularity, owing to expected lower perioperative morbidity and shorter recovery. Despite this, concerns remain regarding anastomotic quality and the validity of proposed perioperative benefits. METHODS: We queried the STS National Database for all patients who underwent single-vessel coronary artery bypass grafting (CABG) from January 2014 to December 2016 to compare outcomes of MICABG with conventional CABG. Patients who underwent concomitant or emergent procedures were excluded. Propensity-weighted cohorts were compared by operative approach with adjustment for variability across institutions. RESULTS: Of 12,406 eligible patients, 2688 (21.7%) underwent MICABG, and 9818 (78.3%) underwent conventional CABG. Propensity weighting produced excellent balance in patient characteristics, including completeness of revascularization, body mass index, and STS predictive risk scores. MICABG was associated with significant reduction of in-hospital mortality [odds ratio (OR)=0.32, absolute reduction (AR)=0.91%, P <0.0001]; 30-day mortality (OR=0.51, AR=0.88%, P =0.001), duration of ventilation (8.62 vs 12.6 hours, P <0.0001), prolonged hospitalization (OR=0.77, AR=1.6, P =0.043), deep wound infection (OR=0.33, AR=0.68, P <0.004), postoperative transfusions (OR=0.52, AR=7.7%, P <0.0001), and STS composite morbidity (OR=0.72, AR=1.19%, P =0.008). Subgroup analysis of only off-pump left internal mammary artery-left anterior descending CABG showed similar findings. Major adverse cardiac events and graft occlusion did not differ between groups. CONCLUSIONS: MICABG is associated with lower mortality and perioperative morbidity compared with conventional sternotomy CABG. MICABG may have a role in treating single-vessel disease.

Peripherally inserted concomitant surgical right and left ventricular support, the Propella, is associated with low rates of limb ischemia, with mortality comparable with peripheral venoarterial extracorporeal membrane oxygenation.

BACKGROUND: Mechanical circulatory support effectively treats adult cardiogenic shock. Whereas cardiogenic shock confers high mortality, acute limb ischemia is a known complication of mechanical circulatory support that confers significant morbidity. We compared our novel approach to peripheral mechanical circulatory support with a conventional femoral approach, with a focus on the incidence of acute limb ischemia. METHODS: This was a retrospective cohort study of patients treated with mechanical circulatory support between January 1, 2015 and December 5, 2021 at our institution. Patients receiving any femoral peripheral venoarterial extracorporeal membrane oxygenation were compared with those receiving minimally invasive, peripherally inserted, concomitant right and left ventricular assist devices. These included the Impella 5.0 (Abiomed, Danvers, MA) left ventricular assist device and the ProtekDuo (LivaNova, London, UK) right ventricular assist device used concomitantly (Propella) approach. The primary outcome was incidence of acute limb ischemia. The baseline patient characteristics, hemodynamic data, and post-mechanical circulatory support outcomes were collected. Fisher exact test and Wilcoxon rank sum test was used for the categorical and continuous variables, respectively. Kaplan-Meier curves and log-rank test were used to estimate overall survival probabilities and survival experience, respectively. RESULTS: Fifty patients were treated with mechanical circulatory support at our institution for cardiogenic shock, with 13 patients supported with the novel Propella strategy and 37 with peripheral venoarterial extracorporeal membrane oxygenation. The baseline characteristics, including patient organ function and medical comorbidities, were similar among the groups. Nine patients suffered mortality in ≤48 hours of mechanical circulatory support initiation and were excluded. Twenty patients (69%) suffered acute limb ischemia in the peripheral venoarterial extracorporeal membrane oxygenation group; 0 patients receiving Propella suffered acute limb ischemia (P < .001). The percentages of patients surviving to discharge in peripheral venoarterial extracorporeal membrane oxygenation and Propella groups were 24% and 69%, respectively (P = .007). CONCLUSION: Patients treated with the Propella experienced a lower incidence of acute limb ischemia compared with patients treated with peripheral venoarterial extracorporeal membrane oxygenation.

The effect of socioeconomic factors on patient outcomes in cardiac surgery.

OBJECTIVES: Healthcare delivery is heterogenous; the reasons for this are numerous and complex. Patient-specific factors including geography, income, insurance status, age, and gender have been shown to bias surgical outcomes. Utilizing a prospectively collected all-payer database, we aim to evaluate the influence of socioeconomic factors on mortality and length of stay (LOS) after common cardiac surgical procedures. METHODS: We utilized the National Inpatient Sample, Healthcare Cost and Utilization Project, Agency for Healthcare Research and Quality for the year 2019. We included patients undergoing coronary artery bypass grafting (CABG), aortic valve replacement (AVR), transcatheter aortic valve replacement (TAVR), and combined AVR/CABG using the 10th revision of the International Classification of Diseases procedure codes. AVR and CABG were combined into a separate cohort as this was felt to represent a different pathology than isolated valvular or coronary arterial disease. Baseline demographics were summarized. Multivariable regression was performed within each procedure group to model the odds of in-hospital mortality and hospital LOS with age, sex, insurance, zip-code median household income, and location as predictors. RESULTS: Baseline patient characteristics including gender, income, geography, and payer status were similar between CABG, AVR, and AVR/CABG. TAVR patients had a higher proportion of female sex and Medicare as the primary payer, with an overall greater age. Multivariable Cox proportional hazards regression found that higher income was strongly associated with decreased LOS following AVR and CABG, and moderately associated in TAVR and AVR/CABG. Private insurance was associated with a decreased LOS in patients undergoing CABG, AVR, TAVR, and AVR/CABG. Female sex and increased age were associated with increased odds of mortality in TAVR, CABG, and AVR/CABG. Private insurance was associated with a decreased odds of mortality in patients undergoing AVR. CONCLUSIONS: These findings reveal significant disparities in patient outcomes after routine cardiac operations that are associated with socioeconomic status. Patients who did not have private insurance or had lower incomes were found to be at risk for increased LOS. Women were at a higher risk of mortality for several operations, a finding which has been previously described elsewhere. Private insurance conveyed a decreased odds of mortality in patients undergoing AVR. This data set serves to highlight differences in healthcare outcomes based on a variety of socioeconomic, geographic, and other inherent factors. Additional research is needed to identify the mechanisms behind these disparities with the goal of providing equitable care to all patients.

Isolated left ventricular assist device implantation produces variable changes to patient body mass index.

BACKGROUND: Body mass index (BMI) is an important consideration for transplant-eligible left ventricular assist device (LVAD) recipients. LVAD therapy's impact on BMI is unclear. We evaluated BMI changes in patients who underwent LVAD implantation. The association between these patients' BMI and the transplant was studied. METHODS: This was a retrospective cohort study of patients who underwent LVAD implantation between January 1, 2012 and December 31, 2018 at our institution. Patients were stratified by preoperative BMI (kg/m2 ) into four groups: <30, 30-34.9, 34.9-39.9, and ≥40. BMI data were collected at 12 and 6 months prior to implantation, time of implantation, and 3- and 6- months postimplantation. RESULTS: A total of 107 patients underwent LVAD implantation at our institution. Data were available for 80 patients. Baseline characteristics included a mean age of 56.0 years, 69% male, and a mean implant BMI of 29.9 ± 6.8 kg/m2 . The mean BMI (kg/m2 ) for each of the BMI (kg/m2 ) groups <30, 30-34.9, 35-39.9, and ≥40 (n = 60, 25, 12, and 10, respectively) was 25.1, 32.5, 36.8, and 43.8, respectively. There was no consistent pattern with weight change across differing implant BMIs. No patient with a BMI of <30 gained sufficient weight to impact transplant candidacy. Twenty-three percent of patients with a BMI of 30-34.9 kg/m2 , 60% of patients with a BMI of 35-39.9 kg/m2 , and 87.5% of patients with a BMI of ≥40 kg/m2 had a 6-month BMI potentially affecting transplant. CONCLUSIONS: Associated weight changes during LVAD support may significantly impact transplant candidacy. Higher BMI groups may benefit from multimodal and multidisciplinary targeted weight-loss interventions.

How Does Multiple Listing Affect Lung Transplantation? A Retrospective Analysis.

The impact of multiple listing (ML) strategies on lung transplantation is unknown. Retrospective review of United Network for Organ Sharing (UNOS) registry for lung transplantation between May 1, 2005 and March 31, 2017 was performed. Characteristics of single (SL) and ML candidates were compared, and incidence density matching was used to select up to 10 controls for each case. Overall survival was evaluated using Cox regression stratified by matched sets. Nelson-Aalen estimators were used to estimate the cumulative incidence (CI) of transplant, death on the waiting list, and removal from wait-list as competing risks; Gray's test was used to compare wait list outcomes between groups. 23,445 subjects listed for lung transplant, of which 467 (2%) subjects listed at 2+ centers; 206 matched sets. There was no difference in overall survival of matched cases and controls at 1 year (ML 83.7%, SL 90.2%), 3 years (ML 63.9%, SL 68%), and 5 years (ML 51.9%, SL 49.3%) (p=0.24). The CIs of receiving a lung transplant at 2 years for ML and SL were 83.6% and 71%, respectively. Multi-listing increased the probability of receiving a transplant (p<0.001) but was not associated with waitlist mortality (p=0.13). There was no difference in post-transplant survival between ML and SL candidates (HR=0.82, p=0.32). ML was associated with a substantial increase in probability of lung transplantation, but there was no difference in overall survival, post-transplant, or wait-list mortality. Our study permits more informed decision-making for patients considering the ML strategy.

Acquired tracheomalacia due to aortic aneurysm managed with venopulmonary extracorporeal membrane oxygenation for perioperative support.

Extracorporeal membrane oxygenation (ECMO) has diverse applications. In the present report, we have described a case of tracheomalacia from a thoracic aortic aneurysm causing respiratory failure. Total arch replacement with reverse frozen elephant trunk grafting was performed. Perioperative ECMO support was accomplished with venopulmonary artery ECMO. This strategy allowed for preoperative oxygenation support, venous drainage during cardiopulmonary bypass, and postoperative support without cannula exchanges. Our patient required ECMO support for 12 days postoperatively. We have illustrated a unique case of acquired tracheomalacia but also an ECMO cannulation strategy allowing for preoperative oxygenation, seamless transition to cardiopulmonary bypass, and postoperative support.

Bleeding After LVAD Implant: If Things Do Not Add Up, Take a Look!

A 63-year-old male underwent re-exploration after HVAD implantation due to persistent postoperative bleeding. We present an unusual cause of postoperative bleeding after LVAD implantation for which early re-exploration and consideration of unusual etiologies is appropriate.

Seasonal trends in donor heart availability: an analysis of the UNOS database.

Despite the widespread belief that donor organ availability varies around holidays and seasons, there is little empirical data supporting this long-held belief. Variations in donor heart availability may be of interest to patients and clinicians. The UNOS/OPTN registry was queried for all heart donations from October 1987 through March 2017. Daily heart donation rates were modeled nationally using Poisson regression including splines for year and day of the year. Seasonality was assessed using a likelihood ratio test for the spine terms for day of the year. The holiday effect was assessed using conditional logistic regression. Seasonal plots suggest a significant, although modest, increase in organ availability during the summer months, except for region 1. The regions with the highest amplitude were region 7 (peak: June 21, amplitude: 16.63%) and region 6 (peak: July 5, amplitude: 11.29%). There was no significant difference in the odds of heart donation when comparing holidays vs. non-holidays using national data (odds ratio [95% CI]: 1.01 [0.98, 1.03], P = 0.560) or any regional subsets. There was no observable correlation between donor heart availability and holidays. However, a significant seasonality effect was observed with higher donation rates occurring during warmer months.

Temporary mechanical circulatory support prevents the occurrence of a low-output state in high-risk coronary artery bypass grafting: A case series.

BACKGROUND: Coronary artery bypass grafting (CABG) is a durable treatment for coronary artery disease. Left ventricular dysfunction (LVD) (a division of cardiothoracic surgery) (ejection fraction < 35%) significantly elevates perioperative risk for patients pursuing surgical revascularization. Periprocedural support with temporary mechanical circulatory support (tMCS) has shown benefit in this patient population. METHODS: Four patients with ischemic cardiomyopathy and LVD underwent CABG at our institution between 2017 and 2018. Each patient received perioperative ventricular support using a microaxial tMCS device (Impella 5.0®). The occurrence of a postoperative low-output state (LOS) was assessed for as well as postoperative morbidity and mortality, device-specific complications, and tMCS support duration. RESULTS: All patients survived to device explant without device-related complications. Two patients required reoperation for nondevice-related bleeding. All patients were without an LOS at 24 h postoperatively with cardiac indices of 2.9-3.6 L/min/m2 , normalized serum lactate, and vasoactive-inotrope scores of 0-12.0. There was a notably high incidence of acute renal failure (50%), which was observed in patients with preoperative cardiogenic shock. One patient died 10 days after the device explant. Of the three patients that survived to discharge, two were alive at the most recent follow-up. Postoperative device support varied widely (0-500 h). CONCLUSION: Perioperative tMCS may be a viable strategy for preventing postoperative LOS in high-risk CABG patients with a low complication rate and acceptable morbidity. The application of microaxial tMCS devices in CABG is an area that warrants further investigation to delineate its impact on perioperative outcomes and potentially expand the indications for such devices.

A Dual-Lumen Percutaneous Cannula for Managing Refractory Right Ventricular Failure.

A right ventricular assist device (RVAD) using a dual-lumen percutaneous cannula inserted through the right internal jugular vein (IJV) might improve weaning in patients with refractory right ventricular (RV) failure. However, the reported experience with this cannula is limited. We reviewed the records of all patients receiving RVAD support with this new dual-lumen cannula at our institution between April 2017 and February 2019. We recorded data on weaning, mortality, and device-specific complications. We compared outcomes among three subgroups based on the indications for RVAD support (postcardiotomy, cardiogenic shock, and primary respiratory failure) and against similar results in the literature. Mean (standard deviation [SD]) age of the 40 patients (29 men) was 53 (15.5) years. Indications for implantation were postcardiotomy support in 18 patients, cardiogenic shock in 12, and respiratory failure in 10. In all, 17 (94%) patients in the postcardiotomy group were weaned from RVAD support, five (42%) in the cardiogenic shock group, and seven (70%) in the respiratory failure group, overall higher than those reported in the literature (49% to 59%) for surgically placed RVADs. Whereas published in-hospital mortality rates range from 42% to 50% for surgically placed RVADs and from 41% to 50% for RVADs with percutaneous cannulas implanted through the right IJV, mortality was 11%, 58%, and 40% in our subgroups, respectively. There were no major device-related complications. This percutaneous dual-lumen cannula appears to be safe and effective for managing refractory RV failure, with improved weaning and mortality profile, and with limited device-specific adverse events.

Management of Coronary Artery Aneurysms at the Time of Surgical Revascularization.

BACKGROUND: Coronary artery aneurysms (CAAs) represent a rare pathology occurring in 1.5%-5% of routine coronary angiograms. Limited data exist on the management of CAA at the time of cardiac surgery. MATERIALS AND METHODS: A single-institution retrospective review was performed on 53 patients who underwent cardiac surgery in the setting of atherosclerotic CAA between 1993 and 2015. Patients were stratified based on treatment strategy: exclusion and distal bypass (n = 26) versus revascularization alone (n = 27). Comparisons were made with respect to mortality, need for further/concomitant interventions, and long-term cardiac function including myocardial infarctions and congestive heart failure. RESULTS: A total of 53 patients underwent cardiac surgery in the setting of CAA disease. Management strategies included ligation and bypass in 26 patients and distal bypass only in 27 patients (with four of the patients in this group undergoing coronary stenting across the aneurysm). There were no significant differences in patient demographics between the two groups. No significant difference was found in either 30-d (P = 0.74) or long-term mortality when exclusion of the CAA was performed compared with revascularization alone (P = 0.20). More exclusion procedures were performed earlier in the experience (median surgical date 2000), whereas revascularization alone predominated later in the experience (median surgical date 2007; P ≤ 0.001). CONCLUSIONS: The practice of CAA exclusion, while still performed in selected cases, has largely been supplanted in patients undergoing revascularization. Exclusion does not appear to offer any advantage over isolated revascularization, supporting the current trends in managing this rare condition.