Stulak, John M.

Background Diastolic dysfunction is common in patients with aortic stenosis and may influence outcomes following surgical aortic valve replacement. We aimed to examine the association of preoperative artificial intelligence (AI)‐generated diastolic function grades with early and late outcomes following aortic valve replacement and how postoperative progression influence prognosis. Methods We identified 5503 patients undergoing aortic valve replacement between 2000 and 2023. Diastolic function was assessed using a validated deep‐learning AI model applied to 12‐lead ECGs done preoperatively and on postoperative follow‐up. Diastolic grades were classified by AI into Grades 1 to 3. Longitudinal trend analyses and multivariable regression models were used to assess study end points. Results Among 5503 patients (mean age 72.4±10.8 years; 39% female), higher AI ECG diastolic grades were associated with greater comorbidity burden, including diabetes, renal disease, and heart failure. AI ECG diastolic Grade 3 was independently associated with higher in‐hospital mortality (odds ratio, 2.5; P =0.007) and other complications. At 5‐year follow‐up, patients with Grade 3 showed the least improvement in diastolic function by both ECG and echocardiography. Grades 2 and 3 diastolic function at baseline were independently associated with increased late mortality (hazard ratio, 1.3 and 2.45, respectively; both P <0.001). Additionally, lack of improvement in AI ECG diastolic grade by 1 year was also independently associated with late mortality. Conclusions AI ECG–derived diastolic function grades strongly correlates with early complications and long‐term mortality and diastolic progression after aortic valve replacement. AI ECG provides a powerful, noninvasive tool for risk stratification and longitudinal monitoring of patients with aortic stenosis.

We sought to characterize the long-term patency of various graft types in patients undergoing coronary artery bypass grafting. A comprehensive literature search identified 139 studies including 56,827 patients who underwent isolated coronary artery bypass grafting surgery. The mean patient age was 62 years (95% confidence interval: 60–63), and 80% (95% confidence interval: 79–82) were male. Patency outcomes were analyzed for each graft type, and parametric extrapolation was performed based on mean patency and mean follow-up time per conduit. The left internal mammary artery (LIMA) demonstrated the highest mean patency at 96% with a mean follow-up of 3.2 years, followed by the right internal mammary artery (RIMA) at 94% (2.8 years), gastroepiploic artery (GEA) at 93% (1.7 years), and radial artery (RA) at 89% (3.7 years). The saphenous vein graft had the lowest mean patency at 82% with a mean follow-up of 3.5 years. Extrapolated 20-year patency rates were 77% for LIMA, 64% for RIMA, 54% for RA, 42% for GEA, and 33% for saphenous vein graft. Arterial grafts demonstrated superior long-term patency compared to vein grafts. LIMA remains the primary conduit of choice, while RIMA, followed by RA and GEA, may be appropriate secondary arterial conduits depending on patient-specific factors. Vein grafts had the poorest long-term patency.

Abstract The expanding use of continuous‐flow left ventricular assist devices (CF‐LVADs) for end‐stage heart failure warrants familiarity with the physiologic interaction of the device with the native circulation. Contemporary devices utilize predominantly centrifugal flow and, to a lesser extent, axial flow rotors that vary with respect to their intrinsic flow characteristics. Flow can be manipulated with adjustments to preload and afterload as in the native heart, and ascertainment of the predicted effects is provided by differential pressure‐flow ( H ‐ Q ) curves or loops. Valvular heart disease, especially aortic regurgitation, may significantly affect adequacy of mechanical support. In contrast, atrioventricular and ventriculoventricular timing is of less certain significance. Although beneficial effects of device therapy are typically seen due to enhanced distal perfusion, unloading of the left ventricle and atrium, and amelioration of secondary pulmonary hypertension, negative effects of CF‐LVAD therapy on right ventricular filling and function, through right‐sided loading and septal interaction, can make optimization challenging. Additionally, a lack of pulsatile energy provided by CF‐LVAD therapy has physiologic consequences for end‐organ function and may be responsible for a series of adverse effects. Rheological effects of intravascular pumps, especially shear stress exposure, result in platelet activation and hemolysis, which may result in both thrombotic and hemorrhagic consequences. Development of novel solutions for untoward device‐circulatory interactions will facilitate hemodynamic support while mitigating adverse events. © 2021 American Physiological Society. Compr Physiol 12:1‐37, 2021.

ABSTRACT Background Addition of left heart catheterization (LHC) to exercise protocols allows for a unique focus on parameters of systolic and diastolic responses to increased activity in patients with left ventricular assist device (LVAD) support. Methods A retrospective review was conducted of all consecutive adult patients who underwent LHC with exercise for any indication from June 2017 to June 2023. For all patients, the relationship between exercise and parameters of LV systolic and diastolic response was assessed. Patients were divided into two cohorts based on the indication for testing: hemodynamic optimization (Optim, n = 5) or weaning consideration (Wean, n = 3). Results Eight patients (88% male, median age 57 years (IQR 44, 65)) were included. LVEF was 45% (IQR 45, 56) in Wean and 25% (IQR 20, 42) in Optim. LV systolic work index (LVSWI) increased more rapidly over levels of exercise in Wean vs. Optim (slope 46.3 vs. −0.625; p = 0.044) and LVSWI rose more quickly at lower levels of LV end diastolic pressure (LVEDP) in Wean vs. Optim (slope 219.5 vs. −2.008; p = 0.0026). Pulse power index was higher in Wean patients at baseline (0.046 (IQR 0.04, 0.07) vs. 0.016 (IQR 0.001, 0.04); p = 0.14) and peak exercise (0.12 (IQR 0.12, 0.12) vs. 0.06 (IQR 0.03, 0.1); p = 0.29). Conclusions Patients with favorable remodeling on LVAD support have significantly improved LV systolic and diastolic responses to exercise and a trend of higher systemic pulsatility. Improving our understanding of LV‐LVAD interactions with activity may aid in future efforts to improve exercise tolerance through speed modulation.

Abstract OBJECTIVES To estimate gender disparities among first and last authorships in cardiothoracic randomized controlled trials (RCTs) and association of gender with publications in high-impact journals. METHODS PubMed/MEDLINE database was searched from 1 January 2014 to 31 December 2020 using R statistical software via the ‘easyPubMed’ package to retrieve pertinent data. The ‘gender’ package was utilized to determine gender using the United States Social Security Administration Baby Name Data. The percentage of female first and last authors were computed along with determining the uniqueness of the names. The association of gender and publication in high-impact peer-reviewed journals was delineated. Jonckheere’s trend was computed. RESULTS The database search retrieved a total of 4820 RCTs, of which gender was encoded for the first author in 3247 (67%) RCTs, among which 911 (28%) studies had women as first authors, with a similar trend across 7 years (P = 0.23). Gender was encoded for the last author of 3204 (66%) RCTs, of which 622 (19%) studies had women as last authors, with a similar trend across 7 years (P = 0.45). A total of 627 studies were published in high-impact-factor journals, among which 79 (16%) studies had female first authors and 67 (13%) studies had female last authors. CONCLUSIONS There is an obvious gender disparity of first and last authors in cardiothoracic surgery-related RCTs, with a similar trend across 7 years. However, the post-hoc analysis did demonstrate a positive trend with an increase in the number of female first authors, demonstrating progress.

Cardiac fistulas present diagnostical and therapeutical challenges due to their variability in size, shape and pathway. Three-dimensional printing is increasingly used to provide a tactile representation that aids in preoperative planning and patient education. We present the case of a female in her 60s who developed a fistula between the left ventricle, right atrium and coronary sinus 2 years after bioprosthetic valve replacement. We used three-dimensional modelling to better understand her cardiac anatomy and optimise our surgical approach. She was discharged home without deficit following an uneventful postoperative course. Three-dimensional printing can improve patient care through tangible demonstration, preoperative planning and trainee education.

Introduction: Baseline hemodynamic parameters have been shown to predict postoperative outcomes such as right ventricular failure (RVF) in LVAD patients. The pressure adjusted heart rate (PaHR) is a hemodynamic parameter that has not been reported in LVAD recipients. Hypothesis: Patients with an elevated PaHR at baseline will have an increased risk of adverse outcomes following LVAD implantation. Methods: Historical cohort study of 273 patients with preoperative invasive hemodynamic assessment before durable LVAD implantation from January 1 st , 2007 to April 10 th 2017. Baseline patient characteristics and hemodynamic parameters were assessed. The primary endpoint was a composite of 30 day mortality, stage 3 acute kidney injury (AKI), and postoperative RVF. Univariate analysis was used to identify predictors of the composite endpoint, which were entered into stepwise backwards multivariate logistic regression to determine independent predictors of the composite outcome. Results: The mean age was 59 and 79% of the patients were male. The median INTERMACS profile was 4 and 166 (60%) of LVADs placed were as destination therapy. The primary composite endpoint was reached by 74 (27%) patient, including 30-day mortality in 13 (5%), severe AKI in 48 (18%) and RVF in 53 (19%). Univariate predictors of the composite endpoint (p <0.05) included atrial fibrillation, INTERMACS profile, home inotropes, preoperative IABP, admission creatinine, baseline Vasoactive-Inotropic Score, mean right atrial pressure (mRAP), mRAP/wedge, mean arterial pressure/mRAP, mean pulmonary artery pressure/mRAP, right ventricular stroke work index (RVSWi), pulmonary artery pulsatility index, and the PaHR. Logistic regression identified PaHR (OR 0.96, 95% CI 0.93-0.99, p=.026), RVSWi (OR 1.002, 95% CI 1.001-1.004, p=.002), home inotropes (OR 0.46, 95% CI 0.22-0.94, p=.034), atrial fibrillation (OR 0.48, 95% CI 0.26-0.88, p=.019) and admission creatinine (OR 0.51, 95% CI 0.34-0.77, p=0.002) as predictors of the composite endpoint. Conclusions: The PaHR is a readily available, novel hemodynamic parameter, that when elevated on baseline hemodynamic assessment can predict those patients at increased risk of postoperative adverse outcomes after durable LVAD implantation.

Introduction: Patients at increased risk of complications following LVAD placement are admitted to the hospital for hemodynamic optimization prior to LVAD implantation, which can include adjustment of medical therapy and/or placement of an IABP. Hypothesis: Prior to LVAD placement patients treated with an IABP during hemodynamic optimization will have similar outcomes despite worse baseline characteristics compared with patients treated medically. Methods: This single-center study included 199 non-inotrope dependent patients who underwent durable LVAD implantation between January 1 st , 2007 and April 10 th 2017. Hemodynamic data was collected retrospectively. Patients who received an IABP were compared to those who did not. Stage 2 or 3 acute kidney injury, right ventricular failure, and 30 day mortality was compared between patients with and without and IABP. Results: The mean age was 62.7 and 82.9% were male; 72 (36.2%) received an IABP. Baseline characteristics between groups were similar. Patients treated with an IABP had worse INTERMACS profiles and worse baseline hemodynamic parameters. The incidence of the primary composite endpoint was similar between patients who had an IABP and those who did not (23.6% vs 19.7%; p=0.517), as were each of the individual endpoints: stage 2 or 3 acute kidney injury (18.1% vs 14.2%; p=0.472), right ventricular failure (13.9% vs 13.4%; p=0.796), and 30 day mortality (6.9 % vs 3.2%; p=0.226). Patients treated with an IABP had greater relative reductions in mean right atrial pressure (-24.1% vs -5.9%; p=0.044), pulmonary artery systolic (-11.7% vs +3.3%; p=<0.001), diastolic (-17.0% vs +12.0%; p=0.015), and mean pressures (-15.2% vs 0.5%; p=<0.001). Conclusions: Despite worse hemodynamic parameters and INTERMACS profile at baseline, ambulatory heart failure patients who received an IABP prior to LVAD implantation did not have an increased incident of stage 2 or 3 acute kidney injury, right ventricular failure, or 30 day mortality, and had more favorable reductions in right atrial and pulmonary artery pressures. These results suggest that the use of the IABP prior to LVAD implantation in non-inotrope dependent patients with poor baseline hemodynamics may mitigate the risk of postoperative complications.

Introduction: Age ≥ 70 is used to exclude patients from cardiac transplantation. Elderly patients may be offered left ventricular assist device (LVAD) therapy as an alternative. It remains poorly defined how they respond to LVAD support. Hypothesis: Elderly patients have LVAD outcomes that are non-inferior to younger patients. Methods: Data on 1,149 continuous-flow LVAD recipients from May 2004 to May 2015 was pooled from the Mechanical Circulatory Support Research Network (MCSRN). Groups were assigned based on Age ≥ 70 (n = 163) and < 70 (n = 986). Results: Patients age ≥ 70 were more likely to be male (91%), have an ischemic cardiomyopathy (71%), atrial fibrillation (41%), hypertension (66%), diabetes (38%) and prior sternotomy (45%). Older patients also had a lower BMI and higher creatinine, 26.7 ± 0.4 v. 29.9 ± 0.5 and 1.46 ± 0.04 v. 1.35 ± 0.02, p < 0.05. The hazard ratio for mortality was highest in elderly patients in the early post-operative period and stabilized over time with no long-term differences in survival, p = 0.18, Figure 1a. Elderly patients had equivalent rates of device thrombosis and stroke, p = 0.47 and 0.44, Figures 1b-c. Survival free of gastrointestinal bleeding (GIB) at 1-year was 58% in elderly patients compared to 69% in younger patients, Figure 1d, p < 0.01. Multivariate cox regression revealed that age ≥ 70 was not a significant predictor of mortality (HR 0.93, 95% CI 0.69 - 1.25, p = 0.62), but pre-operative creatinine (HR 1.54, 95% CI 1.28 - 1.86, p < 0.01) and bilirubin (HR 1.2, 95% CI 1.03 - 1.4, p = 0.02) were. When age was considered a continuous variable, the HR was 1.2 (95% CI 1.07 - 1.3 per 10y, p < 0.01). Conclusions: Elderly patients, age ≥ 70, have equivalent long-term survival after LVAD implantation with similar rates of device thrombosis and stroke. Rates of GIB were higher in the elderly and this finding warrants caution when choosing anti-coagulation protocols in the elderly. Overall age ≥ 70 does not portend a poorer survival after LVAD implant.

Objectives: CABG and PCI are used for revascularization of multivessel coronary artery disease (MVCAD). However, limited information is available comparing the rates of in-hospital and 30-day major adverse cardiac and cerebrovascular event (early MACCE), including early death, stroke, myocardial infarction (MI), and repeat revascularization, among patients with multiple arterial CABG (MultArt) vs PCI. Methods: We reviewed 12,615 MVCAD patients with isolated primary CABG or PCI from 1993 through 2009. CABG patients (n=6,667) were grouped by number of arterial grafts into left internal mammary artery/saphenous vein (LIMA/SV) (n=5,712) or MultArt (n=955); PCI patients (n=5,948) into balloon angioplasty (BA) (n=1,020), bare metal stent (BMS) (n=3,242), and drug-eluting stent (DES) (n=1,686). Results: Early MACCE rate was significantly greater for PCI than CABG (8.5% vs 4.1% [P<.001]) and lower for MultArt than LIMA/SV or PCI (1.5% vs 4.5% and 8.5%, respectively [P<.001]). Stroke and early death rates were higher in CABG vs PCI (2.2% vs 0.4% [P<.001], and 1.5% vs 1.0% [P=0.01], respectively), whereas MI and repeat revascularization were lower (0.5% vs 6.0% and 0.3% vs 2.2%, respectively [P<.001]). Stroke and early death were similar in MultArt and PCI and lower vs LIMA/SV (0.6% and 0.4% vs 2.6%, and 0.5% and 1.0% vs 1.7%, respectively [P<.001]); MI and repeat revascularization rates were similar in MultArt and LIMA/SV and lower vs PCI (0.4% and 0.6% vs 6.0%, and 0.3% and 0.3% vs 2.3%, respectively [P<.001]). In propensity score-matched analysis, CABG had significantly improved early MACCE rate compared with BA (4.7% vs 13.2% [P<.001]), BMS (4.3% vs 8.3% [P<.001]), and DES (2.9% vs 5.5% [P=.008]), and MultArt compared with PCI (1.8% vs 7.8% [P<.001]) fig. Conclusions: In MVCAD patients undergoing isolated primary revascularization, CABG conferred lower early MACCE rate vs PCI. Early MACCE rate was markedly decreased after MultArt compared with LIMA/SV, BA, BMS, and DES.