Stefanos Demertzis

Background: Nonagenarians represent a cohort of patients at high or prohibitive risk in case of complex aortic procedures. A hybrid approach could reduce the surgical risk compared with a conventional surgery when performed at the age of 90. Case Summary: We reported the case of a 90-year-old man who presented with a progressive aortic arch dilatation due to a persistent type-1A endoleak following previous thoracic endovascular aortic repair due to type-B aortic dissection. The aortic computed tomography scan confirmed a 65x67mm aortic arch dilatation due to a type-1A endoleak and a transthoracic echocardiogram showed a severe aortic valve stenosis. On full sternotomy and partial cardiopulmonary bypass assistance, the patient underwent transcatheter aortic valve replacement combined with surgical brachiocephalic trunk and left common carotid artery debranching and thoracic endovascular aortic repair of the aortic arch. The postoperative course was uneventful and the patient was discharged home at postoperative day 15. Discussion: The described hybrid procedure lessened the prohibitive risks that could have been related to a conventional open aortic arch surgery in nonagenarians.

Background: The outcome of patients undergoing transcatheter aortic valve replacement (TAVR) can be affected by coexisting tricuspid regurgitation (TR). The aim of the study is to investigate the clinical results of patients undergoing TAVR with or without concomitant significant TR. Methods: Patients undergoing TAVR were divided into two groups according to TR severity: none/mild TR (low-grade) and moderate/severe TR (significant). Data were analysed and compared. Primary endpoint was the mortality 1-year. Secondary endpoints were re-hospitalization and the degree of postoperative and 1-year TR. Results: TAVR procedures were performed in 345 patients between September 2011 and February 2020. Median STS score was 4.3% (IQR: 2.6–7.2), median LVEF was 59.0% (IQR: 45.0–62.0), median aortic area was 0.70cm² (IQR: 0.60–0.86), median mean gradient was 43.0mmHg (IQR: 36.0–53.0). Before TAVR, 297 patients (86.1%) had low-grade TR and 48 (13.9%) significant TR. Mean age was 82.4 ± 5.7 and 83.8 ± 6.2 years in low-grade and significant TR group, respectively (p = 0.109), with 47.5% (low-grade TR) and 56.3% (significant TR) of female patients (p = 0.279). Patients showed differences in EuroSCORE-II (3.2% (IQR: 1.9–5.7) in low-grade TR vs. 5.6% (IQR: 3.7–8.1) in significant TR; p < 0.001), impaired right ventricular function (3.0% vs. 20.8%; p < 0.001) and pulmonary hypertension (9.1% vs. 39.6%; p < 0.001). Mean valve size was 27.7 ± 2.9 mm. Hospital mortality was 2.0% in low-grade TR and 4.2% in significantTR patients (p = 0.308). Among discharged patients (n = 337), seven patients died within 30 days (2.0% low-grade TR; 2.1% significant TR; logrank test p = 0.154) and 40 were re-hospitalized for heart failure (11.1% low-grade TR; 14.6% significant TR; p = 0.470). After one year, 26 patients died, corresponding to a mortality of 7.9 deaths per 100-person year (95% CI 5.2–12.0) in low-grade TR group and 9.1 deaths per 100-person year (95% CI 3.4–24.3) in significant TR group (logrank test p = 0.815), with HR (low grade vs. significant TR) of 0.87, 95% CI 0.26–2.89. Re-hospitalization for heart failure was 16.5% and 19.6% for low-grade and significant TR, respectively (p = 0.713). Echocardiographic and functional changes over time showed no significant interaction between TR and time. Conclusions: In our experience, patients undergoing TAVR showed similar 30-day and 1-year outcome and re-hospitalization rate, regardless of the degree of concomitant tricuspid regurgitation.

Introduction: Some evidence suggests that surgical minimally invasive (MIDCAB) and hybrid coronary revascularization (HCR) are safe and potentially effective at short-term follow-up. Data on long-term outcomes are more limited and inconclusive. Methods: Between February 2013 and December 2023, a total of 1997 patients underwent surgical coronary artery revascularization at our institution, of whom, 92 (4.7%) received left anterior mini-thoracotomy access (MIDCAB), either isolated (N = 78) or in combination with percutaneous coronary intervention (N = 14, HCR group). Results: After a median follow-up of 75 months (range 3.1: 149 months), cardiac mortality was 0% while overall mortality was 3%, with one in-hospital mortality and two additional late deaths. Conversion to sternotomy happened in two patients (2.1%), and surgical re-explorations occurred in five patients (4.6%), of whom three for bleeding and two for graft failure. All patients received left internal mammary (LIMA) to left anterior descending artery (LAD) grafting (100%). In the HCR group, 10 patients (72%) showed percutaneous revascularization (PCI) after MIDCAB, showing PCI on a mean of 1.6 ± 0.6 vessels and implanting 2.1 ± 0.9 drug-eluting stents. Conclusions: MIDCAB, in isolation or in association with hybrid coronary revascularization, is associated with encouraging short- and long-term results in selected patients discussed within a dedicated heart-team.

Background: The quality of a myocardial protection of a single-dose del Nido cardioplegia versus multiple dose blood-based cardioplegia on myocardial injury, outcomes and operative times in patients undergoing minimally invasive aortic valve replacement is basically unreported. Methods and Results: Preoperative and post-operative data, as well as technical details from isolated minimally invasive aortic valve replacements, performed using single-dose or multiple-dose cardioplegia were prospectively collected and retrospectively analysed. A total of 110 patients undergoing minimally invasive valve replacements at our institution composed two groups: 55 patients in the blood cardioplegia group (BloCa) and 55 in the del Nido group (DeNiCa). The two-matched groups were comparable in terms of preoperative variables. In the DeNiCa group, there was a statistically significant less need for cardiac defibrillation after aortic cross-clamp release ( p < 0.001). Moreover, the BloCa group received intraoperatively more blood transfusions ( p = 0.001) and more insulin administration for higher glucose levels ( p < 0.001). The BloCa group showed higher intraoperative lactate levels ( p = 0.01). Need for post-operative inotropic and vasoactive support, Creatine Kinase-MB levels after 6 and 12 h, onset of post-operative atrial fibrillation and length of stay were similar. No deaths occurred in neither groups. Conclusion: Single-dose del Nido cardioplegia in the setting of minimally invasive aortic surgery seems to offer adequate myocardial protection, comparable to multiple dose hematic cardioplegia. It has been documented a lower peri-operative need of defibrillation after cross-clamp release, lactate- and glucose peak values, as well as less blood transfusions compared to blood cardioplegic strategy.

Aims of the Study: We evaluated the clinical outcome and the hemodynamic and freedom from structural valve degeneration of two standard aortic bioprostheses. Methods: Clinical results, echocardiographic findings and follow-up data of patients operated for isolated or combined aortic valve replacement with the Perimount or the Trifecta bioprosthesis were prospectively collected, retrospectively analysed and compared. We weighted all the analyses by the inverse of the propensity of choosing either valves. Results: Between April 2015 and December 2019, 168 consecutive patients (all comers) underwent aortic valve replacement with Trifecta (n = 86) or Perimount (n = 82) bioprostheses. Mean age was 70.8 ± 8.6 and 68.8 ± 8.6 years for the Trifecta and Perimount groups, respectively (p = 0.120). Perimount patients presented a greater body mass index (27.6 ± 4.5 vs. 26.0 ± 4.2; p = 0.022), and 23% of them suffered from angina functional class 2–3 (23.2% vs. 5.8%; p = 0.002). Mean ejection fraction was 53.7 ± 11.9% (Trifecta) and 54.5 ± 10.4% (Perimount) (p = 0.994), with mean gradients of 40.4 ± 15.9 mmHg (Trifecta) and 42.3 ± 20.6 mmHg (Perimount) (p = 0.710). Mean EuroSCORE-II was 7 ± 11% and 6 ± 9% for the Trifecta and Perimount group, respectively (p = 0.553). Trifecta patients more often underwent isolated aortic valve replacement (45.3% vs. 26.8%; p = 0.016) and annulus enlargement (10.5% vs. 2.4%; p = 0.058). All-cause mortality at 30 days was 3.5% (Trifecta) and 8.5% (Perimount), (p = 0.203) while new pacemaker implantation (1.2% vs. 2.5%; p = 0.609) and stroke rate (1.2% vs. 2.5%; p = 0.609) were similar. Acute MACCE were observed in 5% (Trifecta) and 9% (Perimount) of patients with an unweighted OR of 2.22 (95%CI 0.64–7.66; p = 0.196) and a weighted OR of 1.10 (95%CI: 0.44–2.76, p = 0.836). Cumulative survival at 24 months was 98% (95%CI: 0.91–0.99) and 96% (95%CI: 0.85–0.99) for Trifecta and Perimount groups, respectively (log-rank test; p = 0.555). The 2-year freedom from MACCE was 94% (95%CI: 0.65–0.99) for Trifecta and 96% (95%CI: 0.86–0.99) for Perimount (log-rank test; p = 0.759, HR 1.46 (95%CI: 0.13–16.48)) in the unweighted analysis (not estimable in the weighted analysis). During the follow-up (median time: 384 vs. 593 days; p = 0.0001) there were no re-operations for structural valve degeneration. Mean valve gradient at discharge was lower for Trifecta across all valve sizes (7.9 ± 3.2 vs. 12.1 ± 4.7 mmHg; p < 0.001), but the difference did not persist during follow-up (8.2 ± 3.7 mmHg for Trifecta, 8.9 ± 3.6 mmHg for Perimount; p = 0.224); Conclusions: Postoperative outcome and mid-term follow-up were similar. An early better hemodynamic performance was detected for the Trifecta valve but did not persist over time. No difference in the reoperation rate for structural valve degeneration was found.

Objective: Transcatheter aortic valve replacement (TAVR) through alternative access routes is indicated in patients with severe aortic valve stenosis and diseased peripheral arteries. We analysed and compared the outcome of patients undergoing transapical (TA) and direct transaortic (TAO) TAVR procedures. Methods: Preoperative characteristics, procedural details, and thirty-day outcome of patients undergoing transapical (TA-TAVR group) and direct transaortic (TAO-TAVR group) TAVR procedures were prospectively collected and retrospectively analysed. Results: From March 2012 to March 2022, 81 TA and 82 TAO-TAVR (total: 163 cases) were performed with balloon-expanding (n = 120; 73.6%) and self-expandable (n = 43; 26.4%) valves. The mean age was 79.7 ± 6.2 and 81.9 ± 6.7 years for the TA- and TAO-TAVR groups, respectively (p = 0.032). Females were more represented in the TAO-TAVR group (56% vs. 32%; p = 0.003) while TA-TAVR patients showed a higher prevalence of previous vascular surgery (20% vs. 6%; p = 0.01), previous cardiac surgery (51% vs. 3.6%; p < 0.001), and porcelain aorta (22% vs. 5%; p = 0.001). The mean ejection fraction was 49.0 ± 14.6% (TA) and 53.5 ± 12.2% (TAO) (p = 0.035) while mean gradients were 35.6 ± 13.2 mmHg (TA) and 40.4 ± 16.1 mmHg (TAO) (p = 0.045). The median EuroSCORE-II was 5.0% (IQR: 3.0–11.0) and 3.9% (IQR: 2.5–5.4) for the TA- and TAO-TAVR groups, respectively (p = 0.005). The procedural time was shorter for TA procedures (97 min (IQR: 882–118) vs. 102 min (IQR: 88–129); p = 0.133). Mortality at day 30 was 6% in both groups (p = 1.000); the permanent pacemaker implantation rate was similar (8.6% vs. 9.7%; p = 1.000), and hospital stay was shorter for the TAO group (8 days (IQR: 6–11) vs. 10 days (IQR: 7–13); p = 0.025). Conclusions: Our results show that transapical and direct transaortic TAVR in high-risk patients with diseased peripheral arteries provide satisfactory clinical results with similar thirty-day outcomes.

Purpose: External cardiac assist devices are based on a promising and simple concept for treating heart failure, but they are surprisingly difficult to design. Thus, a structured approach combining experiments with computer-based optimization is essential. The latter provides the motivation for the work presented in this paper. Methods: We present a computational modeling framework for realistic representation of the heart’s tissue structure, electrophysiology and actuation. The passive heart tissue is described by a nonlinear anisotropic material law, considering fiber and sheetlet directions. For muscle contraction, an orthotropic active-strain model is employed, initiated by a periodically propagating electrical potential. The model allows for boundary conditions at the epicardium accounting for external assist devices, and it is coupled to a circulation network providing appropriate pressure boundary conditions inside the ventricles. Results: Simulated results from an unsupported healthy and a pathological heart model are presented and reproduce accurate deformations compared to phenomenological measurements. Moreover, cardiac output and ventricular pressure signals are in good agreement too. By investigating the impact of applying an exemplary external actuation to the pathological heart model, it shows that cardiac patches can restore a healthy blood flow. Conclusion: We demonstrate that the devised computational modeling framework is capable of predicting characteristic trends (e.g. apex shortening, wall thickening and apex twisting) of a healthy heart, and that it can be used to study pathological hearts and external activation thereof.

(1) Introduction: Intraoperative preservation solutions for saphenous vein grafts may influence the endothelial structure and increase the risk of graft failure after coronary surgery. The aim of the study was to compare the efficacy of three solutions in maintaining the endothelial cell integrity of venous segments. (2) Methods: We tested the efficacy of physiological saline solution (PSS), heparinized autologous blood (HAB) and DuraGraft^® in preserving the endothelium of vein segments by evaluating the degree of endothelial cell apoptosis. Two incubation times (2 and 4 h from harvesting) were used for each solution. The quantification of apoptotic cells was computed as the intensity nuclei/intensity area ratio. (3) Results: After 2 h of ischemia, the degree of apoptosis decreased progressively across the use of DuraGraft, HAB and PSS (p = 0.004), although only the difference between DuraGraft and PSS yielded a statistical significance (p = 0.002). After 4 h, a similar decrease in apoptosis was shown across the three media; however, statistical significance was not reached. The analysis of the elapsed time (2 or 4 h of incubation) showed that this was a relevant factor in maintaining the endothelial structural integrity independently from the storage solution (test for interaction of media and time p = 0.010). (4) Conclusion: Within 2 h of incubation, endothelial structural integrity depended on the incubating medium. DuraGraft better protected the SVG against ischemic-induced apoptosis when compared to saline solution. Prolonged ischemia was associated with extended endothelium damage and none of the studied solutions protected the vein graft.