Polyester Vascular Graft Material and Risk for Intracavitary Thoracic Vascular Graft Infection1.

Prosthetic vascular graft infections of the thoracic aorta are rare but can be fatal. Our comparison of collagen- and gelatin-coated grafts showed that collagen-coated grafts were associated with increased biofilm formation and bacterial adherence in vitro and with higher rates of perioperative vascular graft infections in vivo.

The role of FDG PET/CT in therapy control of aortic graft infection.

PURPOSE: 18F-FDG PET/CT (PET/CT) is a useful tool for the diagnosis of aortic graft infection (AGI), but has rarely been used to influence therapeutic decisions during follow-up. We aimed to study the role of PET/CT in the long-term monitoring of patients. METHODS: Participants of the prospective Vascular Graft Infection Cohort Study (VASGRA) were included if they had microbiologically proven AGI. We quantified the metabolic activity in PET/CT by using maximum standardized uptake value (SUVmax) and further classified it as being focal or diffuse. Multivariable linear regression models were fit using generalized estimating equations to investigate factors associated with SUVmax over time. RESULTS: Sixty-eight participants with AGI contributed to 266 PET/CTs including 36 examinations performed after stop of antimicrobial therapy. Higher C-reactive protein (CRP) (adjusted coefficient per log10 mg/L 0.05 [95% C.I. 0.02-0.08]) was associated with higher SUVmax. CRP, metabolic and clinical findings informed the decision to either start (medians of SUVmax 7.1 and CRP 31.5 mg/L; 100% focal uptake), escalate (SUVmax 9.5; CRP 31.5; 100% focal uptake), continue (SUVmax 6.0; CRP 9.95 mg/L; 90% focal uptake), or stop (SUVmax 4.3; CRP 3.5 mg/L; 61% focal uptake) antibiotic treatment. Of note, decisions to escalate or continue antibiotic treatment were taken despite normal CRP values in 12.5 and 35.7% of PET/CTs, respectively. CONCLUSIONS: Consecutive PET/CTs could influence the clinical decision-making in patients with AGI in the near future. More studies on the use of PET/CT in case of aortic graft infection may offer the potential for individualized treatment approaches. CLINICALTRIALS. GOV IDENTIFIER: NCT01821664.

Long-Term Outcomes after Minimally Invasive Aortic Valve Surgery through Right Anterior Minithoracotomy.

Background Minimally invasive aortic valve surgery (MIAV) through a right anterior minithoracotomy evolved to an accepted procedure with favorable short- and mid-term outcomes, whereas long-term results lack. The aim of this study was to evaluate the long-term outcomes. Materials and Methods All our MIAV patients were included (n = 225). Mean age was 68 ± 12 years, 29% were older than 75 years, and median EuroSCORE was 5 (0-11). Baseline characteristics, inhospital outcomes, and follow-up information about survival, major adverse cardiac and cerebrovascular events (MACCE), and need for reoperation were collected and analyzed. Results In this study, 30-day mortality was 1.3%, and there was no permanent stroke. Mean follow-up time was 69.65 ± 24 months, being the longest so far reported in the literature. At 1 and 7 years, survival was 95.8 and 79%, freedom from MACCE 98.1 and 95.7%, and from reoperation 99.5 and 98.7%, respectively. Conclusion MIAV is safe and feasible with favorable long-term outcomes. In the future, it could serve as benchmark for interventional methods as soon as indications are expanded to young and low-risk patients. Randomized studies are needed to compare the long-term outcomes of these approaches.

Effect of PEEP, blood volume, and inspiratory hold maneuvers on venous return.

According to Guyton's model of circulation, mean systemic filling pressure (MSFP), right atrial pressure (RAP), and resistance to venous return (RVR) determine venous return. MSFP has been estimated from inspiratory hold-induced changes in RAP and blood flow. We studied the effect of positive end-expiratory pressure (PEEP) and blood volume on venous return and MSFP in pigs. MSFP was measured by balloon occlusion of the right atrium (MSFPRAO), and the MSFP obtained via extrapolation of pressure-flow relationships with airway occlusion (MSFPinsp_hold) was extrapolated from RAP/pulmonary artery flow (QPA) relationships during inspiratory holds at PEEP 5 and 10 cmH2O, after bleeding, and in hypervolemia. MSFPRAO increased with PEEP [PEEP 5, 12.9 (SD 2.5) mmHg; PEEP 10, 14.0 (SD 2.6) mmHg, P = 0.002] without change in QPA [2.75 (SD 0.43) vs. 2.56 (SD 0.45) l/min, P = 0.094]. MSFPRAO decreased after bleeding and increased in hypervolemia [10.8 (SD 2.2) and 16.4 (SD 3.0) mmHg, respectively, P < 0.001], with parallel changes in QPA Neither PEEP nor volume state altered RVR (P = 0.489). MSFPinsp_hold overestimated MSFPRAO [16.5 (SD 5.8) vs. 13.6 (SD 3.2) mmHg, P = 0.001; mean difference 3.0 (SD 5.1) mmHg]. Inspiratory holds shifted the RAP/QPA relationship rightward in euvolemia because inferior vena cava flow (QIVC) recovered early after an inspiratory hold nadir. The QIVC nadir was lowest after bleeding [36% (SD 24%) of preinspiratory hold at 15 cmH2O inspiratory pressure], and the QIVC recovery was most complete at the lowest inspiratory pressures independent of volume state [range from 80% (SD 7%) after bleeding to 103% (SD 8%) at PEEP 10 cmH2O of QIVC before inspiratory hold]. The QIVC recovery thus defends venous return, possibly via hepatosplanchnic vascular waterfall.

Effects of Thoratec pulsatile ventricular assist device timing on the abdominal aortic wave intensity pattern.

Arterial waves are seen as possible independent mediators of cardiovascular risks, and the wave intensity analysis (WIA) has therefore been proposed as a method for patient selection for ventricular assist device (VAD) implantation. Interpreting measured wave intensity (WI) is challenging, and complexity is increased by the implantation of a VAD. The waves generated by the VAD interact with the waves generated by the native heart, and this interaction varies with changing VAD settings. Eight sheep were implanted with a pulsatile VAD (PVAD) through ventriculoaortic cannulation. The start of PVAD ejection was synchronized to the native R wave and delayed between 0 and 90% of the cardiac cycle in 10% steps or phase shifts (PS). Pressure and velocity signals were registered, with the use of a combined Doppler and pressure wire positioned in the abdominal aorta, and used to calculate the WI. Depending on the PS, different wave interference phenomena occurred. Maximum unloading of the left ventricle (LV) coincided with constructive interference and maximum blood flow pulsatility, and maximum loading of the LV coincided with destructive interference and minimum blood flow pulsatility. We believe that noninvasive WIA could potentially be used clinically to assess the mechanical load of the LV and to monitor the peripheral hemodynamics such as blood flow pulsatility and risk of intestinal bleeding.

Sex-related differences among patients undergoing surgical aortic valve replacement-a propensity score matched study.

OBJECTIVES: We investigated the sex-related difference in characteristics and 2-year outcomes after surgical aortic valve replacement (SAVR) by propensity-score matching (PSM). METHODS: Data from 2 prospective registries, the INSPIRIS RESILIA Durability Registry (INDURE) and IMPACT, were merged, resulting in a total of 933 patients: 735 males and 253 females undergoing first-time SAVR. The PSM was performed to assess the impact of sex on the SAVR outcomes, yielding 433 males and 243 females with comparable baseline characteristics. RESULTS: Females had a lower body mass index (median 27.1 vs 28.0 kg/m2; P = 0.008), fewer bicuspid valves (52% vs 59%; P = 0.036), higher EuroSCORE II (mean 2.3 vs 1.8%; P < 0.001) and Society of Thoracic Surgeons score (mean 1.6 vs 0.9%; P < 0.001), were more often in New York Heart Association functional class III/IV (47% vs 30%; P < 0.001) and angina Canadian Cardiovascular Society III/IV (8.2% vs 4.4%; P < 0.001), but had a lower rate of myocardial infarction (1.9% vs 5.2%; P = 0.028) compared to males. These differences vanished after PSM, except for the EuroSCORE II and Society of Thoracic Surgeons scores, which were still significantly higher in females. Furthermore, females required smaller valves (median diameter 23.0 vs 25.0 mm, P < 0.001). There were no differences in the length of hospital stay (median 8 days) or intensive care unit stay (median 24 vs 25 hours) between the 2 sexes. At 2 years, post-SAVR outcomes were comparable between males and females, even after PSM. CONCLUSIONS: Despite females presenting with a significantly higher surgical risk profile, 2-year outcomes following SAVR were comparable between males and females.

Mortality and neurologic injury after surgical repair with hypothermic circulatory arrest in acute and chronic proximal thoracic aortic pathology: effect of age on outcome.

BACKGROUND: The goal of this study was to determine whether advanced age affects mortality and incidence of neurological injury in patients undergoing surgical repair with hypothermic circulatory arrest in acute and chronic thoracic aortic pathology. METHODS AND RESULTS: A university center audit was done of 523 consecutive patients (median age, 64 years; interquartile range, 56-71 years) between 2005 and 2010. Mortality in acute type A aortic dissection (207 patients) was 9.7%, and in chronic ascending aortic aneurysms (316 patients) was 2.2% (P<0.001). Neurological injury was observed in 16.9% of patients with acute type A aortic dissection (chronic ascending aortic aneurysms, 7.9%; P=0.002). Multivariable regression analysis revealed hypothermic circulatory arrest >40 minutes (odds ratio [OR], 4.21; 95% confidence interval [CI], 1.60-11.06; P=0.004) and redo surgery (OR, 3.44; 95% CI, 1.11-10.64; P=0.03) but not age (OR, 1.98; 95% CI, 0.73-5.38; P=0.18) as independent predictor of mortality. Emergency surgery (OR, 3.27; 95% CI, 1.31-8.15; P=0.01) and extracardiac arteriopathy (OR, 2.38; 95% CI, 1.26-4.50; P=0.008) but not age (OR, 1.80; 95% CI, 0.93-3.48; P=0.08) were independent predictors of neurological injury. CONCLUSIONS: Age is not associated with increased risk for mortality and neurological injury in patients undergoing surgical repair for acute and chronic thoracic aortic pathology with hypothermic circulatory arrest. Extended hypothermic circulatory arrest times, reflecting the extent of disease, and redo surgery predict mortality, whereas emergency surgery and extracardiac arteriopathy predict neurological injury.

Effect of pulsatility on the mathematical modeling of rotary blood pumps.

In this study, the effect of time derivatives of flow rate and rotational speed was investigated on the mathematical modeling of a rotary blood pump (RBP). The basic model estimates the pressure head of the pump as a dependent variable using measured flow and speed as predictive variables. Performance of the model was evaluated by adding time derivative terms for flow and speed. First, to create a realistic working condition, the Levitronix CentriMag RBP was implanted in a sheep. All parameters from the model were physically measured and digitally acquired over a wide range of conditions, including pulsatile speed. Second, a statistical analysis of the different variables (flow, speed, and their time derivatives) based on multiple regression analysis was performed to determine the significant variables for pressure head estimation. Finally, different mathematical models were used to show the effect of time derivative terms on the performance of the models. In order to evaluate how well the estimated pressure head using different models fits the measured pressure head, root mean square error and correlation coefficient were used. The results indicate that inclusion of time derivatives of flow and speed can improve model accuracy, but only minimally.

Mitral valve repair with a device for artificial chordal implantation at 2 years.

Objectives: This study examines the early and midterm safety, efficacy, and durability of mitral valve repair for primary mitral regurgitation (MR) using the ChordArt device (CoreMedic) for chordal replacement. Methods: Five patients with symptomatic severe primary degenerative MR due to isolated central posterior leaflet prolapse/flail were treated with the ChordArt device in a transseptal surgical approach and followed prospectively with periodical clinical and echocardiographic assessments for 2 years. Results: Reduction of MR immediately after the implantation of artificial chords was achieved in all patients showing no or trace MR (<1+/4+). In all patients, MR <1+ was maintained during 24 months of follow-up. No dehiscence, detachment, or dislocation of the implanted ChordArt devices was observed. Transthoracic echocardiography showed that left ventricle end diastolic diameter significantly decreased during the whole follow-up period in comparison to baseline condition, especially at discharge and 1-month follow-up. Left ventricle end systolic diameter also significantly decreased during the whole follow-up period in comparison to baseline condition. Left atrial volume significantly decreased during the follow-up period in comparison to discharge. No major adverse events, as defined per protocol, were observed during the intervention or during the follow-up period. Conclusions: The ChordArt device allows successful treatment of primary degenerative MR due to posterior mitral leaflet prolapse or flail, with a good safety profile and promising immediate clinical and echocardiographic benefits that are confirmed up to 24 months.

Impact of pre-existing comorbidities on outcomes of patients undergoing surgical aortic valve replacement - rationale and design of the international IMPACT registry.

BACKGROUND: Degenerative aortic valve disease accounts for 10-20% of all cardiac surgical procedures. The impact of pre-existing comorbidities on the outcome of patients undergoing surgical aortic valve replacement (SAVR) needs further research. METHODS: The IMPACT registry is a non-interventional, prospective, open-label, multicenter, international registry with a follow-up of 5 years to assess the impact of pre-existing comorbidities of patients undergoing SAVR with the INSPIRIS RESILIA aortic valve on outcomes. IMPACT will be conducted across 25 sites in Austria, Germany, The Netherlands and Switzerland and intends to enroll approximately 500 patients. Patients will be included if they are at least 18 years of age and are scheduled to undergo SAVR with the INSPIRIS RESILIA Aortic Valve with or without concomitant ascending aortic root replacement and/or coronary bypass surgery. The primary objective is to determine all-cause mortality at 1, 3, and 5 years post SAVR. Secondary objectives include cardiac-related and valve-related mortality and structural valve deterioration including hemodynamics and durability, valve performance and further clinical outcomes in the overall study population and in specific patient subgroups characterized by the presence of chronic kidney disease, hypertension, metabolic syndrome and/or chronic inflammation. DISCUSSION: IMPACT is a prospective, multicenter European registry, which will provide much-needed data on the impact of pre-existing comorbidities on patient outcomes and prosthetic valve performance, and in particular the performance of the INSPIRIS RESILIA, in a real-world setting. The findings of this study may help to support and expand appropriate patient selection for treatment with bioprostheses. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT04053088 .

Automated Implantation of Artificial Mitral Chords: Preliminary Results From the Feasibility Trial.

PURPOSE: A novel chordal system enables automated implantation of artificial mitral chords to treat mitral regurgitation (MR). This article summarizes the first-in-man initial clinical results. DESCRIPTION: The CHAGALL (CHordArt system study for the treatment of mitral ReGurgitAtion due to leaflet proLapse or fLail) trial is a single arm, multicenter, prospective study to test the feasibility of this system for mitral repair. The interim clinical and echocardiographic results of the first 5 patients with a 12-month follow-up are presented. EVALUATION: Five patients (mean age, 64 years) with severe MR received implantation of neochords with this device under cardiopulmonary bypass. Technical success was obtained in all patients. Transesophageal echocardiogram showed either no or trace residual MR (<1+/4+) after repair. Survival at 30 days was 100%, and no device-related complication occurred. Reduction of MR was sustained up to 12 months. CONCLUSIONS: This novel chordal system is promising because it greatly facilitates the deployment of neochords to repair the mitral valve. Results at 12 months are encouraging. The device is currently under development for transcatheter approach.

Rivaroxaban in patients with mechanical heart valves: A pilot study.

BACKGROUND: Patients with mechanical heart valves are still not eligible for treatment with direct oral anticoagulants (DOAC). We aimed to conduct a proof-of-principle study investigating the anti-Xa inhibitor rivaroxaban as antithrombotic treatment in patients with recent mechanical aortic valve replacement. MATERIALS AND METHODS: Low-risk patients scheduled for elective mechanical aortic valve replacement were treated with rivaroxaban 20 mg once daily (OD) in a prospective cohort study, started on day 3 postoperatively and given for 6 months. The study was registered at ClinicalTrials.gov (#NCT02128841). RESULTS: Ten patients were included (median age, 48; range 39 to 60). Indication was aortic valve stenosis in 6 patients, aortic root aneurysm with severe aortic valve regurgitation in 3 patients, and mixed stenosis/regurgitation in 1 patient. Neither thromboembolic nor bleeding events were observed, and no patient died. Absence of valve thrombosis was demonstrated in all patients. On day 7, median D-dimers were 2723 µg/L (inter-quartile range [IQR] 1672, 5695 µg/L), median TAT levels were 4.5 µg/L (IQR 4.1, 5.6 µg/L); and median peak thrombin generation was 150 nM (IQR 91, 183). On day 90, median D-dimers were 426 µg/L (IQR 278, 569), median TAT levels were 2.7 µg/L (IQR 2.2, 3.1), and median peak thrombin generation were 66 nM (IQR 62, 87). CONCLUSIONS: Rivaroxaban 20 mg OD was safe and effective in a pilot study of 10 low risk patients with mechanical aortic heart valve. Our results justify larger studies investigating the application of anti-Xa inhibitors in patients with mechanical heart valves.

Outcome of video-assisted thoracoscopic implantation of epicardial left ventricular leads with visual targeting for cardiac resynchronization therapy.

OBJECTIVES: Our goal was to analyse the implantation and outcome of thoracoscopic epicardial leads after a failed endovascular approach or follow-up (FU) complications after endovascular implantation. METHODS: We reviewed the records of patients with failed endovascular left ventricular (LV) lead placement or complications during FU, who were subsequently referred to cardiac surgeons for treatment with thoracoscopic LV lead implantation. We analysed the reasons for endovascular failure; the indications for the surgical procedures; and the clinical, echocardiographic and device FU results. RESULTS: Between 2010 and 2013, a total of 23 patients were included. Among them, 17 of the patients had no previous cardiothoracic surgery, 13 (76%) had successful video-assisted thoracoscopy (VAT) LV lead implantation, 3 (18%) had a conversion to thoracotomy and 1 (6%) failed. Of the 6 patients with prior cardiothoracic surgery, 2 (33%) had VAT only, 3 (50%) had primary thoracotomies and 1 (17%) had a conversion. Two major complications occurred. The reasons for LV endovascular lead failure were subclavian vein occlusion (n = 2), implant failure (n = 13) and complications during the FU period (n = 8). FU information was available for 20 patients: 17 (85%) had improved symptoms. The median FU period was 33 months. A total of 78% of patients were in New York Heart Association (NYHA) functional class III-IV before the operation; 30% were in NYHA functional class III-IV at the last FU examination. The left ventricular ejection fraction increased from 25% before surgery to 31% at the last FU examination. Overall, sensing and pacing threshold values remained stable over time. In 1 patient, lead revision was necessary due to an increase in the pacing threshold. CONCLUSIONS: VAT implantation of LV leads had an excellent response rate with an improvement in NYHA functional class and left ventricular ejection fraction. The lead measurements were mainly stable over time.

Superior flow pattern of internal thoracic artery over saphenous vein grafts during OPCAB procedures.

BACKGROUND: The advantages of the use of the internal thoracic artery (ITA) over that of the saphenous vein (SV) for revascularization of the circumflex (Cx) or right coronary artery (RCA) are still debated. METHODS: Serial intraoperative flow measurements were carried out in 306 consecutive patients (mean age 64 years, mean Euroscore 5.1) undergoing off-pump coronary artery bypass grafting (OPCAB). The LAD was grafted in 302 patients [293 ITA (97%), 9 SV], the Cx in 252 patients [117 ITA (46%), 135 SV], and the RCA in 260 patients [36 ITA (14%), 224 SV]. RESULTS: Averages of 3.7+/-1.0 distal anastomoses/patient were constructed. Mean pulsatile index (PI) was significantly better for the single ITA/Cx-grafts (2.8+/-1.9, n=92) than for the single SV/Cx-grafts (3.3+/-1.7, n=43, p<0.05), whereas the mean flow did not differ (28+/-22 and 31+/-25 mL/min respectively, p=ns). Accordingly, the mean PI was significantly better for the single ITA/RCA-grafts (2.2+/-1.2, n=36) than for the single SV/RCA-grafts (3.4+/-2.6, n=178, p<0.01), whereas the mean flow did not differ (30+/-16 and 32+/-22 mL/min respectively, p=ns). The incidence of perioperative myocardial infarction tended to be lower in patients receiving an ITA to either the Cx or the RCA than in those receiving a SV, but the difference did not reach statistical significance [2/92 of ITA/Cx (2.2%) vs. 2/43 of SV/Cx (4.6%), 1/36 of ITA/RCA (2.8%) vs. 8/178 of SV/RCA (4.5%)]. CONCLUSION: The internal thoracic artery provides superior flow properties than the SV to the Cx and RCA regions with reduced perioperative ischemia. Whether this advantage persists after adjusting for the grade of the proximal coronary stenosis needs further studies.

Robotically Assisted Mitral Valve Repair as the Treatment of Choice for Patients with Difficult Anatomies.

Robotically assisted mitral valve repair has proven its efficacy during the last decade. The most suitable approach for patients with difficult anatomies, such as morbid obesity, sternal deformities, cardiac rotation, or vascular anomalies, represents a current challenge in cardiac surgery. Herein, we present the case of a 71-year-old patient affected by severe degenerative mitral valve regurgitation with pectus excavatum and a right aortic arch with an anomalous course of the left subclavian artery who was successfully treated using a Da Vinci-assisted approach.

Transcatheter or surgical repair for degenerative mitral regurgitation in elderly patients: A propensity-weighted analysis.

OBJECTIVE: To compare the outcomes of MitraClip and surgical mitral repair in low-intermediate risk elderly patients affected by degenerative mitral regurgitation (DMR). METHODS: We retrospectively selected patients aged ≥75 years, with Society of Thoracic Surgeons Predicted Risk Of Mortality (STS-PROM) <8%, submitted to MitraClip (n = 100) or isolated surgical repair (n = 206) for DMR at 2 centers between January 2005 and May 2017. To adjust for baseline imbalances, we used a propensity score model for average treatment effect on survival. RESULTS: After weighting, MitraClip showed fewer postoperative complications (P < .05) but increased residual mitral regurgitation (MR) ≥2 (27.0% vs 2.8%, P < .001) compared with surgery. One-year survival was greater after MitraClip compared with surgery (97.6% vs 95.3%, hazard ratio [HR], 0.09; confidence interval [CI], 0.02-0.37, P = .001), whereas 5-year survival was lower (34.5% vs 82.2% respectively, HR, 4.12; CI, 2.31-7.34, P < .001). Greater STS-PROM (HR, 1.18; CI, 1.12-1.24, P < .001) and MR ≥3+ recurrence (HR, 2.18; CI, 1.07-4.48, P = .033) were associated with reduced survival. 5-year MR ≥3+ was more frequent after MitraClip compared with surgery: 36.9% versus 3.9%, odds ratio, 11.4; CI, 4.40-29.68, P < .001. CONCLUSIONS: In elderly patients affected by DMR and STS-PROM <8%, the average effect of MitraClip resulted in lower acute postoperative complications and improved 1-year survival compared with surgery. However, MitraClip was associated with greater MR recurrence and reduced survival beyond 1 year. Long-term survival was impaired by patients' greater risk profile and MR recurrence. Early results are promising, but in the setting of operable patients with life expectancy beyond 1 year, the quality bar for transcatheter mitral repair needs to be raised.