Urgent Endovascular Aortic Repair Requiring Coverage of the Left Subclavian Artery.

BACKGROUND: Evaluation of the optimal left subclavian artery (LSA) management during thoracic endovascular aortic repair (TEVAR) involving the distal aortic arch in an urgent setting. METHODS: A total of 52 patients with acute aortic syndromes underwent TEVAR (March 2017 to May 2021) requiring proximal landing in the distal aortic arch. Decision for partial or complete LSA ostial endograft coverage, with or without additional bypassing, was made depending upon the aortic pathology and vascular anatomy. We focused on the patency of the circle of Willis and the unilateral dominance of one carotid or a vertebral artery: 35% underwent complete (complete LSA group) and 17% partial LSA coverage (partial LSA group), whereas in 48% the LSA was reached only by the bare springs of the endograft (control group). A total of 22% of the complete LSA group underwent LSA bypass before TEVAR, whereas 11% underwent cerebrospinal fluid drainage. Endpoints were 30-day and 1-year mortality, stroke, spinal cord ischemia (SCI), and malperfusion. RESULTS: Technical success was achieved in 96%. The endograft length was 171 ± 34 (complete LSA group) versus 151 ± 22 (partial LSA group) versus 181 ± 52 mm (control group), covering 6 ± 2 versus 5 ± 1 versus 7 ± 2 intercostal arteries. The 30-day mortality, stroke and SCI rates did not differ. One patient with arm malperfusion underwent LSA bypass post-TEVAR. After 1 year, aortic interventions occurred in 6 (complete LSA group) versus 22 (partial LSA group) versus 13% (control group). One-year mortality (0 vs. 0 vs. 8%), stroke (6 vs. 0 vs. 4%), and SCI (0 vs. 0 vs. 4%) were similar between groups. CONCLUSION: With an adequate analysis of vascular anatomy, coverage of the LSA for TEVAR is safe and may offer results similar to TEVAR starting distal to the LSA.

Five-Year Trends of Vascular Disease-Related Amputations in Romania: A Retrospective Database Study.

Background/Objectives: Lower extremity amputations (LEAs) are a burdensome complication of peripheral artery disease (PAD) and/or arterial embolism and thrombosis (AET). We assessed the trends in PAD- and/or AET-related LEAs in Romania. Methods: This retrospective study (2015-2019) analyzed data on minor and major LEAs in hospitalized patients recorded in the National School for Public Health, Management, and Health Education database. The absolute numbers and incidences of LEAs were analyzed by diagnosis type, year, age, sex, and amputation level. Results: Of 38,590 vascular disease-related amputations recorded nationwide, 36,162 were in PAD and 2428 in AET patients. The average LEA incidence in the general population was 34.73 (minimum: 31.96 in 2015; maximum: 36.57 in 2019). The average incidence of major amputations, amputations above the knee, hip amputations, amputations below the knee, and minor amputations was 16.21 (15.62 in 2015; 16.84 in 2018), 13.76 (13.33 in 2015; 14.28 in 2018), 0.29 (0.22 in 2017; 0.35 in 2019), 2.15 (2.00 in 2015; 2.28 in 2019), and 18.52 (16.34 in 2015; 20.12 in 2019), respectively. Yearly PAD- and/or AET-related amputations were significantly higher in men versus women. The overall number of LEAs increased with age, particularly in patients ≥ 70 years. The increase in the total number of amputations was mainly due to a constant rise in minor amputations for both groups, regardless of gender. Conclusions: PAD- and/or AET-related LEAs in Romania increased from 2015 to 2019, with men having a greater incidence than women. Raising awareness and effective management strategies are needed to prevent LEAs.

Annular rupture leading to fatal complications in an elderly patient with calcified aortic and mitral annulus undergoing transapical aortic valve implantation.

This case illustrates the awareness that must be taken of the high morphological risk due to the calcifications of both, the aortic and mitral annulus in elderly patients when performing transapical aortic valve implantation. In an 86-year-old, multimorbid woman (logistic EuroSCORE = 27%) with symptomatic aortic stenosis (annular diameter = 23.4 mm) and severe mitral annular calcification, the implantation of a 26-mm Edwards SAPIEN (Edwards Lifesciences, Irvine, California, United States) valve in aortic position was primary successful, with no paravalvular leakage, valve instability, or coronary malperfusion. Second, a persisting transmural bleeding led to hypovolemic shock, which could not be stabilized even after going on cardiopulmonary bypass, and the patient died in the operation room. The autopsy showed a subvalvular ventricular rupture due to a transmural perforation of the calcified fibrotic annulus during valvuloplasty.

Transapical minimally invasive aortic valve implantation and conventional aortic valve replacement in octogenarians.

OBJECTIVE: Transcatheter aortic valve implantation (TAVI) has been developed to minimize the operative trauma in high-risk patients. Patient selection for TAVI is still subject to debate and octogenarians are often regarded as high-risk patients. METHODS: In this single-center study, data of 169 octogenarians who received conventional AVR (90) or TAVI (79) have been analyzed retrospectively according to the endpoint definitions of the Valve Academic Research Consortium to answer the following questions: (a) Should patients due to their age of 80 years or older be considered as high risk? (b) Is the EuroSCORE a suitable tool for estimating mortality after AVR or TAVI in octogenarians? (c) Is TAVI the procedure of choice for octogenarians? RESULTS: TAVI patients showed higher comorbid conditions concerning an existing renal dysfunction (31 vs. 56%, p = 0.001), peripheral vascular disease (6 vs. 30%, p < 0.001), diabetes (19% vs. 49%, p < 0.001), a decreased ejection fraction (LVEF < 30%: 2 vs. 13%, p < 0.05), and pulmonary hypertension (23 vs. 48%; p < 0.005) with an increase of the perioperative risk represented by logistic EuroSCORE (AVR 11% ± 1.27 vs. TAVI 38% ± 1.35; p < 0.0005) and STS Score (7% ± 0.52 vs. 14% ± 0.56; p < 0.0005). All-cause and cardiovascular-cause in-hospital or 30-day mortality was 5.6% (n = 5) and 3.4% (n = 3) in the AVR cohort and 8.8% (n = 7) and 7.6% (n = 6) in TAVI-patients (p = 0.55; p = 0.31), respectively. The overall combined safety endpoint at 30 days was 22.2% (n = 20) in AVR patients and 29.1% (n = 23) with regard to the TAVI group (p = 38). Analysis of cerebrovascular complications, vascular complications, and pacemaker revealed no significant differences. In the AVR group, actuarial survival at 6 months and 1 and 2 years was 89, 78, and 74%, respectively. Data of the TAVI patients are only available for a follow-up of 6 months and revealed a survival of 85%. CONCLUSION: AVR and TAVI in octogenarians show comparable results, but the analyzed cohorts differ significantly in their risk profile. The results indicate an overrated perioperative mortality using the EuroSCORE but on the other hand logistic EuroSCORE represents articulately the different risk profile of the two groups. For this reason, we consider the EuroSCORE still to be a useful tool for preoperative risk assessment. Moreover, octogenarians cannot per se be considered as "true high risk" patients. Differentiated clinical judgment is most important for reasonable decision making.

Impact of preoperative statin therapy on adverse postoperative outcomes in patients undergoing cardiac surgery: a meta-analysis of over 30,000 patients.

AIMS: To determine the strength of evidence for preoperative statin use for prevention of adverse postoperative outcomes in patients undergoing cardiac surgery. METHODS AND RESULTS: After literature search in major databases, 19 studies were identified [three RCT (randomized prospective clinical trials), 16 observational] that reported outcomes of 31 725 cardiac surgery patients with (n = 17 201; 54%) or without (n = 14 524; 46%) preoperative statin therapy. Outcomes that were analysed included early all-cause mortality (30-day mortality), myocardial infarction (MI), atrial fibrillation (AF), stroke and renal failure. Odds ratio (OR) with 95% confidence intervals (95%CI) were reported using fixed or random effect models and publication bias was assessed. Preoperative statin therapy resulted in a 1.5% absolute risk reduction (2.2 vs. 3.7%; P < 0.0001) and 43% odds reduction for early all-cause mortality (OR 0.57; 95%CI: 0.49-0.67). A significant reduction (P < 0.01) in statin pretreated patients was also observed for AF (24.9 vs. 29.3%; OR 0.67, 95%CI: 0.51-0.88), stroke (2.1 vs. 2.9%, OR 0.74, 95%CI: 0.60-0.91), but not for MI (OR 1.11; 95%CI: 0.93-1.33) or renal failure (OR 0.78, 95%CI: 0.46-1.31). Funnel plot and Egger's regression analysis (P = 0.60) excluded relevant publication bias. CONCLUSION: Our meta-analysis provides evidence that preoperative statin therapy exerts substantial clinical benefit on early postoperative adverse outcomes in cardiac surgery patients, but underscores the need for RCT trials.

Cooling to 10 degrees C and treatment with Cyclosporine A improve cerebral recovery following prolonged hypothermic circulatory arrest in a chronic porcine model.

OBJECTIVE: This study was undertaken to assess whether cooling to 10 degrees C and/or treatment with Cyclosporine A (CsA) can reduce neurological injury during prolonged hypothermic circulatory arrest (HCA) in a chronic animal model. METHODS: In this blinded study, 24 pigs (20-23 kg) were randomized to HCA for 90 min at 20 degrees C (n=8), at 10 degrees C (n=8), or at 10 degrees C with 5 mg/kg CsA (n=8). CsA (or placebo) were given intravenously before and for 3 days after HCA. Hemodynamics and neurophysiological data were monitored periodically throughout the experiment and for 3 h after HCA, as well as intracranial pressure (ICP), which has been shown to correlate with outcome. Daily neurological/behavioral evaluation (mental status, coordination and appetite; 12=normal and 0=coma or death) was carried out until sacrifice on postoperative day (POD) 3. RESULTS: Overall survival rate was 83.3%: one 20 degrees C control, two 10 degrees C controls, and one 10 degrees C/CsA pig died and were replaced. Basic hemodynamic data revealed no significant differences between groups. ICP differed significantly among the groups during the first 3 h postoperatively (P=0.003 by repeated measures ANOVA); it was higher in the 20 degrees C group than in the 10 degrees C/CsA or 10 degrees C control groups. Recovery of visual evoked potentials was significantly better in the 10 degrees C/CsA group than in the 10 degrees C control group; no recovery was seen by 3 h in the 20 degrees C control group. Postoperative behavioral scores also differed significantly between the groups, P=0.03: a good behavioral outcome--a score >9 on POD3--was more prevalent among CsA-treated pigs (75%) than among 10 degrees C controls (50%), or 20 degrees C controls (12.5%, P=0.06). CONCLUSIONS: The data suggest that cooling to 10 degrees C and CsA treatment are both of benefit in improving cerebral recovery after HCA when compared with untreated 20 degrees C controls, and may be synergistic.

Spinal cord ischemia after selective cerebral perfusion in a porcine "frozen elephant trunk" simulation model.

BACKGROUND: The "frozen elephant trunk" procedure (FET) represents the therapy of choice for extended aortic diseases. The aim of our study was to analyze whether 90 minutes of selective cerebral perfusion (SCP) at 28 °C followed by permanent occlusion of the thoracic segmental arteries (TSA) would cause spinal cord ischemia in a porcine model. METHODS: 14 pigs (41 ± 3 kg) were cooled on CPB to 28 °C. After aortic clamping, SCP was established for 90 minutes. Randomly, in 7 animals the TSA were clipped (T4-T13); the TSA of 7 animals remained untouched. After the animals were weaned from CPB, hemodynamic data were registered for 120 minutes. Regional spinal cord blood flow (SCBF) was calculated, and motor-evoked potentials (MEP) were assessed at 6 time points. After sacrifice of the animals, the spinal cord was analyzed histologically by use of a schematic grading system (0 = normal; 8 = total necrosis). RESULTS: During SCP the SCBF was maintained at baseline (5.9 ± 2.4 mL/min/100 g) in the T4-T13 region but showed a decrease (from 8.4 ± 4.3 to 1.3 ± 1.5 mL/min/100 g) in the L1-L5 region. During reperfusion it increased, with two to three times higher values in the nonclipped animals. After 90 minutes of SCP, the MEP reached lower levels in the L1-L5 region of the TSA-clipped animals: 59% ± 7% vs 84 ± 15% (vastus medialis muscle) and 48% ± 6% vs 82% ± 26% (tibialis anterior muscle). The MEP recovered only in the nonclipped group. Higher ischemia rates were seen in the L1-L5 region of the TSA-clipped animals (score: 6.0 ± 0.6 vs 2.5 ± 2.3). CONCLUSIONS: 90 minutes of SCP provided sufficient spinal cord protection during arch replacement at 28 °C. In combination with permanent TSA occlusion, the lumbar spinal cord perfusion may be altered, which causes functional and structural damage.

Recent improvements in outcome with the Novacor left ventricular assist device.

BACKGROUND: The Novacor implantable, electrically powered, wearable, left ventricular assist device (LVAD) has been used as a bridge to transplantation at our institution since 1994. Recent changes in protocol have resulted in a decreased incidence of infections, thromboembolism, and mortality. METHODS: We reviewed the medical records of all 43 patients who received implantable LVADs at the Mount Sinai Medical Center. After 1998, a number of protocol modifications were instituted. Vascular grafts were changed from a low-porosity, woven polyester (Cooley) to a gelatin-sealed, knitted polyester graft (Vascutek), the devices were implanted pre-peritoneally rather than in the posterior rectus sheath, and extensive drainage of the chest and pre-peritoneal pocket was used. The following anti-coagulation regimen was used: low-molecular-weight Dextran for 1 day, initiated after chest tube drainage <50 cc/hour; then IV heparin for 10 to 14 days, beginning at 500 U/hour, slowly increasing partial thromboplastin time to 1.5 to 2 x control; and finally Coumadin, maintaining the international normalized ratio at 2.5 to 3.5. Daily aspirin, 325 mg, was begun on post-operative Day 7. We compared 22 patients who electively underwent surgery before the changes, Group I, with 18 patients treated thereafter, Group II. RESULTS: Groups I and II were well matched with regard to age (47 vs 44 years); cause of heart failure (idiopathic, 50% vs 44%; ischemic, 50% vs 56%), and duration of support (79 vs 76 days). The incidence of thromboembolic cerebrovascular events was significantly less in Group II (6%) than in Group I (23%), p = 0.025. The incidence of bleeding increased mildly in Group I. Pocket infections occurred in 27% of Group I patients vs 11% of Group II patients, p = 0.018. Only 2 patients (11%) in Group II died while receiving device support, vs 7 (32%) in Group I, p = 0.019. CONCLUSIONS: Our results indicate that pre-peritoneal implantation, use of a new generation of vascular grafts, extensive drainage, and a more restricted anti-coagulation regimen improve outcome after Novacor LVAD implantation for advanced heart failure.

Cerebral physiology and outcome after hypothermic circulatory arrest followed by selective cerebral perfusion.

BACKGROUND: This study explored the impact of an interval of hypothermic circulatory arrest (HCA) preceding selective cerebral perfusion (SCP) on cerebral physiology and outcome. This protocol allows use of SCP during aortic surgery without the threat of embolization inherent in balloon catheterization of often severely atherosclerotic cerebral vessels. METHODS: In this blinded study, 30 pigs (20 to 22 kg) were randomized after cooling to 20 degrees C. Pigs in the HCA-CPB group (n = 10) underwent 30 minutes of HCA followed by 60 minutes of total body perfusion (CPB); HCA-SCP pigs (n = 10) underwent 30 minutes of HCA followed by 60 minutes of SCP, and SCP pigs (n = 10) had 90 minutes of SCP without prior HCA. Fluorescent microspheres enabled calculation of cerebral blood flow during perfusion and recovery. Hemodynamics, intracranial pressure, cerebrovascular resistance, and cerebral oxygen consumption were also monitored. Daily behavioral scores were obtained for 7 days postoperatively. RESULTS: In all groups, cerebral oxygen consumption fell significantly with cooling (p < 0.0001), remained low during perfusion, and rebounded promptly with rewarming; cerebral oxygen consumption was significantly (p = 0.027) greater during SCP than during HCA-CPB. Cerebral blood flow was significantly higher throughout SCP in the HCA-SCP group (p < 0.0001) than with CPB. Cerebrovascular resistance during SCP and HCA-SCP was significantly lower (p = 0.036) than during CPB. Behavioral scores were significantly better with SCP than with HCA-CPB throughout recovery, but did not differ between SCP and HCA-SCP. CONCLUSIONS: This study suggests that a short period of HCA preceding SCP provides global cerebral protection comparable to continuous SCP, implying that in clinical practice, a short period of HCA to reduce risk of embolization will not compromise the superior cerebral protection provided by SCP.

Impact of hypothermic selective cerebral perfusion compared with hypothermic cardiopulmonary bypass on cerebral hemodynamics and metabolism.

OBJECTIVE: Hypothermic selective cerebral perfusion (SCP) is widely used for cerebral protection during aortic arch surgery, but the effect of the absence of systemic perfusion on cerebrovascular dynamics it has never been established. This study explored the physiology of prolonged SCP compared to hypothermic cardiopulmonary bypass (HCPB) in pigs. METHODS: In this blinded protocol, 29 juvenile pigs (20-23 kg) were randomized after cooling on cardiopulmonary bypass (CPB) to 20 degrees C. Group I pigs (n=14) underwent 90 min of SCP, while group II (HCPB, n=15) underwent total body perfusion. Fluorescent microspheres were injected during perfusion and recovery, enabling calculation of total and regional cerebral blood flow (CBF). Cerebrovascular resistance (CVR), oxygen consumption and intracranial pressure (ICP) were also monitored. RESULTS: CBF decreased significantly (P=0.0001) during cooling, but remained at significantly higher levels with SCP than with HCPB throughout perfusion and recovery (P<0.0001). CVR was significantly lower with SCP than with HCPB throughout perfusion (P=0.04). Oxygen consumption fell significantly with cooling (P=0.0001), remained low during perfusion, and rebounded promptly with rewarming; with SCP it was significantly higher than with HCPB throughout the perfusion interval (P=0.03), and remained higher thereafter. ICP rose significantly less with SCP than with HCPB (P=0.02). CONCLUSION: We conclude that, compared with HCPB, SCP results in beneficial cerebral vasodilatation, as evidenced by significantly higher CBF and oxygen consumption during SCP, by prompt recovery of oxygen consumption after rewarming, and by significantly lower ICP during perfusion and in the post-bypass period.

Evaluation of the use of lower body perfusion at 28°C in aortic arch surgery.

OBJECTIVES: Although hypothermic circulatory arrest (HCA) and selective cerebral perfusion (SCP) are widely used for cerebral protection during aortic arch surgery, these strategies offer no protection for mesenteric ischaemia during prolonged circulatory arrest. This study explored mesenteric haemodynamics, metabolism, oxidative stress and inflammatory response levels during isolated SCP and combined cerebral and lower body perfusion (CLBP) in pigs. METHODS: Fourteen pigs (35-45 kg) were cooled on CPB to 28°C. After 10 min of HCA, they were randomized to 60 min of isolated SCP (n = 7) and CLBP (n = 7) at low-flow pump rates: 10 ml/kg/min (SCP) and 20 ml/kg/min (LBP). Microspheres were injected at baseline, 5 and 60 min of SCP/CLBP and 5 and 60 min off CPB, to calculate mesenteric regional blood flow (RBF). Lactate levels and Oxy-DNA expression [fluorescence activated cell sorting (FACS)] in the portal venous blood were determined at the same time points. Semi-quantitative assessment of inflammatory cytokines was performed using real-time polymerase chain reaction (PCR) and immunhistochemical analyses. RESULTS: At baseline mesenteric, RBF was 61 ± 31 ml/min/100 g in the jejunum and 78 ± 43 ml/min/100 g in the colon. Whereas SCP provided a residual mesenteric RBF of 5%, CLBP offered 47% of the baseline jejunal (34 ± 10 ml/min/100 g) and 68% of the colonic RBF (52 ± 34 ml/min/100 g; P = 0.001). Lactate levels were significantly higher in then SCP group (15 ± 2 vs. 11 ± 3 mmol/l; P = 0.01). Oxy-DNA increased, reaching 137% of baseline (SCP) and 129% (CLBP) at 60 min SCP/CLBP, but recovered promptly during reperfusion. Real-time PCR revealed a massive increase in early cytokine expression vs. baseline, showing significant higher interleukin (IL) -6 (29 vs.2; P = 0.027) and COX-relative expression (7 vs. 3, P = 0.016) in the SCP group. Immunhistochemical analysis confirmed a higher immunological activity in the SCP group, showing more intensive signal for tumour necrosis factor-α, IL-6 and p38 when compared with the CLBP group. CONCLUSIONS: Low-flow CLBP provides a diminished but considerable mesenteric RBF, leading to lower lactate and oxidative stress levels and a diminished local inflammatory response reaction than isolated SCP.

Evaluation of risk factors for transient neurological dysfunction and adverse outcome after repair of acute type A aortic dissection in 122 consecutive patients.

OBJECTIVES: The aim of this retrospective study was to assess pre- and intraoperative factors leading to neurological complications and early death following repair of acute type A aortic dissection (ATAAD). METHODS: There were 122 patients (85 male, age: 58.6 ± 12.5 years) with ATAAD, treated consecutively from August 2003 to August 2010. Pre- and intraoperative variables were analysed using a logistic regression model in order to identify risk factors for temporary neurological dysfunction (TND) and adverse outcome (AO), defined as stroke and 30-day mortality. RESULTS: The 30-day mortality rate was 16.4%. Forty-one patients (33.6%) suffered transient neurological dysfunction and 20 (16.4%) had a postoperative stroke. Mean hypothermic circulatory arrest (HCA) temperature was 24 ± 4 °C. Selective cerebral perfusion (SCP) was performed in 99 (82%) patients, with a mean SCP flow rate of 10.3 ml/kg/min. The duration of lower body ischaemia (LBI) was 36 ± 27 min, of HCA 8.7 ± 15.5 min and of SCP 34 ± 28 min, respectively. Male gender [odds ratio (OR): 3.30, 95% confidence interval (CI): 1.15-9.47], diabetes (OR: 3.95, 95% CI: 1.18-13.24), compromised consciousness (OR: 6.65, 95% CI: 1.41-31.48) and manifest arterial atherosclerosis (OR: 6.68, 95% CI: 1.31-34.09) were detected as risk factors for TND, whereas a high body mass index (OR: 1.14, 95% CI: 1.01-1.3), a preoperative malperfusion syndrome (OR: 2.28, 95% CI: 0.84-6.18) and left ventricular ejection fraction <50% (OR: 3.84, 95% CI: 1.41-10.43) were detected as independent predictors for an AO. A dissection entry localized in the aortic arch or the descending aorta independently increased the risk for a postoperative stroke. A prolonged LBI increased the risk for AO (OR: 1.02, 95% CI: 1.00-1.04), whereas femoral cannulation showed a trend to an increased stroke incidence (OR: 4.2, 95% CI: 0.8-21.3). CONCLUSIONS: Regardless of standardized neuroprotective techniques, treatment of ATAAD remains a high-risk operation. Preoperatively, the presence of a reduced ejection fraction, a malperfusion syndrome or a high body mass index may increase the perioperative risk for an adverse outcome. A dissection 'entry' localized in the aortic arch or the descending aorta may increase the risk for postoperative stroke. Intraoperatively, cannulation of the femoral artery and extension of the LBI time over 45 min should be avoided. Especially in patients with manifest preoperative cerebral and/or end-organ malperfusion, the cannulation modality as well as the entire neuroprotective management should be chosen individually, respecting its limitations.

Impact of pump flow rate during selective cerebral perfusion on cerebral hemodynamics and metabolism.

BACKGROUND: Although hypothermic selective cerebral perfusion (SCP) is widely used for cerebral protection during aortic surgery, little is known about the ideal pump-flow management during this procedure. This study explored cerebral hemodynamics and metabolism at two different flow rates. METHODS: Fourteen pigs (33 to 38 kg) were cooled on cardiopulmonary bypass to 25°C. After 10 minutes of hypothermic circulatory arrest, the animals were randomly assigned to 60 minutes of SCP at two different pump flow rates: 8 mL·kg(-1)·min(-1) (n = 7) and 18 mL·kg(-1)·min(-1) (n = 7). Microspheres were injected at baseline, coolest temperature, and at 5, 15, 25, and 60 minutes of SCP to calculate cerebral blood flow, cerebral vascular resistance, metabolic rate, and intracranial pressure. RESULTS: Cerebral blood flow decreased during cooling to 41% of the baseline value (from 57 ± 10 to 23 ± 4 mL·min(-1)·100 g(-1)). It recovered during the initial 15 minutes of SCP, showing a significantly higher increase (p = 0.017) at high-flow versus low-flow perfusion (139 ± 41 versus 75 ± 22 mL·min(-1)·100 g(-1)). After 60 minutes of SCP the cerebral blood flow almost returned to baseline values in the low-flow group (43 ± 25 mL·min(-1)·100 g(-1)), but showed an unexpected decrease (30 ± 7 mL·min(-1)·100 g(-1)) in the high-flow group. The highest regional cerebral blood flow was seen in the cortex (66 ± 12 mL·min(-1)·100 g(-1)), followed by the cerebellum (63 ± 12 mL·min(-1)·100 g(-1)), the pons (51 ± 17 mL·min(-1)·100 g(-1)), and the hippocampus (36 ± 9 mL·min(-1)·100 g(-1)). Intracranial pressure increased from 11 ± 3 to 13 ± 5 mm Hg during cooling on cardiopulmonary bypass. During low-flow SCP, it stayed stable at baseline values, whereas high-flow perfusion resulted in significantly higher intracranial pressures (17 ± 3 mm Hg; p = 0.001). Changes in cerebral vascular resistance and metabolic rate showed no significant differences between the groups. CONCLUSIONS: High-flow SCP provides no benefit during long-term SCP at 25°C. Higher cerebral blood flow during the initial SCP period leads to cerebral edema, with no profit in metabolic rate.

Transapical valve implantation after David operation and stenting of the descending aorta.

This case report illustrates our experience with transapical minimally invasive aortic valve implantation in a patient with an extended aneurysm of the thoracoabdominal aorta, who had previously undergone a replacement of the ascending aorta with concomitant aortic valve reconstruction (David procedure). Endovascular stent grafting of the descending aorta was also performed. The implantation of a 23-mm SAPIEN valve (Edwards Lifesciences, Irvine, CA) did not interfere with the existing 26-mm aortic Hemashield prosthesis (Boston Scientific, Natick, MA) or the previously implanted endograft in the descending aortic position. No paravalvular leakage with aortic valve regurgitation, prosthesis instability, or coronary malperfusion was seen after valve implementation.

Effect of pressure management during hypothermic selective cerebral perfusion on cerebral hemodynamics and metabolism in pigs.

OBJECTIVE: The effect of perfusion pressure on cerebral hemodynamics and metabolism during selective cerebral perfusion in patients undergoing aortic surgery is still unknown. This study explored cerebral blood flow, metabolic rate, and intracranial pressure at different pressure rates. METHODS: Twenty-five pigs (32-38 kg) were cooled during cardiopulmonary bypass to 25 degrees C. After 10 minutes of hypothermic circulatory arrest, the animals were randomized to 60 minutes of selective cerebral perfusion at 3 different perfusion pressures: group I (n = 8), 40 mm Hg; group II (n = 9), 60 mm Hg; and group III (n = 8), 80 mm Hg. Microspheres were injected at baseline, the coolest temperature, and 5, 15, 25, and 60 minutes of selective cerebral perfusion, respectively, to calculate cerebral hemodynamics. RESULTS: Cerebral blood flow decreased during cooling to 54% of baseline value (50 mL/min per 100 g) and recovered in all groups during the first 15 minutes of selective cerebral perfusion. In groups I and II it reached 110% to 113% of baseline values, whereas group III animals showed significantly higher values (P(25min) = .003) during the first 25 minutes of selective cerebral perfusion (360%; 153 mL/min per 100 g). Cerebral blood flow decreased in all groups over the following 35 minutes of selective cerebral perfusion to 57% of baseline value. Cooling to 25 degrees C decreased the intracranial pressure to 10 mm Hg (93%). During selective cerebral perfusion, groups I and II showed a further intracranial pressure decrease to 45% and 82%, respectively, whereas group III, with 15 mm Hg (128%), had significantly higher intracranial pressure values at the end of selective cerebral perfusion (P(25min) = .03 and P(60min) = .02). The metabolic rate decreased to 30% of the baseline value during cooling, reaching 34% to 38% after 60 minutes of selective cerebral perfusion, with no significant differences between groups. CONCLUSION: High-pressure perfusion provides no benefit during long-term selective cerebral perfusion at 25 degrees C. Higher cerebral blood flow during the initial 25 minutes of selective cerebral perfusion leads to cerebral edema, with no alteration in metabolic rate.

Minimally invasive transapical aortic valve implantation and the risk of acute kidney injury.

BACKGROUND: The new technique of minimally invasive transapical aortic valve implantation (TAP-AVI) deals with high-risk patients and despite the absence of cardiopulmonary bypass it might lead to renal impairment. The aim of this study was to estimate the risk of the development of acute kidney injury (AKI) after TAP-AVI and to identify possible risk factors with regard to the morbidity and mortality of the patients. METHODS: Data of 30 consecutive patients undergoing TAP-AVI were recorded and followed up for 8 weeks. Postoperative AKI has been defined according to RIFLE criteria. Two patients on chronic hemodialysis have been followed up. RESULTS: Of 28 patients, AKI occurred in 16 patients (57%). Statistical analysis revealed no influence on the risk of developing AKI caused by the dose of applicated contrast medium (p = 0.09), the patient's age (p = 0.5), or the existence of diabetes (p = 0. 16). Analysis concerning the relationship between a preexisting coronary heart disease and AKI showed a tendency to be associated with a higher risk of the development of AKI (70% preexisting congenital heart disease in the AKI group versus 50%; p = 0.28). Only a preoperative serum creatinine greater than 1.1 mg/dL was a strong predictor for developing AKI (p < 0.01). Length of stay in the intensive care unit and the complete length of hospital stay revealed no difference with regard to postoperative development of AKI though statistical analysis showed a trend to a higher mortality in the AKI group (27% vs 6%); univariate analysis did not reach statistical significance (p = 0.13). CONCLUSIONS: The TAP-AVI seems to be a feasible procedure for high-risk patients with a clear risk of developing AKI. Patients at risk should be identified and, if indicated, already preoperatively treated in collaboration with the attending nephrologists.

Statins improve surgical ablation outcomes for atrial fibrillation in patients undergoing concomitant cardiac surgery.

Ablation outcomes were investigated in patients with and without statin pretreatment before cardiac surgery with concomitant surgical ablation for atrial fibrillation (AF). A prospective cohort study was performed containing 149 patients (n=73 statin group vs. n=76 control group) undergoing on-pump cardiac procedures with surgical ablation for paroxysmal or persistent AF. Measured outcomes were freedom from AF in the intensive care unit, discharge and at three and six months follow-up and perioperative markers of inflammation (white blood cell count, C-reactive protein). Independent predictors for freedom from AF were assessed. Groups did not differ with respect to EuroSCORE, New York Heart Association class, left atrial size, anti-arrhythmic drug therapy or aortic cross-clamp time. Statin therapy had no impact on postoperative inflammatory markers. Freedom from AF was more frequent in the statin group at discharge (P=0.07) and after three and six months (P<0.05). Subgroup analysis showed that statin pretreatment was associated with higher rates of freedom from AF for paroxysmal AF at three and six months and for persistent AF after six months (P<0.05). Importantly, statin-pretreatment was independently predictive for freedom from AF at discharge [odds ratio (OR): 3.21; 95% confidence interval (CI): 1.2-8.55; P=0.02] and at three months (OR: 2.91; 95% CI: 1.14-7.45; P=0.026). Statin therapy prior to ablation surgery improves postoperative freedom from AF for paroxysmal and persistent AF in cardiac surgery patients.

Pulmonary trunk perforation during transapical minimal invasive aortic valve replacement.

In this case report we illustrate our experience with a perforation of the pulmonary trunk during a transapical aortic valve implantation in a single case. The patient suffered from an aortic valve stenosis and was accepted for a minimally invasive procedure because of multiple comorbidities. After unproblematic transapical placement of the aortic valve, a venous bleeding from the anterolateral wound was observed. Median sternotomy showed a bleeding out of the pulmonary trunk that could be stopped with purse-string sutures. The further course of the patient was uneventful.

Successful transapical aortic valve replacement in a patient with a previous mechanical mitral valve replacement.

In this case we illustrate our experience with transapical minimal invasive aortic valve replacement in a patient who previously underwent mitral valve replacement. The implantation did not interfere with the existing prosthesis and could even be used as a further landmark, helping height positioning of the aortic valve.

Temperature dependence of cerebral blood flow for isolated regions of the brain during selective cerebral perfusion in pigs.

BACKGROUND: Hypothermic circulatory arrest (HCA) and antegrade selective cerebral perfusion (ASCP) are utilized for cerebral protection during aortic surgery. However, no consensus exists regarding optimal ASCP-temperature showing a tendency toward higher values during the last years. This study investigates regional changes of cerebral blood flow (CBF) during ASCP at two temperatures. METHODS: In this blinded study, 20 pigs (35 to 37 kg) were randomized to two groups. Animals were cooled to 10 minutes of HCA followed by 60 minutes of ASCP. Afterward the animals were perfused at 25 degrees C and 30 degrees C according to the study group. Fluorescent microspheres were injected at seven time points during the experiment to calculate total and regional CBF. Hemodynamics, cerebrovascular resistance (CVR) and cerebral metabolic rate of oxygen (CMRO(2)) were assessed. Tissue samples from the cortex, cerebellum, hippocampus, and pons were taken for microsphere count. RESULTS: The CBF and CMRO(2) decreased significantly (p < 0.002) during cooling in both groups; it was significantly higher throughout ASCP in the 30 degrees C versus the 25 degrees C group (p = 0.0001). These findings were similar among all brain regions, certainly at different levels. The CBF increased significantly (p = 0.002) during the early period of ASCP for analyzed regions and decreased significantly (p = 0.034) below baseline after 60 minutes of ASCP, reaching critical levels in the hippocampus and neocortex. The hippocampus turned out to have the lowest CBF, while the pons showed the highest CBF. Thirty minutes and more ASCP provides less CBF compared with baseline values at both temperatures. CONCLUSIONS: Antegrade selective cerebral perfusion improves CBF in all regions of the brain for a limited time. Our study characterizes the brain specific hierarchy of blood flow during ASCP. These dynamics are highly relevant for clinical strategies of perfusion.