Novel concept of less invasive concomitant surgical aortic valve replacement and coronary artery bypass grafting avoiding full median sternotomy.

In the last decades, minimally invasive procedures have been developed in the therapy of aortic valve disorders. Recently, a novel concept of minimally invasive coronary revascularization in multivessel disease via left anterior mini-thoracotomy demonstrated promising results. Full median sternotomy, as a very invasive procedure, is the standard approach in concomitant surgical aortic valve replacement (sAVR) and coronary bypass grafting (CABG). The aim of our study was to show that the combination of minimal invasive aortic valve replacement via upper mini-sternotomy and coronary artery bypass grafting via left anterior mini-thoracotomy is feasible to avoid full median sternotomy. From 07/2022 to 09/2022, concomitant sAVR via upper partial sternotomy and CABG via left anterior mini-thoractomy on cardiopulmonary bypass and cardioplegic arrest was successfully performed in six consecutive patients (6 males; 69.8 ± 7.4 [60-79] years). All patients had severe aortic stenosis (MPG 45.5 ± 17.3 mmHg) and a significant coronary artery disease (three-vessel: 33%, two-vessel: 33%, one-vessel: 33%) with indication to cardiac surgery. Mean EuroScore2 was 3.2. All patients underwent successful less invasive concomitant biological sAVR and CABG. 67% of patients received a 25 mm, 33% received a 23 mm biological aortic valve replacement (Edwards Lifesciences Perimount). A total of 11 distal anastomoses (1.8 ± 1.0 [1-3] per patient) were performed by using left internal artery mammary (50%), radial artery (17%) and saphenous venous graft (67%) for grafting the left anterior descending (83%), circumflex (67%) and right (33%) coronary artery. Hospital mortality was 0%, stroke rate was 0%, myocardial infarction was 0% and repeat revascularization rate was 0%, ICU stay was 1 day in 83% of all patients and 50% left hospital within 8 days after surgery. Less invasive concomitant surgical aortic valve replacement and coronary artery bypass grafting using upper mini-sternotomy and left anterior mini-thoracotomy is feasible without compromises in surgical principles and complete coronary revascularization while maintaining thoracic stability by avoiding full median sternotomy.

Early Results of Total Coronary Revascularization via Left Anterior Thoracotomy.

BACKGROUND: Avoidance of sternotomy while preserving complete revascularization remains challenging in multivessel coronary disease. Technical issues and in-hospital outcomes of total coronary revascularization via a small left anterior thoracotomy (TCRAT) in nonselected patients with multivessel disease are reported. METHODS: From November 2019 to September 2021, coronary artery bypass grafting via left anterior minithoracotomy on cardiopulmonary bypass and cardioplegic cardiac arrest was performed in 102 patients (92 males; 67 ± 10 [42-87] years). Slings were placed around ascending aorta, left pulmonary veins, and inferior vena cava for exposure of lateral and inferior ventricular wall. All patients had multivessel coronary disease (three-vessel disease: n = 72; two-vessel disease: n = 30; left main stenosis: n = 44). We included patients at old age (> 80 years, 14.7%), with severe left ventricular dysfunction (ejection fraction < 30%, 6.9%), massive obesity (body mass index > 35, 11.6%), and at increased risk (EuroSCORE II > 4, 15.7%). RESULTS: Left internal thoracic artery (n = 101), radial artery (n = 83), and saphenous vein (n = 39) grafts were used for total (61.8%) or multiple (19.6%) arterial grafting. A total of 323 distal anastomoses (3.2 ± 0.7 [2-5] per patient) were performed to revascularize left anterior descending (100%), circumflex (91.2%), and right coronary artery (67.7%). Complete revascularization was achieved in 95.1%. In-hospital mortality was 2.9%, stroke rate was 1.0%, myocardial infarction rate was 2.9%, and repeat revascularization rate was 2.0%. CONCLUSION: This novel surgical technique allows complete coronary revascularization in the broad majority of multivessel disease patients without sternotomy. TCRAT can be introduced into clinical routine safely. Long-term results remain to be investigated.

Novel concept of routine total arterial coronary bypass grafting through a left anterior approach avoiding sternotomy.

Coronary artery bypass grafting (CABG) via full sternotomy remains a very invasive procedure, often requiring prolonged recovery of the patient. We describe a novel, less invasive approach for totally arterial CABG via a small left anterior thoracotomy in a pilot series of 20 unselected patients. From January to March 2020, 20 consecutive patients (mean age 65.9 ± 9.2 years, 100% male, STS-score: 1.6 ± 2) underwent CABG using only arterial conduits via a small left anterior thoracotomy. Patients were operated on cardiopulmonary bypass with peripheral cannulation and transthoracic aortic cross-clamping. Pulling tapes encircling the great vessels, the arrested empty heart was rotated and moved within the pericardium to enable conventional anastomotic techniques especially on lateral and inferior wall coronary targets. In all patients, left internal mammary artery and radial artery were utilized for bypass with 3.3 ± 0.7 distal coronary anastomoses per patient. Anterior, lateral, and inferior wall territories were revascularized in 100%, 85%, and 70% of patients, respectively. Complete anatomical revascularization was achieved in 95% of patients. ICU stay was 1 day in 17 patients, and 14 of patients left the hospital within 8 days. There was no hospital death, no stroke, no myocardial infarction, and no repeat revascularization. In this pilot series of 20 patients, minimally invasive, totally arterial CABG with avoidance of sternotomy was technically feasible with favorable patient outcomes.

Renal Outcome in Patients Undergoing Minimally Invasive Total Coronary Revascularization via Anterior Minithoracotomy Compared to Full Median Sternotomy Coronary Artery Bypass Grafting.

Objective: Renal dysfunction and acute renal failure after coronary artery bypass grafting (CABG) are among the main causes of increased mortality and morbidity. A sternum-sparing concept of minimally invasive total coronary revascularization via anterior minithoracotomy (TCRAT) was introduced with promising early and midterm outcomes in multivessel coronary artery disease. There are limited data regarding renal complications in patients undergoing the TCRAT technique. The present study analyzed renal outcomes in TCRAT compared to CABG via full median sternotomy (FS). Methods: We analyzed the records of 227 consecutive TCRAT patients (from September 2021 to June 2023) and 228 consecutive FS patients (from January 2017 to December 2018) who underwent nonemergent CABG. Following propensity score matching, preoperative baseline characteristics-including age, sex, diabetes mellitus, arterial hypertension, left ventricular ejection fraction, EuroSCORE II, preoperative serum creatinine, estimated glomerular filtration rate (eGFR), serum urea, and pre-existing chronic renal insufficiency-were comparable between the TCRAT (n = 170) and the FS group (n = 170). The examined postoperative renal parameters and complications were serum creatinine, eGFR, and serum urea on the first postoperative day. Moreover, serum creatinine, eGFR and serum urea at the time of discharge, postoperative ARF, and hemodialysis were investigated. Additionally, the duration of operation, CPB time, aortic cross-clamp time, ICU and hospital stay, ECMO support, rethoracotomy and in-hospital mortality were analyzed. The parameters were compared between groups using a Student's t-test or Mann-Whitney U test. Results: The duration of operation (332 ± 66 vs. 257 ± 61 min; p < 0.05), CPB time (161 ± 40 vs. 116 ± 38 min; p < 0.05), and aortic cross-clamp time (100 ± 31 vs. 76 ± 26; p < 0.05) were longer in the TCRAT group. ICU (1.8 ± 2.2 vs. 2.9 ± 3.6 days; p < 0.05) and hospital (10.4 ± 7.6 vs. 12.4 ± 7.5 days; p < 0.05) stays were shorter in the TCRAT group. There were no differences between groups with regard to the renal parameters examined. Conclusions: Despite a prolonged duration of operation, CPB time, and aortic cross-clamp time when using the TCRAT technique, no increase in renal complications were found. In addition, ICU and hospital stays in the TCRAT group were shorter compared to CABG via full median sternotomy.

Sternum-sparing multivessel coronary surgery as a routine procedure: Midterm results of total coronary revascularization via left anterior thoracotomy.

Objective: A sternum-sparing approach of minimally invasive total coronary revascularization via left anterior thoracotomy demonstrated promising early outcomes in unselected patients with coronary artery multivessel disease. Follow-up data are still missing. Methods: From November 2019 to September 2023, coronary artery bypass grafting via left anterior minithoracotomy on cardiopulmonary bypass and cardioplegic cardiac arrest was performed as a routine procedure in 392 consecutive, nonemergency patients (345 men; 67.0 ± 9.9 years; range, 32-88 years). All patients had multivessel coronary artery disease (77.6% 3-vessel-disease, 22.4% 2-vessel-disease, and 32.9% left main stenosis). Patients at old age (older than a 80 years, 12.5%), with severe left ventricular dysfunction (ejection fraction <30%, 7.9%), diabetes mellitus (34.9%), massive obesity (body mass index > 35, 8.9%), and chronic lung disease (17.1%) were included. Mean European System for Cardiac Operative Risk Evaluation II score was 2.9 ± 2.8. Mean midterm follow-up (100%) was 15.2 ± 10.7 months (range, 0.1-39.5 months). Results: Left internal thoracic artery (99.0%), radial artery (70.4%), and saphenous vein grafts (57.4%) were used, and 70.4% of patients received at least 2 arterial grafts. A total of 3.0 ± 0.8 anastomoses (range, 2-5 anastomoses) per patient were performed to revascularize the territories of left anterior descending (98.7%), circumflex (91.6%), and right coronary (70.9%) artery. Complete anatomical revascularization was achieved in 95.1%. At follow-up, all-cause-mortality, myocardial infarction, repeat revascularization, and stroke was 3.1%, 1.5%, 5.4%, and 0.7%, respectively. Overall major adverse cardiac and cerebrovascular events rate was 8.7%. Conclusions: This is the first report of midterm follow-up after routine sternum-sparing total coronary revascularization via left anterior thoracotomy for multivessel coronary artery disease with a high rate of multiple arterial grafting and complete anatomical revascularization. Outcome was favorable and similar to that of contemporary conventional coronary artery bypass grafting.

Incidence of deep sternal wound infection is not reduced with autologous platelet rich plasma in high-risk cardiac surgery patients.

BACKGROUND: Deep sternal wound infections (DSWI) remain a devastating complication in cardiac surgery applying full sternotomy. As the risk profile in cardiac surgery changed toward an older and sicker population, the incidence of DSWI increases. Platelet rich plasma (PRP) holds promise in tissue regeneration with respect to bone regeneration, reduction of bleeding, and accelerated wound healing. The effect of PRP on DSWI was investigated in high-risk patients undergoing cardiac surgery with full sternotomy. METHODS: 196 consecutive patients at risk of DSWI were randomized to application of autologous PRP before sternal wiring (n = 97) or control (n = 99). All patients underwent cardiac surgery on cardiopulmonary bypass with cardioplegic cardiac arrest. Endpoint was occurrence of DSWI requiring revision surgery. RESULTS: Demographic, intraoperative, and perioperative variables as well as risk factors were comparable between groups. Incidence of DSWI was not different between the PRP-group and the control-group (6/97 (6.2%) vs. 3/99 (3.0%); n.s.). CONCLUSIONS: Local application of autologous PRP in cardiac surgery patients with full sternotomy at high risk for sternal complications did not reduce the incidence of DSWI.

Development of In-Hospital Outcomes in Patients undergoing Transcatheter Aortic Valve Implantation (TAVI) at an Interdisciplinary Heart Center: A Single-Center Experience of 489 Consecutive Cases.

Background: Transcatheter Aortic Valve Implantation (TAVI) has emerged over time, reflected in appropriate adjustments in the European Society of Cardiology (ESC) guidelines in 2007, 2012 and 2017. Objective: The aim of this study was to analyze in-hospital outcomes after TAVI in the development within a single heart center over a period of 10 years depending on adjustments in the guidelines, infrastructural and procedural determinants. Methods: 489 consecutive patients who underwent TAVI from 2010 and 2019 at our center were analyzed retrospectively. Patients were divided into 3 groups of different treatment circumstances depending on guidelines adjustments and local infrastructural progress (group 1: 2010-2015 (n = 132), group 2: 2016-2017 (n = 155), group 3: 2018-2019 (n = 202). The primary endpoint was defined as all-cause in-hospital mortality. Secondary endpoints were selected according to the Valve Academic Research Consortium (VARC)-2 definitions. Multivariate logistic regression analysis was performed to determine predictors of in-hospital mortality. Statistical significance was assumed for p < 0.05. Results: 489 patients (346 (70.8 %) transfemoral and 143 (29.2 %) transapical) underwent TAVI. Comparing periods (group 1 vs. 2 vs. 3) age (82.1 ± 6.2 vs. 82.5 ± 4.8 vs. 81.1 ± 5.1 years, p = 0.012) and EuroSCORE II (8.4 ± 6.0 vs. 5.8 ± 4.9 vs. 5.5 ± 5.0 %, p < 0.001) declined over time. Rates of in-hospital mortality decreased significantly (9.1 % vs. 5.8 % vs. 2.5 %, p = 0.029), especially with observed-to-expected mortality ratios indicating a disproportionate decline of in-hospital mortality (1.08 vs. 1.00 vs. 0.45). Furthermore, post-procedural complications, such as acute kidney injury stage 3 (10.6 % vs. 3.2 % vs. 4.5 %, p = 0.016) and bleeding complications (14.4 % vs. 11.6 % vs 7.9 %, p = 0.165) decreased from group 1 to 3. However, rates of permanent pacemaker implantations (7.6 % vs. 11.0 % vs. 22.8 %, p < 0.001) increased, associated with a switch towards self-expanding valves (0.0 % vs. 61.3 % vs. 76.7 %, p < 0.001). Length of hospitalization as well as stay at intensive care and intermediate care unit could be reduced significantly during the observation period. In multivariate analysis age (OR: 1.103; 95 % CI: 1.013 - 1.202; p = 0.025), creatinine level before TAVI (OR: 1.497; 95 % CI: 1.013 - 2.212; p = 0.043), atrial fibrillation (OR: 2.956; 95 % CI: 1.127 - 7.749; p = 0.028) and procedure duration (OR: 1.017; 95 % CI: 1.009 - 1.025; p < 0.001) could be identified as independent predictors of in-hospital mortality. Conclusion: This study identified age, creatinine level before TAVI, the presence of atrial fibrillation and procedure duration as independent predictors for in-hospital mortality. Although these predictors decreased during the observation period, the decline in hospital-mortality was disproportionate, which was indicated by an observed-to-expected mortality ratio of 0.45 for the last observation period. However, it can be assumed that apart from patient-related factors, there were further institutional, technical and procedural developments, which ran in parallel and affected in-hospital mortality rates after TAVI.

[Impact of the COVID-19 pandemic on cardiac surgery]. / Auswirkungen der COVID-19-Pandemie auf die Herzchirurgie.

Since the beginning of 2020, the coronavirus disease 2019 (COVID-19) pandemic had a massive impact on and also changed life worldwide and serious consequences have naturally been observed particularly in the healthcare sector. These affect patients as well as medical personnel of all professional groups, both in the outpatient and inpatient areas. As expected, cardiac surgery as a discipline that is more dependent than any other on available capacity in intensive care units, was severely affected by the impact of the pandemic. This article provides an overview of the consequences for clinical care, research and teaching as well as for continuing education in cardiac surgery.

Transcatheter mitral valve implantation versus conventional redo surgery for degenerated mitral valve prostheses and rings in a multicenter registry.

OBJECTIVES: Degeneration of mitral prostheses/rings may be treated by redo surgery, and, recently, by transcatheter valve-in-valve/ring implantation. This multicenter registry presents results of transcatheter valve-in-valve and repeat surgery for prostheses/rings degeneration. METHODS: Data provided by 10 German heart centers underwent propensity score-matched retrospective analysis. The primary endpoint was 30-day/midterm mortality. Perioperative outcome was assessed according to the Mitral Valve Academic Research Consortium criteria. Further, the influence of moderate or greater tricuspid regurgitation (TR) on 30-day/midterm mortality was analyzed. RESULTS: Between 2014 and 2019, 273 patients (79 transcatheter mitral valve-in-valve [TM-ViV] and 194 redo mitral valve replacement [Re-MVR]) underwent repeat procedure for mitral prosthesis/ring degeneration. Propensity score matching distinguished 79 patient pairs. European System for Cardiac Operative Risk Evaluation (EuroSCORE) II-predicted risk was 15.7 ± 13.7% in the TM-ViV group and 15.0% ± 12.7% in the Re-MVR group (P = .5336). TM-ViV patients were older (74.73 vs 72.2 years; P = .0030) and had higher incidence of atrial fibrillation (54 vs 40 patients; P = .0233). Severe TR incidence was similar (17.95% in TM-ViV vs 14.10%; P = .1741). Sixty-eight TM-ViV patients previously underwent mitral valve replacement, whereas 41 Re-MVR patients underwent valve repair (P < .0001). Stenosis was the leading degeneration mechanism in 42 TM-ViV versus 22 Re-MVR patients (P < .0005). The 30-day/midterm mortality did not differ between groups. Moderate or greater TR was a predictor of total (odds ratio [OR], 4.36; P = .0011), 30-day (OR, 3.76; P = .0180), and midterm mortality (OR, 4.30; P = .0378), irrespective of group. CONCLUSIONS: In both groups, observed mortality was less than predicted. Redo surgery enabled treatment of concomitant conditions, such as atrial fibrillation or TR. TR was shown to be a predictor of total, 30-day, and midterm mortality in both groups.

Extravascular perivenous fibrin support leads to aneurysmal degeneration and intimal hyperplasia in arterialized vein grafts in the rat.

BACKGROUND AND AIMS: External support of vein grafts by fibrin glue possibly prevents overdistension, vascular remodeling, and neointimal hyperplasia. Previous animal models of neointimal hyperplasia showed conflicting results. Here, long-term effects of external fibrin glue support were studied in a new rat model of jugular vein to abdominal aorta transposition. MATERIALS AND METHODS AND METHODS: In male Wistar rats (250-300 g) right jugular vein (1.0-1.5 cm) was transposed to the infrarenal aorta. Fibrin glue (0.25 ml) covered the vein before releasing the vascular clamps (n = 6). Control vein grafts were exposed directly to blood pressure. After 16 weeks vein grafts were pressure-fixed for histology. Intima thickness, luminal and intimal area were measured by planimetry and elastic fibers demonstrated by Elastica van Giesson staining. RESULTS: Intimal thickness (74.04 +/- 6.7 microm vs 1245 +/- 187 microm, control vs fibrin treatment; p < 0.001), intimal area (2517.16 +/- 355 mm(2) vs 18424 +/- 4927 mm(2), control vs fibrin treatment; p < 0.05) and luminal area (2184.75 +/- 347 mm(2) vs 7231.85 +/- 1782 mm(2), control vs fibrin treatment; p < 0.05) were significantly increased, elastic fibers in the vessel wall were diminished and the vessel wall infiltrated by mononuclear cells in fibrin glue supported veins. CONCLUSION: External support of vein grafts by fibrin glue leads to aneurysmal degeneration and intimal hyperplasia, thereby possibly jeopardizing long-term graft patency.

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.

Angiotensin II and myosin light-chain phosphorylation contribute to the stretch-induced slow force response in human atrial myocardium.

AIMS: Stretch is an important regulator of atrial function. The functional effects of stretch on human atrium, however, are poorly understood. Thus, we characterized the stretch-induced force response in human atrium and evaluated the underlying cellular mechanisms. METHODS AND RESULTS: Isometric twitch force of human atrial trabeculae (n = 252) was recorded (37 degrees C, 1 Hz stimulation) following stretch from 88 (L88) to 98% (L98) of optimal length. [Na(+)](i) and pH(i) were measured using SBFI and BCECF epifluorescence, respectively. Stretch induced a biphasic force increase: an immediate increase [first-phase, Frank-Starling mechanism (FSM)] to approximately 190% of force at L88 followed by an additional slower increase [5-10 min; slow force response (SFR)] to approximately 120% of the FSM. FSM and SFR were unaffected by gender, age, ejection fraction, and pre-medication with major cardiovascular drugs. There was a positive correlation between the amplitude of the FSM and the SFR. [Na(+)](i) rose by approximately 1 mmol/L and pH(i) remained unchanged during the SFR. Inhibition of Na(+)/H(+)-exchange (3 microM HOE642), Na(+)/Ca(2+)-exchange (5 microM KB-R7943), or stretch-activated channels (0.5 microM GsMtx-4 and 80 microM streptomycin) did not reduce the SFR. Inhibition of angiotensin-II (AngII) receptors (5 microM saralasin and 0.5 microM PD123319) or pre-application of 0.5 microM AngII, however, reduced the SFR by approximately 40-60%. Moreover, stretch increased phosphorylation of myosin light chain 2 (MLC2a) and inhibition of MLC kinase (10 microM ML-7 and 5 microM wortmannin) decreased the SFR by approximately 40-85%. CONCLUSION: Stretch elicits a SFR in human atrium. The atrial SFR is mediated by stretch-induced release and autocrine/paracrine actions of AngII and increased myofilament Ca(2+) responsiveness via phosphorylation of MLC2a by MLC kinase.

Three reactive compartments in venous malformations.

Vascular malformations affect 3% of neonates. Venous malformations (VMs) are the largest group representing more than 50% of cases. In hereditary forms of VMs gene mutations have been identified, but for the large group of spontaneous forms the primary cause and downstream dysregulated genes are unknown. We have performed a global comparison of gene expression in slow-flow VMs and normal saphenous veins using human whole genome micro-arrays. Genes of interest were validated with qRT-PCR. Gene expression in the tunica media was studied after laser micro-dissection of small pieces of tissue. Protein expression in endothelial cells (ECs) was studied with antibodies. We detected 511 genes more than four-fold down- and 112 genes more than four-fold up-regulated. Notably, chemokines, growth factors, transcription factors and regulators of extra-cellular matrix (ECM) turnover were regulated. We observed activation and "arterialization" of ECs of the VM proper, whereas ECs of vasa vasorum exhibited up-regulation of inflammation markers. In the tunica media, an altered ECM turnover and composition was found. Our studies demonstrate dysregulated gene expression in tunica interna, media and externa of VMs, and show that each of the three layers represents a reactive compartment. The dysregulated genes may serve as therapeutic targets.

The impact of subarachnoid hemorrhage on regional cerebral blood flow and large-vessel diameter in the canine model of chronic vasospasm.

OBJECTIVE: The aim of this study was to correlate changes in regional cerebral blood flow (rCBF) to the degree of cerebral vasospasm in the canine two-hemorrhage model of subarachnoid hemorrhage (SAH). METHODS: SAH was induced in 13 adult beagle dogs using the two-hemorrhage model. Eleven beagle dogs served as controls. Angiography of the basilar artery and measurements of rCBF with colored microspheres were performed on days 1 and 8. Diameter of the basilar artery was calculated at equidistant points from the angiogram. RESULTS: In controls, basilar artery diameter (mm) and rCBF (mL/min/g) were equal on days 1 and 8. In the SAH group, basilar artery diameter decreased significantly (1.27 +/- 0.17 [mean +/- SD]-0.84 +/- 0.15 mm). rCBF decreased significantly (P < .05) in the cerebrum (1.69 +/- 0.54 [mean +/- SD]-1.06 +/- 0.45 mL/min/g), cerebellum (1.18 +/- 0.40-0.80 +/- 0.32 mL/min/g), and brain stem (0.81 +/- 0.33-0.51 +/- 0.21 mL/min/g). However, decrements in CBF were not correlated to the reduction in vessel caliber in the corresponding vascular territory. CONCLUSION: Induced SAH in the canine model produces a significant impairment in rCBF irrespective of the degree of vasospasm of large cerebral vessels. The findings support the presumptive role of the microvasculature in regard to delayed cerebral ischemia after SAH.

Myocardial dysfunction with coronary microembolization: signal transduction through a sequence of nitric oxide, tumor necrosis factor-alpha, and sphingosine.

Coronary microembolization results in progressive myocardial dysfunction, with causal involvement of tumor necrosis factor-alpha (TNF-alpha). TNF-alpha uses a signal transduction involving nitric oxide (NO) and/or sphingosine. Therefore, we induced coronary microembolization in anesthetized dogs and studied the role and sequence of NO, TNF-alpha, and sphingosine for the evolving contractile dysfunction. Four sham-operated dogs served as controls (group 1). Eleven dogs received placebo (group 2), 6 dogs received the NO synthase inhibitor N(G)-nitro-L-arginine methyl ester (L-NAME, group 3), and 6 dogs received the ceramidase inhibitor N-oleoylethanolamine (NOE, group 4) before microembolization was induced by infusion of 3000 microspheres (42-microm diameter) per milliliter inflow into the left circumflex coronary artery. Posterior systolic wall thickening (PWT) remained unchanged in group 1 but decreased progressively in group 2 from 20.6+/-4.9% (mean+/-SD) at baseline to 4.1+/-3.7% at 8 hours after microembolization. Leukocyte count, TNF-alpha, and sphingosine contents were increased in the microembolized posterior myocardium. In group 3, PWT remained unchanged (20.3+/-2.6% at baseline) with intracoronary administration of L-NAME (20.8+/-3.4%) and 17.7+/-2.3% at 8 hours after microembolization; TNF-alpha and sphingosine contents were not increased. In group 4, PWT also remained unchanged (20.7+/-4.6% at baseline) with intravenous administration of NOE (19.5+/-5.7%) and 16.4+/-6.3% at 8 hours after microembolization; TNF-alpha, but not sphingosine content, was increased. In all groups, systemic hemodynamics, anterior systolic wall thickening, and regional myocardial blood flow remained unchanged throughout the protocols. A signal transduction cascade of NO, TNF-alpha, and sphingosine is causally involved in the coronary microembolization-induced progressive contractile dysfunction.

Myocardial ischemia tolerance in the newborn rat involving opioid receptors and mitochondrial K+ channels.

Neonatal rat hearts are more tolerant to ischemia compared to adult rat hearts. We hypothesized that opioid receptors and mitochondrial potassium channels are involved in the elevated ischemia tolerance of neonatal rats. Newborn rats were treated by an intraperitoneal injection with sodium chloride (placebo, Pla; n = 7), naloxone (Nal; n = 8), or K+ (ATP) channel blocker 5-hydroxydecanoate (HD; n = 8), or were left untreated (sham; n = 8). Thirty minutes after injection, the rats were sacrificed and hearts were arrested cardioplegically and fixed with aldehyde fixative 90 min after global ischemia at room temperature. For control, newborn rat hearts were fixed immediately after sacrifice. Ventricular tissue blocks were prepared for electron microscopy. Mitochondrial (volume-weighted mean volume of mitochondria) and cardiomyocyte volume (cellular edema index, CEI) were estimated to quantify the ischemic injury. Compared to control myocardium, CEI was increased by 244% +/- 39% in sham, 173% +/- 28% in Nal, 142% +/- 25% in HD, and 101% +/- 24% in Pla (P < 0.05 between groups). Volume-weighted mean volume of mitochondria was increased by 514% +/- 235% in sham, 341% +/- 110% in Nal, 458% +/- 149% in HD, and 175% +/- 70% in Pla. Differences between Pla and other groups were significant (P < 0.01 for all). No significant difference was observed between the other groups. Thus, ischemic injury was smallest with placebo, indicating a mechanism similar to preconditioning induced by the intraperitoneal injection. This response was attenuated by blockade of opioid receptors and mitochondrial potassium channels, suggesting their involvement in the elevated ischemia tolerance of newborn rat hearts.

Prevention of TNFalpha-associated myocardial dysfunction resulting from cardiopulmonary bypass and cardioplegic arrest by glucocorticoid treatment.

OBJECTIVE: Cardiac surgery on cardiopulmonary bypass (CPB) results in progressive myocardial dysfunction, despite unimpaired coronary blood flow, and is associated with increased myocardial tumor necrosis factor-alpha (TNFalpha) expression. We investigated whether anti-inflammatory treatment prevents increased TNFalpha expression and myocardial dysfunction after CPB. METHODS AND RESULTS: Baseline systemic hemodynamics, myocardial contractile function, aortic and coronary blood flow were measured in anesthetized pigs. Then, placebo (PLA; saline; n=7) or methylprednisolone (MP; 30 mg/kg; n=6) was infused intravenously and CPB was instituted. Global ischemia was induced for 10 min by aortic cross-clamping, followed by 1 h of cardioplegic cardiac arrest. After declamping and reperfusion, CPB was terminated after a total of 3 h. Measurements were repeated at 15 min, 4 h, and 8 h following termination of CPB. Systemic TNFalpha-plasma concentrations and left ventricular TNFalpha expression were analyzed. With unchanged coronary blood flow in both groups, a progressive loss of myocardial contractile function to 38+/-2% of baseline (p<0.01) and cardiac index to 48+/-6% of baseline (p<0.01) at 8 h after CPB in PLA was attenuated in MP (myocardial function: 72+/-3%, p<0.01 vs PLA; cardiac index: 78+/-6%, p<0.05 vs PLA). Systemic TNFalpha was increased at 8 h in PLA compared to MP (243+/-34 vs 90+/-34 pg/ml, p<0.05). Myocardial TNFalpha was increased at 8 h after CPB compared to baseline and MP (p<0.05). Myocardial TNFalpha immunostaining was more pronounced in PLA than in MP (p<0.05), with TNFalpha-mRNA localization predominantly to cardiomyocytes. CONCLUSIONS: Methylprednisolone attenuates both systemic and myocardial TNFalpha increases and progressive myocardial dysfunction induced by cardiac surgery, suggesting a key role for TNFalpha.

Description of a Heart Team approach to coronary revascularization and its beneficial long-term effect on clinical events after PCI.

OBJECTIVE AND BACKGROUND: We present a first description of a Heart Team (HT)-guided approach to coronary revascularization and its long-term effect on clinical events after percutaneous coronary intervention (PCI). The HT approach is a structured process to decide for coronary bypass grafting (CABG), PCI or conservative therapy in ad hoc situations as well as in HT conferences. As a hypothesis, during the long-term course after a PCI performed according to HT rules, a low number of late revascularizations, especially CABGs, are expected (F-PCI study). METHODS: In this monocentric study, the HT approach to an all-comer population was first analyzed and described in general with the help of a database. Next the use of a HT approach was described for a more homogeneous subgroup with newly detected CAD (1.CAD). Those patients in whom the HT decision was PCI (which was a 1.PCI) were then studied with the help of questionnaires for clinical events during a very long-term follow-up. Events were CABG, PCI, diagnostic catheterization (DCath) and death. RESULTS: A significant number of patients were presented to HT conferences: 22 % out of all 11,174 catheterizations, 24 % out of all 7867 CAD cases and 35 % out of 3408 1.CAD cases. Most of these patients had multi-vessel disease (MVD). Conference decisions were isolated CABG in 46-66 %, PCI in 10-14 %, valvular surgery in 9-16 %, HTx in 10-21 % (Endstage heart failure candidates for surgery) and conservative therapy (Medical or no therapy, additional diagnostic procedures or no adherence to recommended therapy) in 2-3 %. However, most PCIs, ad hoc and elective, were performed under Heart Team rules, but without conference. During follow-up of 1.PCI patients (Kaplan-Meier analysis), CABG occurred in only 15 % of patients, PCI in 37 % and DCath in 65 %; mortality of any course was 51 %. Mortalities were similar in one-vessel disease and in a population of the same year, matched for age and sex (p < 0.057), but mortality was higher in 1.PCI patients with MVD (p < 0.001). Beyond 2 years, Kaplan-Meier curves were linear. CONCLUSION: The structured Heart Team approach is an effective tool for ad hoc and conference-based clinical decision-making with a sustained clinical benefit. This is demonstrated in low late CABG (and PCI) rates after a 1.PCI, without elevated mortality. The all-comer population supports the universal value of these data. Stable annual event rates late after PCI suggest a conversion to stable CAD. Heart Team conferences are also important tools in cases of valvular and end-stage heart disease.

Glucocorticoid treatment prevents progressive myocardial dysfunction resulting from experimental coronary microembolization.

BACKGROUND: The frequency and importance of microembolization in patients with acute coronary syndromes and during coronary interventions have recently been appreciated. Experimental microembolization induces immediate ischemic dysfunction, which recovers within minutes. Subsequently, progressive contractile dysfunction develops over several hours and is not associated with reduced regional myocardial blood flow (perfusion-contraction mismatch) but rather with a local inflammatory reaction. We have now studied the effect of antiinflammatory glucocorticoid treatment on this progressive contractile dysfunction. METHODS AND RESULTS: Microembolization was induced by injecting microspheres (42-microm diameter) into the left circumflex coronary artery. Anesthetized dogs were followed up for 8 hours and received placebo (n=7) or methylprednisolone 30 mg/kg IV either 30 minutes before (n=7) or 30 minutes after (n=5) microembolization. In addition, chronically instrumented dogs received either placebo (n=4) or methylprednisolone (n=4) 30 minutes after microembolization and were followed up for 1 week. In acute placebo dogs, posterior systolic wall thickening was decreased from 20.0+/-2.1% (mean+/-SEM) at baseline to 5.8+/-0.6% at 8 hours after microembolization. Methylprednisolone prevented the progressive myocardial dysfunction. Increased leukocyte infiltration in the embolized myocardium was prevented only when methylprednisolone was given before microembolization. In chronic placebo dogs, progressive dysfunction recovered from 5.0+/-0.7% at 4 to 6 hours after microembolization back to baseline (19.1+/-1.6%) within 5 days. Again, methylprednisolone prevented the progressive myocardial dysfunction. CONCLUSIONS: Methylprednisolone, even when given after microembolization, prevents progressive contractile dysfunction.