13-year single-center experience with the treatment of acute type B aortic dissection

Background. Acute type B aortic dissection (TBAD) is catastrophic event associated with significant mortality and lifelong morbidity. The optimal treatment strategy of TBAD is still controversial. Methods. This analysis includes patients treated for TBAD at the Helsinki University Hospital, Finland in 2007-2019. The endpoints were early and late mortality, and intervention of the aorta. Results. There were 205 consecutive TBAD patients, 59 complicated and 146 uncomplicated patients (mean age of 66 +/- 14, females 27.8%). In-hospital and 30-day mortality rates were higher in complicated patients compared with uncomplicated patients with a statistically significant difference (p = 0.035 and p = 0.015, respectively). After a mean follow-up of 4.9 +/- 3.8 years, 36 (25.0%) and 22 (37.9%) TBAD -related adverse events occurred in the uncomplicated and complicated groups, respectively (p = 0.066). Freedom from composite outcome was 83 +/- 3% and 69 +/- 6% at 1 year, 75 +/- 4% and 63 +/- 7% at 5 years, 70 +/- 5% and 59 +/- 7% at 10 years in the uncomplicated group and in the complicated group, respectively (p = 0.052). There were 25 (39.1%) TBAD-related deaths in the overall series and prior aortic aneurysm was the only risk factor for adverse aortic-related events in multivariate analysis (HR 3.46, 95% CI 1.72-6.96, p < 0.001). Conclusion. TBAD is associated with a significant risk of early and late adverse events. Such a risk tends to be lower among patients with uncomplicated dissection, still one fourth of them experience TBAD-related event. Recognition of risk factors in the uncomplicated group who may benefit from early aortic repair would be beneficial.Peer reviewe

Remote ischemic preconditioning in aortic surgery:Experimental studies with a porcine model

Abstract During cardiac and aortic surgery, disturbance of the blood supply in the central nervous system occurs when the repair of aortic pathologies is performed or a bloodless operation field is needed in complex cardiac surgery. To enable the suitable operation environment, the technique named hypothermic circulatory arrest (HCA) has been utilized via heart-lung machine. In this method, the core temperature is lowered to the target temperature, after which blood circulation is halted for a certain period of time. A challenge is that the successful usage of HCA, however still involves the risks of postoperative neurological complications and mortality. In cardiac and aortic arch surgery, the brain is at the highest risk for deficits, whereas in the repair of thoracoabdominal aortic aneurysms (TAAAs), spinal cord injury remains the most severe adverse outcome. Adjunctive protective strategies are required to reduce ischemic injury in these settings. In this thesis, Studies I and II focused on the spinal cord and the Study III on the brain. The studies were performed using acute (II, III) or subacute (I) experimental porcine models, primarily aiming to assess the effectiveness of remote ischemic preconditioning (RIPC) in spinal cord protection along with the aim of studying the underlying mechanisms of RIPC in neuroprotection. Studies I and II demonstrated enhanced motor evoked potential (MEP) responses in both hind limbs, indicating spinal cord protection by RIPC. The faster recovery of brain damage marker S100B along with higher cardiac index and lower systemic lactate levels confirmed the cardio- and neuroprotective properties of RIPC in Study III. The protective mechanism of RIPC was associated with increased antioxidant response (II, III).Tiivistelmä Sydän- ja aorttakirurgiassa, keskushermoston verenkiertoa joudutaan häiritsemään toteutettaessa aortan korjausleikkauksia tai vaikeissa sydänkirurgisissa toimenpiteissä verettömän leikkausalueen saavuttamiseksi. Sydän-keuhkokoneen avulla toteutettava täydellinen verenkierron pysäytys mahdollistaa vaaditut olosuhteet. Tässä menetelmässä ydinlämpötilaa lasketaan ja verenkierron pysäytys toteutaan tavoitellussa kohdelämpötilassa tietyssä aikaikkunassa. Kyseisen menetelmän onnistunut käyttö sisältää kuitenkin riskejä operaatioiden jälkeisiin neurologisiin komplikaatioihin ja kuolleisuuteen. Sydämen ja aortankaaren kirurgiassa aivot ovat suurimmassa vaarassa vaurioille. Rinta- ja vatsa-aortan aneurysmien eli pullistumien korjausleikkauksiin liittyvä selkäydinvaurio on puolestaan yksi vakavimmista ja vaikeimmista seurauksista. Lisäsuojausmenetelmiä tarvitaan vähentämään iskeemistä vauriota näissä asetelmissa. Väitöskirjan osatyöt I ja II keskittyivät selkäytimeen. Osatyö III käsitteli puolestaan aivojen suojausta. Osatyöt toteutettiin akuutteina (II, III) ja subakuutteina (I) kokeellisina porsasmalleina. Tutkimusten tavoitteina oli arvioida esialtistavan perifeerisen raajaiskemian vaikuttavuutta selkäytimen suojauksessa sekä tutkia raajaiskemian taustalla olevia mekanismeja hermokudoksen suojauksessa. Osatöissä I, II havaittiin motoristen herätepotentiaalien parantuneita vasteita molemmissa takajaloissa osoittaen esialtistavan raajaiskemian suojaavan selkäydintä simuloidussa rinta-aortan korjaustoimenpiteessä. Osatyö III keskittyi alhaisessa lämpötilassa toteutettavaan täydelliseen verenkierron pysäytykseen. Tässä tutkimuksessa todetut aivovauriomarkkeri S100B tason nopeampi lasku, korkeampi sydänindeksi ja alhaisemmat laktaattitasot varmistivat raajaiskemian sydän- ja hermokudossuojausvaikutusta. Esialtistavan perifeerisen raajaiskemian suojaava mekanismi voidaan liittää parantuneeseen solujen antioksidanttivasteeseen (II, III)

Impact of high-risk features on outcome of acute type B aortic dissection

Background: Acute type B aortic dissection (TBAD) is a severe condition associated with significant morbidity and mortality. The optimal classification and treatment strategy of TBAD remain controversial and inconsistent. Methods: This analysis includes patients treated for acute TBAD at the Helsinki University Hospital, Finland between 2007 and 2019. The endpoints were early and late mortality, intervention of the aorta, and a composite of death and aortic intervention in uncomplicated patients and high-risk patients. Results: This study included 162 consecutive TBAD patients (27.8% females), 114 in the high-risk group and 48 in the uncomplicated group, with a mean age of 67.6 ± 13.9 years. Intramural hematoma was reported in 63 cases (38.9%). The mean follow-up was 5.1 ± 3.9 years. In-hospital/30-day mortality (n = 4; 3.5%) occurred solely in the high-risk group (P = .32). Additionally, TBAD-related adverse events (n = 23; 20.2%) were observed only in the high-risk group (P < .001). The cumulative incidences of the composite TBAD outcome with non–TBAD-related death as a competing risk were 6.6% (95% CI, 1.7%-16.5%) in the uncomplicated group and 29.5% (95% CI, 21.1%-38.3%) in the high-risk group at 5 years and 6.6% (95% CI, 1.7%-16.5%) and 33.0% (95% CI, 23.7%-42.6%) at 10 years (P = .001, Gray test). Extracardiac arteriopathy (subdistribution hazard ratio [SHR], 2.61; 95% CI, 1.08-6.27) and coronary artery disease (SHR, 2.24; 95% CI, 1.07-4.71) were risk factors for adverse aortic-related events in univariable competing-risk regression analysis. Conclusions: Recognition of risk factors underlying adverse events related to TBAD is essential because the disease progression impacts both early and late outcomes. Early aortic repair in high-risk TBAD may reduce long-term morbidity and mortality.Peer reviewe

Impact of high-risk features on outcome of acute type B aortic dissection

Abstract Background: Acute type B aortic dissection (TBAD) is a severe condition associated with significant morbidity and mortality. The optimal classification and treatment strategy of TBAD remain controversial and inconsistent. Methods: This analysis includes patients treated for acute TBAD at the Helsinki University Hospital, Finland between 2007 and 2019. The endpoints were early and late mortality, intervention of the aorta, and a composite of death and aortic intervention in uncomplicated patients and high-risk patients. Results: This study included 162 consecutive TBAD patients (27.8% females), 114 in the high-risk group and 48 in the uncomplicated group, with a mean age of 67.6 ± 13.9 years. Intramural hematoma was reported in 63 cases (38.9%). The mean follow-up was 5.1 ± 3.9 years. In-hospital/30-day mortality (n = 4; 3.5%) occurred solely in the high-risk group (P = 0.32). Additionally, TBAD-related adverse events (n = 23; 20.2%) were observed only in the high-risk group (P &lt; 0.001). The cumulative incidences of the composite TBAD outcome with non–TBAD-related death as a competing risk were 6.6% (95% CI, 1.7%–16.5%) in the uncomplicated group and 29.5% (95% CI, 21.1%–38.3%) in the high-risk group at 5 years and 6.6% (95% CI, 1.7%–16.5%) and 33.0% (95% CI, 23.7%–42.6%) at 10 years (P = 0.001, Gray test). Extracardiac arteriopathy (subdistribution hazard ratio [SHR], 2.61; 95% CI, 1.08–6.27) and coronary artery disease (SHR, 2.24; 95% CI, 1.07–4.71) were risk factors for adverse aortic-related events in univariable competing-risk regression analysis. Conclusions: Recognition of risk factors underlying adverse events related to TBAD is essential because the disease progression impacts both early and late outcomes. Early aortic repair in high-risk TBAD may reduce long-term morbidity and mortality

Remote ischemic preconditioning and hypoxia-induced biomarkers in acute myocardial infarction : study on a porcine model

Objectives. Remote ischemic preconditioning (RIPC) mitigates acute myocardial infarction (AMI). We hypothesized that RIPC reduces the size and severity of AMI and explored molecular mechanisms behind this phenomenon. Design. In two series of experiments, piglets underwent 60 min of the circumflex coronary artery occlusion, resulting in AMI. Piglets were randomly assigned into the RIPC groups (n = 7 + 7) and the control groups (n = 7 + 7). The RIPC groups underwent four 5-min hind limb ischemia-reperfusion cycles before AMI. In series I, the protective efficacy of RIPC was investigated by using biomarkers and echocardiography with a follow-up of 24 h. In series II, the heart of each piglet was harvested for TTC-staining to measure infarct size. Muscle biopsies were collected from the hind limb to explore molecular mechanisms of RIPC using qPCR and Western blot analysis. Results. The levels of CK-MBm (p = 0.032) and TnI (p = 0.007) were lower in the RIPC group. Left ventricular ejection fraction in the RIPC group was greater at the end of the follow-up. The myocardial infarct size in the RIPC group was smaller (p = 0.033). Western blot indicated HIF1a stabilization in the skeletal muscle of the RIPC group. PCR analyses showed upregulation of the HIF target mRNAs for glucose transporter (GLUT1), glucose transporter 4 (GLUT4), phosphofructokinase 1 (PFK1), glyceraldehyde 3-phosphate dehydrogenase (GAPDH), enolase 1 (ENO1), lactate dehydrogenase (LDHA) and endothelial nitric oxidate synthase (eNOS). Conclusions. Biochemical, physiologic, and histologic evidence confirms that RIPC decreases the size of AMI. The HIF pathway is likely involved in the mechanism of the RIPC.Peer reviewe