Aortic dissection remains a challenging clinical scenario, especially when complicated by peripheral malperfusion. Improvements in medical imaging have furthered understanding of the pathophysiology of malperfusion events in association with aortic dissection, including the elucidation of different mechanisms of branch vessel obstruction. Despite these advances, malperfusion syndrome remains a deadly entity with significant mortality. This review presents the latest knowledge regarding the pathogenesis of aortic dissection complicated by malperfusion syndrome, and discusses the diagnostic and therapeutic guidelines for management of this vicious entity.

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Background We sought to determine whether a pilot goal-directed perfusion initiative could reduce the incidence of acute kidney injury after cardiac surgery. Methods On the basis of the available literature, we identified goals to achieve during cardiopulmonary bypass (including maintenance of oxygen delivery >300 mL O2/min/m2 and reduction in vasopressor use) that were combined into a goal-directed perfusion initiative and implemented as a quality improvement measure in patients undergoing cardiac surgery at Johns Hopkins during 2015. Goal-directed perfusion initiative patients were matched to controls who underwent cardiac surgery between 2010 and 2015 using propensity scoring across 15 variables. The primary and secondary outcomes were the incidence of acute kidney injury and the mean increase in serum creatinine within the first 72 hours after cardiac surgery. Results We used the goal-directed perfusion initiative in 88 patients and matched these to 88 control patients who were similar across all variables, including mean age (61 years in controls vs 64 years in goal-directed perfusion initiative patients, P = .12) and preoperative glomerular filtration rate (90 vs 83 mL/min, P = .34). Controls received more phenylephrine on cardiopulmonary bypass (mean 2.1 vs 1.4 mg, P < .001) and had lower nadir oxygen delivery (mean 241 vs 301 mL O2/min/m2, P < .001). Acute kidney injury incidence was 23.9% in controls and 9.1% in goal-directed perfusion initiative patients (P = .008); incidences of acute kidney injury stage 1, 2, and 3 were 19.3%, 3.4%, and 1.1% in controls, and 5.7%, 3.4%, and 0% in goal-directed perfusion initiative patients, respectively. Control patients exhibited a larger median percent increase in creatinine from baseline (27% vs 10%, P < .001). Conclusions The goal-directed perfusion initiative was associated with reduced acute kidney injury incidence after cardiac surgery in this pilot study.

Preoperative S aureus screening with targeted decolonization was associated with reduced MRSA colonization, transmission, and surgical site infections. Duration of preoperative therapy correlated with decreased frequency of postoperative MRSA colonization.

Growing experience with LDS has confirmed early impressions of its aggressive nature and proclivity toward aortic catastrophe. Surgical outcomes are favorable, but reintervention rates are high. Meticulous follow-up with cardiovascular surveillance imaging remain important for management, particularly as clinical LDS subtypes are characterized and more tailored treatment is developed.

BackgroundDiastolic dysfunction (DD) identified on echocardiography predicts mortality after cardiac surgery, however the most useful diastolic parameters for assessment and the association of DD with prolonged mechanical ventilation, ICU re-admission, and hospital length of stay are not established.MethodsWe included patients that underwent coronary artery bypass grafting (CABG), aortic valve replacement (AVR) or a combined procedure (CAB-AVR) from 2010 to 2016, and who had preoperative transthoracic echocardiography (TTE) at our institution within 6 months of the operation. Diastolic function was graded using the transmitral E and A waves and the septal tissue Doppler velocity. We performed logistic regression to assess the association of grade of DD with a composite endpoint of death, prolonged mechanical ventilation, ICU readmission during hospitalization, and hospital length of stay longer than 14 days.ResultsBetween 2010 and 2016, 577 patients were eligible for inclusion. DD was common, with 42% of the cohort manifesting grade II or grade III DD. Rates of death and prolonged ventilation increased across grades of DD and across quartiles of increasing LV filling pressure, assessed by the E/e’ ratio. Adjusting for age, sex, procedure, systolic and diastolic function, both systolic (odds ratio 0.68 95% CI 0.55–0.85 per inter-quartile increase in LVEF) and diastolic function (odds ratio 1.31 95% CI 1.04–1.66 per increasing DD grade) both independently predicted outcome.ConclusionDiastolic dysfunction is common among patients undergoing cardiac surgery and is associated with death, prolonged mechanical ventilation, and prolonged hospital and ICU length of stay independent of systolic dysfunction.

The use left ventricular assist devices (LVAD) as a bridge-to-transplant (BTT) has become a common modality to treat end-stage heart failure. We sought to examine the impact of BTT on long-term survival and quality of life after heart transplant. The population was all adult patients undergoing isolated heart transplantation in the United States between 2007 and 2017. Inclusion criteria covered BTT patients with a LVAD (only Heartmate II [HMII] or HeartWare Ventricular Assist System [HVAD]) and compared these with patients undergoing de novo heart transplantation. Our primary end-point was survival at 1, 2, and 5 years. Secondary end-points were functional status, return to work, and rates of hospital readmission and graft rejection. Unconditional and conditional survival was estimated with the Kaplan-Meier method. The independent influence of BTT on risk-adjusted mortality was determined using Cox proportional hazards models. In this period, 5,584 patients were bridged with an LVAD and 12,295 underwent de novo transplantation. Unconditional survival was 2% higher in de novo patients at 1, 2, and 5 years. After risk adjustment, BTT was associated with increased mortality at each time point. Unadjusted 5 year survival, conditional on 90 day survival, was similar between groups (82.6% vs. 83.4%; p = 0.15). Functional status, return to work, and unadjusted rates of hospital readmission and graft rejection were similar at 1, 2, 5 years. Bridge-to-transplant with LVADs provides excellent survival and similar quality of life to that of patients undergoing de novo heart transplantation. Bridge-to-transplant patients experience a slightly higher mortality rate within 90 days of transplantation.

Hypothermic circulatory arrest (HCA) provides neuroprotection during cardiac surgery but entails an ischemic period that can lead to excitotoxicity, neuroinflammation, and subsequent neurologic injury. Hydroxyl polyamidoamine (PAMAM) dendrimers target activated microglia and damaged neurons in the injured brain, and deliver therapeutics in small and large animal models. We investigated the effect of dendrimer size on brain uptake and explored the pharmacokinetics in a clinically-relevant canine model of HCA-induced brain injury. Generation 6 (G6, ~6.7 nm) dendrimers showed extended blood circulation times and increased accumulation in the injured brain compared to generation 4 dendrimers (G4, ~4.3 nm), which were undetectable in the brain by 48 hrs after final administration. High levels of G6 dendrimers were found in cerebrospinal fluid (CSF) of injured animals with a CSF/serum ratio of ~20% at peak, a ratio higher than that of many neurologic pharmacotherapies already in clinical use. brain penetration (measured by drug CSF/serum level) of G6 dendrimers correlated with the severity of neuroinflammation observed. G6 dendrimers also showed decreased renal clearance rate, slightly increased liver and spleen uptake compared to G4 dendrimers. These results, in a large animal model, may offer insights into the potential clinical translation of dendrimers.