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Refractory cardiac arrest treated with mechanical CPR, hypothermia, ECMO and early reperfusion (the CHEER trial).

INTRODUCTION Many patients who suffer cardiac arrest do not respond to standard cardiopulmonary resuscitation. There is growing interest in utilizing veno-arterial extracorporeal membrane oxygenation assisted cardiopulmonary resuscitation (E-CPR) in the management of refractory cardiac arrest. We describe our preliminary experiences in establishing an E-CPR program for refractory cardiac arrest in Melbourne, Australia. METHODS The CHEER trial (mechanical CPR, Hypothermia, ECMO and Early Reperfusion) is a single center, prospective, observational study conducted at The Alfred Hospital. The CHEER protocol was developed for selected patients with refractory in-hospital and out-of-hospital cardiac arrest and involves mechanical CPR, rapid intravenous administration of 30 mL/kg of ice-cold saline to induce intra-arrest therapeutic hypothermia, percutaneous cannulation of the femoral artery and vein by two critical care physicians and commencement of veno-arterial ECMO. Subsequently, patients with suspected coronary artery occlusion are transferred to the cardiac catheterization laboratory for coronary angiography. Therapeutic hypothermia (33 °C) is maintained for 24h in the intensive care unit. RESULTS There were 26 patients eligible for the CHEER protocol (11 with OHCA, 15 with IHCA). The median age was 52 (IQR 38-60) years. ECMO was established in 24 (92%), with a median time from collapse until initiation of ECMO of 56 (IQR 40-85) min. Percutaneous coronary intervention was performed on 11 (42%) and pulmonary embolectomy on 1 patient. Return of spontaneous circulation was achieved in 25 (96%) patients. Median duration of ECMO support was 2 (IQR 1-5) days, with 13/24 (54%) of patients successfully weaned from ECMO support. Survival to hospital discharge with full neurological recovery (CPC score 1) occurred in 14/26 (54%) patients. CONCLUSIONS A protocol including E-CPR instituted by critical care physicians for refractory cardiac arrest which includes mechanical CPR, peri-arrest therapeutic hypothermia and ECMO is feasible and associated with a relatively high survival rate.

Air Versus Oxygen in ST-Segment Elevation Myocardial Infarction

Background— Oxygen is commonly administered to patients with ST-elevation–myocardial infarction despite previous studies suggesting a possible increase in myocardial injury as a result of coronary vasoconstriction and heightened oxidative stress. Methods and Results— We conducted a multicenter, prospective, randomized, controlled trial comparing oxygen (8 L/min) with no supplemental oxygen in patients with ST-elevation–myocardial infarction diagnosed on paramedic 12-lead ECG. Of 638 patients randomized, 441 patients had confirmed ST-elevation–myocardial infarction and underwent primary end-point analysis. The primary end point was myocardial infarct size as assessed by cardiac enzymes, troponin I, and creatine kinase. Secondary end points included recurrent myocardial infarction, cardiac arrhythmia, and myocardial infarct size assessed by cardiac magnetic resonance imaging at 6 months. Mean peak troponin was similar in the oxygen and no oxygen groups (57.4 versus 48.0 &mgr;g/L; ratio, 1.20; 95% confidence interval, 0.92–1.56; P=0.18). There was a significant increase in mean peak creatine kinase in the oxygen group compared with the no oxygen group (1948 versus 1543 U/L; means ratio, 1.27; 95% confidence interval, 1.04–1.52; P=0.01). There was an increase in the rate of recurrent myocardial infarction in the oxygen group compared with the no oxygen group (5.5% versus 0.9%; P=0.006) and an increase in frequency of cardiac arrhythmia (40.4% versus 31.4%; P=0.05). At 6 months, the oxygen group had an increase in myocardial infarct size on cardiac magnetic resonance (n=139; 20.3 versus 13.1 g; P=0.04). Conclusion— Supplemental oxygen therapy in patients with ST-elevation–myocardial infarction but without hypoxia may increase early myocardial injury and was associated with larger myocardial infarct size assessed at 6 months. Clinical Trial Registration— URL: http://www.clinicaltrials.gov. Unique identifier: NCT01272713.

Post Cardiac Arrest Syndrome A Review of Therapeutic Strategies

Out-of-hospital cardiac arrest (OHCA) is a common initial presentation of cardiovascular disease, affecting up to 325 000 people in the United States each year.1 In a recent meta-analysis of >140 000 patients with OHCA, survival to hospital admission was 23.8%, and survival to hospital discharge was only 7.6%.2 In patients who initially achieve return of spontaneous circulation (ROSC) after OHCA, the significant subsequent morbidity and mortality are due largely to the cerebral and cardiac dysfunction that accompanies prolonged whole-body ischemia. This syndrome, called the post cardiac arrest syndrome, comprises anoxic brain injury, post cardiac arrest myocardial dysfunction, systemic ischemia/reperfusion response, and persistent precipitating pathology3,4 (Table 1). The contribution of each of these components in an individual patient depends on various factors, including prearrest comorbidities, duration of the ischemic insult, and cause of the cardiac arrest. This review focuses on therapeutic strategies and recent developments in managing patients who are initially resuscitated from cardiac arrest. View this table: Table 1. Post Cardiac Arrest Syndrome: Pathophysiology and Potential Treatment Strategies There are 3 major aspects that require consideration in the management of the post cardiac arrest patient. After resuscitation, a decision must be made in relation to the appropriate triage of the OHCA patient. The next phase of management concerns the in-hospital treatment, which must address each component of the postarrest syndrome as appropriate for the individual patient. Finally, there are issues relating to prognostication and the deployment of various secondary prevention measures. Our recommended treatment algorithm is summarized in the Figure. This ideally follows from the implementation of basic and advanced life support measures, including effective cardiopulmonary resuscitation and defibrillation when appropriate, which are major determinants of outcome.2 Such an approach to care may be further modified according to the presence of other comorbidities and precipitating factors, which should be assessed …

Usefulness of Cooling and Coronary Catheterization to Improve Survival in Out-of-Hospital Cardiac Arrest

Survival rates after out-of-hospital cardiac arrest (OHCA) continue to be poor. Recent evidence suggests that a more aggressive approach to postresuscitation care, in particular combining therapeutic hypothermia with early coronary intervention, can improve prognosis. We performed a single-center review of 125 patients who were resuscitated from OHCA in 2 distinct treatment periods, from 2002 to 2003 (control group) and from 2007 to 2009 (contemporary group). Patients in the contemporary group had a higher prevalence of cardiovascular risk factors but similar cardiac arrest duration and prehospital treatment (adrenaline administration and direct cardioversion). Rates of cardiogenic shock (48% vs 41%, p = 0.2) and decreased conscious state on arrival (77% vs 86%, p = 0.2) were similar in the 2 cohorts, as was the incidence of ST-elevation myocardial infarction (33% vs 43%, p = 0.1). The contemporary cohort was more likely to receive therapeutic hypothermia (75% vs 0%, p <0.01), coronary angiography (77% vs 45%, p <0.01), and percutaneous coronary intervention (38% vs 23%, p = 0.03). This contemporary therapeutic strategy was associated with better survival to discharge (64% vs 39%, p <0.01) and improved neurologic recovery (57% vs 29%, p <0.01) and was the only independent predictor of survival (odds ratio 5.5, 95% confidence interval 1.2 to 26.2, p = 0.03). Longer resuscitation time, presence of cardiogenic shock, and decreased conscious state were independent predictors of poor outcomes. In conclusion, modern management of OHCA, including therapeutic hypothermia and early coronary angiography is associated with significant improvement in survival to hospital discharge and neurologic recovery.

Association of early withdrawal of life-sustaining therapy for perceived neurological prognosis with mortality after cardiac arrest

BACKGROUND Withdrawing life-sustaining therapy because of perceived poor neurological prognosis (WLST-N) is a common cause of hospital death after out-of-hospital cardiac arrest (OHCA). Although current guidelines recommend against WLST-N before 72h (WLST-N<72), this practice is common and may increase mortality. We sought to quantify these effects. METHODS In a secondary analysis of a multicenter OHCA trial, we evaluated survival to hospital discharge and survival with favorable functional status (modified Rankin Score ≤3) in adults alive >1h after hospital admission. Propensity score modeling the probability of exposure to WLST-N<72 based on pre-exposure covariates was used to match unexposed subjects with those exposed to WLST-N<72. We determined the probability of survival and functionally favorable survival in the unexposed matched cohort, fit adjusted logistic regression models to predict outcomes in this group, and then used these models to predict outcomes in the exposed cohort. Combining these findings with current epidemiologic statistics we estimated mortality nationally that is associated with WLST-N<72. RESULTS Of 16,875 OHCA subjects, 4265 (25%) met inclusion criteria. WLST-N<72 occurred in one-third of subjects who died in-hospital. Adjusted analyses predicted that exposed subjects would have 26% survival and 16% functionally favorable survival if WLST-N<72 did not occur. Extrapolated nationally, WLST-N<72 may be associated with mortality in approximately 2300 Americans each year of whom nearly 1500 (64%) might have had functional recovery. CONCLUSIONS After OHCA, death following WLST-N<72 may be common and is potentially avoidable. Reducing WLST-N<72 has national public health implications and may afford an opportunity to decrease mortality after OHCA.

Coronary Obstruction in Transcatheter Aortic Valve-in-Valve Implantation Preprocedural Evaluation, Device Selection, Protection, and Treatment

The majority of surgical heart valves being implanted during the past decade are bioprosthetic, tissue valves with limited durabiity.1–4 These tissue valves have limited durability.2–4 Recently, implantation of transcatheter valves inside failed surgically implanted aortic bioprostheses (valve-in-valve [VIV]) has been reported as a less-invasive alternative to repeat surgery.5 Although procedural success is achieved in the great majority of patients, this therapy is associated with several potential risks, including ostial coronary occlusion.6,7 Coronary obstruction is a serious procedural complication, associated with a high mortality rate.5–9 Importantly, during the recent years, several preprocedural and technical aspects have been described to identify those patients at increased risk. Therefore, in such high-risk patients, a modified VIV procedure, redo surgical valve replacement, or medical treatment only may be considered (Figure 1). We herein review the mechanisms of coronary obstruction, the optimal identification of patients at risk for coronary obstruction, and further describe technical considerations for preventing and treating this life-threatening complication. Figure 1. Flow chart of suggested evaluation and treatment of a candidate for aortic Valve-in-Valve implantation. (1) Details in Tables 1 to 3. (2) According to imaging and clinical characteristics. (3) Balloon valvuloplasty will optimally model the risk for coronary occlusion using a balloon size similar to the transcatheter heart valve (THV) device to be implanted. The risk for hemodynamic instability after valvuloplasty secondary to worsening regurgitation should be considered, and a THV device should be prepared for rapid implantation if needed. (4) If the patient is hemodynamically stable after valvuloplasty and the risk for left main occlusion seems high, considerations for redo surgery or medical treatment only could be made, otherwise coronary protection is advocated using a wire and a stent. (5) Consider using a retrievable THV device or a device with …

Usefulness of Transient and Persistent No Reflow to Predict Adverse Clinical Outcomes Following Percutaneous Coronary Intervention

The no reflow phenomenon is reported to occur in >2% of all percutaneous coronary interventions (PCIs) and portends a poor prognosis. We analyzed data from 5,286 consecutive patients who underwent PCI from the Melbourne Interventional Group (MIG) registry from April 2004 through January 2008 who had 30-day follow-up completed. Patients without no reflow (normal reflow, n = 5,031) were compared to 255 (4.8%) with no reflow (n = 217 for transient no reflow, n = 38 for persistent no reflow). Patients with transient or persistent no reflow were more likely to present with ST-elevation myocardial infarction (MI) or cardiogenic shock (p <0.0001 for the 2 comparisons). They were also more likely to have complex lesions (American College of Cardiology/American Heart Association type B2/C), have lesions within a bypass graft, require an intra-aortic balloon pump, receive glycoprotein IIb/IIIa inhibition, and have a longer mean stent length (p <0.0001 for all comparisons). In-hospital outcomes were significantly worse in those patients with transient or persistent no reflow, with increased death, periprocedural MI, renal impairment, and major adverse cardiac events (p <0.0001 for all comparisons). Similarly, transient and persistent no reflow portended worse 30-day clinical outcomes, with a progressive increase in mortality (normal reflow 1.7% vs transient no reflow 5.5% vs persistent no reflow 13.2%, p <0.0001), MI, target vessel revascularization, and major adverse cardiac events (p <0.0001 for all comparisons) compared to patients with normal flow. In conclusion, transient or persistent no reflow complicates approximately 1 in 20 PCIs and results in stepwise increases in in-hospital and 30-day adverse outcomes.

Vancouver Transcatheter Aortic Valve Replacement Clinical Pathway

We describe the development, implementation, and evaluation of a standardized clinical pathway to facilitate safe discharge home at the earliest time after transfemoral transcatheter aortic valve replacement. Between May 2012 and October 2014, the Heart Team developed a clinical pathway suited to the unique requirements of transfemoral transcatheter aortic valve replacement in contemporary practice. The components included risk-stratified minimalist periprocedure approach, standardized postprocedure care with early mobilization and reconditioning, and criteria-driven discharge home. Our aim was to reduce variation in care, identify a subgroup of patients suitable for early discharge (⩽48 hours), and decrease length of stay for all patients. We addressed barriers related to historical practices, complex multidisciplinary stakeholder engagement, and adoption of length of stay as a quality indicator. We retrospectively reviewed the experiences of 393 consecutive patients; 150 (38.2%) were discharged early. At baseline, early discharge patients had experienced less previous balloon aortic valvuloplasty, had higher left ventricular ejection fraction, better cognitive function, and were less frail than the standard discharge group (>48 hours). Early discharge was associated with the use of local anesthesia, implantation of balloon expandable device, avoidance of urinary catheter, and early removal of temporary pacemaker. Median length of stay was 1 day for early discharge and 3 days for other patients; 97.7% were discharged home. There were no differences in 30-day mortality (1.3%), disabling stroke (0.8%), or readmission (10.7%). The implementation of a transcatheter aortic valve replacement clinical pathway shifted the program’s approach to combine standardized processes and individual risk stratification. The Vancouver transcatheter aortic valve replacement clinical pathway requires a rigorous assessment to determine its efficacy, safety, and reproducibility.

Transcatheter mitral valve implantation with Tiara bioprosthesis

Mitral valve surgery is the gold standard therapy for severe mitral regurgitation, but can be associated with significant morbidity and mortality. Percutaneous mitral leaflet repair has recently been established as a viable alternative to surgery, but many patients are ineligible and repair may not be optimal. Transcatheter mitral valve implantation may be an alternate therapeutic option, particularly for high-risk patients. We outline the initial preclinical and first-in-human experience with the Tiara transapical mitral valve implantation system, highlighting the ease of implantation, proven feasibility and excellent haemodynamic performance.

Association between hospital post-resuscitative performance and clinical outcomes after out-of-hospital cardiac arrest

BACKGROUND Survival varies among those resuscitated from out-of-hospital cardiac arrest (OHCA). Evidence-based performance measures have been used to describe hospital quality of care in conditions such as acute coronary syndrome and major trauma. It remains unclear if adherence to performance measures is associated with better outcome in patients hospitalized after OHCA. OBJECTIVES To assess whether a composite performance score based on evidence-based guidelines for care of patients resuscitated from OHCA was independently associated with clinical outcomes. METHODS Included were 3252 patients with OHCA who received care at 111 U.S. and Canadian hospitals participating in the Resuscitation Outcomes Consortium (ROC-PRIMED) study between June 2007 and October 2009. We calculated composite performance scores for all patients, aggregated these at the hospital level, then associated them with patient mortality and favorable neurological status at discharge. RESULTS Composite performance scores varied widely (median [IQR] scores from lowest to highest hospital quartiles, 21% [20%, 25%] vs. 59% [55%, 64%]. Adjusted survival to discharge increased with each quartile of performance score (from lowest to highest: 16.2%, 20.8%, 28.5%, 34.8%, P<0.01), with similar findings for adjusted rates of good neurologic status. Hospital score was significantly associated with outcome after risk adjustment for established baseline factors (highest vs. lowest adherence quartile: adjusted OR of survival 1.64; 95% CI 1.13, 2.38). CONCLUSIONS Greater survival and favorable neurologic status at discharge were associated with greater adherence to recommended hospital based post-resuscitative care guidelines. Consideration should be given to measuring, reporting and improving hospital adherence to guideline-based performance measures, which could improve outcomes following OHCA.