Emergency cardiopulmonary bypass support in patients with cardiac arrest in the catheterization laboratory

Joint British Societies' guideline on management of cardiac arrest in the cardiac catheter laboratory

More than 300 000 procedures are performed in cardiac catheter laboratories in the UK each year. The variety and complexity of percutaneous cardiovascular procedures have both increased substantially since the early days of invasive cardiology, when it was largely focused on elective coronary angiography and single chamber (right ventricular) permanent pacemaker implantation. Modern-day invasive cardiology encompasses primary percutaneous coronary intervention, cardiac resynchronisation therapy, complex arrhythmia ablation and structural heart interventions. These procedures all carry the risk of cardiac arrest.We have developed evidence-based guidelines for the management of cardiac arrest in adult patients in the catheter laboratory. The guidelines include recommendations which were developed by collaboration between nine professional and patient societies that are involved in promoting high-quality care for patients with cardiovascular conditions. We present a set of protocols which use the skills of the whole catheter laboratory team and which are aimed at achieving the best possible outcomes for patients who suffer a cardiac arrest in this setting. We identified six roles and developed a treatment algorithm which should be adopted during cardiac arrest in the catheter laboratory. We recommend that all catheter laboratory staff undergo regular training for these emergency situations which they will inevitably face.

ST-Elevation Myocardial Infarction Complicated by Out-of-Hospital Cardiac Arrest

5-10% of ST-elevated myocardial infarctions (STEMI) present with out-of-hospital cardiac arrest (OHCA). Although this subgroup of patients carries the highest in-hospital mortality among the STEMI population, it is the least likely to undergo coronary angiography and revascularization. Due to the concomitant neurologic injury, patients with OHCA STEMI require prolonged hospitalization and adjustments to standard MI management. This review systematically assesses the course of patients with OHCA STEMI from development of the arrest to hospital discharge, assesses the limiting factors for their treatment access, and presents the evidence-based optimal intervention strategy for this high-risk MI population.

The Evolving Role of the Cardiac Catheterization Laboratory in the Management of Patients With Out-of-Hospital Cardiac Arrest: A Scientific Statement From the American Heart Association

Coronary artery disease is prevalent in different causes of out-of-hospital cardiac arrest (OHCA), especially in individuals presenting with shockable rhythms of ventricular fibrillation/pulseless ventricular tachycardia (VF/pVT). The purpose of this report is to review the known prevalence and potential importance of coronary artery disease in patients with OHCA and to describe the emerging paradigm of treatment with advanced perfusion/reperfusion techniques and their potential benefits on the basis of available evidence. Although randomized clinical trials are planned or ongoing, current scientific evidence rests principally on observational case series with their potential confounding selection bias. Among patients resuscitated from VF/pVT OHCA with ST-segment elevation on their postresuscitation ECG, the prevalence of coronary artery disease has been shown to be 70% to 85%. More than 90% of these patients have had successful percutaneous coronary intervention. Conversely, among patients resuscitated from VF/pVT OHCA without ST-segment elevation on their postresuscitation ECG, the prevalence of coronary artery disease has been shown to be 25% to 50%. For these patients, early access to the cardiac catheterization laboratory is associated with a 10% to 15% absolute higher functionally favorable survival rate compared with more conservative approaches of late or no access to the cardiac catheterization laboratory. In patients with VF/pVT OHCA refractory to standard treatment, a new treatment paradigm is also emerging that uses venoarterial extracorporeal membrane oxygenation to facilitate return of normal perfusion and to support further resuscitation efforts, including coronary angiography and percutaneous coronary intervention. The burden of coronary artery disease is high in this patient population, presumably causative in most patients. The strategy of venoarterial extracorporeal membrane oxygenation, coronary angiography, and percutaneous coronary intervention has resulted in functionally favorable survival rates ranging from 9% to 45% in observational studies in this patient population. Patients with VF/pVT should be considered at the highest severity in the continuum of acute coronary syndromes. These patients have a significant burden of coronary artery disease and acute coronary thrombotic events. Evidence from randomized trials will further define optimal clinical practice.

A review of the fundamental principles and evidence base in the use of extracorporeal membrane oxygenation (ECMO) in critically ill adult patients

Extracorporeal membrane oxygenation (ECMO) comprises a commonly used method of extracorporeal life support. It has proven efficacy and is an accepted modality of care for isolated respiratory or cardiopulmonary failure in neonatal and pediatric populations. In adults, there are conflicting studies regarding its benefit, but it is possible that ECMO may be beneficial in certain adult populations beyond postcardiotomy heart failure. As such, all intensivists should be familiar with the evidence-base and principles of ECMO in adult population. The purpose of this article is to review the evidence and to describe the fundamental steps in initiating, adjusting, troubleshooting, and terminating ECMO so as to familiarize the intensivist with this modality.

Cardiopulmonary bypass as an adjunct for the noncardiac surgeon

The use of cardiopulmonary bypass (CPB) in noncardiac surgical settings has been increasingly developed and has greatly benefited noncardiac surgeon. A few years after the advent of CPB as well as profound hypothermic circulatory arrest in the early years, it was employed by neurosurgeons in cerebrovascular surgery and by general thoracic surgeons in carinal tumor resection. Indications for CPB were extended and modified year after year. It has facilitated not only the surgical management by surgeons of lesions that cannot be managed safely and effectively by conventional techniques, or conventional techniques carry significant risks to the patient, but also the preservation of the viability of multiple organ procurement, the practice of isolated limb perfusion for the treatment of malignancies of the extremities, and emergent cardiopulmonary resuscitation. Owing to the complications arising from CPB and profound hypothermic circulatory arrest, such as postoperative bleeding, coagulopathy, and neurologic deficits, efforts have been made to avoid these common hazards. Thus, innovative techniques including extracorporeal membrane oxygenation, percutaneous cardiopulmonary support, venovenous bypass, normothermic CPB, and minimally invasive approaches have emerged and played an important role as alternatives of standard CPB in decreasing morbidity and mortality and improving survival.

Systematic review of percutaneous cardiopulmonary bypass for cardiac arrest or cardiogenic shock states

BACKGROUND

Cardiogenic shock and cardiac arrest are common, lethal, debilitating and costly. Percutaneous cardiopulmonary bypass is an innovative strategy for treating these disorders that consists of rapid initiation of cardiopulmonary bypass and extracorporeal maintenance of circulation until restoration of an effective cardiac output. Multiple case reports suggest that percutaneous bypass is efficacious in patients with these disorders but these experiences have not been collated. Therefore, we have reviewed systematically the published experience with percutaneous bypass in patients with cardiogenic shock or cardiac arrest.

OBJECTIVES

The objectives were to describe the proportion of patients with cardiogenic shock or cardiac arrest who achieved restoration of spontaneous circulation or survival to discharge with percutaneous bypass. A secondary objective was to describe adverse effects associated with percutaneous bypass, if feasible.

DESIGN

Articles were identified by using a comprehensive search of English-language MEDLINE from 1966 to September 2005.

PATIENTS

Individuals in cardiogenic shock or cardiac arrest.

INTERVENTIONS

Percutaneous cardiopulmonary bypass.

ANALYSIS

Effects were summarized as inverse-variance weighted means, standard errors, median and interquartile range.

RESULTS

Included were 85 studies of 1494 patients with cardiogenic shock, cardiac arrest or both. Studies were case reports, case-series or case-control studies of heterogeneous interventions in heterogeneous patients. The proportion of patients weaned was mean, 76.8+/-4.2%, and median, 66.0% (IQR 50%, 100%). The proportion of patients who survived to discharge was mean, 47.4+/-4.5%, and median 40.0% (IQR 20%, 75%). Fifty-two studies included 533 patients in cardiogenic shock. The proportion of patients who survived to discharge was mean, 51.6+/-6.5%, and median 38.5% (IQR 23.4%, 76.3%). Fifty-four studies included 675 patients in cardiac arrest. The proportion of patients who survived to discharge was mean, 44.9+/-6.7%, and median, 42.3% (IQR 15.4%, 75%). Five studies with 286 subjects had both patients with cardiogenic shock or cardiac arrest.

CONCLUSIONS

Percutaneous bypass is an efficacious intervention in patients with cardiac arrest or cardiogenic shock. Adequately-powered experimental studies of current percutaneous bypass technologies are required to demonstrate whether it is safe, effective and cost-effective.

Experience with percutaneous venoarterial cardiopulmonary bypass for emergency circulatory support

OBJECTIVE

Mechanical circulatory support can maintain vital organ perfusion in patients with cardiac failure unresponsive to standard pharmacologic treatment. The purpose of the current study was to report complication and survival rates in patients supported with emergency percutaneous venoarterial cardiopulmonary bypass because of prolonged cardiogenic shock or cardiopulmonary arrest.

DESIGN

Retrospective clinical study.

SUBJECTS

A total of 46 patients supported with venoarterial cardiopulmonary bypass, 25 because of cardiogenic shock unresponsive to pharmacologic therapy and 21 because of cardiopulmonary arrest unresponsive to standard advanced cardiac life support.

RESULTS

In 41 of the 46 patients (89%), stable extracorporeal circulation was established; in five patients (11%), femoral cannulation was accomplished only after a surgical cutdown. A total of 28 patients were weaned from cardiopulmonary bypass (19 of 25 patients with cardiogenic shock vs. 9 of 21 patients with cardiopulmonary arrest, p =.03), and 13 patients had long-term survival (10 of 25 patients with cardiogenic shock vs. 3 of 21 patients with cardiopulmonary arrest, p =.1). Complications directly related to the use of cardiopulmonary bypass were found in 18 patients (39%), major complications related to femoral cannulation being the most common single cause for bypass-associated morbidity (eight patients, 17%).

CONCLUSIONS

Long-term survival rates after emergency percutaneous cardiopulmonary bypass are encouraging in patients with an underlying cardiocirculatory disease amenable to immediate corrective intervention (angioplasty, surgery, transplantation).

Improvement of bypass circuit biocompatibility: comparison and combination of heparin-coated circuit and nitric oxide gas infusion

OBJECTIVES

Nitric oxide (NO) gas infusion to the oxygenator, as well as heparin-coated bypass circuits, have been reported to attenuate blood activation induced by the interaction with the artificial surfaces of an extracorporeal bypass circuit. Using a mock circulation model, we compared the effect of each and also evaluated the effect of their combination on attenuating bypass-induced blood activation.

METHODS

A miniature closed bypass circuit was primed with diluted fresh human blood and perfused for 180 minutes using a centrifugal pump. NO gas (0, 50, or 100 ppm) was infused to the oxygenator sweep gas of either a non-heparin-coated or a heparin-coated circuit. Platelet counts, beta-thromboglobulin, platelet factor 4, complement-3 activation products and granulocyte elastase were measured at 0, 30, 60, 120, and 180 minutes after starting the perfusion.

RESULTS

One hundred ppm of NO was statistically equivalent to the heparin-coated circuit for attenuating bypass-induced blood activation, and a combination of the two significantly surpassed the results of either modification alone. Fifty ppm of NO alone provided only a slight attenuation of blood activation as compared with the non-heparin-coated circuit, though the difference was not significant. A combination of 50 ppm NO and the heparin-coated circuit did not significantly enhance the effects of the heparin-coated circuit alone.

CONCLUSIONS

The combination of NO gas infusion and heparin-coated circuits appears to be a useful and promising modification for enhancing the attenuation of bypass-induced blood activation, though the optimal dose of NO infusion in terms of effectiveness and adverse effects to the whole body remains to be established.

Cardiopulmonary and cerebral resuscitation

The future of cardiopulmonary resuscitation lies in new technologies for monitoring and generating vital organ perfusion during cardiac arrest and the post-resuscitation phase and in pharmacologic agents that will enhance ROSC and reverse ischemia-reperfusion injury. ROSC is the first step toward survival, so interventions that improve ROSC deserve further investigation. Long-term survival with good neurologic recovery is the critical endpoint. Interventions recommended for clinical practice must therefore demonstrate improved long-term survival. The resources required to provide many of the interventions discussed in this article, principally invasive perfusion technologies, cannot be justified unless there is clear benefit. The allocation of such resources to provide intensive resuscitation and post-resuscitation support will need to be addressed from medical and societal viewpoints.

Percutaneous cardiopulmonary support with heparin-coated circuits in postcardiotomy cardiogenic shock. Efficacy and comparison with left heart bypass

OBJECTIVE

Percutaneous cardiopulmonary support, a simplified form of venoarterial bypass, using totally heparin-coated circuits, has recently come into clinical use. To clarify its efficacy in postcardiotomy cardiogenic shock to aid weaning from cardiopulmonary bypass, we compared results of percutaneous cardiopulmonary support with those of left heart bypass using a centrifugal pump.

METHODS

We reviewed 18 patients treated between 1991 and 1998 who could not be weaned from cardiopulmonary bypass. Nine were aided by totally heparin-coated percutaneous cardiopulmonary support (PCPS group), and 9 supported by left heart bypass using a centrifugal pump (LHB group). In both groups, activated clotting time was controlled at 150-200 seconds using minimal doses of heparin as needed.

RESULTS

Weaning and survival rates were higher in the PCPS group than in the LHB group (100% vs 55.6%, and 66.7% vs 22.2%). The PCPS group had a smaller amount of blood loss and needed a smaller amount of blood components in the immediate postoperative period. One percutaneous cardiopulmonary support patient required surgical re-exploration for postoperative bleeding (11.1%), but no clinical thromboembolic event occurred in the PCPS group. In the LHB group, 5 patients underwent surgical re-exploration for postoperative bleeding (55.6%), and 2 underwent thrombus extirpation in the left ventricle (22.2%).

CONCLUSIONS

Although this study was retrospective and historical backgrounds could have been involved, our data suggest that totally heparin-coated percutaneous cardiopulmonary support system appears more effective as an aid to weaning from cardiopulmonary bypass and in short-term circulatory support for patients in postcardiotomy cardiogenic shock.

Significance of percutaneous cardiopulmonary bypass support for volume reduction surgery with severe hypercapnia

In patients with reduced respiratory function, lung resection is associated with high risk because separate ventilation is generally needed for safe management. For patients with end-stage emphysema, intraoperative respiratory management is important and particularly difficult because neither incomplete oxygenation nor selective ventilation can be performed, so the operation may be interrupted. In this study, we assess the effectiveness of the percutaneous cardiopulmonary support (PCPS) system for lung volume reduction surgery in patients with severe hypercapnia (arterial carbon dioxide tension >50 mm Hg) and discuss the significance of PCPS for patients who are beyond the standard criteria for lung volume reduction surgery (LVRS). We studied 3 patients with severe hypercapnia due to emphysema who underwent volume reduction surgery. One patient was previously treated surgically for contralateral pneumothorax. All patients had a severe smoking history and were suspected to have fragile lungs. During the operation. PCPS provided sufficient support flow. Intraoperative management using PCPS was easy, and no severe complications were observed. One patient exhibited severe hemodynamic deterioration on postoperative Day 15. Other patients' PaCO2 improved postoperatively. One had a calcification of a femoral artery, but there was no trouble inserting a cannula. Bilateral or unilateral volume reduction surgery was performed under PCPS in patients with end-stage emphysema. We conclude that PCPS is an adjunct to LVRS, useful for intraoperative management of some patients with severe hypercapnea, and the LVRS indications can be extended.

Emergency extracorporeal membrane oxygenation (ECMO)-supported percutaneous coronary interventions in the fibrillating heart

We describe two cases of refractory ventricular fibrillation complicating transcatheter interventional procedures. Extracorporeal membrane oxygenation was used in each to support percutaneous coronary revascularization in the fibrillating heart as a means of facilitating successful restoration of sinus rhythm. Cathet. Cardiovasc. Intervent. 48:402-405, 1999.

[Reperfusion therapy and mechanical circulatory support in patients in cardiogenic shock]

Cardiogenic shock is a state of inadequate tissue perfusion due to cardiac dysfunction, which is most commonly caused by acute myocardial infarction. The pathophysiology of cardiogenic shock is characterized by a downward spiral: ischemia causes myocardial dysfunction, which, in turn, augments the ischemic damage and the energetical imbalance. With conservative therapy, mortality rates for patients with cardiogenic shock are frustratingly high reaching more than 80%. Additional thrombolytic therapy has not been shown to significantly improve survival in such patients. Emergency cardiac catheterization and coronary angioplasty, however, seem to improve the outcome in shock-patients, which most probably is due to rapid and complete revascularization generally reached by angioplasty. In addition to interventional therapy with rapid coronary revascularization, the use of mechanical circulatory support may interrupt the vicious cycle in cardiogenic shock by stabilizing hemodynamics and the metabolic situation. Different cardiac assist devices are available for cardiologists and cardiac surgeons: 1. intraaortic balloon counterpulsation (IABP), 2. implantable turbine-pump (Hemopump), 3. percutaneous cardiopulmonary bypass support (CPS), 4. right heart, left heart, or biventricular assist devices placed by thoracotomy, and 5. intra- and extrathoracic total artificial hearts. Since percutaneous application is possible with IABP, Hemopump and CPS, these devices are currently used in interventional cardiology. The basic goals of the less invasive intraaortic balloon counterpulsation (IABP; Figure 1) are to stabilize circulatory collapse, to increase coronary perfusion and myocardial oxygen supply, and to decrease left ventricular workload and myocardial oxygen demand (Figure 2). Since the advent of percutaneous placement, IABP has been used by an increasing number of institutions (Figure 3). In addition to cardiogenic shock, the system may be of use in a variety of other indications in the catheterization laboratory and intensive care unit, including weaning from percutaneous cardiopulmonary bypass, in ischaemic left ventricular failure, in unstable angina, in high risk PTCA, and in prophylactic support in patients with myocardial infarction and successful revascularization. Animal experimental data showed that IABP may improve success of thrombolysis and recent clinical data suggest that survival is enhanced and transfer for revascularization is facilitated when patients with myocardial infarction and cardiogenic shock undergo thrombolysis and IABP rather than thrombolysis alone. A lot of studies had demonstrated before, that combined use of counterpulsation and revascularization therapy (i.e. coronary bypass surgery or angioplasty) may improve prognosis in patients with myocardial infarction complicated by cardiogenic shock (Table 1). In such patients, early treatment with IABP is most important: Multivariate analysis identified early IABP-support with a duration of shock to IABP-treatment of > or = 4 hours as an independent predictor of a positive short-term outcome. In shock-patients with postinfarction ventricular septal defect, IABP provides a marked hemodynamic improvement, and a significant decrease in shunt-flow (Figure 5). However, despite initial stabilization with IABP, such patients need immediate surgical repair of the septal defect to avoid hemodynamic deterioration. The rate of complications related to percutaneous IABP was significantly attenuated by employing catheters of reduced size. Using 9.5-F catheters, a long duration of counterpulsation emerged as the most significant factor associated with complications. In our hospital, those patients with 9.5-F catheters in whom counterpulsation did not exceed 48 hours had a low complication rate of 3.9%. The Hemopump is a catheter-mounted transvalvular left ventricular assist device intended for surgical placement via the femoral artery (Figures 6 and 7). (ABSTRACT TRUNCATED)

Survival using percutaneous cardiopulmonary support after acute myocardial infarction due to occlusion of the left main coronary artery--a report of two cases

Two cases of acute myocardial infarction due to an occlusion of the left main coronary artery (LMCA) are presented. Their cardiogenic shock was successfully treated with percutaneous cardiopulmonary support (PCPS), in addition to reperfusion therapy and an intraaortic balloon pump. The 2 patients were able to be weaned from PCPS and discharged from hospital. It is suggested that the early use of PCPS may be life-saving in patients with myocardial infarction due to the occlusion of the LMCA who have progressed to cardiogenic shock.

Use of percutaneous cardiopulmonary support system with rotary blood pump in graft replacement of the descending thoracic and thoracoabdominal aorta

Graft replacement of the descending thoracic or thoracoabdominal aorta was successfully performed in 3 patients using percutaneous cardiopulmonary bypass. Femoral inflow and outflow cannulas were inserted percutaneously after induction of anesthesia with the patient in supine position, and low flow normothermic bypass was established before thoracotomy. Next the patient was placed in a right lateral position to create an operating field. With this body position and even an almost prone position, which was sometimes necessary for easy dissection of adhesion of lung to the aneurysmal wall, the bypass flow was easily maintained adequately. The bypass circuit was coated with heparin, and the activated clotting time (ACT) was controlled to be between 150 and 200 s during the entire operating period. Percutaneous insertion of the cannulas avoided local bleeding in the groin, and the low ACT made control of hemorrhage in the operating field easy. For descending aortic surgery, heparin-coated percutaneous cardiopulmonary bypass proved to be a useful adjunctive measure.

Various problems during long-term percutaneous cardiopulmonary support

A 54-year-old man with a left ventricular free wall rupture following acute anterior myocardial infarction underwent a repair surgery with percutaneous cardiopulmonary support (PCPS). During surgery and postoperatively, PCPS provided sufficient support flow. The patient was successfully weaned from PCPS on the 15th postoperative day and discharged subsequently. In the management of cardiac rupture patients, PCPS has the merit of preventing rupture progression and the advantage of recovery of pulmonary function. However, there are several problems to solve. The support effectiveness and recovery of the patient's heart should be carefully evaluated. Effective left heart decompression also needs to be established. Heparin-coated circuits still need proper anticoagulation treatment to prevent thrombus formation especially while support flow is low. A circuit construction that allows easier maintenance and safer exchange of oxygenators and pump heads is suggested. Ischemia of the cannulated leg should be prevented by femoral artery perfusion.

Emergency cardiopulmonary bypass support in patients with severe cardiogenic shock after acute myocardial infarction

A total of 16 patients who developed severe cardiogenic shock were resuscitated with a percutaneous cardiopulmonary support system (PCPS). The etiology of shock was acute myocardial infarction (n = 7), or post-infarction left-ventricular (LV) free wall rupture (n = 9). After successful resuscitation with the PCPS, 15 patients underwent therapeutic interventions: closure of an LV rupture (n = 9), coronary artery bypass grafting (n = 4), percutaneous transluminal angioplasty (n = 1), and percutaneous transluminal coronary recanalization (n = 1). Of the 16 patients, 14 were weaned from PCPS or standard cardiopulmonary bypass. Six patients survived longer than 30 days, 3 (19 percent) of whom were discharged from the hospital. The long-term survival rate in the 6 patients who underwent coronary revascularization was 33 percent (2/6). Of the 9 patients with LV free wall rupture, 1 was discharged from the hospital. Even though it cannot be concluded, from this small number of patients, that cardiopulmonary resuscitation using PCPS improves survival, it appears that PCPS is a powerful resuscitative modality for seriously ill patients with acute myocardial infarction or LV rupture.

Anterograde perfusion in acute limb ischemia secondary to vascular occlusive cardiopulmonary support

Cardiopulmonary support (CPS) can resuscitate a patient with circulatory collapse during high-risk interventional procedures, although vascular complications may accompany its use. We report a patient with cardiogenic shock secondary to myocardial infarction who required extended CPS support associated with acute infarct-related coronary artery angioplasty and stent placement. Leg ischemia due to an occlusive cannula was resolved using a percutaneous anterograde perfusion device. In general, such devices may have application in patients dependent on mechanical support associated with limb ischemia.

Emergency use of cardiopulmonary bypass

Emergency cardiopulmonary support has been used in the United States since 1986. Physicians at participating centers for the National Registry of Elective Supported Angioplasty have contributed data on emergent cardiopulmonary support from their institutions. Results were analyzed to assess the benefits of cardiopulmonary support in patients with hemodynamic collapse. Patients with either cardiac arrest or hemodynamic collapse with cardiogenic shock unresponsive to pressor agents were placed emergently on cardiopulmonary support. Subsequent treatment comprised either angioplasty or surgical revascularization. Patients placed on cardiopulmonary support in < 20 minutes experienced a 41% survival rate across the entire registry of the participating centers of the National Cardiopulmonary Bypass Registry. Two centers with considerable experience demonstrated a 69% survival rate. Patients treated with emergency cardiopulmonary support because of hemodynamic collapse showed improved survival over any other hemodynamic support system. Results have improved for survival with increased operator experience, particularly in the early application group.

Pulmonary and left ventricular decompression by artificial pulmonary valve incompetence during percutaneous cardiopulmonary bypass support in cardiac arrest

BACKGROUND

In cardiac arrest, use of percutaneous cardiopulmonary bypass support (PCPS) may lead to left ventricular loading, with deleterious effects on the myocardium, and is often accompanied by an increase in pulmonary artery pressure. The present study was designed to assess the potential of artificially induced pulmonary valve incompetency to retrogradely decompress the left ventricle during PCPS in ventricular fibrillation.

METHODS AND RESULTS

Studies were performed using a standardized experimental animal model in sheep (n = 12; body weight, 77 to 112 kg). When PCPS was used during fibrillation, an increase in left ventricular pressure (from 21.4 +/- 5.0 mm Hg after 1 minute to 28.4 +/- 9.5 mm Hg after 10 minutes of fibrillation) was observed in all animals, with a simultaneous increase in pulmonary artery pressure in 6 animals, from 15.5 +/- 3.8 to 24.3 +/- 5.4 mm Hg (group A). In these animals, artificial pulmonary valve incompetency, which was induced by a special "pulmonary valve spreading catheter," led to effective decompression of both the pulmonary circulation (decrease in pulmonary artery pressure from 24.3 to 11.3 mm Hg) and the left ventricle (decrease in left ventricular pressure from 30.5 to 17.7 mm Hg). We simultaneously measured a decrease in the myocardial release of lactate (increase in arterial coronaryvenous difference in lactate content from -0.01 to 0.14 mmol/L), demonstrating the myocardial protective effect of the procedure. In contrast, in 6 animals without an increase in pulmonary artery pressure during PCPS (group B), artificial pulmonary valve incompetency did not reduce left ventricular loading, which was probably because of competent mitral valves in these animals.

CONCLUSIONS

In case of increasing pulmonary artery pressure during PCPS in cardiac arrest, artificial pulmonary valve incompetency might be a useful tool for effective pulmonary and retrograde left ventricular decompression.

Emergent percutaneous cardiopulmonary bypass in patients having cardiovascular collapse in the cardiac catheterization laboratory

Percutaneous cardiopulmonary bypass (PCB) was instituted in 30 initially stable patients who developed either cardiac arrest refractory to resuscitation (n = 7) or cardiogenic shock (mean arterial blood pressure < 50 mm Hg unresponsive to fluid resuscitation or vasopressors) (n = 23) after a catheterization laboratory complication. Events leading to collapse included abrupt closure during percutaneous transluminal coronary angioplasty (PTCA) (n = 22), complications from diagnostic cardiac catheterization (n = 6), left ventricular perforation during mitral valvuloplasty (n = 1), and right ventricular perforation during pericardiocentesis (n = 1). PCB was initiated within 20 minutes of cardiovascular collapse in 83% of patients (arrest: 21 +/- 13 minutes [range 10 to 50]; and shock: 17 +/- 6 minutes [range 10 to 30]). Mean arterial blood pressure increased on PCB from 0 to 56 mm Hg in patients with cardiac arrest and from 37 to 63 mm Hg in those with cardiogenic shock at mean PCB flow rates of 2.5 to 5.0 liters/min. Subsequent therapy on PCB included emergent cardiac surgery (n = 14), PTCA (n = 13) and medical therapy (n = 3). Six patients (20%) survived to hospital discharge (3 with cardiac surgery, 2 with PTCA, and 1 with medical therapy). All 7 patients with refractory cardiac arrest died despite further interventions on PCB, whereas 6 of 23 (26%) with cardiogenic shock survived to hospital discharge. Thus, in response to cardiovascular collapse in the catheterization laboratory, PCB does not salvage patients who do not regain a stable cardiac rhythm. PCB can stabilize patients who develop cardiogenic shock for further interventions which are lifesaving in only a minority of patients.

Enhanced recovery of ischemic myocardium by combining percutaneous bypass with intraaortic balloon pump support

Although percutaneous bypass (PB) can support the failing myocardium, regional ischemic damage may still occur beyond a coronary occlusion. This study sought to determine whether the addition of intraaortic balloon pump (IABP) support to PB would result in more optimal salvage of ischemic myocardium. In 30 pigs, the second and third diagonal vessels were occluded with snares for 90 minutes followed by 30 minutes of cardioplegic arrest and 3 hours of reperfusion with the snares released. During the period of coronary artery occlusion, 10 pigs were placed on PB, 10 pigs received PB plus IABP support, and 10 pigs received no support (the unmodified group). The hearts treated with the combination of PB and IABP support exhibited the highest wall motion scores (3.3 +/- 0.20 for the PB plus IABP group [p < 0.05 from the unmodified group and from the PB group]; versus 1.40 +/- 0.30 for the PB group versus 1.37 +/- 0.33 for the unmodified group), the least tissue acidosis (change in pH, -0.30 +/- 0.2 for the PB plus IABP group [p < 0.05 from the PB group] versus -0.60 +/- 0.10 for the PB group versus -0.41 +/- 0.13 for the unmodified group), and the least area of necrosis (25% +/- 5% for the PB plus IABP group [p < 0.05 from the unmodified group and from the PB group]; versus 43% +/- 2% for the PB group [p < 0.05 from the unmodified group] versus 73% +/- 3% for the unmodified group).(ABSTRACT TRUNCATED AT 250 WORDS)

Percutaneous Cardiopulmonary Bypass for Cardiogenic Shock

Percutaneous cardiopulmonary bypass was performed in 9 patients who developed cardiogenic shock. Of these patients, 5 were postoperative patients who developed cardiogenic shock on the day of operation. In 3 of these patients, intraaortic balloon pump was used in addition to percutaneous cardiopulmonary bypass. Two patients required percutaneous cardiopulmonary bypass in the cardiac catheterization laboratory for cardiogenic shock during angioplasty, and 2 other patients developed cardiogenic shock secondary to acute anterior wall myocardial infarction. Cardiopulmonary bypass was initiated with 18F femoral arterial and venous cannulae. Flow rates between 2.5 and 4.5 l/min and a mean blood pressure equal to or greater than 60mmHg were achieved. Of 5 postoperative patients, 3 survived and 2 died. Two patients who crashed during angioplasty were managed with emergency coronary artery bypass grafting, and both survived. Of 2 patients who developed cardiogenic shock following acute anterior wall myocardial infarction, 1 survived and 1 died. The surviving 6 patients were followed up for a mean period of 8 months. Five patients were in New York Heart Association Functional Class I, and 1 patient was in Class II.

Cardiopulmonary-cerebral resuscitation by using cardiopulmonary bypass through the femoral vein and artery in dogs

Twenty-seven dogs, divided into three groups, were subjected to a normothermic ventricular fibrillation (VF) cardiac arrest of 15 min and resuscitated by using cardiopulmonary bypass through the femoral veins and artery (F-F bypass). Group I (n = 15): Cardiac beating did not return in any dogs during an initial 3-min conventional cardiopulmonary resuscitation, but it returned 5.2 +/- 3.8 min (mean +/- S.D.) after the successive initiation of the F-F bypass in all dogs, except in one with bypass trouble. Intermittent burst waves appeared on the electroencephalogram and continuous waves returned, 90.0 +/- 24.7 min and 130.7 +/- 28.1 min after the start of resuscitation, respectively. Values of blood glucose, lactate and potassium 5-15 min after the F-F bypass were significantly higher than those before induction of VF, while those of blood pH, base excess, hemoglobin, hematocrit, platelet and serum protein decreased significantly. Group II (n = 7): Both local cerebral (CBF) and myocardial blood flow (MCBF) returned to the pre-arrest level soon after the initiation of the F-F bypass, even though spontaneous cardiac beating was not yet restored. Closed or open chest cardiac massage could not produce as much blood flow as the F-F bypass did. In the early stage of restoration of spontaneous circulation, temporary interruption of the bypass led to a decrease in both local CBF and MCBF. Group III (n = 5): Spontaneous circulation was restored in all five dogs 5.2 +/- 1.1 min after the institution of the F-F bypass, which was continued for 164 +/- 30 min under mild hypothermia. After intensive care for a subsequent 6-36 h, the animals barked, moved their forelegs and could drink water. The mean neurological deficit score (normal: 0, brain death: 500) was 100.6. However, macroscopic examination of the brain in two dogs with prominent recovery revealed atrophy of the central gyrus and microscopic examination revealed injuries of the vulnerable neurons of the brain.

Extracorporeal circulation as an alternative to open-chest cardiac compression for cardiac resuscitation

Open-chest direct cardiac compression represents a more potent but highly invasive option for cardiac resuscitation when conventional techniques of closed-chest cardiac resuscitation fail after prolonged cardiac arrest. We postulated that venoarterial extracorporeal circulation might be a more effective intervention with less trauma. In the setting of human cardiac resuscitation, however, controlled studies would be limited by strategic constraints. Accordingly, the effectiveness of open-chest cardiac compression was compared with that of extracorporeal circulation after a 15-min interval of untreated ventricular fibrillation in a porcine model of cardiac arrest. Sixteen domestic pigs were randomized to resuscitation by either peripheral venoarterial extracorporeal circulation or open-chest direct cardiac compression. During resuscitation, epinephrine was continuously infused into the right atrium, and defibrillation was attempted by transthoracic countershock at 2-min intervals. Systemic blood flows averaged 198 ml.kg-1.min-1 with extracorporeal circulation. This contrasted with direct cardiac compression, in which flows averaged only 40 ml.kg-1.min-1. Coronary perfusion pressure, the major determinant of resuscitability on the basis of earlier studies, was correspondingly lower (94 vs 29 mm Hg). Extracorporeal circulation, in conjunction with transthoracic DC countershock and epinephrine, successfully reestablished spontaneous circulation in each of eight animals after 15 min of untreated ventricular fibrillation. This contrasted with the outcome after open-chest cardiac compression, in which spontaneous circulation was reestablished in only four of eight animals (p = .038). We conclude that extracorporeal circulation is a more effective alternative to direct cardiac compression for cardiac resuscitation after protracted cardiac arrest.

Changing incidence and management of abrupt closure following coronary intervention in the new device era

Abrupt closure of the dilated segment occurs in approximately 4 to 7% of cases following conventional percutaneous coronary angioplasty. Additional balloon angioplasty reverses roughly 40% of these closures, to yield an overall 1.6 to 3.4% rate of emergent surgery. The impact of new devices on the incidence and reversal rate of abrupt closure has not been examined. Abrupt closure occurred in 80 (4.2%) of 1,919 consecutive coronary angioplasties performed in our single center, 389 (20%) of which were performed using newer interventions (208 Palmaz-Schatz stents, 170 directional coronary atherectomies, and 11 elective laser balloon angioplasties). Abrupt closure was less frequent following newer coronary interventions (1.8%) compared to standard balloon angioplasty (4.9%, P < 0.01), possibly reflecting case selection. When abrupt closure did occur, percutaneous rescue was successful in 53 (66%) patients, including 42 (53%) who were rescued using standard or perfusion balloon angioplasty, and 11 (13%) who were rescued using laser balloon balloon angioplasty after failure of additional angioplasty attempts. Medical therapy alone was used in 8 (10%), while emergent coronary bypass surgery was performed in 18 (23%), yielding an overall emergent surgery rate of 0.9%. Q-wave myocardial infarction was significantly less frequent (0.2%) following percutaneous rescue, compared to either medical therapy (25%) or emergent surgery (33%, P < 0.001). In our catheterization laboratory, use of these 3 new coronary interventional devices coincides with a trend towards a lower incidence of abrupt closure, a higher percutaneous rescue rate with reduced incidence of myocardial infarction, and a lower emergent bypass surgery rate.

Gas-exchange function of a preprimed pediatric oxygenator stored for one year for emergency cardiopulmonary bypass

To save priming time and perform more rapid initiation of emergency cardiopulmonary bypass for acute cardiopulmonary failure, an extracorporeal circuit with a hollow-fiber oxygenator (EL-2000 for pediatric use; Kurary Co. Ltd., Osaka, Japan) was preprimed, and the gas-exchange function was evaluated after 1 year of storage. EL-2000 has a dense polyolefin membrane with a surface area of 0.3 m2. When the bypass flow rates were 250, 500, 1,000, and 1,500 ml/min with 100% oxygen at the same flow rate as the bypass blood flow (namely, V/Q = 1) to the oxygenator, oxygen transport rates of the stored oxygenator were 19.6 +/- 0.3, 38.3 +/- 0.41, 64.4 +/- 0.9, and 76.4 +/- 2.7 ml/min (n = 5, mean +/- SD), respectively. PCO2 differences between pre- and postoxygenator blood (delta PCO2) were 18.6 +/- 1.4, 12.0 +/- 1.6, and 4.4 +/- 1.2 mm Hg at V/Q = 1 and the same bypass blood flow rates, respectively, excluding 1,500 ml/min, the data for which were excluded because of preparatory failure. PCO2 removal indices (defined as the ratio of delta PCO2 to PCO2 in preoxygenator blood) were 0.45 +/- 0.03, 0.29 +/- 0.12, and 0.10 +/- 0.03, respectively. Though the evaluation was done using only a single oxygenator, we feel strongly that the gas-exchange function of the preprimed dense-membrane hollow fiber oxygenator will be preserved even after 1 year of storage.

Emergency portable cardiopulmonary bypass for abrupt left main occlusion during coronary angioplasty. Excellent long-term survival

A 53-year-old man had total occlusion of the left main coronary artery with subsequent cardiac arrest during attempted angioplasty of the circumflex coronary artery. Conventional resuscitation was unsuccessful. However, emergent portable cardiopulmonary bypass support in the catheterization laboratory contributed to excellent long-term survival. Portable cardiopulmonary bypass support is a valuable resuscitative tool readily available in the catheterization laboratory setting.

Left ventricular rupture complicating percutaneous mitral commissurotomy: salvage using percutaneous cardiopulmonary bypass support

Left ventricular rupture resulting in death has been reported to be a complication of percutaneous mitral commissurotomy. We report a 71-year-old man in whom a left ventricular rupture occurred during percutaneous mitral commissurotomy and resulted in hemodynamic collapse due to acute cardiac tamponade. The patient was stabilized using percutaneously instituted cardiopulmonary bypass support with subsequent repair of the left ventricle and successful mitral valve replacement. Three months later this patient remains in New York Heart Class I.

Percutaneous cardiopulmonary bypass support in the catheterization laboratory: technique and complications

A safe and easily applied technique of percutaneous cardiopulmonary bypass support has been developed for use in the cardiac catheterization laboratory. The importance of this technique lies in its ability to maintain hemodynamic stability during high risk interventional procedures regardless of intrinsic cardiac function. Venous and arterial cannulas (18F) are inserted percutaneously over a stiff guide wire after sequential dilatation with 12F and 14F dilators. Bypass flow rates of up to 5 L/min can be achieved. This technique can be applied to support patients with cardiac arrest, hemodynamic collapse after abrupt closure during coronary angioplasty, and cardiogenic shock, as well as those undergoing high-risk elective coronary angioplasty. This form of support also permits transport of the patient to the operating room in a stable condition after an unsuccessful angioplasty. The complications are mostly related to cannula removal and can be minimized by the use of a proper technique. Although the ultimate role of this new technique remains to be completely defined, it appears that it will expand the patient population for whom coronary interventions can be applied.