Ventricular Decompression Research Articles

Remote cerebellar hemorrhage due to ventriculoperitoneal shunt in an infant: a case report

IntroductionCerebellar hemorrhage remote from the operative site is an unpredictable and rare complication in neurosurgery, with reported rates of morbidity and mortality in the literature of 8.4% and 7.8%, respectively. The range of procedures associated with remote cerebellar hemorrhage is diverse and includes both supratentorial and spinal procedures that entail significant cerebral spinal fluid loss or resection of supratentorial content. We present here the first documented case of remote cerebellar hemorrhage after controlled supratentorial cerebral spinal fluid drainage by ventriculoperitoneal shunt, and discuss the proposed pathophysiology and treatment.Case presentationWe present the case of a four-month-old Saudi Arabian male baby who presented with progressive symptoms and signs of congenital hydrocephalus. An uneventful ventriculoperitoneal shunting was performed with our patient recovering smoothly in the immediate postoperative period. On the next day, he had frequent episodes of vomiting and became lethargic. An urgent computed tomography scan of his brain revealed mild ventricular decompression and unexpected cerebellar hemorrhage. The infant was put under close observation, with marked spontaneous improvement over 48 hours and complete resolution of the hemorrhage on a follow-up computed tomography brain scan two weeks later. On regular outpatient visits at one, three and twelve months, he had no neurological deficit.ConclusionRemote cerebellar hemorrhage is a complication that remains enigmatic in terms of both the underlying mechanism and clinical behavior. Our case revealed that the risk factors identified in the literature are not sufficient in predicting patients at risk of developing remote cerebellar hemorrhage. Our report also adds to the growing body of evidence challenging the currently accepted hypothesis explaining the pathomechanism of remote cerebellar hemorrhage. It thereby remains an unpredictable hazard that requires further study and increased awareness, as many cases in the literature are incidental findings.

Impella and Extracorporeal Membrane Oxygenation

We report the case of a 34-year-old woman admitted in our institution for cardiogenic shock related to acute myocarditis. Initial hemodynamic instability required mechanical ventilation and peripheral venoarterial extracorporeal membrane oxygenation (ECMO). Secondary acute pulmonary edema after ECMO implantation required emergency left ventricular decompression with a percutaneous Impella Recover LP 5.0. After a short period of improvement, an unexpected technical problem led to the Impella Recover LP 5.0 arrest. The clinical situation quickly worsened, and the patient finally died. This case highlights the usefulness of Impella pump to unload left cardiac chambers but also its technical challenge when used in a patient on ECMO.

Feasibility and efficacy of bypassing the right ventricle and pulmonary circulation to treat right ventricular failure: an experimental study

BackgroundRight ventricular failure (RVF) and -support is associated with poor results. We aimed for a new approach of right - sided assistance bypassing the right ventricle and pulmonary circulation in order to better decompress the right ventricle and optimize left ventricular filling.MethodsFrom a microaxial pump (Abiomed), a low resistance oxygenator (Maquet and Novalung) and two cannulas (28 and 27 Fr) a system was set up and evaluated in an ovine model (n = 7). Connection with the heart was the right and left atrium. One hour the system was operated without RVF and turned of again. Then a RVF was induced and the course with the system running was evaluated. Complete hemodynamic monitoring was performed as well as echocardiography, flow measurement and blood gas analysis.ResultsThe overall performance of the system was reliable. Without RVF no relevant changes of hemodynamics occurred; blood gases were supra normal. In RVF a cardiogenic shock developed (MAP 35 ± 13 mmHg, CO 1,1 ± 0,7 l/min). Immediately after starting the system the circulation normalized (significant increase of MAP to 85 ± 13 mmHg, of CO to 4,5 ± 1,9). Echocardiography also revealed right ventricular recovery. After stopping the system, RVF returned.ConclusionsBypassing the right ventricle and pulmonary circulation with an oxygenating assist device, which may offer the advantages of enhanced right ventricular decompression and augmented left atrial filling, is feasible and effective in the treatment of acute RVF. Long time experiments are needed.

Novel combination of impella and extra corporeal membrane oxygenation as a bridge to full recovery in fulminant myocarditis.

A 31-year-old male was transferred to our hospital with severe heart failure due to viral myocarditis. He progressed to multiorgan failure requiring intubation and maximal doses of multiple vasopressors. Circulatory support was provided with an Impella device as a bridge to an extracorporeal membrane oxygenation (ECMO) system. On full mechanical cardiovascular support, the patient's hemodynamic status improved and ECMO and Impella were explanted after 48 hours. Three days later, he was extubated and continued on to a full recovery. There are no specific therapies for fulminant myocarditis but first-line treatment is supportive care. ECMO is commonly used in patients with severe heart failure. In severe systolic dysfunction, left ventricular decompression is required to reduce myocardial wall stress, decrease myocardial oxygen requirements, and enhance the chances of recovery. The Impella, an active support system, is less invasive than classical decompressive techniques and is associated with lower requirements for blood products with fewer thromboembolic complications. This is the only case reported of the contemporary use of Impella and ECMO as a bridge to full recovery in an adult with myocarditis. It also presents a novel use of the Impella device in decompressing the left ventricle of an adult patient on ECMO.

Invited Commentary

Mechanical circulatory support is increasingly used both as a bridge to heart transplantation (BTT) in eligible patients, and as destination therapy (DT) in those that are not. However, many patients with advanced heart failure fall somewhere in between. Certain conditions which make transplantation less than ideal are perhaps reversible with medications, time, or chronic left ventricular decompression. Implantable ventricular assist devices (VADs) allow these opportunities and can improve transplant candidacy.

Effects of Continuous-Flow Versus Pulsatile-Flow Left Ventricular Assist Devices on Myocardial Unloading and Remodeling

Continuous-flow left ventricular assist devices (LVAD) are increasingly used for patients with end-stage heart failure (HF). We analyzed the effects of ventricular decompression by continuous-flow versus pulsatile-flow LVADs on myocardial structure and function in this population. Sixty-one patients who underwent LVAD implantation as bridge-to-transplant were analyzed (pulsatile-flow LVAD: group P, n=31; continuous-flow LVAD: group C, n=30). Serial echocardiograms, serum levels of brain natriuretic peptide (BNP), and extracellular matrix biomarkers (ECM) were compared between the groups. Myocardial BNP and ECM gene expression were evaluated in a subset of 18 patients. Postoperative LV ejection fraction was greater (33.2±12.6% versus 17.6±8.8%, P<0.0001) and the mitral E/E' was lower (9.9±2.6 versus 13.2±3.8, P=0.0002) in group P versus group C. Postoperative serum levels of BNP, metalloproteinases (MMP)-9, and tissue inhibitor of MMP (TIMP)-4 were significantly lower in group P compared with group C (BNP: 552.6±340.6 versus 965.4±805.7 pg/mL, P<0.01; MMP9: 309.0±220.2 versus 475.2±336.9 ng/dL, P<0.05; TIMP4: 1490.9±622.4 versus 2014.3±452.4 ng/dL, P<0.001). Myocardial gene expression of ECM markers and BNP decreased in both groups; however, expression of TIMP-4 decreased only in group P (P=0.024). Mechanical unloading of the failing myocardium using pulsatile devices is more effective as indicated by echocardiographic parameters of systolic and diastolic LV function as well as dynamics of BNP and ECM markers. Therefore, specific effects of pulsatile mechanical unloading on the failing myocardium may have important implications for device selection especially for the purpose of bridge-to-recovery in patients with advanced HF.

In Vitro Evaluation of Ventricular Cannulation for Rotodynamic Cardiac Assist Devices

The influence of positioning and geometry of ventricular cannulas for contemporary continuous flow Left Ventricular Assist Devices (LVADs) was evaluated in a non-beating isolated heart preparation with borescopic visualization. Preload and LVAD flow were varied to evaluate degrees of ventricular decompression up to the point of ventricular collapse. The performance of a flanged cannula was compared to a conventional bevel-tipped cannula: quantitatively by the maximal flow attainable, and qualitatively by visualization of fluid tracer particles within the ventricular chamber. Three forms of ventricular suck-down occurred: concentric collapse, gradual entrainment and instantaneous entrainment. In some circumstances, unstable oscillations of the ventricle were observed prior to complete collapse. Under conditions of low preload, the flanged cannula demonstrated less positional sensitivity, provided greater flow, and exhibited fewer areas of stagnation than the beveled cannula. These observations warrant further consideration of a flanged ventricular cannula to mitigate complications encountered with conventional cannulae.

Invited Commentary

Invited Commentary

Deep hypothermia and aortic regurgitation without left ventricular venting, an animal model

Objective. Omitting ventricular decompression in resternotomy during cardiopulmonary bypass with deep hypothermia and circulatory arrest in patients with aortic regurgitation (AR) has recently been reported. The consequences of the dilated and non-dilated heart in conjunction with rapid and profound cooling were further studied in this randomized animal model. Methods. In five pigs (group A) AR was induced before cooling to 15°C and circulatory arrest of 30 minutes without left ventricular decompression. The animals were rewarmed with a competent valve, and weaning off bypass was attempted. In another five pigs (group B) the protocol was repeated with left ventricular decompression. Hemodynamics and the extent of myocardial infarction were evaluated. Results. During cooling in group A mean arterial and left atrial pressures were equalized and all animals suffered massive pulmonary edema. Only one animal could be weaned off bypass. The remaining four suffered considerable biventricular failure and succumbed when weaned off bypass. The animals in group B were stable throughout the experiment and easily weaned off bypass. Myocardial infarction was significantly more extensive in group A, 22 (6–36)% of left ventricular area, compared to group B; 3 (3–11)%, p = 0.016. Conclusions. In our experimental model aortic regurgitation without left ventricular venting in deep hypothermia and circulatory arrest has damaging effects on the myocardium.

Case 6—2010 Noncardiac Surgery in Patients With a Left Ventricular Assist Device

ENTRICULAR ASSIST DEVICES (VADs) are being implanted with greater frequency in patients with circulatory failure. These devices can be used for short-term support in hopes that the patient’s myocardium will recover, longerterm as a “bridge” to heart transplantation, or even as permanent solutions to end-stage heart failure, so-called “destination therapy.” As a result of expanded usage, these patients increasingly are presenting for noncardiac surgery. 1 Two cases of patients with left ventricular assist devices (LVADs) undergoing noncardiac surgery are presented. The discussion reviews the different types of devices, their pathophysiology, and the unique perioperative considerations when dealing with these challenging cases. CASE PRESENTATIONS* Case 1: Thoracoscopy A 58-year-old woman with an LVAD for idiopathic dilated cardiomyopathy was scheduled for left thoracoscopy for persistent pleural effusion. Past medical history included New York Heart Association class IV congestive heart failure, which had been managed medically for 10 years, with several months of worsening symptoms. She also had a history of migraines, obesity, mild asthma, and insulin-dependent diabetes mellitus. Her past surgical history included automated implantable cardioverter-defibrillator (ICD) placement, total abdominal hysterectomy with bilateral salpingo-oophorectomy, 3 caesarean sections, and tonsillectomy, all without anesthetic complications. Nine days earlier, she had a Heartmate II LVAD (Thoratec Corporation, Pleasanton, CA) implanted as a bridge to transplant. The original surgery included LVAD insertion, patent foramen ovale closure, and a DeVega tricuspid valve annuloplasty, which proceeded without complications. Intraoperative transesophageal echocardiography (TEE) performed immediately after LVAD implantation showed adequate left ventricular (LV) decompression, no valvular abnormalities, and adequate right ventricular (RV) function. Initial pulmonary artery pressure before LVAD placement was 32/15 mmHg, with minimal change after LVAD insertion. Postoperatively, the patient had been doing well except for some difficulty optimizing her international normalized ratio (INR) with warfarin. A left-sided pleural effusion was noted that did not resolve despite chest tube drainage, and the decision was made to perform a thoracoscopy and pleurodesis. Medications at the time of thoracoscopy included metoprolol, insulin glargine, furosemide, esomeprazole, docusate, and nebulized albuterol/ipratropium. Heparin infusion was stopped the morning of the scheduled thoracoscopy. The patient was allergic to amoxicillin/clavulanate, torsemide, and cefdinir. Vital signs immediately before the induction of anesthesia in

Mechanical Support and Medical Therapy Reverse Heart Failure in Infants and Children

Most infants and children implanted with ventricular assist devices (VADs) go on to cardiac transplantation. Recovery of dilated cardiomyopathies with the combination left ventricular decompression with a VAD and treatment with maximal medical therapy has been possible in some adults, and may be more feasible in infants and children. We used pulsatile and continuous flow VADs and the total artificial heart (TAH) as bridges to transplantation or to recovery. Candidates for native heart recovery were treated with maximal medical therapy for congestive heart failure and short-term dobutamine prior to weaning off device support. Since 1997, 28 infants and children, ages 1 month to 16 years, were implanted for durations of 3-107 days (mean 27). Eighteen received left VADs (LVAD), seven biventricular assist devices (BiVADs), and three TAHs. Device-related mortality was 7/28 (25%), leaving 21/28 (75%) surviving to transplantation or weaning from device support and 20/28 (71%) discharged from the hospital and currently surviving for 2 months to 9 years. Ten of 11 transplant recipients (90%) have survived 2 to 9 years. All 10 with recovered hearts are alive and well for 2 months to 5 years. Eight of 12 (67%) LVAD patients with dilated hearts recovered. None of the recovery patients were over 6 years old. Infants and children who have failed inotropic therapy may be treated with an LVAD and medical therapy for congestive heart failure anticipating native heart recovery. A variety of devices have been tried. All small LVADs yielded comparable results. Larger and older children also have a chance of recovery, but our experience with them is too small except to note that they do well with larger devices and transplantation.

Predictors for Biventricular Repair in Pulmonary Atresia with Intact Ventricular Septum

Pulmonary atresia with intact ventricular septum (PA-IVS) is a complex congenital heart defect with a large variety of right heart-sided morphologies. We undertook a retrospective review of 86 patients with PA-IVS with a special emphasis on the angiographic findings. The aim of the study was to determine predictors for biventricular repair. Initial surgical procedures depended on the right ventricular morphology, the tricuspid valve size and coronary anomalies. Fifty-five patients (64%) underwent decompression of the right ventricle (RV) as an initial procedure; 16 of them required an additional systemic-to-pulmonary artery shunt. Twenty-six patients (30%) had only a systemic-to-pulmonary artery shunt as their initial procedure. Five patients underwent interventional procedures performed by pediatric cardiologists. Biventricular repair was possible in 56 patients (65%). Univentricular palliation was achieved in 16 patients. Fourteen patients had only palliation with a systemic-to-pulmonary artery shunt. Mean tricuspid valve size was significantly bigger in patients with biventricular repair (z-score -3.6 +/- 2.6) than in patients who did not undergo biventricular repair (-5.2 +/- 1.7, P = 0.003). Predictors for biventricular repair were right ventricular decompression with or without systemic-to-pulmonary artery shunt ( P < 0.001), tripartite right ventricle ( P < 0.001) and the absence of coronary fistulae ( P < 0.001). Long-term survival was 80% +/- 13% at 25 years for patients undergoing biventricular repair. Decompression of the RV as an initial surgical procedure improves the possibility of achieving biventricular repair with good long-term results. However, morphological factors such as right ventricular size and the absence of coronary fistulae are significant predictors for biventricular repair.

Recovery of Dilated Cardiomyopathies in Infants and Children Using Left Ventricular Assist Devices

Most infants and children implanted with left ventricular assist devices (LVADs) are bridged to cardiac transplantation. Prioritizing recovery may decrease this trend. Patients were treated with LVAD ventricular decompression, medical heart failure therapy, and bolus therapy with a beta-agonist before weaning trials. Devices were removed if adequate function was observed. Eleven patients with a mean age of 1.7 years presented for LVAD implantation. The mean Z score for left ventricular end diastolic diameter (LVEDD) was +5.5 (+1.6 to +7.3), and the mean fractional shortening was 9% (5%-14%). They were on maximal medical therapy and inotropic support. Duration of device support ranged from 6 to 22 days (mean: 13 days). There were three deaths, one from preimplant anoxic brain damage and two from thromboembolism. Eight patients (73%) recovered, were explanted, and are alive 0.6-6 years with hearts that have a mean Z score for LVEDD of 1.0 (0.09-3.7) and fractional shortening of 23%-36%. Left ventricular assist device decompression of dilated left ventricles in infants and children led to long-term survival in 73%. Ventricular size was significantly reduced and contractility significantly increased. None of these patients required transplantation.

Effects on pre- and posttransplant pulmonary hemodynamics in patients with continuous-flow left ventricular assist devices

Pulsatile left ventricular assist devices have been shown to effectively reduce pulmonary hypertension in patients with end-stage heart failure. However, it remains to be seen whether newer continuous-flow left ventricular assist devices have a similar effect on pulmonary hypertension. The objective of this study was to determine whether the HeartMate II (Thoratec Corp, Pleasanton, Calif), a continuous-flow left ventricular assist device, is effective in improving pulmonary hemodynamics in the period after left ventricular assist device support and posttransplant. Fifty patients with end-stage heart failure underwent HeartMate II left ventricular assist device placement as a bridge to transplant. We evaluated their pulmonary hemodynamics with right-sided heart catheterization at baseline, after left ventricular assist device placement, and after heart transplant. The mean age of patients was 53.7 +/- 13.5 years. Ischemic etiology was present in 60% of the patients. After left ventricular assist device placement (mean duration, 135 +/- 60 days), mean systolic and diastolic pulmonary artery pressures decreased significantly from a baseline of 55.2 +/- 13.4 mm Hg and 27.3 +/- 6.8 mm Hg, respectively, to 35.9 +/- 10.8 mm Hg and 15.8 +/- 6.5 mm Hg, respectively (P < .001). Similarly, mean pulmonary vascular resistance decreased significantly from a baseline of 3.6 +/- 1.9 Woods units to 2.1 +/- 0.8 Woods units (P < .001). Posttransplant pulmonary hemodynamics also remained within normal limits, even in patients with previously severe pulmonary hypertension. Continuous-flow left ventricular assist devices effectively improve pulmonary hemodynamics associated with end-stage heart failure. Moreover, pulmonary hemodynamics remain within normal limits in the posttransplant period, even in patients with severe pulmonary hypertension. Therefore, adequate left ventricular decompression achieved with newer left ventricular assist devices can reverse significant pulmonary hypertension in patients with end-stage heart failure, making them eligible for cardiac transplantation.

Resternotomy Using Hypothermic Arrest

Resternotomy during closed chest cardiopulmonary bypass in hypothermia with or without circulatory arrest has been the preferred method for cardiac reoperations with adherent structures to the sternum. Here, we report our experience with this method and the effects of omitting ventricular decompression during the cooling procedure. Twenty reoperations were performed in 19 patients. In half (n = 10) of the procedures aortic regurgitation was present. Cardiopulmonary bypass was instituted in all patients before resternotomy, and the re-entry into the chest was performed either under hypothermic low-flow cardiopulmonary bypass or circulatory arrest. The reason for this choice of technique was adherent structures to the sternum posing a substantial risk for rupture during resternotomy in all patients. Rupture upon re-entry into the chest occurred in five operations. No patient died due to re-entry injury. The overall hospital mortality was 15%. No differences in postoperative outcomes including heart failure, biochemical markers indicating myocardial damage, and three-month follow-up assessment of cardiac function were found between patients with aortic regurgitation and patients without aortic regurgitation. Based on our experience, omitting ventricular decompression in resternotomy in hypothermia and arrested circulation or low-flow cardiopulmonary bypass can be safely used, and the presence of aortic regurgitation does not seem to influence the outcome.

Use of the Seldinger Type Movement Over a J-Shaped Stylet for Left Ventricular Vent Insertion

Access through the right superior pulmonary vein is a commonly used route for left ventricular vent insertion. Complex reshaping of the stylet and vent into a certain position or external guidance do not guarantee successful placement. In this article we describe a modified technique where the stylet sets up the position to allow consistent atraumatic advancement of the catheter across the mitral valve.

The potential of disproportionate growth of tricuspid valve after decompression of the right ventricle in patients with pulmonary atresia and intact ventricular septa

Tricuspid valve size is the major determinant of outcomes for patients with pulmonary atresia with intact ventricular septum. Lack of right ventricle-pulmonary artery continuity is associated with poor tricuspid valve growth (decrement in Z-value). However, most reports did not show evidence for disproportionate growth of the tricuspid valve after establishment of right ventricle-pulmonary artery continuity. We studied 40 patients with pulmonary atresia with intact ventricular septum who underwent initial right ventricular decompression for planned staged repair. The initial Z-value of the tricuspid valve diameter (Zt1) was obtained from the echocardiography-derived normal value. The late Z-value (Zt2) was measured before definitive repair or the last available Z-value, if definitive repair was not yet reached. The factors associated with the changes of Z-values (Zt2 - Zt1) were analyzed. The mean initial tricuspid Z-value (Zt1) was -6.2 +/- 3.5. After treatment (Zt2), the mean Z-value was -6.0 +/- 3.4 (n = 34). Overall, the tricuspid Z-values did not change. Individually, the change in Z-value (Zt2 - Zt1) was larger than +2 in 11 (32%) patients and smaller than -2 in 6 (18%) patients. Increases in Z-value (Zt2 - Zt1) were significantly associated with right ventricular pressure/left ventricular pressure ratio measured after initial palliation (r = -0.54; P = .001) and the initial tricuspid valve Z-value (Zt1) (r = -0.40; P = .02). Disproportional growth of the tricuspid valve can occur, especially in patients with small tricuspid valves and lower right ventricular pressures after decompression. The findings support the possibility of neonates with small tricuspid valves undergoing biventricular repair after right ventricular decompression surgery.

Hybrid Ventricular Decompression in Pulmonary Atresia With Intact Septum

Initial palliation for pulmonary atresia with intact ventricular septum continues to evolve in the face of significant early and late morbidity. In patients with suitable anatomy, decompression of the right ventricle may be the first step in treatment. A hybrid approach to right ventricular decompression, combining surgery and interventional catheterization techniques is described. Direct access to the right ventricle through a subxiphoid incision with transventricular sheath placement is used to provide optimum catheter position for radiofrequency perforation of membranous pulmonary atresia followed by balloon dilation. The technique may address key limitations of the traditional surgical and interventional approaches.

Severe, Transient Aortic Insufficiency After Bovine Pericardial Aortic Valve Replacement: A Cautionary Note

Three patients demonstrated severe, central aortic insufficiency noted immediately upon removal of the aortic cross clamp after aortic valve replacement with a bovine pericardial Edwards Magna valve. After maintaining left ventricular decompression, the aortic insufficiency resolved in less than 1 hour. Knowledge of this phenomenon will prevent unnecessary prosthetic valve explantation and re-replacement.

Surgical strategy for pulmonary atresia with intact ventricular septum: initial management and definitive surgery

Pulmonary atresia with intact ventricular septum is difficult to manage, and the surgical procedures are associated with high mortality and morbidity. The lesion is morphologically heterogeneous, with varying degrees of right ventricular and tricuspid valve hypoplasia. Aberrations of the coronary circulation are common. A single approach is impractical because the wide spectrum of right heart morphology makes a uniform surgical approach impossible. Anatomical criteria, such as the degree of tricuspid valve or right ventricular hypoplasia or whether a right ventricular infundibulum is present, have been used to assign the infants to single-ventricular or biventricular repair tracks. If the patient is considered a candidate for biventricular repair, right ventricular decompression, either alone or combined with a systemic-pulmonary artery shunt, is performed, whereas only a systemic-pulmonary artery shunt is performed in a candidate for single-ventricular repair. Several authors reported that the Z-value of the tricuspid valve diameter could be a guide to the initial procedure; however, poor interobserver reproducibility and wide normal ranges are serious limitations. Definitive operations, including biventricular repair, one-and-a-half ventricular repair, or Fontan-type operation, are performed to eliminate cyanosis. The most important problem when planning a strategy for a definitive repair is the fact that right ventricular growth and its contribution to pulmonary flow is difficult to predict before the operation. The management protocol should be determined by the precisely estimated morphology of the right ventricle and tricuspid valve, and the adequacy of the protocol should be analyzed based on surgical outcomes.